时尚家居频道

2013年9月3日星期二

Biologists show that generosity leads to evolutionary success

Sep. 2, 2013 — With new insights into the classical game theory match-up known as the "Prisoner's Dilemma," University of Pennsylvania biologists offer a mathematically based explanation for why cooperation and generosity have evolved in nature.

Share This:

Their work builds upon the seminal findings of economist John Nash, who advanced the field of game theory in the 1950s, as well as those of computational biologist William Press and physicist-mathematician Freeman Dyson, who last year identified a new class of strategies for succeeding in the Prisoner's Dilemma.

Postdoctoral researcher Alexander J. Stewart and associate professor Joshua B. Plotkin, both of Penn's Department of Biology in the School of Arts and Sciences, examined the outcome of the Prisoner's Dilemma as played repeatedly by a large, evolving population of players. While other researchers have previously suggested that cooperative strategies can be successful in such a scenario, Stewart and Plotkin offer mathematical proof that the only strategies that succeed in the long term are generous ones. They report their findings in PNAS the week of Sept. 2.

"Ever since Darwin," Plotkin said, "biologists have been puzzled about why there is so much apparent cooperation, and even flat-out generosity and altruism, in nature. The literature on game theory has worked to explain why generosity arises. Our paper provides such an explanation for why we see so much generosity in front of us."

The Prisoner's Dilemma is a way of studying how individuals choose whether or not to cooperate. In the game, if both players cooperate, they both receive a payoff. If one cooperates and the other does not, the cooperating player receives the smallest possible payoff, and the defecting player the largest. If both players do not cooperate, they receive a payoff, but it is less than what they would gain if both had cooperated. In other words, it pays to cooperate, but it can pay even more to be selfish.

In the Iterated Prisoner's Dilemma, two players repeatedly face off against one another and can employ different strategies to beat their opponent. In 2012, Press and Dyson "shocked the world of game theory," Plotkin said, by identifying a group of strategies for playing this version of the game. They called this class of approaches "zero determinant" strategies because the score of one player is related linearly to the other. What's more, they focused on a subset of zero determinant approaches they deemed to be extortion strategies. If a player employed an extortion strategy against an unwitting opponent, that player could force the opponent into receiving a lower score or payoff.

Stewart and Plotkin became intrigued with this finding, and last year wrote a commentary in PNAS about the Press and Dyson work. They began to explore a different approach to the Prisoner's Dilemma. Instead of a head-to-head competition, they envisioned a population of players matching up against one another, as might occur in a human or animal society in nature. The most successful players would get to "reproduce" more, passing on their strategies to the next generation of players.

It quickly became clear to the Penn biologists that extortion strategies wouldn't do well if played within a large, evolving population because an extortion strategy doesn't succeed if played against itself.

"The fact that there are extortion strategies immediately suggests that, at the other end of the scale, there might also be generous strategies," Stewart said. "You might think being generous would be a stupid thing to do, and it is if there are only two players in the game, but, if there are many players and they all play generously, they all benefit from each other's generosity."

In generous strategies, which are essentially the opposite of extortion strategies, players tend to cooperate with their opponents, but, if they don't, they suffer more than their opponents do over the long term. "Forgiveness" is also a feature of these strategies. A player who encounters a defector may punish the defector a bit but after a time may cooperate with the defector again.

Stewart noticed the first of these generous approaches among the zero determinant strategies that Press and Dyson had defined. After simulating how some generous strategies would fare in an evolving population, he and Plotkin crafted a mathematical proof showing that, not only can generous strategies succeed in the evolutionary version of the Prisoner's Dilemma, in fact these are the only approaches that resist defectors over the long term.

"Our paper shows that no selfish strategies will succeed in evolution," Plotkin said. "The only strategies that are evolutionarily robust are generous ones."

The discovery, while abstract, helps explain the presence of generosity in nature, an inclination that can sometimes seem counter to the Darwinian notion of survival of the fittest.

"When people act generously they feel it is almost instinctual, and indeed a large literature in evolutionary psychology shows that people derive happiness from being generous," Plotkin said. "It's not just in humans. Of course social insects behave this way, but even bacteria and viruses share gene products and behave in ways that can't be described as anything but generous."

"We find that in evolution, a population that encourages cooperation does well," Stewart said. "To maintain cooperation over the long term, it is best to be generous."

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

We have built up long term business relationship with about many companies which are stockers and authorized agents. we have a steady and reliable supply to meet customer's demands to the greatest extent .Confidently, we are able to lower your cost and support your business with our years of professional service.

SUV System Ltd is Electronic Components Distributor Supplies,Find Quality Electronic Components Supplies Products IC(Integrated Circuits),Connectors,Capacitor,Resistors,Diodes,Transistors,LED at Suvsystem.com. Sourcing Other Energy, Environment, Excess Inventory Products from Manufacturers and Suppliers at Suvsystem.com

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

SUV System Ltd insists on the managing faith ofsincereness,speciality,foresight, win-win,so we build up stable-relationship customers located all over the world, including the States, Europe, Argentina, UAE, Malaysia, Australia,and India etc

we are focus on the following fields,and hope we can help you.

Chip Inductors TOSHIBA Diodes Diodes Inc Rectifier Diodes Vishay resistors ST Transistors NXP Diodes Schottky Diodes Transistors Resistors Renesas parts IC PANASONIC BB IC AD IC LITTELFUSE Diodes Atmel IC Chip Fuses Thin Film Resistors DIODES Transistors TDK IC Cypress IC Connectors Capacitor INTERSIL IC About US ST Diodes Texas Instruments(TI) IC Zener Diodes NEC Diodes FAIRCHILD diodes components LINEAR IC Industrial IC NS IC Voltage Regulators Transistors PANASONIC Resistors Digital Transistors IR Diodes Kingbrigt LED TI IC
http://www.suvsystem.com/a/5451.aspx

Genetic reproductive barriers: Long-held assumption about emergence of new species questioned

Sep. 2, 2013 — Darwin referred to the origin of species as "that mystery of mysteries," and even today, more than 150 years later, evolutionary biologists cannot fully explain how new animals and plants arise.

Share This:

For decades, nearly all research in the field has been based on the assumption that the main cause of the emergence of new species, a process called speciation, is the formation of barriers to reproduction between populations.

Those barriers can be geographic -- such as a new mountain, river or glacier that physically separates two populations of animals or plants -- or they can be genetic differences that prevent incompatible individuals from producing fertile offspring. A textbook example of the latter is the mule; horses and donkeys can mate, but their offspring are sterile.

But now a University of Michigan biologist and a colleague are questioning the long-held assumption that genetic reproductive barriers, also known as reproductive isolation, are a driving force behind speciation. Their study is scheduled for online publication in the Proceedings of the National Academy of Sciences on Sept. 2.

"Most research on the formation of species has assumed that these types of reproductive barriers are a major cause of speciation. But our results provide no support for this, and our study is actually the first direct test of how these barriers affect the rate at which species form," said Daniel Rabosky, assistant professor in the U-M Department of Ecology and Evolutionary Biology and a curator of herpetology at the Museum of Zoology.

Rabosky and Daniel Matute of the University of Chicago reasoned that if genetic barriers to reproduction are a leading cause of new species, then groups of organisms that quickly accumulate those genes should also show high rates of species formation.

They tested that idea by comparing speciation rates to genetic indicators of reproductive isolation in birds and fruit flies. They chose birds and fruit flies because extensive data sets on interspecies breeding experiments exist for both groups. The researchers used evolutionary tree-based estimates of speciation rates for nine major fruit fly groups and two-thirds of known bird species.

Rabosky and Matute created computer models to carry out the comparison, and the results surprised them.

"We found no evidence that these things are related. The rate at which genetic reproductive barriers arise does not predict the rate at which new species form in nature," Rabosky said. "If these results are true more generally -- which we would not yet claim but do suspect -- it would imply that our understanding of species formation is extremely incomplete because we've spent so long studying the wrong things, due to this erroneous assumption that the main cause of species formation is the formation of barriers to reproduction.

"To be clear, reproductive barriers are still important on some level. All sorts of plants and animals live together in the same place, which couldn't happen without reproductive barriers. But our results question whether genetic reproductive barriers played a major role in how those species formed in the first place."

While speciation is often defined as the evolution of reproductive isolation, the new findings suggest that a broader definition may be needed, Rabosky and Matute conclude.

Over the last decade or so, the pursuit of the genetic underpinnings of speciation has led to reports on the discovery of a handful of "speciation genes," defined as genes that contribute to reproductive isolation between species. The studies include a 2008 Nature paper that reported the first speciation gene in a mammal.

But if the findings of Rabosky and Matute prove to be more widely applicable to other organisms, speciation genes probably play a minimal role in the formation of species, they said.

"The whole enterprise of finding 'speciation genes' is potentially irrelevant to understanding the origin of species," Rabosky said. "But our study is certainly not going to be the final word on this. If anything, our results indicate that a lot more data will be needed before we can conclusively link the mechanisms we usually study in the lab to the patterns of species formation we see in the natural world."

The researchers speculated that part of what is missing from speciation studies is, paradoxically, extinction. Some researchers have suggested that speciation might be limited primarily by factors associated with the persistence of new species. These models propose that it is relatively easy for a species to split into new species, but the vast majority of new species do not persist over geological timescales.

The research reported in PNAS was supported by the Miller Institute for Basic Research in Science at the University of California-Berkeley, the National Science Foundation and the Chicago Fellows Program at the University of Chicago.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

Freescale Semiconductor Ligitek LED LED part Fairchild Semiconductor Transistors ON Diodes DIODES Transistors Fast Recovery Diodes AD IC Electronic News BB IC Transistors Freescale Infineon Technologies Transistors MAXIM IC Dialight LED SANYO IC ON Transistors ALTERA IC Multi-units Transistors Military IC INTERSIL IC NEC Diodes Discrete Semiconductor Transistors Diodes Inc PANASONIC Chip Fuses Fleld Effect Transistors Diodes Civil IC chip Filter saws Resistor Arrays ROHM Resistors Switches TDK IC Thin Film Resistors Thick Film Resistors IR Diodes Schottky Diodes LINEAR IC Microchip IC ELPIDA IC
http://www.suvsystem.com/a/5449.aspx

Prehistoric climate shift linked to cosmic impact

The event took place about 12,900 years ago, at the beginning of the Younger Dryas period, and marks an abrupt global change to a colder, dryer climate, with far-reaching effects on both animals and humans, the scientists say. In North America the big animals, including mastodons, camels, giant ground sloths, and saber-toothed cats, all vanished. Their human hunters, known to archaeologists as the Clovis people, set aside their heavy-duty spears and turned to a hunter-gatherer subsistence diet of roots, berries, and smaller game.

"The Younger Dryas cooling is a very intriguing event that impacted human history in a profound manner," says Mukul Sharma, a professor in the Department of Earth Sciences and one of the authors of a new paper published in the Proceedings of the National Academy of Sciences (PNAS). "Environmental stresses may also have caused Natufians in the Near East to settle down for the first time and pursue agriculture."

That these powerful environmental changes occurred is not in dispute, but there has been controversy over why they happened. The new PNAS paper focuses on one cause: a comet or meteor striking Earth.

The classical view of the Younger Dryas cooling interlude has been that a surge of meltwater from the North American ice sheet was behind it all. According to this theory, a large quantity of fresh water accumulated behind an ice dam. The dam suddenly ruptured and dumped all this water into the Atlantic Ocean. The sudden influx is thought to have shut down the ocean currents that move tropical water northward, resulting in the cold, dry climate of the Younger Dryas.

However, Sharma and his colleagues from Dartmouth and other institutions have discovered conclusive evidence linking an extraterrestrial impact with this environmental transformation. The PNAS paper presents a scenario in which a meteor or a comet collided with Earth.

The report focuses on spherules, droplets of solidified molten rock expelled by the impact. The spherules in question were recovered from Younger Dryas boundary layers at sites in Pennsylvania and New Jersey, the layers having been deposited at the beginning of the period. The geochemistry and mineralogy profiles of the spherules are identical to rock found in southern Quebec, where Sharma and his colleagues say the impact took place.

"What is exciting in our paper is that we have for the first time narrowed down the region where a Younger Dryas impact did take place," says Sharma, "even though we have not yet found its crater." There is a known impact crater in Quebec -- the 4-kilometer-wide Corossal crater. However, based on mineralogical and geochemical studies, it is not the impact source for the material found in Pennsylvania and New Jersey.

People have written about many impacts in different parts of the world based on the presence of spherules. "It may well have taken multiple concurrent impacts to bring about the extensive environmental changes of the Younger Dryas," says Sharma. "However, to date no impact craters have been found, and our research will help track one of them down."

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

MOTOROLA IC Dialight LED chip Filter saws VISHAY IC Fairchild Semiconductor Transistors Resistor Networks Switches Ligitek LED Schottky Diodes Renesas parts IC ROHM Resistors Rectifier Diodes SANYO IC ALTERA IC Kingbrigt LED Fast Recovery Diodes DIODES Transistors Thin Film Resistors TOSHIBA Transistors Civil IC Chip Fuses High Precision Resistors BB IC Chip Ferrite Beads HARRIS IC Atmel IC Transistors Freescale INTERSIL IC Resistors MAXIM IC Fleld Effect Transistors Digital Transistors ON Transistors Diodes Vishay resistors Industrial IC Other Parts Low Ohmic Resistors YAGEO Resistors components
http://www.suvsystem.com/a/5447.aspx

Average height of European males has grown by 11 centimeters in just over a century

Timothy J. Hatton, Professor of Economics at the University of Essex and the Research School of Economics at Australian National University in Canberra, examined and analysed a new dataset for the average height (at the age of around 21) of adult male birth cohorts, from the 1870s to 1980, in fifteen European countries. The data were drawn from a variety of sources. For the most recent decades the data were mainly taken from height-by-age in cross sectional surveys. Meanwhile, observations for the earlier years were based on data for the heights of military conscripts and recruits. The data is for men only as the historical evidence for women's heights is severely limited.

Professor Hatton said, "Increases in human stature are a key indicator of improvements in the average health of populations. The evidence suggests that the improving disease environment, as reflected in the fall in infant mortality, is the single most important factor driving the increase in height. The link between infant mortality and height has already been demonstrated by a number of studies." Infant mortality rates fell from an average of 178 per thousand in 1871-5 to 120 per thousand in 1911-15. They then plummeted to 41 in 1951-5 and 14 in 1976-80.

In northern and middle European countries (including Britain and Ireland, the Scandinavian countries, Netherlands, Austria, Belgium, and Germany) there was a "distinct quickening" in the pace of advance in the period spanning the two World Wars and the Great Depression. This is striking because the period largely predates the wide implementation of major breakthroughs in modern medicine and national health services. One possible reason, alongside the crucial decline in infant mortality, for the rapid growth of average male height in this period was that there was a strong downward trend in fertility at the time, and smaller family sizes have already been linked with increasing height.

Other factors in the increase in average male height include an increased income per capita; more sanitary housing and living conditions; better general education about health and nutrition (which led to better care for children and young people within the home); and better social services and health systems.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

Digital Transistors Bipolar Transistors ON Transistors Connectors Low Ohmic Resistors NEC Transistors HARRIS IC INTERSIL IC Electronic News ON Diodes Fleld Effect Transistors LED NXP Diodes Capacitor Resistor Arrays FAIRCHILD diodes BB IC INFLNEON Diodes Infineon Technologies Transistors Diodes MOTOROLA IC IDT IC Switches chip Filter saws LITTELFUSE Diodes Schottky Diodes Rectifier Diodes Microchip IC MURATA IC Freescale Semiconductor IR Diodes Thick Film Resistors ST Diodes Resistor Networks High Precision Resistors AVX Resistors ALTERA IC Dialight LED Chip Inductors TOSHIBA Transistors
http://www.suvsystem.com/a/5441.aspx

2013年9月2日星期一

Distribution Acal buys Young Electronics in cash deal

2013/09/02

Acal has acquired fellow UK-based distributor Young Electronics for £1.7m from H Young Holdings in a cash deal.

Young Electronics Group (YEG) sells solid state lighting, power, power cords and custom cable assembly. It also has own label products sales.

“The acquisition of the Young Electronics Group expands our existing technology areas as well as adding new ones,” said Nick Jefferies, Chief Executive of Acal plc.

Based in High Wycombe and trading predominately in the UK and Ireland, YEG made a small operating loss during its year ended 31 December 2012.

The business will be integrated into Acal’s Electronics division to generate operational synergies as well as opportunities for cross selling. Integration is expected to complete around the end of the financial year.

“By integrating the operations into our Electronics division, we expect to create efficiency savings whilst retaining the commercial and technical capabilities,” said Jefferies.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

Xilinx IC YAGEO Resistors TI IC Fleld Effect Transistors Cypress IC AD IC Freescale Semiconductor Industrial IC MOTOROLA IC ST Diodes Capacitor Current Sensors Resistors Zener Diodes Diodes Inc Metal Can Packages Transistors ALTERA IC Renesas parts IC Dialight LED Voltage Regulators Transistors Chip Ferrite Beads Military IC Fast Recovery Diodes Multi-units Transistors BB IC IR transistor ON Diodes Switches MAXIM IC components Schottky Diodes ELPIDA IC INTERSIL IC Low Ohmic Resistors MURATA IC SANYO IC Transistors NEC Transistors NEC Diodes INFLNEON Diodes DIODES Transistors
http://www.suvsystem.com/a/5440.aspx

Manufacturing Farnell offers USB soldering iron

2013/09/02

USB solderingIron 559 This is the world’s first USB-powered soldering iron, claims stockist Farnell.

Made by MegaPower, it is is designed for quick repairs in the field and lab for fine pitch surface-mount components, and can also be powered from a 9V batter.

“The iron achieves 480°C in 20 seconds and has 5W power consumption instead of 40W,” said Farnell.

There is an LED to illuminate the work, and an on-off switch.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

FPGA / PLD Lattice aims to widen use of MIPI camera interface

2013/09/02

CMOS Diagram 1 Lattice Semiconductor has introduced reference designs which it said will simplify camera system design based on the MIPI (Mobile Industry Processor Interface) standard.

The FPGA-based reference designs can allow designers to use image sensors that are not designed for the mobile market.

“As an example, a high end smartphone could incorporate a DSLR type camera. In this case, the image sensor is bridged to a MIPI-based applications processor via a Lattice FPGA. The inverse is also true where MIPI-based components can be linked to non-MIPI based processors or SoCs,” said the company.

“Manufacturers would like to leverage mobile display, applications processor, or camera components, but the interfaces for these low cost system components often present a challenge,” said Ted Marena, director of solutions marketing at Lattice.

“The fact is, until MIPI becomes the dominant interface for the broad market, customers are going to need a bridge between different interface technologies,” said Marena.

Lattice will be a presenting its MIPI designs at the Qualcomm Uplinq 2013 conference’s Hardware Day on Sept. 3.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

Research Direct brain to brain communication over the Internet

2013/09/02

WashintonBrainToBrainPic 600 University of Washington researchers has established a non-invasive brain-to-brain interface, with one researcher’s thoughts controlling another’s hand motion over the Internet.

Key elements of the experiment were a electrode cap on the head of Professor Rajesh Rao, hooked up to an electroencephalograph, and a transcranial magnetic stimulation coil over the left motor cortex of researcher Andrea Stocco.

Rao looked at a computer screen and played a simple video game with his mind, with the electroencephalograph moving a cursor on the screen via custom analysis algorithms.

When he was supposed to fire at a target, without actually moving his hand, he imagined moving his right hand, causing a cursor to hit the virtual ‘fire button’.

On the other side of the campus, Stocco’s right index finger involuntary moved to push the space bar on the keyboard in front of him, causing the game’s gun to fire. Stocco wore noise-cancelling earbuds and wasn’t looking at a computer screen, and compared the feeling of his hand moving to that of a nervous tic.

WashingtonBrainToBrain 480 “It was both exciting and eerie to watch an imagined action from my brain get translated into actual action by another brain,” said Rao. “The next step is having a more equitable two-way conversation directly between the two brains.”

Rao said this technology only reads certain kinds of simple brain signals. The pair plan to conduct an experiment that would transmit more complex information from one brain to the other. If that works, they then will conduct the experiment on a larger pool of subjects.

The researchers credit earlier work: brain-to-brain communication between two rats at Duke University and communication between a human and a rat at Harvard, and believe theirs is the first demonstration of human-to-human brain interfacing.

Rao has been working on brain-computer interfacing for more than 10 years and just published a book on the subject.

The brain communication project has a website which includes photos and video.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

Renesas parts IC INTERSIL IC Cypress IC IC(Integrated Circuits) About US Connectors Fairchild Semiconductor Transistors NS IC TDK IC Resistor Networks Vishay resistors High Precision Resistors Freescale Semiconductor MURATA IC MAXIM IC HARRIS IC Transistors MOTOROLA IC Kingbrigt LED BB IC Resistors Xilinx IC SANYO IC Switches Thick Film Resistors Resistor Arrays Switching Diodes AD IC Atmel IC Multi-units Transistors Electronic News LITTELFUSE Diodes ELPIDA IC Civil IC Chip Ferrite Beads Microchip IC chip Filter saws TOSHIBA Transistors LINEAR IC LED
http://www.suvsystem.com/a/5437.aspx

Business ARM and CSR founders join Blu Wireless

2013/09/02

Sir Robin Saxby, founding CEO of ARM, and Glenn Collinson, co-founder of CSR, are to join the board of Blu Wireless, the Bristol wireless start up with a 60GHz band backhaul product for LTE small cell deployment.

Also joining the board is Professor Andrew Nix, head of the Communication Systems & Networks Group at Bristol University.

Blu Wireless recently secured $3 million of funding to take its HYDRA baseband chip IP to market. HYDRA uses a heterogeneous multiprocessing architecture optimised to deliver a flexible, power-efficient and low-cost implementation of these multi-gigabit communication standards.

“The deep technical and market expertise that these industry veterans bring to us gives us the strategic insights that will significantly accelerate our development cycle,”
Says Blu Wireless CEO, Henry Nurser, “their backing is a strong endorsement of both our business model and our technological offering.”

Blu Wireless is about developing soft macro IP for Gigabit WiFi – WiGig, “We’re selling soft macros which can be easily absorbed into customers’ design flows.”

“The problem was how to efficiently address multi-gigabit baseband processing,” says Nurser, “a lot of people are doing hard-wired implementations but these are totally inflexible, so we set out to do something with the same power as hard-wired but significantly more flexible.”

The application is backhaul for LTE small cells using the unlicensed 60GHz band to ensure low-cost for the carriers.

The technology permits 1 – 2 Gbps over 300 metres. “Our design is an ideal fit for that application,” says Nurser.

BluWireless has had £270,000 in Angel funding,and three lead customers one of whom is funding prototype development. It has received £350,000 in billings so far from consultancy and from licensing some core algorithms to use in the backhaul space.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

Capacitor Rectifier Diodes Switching Diodes Freescale Semiconductor LINEAR IC Renesas parts IC VISHAY IC SANYO IC NXP Transistors Discrete Semiconductor Transistors IDT IC Metal Can Packages Transistors Switches MOTOROLA IC Resistor Networks Xilinx IC ST Transistors Thick Film Resistors LED part Atmel IC Other Parts IR transistor LED Chip Fuses components AD IC Infineon Technologies Transistors TDK IC ROHM Resistors Resistor Arrays IC(Integrated Circuits) ELPIDA IC Fleld Effect Transistors Fairchild Semiconductor Transistors Resistors NXP Diodes Chip Ferrite Beads ST Diodes YAGEO Resistors Microchip IC
http://www.suvsystem.com/a/5433.aspx

Scientists show how antibiotics enable pathogenic gut infections

A number of intestinal pathogens can cause problems after antibiotic administration, said Justin Sonnenburg, PhD, assistant professor of microbiology and immunology and the senior author of the study, to be published online Sept. 1 in Nature. Graduate students Katharine Ng and Jessica Ferreyra shared lead authorship.

"Antibiotics open the door for these pathogens to take hold. But how, exactly, that occurs hasn't been well understood," Sonnenburg said.

In the first 24 hours after administration of oral antibiotics, a spike in carbohydrate availability takes place in the gut, the study says. This transient nutrient surplus, combined with the reduction of friendly gut-dwelling bacteria due to antibiotics, permits at least two potentially deadly pathogens to get a toehold in that otherwise more forbidding environment.

In the past decade or so, much has been learned about the complex microbial ecosystem that resides in every healthy mammal's large intestine, including ours. The thousands of distinct bacterial strains that normally inhabit this challenging but nutrient-rich niche have adapted to it so well that we have difficulty living without them. They manufacture vitamins, provide critical training to our immune systems and even guide the development of our own tissues. Antibiotics decimate this gut-microbe ecosystem, which begins bouncing back within a few days but may take a month or more to regain its former numbers. And the ecosystem appears to suffer the permanent loss of some of its constituent bacterial strains.

It is thought that our commensal, or friendly, bacteria serve as a kind of lawn that, in commandeering the rich fertilizer that courses through our gut, outcompetes the less-well-behaved pathogenic "weeds." It has also been suggested that our commensal bugs secrete pathogen-killing factors. Another theory holds that the disruption of our inner microbial ecosystem somehow impairs our immune responsiveness.

"While these hypotheses are by no means mutually exclusive, our work specifically supports the suggestion that our resident microbes hold pathogens at bay by competing for nutrients," Sonnenburg said.

When that defense falters, as it does shortly after a course of antibiotics begins, marauding micro-organisms such as salmonella or Clostridium difficile can establish beachheads. Once they reach sufficient numbers, these two parasitic invaders can mount intentional campaigns to induce inflammation, a condition that impairs the restoration of our normal gut ecosystem but in which salmonella and C. difficile have learned to prosper.

The particular nutrients Sonnenburg's team looked at were sialic acid and fucose, a couple of members of the sugar family. While not household words like glucose, fructose or lactose, these two sugar varieties are produced in every cell in our bodies and are absolutely necessary for our healthy survival. They are also found in meat, eggs and dairy products.

Cells that line the gut extrude long chains consisting of exotic and familiar sugars linked together and known by a catch-all term: mucus. This homely product serves two valuable functions. First, by coating the inside intestinal wall, mucus forms a reasonably impervious protective barrier to keep the resident microbes, which serve useful purposes inside the gastrointestinal tract, from getting out of the gut and into the bloodstream, where they could be lethal. But the mucus has a second function as well: It gives our resident microbes a guaranteed source of various sugars, like sialic acid and fucose, that they can snap off and use in a number of ways. They can, for example, break these sugar molecules down and derive energy from them.

"Our gut microbes have become very adept at eating mucus," Sonnenburg said.

For the Nature study, he and his associates experimented on mice that had been born and bred in a germ-free environment. These mice's guts were devoid of bacteria, unlike normal mice, which harbor hundreds of bacterial species in their bowels just as humans do. Into these germ-free mice the Stanford investigators introduced a single bacterial strain, Bacteroides thetaiotaomicron. B. theta is a member of a well-studied and important class of commensal microbes that populate the human gut. It has the enzymes necessary to pry sugar molecules loose from the mucus chains streaming from the gut lining. In the case of sialic acid, it lacks the enzymes that would allow it to break down either of these two molecules for its own snacking purposes.

Chipping off sugar molecules it can't chop up for food may seem a waste of B. theta's time. But in a normal gut, there are plenty of other microbes that have tools for digesting sialic acid and fucose, and that can produce other materials B. theta needs. It's a barter system, which ecologists call symbiosis. (It also may just be that B. theta lops off these sugar residues to get to other, edible sugar residues underneath.)

In a series of separate experiments, the investigators introduced either S. typhimurium (a salmonella strain) or C. difficile in the B. theta-loaded experimental mice. Both types of bacteria can cause severe and potentially life-threatening disease associated with antibiotic use. They also share a common capacity for using sialic acid as an energy source, but not for slicing it off intestinal mucus. After discovering that C. difficile can neither liberate nor lunch on fucose, the Sonnenburg team focused their efforts on determining how the two pathogens make use of sialic acid.

Introducing one friendly and one pathogenic bacterial strain into the guts of the formerly germ-free mice, the scientists were able to show that, in this approximation of an antibiotic-decimated gut-microbe ecosystem, the levels of sialic acid soared to high levels in the absence of a complete set of intestinal microbes that ordinarily would keep those levels from climbing. In the presence of these sugars and absence of competition, both pathogens were able to replicate more rapidly. B. theta generated a sialic-acid surplus that, in the absence of the other hundreds of normal bacterial species, were bequeathed to the pathogenic strains.

When the researchers investigated the effects of antibiotics on mice with normal intestinal ecosystems, they saw the same sialic-acid spike -- and pathogen population explosion -- in the wake of the carnage. If the mice were not exposed to the pathogens, but only treated with antibiotics, the sialic acid concentrations returned to their original levels after about three days post-antibiotic treatment as commensals began to recover.

"The bad guys in the gut are scavenging nutrients that were liberated by the good guys, who are casualties of the collateral damage incurred by antibiotics," said Sonnenburg. "Antibiotics cause our friendly gut bacteria to unwittingly help these pathogens.

"We believe that bacterial pathogens in the gut cause disease in two steps," he continued. "Others have shown that once these pathogens attain sufficient numbers, they use inflammation-triggering tricks to wipe out our resident friendly microbes -- at no cost to the pathogens themselves, because they've evolved ways to deal with it. But first, they have to surmount a critical hurdle: In the absence of the inflammation they're trying to induce, they have to somehow reach that critical mass. Our work shows how they go about it after a dose of antibiotics. They take advantage of a temporary spike in available sugars liberated from intestinal mucus left behind by slain commensal microbes."

Sonnenburg said he thinks researchers may someday be able to find drugs that, co-administered with antibiotics, could inhibit the enzymes our friendly gut-bugs use to liberate sialic acid from intestinal mucus, so that a pathogen-nourishing spike doesn't occur. Alternatively, probiotics in the form of bacterial strains that are especially talented at digesting sialic acid could achieve a similar effect.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

TDK IC IR transistor Current Sensors Resistors Freescale Semiconductor LED part TOSHIBA Transistors INTERSIL IC ALTERA IC BB IC Voltage Regulators Transistors TOSHIBA Diodes Transistors Freescale Connectors Thick Film Resistors Xilinx IC ROHM Resistors AVX Resistors NEC Diodes Transistors Chip Ferrite Beads NXP Diodes About US Bipolar Transistors SANYO IC Switching Diodes ELPIDA IC Civil IC Ligitek LED INFLNEON Diodes Industrial IC Fast Recovery Diodes Microchip IC LED NXP Transistors Zener Diodes Military IC Diodes Thin Film Resistors LITTELFUSE Diodes Chip Inductors
http://www.suvsystem.com/a/5430.aspx

订阅：博文 (Atom)