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Conjunctival FOXP3 Expression in Trachoma
The processes that lead to the disease and its sequelae are not fully understood. Examination of the immune response as the infection unfolds is key to understanding the immunopathogenesis of ocular C. trachomatis infection (OCI). Infectious diseases are often characterised by an incubation period, in which infection is present without clinical disease; a period during which both infection and disease are present; and a period when clinical signs persist after infection has been cleared [7]. Miller et al. [8] have proposed that OCI follows such a pattern based on the clinical and microbiological observation of trachoma. Earlier work by our group supports this proposal [9]. We identified individuals with infection in the absence of clinical disease, and individuals with clinical signs in the absence of infection. Follow-up examination found that individuals who were PCR-positive but clinically negative were more likely to develop clinical signs than PCR-negative individuals. Conversely, clinical signs were twice as likely to have resolved after 1 mo in PCR-negative individuals with disease as in those who were PCR-positive. Dissection of the immune response in individuals at these times should identify key components of the immune response associated with the acquisition or resolution of infection and clinical signs of trachoma........ Posted by: Sean Permalink Source APL-Built Spacecraft Set for Aug 31 Launch
Built and operated for NASA by the Johns Hopkins University Applied Physics Laboratory (APL), in Laurel, Md., the two-year STEREO (Solar TErrestrial RElations Observatory) mission will explore the origin, evolution and interplanetary consequences of coronal mass ejections. These powerful solar eruptions are a major source of the magnetic disruptions on Earth and a key component of space weather, which can greatly affect satellite operations, communications, power systems, and the lives of astronauts in space. "Building and testing two spacecraft simultaneously has been a technical and scheduling challenge, but an effort at which we've been successful," says Ed Reynolds, APL STEREO project manager. "The entire STEREO team is so proud and excited to launch the twin observatories and be part of the first mission to capture coronal mass ejections in 3-D." To capture the sun in 3-D, the twin observatories will fly as mirror images of each other. One of the observatories will be placed ahead of Earth in its orbit around the sun and the other behind. Just as the slight offset between your eyes provides you with depth perception, this placement will allow the STEREO observatories to obtain 3-D images and particle measurements of the sun......... Posted by: Brooke Permalink Source Loss Of Just One Species Makes Big Difference
The flannelmouth characin is native to South American rivers. (Photo by Brad Taylor)
Brad Taylor, currently a research associate in the department of biological sciences at Dartmouth, and his colleagues studied a fish called the flannelmouth characin (Prochilodus mariae) native to South American rivers. This particular fish eats detritus, the fine organic matter on the river bottom, and because of this, it plays a critical role in regulating the breakdown and transport of carbon in the rivers. "This fish species is a popular food source; it is harvested regularly, and in some cases, it's overfished," says Taylor, the lead author on the study that was published in the August 11 issue of the journal Science. "We learned that removing this particular fish greatly altered the metabolic activity of the river ecosystem. Other fish species did not compensate for the lack of Prochilodus, an effect consistent with observations from other rivers where they have been excluded much longer by dams". The researchers used a heavy, plastic divider to split a 210-meter stretch (a little more than a tenth of a mile) of Rio Las Marías in Venezuela into two separate river sections. On one side, they removed only Prochilodus, and on the other, all the fish remained. The team then took a series of measurements upstream and downstream to quantify the transport of particulate organic carbon (POC)......... Posted by: Ashley Permalink Source Ocean Noise Has Increased Considerably
Sean Wiggins (left) and John Hildebrand deploy listening devices at various locations around the world. This instrument was recovered in the Gulf of California.
New research reported in the recent issue of the Journal of the Acoustical Society of America (JASA) has shown a tenfold increase in underwater ocean noise off Southern California's coast as compared with the 1960s. Mark McDonald of WhaleAcoustics in Bellvue, Colo., and John Hildebrand and Sean Wiggins of Scripps Oceanography accessed acoustic data recorded in 1964-1966 through declassified U.S. Navy documents and compared them against acoustic recordings made in 2003-2004 in the same area off San Nicolas Island, one of the Channel Islands more than 160 miles west of San Diego. The results showed that noise levels in 2003-2004 were 10 to 12 decibels higher than in 1964-1966, an average noise increase rate of three decibels per decade. The culprit behind the increase, as per Hildebrand, appears to be a byproduct of the vast increase in the global shipping trade, the number of ships plying the world's oceans and the higher speeds and propulsion power for individual ships. The noise detected off Southern California originates from ships traveling across the entire North Pacific Ocean. As per Lloyd's Register figures quoted in the JASA paper, the world's commercial fleet more than doubled in the past 38 years, from 41,865 in 1965 to 89,899 in 2003......... Posted by: Tyler Permalink Source New Species Of Sea Urchin For Acution At Ebay
Image courtesy of Ebay
Sea Urchins are a member of the Phylum Echinodermata, Class Echinoidea. Rather then having arms or legs the sea urchin actually has long spines as a substitute. These spines are used primarily for camouflage, locomotion, and defensive purposes. The sea urchin feeds on sea grasses, algae, and decaying organic matter. One can see their close relationship to the sand dollar and starfish by looking closely at their underside, near the middle, where the familiar 5 pointed star pattern can be found. Its body is enclosed in a rigid shell, or test, made up of ten double rows of immovable plates firmly joined in a regular pattern. Sea urchins reproduce sexually by discharging either eggs or sperm into the sea, where the eggs are fertilized. This animal, which feeds primarily on vegetation and small organisms, can easily repair damage to its shell, spines, tube feet, and pedicellarieae by regenerating new parts. Sea urchins live on undersea rocks, ledges, boulders, or coral reefs......... Posted by: Ashley Permalink Source Skin Cancer Fear Grows As Ozone Layer Gets Thinner
Levels of ozone, which play a crucial role in helping to filter out harmful ultraviolet rays from the sun, were believed to be rising after the systematic banning of the CFC chemicals which were damaging it. But now experts believe global warming is changing conditions in the upper atmosphere and leading to a reduction in levels again. Cancer experts warned yesterday that the results meant it was more important than ever for people to take precautions when in the sun. ........ Posted by: Sean Permalink Source Publisher Takes Weight Challenge Seriously
Reevs found out he has hypertension and in order to lower it, he became part of the Healthy Weight Journal Challenge. "There is a direct link between obesity and high blood pressure," he said. "To me it seems stupid taking medicine if you can take care of yourself healthwise"......... Posted by: Sean Permalink Source Salads With Some Fat Are Healthier
Far from being a dieter's worst enemy, researchers are discovering that a little fat can actually do a lot of good. The researchers aren't saying fry your salad in bacon grease! But they say don't cut all fat out of your diet either. Why? It takes some fat to help your body absorb the cancer fighting nutrients in your vegetables. Jennifer Jarvis has always tried to stick to a light, healthy diet. But when she volunteered for a food study recently, she learned something that was a little hard to swallow -- that cutting fat completely out of her diet, was actually robbing her body of nutrients......... Posted by: Sean Permalink Source How Acid Reflux Leads To Esophageal Cancer
The study found that the enzyme NOX5-S is affected by exposure to acid and that it produces stress on cells, activating genes that lead to DNA damage. For the first time, researchers have outlined the signaling pathway from cells damaged by acid, to the progression of esophageal cancer. They believe the same process may happen in the body when cells are exposed to acid reflux. "The role of acid is controversial. But we show that by exposing cells to acid for short periods of time, that affects a particular enzyme, triggering a chain of events that possibly leads to cancer of the esophagus. Now that we have a better understanding of the signaling pathway, we can possibly identify who is at risk of developing cancer by determining the levels of this enzyme," says senior author Weibiao Cao, a researcher at Rhode Island Hospital and an assistant professor of medicine and surgery at Brown Medical School. The study looked at human cancer cells and biopsies from patients with Barrett's esophagus (BE), a condition where cells in the esophagus have been altered by gastroesophageal reflux disease (GERD), or acid reflux. Acid reflux is believed to be a major risk factor for cancer in people with Barrett's esophagus......... Posted by: Sean Permalink Source How Light Pushes Atoms
Einstein proposed that a light wave is made of photons that carry discrete packets of energy. "When a photon hits an atom, the atom recoils with a speed that is determined by the photon's momentum, similar to two balls colliding on a billiard table," Gibble explains. Physicists often think of a focused laser beam as the intense intersection of two or more infinitely wide light waves, and Gibble's discovery provides an important new understanding of what happens to an atom that is pummeled by photons coming from the different directions of these multiple intersecting light waves. "You might believe that an atom would absorb a photon randomly from only one of the beams, but this paper shows that the atom feels the effect of the photons from all of the beams simultaneously and, surprisingly, that it recoils with a speed that is less than it would get from the momentum of any one of the infinitely wide photons"......... Posted by: Kevin Permalink Source |
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