Scientists have discovered a ground-breaking way of levitating ultra small objects, which may revolutionise the design of micro-machines, a new report says.
Physicists said they can create "incredible levitation effects" by manipulating so-called Casimir force, which normally causes objects to stick together by quantum force.
The phenomenon could be used to improve the performances of everyday devices ranging from car airbags to computer chips, say Professor Ulf Leonhardt and Dr Thomas Philbin from Saint Andrews University.
Casimir force -- discovered in 1948 and first measured in 1997 -- can be seen in a gecko's ability to stick to a surface with just one toe.
Now the British scientists say they can reverse the Casimir force to cause an object to repel rather than attract another in a vacuum.
"The Casimir force is the ultimate cause of friction in the nano world, in particular in some micro-electromechanical systems," said Leonhardt, writing in the August issue of New Journal of Physics.
"Micro or nano machines could run smoother and with less or no friction at all if one can manipulate the force," he added.
And he added: "In order to reduce friction in the nanoworld, turning nature's stickiness into repulsion could be the ultimate remedy. Instead of sticking together, parts of micromachinery would levitate."
Leonhardt stressed that the practise is possible only for micro-objects.
But he underlined that, although in principle it may one day be possible to levitate humans, that day is a long way off.
"At the moment, in practice it is only going to be possible for micro-objects with the current technology, since this quantum force is small and acts only at short ranges," he said.
"For now, human levitation remains the subject of cartoons, fairytales and tales of the paranormal."
Their research was to be published in the New Journal of Physics.
Source
Tuesday, August 7, 2007
Monday, August 6, 2007
Blog History
The term "weblog" was coined by Jorn Barger on 17 December 1997. The short form, "blog," was coined by Peter Merholz, who jokingly broke the word weblog into the phrase we blog in the sidebar of his blog Peterme.com in April or May of 1999.[6][7][8] This was quickly adopted as both a noun and verb ("to blog," meaning "to edit one's weblog or to post to one's weblog").
After a slow start, blogging rapidly gained in popularity: the site Xanga, launched in 1996, had only 100 diaries by 1997, but over 20 million as of December 2005. Blog usage spread during 1999 and the years following, being further popularized by the near-simultaneous arrival of the first hosted blog tools: Open Diary l(aunched in October 1998), LiveJournal (in March 1999) and blogger.com (in August 1999).
After a slow start, blogging rapidly gained in popularity: the site Xanga, launched in 1996, had only 100 diaries by 1997, but over 20 million as of December 2005. Blog usage spread during 1999 and the years following, being further popularized by the near-simultaneous arrival of the first hosted blog tools: Open Diary l(aunched in October 1998), LiveJournal (in March 1999) and blogger.com (in August 1999).
Friday, August 3, 2007
The Cure for Insomnia
The Cure for Insomnia, is a movie directed by John Henry Timmis IV, is officially the world's longest movie, according to Guinness World Records, as of its release in 1987. Running 5220 minutes (87 hours) in length, the movie has no plot, instead consisting of artist L. D. Groban reading his lengthy poem "A Cure for Insomnia" over the course of three and a half days, spliced with occasional clips from heavy metal and pornographic videos.
The movie is shot entirely on video, and its intended purpose actually was to be so unbelievably boring that it would put people to sleep thus curing insomnia. It is therefore disputed as to whether or not The Cure for Insomnia should even be considered as a candidate for the world's longest film in the strictest sense.
It was first played in its entirety at The School of the Art Institute in Chicago, Illinois from January 31 to February 3, 1987 in one continuous showing. It is not clear whether or not the movie has been shown since then. Considering that a DVD can only hold up to five hours of video at poor quality, The Cure for Insomnia would fill around 18 discs.
The movie is shot entirely on video, and its intended purpose actually was to be so unbelievably boring that it would put people to sleep thus curing insomnia. It is therefore disputed as to whether or not The Cure for Insomnia should even be considered as a candidate for the world's longest film in the strictest sense.
It was first played in its entirety at The School of the Art Institute in Chicago, Illinois from January 31 to February 3, 1987 in one continuous showing. It is not clear whether or not the movie has been shown since then. Considering that a DVD can only hold up to five hours of video at poor quality, The Cure for Insomnia would fill around 18 discs.
Thursday, August 2, 2007
Rises of the machine
This man story began, six years ago. One night, in a robbery while walking home, He was beaten and left for dead. His skull was crushed and his brain severely damaged. The doctor said if he pulled through at all, he'd be a vegetable for the rest of his life. The man could not speak or eat.On occasion he showed signs of awareness, and he moved his eyes or a thumb to communicate. His arms were useless. He was fed through a tube.
But researchers chose him for an experimental attempt to rev up his brain by placing electrodes in it. And here's how his mother describes the change in her son, now 38:
"My son can now eat, speak, watch a movie without falling asleep," she said Wednesday while choking back tears during a telephone news conference. "He can drink from a cup. He can express pain. He can cry and he can laugh.
"The most important part is he can say, `Mommy' and `Pop.' He can say, `I love you, Mommy' ... I still cry every time I see my son, but it's tears of joy."
The progress of the patient, who remains unidentified at the family's request, is described more formally in a report in Thursday's issue of the journal Nature.
Experts called the results encouraging but cautioned that the experimental treatment must be tried in more patients before its value can be assessed. The researchers are already proceeding with a larger study.
Before the electrodes were implanted, the man was in what doctors call a "minimally conscious state." That means he showed only occasional awareness of himself and his environment. In a coma or vegetative state, by contrast, patients show no outward signs of awareness.
There are no reliable statistics on how many Americans are in a minimally conscious state, but one estimate suggests 112,000 to 280,000. Doctors may try medications to improve their condition but no drugs have been firmly established as helpful.
The experimental treatment is called deep brain stimulation. It has been used for years in treating Parkinson's disease, although in this case the electrodes were implanted in slightly different places. The goal of the stimulation was to provide "drive" to areas of the brain that are critical for specific skills like speaking.
Similar stories of partial recovery from brain damage occasionally grab headlines, whether the improvement came from treatment or just out of the blue.
Terry Wallis of Arkansas lingered in a minimally conscious state for almost 20 years before he suddenly regained some ability to speak and move in 2003. In 2005, a former firefighter in Buffalo, N.Y., turned from being barely aware and almost mute for nearly a decade into a virtual chatterbox for 14 hours. His doctor had been trying a cocktail of drugs.
The man described in the Nature paper, despite his improvements, remains severely disabled in a rehabilitation facility for brain injury on the East Coast. (To preserve the man's anonymity, the researchers would not identify the facility or even reveal which state it is in).
He can't walk. While he has regained the ability to chew and swallow, he must be spoon-fed. He can demonstrate the motion of brushing his teeth, for example, but he can't actually do it. That's because tendons in his arms contracted after years of immobility, said study lead author Dr. Nicholas Schiff of Weill Cornell Medical College in New York.
The man doesn't initiate conversation but can reply to others, generally with one to three words, said Dr. Joseph Giacino, a co-lead author of the Nature study.
Several weeks ago, he recited the first half of the Pledge of Allegiance without assistance, said Giacino, of the JFK Johnson Rehabilitation Institute in Edison, N.J.
The man's electrodes are left on for 12 hours a day. He has continued to improve since the experiment formally ended in February 2006, the doctors said.
After the research was over, doctors started giving him the drug amantadine, which has shown some potential for treating people in a minimally conscious state. It's not clear whether amantadine can boost the effects of deep brain stimulation or vice versa, Giacino said.
Dr. James Bernat, a professor of neurology at Dartmouth Medical School who didn't participate in the new research, called the Nature report exciting and important. Further study is needed to sort out how many patients would respond and how to identify the minimally conscious patients with the best chance of being helped, he said.
He noted that a similar treatment did not help Terri Schiavo, the Florida woman in a vegetative state whose care triggered national controversy before her death in 2005. That's the typical outcome for electrical brain stimulation in vegetative states, he said.
Dr. Ross Zafonte of the University of Pittsburgh, who also was familiar with the study results, agreed that "we need to know more." He said the approach is "very interesting and holds great promise."
Wednesday, August 1, 2007
Seeing like a fish
The ability of zebrafish to regenerate damaged retinas has given scientists a clue about restoring human vision and could lead to an experimental treatment for blindness within five years.
British researchers said on Wednesday they had successfully grown in the laboratory a type of adult stem cell found in the eyes of both fish and mammals that develops into neurons in the retina.
In future, these cells could be injected into the eye as a treatment for diseases such as macular degeneration, glaucoma and diabetes-related blindness, according to Astrid Limb of University College London's (UCL) Institute of Ophthalmology.
Damage to the retina -- the part of the eye that sends messages to the brain -- is responsible for most cases of sight loss.
"Our findings have enormous potential," Limb said. "It could help in all diseases where the neurons are damaged, which is basically nearly every disease of the eye."
Limb and her colleagues studied so-called Mueller glial cells in the eyes of people aged from 18 months to 91 years and found they were able to develop them into all types of neurons found in the retina.
They were also able to grow them easily in the lab, they reported in the journal Stem Cells.
The cells have already been tested in rats with diseased retinas, where they successfully migrated into the retina and took on the characteristics of the surrounding neurons. Now the team is working on the same approach in humans.
"We very much hope that we could do autologous transplants within five years," Limb told Reuters.
Autologous transplants, initially on a trial basis, will involve manipulating cells and injecting them back into an individual's own eye. Eventually, Limb hopes it will also be possible to transfer the cells between different people.
"Because they are so easy to grow, we could make stem cell banks and have cell lines available to the general population, subject to typing as with blood transfusions," she said.
Just why zebrafish have an abundant supply of adult stem cells to regenerate their retinas, while they are rare in mammals, remains a mystery but Limb suspects it is because mammals have a limiting system to stop proliferation.
The new work on Mueller glial cells is the latest example of researchers exploring the potential of different kinds of stem cells in treating eye disease. Another team from UCL and Moorfield's Eye Hospital said in June they aimed to repair damaged retinas with cells derived from embryonic stem cells.
Source
Tuesday, July 31, 2007
Coffee against UVB
A moderate cafeine consumption and physical exercise would prevent the carcinogenic effects of the exposure to the ultraviolet radiations B of sun (UVB). Tests carried out on mice by researchers of Rutgers University show that this combination destroyed the cells whose ADN had been damaged by the UVB.
The study was carried out on mice particularly vulnerable to the rays of the sun. Four groups of rodents were created. The first group drank water containing cafeine (the equivalent of one or two coffee cups for the human). Another group made exercise, and third one combined both. A fourth reference group did not introduce cafeine and did not make a exercise. All the groups were exposed to UVB rays . The results show that the group that did both exercise & cafeine had a definitely higher capacity of destroying damaged cells than the other groups. The complete results are published in the review Proceedings for the National Academy of Sciences (PNAS).
The study was carried out on mice particularly vulnerable to the rays of the sun. Four groups of rodents were created. The first group drank water containing cafeine (the equivalent of one or two coffee cups for the human). Another group made exercise, and third one combined both. A fourth reference group did not introduce cafeine and did not make a exercise. All the groups were exposed to UVB rays . The results show that the group that did both exercise & cafeine had a definitely higher capacity of destroying damaged cells than the other groups. The complete results are published in the review Proceedings for the National Academy of Sciences (PNAS).
Monday, July 30, 2007
Wind Chill & Heat Index
To understand wind chill, one must have some appreciation of the concept of a thermal boundary layer. If you dive into the ocean and come back out again, a thin layer of water will adhere to your skin. We live in an ocean of air, and air, like water, can be said to “wet” the skin or any other object that is immersed in it. Right at the surface of the skin, the adhering air is still. Because air has some internal stickiness (viscosity), there is drag between the adhering air and the air molecules farther away from the skin. As a result, near the skin or any surface there is a zone of relatively still air that may be several millimetres thick. This is the boundary layer.
The boundary layer insulates your skin from the environment. If you blow on your arm, it can feel cool even though your breath is relatively warm because you have blown away the warm boundary layer air that was insulating the skin. If you do the same experiment in a hot sauna, instead of feeling cool, the spot you blow on can feel painfully hot, because you have blown away the boundary layer of sauna air that had been cooled by the skin and allowed the heat of the sauna to reach the skin more easily.
The Heat index (or humidex) is an index that combines air temperature and relative humidity to determine an apparent temperature — how hot it actually feels. The human body normally cools itself by perspiration, or sweating, in which the water in the sweat evaporates and carries heat away from the body. However, when the relative humidity is high, the evaporation rate of water is reduced. This means heat is removed from the body at a lower rate, causing it to retain more heat than it would in dry air. Measurements have been taken based on subjective descriptions of how hot subjects feel for a given temperature and humidity, allowing an index to be made which corresponds a temperature and humidity combination to a higher temperature in dry air.
For example, at 80 °F (approximately 27 °C), the heat index will agree with the actual temperature if the relative humidity is 45%, but at 110 °F (roughly 43 °C), any relative-humidity reading above 17% will make the Heat Index higher than 110 °F. Humidity is deemed not to raise the apparent temperature at all if the actual temperature is below approximately 68 °F (20 °C)
The boundary layer insulates your skin from the environment. If you blow on your arm, it can feel cool even though your breath is relatively warm because you have blown away the warm boundary layer air that was insulating the skin. If you do the same experiment in a hot sauna, instead of feeling cool, the spot you blow on can feel painfully hot, because you have blown away the boundary layer of sauna air that had been cooled by the skin and allowed the heat of the sauna to reach the skin more easily.
The Heat index (or humidex) is an index that combines air temperature and relative humidity to determine an apparent temperature — how hot it actually feels. The human body normally cools itself by perspiration, or sweating, in which the water in the sweat evaporates and carries heat away from the body. However, when the relative humidity is high, the evaporation rate of water is reduced. This means heat is removed from the body at a lower rate, causing it to retain more heat than it would in dry air. Measurements have been taken based on subjective descriptions of how hot subjects feel for a given temperature and humidity, allowing an index to be made which corresponds a temperature and humidity combination to a higher temperature in dry air.
For example, at 80 °F (approximately 27 °C), the heat index will agree with the actual temperature if the relative humidity is 45%, but at 110 °F (roughly 43 °C), any relative-humidity reading above 17% will make the Heat Index higher than 110 °F. Humidity is deemed not to raise the apparent temperature at all if the actual temperature is below approximately 68 °F (20 °C)
Friday, July 27, 2007
Diary of a Killer Cat
Ok, I wasn’t going to talk about it, because this is not the kind of article I usually discuss in my blog, but since yesterday I saw this article at least half a dozen times and it even made the 6 o’clock news. And since it from the New England Journal of Medicine, I decided to talk about it, just to add my own explanation.From the article on Yahoo!
“Oscar the cat seems to have an uncanny knack for predicting when nursing home patients are going to die, by curling up next to them during their final hours. His accuracy, observed in 25 cases, has led the staff to call family members once he has chosen someone. It usually means they have less than four hours to live.”
You can read the full article here: http://news.yahoo.com/s/ap/20070726/ap_on_fe_st/death_cat;_ylt=AmR5dcvU_SgPvsrcjCBhdt3q188F
I got ton of explanation for that:
Maybe it’s a psychological effect. The first time it happen it was a lucky shot and the rumor start off that this cat can predict death. Then once the cat was in your room, you were so sure that you gonna die, that you let yourself go.
Or even worst, maybe all theses people where actually allergic to cats and the cat simply kill them by staying by their side.
Thursday, July 26, 2007
Déjà Vu
Ever wonder how the strange déjà vu feeling happen? It’s had nothing to do with someone changing something in the matrix.
The term "déjà vu" (French for "already seen", also called paramnesia from the Greek word para for parallel and mnēmē for memory) describes the experience of feeling that one has witnessed or experienced a new situation previously. The term was coined by a French psychic researcher, Émile Boirac (1851–1917) in his book L'Avenir des sciences psychiques (The Future of Psychic Sciences), which expanded upon an essay he wrote while an undergraduate French concentrator at the University of Chicago. The experience of déjà vu is usually accompanied by a compelling sense of familiarity, and also a sense of "eeriness", "strangeness", or "weirdness". The "previous" experience is most frequently attributed to a dream, although in some cases there is a firm sense that the experience "genuinely happened" in the past. Déjà vu has been described as "remembering the future."
Basically, the brains receive many inputs (vision, smell, taste, etc). Under the normal process, all theses inputs are send in the conscious part of the brain. Then they are compared to what it is stored into your memory. Then the events (the collection of all the inputs at this moment) are stored into memory. This whole process only take a few milliseconds. This is who you can recognize your house or your lover. A déjà vu happen when the events (the inputs) would be stored into memory before the conscious part of the brain even receives the information and process it. This trigger the strange feeling of déjà vu because when the conscious part of the brain interrogate your memory for similar information, your memory will told you that an exact copy of this information is already stored … leading you to believe that this particular event have somehow already happened in the past.
The term "déjà vu" (French for "already seen", also called paramnesia from the Greek word para for parallel and mnēmē for memory) describes the experience of feeling that one has witnessed or experienced a new situation previously. The term was coined by a French psychic researcher, Émile Boirac (1851–1917) in his book L'Avenir des sciences psychiques (The Future of Psychic Sciences), which expanded upon an essay he wrote while an undergraduate French concentrator at the University of Chicago. The experience of déjà vu is usually accompanied by a compelling sense of familiarity, and also a sense of "eeriness", "strangeness", or "weirdness". The "previous" experience is most frequently attributed to a dream, although in some cases there is a firm sense that the experience "genuinely happened" in the past. Déjà vu has been described as "remembering the future."
Basically, the brains receive many inputs (vision, smell, taste, etc). Under the normal process, all theses inputs are send in the conscious part of the brain. Then they are compared to what it is stored into your memory. Then the events (the collection of all the inputs at this moment) are stored into memory. This whole process only take a few milliseconds. This is who you can recognize your house or your lover. A déjà vu happen when the events (the inputs) would be stored into memory before the conscious part of the brain even receives the information and process it. This trigger the strange feeling of déjà vu because when the conscious part of the brain interrogate your memory for similar information, your memory will told you that an exact copy of this information is already stored … leading you to believe that this particular event have somehow already happened in the past.
Wednesday, July 25, 2007
Boom, Here comes the Boom.
Actually, there is not just a single boom; as long as an aircraft is moving faster than sound through the atmosphere, a sonic boom can be heard each time the surface of a cone-shaped shockwave intersects with a set of eardrums.
Many authorities suggest that what happens in three dimensions in the air can most easily be visualized by watching the waves produced in front of a boat in the water, with the boat moving through them. If the boat is traveling at a great speed, the water cannot get out of the way of the bow, and the compression of the waves in front of it increases, producing great turbulence that collects as a V-shaped wave spreading in the wake of the boat.
For an airplane, the waves are sound waves, alternating areas of compression and rarefaction of the air. The waves are pushed closer and closer together as the plane flies faster and faster, again creating great turbulence and buffeting.
If the plane reaches speeds faster than the speed of sound, the turbulent waves collect in a cone-shaped wake, with a boom audible along its surface. The sound owes its explosive quality to the sudden, rapid changes in air pressure along the surface of the cone.
Many authorities suggest that what happens in three dimensions in the air can most easily be visualized by watching the waves produced in front of a boat in the water, with the boat moving through them. If the boat is traveling at a great speed, the water cannot get out of the way of the bow, and the compression of the waves in front of it increases, producing great turbulence that collects as a V-shaped wave spreading in the wake of the boat.
For an airplane, the waves are sound waves, alternating areas of compression and rarefaction of the air. The waves are pushed closer and closer together as the plane flies faster and faster, again creating great turbulence and buffeting.
If the plane reaches speeds faster than the speed of sound, the turbulent waves collect in a cone-shaped wake, with a boom audible along its surface. The sound owes its explosive quality to the sudden, rapid changes in air pressure along the surface of the cone.
Tuesday, July 24, 2007
Bite Me
Today, I was browsing random article on wikipedia. I usually don’t find anything really interesting using this method (and today’s no exception), but I was struck by the complexity of the article title: Gnathodynamometer. God, who comes up with theses names ?
A gnathodynamometer is apparently an instrument for measuring the force exerted in closing the jaws. Better yet, there’s an adjustable version called a bimeter gnathodynamometer (with an adjustable central-bearing point).
As per the inventor's (JN Snodgrass) design study, the instrument works well "in measuring maximal bite force and masticatory efficiency of incisor and molar teeth, respectively."
Experiments carried out with a Snodgrass gnathodynamometer at the Lerner Marine Laboratory in Bimini, Bahamas revealed that a 2m 6ft 6 ¾ in long dusky shark (Carcharhinus obscurus) could exert a force of 60 kg/132 lb between its jaws. This is the Strongest Bite Guinness World Record.
Now, this is what I call a crappy job … I don’t known how much the guy that is installing the gnathodynamometer into the shark mouth is being paid, but I sure that it’s ain’t enough.
A gnathodynamometer is apparently an instrument for measuring the force exerted in closing the jaws. Better yet, there’s an adjustable version called a bimeter gnathodynamometer (with an adjustable central-bearing point).
As per the inventor's (JN Snodgrass) design study, the instrument works well "in measuring maximal bite force and masticatory efficiency of incisor and molar teeth, respectively."
Experiments carried out with a Snodgrass gnathodynamometer at the Lerner Marine Laboratory in Bimini, Bahamas revealed that a 2m 6ft 6 ¾ in long dusky shark (Carcharhinus obscurus) could exert a force of 60 kg/132 lb between its jaws. This is the Strongest Bite Guinness World Record.
Now, this is what I call a crappy job … I don’t known how much the guy that is installing the gnathodynamometer into the shark mouth is being paid, but I sure that it’s ain’t enough.
Monday, July 23, 2007
Driving Direction
Why does people drive on the left in England? First let's put some fact on the table. England is not the only places where people drive at left. In fact most countries that was part of the British Empire also drive left. This include part of Africa, Australia, etc. About 34% of the world by population drive on the left, and 66% on the right. But this doesn’t answer why !!!
The first legal reference in Britain to an order for traffic to remain on the left occurred in 1756 with regard to London Bridge. The Highway Act 1773 contained a recommendation that horse traffic should remain on the left and this is enshrined in section 78 of the Highway Act 1835.
In the late 1700s, a shift from left to right took place in countries such as the United States, when teamsters started using large freight wagons pulled by several pairs of horses. The wagons had no driver’s seat, so the driver sat on the left rear horse and held his whip in his right hand. Seated on the left, the driver naturally preferred that other wagons overtake him on the left so that he could be sure to keep clear of the wheels of oncoming wagons. He did that by driving on the right side of the road.
The British, however, kept to the left. They had smaller wagons, and the driver sat on the wagon, usually on the right side of the front seat. From there he could use his long whip in his right hand without entangling it in the cargo behind him. In that position, on the right side of the wagon, the driver could judge the safety margin of overtaking traffic by keeping to the left side of the road. Countries that became part of the British Empire adopted the keep-left rule too, although there were some exceptions. Canada, for example, where the maritime provinces and Vancouver (later to become British Columbia) drove on the left, eventually changed to the right in order to make border crossings to and from the United States easier. Nova Scotia switched to driving on the right on 15 April 1923.
On most early motor vehicles, the driving seat was positioned centrally. Some car manufacturers later chose to place it near the centre of the road to help drivers see oncoming traffic, while others chose to put the driver's seat on the kerb side so that the drivers could avoid damage from walls, hedges, gutters and other obstacles. Eventually the former idea prevailed.
The first legal reference in Britain to an order for traffic to remain on the left occurred in 1756 with regard to London Bridge. The Highway Act 1773 contained a recommendation that horse traffic should remain on the left and this is enshrined in section 78 of the Highway Act 1835.
In the late 1700s, a shift from left to right took place in countries such as the United States, when teamsters started using large freight wagons pulled by several pairs of horses. The wagons had no driver’s seat, so the driver sat on the left rear horse and held his whip in his right hand. Seated on the left, the driver naturally preferred that other wagons overtake him on the left so that he could be sure to keep clear of the wheels of oncoming wagons. He did that by driving on the right side of the road.
The British, however, kept to the left. They had smaller wagons, and the driver sat on the wagon, usually on the right side of the front seat. From there he could use his long whip in his right hand without entangling it in the cargo behind him. In that position, on the right side of the wagon, the driver could judge the safety margin of overtaking traffic by keeping to the left side of the road. Countries that became part of the British Empire adopted the keep-left rule too, although there were some exceptions. Canada, for example, where the maritime provinces and Vancouver (later to become British Columbia) drove on the left, eventually changed to the right in order to make border crossings to and from the United States easier. Nova Scotia switched to driving on the right on 15 April 1923.
On most early motor vehicles, the driving seat was positioned centrally. Some car manufacturers later chose to place it near the centre of the road to help drivers see oncoming traffic, while others chose to put the driver's seat on the kerb side so that the drivers could avoid damage from walls, hedges, gutters and other obstacles. Eventually the former idea prevailed.
Friday, July 20, 2007
Nothing but blue sky ... and chemical
Every year, China launches thousands of rockets and artillery shells into the sky. They're not part of a set of war games or preparation for a battle with Taiwan, but rather a battle with the weather. Through its Weather Modification Program, the Chinese government hopes to control the fickle forces behind rain. Run by the Weather Modification Department, a division of the Chinese Academy of Meteorological Science, the program employs and trains 32,000 to 35,000 people across China, some of them farmers, who are paid $100 a month to handle anti-aircraft guns and rocket launchers.
The heavy weapons are used to launch pellets containing silver iodide into clouds. Silver iodide is thought to concentrate moisture and cause rain. The process is known as cloud seeding and China has invested heavily in it, using more than 12,000 anti-aircraft guns and rocket launchers in addition to about 30 planes
Chinese research into weather control began in 1958, when the practice was still in its early stages. With a population of more than 1.3 billion, China requires vast amounts of water. Cities like Beijing suffer from terrible smog, and rain can help clear away air pollution. The government is using cloud seeding to try to produce rain for farmers, stave off drought and fill water basins.
So how does it work? Even in areas with very low humidity, water is present in the sky and in clouds. A rainstorm happens after moisture collects around particles in the air, causing it to reach a level of saturation at which point it can no longer hold in that moisture. Cloud seeding essentially helps that process along, providing "nuclei" around which water condenses. These nuclei can be salts, calcium chloride, dry ice or silver iodide, which the Chinese use. Silver iodide is used because its form is similar to ice crystals. Calcium chloride is often used in warm or tropical areas.
The Chinese are not the first to use this technique.Noted atmospheric scientist Bernard Vonnegut (brother of novelist Kurt Vonnegut) is credited with discovering the potential of silver iodide for use in cloud seeding during 1946 while working for the General Electric Corporation in the state of New York. This property is related to a good match in lattice constant between the two types of crystal (the crystallography of ice later played a role in Kurt Vonnegut's novel Cat's Cradle). The first attempt at cloud seeding was in upstate New York during 1946. Vincent Schaefer, a General Electric chemist, caused snow to fall near Schenectady, NY after he dumped six pounds of dry ice into a cloud from a plane.
Silver iodide is mostly used for winter snowfall augmentation over mountains and hail suppression. While not a new technique hygroscopic seeding for enhancement of rainfall in warm clouds is enjoying a revival, based on some positive indications from research in South Africa, Mexico, and elsewhere. The hygroscopic material most commonly used is salt. It is postulated that hygroscopic seeding causes the droplet size spectrum in clouds to become more maritime (bigger drops) and less continental, stimulating rainfall through coalescence.
From March 1967 until July 1972, the US military Operation Popeye cloud seeded silver iodide to extend the monsoon season over North Vietnam, specifically the Ho Chi Minh Trail. The operation resulted in the targeted areas seeing an extension of the monsoon period an average of 30 to 45 days. The 54th Weather Reconnaissance Squadron carried out the operation to "make mud, not war."
One private organization which offered, during the 1970s, to conduct weather modification (cloud seeding from the ground using silver iodide flares) was Irving P. Crick and Associates of Palm Springs, California. They were contracted by the Oklahoma State University in 1972 to conduct such a seeding project to increase warm cloud rainfall in the Lake Carl Blackwell watershed. That lake was, at that time (1972-73), the primary water supply for Stillwater, Oklahoma and was dangerously low. The project did not operate for a long enough time to show statistically any change from natural variations. However, at the same time, seeding operations have been ongoing in California since 1948.
An attempt by the United States military to modify hurricanes in the Atlantic basin using cloud seeding in the 1960s was called Project Stormfury. Only a few hurricanes were tested with cloud seeding because of the strict rules that were set by the scientists of the project. It was unclear whether the project was successful; hurricanes appeared to change in structure slightly, but only temporarily. The fear that cloud seeding could potentially change the course or power of hurricanes and negatively affect people in the storm's path stopped the project.
Two Federal agencies have supported various weather modification research projects, which began in the early 1960s: The United States Bureau of Reclamation (Reclamation; Department of the Interior) and the National Oceanic and Atmospheric Administration (NOAA; Department of Commerce). Reclamation sponsored several cloud seeding research projects under the umbrella of Project Skywater from 1964-1988, and NOAA conducted the Atmospheric Modification Program from 1979-1993. The sponsored projects were carried out in several states and two countries (Thailand and Morocco), studying both winter and summer cloud seeding. More recently, Reclamation sponsored a small cooperative research program with six Western states called the Weather Damage Modification Program, from 2002-2006.
Funding for research has declined in the last two decades. A 2003 study by the United States National Academy of Sciences urges a national research program to clear up remaining questions about weather modification's efficacy and practice.
In Australia, CSIRO conducted major trials between 1947 and the early 1960s:
1947 – 1952: CSIRO scientists dropped dry ice into the tops of cumulus clouds. The method worked reliably with clouds that were very cold, producing rain that would not have otherwise fallen.
1953 – 1956: CSIRO carried out similar trials South Australia, Queensland and other States. Experiments used both ground-based and airborne silver iodide generators.
Late 1950s and early 1960s: Cloud seeding in the Snowy Mountains, on the Cape York Peninsula in Queensland, in the New England district of New South Wales, and in the Warragamba catchment area west of Sydney.
Only the trial conducted in the Snowy Mountains produced statistically significant rainfall increases over the entire experiment.
The heavy weapons are used to launch pellets containing silver iodide into clouds. Silver iodide is thought to concentrate moisture and cause rain. The process is known as cloud seeding and China has invested heavily in it, using more than 12,000 anti-aircraft guns and rocket launchers in addition to about 30 planes
Chinese research into weather control began in 1958, when the practice was still in its early stages. With a population of more than 1.3 billion, China requires vast amounts of water. Cities like Beijing suffer from terrible smog, and rain can help clear away air pollution. The government is using cloud seeding to try to produce rain for farmers, stave off drought and fill water basins.
So how does it work? Even in areas with very low humidity, water is present in the sky and in clouds. A rainstorm happens after moisture collects around particles in the air, causing it to reach a level of saturation at which point it can no longer hold in that moisture. Cloud seeding essentially helps that process along, providing "nuclei" around which water condenses. These nuclei can be salts, calcium chloride, dry ice or silver iodide, which the Chinese use. Silver iodide is used because its form is similar to ice crystals. Calcium chloride is often used in warm or tropical areas.
The Chinese are not the first to use this technique.Noted atmospheric scientist Bernard Vonnegut (brother of novelist Kurt Vonnegut) is credited with discovering the potential of silver iodide for use in cloud seeding during 1946 while working for the General Electric Corporation in the state of New York. This property is related to a good match in lattice constant between the two types of crystal (the crystallography of ice later played a role in Kurt Vonnegut's novel Cat's Cradle). The first attempt at cloud seeding was in upstate New York during 1946. Vincent Schaefer, a General Electric chemist, caused snow to fall near Schenectady, NY after he dumped six pounds of dry ice into a cloud from a plane.
Silver iodide is mostly used for winter snowfall augmentation over mountains and hail suppression. While not a new technique hygroscopic seeding for enhancement of rainfall in warm clouds is enjoying a revival, based on some positive indications from research in South Africa, Mexico, and elsewhere. The hygroscopic material most commonly used is salt. It is postulated that hygroscopic seeding causes the droplet size spectrum in clouds to become more maritime (bigger drops) and less continental, stimulating rainfall through coalescence.
From March 1967 until July 1972, the US military Operation Popeye cloud seeded silver iodide to extend the monsoon season over North Vietnam, specifically the Ho Chi Minh Trail. The operation resulted in the targeted areas seeing an extension of the monsoon period an average of 30 to 45 days. The 54th Weather Reconnaissance Squadron carried out the operation to "make mud, not war."
One private organization which offered, during the 1970s, to conduct weather modification (cloud seeding from the ground using silver iodide flares) was Irving P. Crick and Associates of Palm Springs, California. They were contracted by the Oklahoma State University in 1972 to conduct such a seeding project to increase warm cloud rainfall in the Lake Carl Blackwell watershed. That lake was, at that time (1972-73), the primary water supply for Stillwater, Oklahoma and was dangerously low. The project did not operate for a long enough time to show statistically any change from natural variations. However, at the same time, seeding operations have been ongoing in California since 1948.
An attempt by the United States military to modify hurricanes in the Atlantic basin using cloud seeding in the 1960s was called Project Stormfury. Only a few hurricanes were tested with cloud seeding because of the strict rules that were set by the scientists of the project. It was unclear whether the project was successful; hurricanes appeared to change in structure slightly, but only temporarily. The fear that cloud seeding could potentially change the course or power of hurricanes and negatively affect people in the storm's path stopped the project.
Two Federal agencies have supported various weather modification research projects, which began in the early 1960s: The United States Bureau of Reclamation (Reclamation; Department of the Interior) and the National Oceanic and Atmospheric Administration (NOAA; Department of Commerce). Reclamation sponsored several cloud seeding research projects under the umbrella of Project Skywater from 1964-1988, and NOAA conducted the Atmospheric Modification Program from 1979-1993. The sponsored projects were carried out in several states and two countries (Thailand and Morocco), studying both winter and summer cloud seeding. More recently, Reclamation sponsored a small cooperative research program with six Western states called the Weather Damage Modification Program, from 2002-2006.
Funding for research has declined in the last two decades. A 2003 study by the United States National Academy of Sciences urges a national research program to clear up remaining questions about weather modification's efficacy and practice.
In Australia, CSIRO conducted major trials between 1947 and the early 1960s:
1947 – 1952: CSIRO scientists dropped dry ice into the tops of cumulus clouds. The method worked reliably with clouds that were very cold, producing rain that would not have otherwise fallen.
1953 – 1956: CSIRO carried out similar trials South Australia, Queensland and other States. Experiments used both ground-based and airborne silver iodide generators.
Late 1950s and early 1960s: Cloud seeding in the Snowy Mountains, on the Cape York Peninsula in Queensland, in the New England district of New South Wales, and in the Warragamba catchment area west of Sydney.
Only the trial conducted in the Snowy Mountains produced statistically significant rainfall increases over the entire experiment.
Thursday, July 19, 2007
The Secret Origin of Mr. Potato Head
Mr. Potato Head was the invention of George Lerner in the late 1940s. The idea was originally to have it be a prize in breakfast cereal so that the separate parts could be distributed as cereal package premiums. But later Lerner showed the idea to the textile manufacturers Henry and Merrill Hassenfeld, who did business as the Hassenfeld Brothers (later shortened to Hasbro). and they loved it,so they bought back the rights. When the toy was first manufactured, it came with 30 accessories.
When it was first sold to the public in 1952 it became the first toy to be sold through national television advertising and netted Hasbro over USD$4 million in Mr. Potato Head sales in its first year of production. In 1953, Mrs. Potato Head was added, and soon after Brother Spud and Sister Yam completed the Potato Head family. Although originally produced as separate plastic parts to be stuck into a real potato or other vegetable, a plastic body was added to the kit in the late 1950's.
In 1973 the main potato part of the toy doubled in size and the size of its accessories were similarly increased. This was done mainly due to new toy child safety regulations that were introduced by the U.S. government. Hasbro also replaced the holes with flat slats, which made it impossible for users to put the face pieces and other body parts the wrong way around. In the 1980s Hasbro reduced their range of accessories for Mr. Potato Head to one set of parts. They did however reintroduce round holes in the main potato body, and once again parts were able to go onto the toy the wrong way around
Wednesday, July 18, 2007
Fear of the Dark
The firefly use of bioluminescence to attract mates or prey. It's capable of producing a "cold light" containing no ultraviolet rays, with a wavelength from 510 to 670 nanometers, pale yellowish or reddish green in color, with a lighting efficiency of 96%.
Bioluminescence is a very efficient process. 90 per cent of the firefly's energy is converted into light. By comparison, an incandescent electric bulb can convert only 10 percent of total energy into light, and the remainder is emitted as heat.
Light production in fireflies is due to a chemical reaction that occurs in specialized light-emitting organs, usually on the lower abdomen. The enzyme luciferase acts on luciferin in this organ to stimulate light emission. This reaction is of scientific interest. Genes coding for these substances have been inserted into many different organisms (Mice, silkworms, and potatoes). Luciferase is also used in forensics, and the enzyme has medical uses.
Tropical fireflies, particularly in Southeast Asia (Thailand and Malaysia), routinely synchronize their flashes among large groups, a startling example of spontaneous biological order. This phenomenon occurs through the night along river banks in the Malaysian jungles every day of the year. Current hypotheses about the causes of this behavior involve diet, social interaction, and altitude. In the United States, one of the most famous sightings of fireflies blinking in unison occurs near Elkmont, Tennessee in the Great Smoky Mountains during the second week of June.
Bioluminescence is a very efficient process. 90 per cent of the firefly's energy is converted into light. By comparison, an incandescent electric bulb can convert only 10 percent of total energy into light, and the remainder is emitted as heat.
Light production in fireflies is due to a chemical reaction that occurs in specialized light-emitting organs, usually on the lower abdomen. The enzyme luciferase acts on luciferin in this organ to stimulate light emission. This reaction is of scientific interest. Genes coding for these substances have been inserted into many different organisms (Mice, silkworms, and potatoes). Luciferase is also used in forensics, and the enzyme has medical uses.
Tropical fireflies, particularly in Southeast Asia (Thailand and Malaysia), routinely synchronize their flashes among large groups, a startling example of spontaneous biological order. This phenomenon occurs through the night along river banks in the Malaysian jungles every day of the year. Current hypotheses about the causes of this behavior involve diet, social interaction, and altitude. In the United States, one of the most famous sightings of fireflies blinking in unison occurs near Elkmont, Tennessee in the Great Smoky Mountains during the second week of June.
Tuesday, July 17, 2007
Easy as a, b, c
Can your name really affect your life? As contrived - or cruel - as the names Brooklyn, Romeo and Cruz might be, the happiness of the Beckham boys could be salvaged by their surname. Not, as you might think, because it's a famous name; if their father had been called David Wickham things could have been quite different.
A study revealed that people whose surnames began with letters at the beginning of the alphabet did indeed rate themselves as significantly more successful overall than those with surnames starting with lowly, end-of-the-alphabet initials.
The surname effect was especially pronounced when it came to career, suggesting that alphabetical discrimination was alive and well in the workplace. Interestingly, the effect was also more visible in men than in women. This may, of course, reflect the fact that many women change their surname when they marry. Perhaps women who are considering whether to adopt their husband's surname should take into account the alphabetical implications - or choose a real Alpha-male in the first place.What might account for this seemingly strange effect? One pattern in the data provided an important clue.
The surname effect became more pronounced in older age groups, suggesting that it was not due to childhood experiences, but rather that it built up gradually during our lives. It seems that constant exposure to being at the top or bottom of the alphabet league - the A-list or the Z-list - slowly makes an impact on the way in which people see themselves.
Again, as I reported before my surname investigation, past studies suggest that this is a real possibility.
In 1999, Nicholas Christenfeld and his colleagues from the University of California, San Diego, uncovered evidence suggesting that a person's initials might affect perhaps the most important aspect of their life - the moment of their death. Using a large, computerised database of death certificates, they identified people whose initials formed a positive-sounding word (such as A.C.E., H.U.G. and J.O.Y.), and those that had very negative connotations, like P.I.G., B.U.M. and D.I.E. Using factors such as race, year of death and socio-economic status as controls, the researchers discovered that men with positive initials lived approximately four and a half years longer than average, whereas those with negative initials died about three years early.
Women with positive initials lived an extra three years, although there was no detrimental effect for those with negative initials. Further analysis suggested that those with negative initials were especially likely to die from psychological causes, such as suicides and self-inflicted accidents.So should these results give those whose surname initial falls towards the end of the alphabet cause for concern? Well, as a Wiseman, and therefore someone with a lifetime's experience of coming towards the bottom of alphabetical lists, I take some comfort from the fact that the effect is very small. Then again, when you look at some of the best-known people around today - Blair, Brown, Bush, Cameron, Branson - it does make me wonder.
A study revealed that people whose surnames began with letters at the beginning of the alphabet did indeed rate themselves as significantly more successful overall than those with surnames starting with lowly, end-of-the-alphabet initials.
The surname effect was especially pronounced when it came to career, suggesting that alphabetical discrimination was alive and well in the workplace. Interestingly, the effect was also more visible in men than in women. This may, of course, reflect the fact that many women change their surname when they marry. Perhaps women who are considering whether to adopt their husband's surname should take into account the alphabetical implications - or choose a real Alpha-male in the first place.What might account for this seemingly strange effect? One pattern in the data provided an important clue.
The surname effect became more pronounced in older age groups, suggesting that it was not due to childhood experiences, but rather that it built up gradually during our lives. It seems that constant exposure to being at the top or bottom of the alphabet league - the A-list or the Z-list - slowly makes an impact on the way in which people see themselves.
Again, as I reported before my surname investigation, past studies suggest that this is a real possibility.
In 1999, Nicholas Christenfeld and his colleagues from the University of California, San Diego, uncovered evidence suggesting that a person's initials might affect perhaps the most important aspect of their life - the moment of their death. Using a large, computerised database of death certificates, they identified people whose initials formed a positive-sounding word (such as A.C.E., H.U.G. and J.O.Y.), and those that had very negative connotations, like P.I.G., B.U.M. and D.I.E. Using factors such as race, year of death and socio-economic status as controls, the researchers discovered that men with positive initials lived approximately four and a half years longer than average, whereas those with negative initials died about three years early.
Women with positive initials lived an extra three years, although there was no detrimental effect for those with negative initials. Further analysis suggested that those with negative initials were especially likely to die from psychological causes, such as suicides and self-inflicted accidents.So should these results give those whose surname initial falls towards the end of the alphabet cause for concern? Well, as a Wiseman, and therefore someone with a lifetime's experience of coming towards the bottom of alphabetical lists, I take some comfort from the fact that the effect is very small. Then again, when you look at some of the best-known people around today - Blair, Brown, Bush, Cameron, Branson - it does make me wonder.
Monday, July 16, 2007
The Winepire Strike Back
A few days ago, we talked about how wine can be good for your teeth and breathe. I then wonder … is it the end of the Mouthwash or is it a sweet revenge of the wine industry?
You way wonder why I talk about “sweet revenge”. I’ll explain this in a bit, but let’s start with a bit of history. Anthony van Leeuwenhoek, the famous 17th century microscopist, discovered living organisms (living, because they were motile) in deposits on the teeth (what we now call dental plaque). He also found organisms in water from the canal next to his home in Delft. He experimented with samples by adding vinegar or brandy and found that this resulted in the immediate immobilization or killing of the organisms suspended in water. Next he tried rinsing the mouth of himself and somebody else with a rather foul mouth with vinegar or brandy and found that living organisms remained in the dental plaque. He concluded - correctly - that the mouthwash either did not reach, or was not present long enough, to kill the plaque organisms.
That remained the state of affairs until the late 1960s when Harald Loe (at the time a professor at the Royal Dental College in Aarhus, Denmark) demonstrated that a chlorhexidine compound could prevent the build-up of dental plaque. The reason for chlorhexidine effectiveness is that it strongly adheres to surfaces in the mouth and thus remains present in effective concentrations for many hours. Rinses in this category include Listerine and Scope.
Active ingredients in commercial brands of mouthwash can include thymol, eucalyptol, hexetidine, methyl salicylate, menthol, chlorhexidine gluconate, benzalkonium chloride, cetylpyridinium chloride, methylparaben, hydrogen peroxide, domiphen bromide and sometimes fluoride, enzymes and calcium. Ingredients also include water, sweeteners such as sorbitol and sodium saccharine, and a significant amount of alcohol (around 20%).
Now, I think that you can see where I’m going. Hobo’s have been known to drink mouthwash as a cheap alcohol replacement (I’m not sure that’s very healthy though). In a sense, mouthwash took away a part of the wine market. Now, it’s wine turn!!! In fact, because of the alcohol content, it is possible to fail a breathalyzer test after rinsing with mouthwash; in addition, alcohol is a drying agent and may worsen chronic bad breath.
Go Wine!!!!
You way wonder why I talk about “sweet revenge”. I’ll explain this in a bit, but let’s start with a bit of history. Anthony van Leeuwenhoek, the famous 17th century microscopist, discovered living organisms (living, because they were motile) in deposits on the teeth (what we now call dental plaque). He also found organisms in water from the canal next to his home in Delft. He experimented with samples by adding vinegar or brandy and found that this resulted in the immediate immobilization or killing of the organisms suspended in water. Next he tried rinsing the mouth of himself and somebody else with a rather foul mouth with vinegar or brandy and found that living organisms remained in the dental plaque. He concluded - correctly - that the mouthwash either did not reach, or was not present long enough, to kill the plaque organisms.
That remained the state of affairs until the late 1960s when Harald Loe (at the time a professor at the Royal Dental College in Aarhus, Denmark) demonstrated that a chlorhexidine compound could prevent the build-up of dental plaque. The reason for chlorhexidine effectiveness is that it strongly adheres to surfaces in the mouth and thus remains present in effective concentrations for many hours. Rinses in this category include Listerine and Scope.
Active ingredients in commercial brands of mouthwash can include thymol, eucalyptol, hexetidine, methyl salicylate, menthol, chlorhexidine gluconate, benzalkonium chloride, cetylpyridinium chloride, methylparaben, hydrogen peroxide, domiphen bromide and sometimes fluoride, enzymes and calcium. Ingredients also include water, sweeteners such as sorbitol and sodium saccharine, and a significant amount of alcohol (around 20%).
Now, I think that you can see where I’m going. Hobo’s have been known to drink mouthwash as a cheap alcohol replacement (I’m not sure that’s very healthy though). In a sense, mouthwash took away a part of the wine market. Now, it’s wine turn!!! In fact, because of the alcohol content, it is possible to fail a breathalyzer test after rinsing with mouthwash; in addition, alcohol is a drying agent and may worsen chronic bad breath.
Go Wine!!!!
Friday, July 13, 2007
Dancing in the Rain
Today's, I learned a new term: Rain Shadow. The principle is nothigh spectacular, but still, I learned something new.A rain shadow is a dry region on the surface of the Earth that is leeward or behind of a mountain with respect to the prevailing wind direction. A rain shadow area is dry because, as moist air masses rise to the top of a mountain range or large mountain, the air cools and the maximum moisture content decreases until it reaches the dew point, where the water vapor condenses as rain or snow and falls on the windward side or top of the mountain. This process is called orographic precipitation. The effect of the process is the creation, on the leeward side, of an area of descending dry and warming air (see Foehn wind), and a region that is quite arid.
Thursday, July 12, 2007
May the force be with you
A couple of days ago, I was watching a movie when I start wondering why is there opening credits? My friend argued that it was an obligation by the Directors Guild of America (for American film or course). I then said ... what about Star wars ... and then it the silence came.
So I felt compelled to find the answer. In recent years, many major American motion pictures have done away with opening credits, with many films, such as Van Helsing, Batman Begins, and The Mummy Returns not even displaying the film title until the closing credits begin. George Lucas is credited (or blamed) with popularizing this with his Star Wars films which display only the film's title at the start. His decision to omit opening credits in his films Star Wars Episode IV: A New Hope (1977) and Star Wars Episode V: The Empire Strikes Back led him to resign from the Directors Guild of America. However, Hollywood had been releasing films without opening credits for many years before Lucas came along, most notably Citizen Kane and The Godfather. However, it was with the release of Lethal Weapon 2 in 1989 that the "title only" opening became an established form for summer blockbusters. Clint Eastwood has done away with opening credits (except for the title) in every film that he has directed since approximately 1982.
So I felt compelled to find the answer. In recent years, many major American motion pictures have done away with opening credits, with many films, such as Van Helsing, Batman Begins, and The Mummy Returns not even displaying the film title until the closing credits begin. George Lucas is credited (or blamed) with popularizing this with his Star Wars films which display only the film's title at the start. His decision to omit opening credits in his films Star Wars Episode IV: A New Hope (1977) and Star Wars Episode V: The Empire Strikes Back led him to resign from the Directors Guild of America. However, Hollywood had been releasing films without opening credits for many years before Lucas came along, most notably Citizen Kane and The Godfather. However, it was with the release of Lethal Weapon 2 in 1989 that the "title only" opening became an established form for summer blockbusters. Clint Eastwood has done away with opening credits (except for the title) in every film that he has directed since approximately 1982.
Wednesday, July 11, 2007
Coffee Facts
A cup of drip brewed coffee has about 115 milligrams of caffeine, an espresso (and percolated coffee) about 80mg, while instant coffee has about 65mg of caffeine. Decaffeinated coffee is not totally caffeine free, containing about 3mg of caffeine. A can of Coca-Cola has about 23mg of caffeine, Pepsi Cola 25mg, Mountain Dew 37mg, and TAB 31mg. Tea has about 40mg of caffeine, while an ounce of chocolate contains about 20mg.
The first Espresso machine was introduced in 1822 by the French, but it was the Italians who later perfected and distributed it.
Coffee is the world's most popular stimulant: 4 out of 5 Americans drink it, consuming more than 400 million cups a day. Consumption in Scandinavian countries is more than 12kg (26lb) per capita. With more than 25 million people employed in the industry, coffee is second only to oil in world trade.
The word "tip" is also related to coffee. It comes from old London coffeehouses where the waiters' brass boxes were etched with the inscription, "To Insure Promptness." In fact, it was in one such coffeehouses which belonged to a Mr Lloyd that a few cargo insurers got together to start the Lloyd's insurance company.
The first Espresso machine was introduced in 1822 by the French, but it was the Italians who later perfected and distributed it.
Coffee is the world's most popular stimulant: 4 out of 5 Americans drink it, consuming more than 400 million cups a day. Consumption in Scandinavian countries is more than 12kg (26lb) per capita. With more than 25 million people employed in the industry, coffee is second only to oil in world trade.
The word "tip" is also related to coffee. It comes from old London coffeehouses where the waiters' brass boxes were etched with the inscription, "To Insure Promptness." In fact, it was in one such coffeehouses which belonged to a Mr Lloyd that a few cargo insurers got together to start the Lloyd's insurance company.
Tuesday, July 10, 2007
How to walk on water
Do you ever wonder why water drops have a spherical shape? Because a sphere has the smallest possible surface area to volume ratio. An which force required such ratio ? Surface Tension.
Surface tension is caused by the attraction between the molecules of the liquid by various intermolecular forces. In the bulk of the liquid each molecule is pulled equally in all directions by neighboring liquid molecules, resulting in a net force of zero. At the surface of the liquid, the molecules are pulled inwards by other molecules deeper inside the liquid but they are not attracted as intensely by the molecules in the neighbouring medium (be it vacuum, air or another liquid). Therefore all of the molecules at the surface are subject to an inward force of molecular attraction which can be balanced only by the resistance of the liquid to compression. Thus the liquid squeezes itself together until it has the locally lowest surface area possible.
Recall that what nature really tries to minimize is potential energy. By increasing the surface area of the water, the water striders have increased the potential energy of that surface. But note also that the water striders' center of mass is lower than it would be if they were standing on a flat surface. So their potential energy is decreased. Indeed when you combine the two effects, the net potential energy is minimized. If the water striders depressed the surface any more, the increased surface energy would more than cancel the decreased energy of lowering the insects' center of mass. If they depressed the surface any less, their higher center of mass would more than cancel the reduction in surface energy.
Surface tension is caused by the attraction between the molecules of the liquid by various intermolecular forces. In the bulk of the liquid each molecule is pulled equally in all directions by neighboring liquid molecules, resulting in a net force of zero. At the surface of the liquid, the molecules are pulled inwards by other molecules deeper inside the liquid but they are not attracted as intensely by the molecules in the neighbouring medium (be it vacuum, air or another liquid). Therefore all of the molecules at the surface are subject to an inward force of molecular attraction which can be balanced only by the resistance of the liquid to compression. Thus the liquid squeezes itself together until it has the locally lowest surface area possible.
Recall that what nature really tries to minimize is potential energy. By increasing the surface area of the water, the water striders have increased the potential energy of that surface. But note also that the water striders' center of mass is lower than it would be if they were standing on a flat surface. So their potential energy is decreased. Indeed when you combine the two effects, the net potential energy is minimized. If the water striders depressed the surface any more, the increased surface energy would more than cancel the decreased energy of lowering the insects' center of mass. If they depressed the surface any less, their higher center of mass would more than cancel the reduction in surface energy.
Monday, July 9, 2007
Water Slide
I was looking for an article on surface tension when I felt onto theses facts:
Water is a common chemical substance that is essential to all known forms of life. In typical usage water refers only to its liquid form or state, but the substance also has the solid state, ice, and gaseous state, water vapor. About 1,460 teratonnes (Tt) of water cover 71% of Earth's surface, with 1.6% of water below ground in aquifers and 0.001% in the air as vapor, clouds, and precipitation.[2] Saltwater oceans hold 97% of surface water, glaciers and polar ice caps 2.4%; and other land surface water such as rivers and lakes 0.025%. Now, you have to be impressed by theses numbers.
Tomorrow: Why can water stride walk on water?
Water is a common chemical substance that is essential to all known forms of life. In typical usage water refers only to its liquid form or state, but the substance also has the solid state, ice, and gaseous state, water vapor. About 1,460 teratonnes (Tt) of water cover 71% of Earth's surface, with 1.6% of water below ground in aquifers and 0.001% in the air as vapor, clouds, and precipitation.[2] Saltwater oceans hold 97% of surface water, glaciers and polar ice caps 2.4%; and other land surface water such as rivers and lakes 0.025%. Now, you have to be impressed by theses numbers.
Tomorrow: Why can water stride walk on water?
Friday, July 6, 2007
My Two Cents
I’m sorry for yesterday’s absence, but I’m in some kind of rush at work. So today’s gonna be a quick one: Can a penny dropped from the top of a tall building kill a pedestrian?
A penny isn't the most aerodynamic of weapons. A combination of its shape and wind friction means that, tossed even from the 1,250-foot Empire State Building, it would travel fast enough merely to sting an unlucky pedestrian.
A penny isn't the most aerodynamic of weapons. A combination of its shape and wind friction means that, tossed even from the 1,250-foot Empire State Building, it would travel fast enough merely to sting an unlucky pedestrian.
Wednesday, July 4, 2007
Brain Teasers
Today’s fact is about a popular misconception that human uses only 10% of our brain. This misconception arose from a misunderstanding of neurological research in the late 1800s or early 1900s when researchers either discovered that only about 10% of the neurons in the brain are firing at any given time. Another possible origin of the misconception is that only 10% of the cells in the brain are neurons; the rest are glial cells that, despite being involved in learning, do not function in the same way that neurons do. If all of a person's neurons began firing at once, that person would not become smarter, but would instead suffer a seizure. In fact, studies have shown that the brains of more intelligent people are less active than the brains of less intelligent people when working on the same problem (which does not in any way mean that epileptics are less intelligent).
Tuesday, July 3, 2007
Fly Me to the Moon
When low on the horizon, the Moon can appear to be larger than when it's higher in the sky. It's all an illusion, scientists say, and it does not involve any enlarging effects of the atmosphere. Rather, it's all in your mind.
Here's how it works: Our brains think things on the horizon are farther away than stuff overhead, because we're used to seeing overhead clouds that are close compared to those on the horizon. In the mind's eye, the sky is a flattened dome. With this dome as a reference, we expect something on the horizon (such as the moon) to be father, and because it is actually no farther than when overhead, our brains goof and imagine that it is larger.
Now, that what I call an all natural enlargement process ;)
Friday, June 29, 2007
Silence is golden
I'm sick today ... I did try to find a good fact, but i'm too tired to find the answer I'm looking for. Meanwhile I still have a cool fact, but it's kind of short. Do you ever wonder why we had silent film ? I'm mean in back in 1896 the microphone was already invented.
Up until around 1925, most silent films were shot at slower speeds (or "frame rates") than sound films, typically at 16 to 23 frames per second depending on the year and studio, rather than 24 frames per second. Unless carefully shown at their original speeds they can appear unnaturally fast and jerky, which reinforces their alien appearance to modern viewers. At the same time, some scenes were intentionally undercranked during shooting in order to accelerate the action, particularly in the case of slapstick comedies. The intended frame rate of a silent film can be ambiguous and since they were usually hand cranked there can even be variation within one film. This implie that we couldnt just play a disk while the film was playing, since the film speed wasnt constant.
Although attempts to create sync-sound motion pictures go back to the Edison lab in 1896, the technology became well-developed only in the early 1920's. Although The Jazz Singer's release in 1927 marked the first commercially successful sound film, silent films formed the majority of features produced in both 1927 and 1928. Thus the modern sound film era may be regarded as coming to dominance beginning in 1929.
Next monday is also an holiday, so no fact until tuesday !!!
Have a great weekend.
Up until around 1925, most silent films were shot at slower speeds (or "frame rates") than sound films, typically at 16 to 23 frames per second depending on the year and studio, rather than 24 frames per second. Unless carefully shown at their original speeds they can appear unnaturally fast and jerky, which reinforces their alien appearance to modern viewers. At the same time, some scenes were intentionally undercranked during shooting in order to accelerate the action, particularly in the case of slapstick comedies. The intended frame rate of a silent film can be ambiguous and since they were usually hand cranked there can even be variation within one film. This implie that we couldnt just play a disk while the film was playing, since the film speed wasnt constant.
Although attempts to create sync-sound motion pictures go back to the Edison lab in 1896, the technology became well-developed only in the early 1920's. Although The Jazz Singer's release in 1927 marked the first commercially successful sound film, silent films formed the majority of features produced in both 1927 and 1928. Thus the modern sound film era may be regarded as coming to dominance beginning in 1929.
Next monday is also an holiday, so no fact until tuesday !!!
Have a great weekend.
Thursday, June 28, 2007
Stay Tuned
As you probably know, theres two major way to transmit information through radio wave. Amplitude modulation (AM) and frequency modulation (FM). (Theres also Phase modulation PM, but i dont think its ever been used).
Amplitude modulation transmits sound waves by adjusting the amplitude of the radio wave, or carrier wave to match the changes in the sound. In AM transmissions, the frequency is kept constant and the amplitude is adjusted. If radio was broadcast using visible light, this would mean that each radio signal would have its own color, and the signal would be broadcast by brightening and dimming the light.
Commercial AM radio stations transmit at set frequencies between 535 kHz and 1,605 kHz. The good thing about transmitting at these frequencies is that they can be reflected and refracted by the layer of the atmosphere called the ionosphere. This means that AM radio can be heard very far away, even over mountains. The problem with AM radio, though, is that interference from things like lightning, machinery, and UFO?s affect the amplitude of the signal. This is why during thunderstorms and alien attacks, AM radio sucks even worse than it usually does.
Frequency modulation transmits sound by adjusting the frequency of the radio wave. The mechanics behind frequency modulation are more difficult, but the main point is that the amplitude of the radio wave stays constant, while the frequency fluctuates around a basic carrier wave. This is like keeping a light at a constant brightness, but changing the color to transmit information.
Commercial FM stations transmit between 88 MHz and 108 MHz, frequencies which aren?t reflected by the ionosphere. This means that FM stations need to be placed in high spots so that they can cover more area. However, FM isn?t affected by changes in amplitude, so the things that interfere with AM signals don?t affect FM signals. Unfortunately, controlling annoying passengers who fiddle with your car radio is still beyond the power of modern science.
Amplitude modulation transmits sound waves by adjusting the amplitude of the radio wave, or carrier wave to match the changes in the sound. In AM transmissions, the frequency is kept constant and the amplitude is adjusted. If radio was broadcast using visible light, this would mean that each radio signal would have its own color, and the signal would be broadcast by brightening and dimming the light.
Commercial AM radio stations transmit at set frequencies between 535 kHz and 1,605 kHz. The good thing about transmitting at these frequencies is that they can be reflected and refracted by the layer of the atmosphere called the ionosphere. This means that AM radio can be heard very far away, even over mountains. The problem with AM radio, though, is that interference from things like lightning, machinery, and UFO?s affect the amplitude of the signal. This is why during thunderstorms and alien attacks, AM radio sucks even worse than it usually does.
Frequency modulation transmits sound by adjusting the frequency of the radio wave. The mechanics behind frequency modulation are more difficult, but the main point is that the amplitude of the radio wave stays constant, while the frequency fluctuates around a basic carrier wave. This is like keeping a light at a constant brightness, but changing the color to transmit information.
Commercial FM stations transmit between 88 MHz and 108 MHz, frequencies which aren?t reflected by the ionosphere. This means that FM stations need to be placed in high spots so that they can cover more area. However, FM isn?t affected by changes in amplitude, so the things that interfere with AM signals don?t affect FM signals. Unfortunately, controlling annoying passengers who fiddle with your car radio is still beyond the power of modern science.
Wednesday, June 27, 2007
Faster than light
Today I answered a question that I asked myself a while ago. I was browsing though yahoo answer to find today’s subject when I stumble across this question:
Physics question?
When you're in a car and the driver brakes suddenly, why do you get flung forward?
The answer is obviously inertia. The car stop but your body continues to move forward due to inertia … and then I remembered a question that I asked a long time ago to one of my teacher. If your running a 5 km/h in a train going a 300 km/h from an outside perspective (someone watching you from outside the train) you will be running a 305 km/h. The question is, If I open a flash light in a train going a 300 km/h, will the light will goes a e+300km/h from an outside point of view ?
The answer to that, is probably that the light doesn’t have any inertia since its doesn’t have a mass. The speed will remain the same from the outside view, but should be a bit slower actually from the inside. Not noticeably of course, but if we take this to the extreme and we were in a train going at e (light speed) and we would light up a flash light, from the inside of the train, the light would appear to be still. Well if the light is still you wouldn’t see it because it wouldn’t reach your eye, but still … you get the point J
Physics question?
When you're in a car and the driver brakes suddenly, why do you get flung forward?
The answer is obviously inertia. The car stop but your body continues to move forward due to inertia … and then I remembered a question that I asked a long time ago to one of my teacher. If your running a 5 km/h in a train going a 300 km/h from an outside perspective (someone watching you from outside the train) you will be running a 305 km/h. The question is, If I open a flash light in a train going a 300 km/h, will the light will goes a e+300km/h from an outside point of view ?
The answer to that, is probably that the light doesn’t have any inertia since its doesn’t have a mass. The speed will remain the same from the outside view, but should be a bit slower actually from the inside. Not noticeably of course, but if we take this to the extreme and we were in a train going at e (light speed) and we would light up a flash light, from the inside of the train, the light would appear to be still. Well if the light is still you wouldn’t see it because it wouldn’t reach your eye, but still … you get the point J
Tuesday, June 26, 2007
Red red wine. Stay close to me.
Do you remember the time when you wake up in the morning with a serious hangover? The first think we usually do when this happen is to brush our teeth to remove the taste of alcohol of our mouth … and the chunk of pizza from between your teeth. This can be a thing of the past if from now on, you get drunk on wine!!
Italian researchers have found that wine can help fight cavities. The test was done using some valpolicella (an Italian red wine) and pinot nero (an Italian white wine). The researchers started by stripping the alcohol out of the wine. They did that to prevent ethanol from interfering with their lab tests. Next, they marinated cavity-causing streptococcal bacteria in the wines. Both types of wine countered those bacteria and other streptococcal bacteria that cause some cases of throat infection and morning bad breath.
The researchers also isolated acids found in red wine and white wine and tested those acids against the same bacteria, which are called S. mutans and S. pyogenes.
The isolated acids were more effective against the bacteria than the wines. So the researchers reason that while wine fights S.mutans and S. pyogenes, wine also contains compounds that dilute those benefits, to some extent.
I already know that wine was good for the heart, but now there’s no excuses why not to get drunk J
(Before you toast the findings, remember that the study was done in test tubes. So it's too soon to count on a glass of wine to chase your cavities away.)
Italian researchers have found that wine can help fight cavities. The test was done using some valpolicella (an Italian red wine) and pinot nero (an Italian white wine). The researchers started by stripping the alcohol out of the wine. They did that to prevent ethanol from interfering with their lab tests. Next, they marinated cavity-causing streptococcal bacteria in the wines. Both types of wine countered those bacteria and other streptococcal bacteria that cause some cases of throat infection and morning bad breath.
The researchers also isolated acids found in red wine and white wine and tested those acids against the same bacteria, which are called S. mutans and S. pyogenes.
The isolated acids were more effective against the bacteria than the wines. So the researchers reason that while wine fights S.mutans and S. pyogenes, wine also contains compounds that dilute those benefits, to some extent.
I already know that wine was good for the heart, but now there’s no excuses why not to get drunk J
(Before you toast the findings, remember that the study was done in test tubes. So it's too soon to count on a glass of wine to chase your cavities away.)
Thursday, June 21, 2007
Eye Candy
There are 3 true colors in the eyes that determine the outward appearance; brown, yellow, and gray. How much of each color you have determines the appearance of the eye color. The color your eyes turn depends on how much of these colors are present. For example, green eyes have a lot of yellow and some brown, making them appear green. Blue eyes have a little yellow and little to no brown, making them appear blue. Gray eyes appear gray because they have a little yellow and no brown in them. Brown eyes appear brown because most of the eye contains the brown color. Brown is the most common, blue is second, and green is rarest.
This is the begging of a loooooooooong weekend ... see you on tuesday.
This is the begging of a loooooooooong weekend ... see you on tuesday.
Wednesday, June 20, 2007
Sinking bubbles
A long time subject of bar conversations is the Guinness cascade, where the gas bubbles appear to travel downwards in a pint glass of Guinness.
The effect is attributed to drag; bubbles that touch the walls of a glass are slowed in their travel upwards. Bubbles in the centre of the glass are, however, free to rise to the surface, and thus form a rising column of bubbles. The rising bubbles create a current by the entrainment of the surrounding fluid. As beer rises in the center, the beer near the outside of the glass falls. This downward flow pushes the bubbles near the glass towards the bottom. Although the effect occurs in any liquid, it is particularly noticeable in any dark nitrogen stout, as the drink combines dark-coloured liquid and light-coloured bubbles
The effect is attributed to drag; bubbles that touch the walls of a glass are slowed in their travel upwards. Bubbles in the centre of the glass are, however, free to rise to the surface, and thus form a rising column of bubbles. The rising bubbles create a current by the entrainment of the surrounding fluid. As beer rises in the center, the beer near the outside of the glass falls. This downward flow pushes the bubbles near the glass towards the bottom. Although the effect occurs in any liquid, it is particularly noticeable in any dark nitrogen stout, as the drink combines dark-coloured liquid and light-coloured bubbles
Tuesday, June 19, 2007
Oh Say, Can You See?
Today’s lesson is about who really discovered America. I remember when I was younger a friend of mine came to me with this question.
- Do you know who discovered America?
Obviously it’s was trick … I just knew it, but I still answered “Christopher Columbus”!!!
Then my friend replied : “No, it is Amerigo Vespucci”. He had to be wrong. So I told him that I trusted my history teacher more than I trust him on this subject, but then he told me something that I couldn’t deny … it’s been discovered by Christopher Columbus, how come isn’t called Columbia ?
I was in big trouble. The closest thing to Internet at the time was my father; he was the one with all the answer and even him couldn’t answered my question properly. A few years later I had the chance to read a bit about my good friend Amerigo. Now I don’t recall exactly what the books was about (in fact I cant even remember what I did yesterday), so I’ve grab this from wikipedia to explain my point :
http://en.wikipedia.org/wiki/Amerigo_Vespucci
In 1507, Martin Waldseemüller produced a world map on which he named the new continent "America" after Vespucci's first name, Amerigo. In an accompanying book, Waldseemüller published one of the Vespucci accounts, which led to criticism that Vespucci was trying to usurp Christopher Columbus's glory. However, the rediscovery in the 18th century of other letters by Vespucci has led to the view that the early published accounts were fabrications, not by Vespucci, but by others.
Soooooooo, it wasn’t Amerigo that discovered America. Still I find very interesting to at least know where the name is coming from.
So if a you ever encounter someone that ask you the same question, you will know what to answer : Viking (Gunnbjörn Ulfsson first sighted Greenland in the early 900s)
- Do you know who discovered America?
Obviously it’s was trick … I just knew it, but I still answered “Christopher Columbus”!!!
Then my friend replied : “No, it is Amerigo Vespucci”. He had to be wrong. So I told him that I trusted my history teacher more than I trust him on this subject, but then he told me something that I couldn’t deny … it’s been discovered by Christopher Columbus, how come isn’t called Columbia ?
I was in big trouble. The closest thing to Internet at the time was my father; he was the one with all the answer and even him couldn’t answered my question properly. A few years later I had the chance to read a bit about my good friend Amerigo. Now I don’t recall exactly what the books was about (in fact I cant even remember what I did yesterday), so I’ve grab this from wikipedia to explain my point :
http://en.wikipedia.org/wiki/Amerigo_Vespucci
In 1507, Martin Waldseemüller produced a world map on which he named the new continent "America" after Vespucci's first name, Amerigo. In an accompanying book, Waldseemüller published one of the Vespucci accounts, which led to criticism that Vespucci was trying to usurp Christopher Columbus's glory. However, the rediscovery in the 18th century of other letters by Vespucci has led to the view that the early published accounts were fabrications, not by Vespucci, but by others.
Soooooooo, it wasn’t Amerigo that discovered America. Still I find very interesting to at least know where the name is coming from.
So if a you ever encounter someone that ask you the same question, you will know what to answer : Viking (Gunnbjörn Ulfsson first sighted Greenland in the early 900s)
Monday, June 18, 2007
Freezing Rain
I don’t have a lot of time, so today’s fact will be a short one. I was looking to talk about another subject while I found this: Pure water actually freezes a -42C (-43.6F). This will only happen if no nucleators (like dust) are presents. But since dusts (and other nucleators) are pretty much present everywhere in the environment, water normally freeze a 0C.
Friday, June 15, 2007
Jingle bells, Jingle bells …
Today’s fact regards the number of Inuit words for snow. A popular belief is that Eskimo as more than an hundred words for snow. In the Central Alaskan Yup'ik language, there is less than 25 words to describe snow.
Well, this might still seem a lot, but in English, there’s at least 40 words including berg, frost, glacier, hail, shush, flurry, sleet. Now you can argue that all of this words describe a different state/form of frozen water, but this is exactly the same for the Yup’ik language.
Well, this might still seem a lot, but in English, there’s at least 40 words including berg, frost, glacier, hail, shush, flurry, sleet. Now you can argue that all of this words describe a different state/form of frozen water, but this is exactly the same for the Yup’ik language.
Thursday, June 14, 2007
Nothing but blue sky …
Why is the sky blue? The short answer is because the light from the sun is diffused in the atmosphere. But why blue? First we need to define the term scattering. Light Scattering is when the light is forced to deviate from a straight trajectory by one or more localized non-uniformities in the medium through which it passes.
The sky appears blue because, air scatters short-wavelength light in preference to longer wavelengths. Blue have the shortest wavelength of the color spectrum, while red have the longest one.
This explains the blue sky, but what about the red one. During daytime, about 25% of the lights is scattered in the atmosphere. Near sunrise and sunset, most of the light we see comes in nearly tangent to the Earth's surface, so that the light's path through the atmosphere is so long that much of the blue and even yellow light is scattered out, leaving only the red wavelength.
The sky appears blue because, air scatters short-wavelength light in preference to longer wavelengths. Blue have the shortest wavelength of the color spectrum, while red have the longest one.
This explains the blue sky, but what about the red one. During daytime, about 25% of the lights is scattered in the atmosphere. Near sunrise and sunset, most of the light we see comes in nearly tangent to the Earth's surface, so that the light's path through the atmosphere is so long that much of the blue and even yellow light is scattered out, leaving only the red wavelength.
Wednesday, June 13, 2007
Lighter than Light
By definition, a black hole is an object with a gravitational field so powerful that a region of space becomes cut off from the rest of the universe – no matter or radiation, including visible light, that has entered the region can ever escape.
Now, in school we learn that the gravitational force (F) is calculated by F = Gmn / r*r where G is the universal gravitational constant, m the mass of the first object, n the mass of the second object and r the distance between the object.
We also learn in school that light as no mass. This had me thinking … if light as no mass, it shouldn’t be attracted by the gravitational field of a black hole. It appears that Einstein thought of that before me. Einstein proposed in is general theory of relativity that mass and radius of an object (its compactness) actually curves space-time. The stronger the gravitational field of an object, the more the space around the object is curved. In other words, straight lines are no longer straight if exposed to a strong gravitational field; instead, they are curved. Since light ordinarily travels on a straight-line path, light follows a curved path if it passes through a strong gravitational field. This is what is meant by "curved space," and this is why light becomes trapped in a black hole.
Now, in school we learn that the gravitational force (F) is calculated by F = Gmn / r*r where G is the universal gravitational constant, m the mass of the first object, n the mass of the second object and r the distance between the object.
We also learn in school that light as no mass. This had me thinking … if light as no mass, it shouldn’t be attracted by the gravitational field of a black hole. It appears that Einstein thought of that before me. Einstein proposed in is general theory of relativity that mass and radius of an object (its compactness) actually curves space-time. The stronger the gravitational field of an object, the more the space around the object is curved. In other words, straight lines are no longer straight if exposed to a strong gravitational field; instead, they are curved. Since light ordinarily travels on a straight-line path, light follows a curved path if it passes through a strong gravitational field. This is what is meant by "curved space," and this is why light becomes trapped in a black hole.
Tuesday, June 12, 2007
Happiness is 22 milliseconds away
Yesterday, I friend of mine ask me if I knew why vendor where insisting that a lower refresh rate on LCD computer monitor was a necessity. He was arguing that a 8ms refresh rate should be more then enough since the human eyes only see 24 images per second (1/24 so 1 image by 42ms). Above that, CRT monitor have typically 22-28 ms refresh rate and the image is crystal clear.
He had a good point. So I did my homework and I found the difference. Each pixel in a CRT emits most of the light in under 1ms. So if you have a 22ms monitor, each pixel need 23 ms (22ms refresh rate + 1ms to emit the light) to change state. In a LCD, will emits light for a much longer type … nearly 20ms. So if you add this to the refresh rate of an old LCD (between 12 to 25) you can have a display time of 45ms … which is way over the 42ms baseline.
This explain why old LCD where kind of blurry when playing a movie. Nowadays LCD have a much better refresh rate, between 2 to 8. But again, this add up to 22ms to 28ms for a whole cycle which is more closer to the average CRT monitor.
He had a good point. So I did my homework and I found the difference. Each pixel in a CRT emits most of the light in under 1ms. So if you have a 22ms monitor, each pixel need 23 ms (22ms refresh rate + 1ms to emit the light) to change state. In a LCD, will emits light for a much longer type … nearly 20ms. So if you add this to the refresh rate of an old LCD (between 12 to 25) you can have a display time of 45ms … which is way over the 42ms baseline.
This explain why old LCD where kind of blurry when playing a movie. Nowadays LCD have a much better refresh rate, between 2 to 8. But again, this add up to 22ms to 28ms for a whole cycle which is more closer to the average CRT monitor.
Monday, June 11, 2007
The Forbidden Fruit
I guess nobody will be surprised to read that a Tomato is a fruit. I had this discussion with my girlfriend daughter a short while ago. I explained to her that fruit grows in tree and bushes while most of the veggies grow underground. So a tomato is a fruits since it grows in a plant … but then it occurs to me: what about sweet pepper (bell pepper). I made a few research and I found that it’s also a fruit.
I found that a lot of vegetable are in fact fruits by definition. This include: cucumbers, tomato, peas, beans, corn, and eggplant.
So next time you order a Fruit Salad, be sure to ask what in it !
I found that a lot of vegetable are in fact fruits by definition. This include: cucumbers, tomato, peas, beans, corn, and eggplant.
So next time you order a Fruit Salad, be sure to ask what in it !
Friday, June 8, 2007
Seize the Day!
I always wonder why doctors (mostly in TV show, because I never saw a real case) were turning the patient on the side during a seizure. It appears that by doing so, this open the airway and allow secretions to drain (so basically it will help prevent the patient from choking).
I was once told that we should put something (like a comb) in the patient mouth to prevent him to bite is tongue. It appears that it would in fact not be a good thing to do.
Other first aid tips are :
- Prevent further injury. Place something soft under the head, loosen tight clothing, and clear the area of sharp or hard objects.
- Do not force objects into the person’s mouth.
- Do not restrain the person’s movements unless they place him or her in danger.
http://www.epilepsyfoundation.org/answerplace/Medical/seizures/types/genConvulsive/seizuretonic.cfm
I was once told that we should put something (like a comb) in the patient mouth to prevent him to bite is tongue. It appears that it would in fact not be a good thing to do.
Other first aid tips are :
- Prevent further injury. Place something soft under the head, loosen tight clothing, and clear the area of sharp or hard objects.
- Do not force objects into the person’s mouth.
- Do not restrain the person’s movements unless they place him or her in danger.
http://www.epilepsyfoundation.org/answerplace/Medical/seizures/types/genConvulsive/seizuretonic.cfm
Thursday, June 7, 2007
Elephants hear through their feet
A Stanford University team as discovered that elephant may hear through their feet. That right, the animal with the biggest ears can also use their feet to hear. Soft skin of the foot acts like a drum head to sense vibrations which travel from the toe nails to the ear by bone conduction. Foot stomping and low-frequency rumbling generated by one group of elephants are picked up by another group far away.
Researcher recorded the made by the elephants when a predator was around the herd. The later replay the recording in the ground, by sending the correct seismic vibration to find out that the elephants hearing it start acting as if a predator was near.
Researcher recorded the made by the elephants when a predator was around the herd. The later replay the recording in the ground, by sending the correct seismic vibration to find out that the elephants hearing it start acting as if a predator was near.
Wednesday, June 6, 2007
Don’t forget to put chocolate on your grocery list!!!
Scientists from the Salk Institute have discover that the chemical epicatechin help to boost the memory of mice. This chemical is found in grapes, blueberries, tea and of course chocolate. Its also seems to boost the blood flow in certain parts of the brain.
Now the real question is: how do you test the memory of a mouse ? Obviously you cant ask it : “Do you remember last week when we share a piece of blue cheese …”. I guess that you can make them go into a maze, repeat the operation until the mouse know exactly the way, calculate the amount of time needed to the mouse to forget the way through the maze, fat her up with chocolate and wait the same amount of time to see if this time she will remember (yeah my imaginary mouse is a female).
I guess my point is that checking a product cure cancer is more maybe a bit more straightforward to accurately test whether or not chocolate is good for you.
Now the real question is: how do you test the memory of a mouse ? Obviously you cant ask it : “Do you remember last week when we share a piece of blue cheese …”. I guess that you can make them go into a maze, repeat the operation until the mouse know exactly the way, calculate the amount of time needed to the mouse to forget the way through the maze, fat her up with chocolate and wait the same amount of time to see if this time she will remember (yeah my imaginary mouse is a female).
I guess my point is that checking a product cure cancer is more maybe a bit more straightforward to accurately test whether or not chocolate is good for you.
Tuesday, June 5, 2007
Resistance is futile
Today I intended to verify a citation from Star Trek: The Motion Picture. V'ger (SPOILER : If you have been living in a cavern for the last 28 years, don’t read this post) which is revealed to be the unmanned scientific probe Voyager 6, wanted to destroy the human race, which he refer as the carbon life-based.
I wanted to see how much this is true, since the most common citation are about that our body is constituted of about 70% of water. Obviously there’s no carbon in water so I was really wandering about this carbon thing.
It appears that carbon is a base element of our DNA and RNA. It’s also part of sugars, celluloses, chitins, alcohols, fats, aromatic esters, alkaloids, antibiotics, amino acids and proteins.
Another interesting fact is that the fat free mass of a human body is made of 70% of water. Note that the fat free mass is the total mass minus the total fat weigh. Since a normal man should have between 13 and 17 percent fat and a female should be composed of between 20 and 25 percent fat the real percentage of water in the human body should be closer to 58%.
I wanted to see how much this is true, since the most common citation are about that our body is constituted of about 70% of water. Obviously there’s no carbon in water so I was really wandering about this carbon thing.
It appears that carbon is a base element of our DNA and RNA. It’s also part of sugars, celluloses, chitins, alcohols, fats, aromatic esters, alkaloids, antibiotics, amino acids and proteins.
Another interesting fact is that the fat free mass of a human body is made of 70% of water. Note that the fat free mass is the total mass minus the total fat weigh. Since a normal man should have between 13 and 17 percent fat and a female should be composed of between 20 and 25 percent fat the real percentage of water in the human body should be closer to 58%.
Monday, June 4, 2007
Everything is not Black & White
What is black? Most people will say that it is the absence of all colors. This is a half truth. The real definition would be that it doesn’t reflect light of the visible spectrum. Some will call me a purist, but the distinction is important. Especially when you think about the next question: What is white? Now, after reading this, a five years old could figure out that the answer is that white reflect all the light of the visible spectrum.
But what about our good old definition: White is a combination of all colors & Black is the absence of all color. Well its all depend of the system your are referring to. This is true is the additive color system. In the subtractive color system, it is the opposite (try to mix paint of all colors together, you will get Black). This difference would be a big deal if our primary reference system would be the additive one. But if you ask a kid what are the primary color, he will answer yellow, red & blue (which is not even correct, the real colors are yellow, magenta and cyan). Theses colors are the primary color of the subtractive system. In the additive system, the primary colors are red, blue and green (like for a television).
Now what about Gray? We often hear those grays are note a color, but a shade or a tint. Gray is a color … but it’s also a shade. A tint is a mix of a color and white. A shade is a mix of a color and black. Since White is considerate as a color (but not black), Grays are then a mix of a color (white) and black. So they are a shade.
But what about our good old definition: White is a combination of all colors & Black is the absence of all color. Well its all depend of the system your are referring to. This is true is the additive color system. In the subtractive color system, it is the opposite (try to mix paint of all colors together, you will get Black). This difference would be a big deal if our primary reference system would be the additive one. But if you ask a kid what are the primary color, he will answer yellow, red & blue (which is not even correct, the real colors are yellow, magenta and cyan). Theses colors are the primary color of the subtractive system. In the additive system, the primary colors are red, blue and green (like for a television).
Now what about Gray? We often hear those grays are note a color, but a shade or a tint. Gray is a color … but it’s also a shade. A tint is a mix of a color and white. A shade is a mix of a color and black. Since White is considerate as a color (but not black), Grays are then a mix of a color (white) and black. So they are a shade.
Friday, June 1, 2007
Show me the finger!
A recently read a article about how the lengths of the index and the ring fingers can be used to predicts SAT result, aggressive behavior, homosexuality, risk of a heart attack, sexual appetite and many others.
In fact it’s all a matter of testosterone and estrogen. The number of testosterone in the early stage of development seems to affect many aspect of our life. This also affects the lengths of our finger. The normal male pattern is to have is ring finger slightly longer that the index. For the women, both fingers are the same length.
So basically men with the female pattern are more likely to become a scientist and to be in touch with there feminine side. The estrogen is believe to causes the right side of the brain to develop, which is responsible for spatial and analytical skills.
On the opposite, female with male pattern will have a bigger sexual appetite and will be more aggressive.
In conclusion, the longer the ring finger the most testosterone you had. So don’t be shy … show me your finger.
In fact it’s all a matter of testosterone and estrogen. The number of testosterone in the early stage of development seems to affect many aspect of our life. This also affects the lengths of our finger. The normal male pattern is to have is ring finger slightly longer that the index. For the women, both fingers are the same length.
So basically men with the female pattern are more likely to become a scientist and to be in touch with there feminine side. The estrogen is believe to causes the right side of the brain to develop, which is responsible for spatial and analytical skills.
On the opposite, female with male pattern will have a bigger sexual appetite and will be more aggressive.
In conclusion, the longer the ring finger the most testosterone you had. So don’t be shy … show me your finger.
Thursday, May 31, 2007
Jiminy Cricket was a weatherman
Did you know that cricket can tell you what the current temperature is? According to the Dolbear’s Law, the number of cricket chirps by minute is in direct relation with the ambient temperature.
The formula is Temperature in Fahrenheit = 50 + (Number of chirps per minutes – 40) / 4.
In Celsius the formula is Temperature in Celsius = 10 + (Number of chirps per minutes – 40) / 7.
But don’t throw your thermometer away just yet, this formula only apply to snowy tree cricket which is not the most common one. The formula may apply to others of the 900 species of crickets, but may not be as accurate.
The formula is Temperature in Fahrenheit = 50 + (Number of chirps per minutes – 40) / 4.
In Celsius the formula is Temperature in Celsius = 10 + (Number of chirps per minutes – 40) / 7.
But don’t throw your thermometer away just yet, this formula only apply to snowy tree cricket which is not the most common one. The formula may apply to others of the 900 species of crickets, but may not be as accurate.
Wednesday, May 30, 2007
States of Matter : How many are they ?
A common answer would be 3: Solids, Liquids and Gases. This answer would not only be wrong but only cover a small part of the universe matter. Plasma is the type of matter that is the most common among the universe. A plasma is typically a gas at a very high temperature (think about a star). A candle flame would be called a cold plasma (because of the small fraction of the gas molecules that are ionized, but this is maybe too much detail).
So there’s a 4 states of matter. WRONG!!!! There’s also Quark-Gluon plasma (which as only existed for about 30 microseconds during the big-bang), Bose-Einstein condensate and Fermionic condensate (both states are near absolute zero), Strange Matter (the name is almost self explanatory; a mater composed from three types of quarks: up, down and strange) supersolid and superliquid (both can be flow without friction … I wonder if that also apply to superman) and finally string-net liquids.
Now where up to 11 states. But wait there is more !!! There’s also Quantum Hall and Quantum Spin Hall, Degenerate matter, Weakly symmetric matter, Strongly symmetric matter, Neutronium, Electron-degenerate matter, Colloid, Supercritical fluid, Liquid Crystal, Crystaline Solid, Amophous Sold and Gravitational Singularity.
So the answer would be 24 … lets see what Jack Bauer can do about this.
So there’s a 4 states of matter. WRONG!!!! There’s also Quark-Gluon plasma (which as only existed for about 30 microseconds during the big-bang), Bose-Einstein condensate and Fermionic condensate (both states are near absolute zero), Strange Matter (the name is almost self explanatory; a mater composed from three types of quarks: up, down and strange) supersolid and superliquid (both can be flow without friction … I wonder if that also apply to superman) and finally string-net liquids.
Now where up to 11 states. But wait there is more !!! There’s also Quantum Hall and Quantum Spin Hall, Degenerate matter, Weakly symmetric matter, Strongly symmetric matter, Neutronium, Electron-degenerate matter, Colloid, Supercritical fluid, Liquid Crystal, Crystaline Solid, Amophous Sold and Gravitational Singularity.
So the answer would be 24 … lets see what Jack Bauer can do about this.
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