
Friday, August 13, 2010
sound affecting fishes survival

cadmium

In the 1950s and 1960s industrial exposure to cadmium was high, but as the toxic effects of cadmium became apparent, industrial limits on cadmium exposure have been reduced in most industrialized nations and many policy makers agree on the need to reduce exposure further. While working with cadmium it is important to do so under a fume hood to protect against dangerous fumes. Silver solder, for example, which contains cadmium, should be handled with care. Serious toxicity problems have resulted from long-term exposure to cadmium plating baths.
Buildup of cadmium levels in the water, air, and soil has been occurring particularly in industrial areas. Environmental exposure to cadmium has been particularly problematic in Japan where many people have consumed rice that was grown in cadmium contaminated irrigation water. This phenomenon is known under the name itai-itai disease.
Food is another source of cadmium. Plants may only contain small or moderate amounts in non-industrial areas, but high levels may be found in the liver and kidneys of adult animals.
Cigarettes are also a significant source of cadmium exposure. Although there is generally less cadmium in tobacco than in food, the lungs absorb cadmium more efficiently than the stomach.
Aside from tobacco smokers, people who live near hazordous waste sites or factories that release cadmium into the air have the potential for exposure to cadmium in air. However, numerous state and federal regulations in the united states control the amount of cadmium that can be released to the air from waste sites and incinerators so that properly regulated sites are not hazardous. The general population and people living near hazardous waste sites may be exposed to cadmium in contaminated food, dust, or water from unregulated releases or accidental releases. Numerous regulations and use of pollution controls are enforced to prevent such releases.
how is this chemical used now?
In taped remarks to be delivered Tuesday in Hong Kong, the chairwoman of the U.S. Consumer Product Safety Commission urged other countries to ensure that manufacturers do not substitute cadmium, antimony or barium in place of lead in children's products. this is from China, but what about in the states, in WallMart?
an article quoted by salon.com. "
Wal-Mart said Wednesday it is pulling an entire line of Miley Cyrus-brand necklaces and bracelets from its shelves after tests performed for The Associated Press found the jewelry contained high levels of the toxic metal cadmium.
In a statement issued three hours after AP's initial report of its findings, Wal-Mart said it would remove the jewelry while it investigates. The statement was issued along with Cyrus and Max Azria, the designer that developed the jewelry for the 17-year-old "Hannah Montana" star.
In the statement, Wal-Mart said that while the jewelry is not intended for children, "it is possible that a few younger consumers may seek it out in stores."
"We are removing all of the jewelry from sale while we investigate its compliance with our children's jewelry standard," Wal-Mart said.
Cadmium in jewelry is not known to be dangerous if the items are simply worn. Concerns come when youngsters bite or suck on the jewelry, as many children are apt to do.
Long-term exposure to cadmium can lead to bone softening and kidney failure. It is also a known carcinogen, and research suggests that it can, like lead, hinder brain development in the very young.
Testing of 61 samples bought by AP reporters across the country from the Miley Cyrus line and from an unrelated line of bracelet charms showed that 59 of the pieces contained at least 5 percent cadmium by weight, with 53 of those measuring 10 percent or higher. The packaging on both lines of jewelry said they were made in China; all were bought for $6 or less.
In its statement, Wal-Mart did not say whether it would also remove the bracelet charms.
Wal-Mart Stores Inc. received test results in February showing cadmium in these jewelry lines but had continued selling the items.
The chain said last month that it has begun requiring suppliers to prove their products contain little cadmium, or else Wal-Mart would not accept the items. But Wal-Mart said at the time that testing products already on its shelves would be too difficult.
Wal-Mart did not say how many of pieces of the Miley Cyrus pieces it has sold."
Wednesday, August 11, 2010
global warming

Global warming is when the earth heats up (the temperature rises). It happens when greenhouse gases (carbon dioxide, water vapor, nitrous oxide, and methane) trap heat and light from the sun in the earth’s atmosphere, which increases the temperature. This hurts many people, animals, and plants. Many cannot take the change, as most animals and plants, are adept to certain temperatures. Global warming also causes hibernating animals to wake up earlier than usual, which can cause a decline in numbers. several species of marmots, chipmunks and brown bears have been noticed that they have shortened hibernation period, and in some cases, they do not hibernate at all.
'global warming' usually comes with 'greenhouse gases', but what is is, actually?The greenhouse effect is when the temperature rises because the sun’s heat and light is trapped in the earth’s atmosphere. This is like when heat is trapped in a car. On a very hot day, the car gets hotter when it is out in the parking lot. This is because the heat and light from the sun can get into the car, by going through the windows, but it can’t get back out. This is what the greenhouse effect does to the earth. The heat and light can get through the atmosphere, but it can’t get out. As a result, the temperature rises.
Global warming is affecting many parts of the world. Global warming makes the sea rise, and when the sea rises, the water covers many low land islands. This is a big problem for many of the plants, animals, and people on islands. The water covers the plants and causes some of them to die. When they die, the animals lose a source of food, along with their habitat. Although animals have a better ability to adapt to what happens than plants do, they may die also. When the plants and animals die, people lose two sources of food, plant food and animal food. They may also lose their homes. As a result, they would also have to leave the area or die. This would be called a break in the food chain, or a chain reaction, one thing happening that leads to another and so on.
The oceans are affected by global warming in other ways, as well. Many things that are happening to the ocean are linked to global warming. One thing that is happening is warm water, caused from global warming, is harming and killing algae in the ocean.
Algae is a producer that you can see floating on the top of the water. (A producer is something that makes food for other animals through photosynthesis, like grass.) This floating green algae is food to many consumers in the ocean. (A consumer is something that eats the producers.) One kind of a consumer is small fish. There are many others like crabs, some whales, and many other animals. Fewer algae is a problem because there is less food for us and many animals in the sea.
Global warming is doing many things to people as well as animals and plants. It is killing algae, but it is also destroying many huge forests. The pollution that causes global warming is linked to acid rain. Acid rain gradually destroys almost everything it touches. Global warming is also causing many more fires that wipe out whole forests. This happens because global warming can make the earth very hot. In forests, some plants and trees leaves can be so dry that they catch on fire.
Monday, August 9, 2010
static electricity
an example of static electricity at work would be getting zapped by your own door knob.
As you walk across a carpet, electrons move from the rug to you. Now you have extra electrons and a negative static charge. Touch a door knob and ZAP! The door knob is a conductor. The electrons jump from you to the knob, and you feel the static shock.
in temperate countries, they usually only notice static electricity in the winter when the air is very dry. During the summer, the air is more humid. The water in the air helps electrons move off you more quickly, so you can not build up as big a static charge.
For example, if you rub a glass rod with a silk cloth or if you rub a piece of amber with wool, the glass and amber will develop a static charge that can attract small bits of paper or plastic.
To understand what is happening when your body or a glass rod develops a static charge, you need to think about the atoms that make up everything we can see. All matter is made up of atoms, which are themselves made up of charged particles. Atoms have a nucleus consisting of neutrons and protons. They also have a surrounding "shell" that is made up electrons. Typically, matter is neutrally charged, meaning that the number of electrons and protons are the same. If an atom has more electrons than protons, it is negatively charged. If it has more protons than electrons, it is positively charged.
The following table shows you the triboelectric series for many materials you find around the house. Positive items in the series are at the top, and negative items are at the bottom:
Friday, August 6, 2010
anal fissure

Wednesday, August 4, 2010
sonicboom

a sonic boom is an impulsive noise similar to thunder. it is caused by an object moving faster than sound, about 750 miles per hour at sea level. an aircraft traveling through the atmosphere continuously produces air-pressure waves similar to the water waves caused by a ship's bow. when the aircraft exceeds the speed of sound, these pressure waves combine and form shock waves which travel forward from the generation or "release" point.
As an aircraft flies at supersonic speeds it is continually generating shock waves, dropping sonic boom along its flight path, similar to someone dropping objects from a moving vehicle. From the perspective of the aircraft, the boom appears to be swept backwards as it travels away from the aircraft. If the plane makes a sharp turn or pulls up, the boom will hit the ground in front of the aircraft.
the sonic boom happens when the build-up of pressure is released, this makes an extremely loud sound, this is the sonic boom.
(There are not one, but two types of booms: N-waves and U-waves. The N-wave is generated from steady flight conditions, and its pressure wave is shaped like the letter "N." N-waves have a front shock to a positive peak overpressure which is followed by a linear decrease in the pressure until the rear shock returns to ambient pressure. The U-wave, or focused boom, is generated from maneuvering flights, and its pressure wave is shaped like the letter "U." U-waves have positive shocks at the front and rear of the boom in which the peak overpressures are increased compared to the N-wave.)
sonic boom clip _here_
centroiles

first law

that is Newton's first law of motion. But what does it mean?
This law states that if theresultant force(the vector sum of all forces acting on an object) is zero, then the velocity of the object is constant. Consequently, an object will always stay at rest unless an unbalanced is acted upon it, and a moving object will not change its velocity unless an unbalanced force is acted upon it.an unbalanced force is when a number of forces act on a body simultaneously and the resultant of these forces is zero then the forces are said to be balanced. Equal forces acting on an object in opposite direction. Is when two forces are applied on an objectin a different direction.
There are many exellent examples to depict Newton's first law of motion at work, such as when a pilot changes the throttle of the aeroplane, it shows 'a moving object will not change its velocity unless an unbalanced force is acted upon it. similarly, the first law can be shown as something as simple as kicking a soccer ball or even sliding a book on the floor.
subconciously, Newton's first law is seen everyday.
Wednesday, July 21, 2010
top 3 KILLER diseases
heart disease, it is the cause for some 1.5 lives( in America alone ) every single year. caused by fatty plague build-up in the artery. the likely cause for this is a bad diet of oily and high-cholesterol foods. shockingly, almost half of the people who die from heart disease do not have any symptoms to start with, they just continue with their lives until it happens. for those who are lucky and have symptoms to warn them, this is what is happening. the artery is blocked. so the heart corrects It by lowering its demands, by first trying to tell u through a sharp pain in your chest. as the contractions of the heart weakens, and heart beat becomes irregular, nausea and cold sweat will start. if this continues, parts of the heart shut down. when the heart does not get enough blood, that part will die, then... HEART ATTACK!!!
cancer, 1/3 is poor lifestyle, 1/3 is smoking, and the final 1/3 is by inevitable genetic factors. what is cancer anyway, usually thought to be a disease only affecting the old and weak, but today it affects 25% of all America's population. it is caused when our own cells mutate to attack the very body it was made to protect. it only takes one cell. this cell will divide and multiply at an abnormally fast rate, it penetrates previously, imperveable tissue. if detected and cured early, it can allow the victim to live. But if the mutated cell continues with the rapid division and the destruction of the body, the victim will eventually die.
lastly, stroke. frightening in a way that u know your brain is failing you and you are 100% aware of the alteration of your own brain. in the case of a stroke, if you don't die, you will have to live with a disability. with the disability, which could last for years, you will not be able to take care of yourself in the slightest way at all. the possibility of this, 20%. hemorrhage is a weakened artery wall is the usual cause for a stroke. it is swift, without warning, and does the most damage, (if the victim actually lives through it). stroke is more likely to be expected by the old, over 50, this kind of stroke is swift. half your face sags, speech is slurred. but post symptoms will be loss of conscience, even if it is only for a couple of minutes. mental confusion and weakening limbs follow. a rich saturated fat diet will result in a higher stroke chance.
Tuesday, July 20, 2010
Down sydromne
Down syndrome is caused by the translocation trisomy of the 21st chromosone. when this hapeens, the 21st chromosone attaches itself to another chromosone, which is usually 14. If the resulting sperm or ovum receives a chromosome 14 (or another chromosome), with a piece of chromosome 21 attached and retains the chromosome 21 that lost a section due to translocation, then the reproductive cells contain the normal or balanced amount of chromosome 21. While there will be no Down syndrome associated characteristics exhibited, the individual who develops from this fertilized egg will be a carrier of Down syndrome. Genetic counseling can be sought to find the origin of the translocation.
when?
Most of the time, the occurrence of Down syndrome is due to a random event that occurred during formation of the reproductive cells, the ovum or sperm. Down syndrome is not attributable to any behavioral activity of the parents or environmental factors. Regardless of maternal age, there will be 1 in 100 baby's born with down syndrome.
whats wrong?
though there are actually many synptoms one may have when he/she has down syndrome. though all those affected may not suffer every single synptom but there are a few more common ones: decreased muscle tone at birth, asymmetrical or odd-shaped skull, round head with flat area at the back of the head, small skull, slanting eyes, small mouth with protruding tongue, broad short hands, single crease on the palm, retarded growth and development, delayed mental and social skills (mental retardation).
any cure???
sadly, there are no cures for down syndrome, because it starts from the chromosones. Thus all doctors can do is to curb the symptoms, through means like surgery, medication, counselling and regular check-ups and screenings. of all, regular check-ups are the most important. people with down syndrome have more chance of life threatening diseases.
conclusion???
Down syndrome is good in its own ways. people with this case should noy be seen as retards, jokes or sad cases.
Friday, July 16, 2010
stem cells
Cancer and stem cell biology researchers at the University of Colorado are launching the nation’s first program focused on identifying and testing drugs that target and destroy cells thought to be at the root of cancer — cancer stem cells (CSCs).
chromosones
A chromosome is an organized structure of DNA and protein that is found in cells. It is a single piece of coiled DNA containing many genes and redulatory elements. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions. The word chromosome comes from the Greek word (chroma, color) and (soma, body) due to their property of being very strongly stained by particular dyes.
having extra chromosones is usually more negative than it is positive. our cells are made to check for 23 cells and not 24, thus leading to many problems such as sterility, and with an extra chromosone, down syndrome will occur.
down syndrome is the only trisomy that last more than 2-3 years, other than down syndrome, there are others as well, such as 'Edward's Syndrome', 'Patau Syndrome', and derived fron the different chromosone pairs with an extra.
Edwards syndrome is very rare, only present in one every five-thousand births. the chances increase if the mother is above 30.