Quantum physics enables perfectly secure cloud computing
January 19, 2012
Researchers have succeeded in combining the power of quantum computing with the security of quantum cryptography and have shown that perfectly secure cloud computing can be achieved using the principles of quantum mechanics. They have performed an experimental demonstration of quantum computation in which the input, the data processing, and the output remain unknown to the quantum computer. The international team of scientists will publish the results of the experiment, carried out at the Vienna Center for Quantum Science and Technology (VCQ) at the University of Vienna and the Institute for Quantum Optics and Quantum Information (IQOQI), in the forthcoming issue of Science.
Quantum computers are expected to play an important role in future information processing since they can outperform classical computers at many tasks. Considering the challenges inherent in building quantum devices, it is conceivable that future quantum computing capabilities will exist only in a few specialized facilities around the world – much like today’s supercomputers. Users would then interact with those specialized facilities in order to outsource their quantum computations. The scenario follows the current trend of cloud computing: central remote servers are used to store and process data – everything is done in the “cloud.” The obvious challenge is to make globalized computing safe and ensure that users’ data stays private.
The latest research, to appear in Science, reveals that quantum computers can provide an answer to that challenge. “Quantum physics solves one of the key challenges in distributed computing. It can preserve data privacy when users interact with remote computing centers,” says Stefanie Barz, lead author of the study. This newly established fundamental advantage of quantum computers enables the delegation of a quantum computation from a user who does not hold any quantum computational power to a quantum server, while guaranteeing that the user’s data remain perfectly private. The quantum server performs calculations, but has no means to find out what it is doing – a functionality not known to be achievable in the classical world.
The scientists in the Vienna research group have demonstrated the concept of “blind quantum computing” in an experiment: they performed the first known quantum computation during which the user’s data stayed perfectly encrypted. The experimental demonstration uses photons, or “light particles” to encode the data. Photonic systems are well-suited to the task because quantum computation operations can be performed on them, and they can be transmitted over long distances.
The process works in the following manner. The user prepares qubits – the fundamental units of quantum computers – in a state known only to himself and sends these qubits to the quantum computer. The quantum computer entangles the qubits according to a standard scheme. The actual computation is measurement-based: the processing of quantum information is implemented by simple measurements on qubits. The user tailors measurement instructions to the particular state of each qubit and sends them to the quantum server. Finally, the results of the computation are sent back to the user who can interpret and utilize the results of the computation. Even if the quantum computer or an eavesdropper tries to read the qubits, they gain no useful information, without knowing the initial state; they are “blind.”
The research at the Vienna Center for Quantum Science and Technology (VCQ) at the University of Vienna and at the Institute for Quantum Optics and Quantum Information (IQOQI) of the Austrian Academy of Sciences was undertaken in collaboration with the scientists who originally invented the protocol, based at the University of Edinburgh, the Institute for Quantum Computing (University of Waterloo), the Centre for Quantum Technologies (National University of Singapore), and University College Dublin.
Publication: “Demonstration of Blind Quantum Computing” Stefanie Barz, Elham Kashefi, Anne Broadbent, Joseph Fitzsimons, Anton Zeilinger, Philip Walther. DOI: 10.1126/science.1214707
Contact: Stefanie Barz
stefanie.barz@univie.ac.at
University of Vienna
Research reveals power of the subconscious in human fear
January 18, 2012
The human subconscious has a bigger impact than previously thought on how we respond to danger, according to research led by the University of Exeter. Published today (I8 January), the study shows that our primitive response to fear can contradict our conscious assessment of danger.
The findings have implications for how anxiety disorders, such as phobias, are treated. The research also suggests we share a primitive response to fear with other animals, despite being able to consciously anticipate and assess danger.
Participants recruited to the study sat in front of a screen, on which a coloured shape sometimes appeared. Half the time, the image was accompanied by a mild electric shock. For the rest of the time, the image appeared but no shock was given.
During the trial they were asked to rate whether or not they expected a shock to be given and their ‘skin conductance’ was monitored. This technique measures the variation in the electrical activity of the sweat glands in the skin, which is an indication of the state of arousal of the sympathetic nervous system. In other words, it gives us a reading of a person’s emotional state.
Following a series of trials involving shocks, participants were more likely to predict they would not receive a shock when the image was next shown. The complementary result was that they generally anticipated receiving a shock if they had not had one for the last few images. This phenomenon of expecting good luck after a run of bad luck and vice versa, is known as the ‘gambler’s fallacy’.
The skin conductance responses revealed the opposite pattern. Following a series of shocks accompanying the image, their physical responses to the next image shown suggested participants were more likely to expect another shock, but that they were less likely to expect a shock after a run of no-shock trials. This pattern of responding is consistent with ‘associative learning’: associating a visual cue with a significant event, a phenomenon that is well known in animals.
Previously it has been thought that, when using this type of procedure, humans respond differently from animals because we rely on conscious reasoning, rather than associative learning to generate our expectations. This study suggests that, despite our sophisticated mental capabilities, our responses are in fact driven by these more primitive processes when in danger.
Lead author, Professor Ian McLaren of the University of Exeter said: “This research clearly shows that, in these circumstances, our reaction to a fear-provoking stimulus depends on a primitive response caused by associative learning. This is something we share with other animals.
“This could have important practical implications. Now that we know that associative processes are implicated in our response to fear-inducing stimuli, we need to consider the implications for the ways in which we treat anxiety and phobias.”
Contact: Sarah Hoyle
s.hoyle@exeter.ac.uk
44-013-927-22062
University of Exeter
‘Miracle tree’ substance produces clean drinking water inexpensively and sustainably
January 18, 2012
A natural substance obtained from seeds of the “miracle tree” could purify and clarify water inexpensively and sustainably in the developing world, where more than 1 billion people lack access to clean drinking water, scientists report. Research on the potential of a sustainable water-treatment process requiring only tree seeds and sand appears in ACS’ journal Langmuir.
Stephanie B. Velegol and colleagues explain that removing the disease-causing microbes and sediment from drinking water requires technology not always available in rural areas of developing countries. For an alternative approach, Velegol looked to Moringa oleifera, also called the “miracle tree,” a plant grown in equatorial regions for food, traditional medicine and biofuel. Past research showed that a protein in Moringa seeds can clean water, but using the approach was too expensive and complicated. So Velegol’s team sought to develop a simpler and less expensive way to utilize the seeds’ power.
To do that, they added an extract of the seed containing the positively charged Moringa protein, which binds to sediment and kills microbes, to negatively charged sand. The resulting “functionalized,” or “f-sand,” proved effective in killing harmful E. coli bacteria and removing sediment from water samples. “The results open the possibility that f-sand can provide a simple, locally sustainable process for producing storable drinking water,” the researchers say.
The authors acknowledge funding from the National Science Foundation, and the U. S. Environmental Protection Agency.
Contact: Michael Bernstein
m_bernstein@acs.org
202-872-6042
American Chemical Society
Ancient popcorn discovered in Peru
January 18, 2012
People living along the coast of Peru were eating popcorn 1,000 years earlier than previously reported and before ceramic pottery was used there, according to a new paper in the Proceedings of the National Academy of Sciences co-authored by Dolores Piperno, curator of New World archaeology at the Smithsonian’s National Museum of Natural History and emeritus staff scientist at the Smithsonian Tropical Research Institute.
Some of the oldest known corncobs, husks, stalks and tassels (male flowers), dating from 6,700 to 3,000 years ago were found at Paredones and Huaca Prieta, two mound sites on Peru’s arid northern coast. The research group, led by Tom Dillehay from Vanderbilt University and Duccio Bonavia from Peru’s Academia Nacional de la Historia, also found corn microfossils: starch grains and phytoliths. Characteristics of the cobs – the earliest ever discovered in South America – indicate that the sites’ ancient inhabitants ate corn several ways, including popcorn and flour corn. However, corn was still not an important part of their diet.
“Corn was first domesticated in Mexico nearly 9,000 years ago from a wild grass called teosinte,” said Piperno. “Our results show that only a few thousand years later corn arrived in South America where its evolution into different varieties that are now common in the Andean region began. This evidence further indicates that in many areas corn arrived before pots did and that early experimentation with corn as a food was not dependent on the presence of pottery.”
Understanding the subtle transformations in the characteristics of cobs and kernels that led to the hundreds of maize races known today, as well as where and when each of them developed, is a challenge. Corncobs and kernels were not well preserved in the humid tropical forests between Central and South America, including Panama – the primary dispersal routes for the crop after it first left Mexico about 8,000 years ago.
“These new and unique races of corn may have developed quickly in South America, where there was no chance that they would continue to be pollinated by wild teosinte,” said Piperno. “Because there is so little data available from other places for this time period, the wealth of morphological information about the cobs and other corn remains at this early date is very important for understanding how corn became the crop we know today.”
The Smithsonian Tropical Research Institute, headquartered in Panama City, Panama, is a unit of the Smithsonian Institution. The Institute furthers the understanding of tropical nature and its importance to human welfare, trains students to conduct research in the tropics and promotes conservation by increasing public awareness of the beauty and importance of tropical ecosystems. Website: www.stri.si.edu
Contact: Beth King
kingb@si.edu
202-633-4700 x28216
Smithsonian Tropical Research Institute
Potential new therapy approach for hepatitis C identified
January 16, 2012
Researchers at the University of British Columbia have found a new way to block infection from the hepatitis C virus (HCV) in the liver that could lead to new therapies for those affected by this and other infectious diseases.
More than 170 million people worldwide suffer from hepatitis C, the disease caused by chronic HCV infection. The disease affects the liver and is one of the leading causes of liver cancer and liver transplant around the world. HCV is spread by blood-to-blood contact and there is no vaccine to prevent it. Current treatments for the disease are only moderately effective and can cause serious side effects.
“As HCV infects a person, it needs fat droplets in the liver to form new virus particles,” says François Jean, Associate Professor in the Department of Microbiology and Immunology and Scientific Director of the Facility for Infectious Disease and Epidemic Research (FINDER) at UBC. “In the process, it causes fat to accumulate in the liver and ultimately leads to chronic dysfunction of the organ.”
“HCV is constantly mutating, which makes it difficult to develop antiviral therapies that target the virus itself,” says Jean. “So we decided to take a new approach.”
Jean and his team developed an inhibitor that decreases the size of host fat droplets in liver cells and stops HCV from “taking residence,” multiplying and infecting other cells.
“Our approach would essentially block the lifecycle of the virus so that it cannot spread and cause further damage to the liver,” says Jean. The team’s method is detailed in the journal PLoS Pathogens.
According to Jean, HCV is one of a number of viruses that require fat to replicate in the human body. This new approach to curbing the replication of HCV could translate into similar therapies for other related re-emerging viruses that can cause serious and life threatening infections in humans, such as dengue virus. Dengue is endemic in more than 100 countries, with approximately 2.5 billion people at risk of infection globally. In some countries, Dengue has become the leading cause of child mortality.
The research was supported by the Canadian Institutes of Health Research (CIHR) through grants and scholarships and by the Michael Smith Foundation for Health Research (MSFHR) through its Junior Trainee Award. The study is available at http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1002468
Contact: Brian Lin
brian.lin@ubc.ca
604-822-2234
University of British Columbia
I recognize you! But how did I do it?
January 14, 2012
Are you someone who easily recognises everyone you’ve ever met? Or maybe you struggle, even with familiar faces? It is already known that we are better at recognising faces from our own race but researchers have only recently questioned how we assimilate the information we use to recognise people.
New research by the University of Nottingham Malaysia Campus has shown that when it comes to recognising people the Malaysian Chinese have adapted their facial recognition techniques to cope with living in a multicultural environment.
The study ‘You Look Familiar: How Malaysian Chinese Recognise Faces’ was led by Chrystalle B.Y. Tan, a PhD student at the University of Nottingham Malaysia Campus. The results have been published online in the prestigious scientific journal PloS One, This research is the first PhD student publication for Nottingham’s School of Psychology in Malaysia.
Chrystalle Tan said: “Our research has shown that Malaysian Chinese adopt a unique looking pattern which differed from both Westerners and Mainland Chinese, possibly due to the multicultural nature of the country.”
The ability to recognise different faces may have social and evolutionary advantages. Human faces provide vital information about a person’s identity and characteristics such as gender, age, health and attractiveness. Although we all have the same basic features we have our own distinguishing features and there is evidence that the brain has a specialised mental module dedicated to face processing.
Recognition techniques
Previous research by a group at Glasgow University in Scotland showed that Asians from mainland China use more holistic recognition techniques to recognise faces than Westerners.
- Chinese focus on the centre of the face in the nose area
- Westerners focus on a triangular area between the eyes and mouth
- British born Chinese use both techniques fixating predominantly around either the eyes and mouth, or the nose
Chrystalle said: “The traditional view is that people recognise faces by looking in turn at each eye and then the mouth. This previous research showed us that some Asian groups actually focus on the centre of the face, in the nose area. While Westerners are learning what each separate part of the face looks like – a strategy that could be useful in populations where hair and eye colour vary dramatically, mainland Chinese use a more global strategy, using information about how the features are arranged. Meanwhile British born Chinese use a mixture of both techniques suggesting an increased familiarity with other-race faces which enhances their recognition abilities.”
Eye tracking technology
The study by the School of Psychology at the University of Nottingham Malaysia Campus set out to investigate whether exposure and familiarity with other cultures affects our recognition accuracy and eye movement strategies.
The team used specialised eye tracking technology to investigate the visual strategies used to recognise photographs of faces. They recruited 22 Malaysian Chinese student volunteers from across Nottingham’s Malaysia campus. The results showed that Malaysian Chinese used a unique mixed strategy by focusing on the eyes and nose more than the mouth.
Chrystalle said: “We have shown that Malaysian Chinese adopt a unique looking pattern which differed from both Westerners and mainland Chinese. This combination of Eastern and Western looking patterns proved advantageous for Malaysian Chinese to accurately recognise Chinese and Caucasian faces.”
The study was supervised by Dr Ian Stephen, an expert on face processing and Dr Elizabeth Sheppard, an expert in eye tracking. Dr Stephen said: “We think that people learn how to recognise faces from the faces that they encounter. Although Malaysia is an East Asian country its ethnic composition is highly diverse. The intermediate looking strategy that Malaysian Chinese use allows them to recognise Western faces just as well as Asians.”
Contact: Lindsay Brooke
lindsay.brooke@nottingham.ac.uk
44-115-951-5751
University of Nottingham
Emotional news framing affects public response to crises
January 14, 2012
When organizational crises occur, such as plane crashes or automobile recalls, public relations practitioners develop strategies for substantive action and effective communication. Now, University of Missouri researchers have found that the way in which news coverage of a crisis is framed affects the public’s emotional response toward the company involved.
Glen Cameron, the Maxine Wilson Gregory Chair in Journalism Research and professor of strategic communication at the University of Missouri School of Journalism, along with Hyo Kim of Nanyang Technological University in Singapore, studied the reactions of news readers when exposed to a story about a crisis. One group read an “anger-frame” story that blamed the organization for the crisis. Another group read a “sadness-frame” story that focused on the victims and how they were hurt by the crisis. Cameron and Kim found that those who read the “anger-frame” story read the news less closely and had more negative attitudes toward the company than those exposed to the “sadness-frame” story.
“The distinct emotions induced by different news frames influenced individuals’ information processing and how they evaluated the corporation,” Cameron said.
Cameron and Kim also found that a corporate response to a crisis that focuses on the relief and wellbeing of the victims tends to improve the public’s perceptions of the corporation as compared to the message focusing on the law, justice, and punishment. This was the case regardless of how the initial news was framed (i.e., anger vs. sadness). Cameron says these findings illustrate the importance of controlling the message during a crisis.
“It is important for corporations to put on a human face during crises,” Cameron said. “If a corporation can focus on the well-being of the victims and how the corporation will improve following the crisis, they have a better chance of influencing “sadness-frame” news coverage as opposed to “anger-frame” coverage. If the news coverage remains “sadness-framed,” public perception will stay more positive.”
Cameron says this research is important, not to help corporations shirk responsibility, but rather to handle crisis situations in the best way possible.
“Crises are going to happen,” Cameron said. “Unfortunately, planes will crash and there will be oil spills. This study helps to show how the public will react to different types of news coverage of crises, and subsequently, what the best ways are for corporations to handle any crises they may encounter.
This study was published in Communications Research.
Contact: Nathan Hurst
hurstn@missouri.edu
573-882-6217
University of Missouri-Columbia
Planets around stars are the rule rather than the exception
January 12, 2012
There are more exoplanets further away from their parent stars than originally thought, according to new astrophysics research.
In a new paper appearing in the Jan. 12 edition of the journal, Nature, astrophysicist Kem Cook as part of an international collaboration, analyzed microlensing data that bridges the gap between a recent finding of planets further away from their parent stars and observations of planets extremely close to their parent star. The results point to more planetary systems resembling our solar system rather than being significantly different.
Gravitational microlensing occurs when light from a source star is bent and focused by gravity as a second object (the lens star), which passes between the source star and an observer on Earth. A planet rotating around the lens star will produce an additional deviation in the microlensing. The first gravitational microlensing observations were made by the Massive Astrophysical Compact Halo Object (MACHO) collaboration, led by Livermore scientists.
The new research also determines that a large fraction of planets have orbital distances from 0.5 to 10 sun-Earth distances. In the past, using the Doppler shift technique, most extrasolar planets found were gas giants like Jupiter and Saturn that orbited stars that were much closer to them than the sun is to Earth.
An exoplanet is a planet outside our solar system. Over the past 16 years, astronomers have detected more than 700 confirmed exoplanets and have started to probe the spectra and atmospheres of these worlds. While studying the properties of individual exoplanets is undeniably valuable, a much more basic question remains: how commonplace are planets in the Milky Way?
The team found that approximately 17 percent of stars host Jupiter-mass planets. However, cool-Neptunes and super-Earths are more common, occurring 52 percent and 62 percent, respectively, of the time.
Gravitationally microlensing is very rare. In fact, fewer stars than one per million undergo micolensing at any time.
The team’s result is consistent with every star of the Milky Way, hosting, on average, one planet or more in an orbital distance range of 0.5 to 10 sun-Earth distances.
“Our measurements confirm that low-mass planets are very common and the number of planets increases with decreasing planet mass, in an agreement with the predictions of the core accretion scenario of planet formation,” Cook said. “Planets around stars in our galaxy appear to be the rule rather than the exception.”
“We used to think that the Earth might be unique in our galaxy. But now it seems that there are literally billions of planets with masses similar to Earth orbiting stars in the Milky Way,” concludes Daniel Kuba, of the European Southern Observatory and co-lead author of the paper .
Founded in 1952, Lawrence Livermore National Laboratory (www.llnl.gov) provides solutions to our nation’s most important national security challenges through innovative science, engineering and technology. Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy’s National Nuclear Security Administration.
Contact: Anne Stark
stark8@llnl.gov
925-422-9799
DOE/Lawrence Livermore National Laboratory
Girl power surges in India
January 12, 2012
By putting 18 million cracks in the proverbial glass ceiling, Hillary Clinton changed the way Americans think about women in politics, and new Northwestern University research suggests that an affirmative action law in India is doing the same for Indian women.
The research, to be published Jan. 12 in the journal Science, focused on the long-term outcomes of a law that reserved leadership positions for women in randomly selected village councils in India.
The law has led to a direct role model effect and is changing the way the girls as well as their parents think about female roles of leadership and has improved their attitudes toward higher career aspirations and education goals for women, said Lori Beaman, an assistant professor of economics at the Weinberg College of Arts and Sciences at Northwestern.
Results of the study show that affirmative action laws can help create positive role models by opening opportunities that were previously unavailable to a group.
“India is definitely a place where women are constrained in their opportunities,” said Beaman, who is also a faculty fellow at the Institute for Policy Research at Northwestern and one of the authors of the study. “This law gave Indian women, at the village level, a chance to demonstrate that they are capable leaders.”
Beaman’s research team collected data in West Bengal between 2006 and 2007 on 8,453 male and female teenagers and their parents in 495 villages. The law was implemented in that region starting in 1998 and from that time a village council spot could have been reserved for a female leader once, twice or never.
Here’s a glimpse at how the gender gap narrowed in villages with two terms of female leadership versus the villages that never had a female leader:
- Gender gap in aspirations for their children’s career and education closed by 25 percent in parents
- Gender gap in career and education aspirations closed by 32 percent in adolescents
The decline in the gender gap is entirely driven by an increase in girls’ aspirations, not by a decrease in boys,’ Beaman said.
In a change of behavior, adolescent Indian girls were more likely to be attending school and spent less time on household chores in the villages that reserved political positions for women.
“There weren’t any concurrent changes in education infrastructure or career options for young women during this time,” Beaman said. “The changes in behavior among adolescents can be contributed to the role model effect of the women leaders.”
The randomized process in which the government implemented the policy allowed the researchers to cleanly compare survey results of parents and teens in villages with a female leader for one term and two terms versus parents and teens in villages that had never had a female leader.
The positive effect of the exposure to capable female leaders seemed to mitigate against the perception that the female leaders’ achievements were not due to merit, Beaman said.
The results of this study support the idea that quotas and affirmative action in response to the underrepresentation of women in politics and perhaps in other areas, such as science and the corporate boardroom, is a positive action that creates influential role models and pays off in the long run, Beaman said.
Contact: Erin White
ewhite@northwestern.edu
847-491-4888
Northwestern University
Astronomers reach new frontiers of dark matter
January 9, 2012
For the first time, astronomers have mapped dark matter on the largest scale ever observed. The results, presented by Dr Catherine Heymans of the University of Edinburgh, Scotland, and Associate Professor Ludovic Van Waerbeke of the University of British Columbia, Vancouver, Canada, are being presented today to the American Astronomical Society meeting in Austin, Texas. Their findings reveal a Universe comprised of an intricate cosmic web of dark matter and galaxies spanning more than one billion light years.
An international team of researchers lead by Van Waerbeke and Heymans achieved their results by analysing images of about 10 million galaxies in four different regions of the sky. They studied the distortion of the light emitted from these galaxies, which is bent as it passes massive clumps of dark matter during its journey to Earth.
Their project, known as the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS), uses data from the Canada-France-Hawaii Telescope Legacy Survey. This accumulated images over five years using the wide field imaging camera MegaCam, a 1 degree by 1 degree field-of-view, 340 Megapixel camera on the CFHT in Hawaii.
Galaxies included in the survey are typically six billion light years away. The light captured by the images used in the study was emitted when the Universe was six billion years old – roughly half the age it is today.
The team’s result has been suspected for a long time from studies based on computer simulations, but was difficult to verify owing to the invisible nature of dark matter. This is the first direct glimpse at dark matter on large scales showing the cosmic web in all directions.
Professor Ludovic Van Waerbeke, from the University of British Columbia, said: “It is fascinating to be able to ‘see’ the dark matter using space-time distortion. It gives us privileged access to this mysterious mass in the Universe which cannot be observed otherwise. Knowing how dark matter is distributed is the very first step towards understanding its nature and how it fits within our current knowledge of physics.”
Dr Catherine Heymans, a Lecturer in the University of Edinburgh’s School of Physics and Astronomy, said: “By analysing light from the distant Universe, we can learn about what it has travelled through on its journey to reach us. We hope that by mapping more dark matter than has been studied before, we are a step closer to understanding this material and its relationship with the galaxies in our Universe.”
Dr Christian Veillet, CFHT Executive Director, said “This dark matter study illustrates the strong legacy value of the CFHT Legacy Survey which is now enabling exciting results obtained by teams from many nations which use the images retrieved from the Canadian Astronomy Data Centre where they are archived and publicly available”.
Professor Lance Miller, from Oxford University said: “This result has been achieved through advances in our analysis techniques which we are now applying to data from the Very Large Telescope’s (VLT) Survey Telescope in Chile.”
Professor Koen Kuijken, from Leiden University, said: “Over the next three years we will image more than 10 times the area mapped by CFHTLenS, bringing us ever closer to our goal of understanding the mysterious dark side of the Universe.”
Image Caption: The observations show that dark matter in the Universe is distributed as a network of gigantic dense (white) and empty (dark) regions, where the largest white regions are about the size of an Earth moon on the sky. Credit: Van Waerbeke, Heymans and the CFHTLenS Collaboration
More images are available at:
www.cfhtlens.org
www.cfht.hawaii.edu/en/news/CFHTLens
This research was supported by the European Research Council, Natural Sciences and Engineering Research Council of Canada, the Canadian Institute for Advanced Research and the Canadian Astronomy Data Centre.
Contact: Catriona Kelly
catriona.kelly@ed.ac.uk
44-131-651-4401
University of Edinburgh