Posted: 12/16/2015
- The most likely spots for life in the Milky Way (“So in the new study ... focused on the regions far from a galaxy’s center. They used computer simulations to model an entire Milky Way–like galaxy and its neighbors, the Andromeda and Triangulum galaxies. They then simulated the distribution of gas, stars, and planetary systems within those whorls of stars. Finally, they allowed these galaxies to evolve over billions of years, while mapping out their evolving habitable zones. “We’re the first to look at how the history of galaxies affects their habitability,” … that potentially habitable planets are more likely to remain so if they form in areas far from dense conglomerations of stars, where more supernova explosions occur. The results indicate that for the Milky Way and other spiral galaxies, the most dangerous regions are in the galactic centers, whereas the more diffuse spiral arms pose fewer hazards and are therefore more hospitable to life. Earth lies near the inner edge of this habitable zone.”)
- Super Spiral Galaxies Amaze Astronomers A new breed of giants raises questions about how the biggest galaxies arise (“But as Ogle's team reports in work submitted to The Astrophysical Journal last month, three percent of the most luminous galaxies they found are actually spirals. "They look like normal spiral galaxies, but until you quantify how far away they are, you don't realize how big and bright they are," Ogle says. "I think that's probably why people didn't notice them before." His sample shows 53 spiral galaxies with luminosities between eight and 14 L*. The largest super spiral, located in the constellation Hercules, possesses a disk of stars 440,000 light-years across, four times the size of the Milky Way's stellar disk.”)
- Speedy DNA nanomachines are on a roll (“Now, scientists in the US have developed a DNA roller that is 1000 times faster than most synthetic DNA-based motors and can also pinpoint single mutations. … Known as a ‘burnt-bridge’ mechanism, the DNA will subsequently look for new RNA to bind to. This simple reaction is what causes the ball to roll, with an average velocity of up to 1.9µm per minute. It’s so effective that the team were able to flip the sample upside-down and the ball still rolls at the same speed – inertia or gravity plays no part. … Although such a roller will move in a self-avoiding and random manner, never crossing its former path, it can also travel in a straight line when two balls are joined together. ‘It’s the first example of doing ballistic or linear motion without an external field [or] force,’ Salaita says. The roller is also capable of detecting single base mutations. ‘We saw that they … have specific velocities and it turns out the speed of the motor depends on the rate of DNA and RNA binding, and the rate of the enzyme destroying the RNA,’ he adds. ‘If you have a single base mutation in the RNA, that leads to a change in the velocity of the motor.’”)
- Super-repellent coating ready in seconds (“In recent years, several strategies have been attempted to prepare omniphobic surfaces that repel both polar and apolar liquids. However, they are complex owing to the challenge of creating surfaces with ultra-low contact angle hysteresis, which is what causes liquids to bead and easily slide off a surface. One method is to covalently attach flexible groups onto smooth surfaces to create a slippery liquid-like layer. But this approach is usually time-consuming and involves complicated synthetic chemistry. Now, Liming Wang and Thomas McCarthy at the University of Massachusetts, US, have devised a way to create such smooth and slippery coatings without complex synthetic chemistry and long reaction times. Their method so simple it involves just one step and takes minutes to achieve at room temperature.”)
- Turning Red Blood Cells into Versatile Drug Carriers A startup aims to treat hard-to-treat diseases with genetically modified blood cells. (“Genetically engineering red blood cells to turn them into drug-delivery vehicles could open the door to a vast number of new therapies. And since mature red cells don’t carry any genetic material, they would also carry fewer safety risks than other gene and cell therapies. That’s the idea behind the technology unveiled today by Rubius, an 18-month-old company founded by Flagship Ventures in Cambridge, Massachusetts. Rubius’s first drug will be for phenylketonuria, or PKU, a devastating genetic disorder that renders people with the disease unable to digest the amino acid phenylalanine, which is found in most high-protein foods.”)
- For Cocaine Addicts, Treatment with Magnets May Stop Craving Can magnetic stimulation of the brain shake drug users out of their habits? (“Now the results of the study, involving 29 cocaine addicts seeking treatment at a Padua clinic, are out. They suggest that the magnetic stimulation treatment significantly reduced both cocaine use and cravings. Stefano says his desire for cocaine diminished dramatically after several sessions under the magnet. … The findings, presented in the European journal Neuropsychopharmacology …. are generating optimism among addiction researchers, because there are no effective drug treatments available for cocaine addicts. There is also a theoretical framework to explain why stimulating the brain with magnets might work, since experiments earlier this year produced similar effects in cocaine-addicted rats. ... Invented in the 1980s, TMS has grown in popularity in recent years and was approved by the U.S. Food and Drug Administration as a treatment for depression in 2008. The exact mechanism by which it works is not fully understood. But addiction appears to establish signaling patterns in the brain that compel people to compulsively seek the drug, and applying TMS could disrupt the pattern, just as noise can interfere with a radio signal.”)
- Healthy or sick? Tiny cell bubbles may hold the answer (“In a new study, published in Current Biology, Rutgers scientists isolated and profiled these sub-micron sized cells, known as extracellular vesicles (EVs) in adult C. elegans and identified 335 genes that provide significant information about the biology of EVs and their relationship to human diseases. ... determined that 10 percent of the 335 identified genes in the roundworm regulate the formation, release, and possible function of the EVs. Understanding how EVs are made, dispersed and communicate with other cells can shed light on the difference between EVs carrying sickness or health. ... For decades scientists believed that the EV material released by some human cells - which can only be seen through high-tech electron microscopes - was nothing more than biological debris. ... But Barr said using C. elegans, which have many genes similar to humans, Rutgers scientists have identified new pathways that could control the production of EVs and the cargo they carry, including the proteins responsible for polycystic kidney disease, the most commonly inherited disease in humans. The polycystic kidney disease gene products are secreted in tiny EVs from both humans and worms and no one knows why these proteins are in the EVs, she said.”)
- Researchers Take a Step Toward Vocal Cord Transplants An achievement in tissue engineering suggests that people with damaged vocal cords could eventually get new ones. (“The researchers implanted the engineered tissue into a larynx that had been taken from a dog and had one of its vocal cords removed. They demonstrated that the lab-made tissue vibrates and sounds like healthy tissue. (Click on the video below to hear the sound the tissue makes when researchers push air through the larynx.) Further tests in mice showed that the tissue elicited a minimal immune response, raising the researchers’ hopes that such implants could eventually work in people.”)
- Study Reveals Potential Treatment for Life-Threatening Viral Infections (“Scientists ... have shown for the first time how a previously unknown process works to promote infection in a number of dangerous viruses, including dengue, West Nile and Ebola.
The new study also points to a potential treatment, an experimental antibiotic that appears to inhibit infection by these deadly viruses, all of which lack vaccines and treatments. ... “Most of these viruses use a specific molecule to enter cells,” … “In the new study, we were able to show how a second molecule plays a major and previously unknown role in that process. We also show an antibiotic called duramycin inhibits the actions of this molecule.”) - A sound idea for treating lung disease (“They electrically stimulated a circuit on top of a piezoelectric lithium niobate chip, triggering 'nano-earthquakes' known surface acoustic waves (SAWs). These waves are like small earthquakes travelling only along the surface of the chip, creating vibrations that consequently turn a stem cell solution into an aerosol. … SAWs operate at sufficiently high frequencies (10–100MHz) to nebulise the cells over a much shorter period compared to conventional nebulisers, eliminating the risk of lysis or denaturisation. Their device also enables the nebulisation of cells at very low power, only 1.5W, meaning it can be battery powered and about the size of a mobile phone.”)
- Spin current on topological insulator detected electrically at room temperature (“Topological insulators are insulators inside the bulk, but are conducting on their surfaces with less resistance than the conventional materials. This is possible due to their uniquely strong interaction between electrons' spin and orbital angular momentum with their time reversal symmetry. The interaction is so strong that the spin angular momentum of the electrons is locked perpendicular to their momentum, and generates a spontaneous spin polarized current on the surfaces of topological insulators by applying an electric field.”)
- Physicists investigate unusual form of quantum mechanics (“However, a few exotic quantum systems cannot be represented by wave functions, and so do not obey the associative property but instead are described by nonassociative algebra. One example of a nonassociative quantum system is a group of magnetic monopoles, which are hypothetical magnetic particles that have only a north or a south pole, not both like ordinary magnets.
One of the intriguing consequences of the nonassociative property in quantum mechanics is a "triple" uncertainty relation. "The usual uncertainty relation limits the precision of simultaneous measurements of position and momentum," ... "The triple one limits the precision of simultaneous measurements of all three components of the momentum vector, provided there are magnetic monopoles.”) - Scientists Find Protein 'Talks' to Wrong Partners in Cystic Fibrosis (“By removing this chatter, researchers partially restored the protein’s normal function. The findings suggest that therapies could one day treat the root cause of cystic fibrosis, not just the symptoms.”)
No comments:
Post a Comment