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Sometimes, the key to understanding is to take a good, hard look. Scientists have been doing just that, training their eyes on the telomerase enzyme which is known to play a significant role in aging, cancer and other diseases. For the first time, researchers have mapped out the structure of the entire enzyme complex. The researchers from UCLA and UC Berkeley say this breakthrough could lead to new ways of combatting disease, particularly cancer.
It has long been known that there are two radiation belts — the inner and outer belts — surrounding our planet. Recently, however, NASA’s Van Allen Probes mission brought to light a third radiation belt, an important discovery that goes to show that even the supposedly best-understood theories may need amending.
The Standard Model of physics is currently associated with four fundamental forces: gravity, electromagnetism and the strong and weak nuclear forces. But some particle physicists have proposed a fifth force that would extend the Standard Model, which describes matter and the way it interacts by breaking down matter into a number of particles. In a study published in the Feb. 22 issue of the journal Science, Larry Hunter of Amherst College and his colleagues at Amherst and the University of Texas at Austin have narrowed down the search for what scientists call “long-range spin-spin interactions” that would be tied to such a fifth force. This force would involve electrons, protons and neutrons interacting over long distances.
Even after stars cease to shine, their light continues to make its way throughout the universe. Astronomers have been able to make the most accurate measurement of extragalactic background light (EBL), the aggregate starlight in the cosmos, to date. They used data from NASA’s Fermi Gamma-ray Space Telescope, whose primary mission was to measure the EBL of our universe.
With the help of NASA’s Hubble and Spitzer Space Telescopes, a team of astronomers led by Hopkins’ Wei Zheng has discovered the most distant – and, hence, the youngest – galaxy ever observed with high confidence.
The Wilkinson Microwave Anisotropy Probe (WMAP) team, led by Charles L. Bennett, a professor in Hopkins’s Physics and Astronomy Department, was recently awarded the 2012 Gruber Cosmology Prize. The award was presented in recognition of their contributions to the Standard Cosmological Model, which helped transform the field of cosmology from “appealing scenario into precise science.”
In order to glean information about Earth’s climate history, scientists can analyze ice cores from Greenland and Antarctica’s ice caps. Similarly, Mars’ past climate can be determined by examining its ice caps. Using this technique, researchers from the Niels Bohr Institute at the University of Copenhagen have put together the first dated account of climate history for Mars. Their findings show that the variations in Mars’ climate are linked to solar insolation, which is a measure of solar radiation energy.
A new technique involving nanoparticles has exciting potential benefits for brain cancer patients. According to a recent study by scientists at the Stanford University School of Medicine, the tiny particles can be imaged in three ways to facilitate and guide the removal of brain tumors from mice. Led by Sam Gambhir of the Radiology Department, the team of scientists engineered nanoparticles that detected and highlighted brain tumors. By offering a precise way of determining the boundaries of the tumor, the method can be used to remove brain tumors with unprecedented accuracy. The most serious kind of brain tumor is glioblastoma, of which 3,000 cases are diagnosed annually. Without treatment, patients with glioblastoma are expected to die within three months. Whenever possible, such tumors are removed, but this procedure only prolongs the patient's life by about one year, since even the best neurosurgeons find it almost impossible to remove the whole tumor without sacrificing healthy brain. This lack of precision is an especially large problem when one considers the shape of these tumors, which are typically rough, with tiny fingerlike protrusions that follow blood vessels and nerves. In addition, the primary tumor can, while replicating and migrating cells, produce tiny tumor patches called micrometastases, which are nearly invisible to the surgeon's eye and can infiltrate otherwise healthy tissue. The micrometastases can then grow into new tumors. This study used what were essentially imaging reagents coated on minuscule gold balls, each measuring less than five one-millionths of an inch in diameter. The scientists hoped that injecting these nanoparticles intravenously would cause them to seek out tumors but leave healthy brain tissue alone. Since the blood vessels that feed brain tumors are quite permeable, the particles would escape from the vessels and attach themselves to the tumor. Thanks to the gold cores of the particles, they would then be visible to each of three imaging techniques. The first kind is magnetic resonance imaging (MRI), which surgeons already commonly use to gauge where the tumor is likely to be before they operate. The nanoparticles are coated with an MRI contrast agent, gadolinium. However, while MRI can determine a tumor's boundaries, it is used preoperatively and therefore cannot perfectly describe the tumor at the time of operation, given the dynamic nature of both the tumor and the brain. The second kind of imaging used is called photoacoustic imaging. The nanoparticles' gold cores absorb pulses of light and produce ultrasound signals that allow for the creation of a three-dimensional image of the tumor. The third, Raman imaging, uses materials in the coating of the particles to give off small amounts of light produced in a specific pattern of wavelengths. The weak signals are amplified by the gold cores, and can then be captured by a special microscope. The scientists began by showing that the nanoparticles targeted only tumor tissue and not healthy tissue. They then implanted different types of human glioblastoma cells into the brains of mice. Injecting the nanoparticles into the tail veins of the mice, the scientists were able to use all three imaging methods to visualize the tumor. The MRI scans and photoacoustic images were able to produce accurate images of the tumor pre-operation and during the operation, respectively. The bulk of the animal's tumor was initially cleared using these first two methods. However, to produce sufficiently precise detail, the sensitive Raman images proved to be critical. Because Raman signals were only produced by nanoparticles, after the clearing of most of the tumor, this third technique was used to flag and then remove any residual micrometastases and fingerlike projections in adjacent normal tissue. This technique offers hope for the field of brain cancer treatment, allowing for the precisely controlled removal of both the tumor and residual tumor material. According to Gambhir, the technique might even someday be used to treat other types of tumors.
Have you ever had a single scent, melody or picture transport you to a distant memory? MIT scientists have done something similar but with neurons as the trigger. In other words, they have been investigating whether a few neurons can bring to mind an entire memory.
Bootup Baltimore is a unique community service group on campus that intersects technology with charity. If you're interested in technology - even if you don't have much computer knowledge - and in reaching out to the Baltimore community, you may be interested in Bootup Baltimore. The News-Letter sat down with Bootup Baltimore's Secretary and Publicity Manager, Daniel Levenson, who talked to us about how the group works. In a nutshell, Bootup Baltimore is a computer community service organization that provides substantive technology-related aid to those in need in the form of computers and the teaching of computer skills. It has two main divisions. The first is refurbishment; computers are donated to the group, which either breaks them down for parts or refurbishes them to make them ready for re-donation to other charitable organizations, churches and schools. Many of these schools are ones that the group coordinates with to conduct teaching sessions, which comprise the second main operation of Bootup Baltimore. Elementary school students are trained in computer skills, such as word processing, image editing, basic programming, hardware maintenance and web development. As Levenson puts it, these are "very applicable skills that students in public schools aren't necessarily taught," adding, "It's a really interesting program, really fun."Levenson emphasizes that computer knowledge is not necessary for active participation in the group: "If you think you're very computer-unsavvy, it's totally not an issue." While the group seeks members of all skill levels, he points out that "you just need to have an interest. We've definitely had people come who haven't had computer experience, and they've loved it." The group trains and briefs its teachers on what is to be taught, and there is a refurbishment coordinator who is always at refurbishing sessions to show everyone how the process works. "It's pretty algorithmic to a certain level, so it's definitely not too challenging, but it's pretty cool," says Levenson. But, as he points out, "it's a great opportunity to crack open computers - we've got tons." For teachers, this opportunity to help and nurture computer skills in elementary school students is a very engaging one. As Levenson points out, "It's not like you're at the outskirts of the process by helping teaching. You're really teaching." Thus, while it is easy to get involved in Bootup Baltimore's programs, the impact of the group's activities is formidable.Levenson also stresses the importance of what Bootup Baltimore does: "There's definitely very much a need for our services. There will always be more public school students that could use our aid, absolutely. There are tons of organizations that are reaching out to us." And, as extra incentive for elementary schools to participate, Bootup Baltimore has also been known to give them computers at the end of the program. Moreover, members of Bootup Baltimore become part of a powerful and personal process. According to its mission statement, the organization aims to "both expand computer access in Baltimore and create opportunities for [their] participants to engage with technology in a personal way." The skills that Bootup Baltimore fosters, which are crucial in the modern world, are also provided in tandem with Bootup Baltimore's goal of promoting sustainability, as well as other valuable services. If you are interested in being a part of Bootup Baltimore's efforts, check them out at bootupbaltimore.org, where you can join their mailing list and get in touch with their officers.
According to a new study, asteroids could be falling into the supermassive black hole in the middle of our Milky Way. The study is significant because the findings suggest that a huge number of asteroids must be present around the black hole. NASA's Chandra spacecraft has been detecting X-ray flares coming from Sagittarius A* (or Sgr A* for short) about once a day for several years. According to the study, the flares may be caused by the black hole swallowing up asteroids in its proximity.Sgr A* is the black hole in the center of our galaxy, and due to the clearly hostile environment around a black hole, it has been doubted that asteroids could form nearby at all. However, the study, led by Kastytis Zubovas of the University of Leicester in the United Kingdom and published in the Monthly Notices of the Royal Astronomical Society, suggests that, in fact, large numbers of asteroids may be present around Sgr A*, as evidenced by the production of the flares. In fact, it is likely that a cloud near Sgr A* could contain trillions of asteroids, as well as comets that were stripped from their parent stars by the black hole. The distance between the Earth and the sun is roughly 100 million miles or 160 million kilometers. At this distance from Sgr A*, asteroids would get torn to pieces by the black hole's gravity. In addition, if an asteroid gets too close to a star or planet close to Sgr A*, its orbit could change, meaning that it could be thrown toward the black hole. Then, as the asteroids come into contact with the hot gas flowing onto Sgr A*, the asteroid fragments would be vaporized by friction, just as meteors get burned up by gases in the Earth's atmosphere. It is this vaporization that probably gives rise to the X-ray flares detected by Chandra. The flares last for a few hours and can range from a few times to nearly 100 times as bright as the black hole usually is. Then, whatever is left of the asteroid gets swallowed up by the black hole. The flares seen around Sgr A* would have to be generated by asteroids at least six miles or 10 km, wide. Although the black hole is probably also munching up smaller asteroids, the flares that would appear as a result would be too faint to detect. Previous modeling work has estimated that trillions of asteroids are likely to be found around Sgr A*. Findings from this study roughly agree with this conclusion. While a few trillion asteroids should have been swallowed up by the black hole over the 10-billion-year lifetime of the Milky Way, the majority of the total number of asteroids should remain untouched. The results could also be an indication of planets that come too close to the black hole, rather than asteroids, which would result in even brighter flares. However, such events would be extremely rare, since asteroids are much more common than planets. Nevertheless, it is likely that it has happened in the past: about 100 years ago, the X-ray flares of Sgr A* became brighter by a factor of a million. Unfortunately, this happened before telescopes were invented. It has been detected, however, by X-ray 'echoes' reflecting off clouds, according to the researchers. The study provides exciting new evidence for the size, amount and proximity of asteroids around our galaxy's black hole, contrary to doubts regarding the existence of asteroids around Sgr A*.
What makes a tree a ‘miracle tree'? The plant known as Moringa oleifera, or drumstick tree (due to the shape of its seedpods), has been dubbed miraculous by some who are optimistic about its ability to increase the availability of clean water to areas susceptible to drought and contamination. This thin-branched tree has seeds that attract and destroy bacteria in water. These intriguing properties have led several teams of researchers to investigate the Moringa tree's applications to cleaning water.
NASA's Hubble Space telescope was recently able to make an extraordinary discovery by looking nine billion years into the past. This discovery, made possible by Hubble's near-infrared capabilities, involves a group of dwarf galaxies that, while young and small, are producing stars at an incredibly rapid rate. The number of stars they contain is likely to double in 10 million years.
It is well known that Neanderthals had legs that were lower and significantly shorter than those of the typical modern humans. However, most studies in the past concluded that this was due to the cold climate they lived in, as shorter legs reduce the surface area through which heat could escape. Yet new research at Hopkins recently revealed an alternative account: that their shorter lower legs might have been advantageous to Neanderthals, aiding them in moving over mountainous terrain.
While invisibility cloaks are still mostly associated with fantasy (and Harry Potter), physicists and engineers have already developed rudimentary invisibility cloaks that shield objects from light, sound, and water waves. Now, they have moved cloaking technology another step forward with the development of a cloak that can shield an object from a static magnetic field, keeping the field undisturbed – an anti-magnet cloak.
Researchers at the University of Bristol have analyzed some of Earth's oldest rock samples and found that our planet's accessible precious metals were added to it by chance. If not for a cataclysmic meteorite shower that struck the earth over 200 million years after its formation, we would not be able to access today much of the precious metals that make up many of our thriving industries.
A new exhibit at the Walters Art Museum features art from Lonni Sue Johnson, who lost her memory after contracting a viral infection that resulted in heavy brain damage. Her "recovery art" has helped scientists learn more about the effects of amnesia, as well as the role of language and memory in creativity.
NASA scientists have found a class of star-like bodies that are the coldest discovered to date. Their temperatures, which have been detected using the Wide-field Infrared Survey Explorer (WISE), can be even cooler than the human body.
Three studies conducted by researchers at the University of California at Berkeley, Columbia University, and the Mount Sinai School of Medicine have recently shown that children who were exposed before birth to substantial levels of neurotoxic pesticides tend to have somewhat lower IQs by the time they start school, compared to children with virtually no exposure. These differences in IQ could translate into a hampering of these children’s ability to learn and, later on, to be as competitive as their peers in the workplace.
After searching for dark matter for 100 days, the XENON100 tank failed to find any evidence of the material. While the negative result does not mean that dark matter does not exist, it does indicate that it is more elusive than scientists had previously imagined.