Stars found far from galaxy center - Nasa

The newfound young star clusters lie thousands of light-years below the plane of our Milky Way galaxy, a flat spiral disk seen in this artist's conception. If alien lifeforms were to develop on planets orbiting these stars, they would have views of a portion, or all, of the galactic disk. Credit: NASA/JPL-Caltech

Astronomers using data from NASA's Wide-field Infrared Survey Explorer, or WISE, have found a cluster of stars forming at the very edge of our Milky Way galaxy.

"A stellar nursery in what seems to be the middle of nowhere is quite surprising," said Peter Eisenhardt, the project scientist for the WISE mission at NASA's Jet Propulsion Laboratory in Pasadena, California. "But surprises turn up when you look everywhere, as the WISE survey did."
The discovery, led by Denilso Camargo of the Federal University of Rio Grande do Sul in Porto Alegre, Brazil, appears in a new study in the journal Monthly Notices of the Royal Astronomical Society.

The Milky Way, the galaxy we live in, has a barred spiral shape, with arms of stars, gas and dust winding out from a central bar. Viewed from the side, the galaxy would appear relatively flat, with most of the material in a disk and the central regions.

Using infrared survey images from WISE, the team discovered two clusters of stars thousands of light-years below the galactic disk. The stars live in dense clumps of gas called giant molecular clouds.

This is the first time astronomers have found stars being born in such a remote location. Clouds of star-forming material at very high latitudes away from the galactic plane are rare and, in general, are not expected to form stars.

"Our work shows that the space around the galaxy is a lot less empty that we thought," said Camargo. "The new clusters of stars are truly exotic. In a few million years, any inhabitants of planets around the stars will have a grand view of the outside of the Milky Way, something no human being will probably ever experience."

To learn more about the discovery, and what might have caused the stars to form at the edge of our galaxy, read the Royal Astronomical Society news release.

JPL managed and operated WISE for NASA's Science Mission Directorate. The spacecraft was put into hibernation mode in 2011, after it scanned the entire sky twice, completing its main objectives. Edward Wright was the principal investigator and is at UCLA. In September 2013, the WISE spacecraft was reactivated, renamed NEOWISE and assigned a new mission to assist NASA's efforts to identify the population of potentially hazardous near-Earth objects. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena.

The WISE mission was selected competitively under NASA's Explorers Program managed by the agency's Goddard Space Flight Center in Greenbelt, Maryland. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colorado. Caltech manages JPL for NASA.

Source: NASA/Jet Propulsion Laboratory

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Old-looking galaxy in a young universe: Astronomers find dust in the early universe

This spectacular view from the NASA/ESA Hubble Space Telescope shows the rich galaxy cluster Abell 1689. The huge concentration of mass bends light coming from more distant objects and can increase their total apparent brightness and make them visible. One such object, A1689-zD1, is located in the box -- although it is still so faint that it is barely seen in this picture. New observations with ALMA and ESO's VLT have revealed that this object is a dusty galaxy seen when the Universe was just 700 million years old.  Credit: NASA; ESA; L. Bradley (Johns Hopkins University); R. Bouwens (University of California, Santa Cruz); H. Ford (Johns Hopkins University); and G. Illingworth (University of California, Santa Cruz)

Dust plays an extremely important role in the universe -- both in the formation of planets and new stars. But dust was not there from the beginning and the earliest galaxies had no dust, only gas. Now an international team of astronomers, led by researchers from the Niels Bohr Institute, has discovered a dust-filled galaxy from the very early universe. The discovery demonstrates that galaxies were very quickly enriched with dust particles containing elements such as carbon and oxygen, which could form planets. The results are published in the scientific journal, Nature.

Cosmic dust are smoke-like particles made up of either carbon (fine soot) or silicates (fine sand). The dust is comprised primarily of elements such as carbon, silicon, magnesium, iron and oxygen. The elements are synthesised by the nuclear combustion process in stars and driven out into space when the star dies and explodes. In space, they gather in clouds of dust and gas, which form new stars, and for each generation of new stars, more elements are formed. This is a slow process and in the very earliest galaxies in the history of the universe, dust had not yet formed.

But now a team of researchers have discovered a very distant galaxy that contains a large amount of dust, changing astronomers' previous calculations of how quickly the dust was formed.

"It is the first time dust has been discovered in one of the most distant galaxies ever observed -- only 700 million years after the Big Bang. It is a galaxy of modest size and yet it is already full of dust. This is very surprising and it tells us that ordinary galaxies were enriched with heavier elements far faster than expected," explains Darach Watson, an astrophysicist with the Dark Cosmology Centre at the Niels Bohr Institute at the University of Copenhagen.

Darach Watson led the project, with Lise Christensen from the Dark Cosmology Centre and researchers from Sweden, Scotland, France and Italy.

Lucky location

Because the galaxy is very distant and therefore incredibly faint, it would not usually be detectable from Earth. But a fortunate circumstance means the light from it has been amplified. This is because a large cluster of galaxies called Abell 1689, lies between the galaxy and Earth. The light is refracted by the gravity of the galaxy cluster, thus amplifying the distant galaxy. The phenomenon is called gravitational lensing and it works like a magnifying glass.

"We looked for the most distant galaxies in the universe. Based on the colours of the light observed with the Hubble Space Telescope we can see which galaxies could be very distant. Using observations from the very sensitive instrument, the X-shooter spectrograph on the Large Telescope, VLT in Chile, we measured the galaxy's spectrum and from that calculated its redshift, i.e. the change in the light's wavelength as the object recedes from us. From the redshift we can calculate the galaxy's distance from us and it turned out to be, as we suspected, one of the most distant galaxies we know of to date," explains Lise Christensen, an astrophysicist at the Dark Cosmology Centre at the Niels Bohr Institute.

Early planet formation

Darach Watson explains that they then studied the galaxy with the ALMA telescopes, which can observe far-infrared wavelengths and then it became really interesting, because now they could see that the galaxy was full of dust. He explains that young stars in early galaxies emit hot ultraviolet light. The hot ultraviolet radiation heats the surrounding ice-cold dust, which then emits light in the far-infrared.

"It is this far-infrared light, which tells us that there is dust in the galaxy. It is very surprising and it is the first time that dust has been found in such an early galaxy. The process of star formation must therefore have started very early in the history of the universe and be associated with the formation of dust. The detection of large amounts of solid material shows that the galaxy was enriched very early with solids which are a prerequisite for the formation of complex molecules and planets," explains Darach Watson.

Now the researchers hope that future observations of a large number of distant galaxies using the ALMA telescopes could help unravel how frequently such evolved galaxies occur in this very early epoch of the history of the universe.

Source: University of Copenhagen - Niels Bohr Institute

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Newborn neurons in adult brain may help us adapt to environment

Neurons . "New neurons may serve as a means to fine-tune the hippocampus to the predicted environment," Opendak says. "In particular, seeking out rewarding experiences or avoiding stressful experiences may help each individual optimize his or her own brain.
Credit: © ktsdesign / Fotolia
The discovery that the human brain continues to produce new neurons in adulthood challenged a major dogma in the field of neuroscience, but the role of these neurons in behavior and cognition is still not clear. In a review article published by Cell Press February 21st in Trends in Cognitive Sciences, Maya Opendak and Elizabeth Gould of Princeton University synthesize the vast literature on this topic, reviewing environmental factors that influence the birth of new neurons in the adult hippocampus, a region of the brain that plays an important role in memory and learning.

The authors discuss how the birth of such neurons may help animals and humans adapt to their current environment and circumstances in a complex and changing world. They advocate for testing these ideas using naturalistic designs, such as allowing laboratory rodents to live in more natural social burrow settings and observing how circumstances such as social status influence the rate at which new neurons are born.

"New neurons may serve as a means to fine-tune the hippocampus to the predicted environment," Opendak says. "In particular, seeking out rewarding experiences or avoiding stressful experiences may help each individual optimize his or her own brain. However, more naturalistic experimental conditions may be a necessary step toward understanding the adaptive significance of neurons born in the adult brain."

In recent years, it has become increasingly clear that environmental influences have a profound effect on the adult brain in a wide range of mammalian species. Stressful experiences, such as restraint, social defeat, exposure to predator odors, inescapable foot shock, and sleep deprivation, have been shown to decrease the number of new neurons in the hippocampus. By contrast, more rewarding experiences, such as physical exercise and mating, tend to increase the production of new neurons in the hippocampus.

The birth of new neurons in adulthood may have important behavioral and cognitive consequences. Stress-induced suppression of adult neurogenesis has been associated with impaired performance on hippocampus-dependent cognitive tasks, such as spatial navigation learning and object memory. Stressful experiences have also been shown to increase anxiety-like behaviors that are associated with the hippocampus. In contrast, rewarding experiences are associated with reduced anxiety-like behavior and improved performance on cognitive tasks involving the hippocampus.

Although scientists generally agree that our day-to-day actions change our brains even in adulthood, there is some disagreement on the adaptive significance of new neurons. For instance, the literature presents mixed findings on whether new neurons generated under a specific experimental condition are geared toward the recognition of that particular experience or if they provide a more naive pool of new neurons that enable environmental adaptation in the future.

Gould and her collaborators recently proposed that stress-induced decreases in new neuron formation might improve the chances of survival by increasing anxiety and inhibiting exploration, thereby prioritizing safety and avoidant behavior at the expense of performing optimally on cognitive tasks. On the other hand, reward-induced increases in new neuron number may reduce anxiety and facilitate exploration and learning, leading to greater reproductive success.

"Because the past is often the best predictor of the future, a stress-modeled brain may facilitate adaptive responses to life in a stressful environment, whereas a reward-modeled brain may do the same but for life in a low-stress, high-reward environment," says Gould, a professor of psychology and neuroscience at Princeton University.

However, when aversive experiences far outnumber rewarding ones in both quantity and intensity, the system may reach a breaking point and produce a maladaptive outcome. For example, repeated stress produces continued reduction in the birth of new neurons, and ultimately the emergence of heightened anxiety and depressive-like symptoms.

"Such a scenario could represent processes that are engaged under pathological conditions and may be somewhat akin to what humans experience when exposed to repeated traumatic stress," Opendak says.

Because many studies that investigate adult neurogenesis use controlled laboratory conditions, the relevance of the findings to real-world circumstances remains unclear. The use of a visible burrow system--a structure consisting of tubes, chambers, and an open field--has allowed researchers to recreate the conditions that allow for the production of dominance hierarchies that rats naturally form in the wild, replicating the stressors, rewards, and cognitive processes that accompany this social lifestyle.

"This more realistic setting has revealed individual differences in adult neurogenesis, with more new neurons produced in dominant versus subordinate male rats," Gould says. "Taking findings from laboratory animals to the next level by exploring complex social interactions in settings that maximize individual variability, a hallmark of the human experience, is likely to be especially illuminating."

Source: Cell Press

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Is not there Big Bang ? A quantum equation show that the universe has no beginning

The universe could have existed forever, according to a new model that applies quantum correction terms to complement the theory of general relativity of Einstein. The model can also explain dark matter and dark energy.

The widely accepted age of the universe, according to estimates of general relativity, is 13,800 million years. At first, everything was dealt a single infinitely dense point or, in other words, the singularity. After that point began to expand to trigger the Big Bang, considered the origin of the universe, has  Science Direct .

Although the Big Bang singularity arises directly and inevitably mathematics of general relativity, some scientists consider the problematic issue because mathematics can only explain what happened after and not before the singularity .

However, Ahmed Ali Farag, Benha University, Egypt, and Saurya Das University of Lethbridge, Canada, say the Big Bang singularity can be resolved by its new model in which the universe has no beginning nor end .

The researchers used Raychaudhuri equation and the Friedmann equations, which describe the expansion and evolution of the universe (including the Big Bang) in the context of general relativity. The model of Ali and Das contains elements of both quantum theory, of general relativity .

In physical terms, the model describes the universe as full of "quantum fluid" . Scientists propose that this fluid could be composed of gravitons, hypothetical massless particles that mediate the force of gravity.

To understand the origin of the universe, they analyzed the behavior of the fluid over time. Surprisingly, they found that this does not converge towards the singularity, but, on the contrary, the universe seems to have always existed . Although it was smaller in the past, says Das.

Source: RT

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The role of gravitational instabilities in deposition of volcanic ash: The example of Eyjafjallajökull

Figure 1 from Manzella et al.: Original and processed snapshot of the video of the Eyjafjallajökull (Iceland) plume as observed on 4 May 2010. White arrows indicate finger positions. This article is Open Access.

Boulder, Colo., USA – Volcanic ash poses a significant hazard for areas close to volcanoes and for aviation. For example, the 2010 eruption of Eyjafjallajökull, Iceland, clearly demonstrated that even small-to-moderate explosive eruptions, in particular if long-lasting, can paralyze entire sectors of societies, with significant, global-level, economic impacts. In this open-access Geology article, Irene Manzella and colleagues present the first quantitative description of the dynamics of gravitational instabilities and particle aggregation based on the 4 May 2010 eruption.

Their analysis also reveals some important shortcomings in the Volcanic Ash Transport and Dispersal Models (VATDMs) typically used to forecast the dispersal of volcanic ash. In particular, specific processes exist that challenge the view of sedimentation of fine particles from volcanic plumes and that are currently poorly understood: particle aggregation and gravitational instabilities. These appear as particle-rich "fingers" descending from the base of volcanic clouds and have commonly been observed during volcanic explosive eruptions.

Based on direct observations of the 2010 Eyjafjallajökull plume, on the correlation with the associated fallout deposit, and on dedicated laboratory analogue experiments, Irene Manzella and colleagues show how fine ash in these particle-rich fingers settles faster than individual particles and that aggregation and gravitational instabilities are closely related. Both phenomena can significantly contribute to reducing fine-ash lifetime in the atmosphere and, therefore, it is crucial to include them in VATDMs in order to provide accurate forecasting of ash dispersal and sedimentation.

Source: Gsa

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Drilling Reveals Fault Rock Architecture in New Zealand’s Central Alpine Fault

            Figure 1: Location map of study by Virginia Toy et al. Image Credit: GSA
Boulder, Colo., USA - Rocks within plate boundary scale fault zones become fragmented and altered over the earthquake cycle. They both record and influence the earthquake process. In this new open-access study published in Lithosphere on 4 Feb., Virginia Toy and colleagues document fault rocks surrounding New Zealand's active Alpine Fault, which has very high probability of generating a magnitude 8 or greater earthquake in the near future.

Descriptions already suggest that the complex fault rock sequence results from slip at varying rates during multiple past earthquakes, and even sometimes during aseismic slip. They also characterize this fault before rupture; Toy and colleagues anticipate that repeat observations after the next event will provide a previously undescribed link between changes in fault rocks and the ground shaking response. They write that in the future this sort of data might allow realistic ground shaking predictions based on observations of other "dormant" faults.

The first phase of the Deep Fault Drilling Project (DFDP-1) yielded a continuous lithological transect through fault rock surrounding the Alpine fault (South Island, New Zealand). This allowed micrometer- to decimeter-scale variations in fault rock lithology and structure to be delineated on either side of two principal slip zones intersected by DFDP-1A and DFDP-1B. Here, we provide a comprehensive analysis of fault rock lithologies within 70 m of the Alpine fault based on analysis of hand specimens and detailed petrographic and petrologic analysis. The sequence of fault rock lithologies is consistent with that inferred previously from outcrop observations, but the continuous section afforded by DFDP-1 permits new insight into the spatial and genetic relationships between different lithologies and structures. We identify principal slip zone gouge, and cataclasite-series rocks, formed by multiple increments of shear deformation at up to coseismic slip rates. A 20−30-m-thick package of these rocks (including the principal slip zone) forms the fault core, which has accommodated most of the brittle shear displacement. 

This deformation has overprinted ultramylonites deformed mostly by grain-size-insensitive dislocation creep. Outside the fault core, ultramylonites contain low-displacement brittle fractures that are part of the fault damage zone. Fault rocks presently found in the hanging wall of the Alpine fault are inferred to have been derived from protoliths on both sides of the present-day principal slip zone, specifically the hanging-wall Alpine Schist and footwall Greenland Group. This implies that, at seismogenic depths, the Alpine fault is either a single zone of focused brittle shear that moves laterally over time, or it consists of multiple strands. Ultramylonites, cataclasites, and fault gouge represent distinct zones into which deformation has localized, but within the brittle regime, particularly, it is not clear whether this localization accompanies reductions in pressure and temperature during exhumation or whether it occurs throughout the seismogenic regime. These two contrasting possibilities should be a focus of future studies of fault zone architecture.

Source:GSA

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What is the Benefits of ISS Research - A interview Video

Earth framing the International Space Station

Earth framing the International Space Station in May 2010 following undocking of Atlantis during the STS-132 mission. (NASA)

Almost as soon as the International Space Station was habitable, researchers began using it to study the impact of microgravity and other space effects on several aspects of our daily lives. This unique scientific platform continues to enable researchers from all over the world to put their talents to work on innovative experiments that could not be done anywhere else. 

Although each space station partner has distinct agency goals for station research, each partner shares a unified goal to extend the resulting knowledge for the betterment of humanity. We may not know yet what will be the most important discovery gained from the space station, but we already have some amazing breakthroughs! In the areas of human health, telemedicine, education and observations of Earth from space, there are already demonstrated benefits to human life. Vaccine development research, station-generated images that assist with disaster relief and farming, and education programs that inspire future scientists, engineers and space explorers are just some examples of research benefits. 

The stories featured here summarize the scientific, technological and educational accomplishments of research on the space station that has and will continue to have an impact on life on Earth.

The benefits outlined here serve as examples of the space station's potential as a groundbreaking scientific research facility. Through advancing the state of scientific knowledge of our planet, looking after our health, and providing a space platform that inspires and educates the science and technology leaders of tomorrow, these benefits will drive the legacy of the space station as its research strengthens economies and enhances the quality of life here on Earth for all people.

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Source: Nasa

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NASA Launches Groundbreaking Soil Moisture Mapper

NASA's Soil Moisture Active Passive (SMAP) observatory lifts off from Space Launch Complex 2 West at California's Vandenberg Air Force Base, beginning a three-year mission to map Earth's vital moisture hidden in the soils beneath our feet. Image credit: NASA/Bill Ingalls

NASA successfully launched its first Earth satellite designed to collect global observations of the vital soil moisture hidden just beneath our feet.

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The Soil Moisture Active Passive (SMAP) observatory, a mission with broad applications for science and society, lifted off at 6:22 a.m. PST (9:22 a.m. EST) Saturday from Vandenberg Air Force Base, California, on a United Launch Alliance Delta II rocket. NASA's Jet Propulsion Laboratory in Pasadena, California, manages SMAP for NASA's Science Mission Directorate in Washington, with instrument hardware and science contributions made by NASA's Goddard Space Flight Center in Greenbelt, Maryland.

About 57 minutes after liftoff, SMAP separated from the rocket's second stage into an initial 411- by 425-mile (661- by 685-kilometer) orbit. After a series of activation procedures, the spacecraft established communications with ground controllers and deployed its solar array. Initial telemetry shows the spacecraft is in excellent health.
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SMAP now begins a three-year mission that will figuratively scratch below Earth's surface to expand our understanding of a key component of the Earth system that links the water, energy and carbon cycles driving our living planet. SMAP's combined radar and radiometer instruments will peer into the top 2 inches (5 centimeters) of soil, through clouds and moderate vegetation cover, day and night, to produce the highest-resolution, most accurate soil moisture maps ever obtained from space.

The mission will help improve climate and weather forecasts and allow scientists to monitor droughts and better predict flooding caused by severe rainfall or snowmelt -- information that can save lives and property. In addition, since plant growth depends on the amount of water in the soil, SMAP data will allow nations to better forecast crop yields and assist in global famine early-warning systems.

"The launch of SMAP completes an ambitious 11-month period for NASA that has seen the launch of five new Earth-observing space missions to help us better understand our changing planet," said NASA Administrator Charles Bolden. "Scientists and policymakers will use SMAP data to track water movement around our planet and make more informed decisions in critical areas like agriculture and water resources."

SMAP also will detect whether the ground is frozen or thawed. Detecting variations in the timing of spring thaw and changes in the length of the growing season will help scientists more accurately account for how much carbon plants are removing from Earth's atmosphere each year.

"The next few years will be especially exciting for Earth science thanks to measurements from SMAP and our other new missions," said Michael Freilich, director of the Earth Science Division of NASA's Science Mission Directorate in Washington. "Each mission measures key variables that affect Earth's environment. SMAP will provide new insights into the global water, energy and carbon cycles. Combining data from all our orbiting missions will give us a much better understanding of how the Earth system works."

SMAP will orbit Earth from pole to pole every 98.5 minutes, repeating the same ground track every eight days. Its 620-mile (1,000-kilometer) measurement swath allows SMAP to cover Earth's entire equatorial regions every three days and higher latitudes every two days. The mission will map global soil moisture with about 5.6-mile (9-kilometer) resolution.

"SMAP will improve the daily lives of people around the world," said Simon Yueh, SMAP project scientist at JPL. "Soil moisture data from SMAP has the potential to significantly improve the accuracy of short-term weather forecasts and reduce the uncertainty of long-term projections of how climate change will impact Earth's water cycle."

The SMAP team is engaged with many organizations and individuals that see immediate uses for the satellite's data. Through workshops and tutorials, the SMAP Applications Working Group is collaborating with 45 "early adopters" to test and integrate the mission's data products into many different applications. Early adopters include weather forecasters from several nations, as well as researchers and planners from the U.S. Department of Agriculture, U.S. Geological Survey, U.S. Centers for Disease Control and Prevention, and the United Nations World Food Programme.

During the next 90 days, SMAP and its ground system will be commissioned to ensure they are fully functional and are ready to begin routine science data collection. A key milestone will be the deployment of the spacecraft's instrument boom and 20-foot-diameter (6-meter) reflector antenna. The observatory will be maneuvered to its final 426-mile (685-kilometer), near-polar operational orbit, and the antenna will spin up to 14.6 revolutions per minute.

SMAP science operations will then begin, and SMAP data will be calibrated and validated. The first release of SMAP soil moisture data products is expected within nine months. Fully validated science data are expected to be released within 15 months.

SMAP's Delta II rocket also carried a JPL CubeSat into orbit. The GRIFEX (Geostationary Coastal and Air Pollution Events Read-Out Integrated Circuit In-Flight Performance Experiment) CubeSat was one of three NASA-sponsored CubeSat missions successfully deployed during the launch. About the size of a loaf of bread, GRIFEX will validate cutting-edge detector technology for use in future Earth-observing satellites.

JPL built the SMAP spacecraft and is responsible for project management, system engineering, radar instrumentation, mission operations and the ground data system. Goddard is responsible for the radiometer instrument and science data products. Both centers collaborate on science data processing and delivery to the Alaska Satellite Facility, in Fairbanks, and the National Snow and Ice Data Center at the University of Colorado in Boulder. NASA's Launch Services Program at the agency's Kennedy Space Center in Florida was responsible for launch management. JPL is managed for NASA by the California Institute of Technology in Pasadena.

Source: Nasa

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How to Learn math without fear, Stanford expert says

Stanford Prof. Boaler finds that children who excel in math learn to develop "number sense," which is much different from the memorization that is often stressed in school.
Image Credit: THEPLANETWALL STOCK

Students learn math best when they approach the subject as something they enjoy, according to a Stanford education expert. Speed pressure, timed testing and blind memorization pose high hurdles in the youthful pursuit of math.

"There is a common and damaging misconception in mathematics – the idea that strong math students are fast math students," said Jo Boaler, a Stanford professor of mathematics education and the lead author on a new working paper. Boaler's co-authors are Cathy Williams, cofounder of Stanford'sYouCubed, and Amanda Confer, a Stanford graduate student in education. 

Curriculum timely

Fortunately, said Boaler, the new national curriculum standards known as the Common Core Standards for K-12 schools de-emphasize the rote memorization of math facts. Maths facts are fundamental assumptions about math, such as the times tables (2 x 2 = 4), for example. Still, the expectation of rote memorization continues in classrooms and households across the United States.

While research shows that knowledge of math facts is important, Boaler said the best way for students to know math facts is by using them regularly and developing understanding of numerical relations. Memorization, speed and test pressure can be damaging, she added.

On the other hand, people with "number sense" are those who can use numbers flexibly, she said. For example, when asked to solve the problem of 7 x 8, someone with number sense may have memorized 56, but they would also be able to use a strategy such as working out 10 x 7 and subtracting two 7s (70-14).

"They would not have to rely on a distant memory," Boaler wrote.

In fact, in one research project the investigators found that the high-achieving students actually used number sense, rather than rote memory, and the low-achieving students did not.

The conclusion was that the low achievers are often low achievers not because they know less but because they don't use numbers flexibly.

"They have been set on the wrong path, often from an early age, of trying to memorize methods instead of interacting with numbers flexibly," she wrote. Number sense is the foundation for all higher-level mathematics, she noted. 

Role of the brain

Boaler said that some students will be slower when memorizing, but still possess exceptional mathematics potential.

"Math facts are a very small part of mathematics, but unfortunately students who don't memorize math facts well often come to believe that they can never be successful with math and turn away from the subject," she said.

Prior research found that students who memorized more easily were not higher achieving – in fact, they did not have what the researchers described as more "math ability" or higher IQ scores. Using an MRI scanner, the only brain differences the researchers found were in a brain region called the hippocampus, which is the area in the brain responsible for memorizing facts – the working memory section.

But according to Boaler, when students are stressed – such as when they are solving math questions under time pressure – the working memory becomes blocked and the students cannot as easily recall the math facts they had previously studied. This particularly occurs among higher achieving students and female students, she said.

Some estimates suggest that at least a third of students experience extreme stress or "math anxiety" when they take a timed test, no matter their level of achievement. "When we put students through this anxiety-provoking experience, we lose students from mathematics," she said.

Boaler contrasts the common approach to teaching math with that of teaching English. In English, a student reads and understands novels or poetry, without needing to memorize the meanings of words through testing. They learn words by using them in many different situations – talking, reading and writing.

"No English student would say or think that learning about English is about the fast memorization and fast recall of words," she added.

Strategies, activities 

In her paper, "Fluency without Fear," Boaler provides activities for teachers and parents that help students learn math facts at the same time as developing number sense. These include number talks, addition and multiplication activities, and math cards.

Importantly, she said, these activities include a focus on the visual representation of number facts. When students connect visual and symbolic representations of numbers, they are using different pathways in the brain, which deepens their learning, as shown by recent brain research.

"Math fluency" is often misinterpreted, with an over-emphasis on speed and memorization, she said. "I work with a lot of mathematicians, and one thing I notice about them is that they are not particularly fast with numbers; in fact some of them are rather slow. This is not a bad thing; they are slow because they think deeply and carefully about mathematics."

She refers to the famous French mathematician, Laurent Schwartz, who wrote in his autobiography that he often felt stupid in school, as he was one of the slowest math thinkers in class.
Math anxiety and fear play a big role in students dropping out of mathematics, said Boaler.

"When we emphasize memorization and testing in the name of fluency we are harming children, we are risking the future of our ever-quantitative society and we are threatening the discipline of mathematics. We have the research knowledge we need to change this and to enable all children to be powerful mathematics learners. Now is the time to use it," she said.

Source: Standford Unversity

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HIV testing yields diagnoses in Kenya but few seek care

A sweeping effort in a rural region of Kenya to test all adults for HIV discovered 1,300 new infections, but few of the newly diagnosed people pursued treatment, a study in the journal Lancet HIV reports.
PROVIDENCE, R.I. [Brown University] — Between December 2009 and February 2011, health workers with the AMPATH Consortium sought to test and counsel every adult resident in the Bunyala subcounty of Kenya for HIV. A study in the journal Lancet HIV reports that the campaign yielded more than 1,300 new positive diagnoses, but few of those new patients sought health care.

“Home-based counseling and testing (HBCT) provided a diagnosis to nearly 40 percent of people living with HIV in this subcounty who otherwise most likely would not have gone for HIV testing,” said study lead author Becky Genberg, assistant professor (research) of health services, policy and practice in the Brown University School of Public Health. “They therefore would not have known about their HIV infection and not had the opportunity to change their behavior to protect others.”

AMPATH’s HBCT program is part of a strategy to identify all individuals living with HIV in the catchment area, start them on antiretroviral medication as soon as possible, and help them stay on their medications. Antiretroviral medication not only suppresses HIV infections for most patients but also reduces their ability to transmit the virus.

Genberg with co-author Edwin Sang “We are working on a variety of studies, all designed to understand the barriers facing the newly diagnosed, and to implement and evaluate strategies to increase their engagement and retention in HIV care over time.”

In Bunyala, home to about 66,000 people, the HBCT program tested about 32,000 adults. Among them, 3,482 had HIV. Of those, 2,122 already knew they were infected, but 1,360 did not know it yet.

A major finding of the study is that three years later only 15 percent of the newly diagnosed people had engaged in care for their infection. A likely reason why, Genberg said, is that newly diagnosed people typically don’t yet feel sick.

“That so few linked to care following HBCT is a call for innovative and creative strategies to work alongside HBCT to support the mostly healthy, asymptomatic newly diagnosed to engage with care in a way that is meaningful for them,” Genberg said.

In an editorial in the journal, Rashida Ferrand of the London School of Hygiene and Tropical Medicine said the study sounds a warning that home-based testing must be paired with effective ways to convince newly diagnosed patients to seek help.

“Unless paired with interventions targeted at hard-to-reach populations, the diagnosing of undiagnosed individuals in many settings will not be cost-effective and will have little effect on individual and population viral suppression,” she and colleagues wrote.

Genberg, who has been in Kenya this winter, said she is working with Kenyan collaborators on developing the needed interventions: “Right now we are working on a variety of studies, all designed to understand the barriers facing the newly diagnosed, and to implement and evaluate strategies to increase their engagement and retention in HIV care over time.”

In addition to Genberg the study’s authors are Joseph Hogan and Corey Duefield of Brown; Violet Naanyu, Juddy Wachira, and Samson Ndege of Moi University in Kenya; Edwin Sang, Monicah Nyambura, and Michael Odawa of AMPATH; and corresponding author Paula Braitstein of the University of Toronto.

The President’s Emergency Plan for AIDS Relief funded the study though USAID (grant AID-623-A-12-0001). Additional support came from the National Institutes of Health (K01MH099966) and the Bill and Melinda Gates Foundation.

Source: Brown University

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Gully patterns document Martian climate cycles

Martian gullies, old and new Sharp-featured, relatively recent gullies (blue arrows) and degraded older gullies (gold) in the same location on the surface of Mars suggest multiple episodes of liquid water flow, consistent with cyclical climate change on the Red Planet. Image: NASA HiRISE

Gullies carved into impact craters on Mars provide a window into climate change on the Red Planet. A new analysis suggests Mars has undergone several ice ages in the last several million years. The driver of these climate swings is likely the Red Planet's wobbly axis tilt.

PROVIDENCE, R.I. [Brown University] — Geologists from Brown University have found new evidence that glacier-like ice deposits advanced and retreated multiple times in the midlatitude regions of Mars in the relatively recent past.

For the study, in press in the journal Icarus, the researchers looked at hundreds of gully-like features found on the walls of impact craters throughout the Martian midlatitudes. They conclude that many of those gullies were formed by meltwater from icy deposits, which are known to have covered the Martian midlatitudes within the last 2 million years. The study also turned up evidence of multiple gully-forming events, suggesting that these ice deposits waxed and waned several times over the last several million years — relatively recently in Mars’ 4.5-billion year history.

“These recent climate cycles have been predicted by computer models, but have not been documented with widespread geological evidence until now,” said Jay Dickson, a researcher at Brown and the study’s lead author. “This research shows that gullies have been episodic across the entire southern hemisphere, a distribution that is required for this to be a signal of global climate change.”

Wobbly axis

At present, most of the water ice on Mars is concentrated at its poles, but there’s a wealth of evidence that it wasn’t always that way. In 2003, research led by Brown geologists James Head and Jack Mustard showed that the midlatitude regions of Mars are draped to varying degrees by layers of ice-rich soil and dust. Landforms in and around the deposits, termed the “latitude-dependent mantle,” look remarkably similar to glacial terrains found here on Earth. The deposits suggest the presence of thin glacier-like ice deposits sometime between 400,000 and 2 million years ago.

The researchers concluded that this recent Martian ice age was likely linked to the planet’s wobbly rotation around its axis. Currently, the angle of Mars’ axis — its obliquity — is about 25 degrees, fairly close to that of Earth. But because Mars lacks a large moon to stabilize its rotation, its recent obliquity oscillates between around 15 degrees and as much as 35 degrees. (Earth’s obliquity, in contrast, varies only 2.4 degrees). Computer models predict that when the obliquity of Mars exceeds 30 degrees, increased sunlight at the poles causes water in the ice caps to be freed into the atmosphere. That water is transported and deposited closer to the equator in the form of glacial snow and ice.

Mars is known to have crossed the 30-degree threshold in obliquity several times during the last 20 million years. So if obliquity drives ice ages, there should be evidence for multiple glacial periods in the Martian midlatitudes, and that’s what the researchers were looking for in this latest study.

Gullies old and new

The researchers looked at detailed images taken by NASA’s High Resolution Imaging Science Experiment (HiRISE) of 479 gullies in the midlatitudes of Mars’ southern hemisphere. The gully systems, which form on steep crater walls, consist of an alcove at the top from which sediment is excavated, a channel through which material is carried, and a delta-like fan at the bottom where material is deposited.

The survey showed gully systems in various states of erosion and degradation. In some places, older gully fans, eroded over many years by the elements, had been crosscut by new gully fan systems. That suggests at least two gully-carving events. In other examples, gully fans were clearly visible, but the alcoves and channels that supplied them had disappeared, covered by a new layer of ice-rich soil. That too suggests multiple periods of glacial deposition.

“We show solid evidence of at least two periods of emplacement of the latitude-dependent mantle,” said Head, an author on the new paper. “That’s consistent with the idea of cyclical ice ages on Mars related to its obliquity.”

The work also bolsters the idea the many of gullies were carved by flows of liquid water. In recent years researchers have shown that some of these gully systems are still active today, when the flow of liquid water is unlikely. The present-day activity is likely driven by CO2 frost, which evaporates from the soil causing rock and rubble to slide down slopes. But this latest study shows that gullies were active when obliquity was higher and CO2 frost would have been sparse. And the association of gullies with ice-rich deposits strongly suggests that water carved these older gullies.

“We see similar features in Antarctica,” Head said. “Despite cold air temperatures, the sun is able to heat ice just enough for melting and gully activity to occur.”

This and other research pointing to relatively recent ice ages on Mars suggest the midlatitudes of Mars could be a place to look for signs of past life, Head said.

“I think people have this idea of Mars as an inactive place, that it is now as it has been for billions of years,” he said. “But it seems likely that climate cycles and global climate change are still occurring.”

Source: Brown University

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Study Yields Surprising Insights into Global Effects of Wood Fuel Burning

Courtesy of Adrian Ghilardi

The harvesting of wood to meet the heating and cooking demands for billions of people worldwide has less of an impact on global forest loss and carbon dioxide (CO2) emissions than previously believed, according to a new Yale-led study.

Writing in the journal Nature Climate Change, a team of researchers, including Prof. Robert Bailis of the Yale School of Forestry & Environmental Studies (F&ES), concludes that only about 27 to 34 percent of wood fuel harvested worldwide would be considered “unsustainable.” According to the assessment, “sustainability” is based on whether or not annual harvesting exceeds incremental re-growth.

The other authors are Rudi Drigo, an independent forestry specialist with international experience; and Adrian Ghilardi and Omar Masera of the National Autonomous University of Mexico.

According to the authors, the findings point to the need for more nuanced, local-specific policies that address forest loss, climate change, and public health. They also suggest that existing carbon offset methodologies used to reduce carbon emissions likely overstate the CO2 emission reductions that can be achieved through the promotion of more efficient cookstove technologies.

The study identifies a set of “hotspots” where the majority of wood extraction exceeds sustainable yields. These hotspot regions — located mainly in South Asia and East Africa — support about 275 million people who are reliant on wood fuel.

“If forests and woodlands would have been cut down anyway, then the projects designed to reduce wood fuel demand are not actually going to reduce deforestation.”— Robert Bailis

However, in other regions, the authors say, much of the wood used for this traditional heating and cooking is actually the byproduct of deforestation driven by other factors, such as demand for agricultural land, which would have occurred anyway.

“If forests and woodlands would have been cut down anyway, then the projects designed to reduce wood fuel demand are not actually going to reduce deforestation,” said Bailis, an associate professor at F&ES and lead author of the study. “Sure, you’re reducing wood use, but the underlying pressures driving deforestation are still out there.”

The results stand in contrast to a long-held assumption that the harvesting of wood fuels — which accounts for more than half of the wood harvested worldwide — is a major driver of deforestation and climate change.
  
Using a model originally developed by Drigo and Masera, and already applied in more than 20 countries, the researchers produce a spatially explicit snapshot of wood fuel supply and demand in 90 countries across the world’s tropical regions, where burning wood is a critical source of energy for cooking and heating.

“One of the problems with traditional bio-energy is that the situation is very locally specific, so you can’t come up with a general response for all places,” said Masera. “One of the real strengths of this paper is that it demonstrates a methodology that allows you to identify priority regions for intervention”

The study identified a set of “hotspot” regions in South Asia and Eastern Africa where the majority of wood extraction exceeds sustainable yields.

In addition to the global analysis, the researchers are using the same model to evaluate the sustainability of wood fuel resources in three case studies: Honduras, Kenya, and the Indian state of Karnataka.

“Even within a given country the situation varies a great deal,” said Drigo. “Some areas are over-exploited while others are under-exploited or totally untouched. A better understanding of the relationship between supply and demand requires this type of spatial approach to clarify what the impacts of different policies will be.”

Emissions from wood fuels account for about 1.9 to 2.3 percent of global emissions, the study says. The deployment of 100 million improved cookstoves could reduce this by 11 to 17 percent, said Bailis, who also studies the factors that influence the adoption of cleaner cookstoves in developing nations.

These reductions would be worth more than $1 billion per year in avoided greenhouse gas emissions if black carbon were integrated into carbon markets, he said.

“We need to be able to understand where these different components of non-renewability are coming from in order to get a better sense of the positive impacts of putting stoves into peoples' homes or promoting transitions to cooking with gas or electricity,” he said.

The research was funded by the Global Alliance for Clean Cookstoves, an initiative supported by the UN Foundation.

Source: Yale University

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New Zealand leads research on natural quit smoking remedy

New Zealand researchers have found that a low cost, plant-based product marketed for smoking cessation in parts of Europe for the last 40 years, is better than nicotine replacement therapy at helping smokers quit. 

Trial results show that the compound cytisine is more effective than nicotine replacement therapy (NRT) at helping smokers quit.

The trial is the first of its kind in the world and was carried out by the National Institute for Health Innovation at the University of Auckland.  The study results were published recently in the top-rated international medical journal, the New England Medical Journal.

Cytisine is a natural, plant-based compound that has been used in smoking cessation for more than 40 years in Eastern Europe and is commercially produced in Bulgaria and Poland.  The trial followed 1310 adult daily smokers who called the national Quitline in New Zealand.

 Smokers were randomly assigned to receive either cytisine for 25 days or eight weeks of NRT. Participants in both groups also received telephone-based Quitline behavioural support.

Results indicated that after using cytisine for 25 days, a smoker was more likely to have quit smoking at six months, compared to using NRT. Compared to NRT, cytisine users experienced a slight increase in side effects; the most common of which were nausea, vomiting and sleep disturbances.

 “Placebo-controlled trials showed that cytisine almost doubles the chances of still being smoke-free at six months,” says study senior author, Dr Natalie Walker, who is the Heart Foundation Douglas Senior Research Fellow (Prevention) at the University of Auckland’s National Institute for Health Innovation. “We wanted to see how effective cytisine was compared to NRT at helping smokers quit.”

 In New Zealand and many other Western countries NRT is the most common medication used to support people to quit smoking.

 Cytisine is an alkaloid which naturally occurs in the Golden Rain (Laburnum anagyroides) and other members of the Fabaceae plant family.

“To the brain cytisine looks a little like nicotine and so it works to alleviate any urges to smoke and reduces the severity of nicotine withdrawal symptoms.  Plus, if you do smoke whilst using cytisine it will be less satisfying - making quitting easier”, says Dr Walker.

Cytisine is a similar type of drug to varenicline (the most effective smoking cessation treatment available, marketed by Pfizer), but is substantially cheaper (cytisine: US$20-$30 for 25-days, NRT: US$112-$685 for 8-10 weeks, varenicline: US$474-501 for 12 weeks).

“There is a big opportunity for low and middle income countries to access a low priced quit remedy,” says Dr Walker. “It’s great for countries that cannot afford more expensive smoking cessation medicines.”

Cytisine is licensed for use as an ‘over the counter’ medication, on prescription or via the internet in a number of Central and Eastern European countries, but it is not yet available in New Zealand.  

“Internationally, very few researchers are undertaking research on the use of cytisine for smoking cessation,” says Associate Professor Chris Bullen, Director of the National Institute for Health Innovation.

“Researchers at the University of Auckland are leading the way.  For example, other researchers in the Department of Pharmacology and at the School of Pharmacy are looking at how cytisine is absorbed and metabolised by the body,” he says.

The trial is funded by the Health Research Council of New Zealand and is one of a number of studies the Institute have undertaken to find innovative options for smokers to stop smoking to achieve smoke-free New Zealand by 2025.  The last trial they completed was one involving e-cigarettes

The study, ‘Randomized comparison of cytisine versus nicotine for smoking cessation’, by Dr Natalie Walker (National Institute for Health Innovation, University of Auckland), Dr Colin Howe (NIHI), Dr Marewa Glover (Centre for Tobacco Control Research, UoA), Dr Hayden McRobbie (Queen Mary University London), Associate Professor Jo Barnes (School of Pharmacy, UoA), Dr Vili Nosa (UoA), Ms Varsha Parag (NIHI), Mr Bruce Bassett (Quit Group), Associate Professor Chris Bullen (Director, NIHI).

Source: Auckland University

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New Weight Loss Device Makes You Feel Full

People who are obese have a new tool in their arsenal for fighting excess weight.

The U.S. Food and Drug Administration approved a medical device called the Maestro Rechargeable System that is implanted in the stomach and, through an external, adjustable controller, helps obese people lose weight. It is approved for patients 18 and older who have a body mass index of 35 to 45, have a condition related to being obese such as type 2 diabetes, and have not been able to lose weight through traditional means. 

The Maestro Rechargeable System targets nerve pathways between the brain and the stomach that are responsible for making a person feel full. In a clinical trial, patients using the device lost 8.5% more weight than people who received an inactive version of it. About 53% of the patients with the device lost at least 20% of their excess weight, and 38% lost at least 25%.

But compared with bariatric surgery, the trial’s results are not as impressive. Eric T. Volckmann, M.D., who specializes in bariatric surgery at University of Utah Health Care, says that after gastric bypass surgery, patients can expect to lose 60% to 80% of their excess body weight.

Bariatric surgery is a highly invasive procedure. But so is implantation of the Maestro Rechargeable System. 

“Any procedure, no matter how small, is still risky,” Volckmann says.

Furthermore, Volckmann says the long-term effects of the device are not as well understood as those of bariatric surgery. He says more research is needed before he would recommend the Maestro Rechargeable System for a severely obese patient.

In the future, the device may make sense for a patient with a BMI between 30 and 35 who is not responding to medical weight loss measures such as lifestyle modifications.

Source: University of Utah

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The state of astronomy before Hubble and the difficulties of observing from the ground that drove the need for a space telescope' Videos

This video looks at the state of astronomy before Hubble and the difficulties of observing from the ground that drove the need for a space telescope. Image Credit: Space Telescope Science Institute

Dr. Nancy Grace Roman, first chief astronomer at NASA’s then Office of Space Science and the one who set up NASA’s astronomy program in the 1960s, speaks about the importance of building and launching a space telescope instead of building duplicates of the Earth-based Palomar 200-inch telescope.

"Astronomers have wanted for generations actually to get a telescope above the atmosphere,” Roman said. “I like to describe the atmosphere being something like looking through an old stained glass window… The glass has defects in it and that sort of keeps you from getting a sharp picture and the atmosphere also has defects." 

"The very sharp images it would produce would allow you to see things that were much fainter than would ever be possible from the ground," said C. Robert O'Dell, of Vanderbilt University in Nashville, Tennessee. O'Dell leads a research team that used Hubble and several ground-based telescopes to obtain the best view yet of the iconic Ring Nebula.
The video addresses several challenges at the time of Hubble's creation, including digital imaging at a time when the industry was in its infancy. The video also speaks on how the telescope has far exceeded its initial life-span.

The 4 minute and 23 second video was produced by STScI. The "Hubble 25th Anniversary" video series is available in HQ, large and small Quicktime formats, HD, large and small WMV formats, and HD, large and small Xvid formats.

WATCH VIDEO HERE



Source: Nasa Hubble

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