New Computerized System Estimates Geographic Location Of Photos

Researchers at Carnegie Mellon University have devised the first computerized method that can analyze a single photograph and determine where in the world the image likely was taken. It's a feat made possible by searching through millions of GPS-tagged images in the Flickr online photo collection.The IM2GPS algorithm developed by computer science graduate student James Hays and Alexei A. Efros, assistant professor of computer science and robotics, doesn't attempt to scan a photo for location clues, such as types of clothing, the language on street signs, or specific types of vegetation, as a person might do. Rather, it analyzes the composition of the photo, notes how textures and colors are distributed and records the number and orientation of lines in the photo. It then searches Flickr for photos that are similar in appearance. -Science Daily

Life's Raw Materials May Have Come From The Stars, Scientists Confirm

Scientists have confirmed for the first time that an important component of early genetic material which has been found in meteorite fragments is extraterrestrial in origin, in a paper published on 15 June 2008.The finding suggests that parts of the raw materials to make the first molecules of DNA and RNA may have come from the stars.The scientists, from Europe and the USA, say that their research provides evidence that life’s raw materials came from sources beyond the Earth.The materials they have found include the molecules uracil and xanthine, which are precursors to the molecules that make up DNA and RNA, and are known as nucleobases.The team discovered the molecules in rock fragments of the Murchison meteorite, which crashed in Australia in 1969.They tested the meteorite material to determine whether the molecules came from the solar system or were a result of contamination when the meteorite landed on Earth.The analysis shows that the nucleobases contain a heavy form of carbon which could only have been formed in space. Materials formed on Earth consist of a lighter variety of carbon.“We believe early life may have adopted nucleobases from meteoritic fragments for use in genetic coding which enabled them to pass on their successful features to subsequent generations.”Between 3.8 to 4.5 billion years ago large numbers of rocks similar to the Murchison meteorite rained down on Earth at the time when primitive life was forming. The heavy bombardment would have dropped large amounts of meteorite material to the surface on planets like Earth and Mars.“Because meteorites represent left over materials from the formation of the solar system, the key components for life -- including nucleobases -- could be widespread in the cosmos. As more and more of life’s raw materials are discovered in objects from space, the possibility of life springing forth wherever the right chemistry is present becomes more likely.” science daily-

Sea's Ebb And Flow Drive World's Big Extinction Events

If you are curious about Earth's periodic mass extinction events such as the sudden demise of the dinosaurs 65 million years ago, you might consider crashing asteroids and sky-darkening super volcanoes as culprits. But a new study, published online June 15, 2008 in the journal Nature, suggests that it is the ocean, and in particular the epic ebbs and flows of sea level and sediment over the course of geologic time, that is the primary cause of the world's periodic mass extinctions during the past 500^[sc1] million years."The expansions and contractions of those environments have pretty profound effects on life on Earth," says Shanan Peters, a University of Wisconsin-Madison assistant professor of geology and geophysics and the author of the new Nature report.In short, according to Peters, changes in ocean environments related to sea level exert a driving influence on rates of extinction, which animals and plants survive or vanish, and generally determine the composition of life in the oceans.Since the advent of life on Earth 3.5 billion years ago, scientists think there may have been as many as 23 mass extinction events, many involving simple forms of life such as single-celled microorganisms. During the past 540 million years, there have been five well-documented mass extinctions, primarily of marine plants and animals, with as many as 75-95 percent of species lost."The major mass extinctions tend to be treated in isolation (by scientists)," Peters says. "This work links them and smaller events in terms of a forcing mechanism, and it also tells us something about who survives and who doesn't across these boundaries. These results argue for a substantial fraction of change in extinction rates being controlled by just one environmental parameter." Sciencedaily-

Synthetic Cocoa Chemical Slows Growth Of Tumors

A synthetic chemical based on a compound found in cocoa beans slowed growth and accelerated destruction of human tumors in laboratory studies, and should be tested further for cancer chemoprevention or even treatment, say researchers at Georgetown University Medical Center.We have all heard that eating chocolate is good for you; this study suggests one reason why that might be true," says the study's lead author Min Kim, Ph.D., a research scientist in the Department of Oncology at Lombardi Comprehensive Cancer Center.Published online today in Cell Cycle, the researchers describe how four different human tumor cells lines out of 16 tested were sensitive to the chemical, known as GECGC. The strongest response was seen in two different colon cancers; growth was cut in half and most of the tumor cells were damaged.Normal cells were not affected by GECGC, which makes the chemical a candidate for cancer chemoprevention, says Kim ScienceDaily-

Even The Antarctic Winter Cannot Protect Wilkins Ice Shelf

Wilkins Ice Shelf has experienced further break-up with an area of about 160 km² breaking off from 30 May to 31 May 2008. ESA’s Envisat satellite captured the event – the first ever-documented episode to occur in winter.Wilkins Ice Shelf, a broad plate of floating ice south of South America on the Antarctic Peninsula, is connected to two islands, Charcot and Latady. In February 2008, an area of about 400 km² broke off from the ice shelf, narrowing the connection down to a 6 km strip; this latest event in May has further reduced the strip to just 2.7 km.New images highlight the rapidly dwindling strip of ice that is protecting thousands of kilometres of the ice shelf from further break-up."The remaining plate has an arched fracture at its narrowest position, making it very likely that the connection will break completely in the coming days," Braun and Humbert said. Long-term satellite monitoring over Antarctica is important because it provides authoritative evidence of trends and allows scientists to make predictions. Ice shelves on the Antarctic Peninsula are important indicators for on-going climate change because they are sandwiched by extraordinarily raising surface air temperatures and a warming ocean.The Antarctic Peninsula has experienced extraordinary warming in the past 50 years of 2.5°C, Braun and Humbert explained. In the past 20 years, seven ice shelves along the peninsula have retreated or disintegrated, including the most spectacular break-up of the Larsen B Ice Shelf in 2002, which Envisat captured within days of its launch.

How The Brain Separates Audio Signals From Noise

How are we able to follow a single conversation in the midst of a crowded and noisy room? Little is known about how the human brain accomplishes the seemingly simple task of extracting meaningful signals from noisy acoustic environments.n a new article, Alexander Gutschalk and his colleagues provide an important advance towards solving this mystery by discovering the neural correlates of conscious auditory perception.The researchers use magnetoencephalography (MEG) to record brain activity as human subjects detect target tones in a complex auditory scene consisting of distracting tones. They discover that the awareness of these sounds correlates with activity in high-level auditory regions in the brain, but not the initial cortical region where sound is processed.Because many previous neuroimaging studies have used simple stimuli in unnatural contexts, such as pure tones in an otherwise quiet environment, this novel study will influence future research investigations aimed at uncovering the neural mechanisms of conscious perception in natural and complex environments.

Nanoparticles Aid Bone Growth

In the first study of its kind, bioengineers and bioscientists at Rice University and Radboud University in Nijmegen, Netherlands, have shown they can grow denser bone tissue by sprinkling stick-like nanoparticles throughout the porous material used to pattern the bone.he research is available online and slated to appear in the journal Bone. It's the latest breakthrough from the burgeoning field of tissue engineering. The new discipline combines the latest research in materials science and biomedical engineering to produce tissues that can be transplanted without risk of rejection. To grow new bone, tissue engineers typically place bone cells on porous, biodegradable materials called scaffolds, which act as patterns. With the right chemical and physical cues, the cells can be coaxed into producing new bone. As the scaffold degrades, it is replaced by new bone.In the experiments, the researchers implanted two kinds of scaffolds into rabbits. One type was made of a biodegradable plastic called poly(propylene fumarate), or PPF, which has performed well in previous experiments. The second was made of 99.5 percent PPF and 0.5 percent single-walled carbon nanotubes. Nanotubes are about 80,000th the width of a hair. While they are normally about a thousand times longer than they are wide, the researchers used shorter segments that have fared well in prior cytocompatibility studies. Half the samples were examined four weeks after implantation and half after 12 weeks. While there was no notable difference in performance at four weeks, the nanotube composites exhibited up to threefold greater bone ingrowth after 12 weeks than the PPF. Furthermore, the researchers found the 12-week composite scaffolds contained about two-thirds as much bone tissue as the nearby native bone tissue, while the PPF contained only about one-fifth as much.

Mikos said the nanocomposites performed better than anticipated. In fact, the results indicate that they may go beyond passive guides and take an active role in promoting bone growth. ScienceDaily-