Name: Norman Anthony Aguero
Currently a student at FIU. My major is chemistry and my minor is physics. My goal is to hopefully earn a Ph.D. in physical organic chemistry.
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| Gluon | |
| Composition: | Elementary particle |
|---|---|
| Family: | Boson |
| Group: | Gauge boson |
| Interaction: | Strong interaction |
| Symbol: | g |
| No. of types: | 8 |
| Mass: | 0 |
| Electric charge: | 0[1] |
| Color charge: | nonzero |
| Spin: | 1 |
In particle physics, gluons (from glue + -on) are elementary particles that cause quarks to interact, and are indirectly responsible for the binding of protons and neutrons together in atomic nuclei.
In technical terms, they are vector gauge bosons that mediate strong color charge interactions of quarks in quantum chromodynamics (QCD). Unlike the neutral photon of quantum electrodynamics (QED), gluons themselves participate in strong interactions. The gluon has the ability to do this as it carries the color charge and so interacts with itself, making QCD significantly harder to analyze than QED.
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The gluon is a vector boson; like the photon, it has a spin of 1. While massive spin-1 particles have three polarization states, massless gauge bosons like the gluon have only two polarization states because gauge invariance requires the polarization to be transverse. In quantum field theory, unbroken gauge invariance requires that gauge bosons have zero mass (experiment limits the gluon's mass to less than a few MeV). The gluon has negative intrinsic parity and zero isospin. It is its own antiparticle.
Unlike the single photon of QED or the three W and Z bosons of the weak interaction, there are eight independent types of gluon in QCD.
This may be difficult to understand intuitively. Quarks may carry three types of color charge; antiquarks carry three types of anticolor. Gluons may be thought of as carrying both color and anticolor or as describing how quark color changes during interactions, so because gluons carry nonzero color charge it may be thought that there are only six gluons.
Technically, QCD is a gauge theory with SU(3) gauge symmetry. Quarks are introduced as spinor fields in Nf flavours, each in the fundamental representation (triplet, denoted 3) of the colour gauge group, SU(3). The gluons are vector fields in the adjoint representation (octets, denoted 8) of colour SU(3). For a general gauge group, the number of force-carriers (like photons or gluons) is always equal to the dimension of the adjoint representation. For the simple case of SU(N), the dimension of this representation is N2−1. Main article: Colour confinement
Since gluons themselves carry color charge (again, unlike the photon which is electrically neutral), they participate in strong interactions. These gluon-gluon interactions constrain color fields to string-like objects called "flux tubes", which exert constant force when stretched. Due to this force, quarks are confined within composite particles called hadrons. This effectively limits the range of the strong interaction to 10-15 meters, roughly the size of an atomic nucleus.
Gluons also share this property of being confined within hadrons. One consequence is that gluons are not directly involved in the nuclear forces. The force mediators for these are other hadrons called mesons.
Although in the normal phase of QCD single gluons may not travel freely, it is predicted that there exist hadrons which are formed entirely of gluons — called glueballs. There are also conjectures about other exotic hadrons in which real gluons (as opposed to virtual ones found in ordinary hadrons) would be primary constituents. Beyond the normal phase of QCD (at extreme temperatures and pressures), quark gluon plasma forms. In such a plasma there are no hadrons; quarks and gluons become free particles.
The first direct experimental evidence of gluons was found in 1979 when three-jet events were observed at the electron-positron collider called PETRA at DESY in Hamburg. Quantitative studies of deep inelastic scattering at the Stanford Linear Accelerator Center had established their existence a decade before that.
Experimentally, confinement is verified by the failure of free quark searches. Neither free quarks nor free gluons have ever been observed. Although there have been hints of exotic hadrons, no glueball has been observed either. Quark-gluon plasma has been found recently at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratories (BNL).
I wonder why I'm so musical...
What I do. I've even applied these principles to primary metabolism: the anabolism and catabolism on a molecular level of certain pathways that occur in living cells.
Physical organic chemistry is the study of the interrelationships between structure and reactivity in organic molecules. It can be seen as the study of organic chemistry using tools of physical chemistry such as chemical equilibrium, chemical kinetics, thermochemistry, and quantum chemistry. The term "physical organic chemistry" is commonly attributed to Louis Hammett, who used it as a title for a book in 1940.
The two main themes in physical organic chemistry are structure and reactivity. The study of structure starts from chemical bonding, with special emphasis on the stability of organic molecules due to factors such as steric strain and aromaticity. Other topics in structure include stereochemistry and conformational analysis. Supramolecular structure is also considered in terms of intermolecular forces including hydrogen bonding. Finally, the acid-base chemistry of the molecules is studied in terms of structure, based on resonance and inductive effects and through the use of linear free-energy relations.
The study of reactivity focuses on the mechanisms of organic reactions. It uses chemical kinetics, spectroscopy, isotope effects, and quantum chemistry to determine the sequence of elementary steps involved in a reaction. These elementary steps can be classified in a few major classes: addition, elimination, substitution, and pericyclic reactions. The mechanisms are commonly expressed in terms of "electron pushing" and potential energy surfaces. Another major topic is photochemistry, the effect of light on the reactivity of organic molecules.
Structure and reactivity are both involved in the study of reaction intermediates—the transient species involved in reaction mechanisms. The main types of intermediates of interest are carbocations, carbanions, free radicals, and carbenes. Usually, these intermediates are not isolated, but their presence cab be inferred from stereochemical evidence, spectroscopy, or through the use of chemical traps. In some cases, however, it is possible to isolate these types of molecules at very low temperatures (cryochemistry) or matrix isolation. It is also possible to create specific derivatives that are stabilized through chemical means such as resonance, as in the case of the triphenylmethyl radical.
Loch Ness Monster
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(June 1999, California) Last summer down on Lake Isabella, in the high desert east of Bakersfield, a woman was having trouble with her boat.
No matter how she tried, she just couldn't get her new 22-foot Bayliner to perform. It was sluggish in every maneuver, regardless of the power applied. She tried for an hour to make her boat go, but finally gave up and putted over to a nearby Marina for help. A topside check revealed that everything was in perfect working order. The engine ran fine, the outboard motor pivoted up and down, and the prop was the correct size and pitch. One of the Marina guys jumped in the water to check beneath the boat. He came up almost choking on water, he was laughing so hard. Under the boat, still strapped securely in place, was the trailer. From the PIGS (Poor Innocent Guys Society) Dedicated to Poor Innocent Guys (victims of the wiles of women) and the SLOTHS (Smart Ladies of the House) who put up with them the_big_pig@my-deja.com |
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Lawn Chair Larry
1982 Honorable Mention
Confirmed True by Darwin
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Larry's boyhood dream was to fly. But fates conspired to keep him from his dream. He joined the Air Force, but his poor eyesight disqualified him from the job of pilot. After he was discharged from the military, he sat in his backyard watching jets fly overhead. He hatched his weather balloon scheme while sitting outside in his "extremely comfortable" Sears lawnchair. He purchased 45 weather balloons from an Army-Navy surplus store, tied them to his tethered lawnchair dubbed the Inspiration I, and filled the 4' diameter balloons with helium. Then he strapped himself into his lawnchair with some sandwiches, Miller Lite, and a pellet gun. He figured he would pop a few of the many balloons when it was time to descend. Larry's plan was to sever the anchor and lazily float up to a height of about 30 feet above his back yard, where he would enjoy a few hours of flight before coming back down. But things didn't work out quite as Larry planned. When his friends cut the cord anchoring the lawnchair to his Jeep, he did not float lazily up to 30 feet. Instead, he streaked into the LA sky as if shot from a cannon, pulled by the lift of 42 helium balloons holding 33 cubic feet of helium each. He didn't level off at 100 feet, nor did he level off at 1000 feet. After climbing and climbing, he leveled off at 16,000 feet.
Eventually he gathered the nerve to shoot a few balloons, and slowly descended. The hanging tethers tangled and caught in a power line, blacking out a Long Beach neighborhood for 20 minutes. Larry climbed to safety, where he was arrested by waiting members of the LAPD. As he was led away in handcuffs, a reporter dispatched to cover the daring rescue asked him why he had done it. Larry replied nonchalantly, "A man can't just sit around." The Federal Aviation Administration was not amused. Safety Inspector Neal Savoy said, "We know he broke some part of the Federal Aviation Act, and as soon as we decide which part it is, a charge will be filed." DarwinAwards.com © 1994 - 2008
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Bay Area has first major U.S. study of Morgellons disease
Bay Area researchers are beginning the first major U.S. study into a mystery disease known for its frightening symptoms - among them, open sores and unidentifiable objects poking out of the skin - that doctors have long suspected is all in patients' heads.
The study into Morgellons will start immediately, as Kaiser Permanente contacts Northern California patients who have reported symptoms of the mystery disease in the past 18 months. The research will be funded by the U.S. Centers for Disease Control and Prevention.
Researchers are hoping to come up with a more specific definition of Morgellons and how prevalent it is in the Bay Area, which has one of the largest concentrations of self-reported cases of the disease in the country.
They also hope to determine once and for all whether Morgellons is a psychiatric condition. "The suffering and the impact of this condition on people's lives, whatever you want to label it, what they're experiencing is real," said Michele Pearson, a principal investigator with the CDC. "That's why this agency has decided to look into it in-depth."
The CDC is not yet agreeing that Morgellons is a medical condition, but Pearson said there's no debating that people are ill and need help.
In addition to the skin problems, symptoms of Morgellons include fatigue, confusion and memory problems, joint pain and a sensation of pins and needles or something crawling on the skin.
Many doctors believe that Morgellons is actually a psychiatric condition called delusional parasitosis. They say the filaments that patients report growing out of their skin are actually lint or threads from clothing, and the open sores are caused by patients scratching at skin when they perceive a crawling sensation.
San Francisco resident Pat Miller has been to more than a dozen doctors since he first developed symptoms several years ago. He's been diagnosed with a wide variety of skin conditions, as well as delusional parasitosis, and few doctors have been willing to consider Morgellons.
He said the Kaiser study, no matter the outcome of it, feels like validation of what he's been going through.
"It sounds to me like if they're involving Kaiser in this study and tracing it in a systematic, methodical way, that pretty much means that, yeah, they think there's something going on," Miller said. "I've developed this lack of love for doctors and health care systems. You pretty much have to become your own doctor."
Unofficial reports of Morgellons are becoming more common, said Pearson. The CDC has taken 1,200 calls in the past year from patients who believe they have Morgellons, and at Kaiser, doctors are increasingly frustrated trying to diagnose a condition with no known cause or treatment.
"There are many hypotheses as to what may be causing it, but there is no textbook on this condition," Pearson said. "It's been a very frustrating journey, not just for patients but also for the physicians treating them."
Patients have been reporting Morgellons symptoms to the CDC regularly for the past three or four years, although it's possible the condition has been around for centuries. A South Carolina mom who believes her three children have the illness found a reference to a similar disease in a 1674 medical study. The disease was called Morgellons in 1674, and modern-day sufferers adopted the name.
The CDC does not officially report cases of Morgellons. The nonprofit Morgellons Research Foundation says that more than 10,000 families in the United States have registered with the Web site, claiming at least one family member has the disease.
About 24 percent of registered families are in California, and the Bay Area is one of several hot spots in the country. The research foundation estimates that 150 to 500 people in Northern California have Morgellons.
The Kaiser study will perform medical exams - including dermatological tests, blood analysis and psychiatric evaluations - at offices in Oakland. Researchers hope to carefully examine skin biopsies and any fibers or other materials that patients report growing out of their skin.
"This is a descriptive study. There are no hypotheses to be tested," said Joe Selby, director of Kaiser's Northern California division of research. "We recognize that many people in the United States are currently suffering with symptoms and they are very frustrated as to whether there is evidence of their disease."
Q: What is Morgellons?
A: It's a mysterious condition primarily marked by skin disorders. The CDC refers to it as an "unexplained dermopathy."
Q: What are its symptoms?
A: Unexplained sores that won't heal; materials protruding from the skin that look like thin, multicolored threads or black sand; chronic fatigue; "brain fog," including difficulty concentrating and short-term memory problems; muscle and joint pain; sensation of something crawling beneath the skin.
Q: What are common diagnoses of Morgellons symptoms?
A: Many doctors do not believe Morgellons exists, and patients are sometimes diagnosed with skin conditions such as scabies or eczema; Lyme disease; or delusional parasitosis, a psychiatric condition.
Q: Is there a treatment?
A: There is no standard treatment.
Q: How many people have Morgellons?
A: The Morgellons Research Foundation reports that 10,000 families in the United States have registered claiming at least one family member has the disease. Of those families, 150 to 500 are in the Bay Area.
E-mail Erin Allday at eallday@sfchronicle.com.
This article appeared on page B - 1 of the San Francisco Chronicle
A New Hobby
Here's the link: http://www.heavens-above.com/
The hobby is satellite observing. You do not need any equipment. The cool thing about the hobby, general observations are done either right before dawn, or right after sunset. And here is NASA's Real-Time satellite trackering link: http://science.nasa.gov/Realtime/jtrack/3d/JTrack3D.html
Enjoy, all you have to do is get out of your house around sunset . The "Heaven's Above" web page publishes exactly where and when to look. It's fun and educational for young people, as well as adults.
By Laura Kinoshita, Special to LiveScience
posted: 08 January 2008 06:27 am ET
An explosive star within our galaxy is showing signs of an impending eruption, at least in a cosmic time frame, and has for quite some time. From 1838 to 1858, the star called Eta Carinae brightened to rival the light of Sirius, the brightest star in the sky, and then faded to a dim star. Since 1940 it has been brightening again, and scientists think Eta Carinae will detonate in 10,000 to 20,000 years.
Fortunately, Eta Carinae is far away, at least 7,500 light-years from Earth. If it explodes, most of its energy will be scattered or absorbed in the vast emptiness of space. It also happens to be tilted about 45 degrees from the line of sight to Earth, so any type of gamma-ray burst, a high-energy outburst expected with this star's eventual eruption, would miss the Earth. Cosmic rays would be diffused by magnetic fields, and most of the damaging light would not affect life on Earth.
In general, threats to life on Earth from supernovae are extremely small, for all except the nearest explosions — those 30 light-years away or closer.
But what if a supernova were 100 times brighter than usual? Would there be any risk to life on Earth then?
But what if a supernova were 100 times brighter than usual? Would there be any risk to life on Earth then?
Astronomers found such a record-breaking supernova last year, SN 2006gy.
Brightest ever
SN 2006gy was the brightest supernova ever recorded until an even brighter one was discovered in November.
Astronomers now know the progenitor of SN 2006gy was remarkably similar to Eta Carinae. They warn a superluminous supernova might explode right in our own galaxy.
Brian Thomas at Washburn University has been studying the effects of astronomical explosions at the Goddard Space Flight Center. He decided to investigate what would happen to Earth's protective ozone layer if Eta Carinae explodes with the brilliance of SN 2006gy.
It turns out that even though SN 2006gy was one of the brightest supernovae ever recorded, it did not generate a large amount of X-rays. Thomas and his team found most of the light, including damaging X-rays and cosmic rays, would scatter into space before ever reaching Earth.
So would there be any damage to Earth from such a spectacular event? Though Thomas found X-rays and cosmic rays would cause little damage, he also looked at optical light, particularly short-wavelength blue light (400 nanometers), where the spectrum of SN 2006gy peaked. No one had ever considered the effects of this light before, either from supernovae or any other type of event.
"The visible light could be significant," Thomas says, "But this depends a little bit on your definition of significant."
Brighter than Venus
If Eta Carina were to explode like SN 2006gy, it would quickly become the brightest object in the sky other than the sun and the moon.
For those living where Eta Carina is always above the horizon (Antarctica, New Zealand and extreme southern regions of Australia and South America) the light would vastly outshine Venus, visible even during the day. The radiation would illuminate the evening sky with a bluish glow nearly strong enough to read by, and the effect would likely last for months — perhaps six or more.
The cumulative effects of long-duration exposure to blue-enhanced light would begin to interfere with life on Earth.
Those who study chronobiology, or the effects of biological timing, have found that low levels of blue light can strongly affect the endocrine systems of mammals by causing physiological and alerting responses. Blue-enhanced light is associated with reduced levels of melatonin production and affects circadian rhythms. For these reasons, it is sometimes prescribed to counteract seasonal affective disorder (SAD) or winter depression.
"This is not going to be an 'everything dies immediately' kind of event," Thomas said. "But with the risk factors associated with higher levels of this kind of light it's certainly something that could be important in the longer run."
New threshold
In a paper about to be published in the journal Astrobiology, Thomas explains that even short exposures to blue light can increase insomnia, reduce resistance to infection and is being studied as a possible risk of cancer.
Yet, in the case of Eta Carinae, the effect of these optical photons would be minimal. The scattering of photons by dust and gas is greatest at blue wavelengths (thus giving Earth its blue sky) and the sheer distance of Eta Carinae diminishes the optical intensity by about 20 percent.
But while damage from optical light is not a factor for Eta Carinae, the effects of this light should be considered to any risk assessment of supernovae. Based on his results, Thomas now estimates the biological threshold for supernovae to be about 100 light-years away. At that distance, life on Earth can expect some sort of supernova radiation about once every 20 million years.
I don't know why, but this song reminds me of Rustymadgal:
