Replica Watches

2013-08-01

NASA's Cassini sees forces controlling Enceladus jets

July 31, 2013 — The intensity of the jets of water ice and organic particles that shoot out from Saturn's moon Enceladus depends on the moon's proximity to the ringed planet, according to data obtained by NASA's Cassini spacecraft.

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The finding adds to evidence that a liquid water reservoir or ocean lurks under the icy surface of the moon. This is the first clear observation the bright plume emanating from Enceladus' south pole varies predictably. The findings are detailed in a scientific paper in this week's edition of Nature.

"The jets of Enceladus apparently work like adjustable garden hose nozzles," said Matt Hedman, the paper's lead author and a Cassini team scientist based at Cornell University in Ithaca, N.Y. "The nozzles are almost closed when Enceladus is closer to Saturn and are most open when the moon is farthest away. We think this has to do with how Saturn squeezes and releases the moon with its gravity."

Cassini, which has been orbiting Saturn since 2004, discovered the jets that form the plume in 2005. The water ice and organic particles spray out from several narrow fissures nicknamed "tiger stripes."

"The way the jets react so responsively to changing stresses on Enceladus suggests they have their origins in a large body of liquid water," said Christophe Sotin, a co-author and Cassini team member at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Liquid water was key to the development of life on Earth, so these discoveries whet the appetite to know whether life exists everywhere water is present."

For years scientists hypothesized the intensity of the jets likely varied over time, but no one had been able to show they changed in a recognizable pattern. Hedman and colleagues were able to see the changes by examining infrared data of the plume as a whole, obtained by Cassini's visual and infrared mapping spectrometer (VIMS), and looking at data gathered over a long period of time.

The VIMS instrument, which enables the analysis of a wide range of data including the hydrocarbon composition of the surface of another Saturnian moon, Titan, and the seismological signs of Saturn's vibrations in its rings, collected more than 200 images of the Enceladus plume from 2005 to 2012.

These data show the plume was dimmest when the moon was at the closest point in its orbit to Saturn. The plume gradually brightened until Enceladus was at the most distant point, where it was three to four times brighter than the dimmest detection. This is comparable to moving from a dim hallway into a brightly lit office.

Adding the brightness data to previous models of how Saturn squeezes Enceladus, the scientists deduced the stronger gravitational squeeze near the planet reduces the opening of the tiger stripes and the amount of material spraying out. They think the relaxing of Saturn's gravity farther away from planet allows the tiger stripes to be more open and for the spray to escape in larger quantities.

"Cassini's time at Saturn has shown us how active and kaleidoscopic this planet, its rings and its moons are," said Linda Spilker, Cassini project scientist at JPL. "We've come a long way from the placid-looking Saturn that Galileo first spied through his telescope. We hope to learn more about the forces at work here as a microcosm for how our solar system formed."

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA's Science Mission Directorate in Washington. The VIMS team is based at the University of Arizona in Tucson.

For more information about the Cassini mission, visit: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov .

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New protein discovered with vast potential for treatment of cancer and other diseases

The identification of CPTP was the result of an international collaboration that built on prior research by co-lead author Charles Chalfant, Ph.D., Endowed Chair of Cancer Cell Signaling and member of the Cancer Cell Signaling program at Virginia Commonwealth University Massey Cancer Center as well as professor in the Department of Biochemistry and Molecular Biology at VCU School of Medicine. The team discovered that CPTP regulates levels of biologically active lipids, which are molecules such as fatty acids that often play a role in cell signaling. As its name implies, this study determined that CPTP's main function is to transport ceramide-1-phosphate (C1P), a lipid that helps regulate cell growth, survival, migration and inflammation. Specifically, C1P increases the production of pro-inflammatory eicosanoids -- powerful signaling molecules that contribute to chronic inflammation in diseases such as cancer, asthma, atherosclerosis and thrombosis -- and the discovery of CPTP shines a light on the cellular mechanisms that contribute to these diseases.

"We may have identified the newest target for treating cancer," says Chalfant. "Because of the important role this protein plays in a number of cellular functions, it could also have large implications for a variety of diseases like cancer that are caused by inflammation."

With assistance from Massey's Lipidomics Developing Shared Resource core, the researchers were able to determine the composition of the bioactive lipids regulated by CPTP. Residing in the cytosol, or the liquid within cells, the team found that CPTP regulates catabolism of C1P, a process that breaks down the molecule in order to release its energy. They also demonstrated that CPTP transports C1P to the cellular membrane where it helps synthesize eicosanoids from fatty acids in the membrane.

Confirming a decade of research from Chalfant's laboratory, the scientists provided further proof that C1P regulates group IVA phospholipase A2, an enzyme that promotes inflammation through the production of a fatty acid known as arachidonic acid. The release of arachidonic acid via C1P activation of this enzyme was shown to trigger the production of eicosanoids. These findings help to explain the reported link between ceramide kinase, the enzyme responsible for C1P production, and poor prognosis in breast cancer patients, which further suggests that alleviation of systemic inflammation may lead to better prognosis and better treatment responses.

"Moving forward, we hope to use our knowledge of the structure of CPTP in order to find small molecules and other means that can block it," says Chalfant. "The immediate uses of such therapeutics might be to restore clotting in trauma patients by maintaining the levels of specific eicosanoids that mediate blood clotting. However, with further research we hope to define exactly how CPTP is produced so that we can regulate its production and potentially develop new treatments for a variety of diseases."

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Researchers successfully spoof an 80 million yacht at sea

July 31, 2013 — This summer, a radio navigation research team from The University of Texas at Austin set out to discover whether they could subtly coerce a 213-foot yacht off its course, using a custom-made GPS device.

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Led by assistant professor Todd Humphreys of the Department of Aerospace Engineering and Engineering Mechanics at the Cockrell School of Engineering, the team was able to successfully spoof an $80 million private yacht using the world's first openly acknowledged GPS spoofing device. Spoofing is a technique that creates false civil GPS signals to gain control of a vessel's GPS receivers. The purpose of the experiment was to measure the difficulty of carrying out a spoofing attack at sea and to determine how easily sensors in the ship's command room could identify the threat.

The researchers hope their demonstration will shed light on the perils of navigation attacks, serving as evidence that spoofing is a serious threat to marine vessels and other forms of transportation. Last year, Humphreys and a group of students led the first public capture of a GPS-guided unmanned aerial vehicle (UAV), or drone, using a GPS device created by Humphreys and his students.

"With 90 percent of the world's freight moving across the seas and a great deal of the world's human transportation going across the skies, we have to gain a better understanding of the broader implications of GPS spoofing," Humphreys said. "I didn't know, until we performed this experiment, just how possible it is to spoof a marine vessel and how difficult it is to detect this attack."

In June, the team was invited aboard the yacht, called the White Rose of Drachs, while it traveled from Monaco to Rhodes, Greece, on the Mediterranean Sea. The experiment took place about 30 miles off the coast of Italy as the yacht sailed in international waters.

From the White Rose's upper deck, graduate students Jahshan Bhatti and Ken Pesyna broadcasted a faint ensemble of civil GPS signals from their spoofing device -- a blue box about the size of a briefcase -- toward the ship's two GPS antennas. The team's counterfeit signals slowly overpowered the authentic GPS signals until they ultimately obtained control of the ship's navigation system.

Unlike GPS signal blocking or jamming, spoofing triggers no alarms on the ship's navigation equipment. To the ship's GPS devices, the team's false signals were indistinguishable from authentic signals, allowing the spoofing attack to happen covertly.

Once control of the ship's navigation system was gained, the team's strategy was to coerce the ship onto a new course using subtle maneuvers that positioned the yacht a few degrees off its original course. Once a location discrepancy was reported by the ship's navigation system, the crew initiated a course correction. In reality, each course correction was setting the ship slightly off its course line. Inside the yacht's command room, an electronic chart showed its progress along a fixed line, but in its wake there was a pronounced curve showing that the ship had turned.

"The ship actually turned and we could all feel it, but the chart display and the crew saw only a straight line," Humphreys said.

After several such maneuvers, the yacht had been tricked onto a parallel track hundreds of meters from its intended one -- the team had successfully spoofed the ship.

The experiment helps illustrate the wide gap between the capabilities of spoofing devices and what the transportation industry's technology can detect, Humphreys said.

Chandra Bhat, director of the Center for Transportation Research at The University of Texas at Austin, believes that the experiment highlights the vulnerability of the transportation sector to such attacks.

"The surprising ease with which Todd and his team were able to control a (multimillion) dollar yacht is evidence that we must invest much more in securing our transportation systems against potential spoofing," Bhat said.

It's important for the public and policymakers to understand that spoofing poses a threat that has far-reaching implications for transportation, Humphreys said.

"This experiment is applicable to other semi-autonomous vehicles, such as aircraft, which are now operated, in part, by autopilot systems," Humphreys said. "We've got to put on our thinking caps and see what we can do to solve this threat quickly."

As part of an ongoing research project, funding and travel expenses for this experiment was supported by UT Austin's Wireless Networking and Communications Group through the WNCG's Industrial Affiliates program.

Watch an animation of the spoofing attack, titled "Spoofing on the High Seas": http://youtu.be/ctw9ECgJ8L0

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Guided growth of nanowires leads to self-integrated circuits

Much effort has gone into facilitating the self-assembly of semiconductors, the basic building blocks of electronics, but until recently, success has been limited. Scientists had developed methods for growing semiconductor nanowires vertically on a surface, but the resultant structures were short and disorganized. After growing, such nanowires need to be "harvested" and aligned horizontally; since such placement is random, scientists need to determine their location and only then integrate them into electric circuits.

A team led by Prof. Ernesto Joselevich of the Weizmann Institute's Materials and Interfaces Department has managed to overcome these limitations. For the first time, the scientists have created self-integrating nanowires whose position, length and direction can be fully controlled.

The achievement, reported this week in the Proceedings of the National Academy of Sciences, was based on a method developed by Joselevich two years ago for growing nanowires horizontally in an orderly manner. In the present study -- conducted by Joselevich with Dr. Mark Schvartzman and David Tsivion of his lab, and Olga Raslin and Dr. Diana Mahalu of the Physics of Condensed Matter Department -- the scientists went further, creating self-integrated electronic circuits from the nanowires.

First, the scientists prepared a surface with tiny, atom-sized grooves and then added to the middle of the grooves catalyst particles that served as nuclei for the growth of nanowires. This setup defined the position, length and direction of the nanowires. They then succeeded in creating a transistor from each nanowire on the surface, producing hundreds of such transistors simultaneously. The nanowires were also used to create a more complex electronic component -- a functioning logic circuit called an Address Decoder, an essential constituent of computers.

"Our method makes it possible, for the first time, to determine the arrangement of the nanowires in advance to suit the desired electronic circuit," Joselevich explains. The ability to efficiently produce circuits from self-integrating semiconductors opens the door to a variety of technological applications, including the development of improved LED devices, lasers and solar cells.

Prof. Ernesto Joselevich's research is supported by the Carolito Stiftung and the European Research Council.

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Digest this: Cure for cancer may live in our intestines

July 31, 2013 — Treating a cancerous tumor is like watering a houseplant with a fire hose -- too much water kills the plant, just as too much chemotherapy and radiation kills the patient before it kills the tumor.

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However, if the patient's gastrointestinal tract remains healthy and functioning, the patient's chances of survival increase exponentially, said Jian-Guo Geng, associate professor at the University of Michigan School of Dentistry. Recently, Geng's lab discovered a biological mechanism that preserves the gastrointestinal tracts in mice who were delivered lethal doses of chemotherapy.

The findings, which will appear in the journal Nature, could revolutionize cancer therapy, Geng said.

"It's our belief that this could eventually cure later-staged metastasized cancer. People will not die from cancer, if our prediction is true," said Geng, who emphasized that the findings had not yet been proven in humans. "All tumors from different tissues and organs can be killed by high doses of chemotherapy and radiation, but the current challenge for treating the later-staged metastasized cancer is that you actually kill the patient before you kill the tumor.

"Now you have a way to make a patient tolerate to lethal doses of chemotherapy and radiotherapy. In this way, the later-staged, metastasized cancer can be eradicated by increased doses of chemotherapy and radiation."

Geng's lab found that when certain proteins bind with a specific molecule on intestinal stem cells, it revs intestinal stem cells into overdrive for intestinal regeneration and repair. Stem cells naturally heal damaged organs and tissues, but so-called "normal" amounts of stem cells in the intestine simply cannot keep up with the wreckage left behind by the lethal doses of chemotherapy and radiation required to successfully treat late-stage tumors.

However, the phalanx of extra stem cells protect the intestine and gastrointestinal tract, which means the patient can ingest nutrients, the body can perform other critical functions and the bacterial toxins in the intestine are prevented from entering the blood circulation, Geng said.

These factors could give the patient just enough of an extra edge to survive the stronger doses of chemotherapy and radiation, until the tumor or tumors are eradicated.

In the study, 50-to-75 percent of the mice treated with the molecule survived otherwise lethal doses of chemotherapy. All of the mice that did not receive the molecule died, Geng said.

"If you can keep the gut going, you can keep the patient going longer," Geng said. "Now we have found a way to protect the intestine. The next step is to aim for a 100-percent survival rate in mice who are injected with the molecules and receive lethal doses of chemotherapy and radiation."

Geng's lab has worked with these molecules, called R-spondin1 and Slit2, for more than a decade. These molecules repair tissue in combination with intestinal stem cells residing in the adult intestine.

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Universal law for light absorption in 2-D semiconductors

Working with ultrathin membranes of the semiconductor indium arsenide, a team of researchers with the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) has discovered a quantum unit of photon absorption, which they have dubbed "A_Q," that should be general to all 2D semiconductors, including compound semiconductors of the III-V family that are favored for solar films and optoelectronic devices. This discovery not only provides new insight into the optical properties of 2D semiconductors and quantum wells, it should also open doors to exotic new optoelectronic and photonic technologies.

"We used free-standing indium arsenide membranes down to three nanometers in thickness as a model material system to accurately probe the absorption properties of 2D semiconductors as a function of membrane thickness and electron band structure," says Ali Javey, a faculty scientist in Berkeley Lab's Materials Sciences Division and a professor of electrical engineering and computer science at the University of California (UC) Berkeley. "We discovered that the magnitude of step-wise absorptance in these materials is independent of thickness and band structure details."

Javey is one of two corresponding authors of a paper describing this research in the Proceedings of the National Academy of Sciences (PNAS). The paper is titled "Quantum of optical absorption in two-dimensional semiconductors." Eli Yablonovitch, an electrical engineer who also holds joint appointments with Berkeley Lab and UC Berkeley, is the other corresponding author. Co-authors are Hui Fang, Hans Bechtel, Elena Plis, Michael Martin and Sanjay Krishna.

Previous work has shown that graphene, a two-dimensional sheet of carbon, has a universal value of light absorption. Javey, Yablonovitch and their colleagues have now found that a similar generalized law applies to all 2D semiconductors. This discovery was made possible by a unique process that Javey and his research group developed in which thin films of indium arsenide are transferred onto an optically transparent substrate, in this case calcium fluoride.

"This provided us with ultrathin membranes of indium arsenide, only a few unit cells in thickness, that absorb light on a substrate that absorbed no light," Javey says. "We were then able to investigate the optical absorption properties of membranes that ranged in thickness from three to 19 nanometers as a function of band structure and thickness."

Using the Fourier transform infrared spectroscopy (FTIR) capabilities of Beamline 1.4.3 at Berkeley Lab's Advanced Light Source, a DOE national user facility, Javey, Yablonovitch and their co-authors measured the magnitude of light absorptance in the transition from one electronic band to the next at room temperature. They observed a discrete stepwise increase at each transition from indium arsenide membranes with an A_Qvalue of approximately 1.7-percent per step.

"This absorption law appears to be universal for all 2D semiconductor systems," says Yablonovitch. "Our results add to the basic understanding of electron-photon interactions under strong quantum confinement and provide a unique insight toward the use of 2D semiconductors for novel photonic and optoelectronic applications."

This research was supported by DOE's Office of Science and the National Science Foundation.

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为什么全世界只有中国人最爱玉呢？

中国人对玉的特殊爱好自古有之，喜爱玉甚于黄金和其它玉石，在古代 “ 君子无故，玉不去身，君子与玉比德焉 ” ，并以玉的温润色泽代表仁慈、坚韧质地象征智慧，不伤人的棱角表示公平正义，敲击时发出的清脆舒畅的乐音是廉直美德的反应。正因为此，自古以来得到人们由衷的偏爱。

玉，都是古老的。世界上最精彩的玉，产于新疆和阗。凝固的玉的龙脉，在大山的腹中，深藏了亿万年。这玉的龙脉是大自然最精彩的结晶。随着天地沧桑，一部分玉的龙脉破山而出，裸露于天地风雨冰雪之间，又呈现出别一种玉的资质。经历了风刀霜剑的挥斫，一部分玉滚落在山涧、河流之中，这玉是一大群星星般的魂魄，人们称之为“仔玉”。这玉是玉的龙脉的孙儿，最具生命力量又历经磨砺。这玉彻心彻骨地和光同尘，与风雨雷电，水火冰雪，相亲相融，是真正承受了天地灵气的人间精魂。玉是大自然对于人类最美好的馈赠，可惜只有中国人对它怦然心动，因为只有中国人发觉了玉的美好，而且倾心倾情。 ca9d80163ed7ad5e5aec3dc78c3aa373_thumb
“ 宁为玉碎，不为瓦全 ” 。这正是玉美的 “ 人化 ” ，它象征高尚的人格，君子的气节，优秀的品德，以及生活的理想，玉的美在深化着人的灵魂。
“ 玉不琢，不成器 ” 。这句话已超越出咏物范围，而成了早就人才的箴言。
“ 和氏之壁 ” ，讲述的何尝是一块玉的故事！歌颂的未必只是卞和识玉的才智，他为了一块 “ 楚山璞 ” 而不畏刖刑，失双脚！多么感天动地的精神！这是在讴歌我们中华民族的坚韧精神和不屈不挠的意志！也是从几千年前哲人口中发出的谆谆告诫： “ 识物，识人！ ”
“ 完璧归赵 ” ，记载的何尝只是蔺相如出使秦国的故事，它颂扬的是一种玉的精神，是人类恪守信约的美德和舍生取义的情操。
玉，因其质美，色美，触美，音美，而在石中称王，为人们所喜爱 . 玉是自然的象征，它集聚是着天、地、虹、日、月的精华，是中国的宇宙观念。它是精神，意念，理想，更是中华民族对美的追求和升华。

生成了亿万年的玉，遇到了中国人之后，才变成了通灵宝玉。而具有人类所有的美好品性的中国人，把玉看作了民族的精魂。因为玉也具备了人类所向往的所有的美好的品性，温文、宁静、含蓄、纯净、坚贞和正气。
中国人爱玉，不仅仅是因为它的稀有或色泽美丽的外观，而是有着更深一层的美学价值：因为玉凝结着人们深深的感情 —— 对故乡的怀念，对祖先的崇拜。这种恋乡怀祖之情，培养了中华民族的人格，孕育着中国传统美学；这个美的传统，一直沿续了数千年，始终焕发着不朽的光彩。
“君子比德于玉”，是中国人一句古训，是中国人与玉一见倾心的真情流泻。中国人活着，像玉一样，去世了，最神圣的悼念，也是“生刍一束，其人如玉”。玉最让人称道的品质还在于玉永远不折不挠。“宁为玉碎，不为瓦全”，是玉最让中国人感动的品性。玉碎了，碎了还是玉！中国人把玉看作了民族魂，近百年不折不挠奋斗，中国人有的就是一种“宁为玉碎，不为瓦全的精神，在这个世界上维持着自己的尊严。具有玉的精神的中国人，是永远也不可战胜的。

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综上所述得到的结论是以下这么几个：

第一，先人之影响．远古时期人们就经常将玉器作为祭祀祖宗和神灵的礼器，这种用玉的传统影响良久．

第二，儒家崇尚＂君子比德于玉＂思想的深远影响．孔子说，玉体现了君子所有的美德，玉就是美德的化身，这时它就已经远远不是普通的石头了．只要是自认为具有君子品德的人，都渴望得到一块美玉．甚至在一段时间内，佩玉品相的好坏甚至与佩玉之人品德的高低相联系．

第三，汉代以后玉能辟邪护佑思想的影响．汉代的人们给玉赋予了一种神奇的功能，认为玉石能有避邪和保佑人们平安的功能，所以很多人都祈望自己能够挂一块玉佩以得到神灵保佑．

第四，美玉的保值增值功能的影响．这些年玉石和玉器的市场价值涨幅惊人，也是导致现如今人们钟爱购买和收藏玉器的一个重要原因．但是，这一影响，是绝对地建立在上述三种影响因素之上的，因为没有先人影响、儒家文化影响、祈求神灵护佑思想的存在，就不可能有那么多人对玉石和玉器趋之若鹜，也不会使玉石玉器价格快速上涨．

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Stem cells in urine easy to isolate and have potential for numerous therapies

July 31, 2013 — Could harvesting stem cells for therapy one day be as simple as asking patients for a urine sample? Researchers at Wake Forest Baptist Medical Center's Institute for Regenerative Medicine and colleagues have identified stem cells in urine that can be directed to become multiple cell types.

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"These cells can be obtained through a simple, non-invasive low-cost approach that avoids surgical procedures," said Yuanyuan Zhang, M.D., Ph.D., assistant professor of regenerative medicine and senior researcher on the project.

Reporting online in the journal Stem Cells, the team successfully directed stem cells from urine to become bladder-type cells, such as smooth muscle and urothelial, the cells that line the bladder. But the urine-derived cells could also form bone, cartilage, fat, skeletal muscle, nerve, and endothelial cells, which line blood vessels. The multipotency of the cells suggests their use in a variety of therapies.

"These stem cells represent virtually a limitless supply of autologous cells for treating not only urology-related conditions such as kidney disease, urinary incontinence and erectile dysfunction, but could be used in other fields as well," said Zhang. "They could also potentially be used to engineer replacement bladders, urine tubes and other urologic organs."

Being able to use a patient's own stem cells for therapy is considered advantageous because they do not induce immune responses or rejection. However, because tissue-specific cells are a very small subpopulation of cells, they can be difficult to isolate from organs and tissues.

Zhang's team first identified the cells, which are a small subset of the many cells found in urine, in 2006. The current research builds on earlier studies by confirming the multipotency of the cells. In addition, the research found that unlike iPS cells or embryonic stem cells, the urine derived-stem cells do not form tumors when implanted in the body, indicating they may be safe for use in patients.

The research involved obtaining urine samples from 17 healthy individuals ranging in age from five to 75 years. Isolating the cells from urine involves minimal processing, according to the authors. Next, they evaluated the cells' ability to become multiple cell types.

Importantly, the cells differentiated into the three tissue layers (endoderm, ectoderm and mesoderm) that are a hallmark of true stem cells and also differentiated into the specific cell types mentioned earlier.

Next, the researchers placed cells that had been differentiated into smooth muscle and urothelial cells onto scaffolds made of pig intestine. When implanted in mice for one month, the cells formed multi-layer, tissue-like structures.

The urine-derived stem cells have markers of mesenchymal cells, which are adult stem cells from connective tissue such as bone marrow. They also have markers for pericytes, a subset of mesenchymal cells found in small blood vessels.

Where do the cells come from? Researchers suspect that the cells originate from the upper urinary tract, including the kidney. Female study participants who had received kidney transplants from male donors were found to have the y chromosome in their urine-derived stem cells, suggesting the kidney as the source of the cells.

"Identifying the origins of the cells will lead to a better understanding of the biology of this multipotent population of mesenchymal cells within the urinary tract system," said Zhang.

Co-researchers were Shantaram Bharadwaj, Ph.D., Guihua Liu, M.D., Ph.D., Yingai Shi, M.D., Ph.D., Rongpei Wu, M.D., Ph.D., Bin Yang, M.D., Ph.D., Anthony Atala, M.D., and Jan Rohozinski, Ph.D ., Wake Forest Baptist; Tong-chan He, M.D., Ph.D., the University of Chicago Medical Center; Yuxin Fan, M.D., Ph.D., and Xinyan Lu, M.D., Baylor College of Medicine; Xiaobo Zhou, Ph.D., the Methodist Hospital Research Institute; and Hong Liu, Ph.D., University of Oklahoma.

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How to put a human on Mars, the Imperial approach Imperial College London Universities - Electronics Research

July 31, 2013

Imperial College Mars - Professor Mark Sephton This is an interesting one. Imperial College London is highlighting some of its academics have helped the BBC to design a mock mission to Mars, for the five part programme How to put a human on Mars.

The aim of the series is examine the design challenges of such missions, such as building a spacecraft that can create artificial gravity on the voyage.

For example, Dr Tom Pike, from the Department Electrical and Electronic Engineering, Professor Mark Sephton (pictured right), from the Department Earth Science and Engineering, and Dr Simon Foster and Martin Archer from the Department of Physics were all involved. Ryan Robinson, from the National Heart & Lung Institute, also demonstrated the effects of weightlessness on the body.

Imperial writes:

The BBC approached Imperial because of its academic expertise in the field of space research. One of the academics involved in the making of the BBC programme was Dr Tom Pike, from the Department Electrical and Electronic Engineering. He has previously worked on two NASA missions to the red planet.
The series explores some of the design challenges of the missions including building a spacecraft that can create artificial gravity on the voyage to prevent muscle wastage in the crew. The researchers also discuss ways of keeping astronauts protected during the voyage from radiation from the Sun, and the challenges of landing a crew safely in Mars’ thin atmosphere.

The documentary was to air on the BBC News channel and BBC World News.

How to put a human on mars

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Physicists discover theoretical possibility of large, hollow magnetic cage molecules

Approximately 25 years ago, scientists first made the discovery of C₆₀ fullerene -- better known as the Buckminster Fullerene -- a molecule composed of 60 carbon molecules that formed a hollow cage. Due to its unique hollow cage structure the molecule offers serious technological potential because it could hold other atoms or small molecules inside, and therefore, be used in applications such as drug delivery.

That potential has since spurred worldwide interest among scientists who have been searching for similar molecules. Although some hollow cage structures have been found, none of them is magnetic. Magnetic properties of the structure are of particular interest because a hollow magnetic structure carrying an embedded atom or molecule can be guided by an external magnetic field and may serve as an effective vehicle for targeted drug delivery.

In a new study, published online on July 22 in The Journal of Chemical Physics, two VCU scientists employing state-of-the-art theoretical methods show that magnetic hollow cages larger than the original C₆₀ fullerene that carry giant magnetic moments are possible. A magnetic moment refers to the measure of the magnetic strength of a cluster.

"The potential benefit of this finding is that it provides a route to the synthesis of molecular magnets with colossal magnetic moments," said co-lead investigator Puru Jena, Ph.D., distinguished professor of physics in the VCU College of Humanities and Sciences. Jena collaborated with Menghao Wu, Ph.D., co-author of the paper and a postdoctoral scholar in the VCU Department of Physics.

"These molecules can be used for targeted non-invasive drug delivery. When assembled, the molecules can also form new high strength magnets for device application," Jena said.

According to Jena, the pair of VCU researchers demonstrated the magnetic moment of the molecule by focusing on hetero-atomic clusters consisting of transition metal atoms such as cobalt (Co) and manganese (Mn) and carbon (C) atoms. In particular, Co₁₂C₆, Mn₁₂C₆, and Mn₂₄C₁₈ clusters consisting of 12 cobalt and six carbon atoms, 12 manganese and six carbon atoms, and 24 manganese and 18 carbon atoms, respectively, carry magnetic moments as large as 14, 38 and 70 Bohr magnetons. In comparison, the magnetic moment of an iron (Fe) atom in crystalline iron is 2.2 Bohr magnetons.

According to Jena, the team is still early in its discovery process.

"There is a long way to go. Experiments first have to be carried out to prove the predictions of our theory," said Jena.

"Ways must be found to synthesize large quantities of these molecules and study their magnetic properties once they are assembled. Finally, these molecules need to be functionalized by embedding desired atoms/molecules for practical applications."

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Dawn of carnivores explains animal boom in distant past

July 31, 2013 — A science team that includes researchers from Scripps Institution of Oceanography at UC San Diego has linked increasing oxygen levels and the rise and evolution of carnivores (meat eaters) as the force behind a broad explosion of animal species and body structures millions of years ago.

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Led by Erik Sperling of Harvard University, the scientists analyzed how low oxygen zones in modern oceans limit the abundance and types of carnivores to help lead them to the cause of the "Cambrian radiation," a historic proliferation of animals 500-540 million years ago that resulted in the animal diversity seen today. The study is published in the July 29 early online edition of the Proceedings of the National Academy of Sciences.

Although the cause of the influx of oxygen remains a matter a scientific controversy, Sperling called the Cambrian radiation that followed "the most significant evolutionary event in the history of animals."

"During the Cambrian period essentially every major animal body plan -- from arthropods to mollusks to chordates, the phylum to which humans belong -- appeared in the fossil record," said Sperling, who is scheduled to join Scripps as a postdoctoral researcher through National Science Foundation support. The authors linked this proliferation of life to the evolution of carnivorous feeding modes, which require higher oxygen concentrations. Once oxygen increased, animals started consuming other animals, stimulating the Cambrian radiation through an escalatory predator-prey "arms race."

Lisa Levin, a professor of biological oceanography at Scripps, along with graduate student researcher Christina Frieder, contributed to the study by providing expertise on the fauna of the ocean's low-oxygen zones, areas that have been increasing in recent decades due to a variety of factors. While the Cambrian radiation exploded with new species and diversification, Levin believes this study suggests the reverse may ensue as oxygen declines and oxygen minimum zones expand.

"This paper uses modern oxygen gradients and their effects on marine worms to understand past evolutionary events" said Levin, director of Scripps's Center for Marine Biodiversity and Conservation and a 1982 Scripps graduate. "However, the study of oxygen's role in the past is also going to help us understand the effects of and manage for changes in ocean oxygen in the future."

As part of the research study, Sperling spent time at Scripps working with Levin and Frieder. He also participated in the San Diego Coastal Expedition (bit.ly/sdcoastex), a cruise led by Frieder aboard the Scripps/U.S. Navy research vessel Melville and funded by the UC Ship Funds program, which offers students unique access to at-sea training and research.

In addition to Sperling, Frieder, and Levin, coauthors of the paper include Akkur Raman of Andhra University (India) and Peter Girguis and Andrew Knoll of Harvard. Funding for the study was provided by Ministry of Earth Sciences, New Delhi, Agouron Geobiology, the National Science Foundation, and NASA.

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