#Earth s inner core spins faster than rest of planet University of Leeds rightoriginal Studyposted by Ben Jones-U. Leeds on September 17 2013the Earth s
inner core made up of solid iron uperrotatesin an eastward direction while the outer core comprising mainly molten iron spins westwards at a slower pace.
Although Edmund Halley who also discovered the famous comet showed the westward-drifting motion of the Earth s geomagnetic field in 1692 it is the first time that scientists have been able to link the way the inner core spins to the behavior of the outer core.
The planet behaves in this way because it is responding to the Earth s geomagnetic field.
The findings published in the Proceedings of the National Academy of Sciences help scientists to interpret the dynamics of the core of the Earth the source of our planet s magnetic field.
In the last few decades seismometers measuring earthquakes travelling through the Earth s core have identified an eastwards
or superrotation of the solid inner core relative to Earth s surface. he link is explained simply in terms of equal and opposite actionsays Philip Livermore of the School of Earth
and Environment at the University of Leeds. he magnetic field pushes eastwards on the inner core causing it to spin faster than the Earth
but it also pushes in the opposite direction in the liquid outer core which creates a westward motion. he solid iron inner core is about the size of the Moon.
It is surrounded by the liquid outer core an iron alloy whose convection-driven movement generates the geomagnetic field.
The fact that the Earth s internal magnetic field changes slowly over a timescale of decades means that the electromagnetic force responsible for pushing the inner and outer cores will itself change over time.
This may explain fluctuations in the predominantly eastwards rotation of the inner core a phenomenon reported for the last 50 years by Tkalä iä#et al. in a recent study published in Nature Geoscience.
Viewed within the conclusions of the new model this suggests that the inner core may have undergone a westwards rotation in such periods.
The authors used a model of the Earth s core that was run on the giant supercomputer Monte Rosa part of The swiss National Supercomputing Centre in Lugano Switzerland.
Using a new method they were able to simulate the Earth s core with an accuracy about 100 times better than other models.
The study was a collaboration between the University of Leeds and The swiss Federal Institute of technology Zurich.
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#Ink-jet printing creates soft nanostructures A new way to make nanostructures combines advanced ink-jet printing technology with block copolymers that spontaneously form ultra-fine structures.
The new approach could have applications for the semiconductor and magnetic storage industries. Researchers were able to increase the resolution of their intricate structure fabrication from approximately 200 nanometers to approximately 15 nanometers.
A nanometer is a billionth of a meter the width of a double-stranded DNA molecule.
The ability to fabricate nanostructures out of polymers DNA proteins and other oftmaterials has the potential to enable new classes of electronics diagnostic devices and chemical sensors.
The challenge is that many of these materials are fundamentally incompatible with the sorts of lithographic techniques that are used traditionally in the integrated circuit industry.
Recently developed ultra high-resolution ink jet printing techniques have some potential with demonstrated resolution down to 100-200 nanometers
but there are significant challenges in achieving true nanoscale dimension. ur work demonstrates that processes of polymer self-assembly can provide a way around this limitationsays John Rogers professor of materials science and engineering at University of Illinois at Urbana-Champaign.
Combining jet printing with self-assembling block copolymers enabled the engineers to attain the much higher resolution as suggested by lead author Serdar Onses a postdoctoral scientist at Illinois. Onses earned his doctorate at the University of Wisconsin
under Paul Nealey now professor of molecular engineering at the University of Chicago and a co-author of the paper in Nature Nanotechnology. his concept turned out to be really usefulrogers says.
Engineers use self-assembling materials to augment traditional photolithographic processes that generate patterns for many technological applications.
They first create either a topographical or chemical pattern using traditional processes. For the new paper this was done at imec in Belgium an independent nanoelectronics research center.
The resolution of the chemical pattern nears the current limit of traditional photolithography notes Lance Williamson a graduate student in molecular engineering at University of Chicago
and co-author of the article. mec has the capability to perform the photolithography at this scale over large areas with high precisionwilliamson says.
Back at the University of Illinois engineers place a block copolymer atop this pattern. The block copolymer self-organizes directed by the underlying template to form patterns that are at much higher resolution than the template itself.
Previous work has focused on the deposition and assembly of uniform films on each wafer or substrate resulting in patterns with essentially only one characteristic feature size
and spacing between features. But practical applications may need block copolymers of multiple dimensions patterned or spatially placed over a wafer. his invention to use ink-jet printing to deposit different block copolymer films with high spatial resolution over the substrate is highly enabling in terms of device design
and manufacturing in that you can realize different dimension structures all in one layernealey says. oreover the different dimension patterns may actually be directed to assemble with either the same
or different templates in different regions. he advanced form of ink-jet printing the engineers use to locally deposit block copolymers is called electrohydrodynamic or e-jet printing.
It operates much like the ink jet-printers printers office workers use for printing on paper. he idea is flow of materials from small openings except e-jet is a special high-resolution version of ink jet-printers printers that can print features down
to several hundred nanometersonses says. And because e-jet can naturally handle fluid inks it is suited exceptionally well for patterning solution suspensions of nanotubes nanocrystals nanowires
and other types of nanomaterials. he most interesting aspect of this work is the ability to combine top down techniques of jet printing with â##bottom upâ##processes of self-assembly in a way that opens up new capabilities
in lithographyâ##applicable to soft and hard materials alikerogers says. he opportunities are in forming patterned structures of nanomaterials to enable their integration into real devices.
I am optimistic about the possibilities. esearchers from Hanyang University in Korea also contributed to the study
which received funding from the National Science Foundation and National Research Foundation of Korea t
#Earth s wobble fixes food for ocean creatures Princeton university rightoriginal Studyposted by Catherine Zandonella-Princeton on September 16 2013the cyclic wobble of the Earth on its axis controls the production of ixednitrogen
which in turn affects the Earth s climate and the size of marine fisheries. Researchers report that during the past 160000 years nitrogen fixation rose
and that the ocean biosphere can recover from even the most dramatic ecological changes says second author Daniel Sigman professor of geological
and geophysical sciences at Princeton university. y studying the response of nitrogen fixation to different environmental changes in the Earth s past we have found connections that may ensure that the ocean s fixed nitrogen level will always reboundsigman says. his suggests that an ocean over time has a relatively stable nutrient reservoir
Douglas Capone a professor and chair of biological sciences at the University of Southern California says that the research is notable both for understanding the nitrogen cycle
along with throwing light on the major controls on this key process over long time scales. dditional researchers from Princeton The swiss Institute of technology in Zurich (ETH) and Columbia University Lamont-doherty earth observatory.
and spread diseases such as the ongoing outbreak of Cryptococcus in Canada and the Pacific Northwest of the United states. Though some might disagree most biologists think the purpose of sex is to create diversity among offspring.
Such diversity underpins evolution enabling organisms to acquire new combinations of traits to adapt to their environment.
Studies of a fungus called Cryptococcus show the process of sexual reproduction can result in extra bundles of genetic material
or chromosomes that can be beneficial to the organism s survival. The results are published in the journal PLOS Biology. hese studies turn our view of the functions of sex by 180 degrees
and reveal that sex doesn t just mix up already existing genetic diversity but can actually create it from scratchsays Joseph Heitman the study s senior author and professor and chair of molecular genetics and microbiology at the Duke university School of medicine.
The fungi Cryptococcus neoformans is a global pathogen that primarily infects individuals with compromised immune systems such as HIV/AIDS patients.
It causes more than 600000 deaths a year from cryptococcal pneumonia and meningoencephalitis accounting for a third of all AIDS-related deaths.
Researchers have been interested in the sexual cycle of Cryptococcus because it is the only way this fungal pathogen can produce spores to infect its host.
Though it has two mating types, ##namely and lpha##the vast majority of the fungi found in nature are of the alpha variety.
because if there are two identical genomes coming together the end product should be the same as if the fungi had cloned just itself through asexual reproductionsays Heitman. e were trying to get a sense of is it just spinning its wheels
and his colleagues former fellow Min Ni and current graduate student Marianna Feretzaki grew the microbe in two different ways,
or having more than the normal number of DNA-packaging chromosomes. Aneuploidy is well known to be deleterious in humans causing genetic disorders like Down s syndrome or trisomy 21.
But having an extra chromosome can actually be beneficial in microbes like Cryptococcus where it has been shown to confer drug resistance to the antifungal fluconazole.
In this study the researchers discovered that aneuploidy could lead to beneficial neutral or detrimental changes in the fitness of the offspring.
For example offspring with an extra copy of chromosome 9 or 10 became drug resistant and were able to outcompete their parent
or adaptive the fungi can lose the chromosome just as easily as they gained it. In fact we showed that
and let them lose their extra chromosomes they also lose their new properties and go back to behaving just like their parent did. he key finding he says llustrates how unisexual reproduction introduces limited genetic diversity in clonal populations already well adapted to an environment
which may drive outbreaks of drug resistant pathogenic microbes. eitman is currently looking for aneuploidy in samples from the outbreak of Cryptococcus gattii in the western part of North america to see
#Glass just two atoms thick shatters world record Cornell University rightoriginal Studyposted by Anne Ju-Cornell on September 12 2013a aneof glass so impossibly thin that its individual silicon
Just two atoms in thickness the glass was an accidental discovery says David A. Muller professor of applied
and engineering physics at Cornell University. Scientists at Cornell and Germany s University of Ulm had been making graphene a two-dimensional sheet of carbon atoms in a chicken wire crystal formation on copper foils in a quartz furnace.
They noticed some uckon the graphene and upon further inspection found it to be composed of the elements of everyday glass silicon and oxygen.
They concluded that an air leak had caused the copper to react with the quartz also made of silicon and oxygen.
The work that describes direct imaging of this thin glass was published first in January 2012 in Nano Letters
Besides its sheer novelty Muller says the work answers an 80-year-old question about the fundamental structure of glass.
and they found that it strikingly resembles a diagram drawn in 1932 by W. H. Zachariasenâ##a longstanding theoretical representation of the arrangement of atoms in glass. his is the work that when
I look back at my career I will be most proud ofmuller says. t s the first time that anyone has been able to see the arrangement of atoms in a glass. hat s more two-dimensional glass could someday find a use in transistors by providing a defect-free ultra-thin material that could improve the performance of processors
in computers and smartphones. The National Science Foundation funded the work at Cornell. Source: Cornell Universityyou are free to share this article under the Creative Commons Attribution-Noderivs 3. 0 Unported license 3
The nanoscale building blocks display remarkable strength and resistance to failure despite being more than 85 percent air.
##and manmade products constructed from similar materials has to do with the hierarchical architecture of the biological materialsâ##the way the silica-based skeletons are built up from different structural elements some
of which are measured on the scale of billionths of meters or nanometers. Julia R. Greer professor of materials science and mechanics at the California Institute of technology (Caltech) says the work was inspired by earlier work to fabricate extremely lightweight microtrusses. e designed architectures with building blocks that are less than five microns
long meaning that they are not resolvable by the human eye. onstructing these architectures out of materials with nanometer dimensions has enabled us to decouple the materials strength from their density
and to fabricate so-called structural metamaterials which are very stiff yet extremely lightweight. t the nanometer scale solids have been shown to exhibit mechanical properties that differ substantially from those displayed by the same materials at larger scales.
For example Greer s group has shown previously that at the nanoscale some metals are about 50 times stronger than usual
and some amorphous materials become ductile rather than brittle. e are capitalizing on these size effects
and using them to make real three-dimensional structuresgreer says. In an advance online publication of the journal Nature Materials Greer and her students describe how the new structures were made
and responded to applied forces. The largest structure the team has fabricated thus far using the new method is a one-millimeter cube.
which suggests that the general fabrication technique the researchers developed could be used to produce lightweight mechanically robust small-scale components such as batteries interfaces catalysts
and implantable biomedical devicesgreer says the work could fundamentally shift the way people think about the creation of materials. ith this approach we can really start thinking about designing materials backwardshe says. can start with a property
and say that I want something that has this strength or this thermal conductivity for example. Then I can design the optimal architecture with the optimal material at the relevant size
Next the researchers used a technique called two-photon lithography to turn that design into a three-dimensional polymer lattice.
Then they uniformly coated that polymer lattice with thin layers of the ceramic material titanium nitride (Tin)
and removed the polymer core leaving a ceramic nanolattice. The lattice is constructed of hollow struts with walls no thicker than 75 nanometers. e are now able to design exactly the structure that we want to replicate
and then process it in such a way that it s made out of almost any material class we d likeâ##for example metals ceramics
or semiconductorsâ##at the right dimensionsgreer says. In a second paper scheduled for publication in the journal Advanced Engineering Materials Greer s group demonstrates that similar nanostructured lattices could be made from gold rather than a ceramic. asically once you ve created the scaffold you can use whatever technique
In the Nature Materials work the team tested the individual octahedral cells of the final ceramic lattice
and found that they had an unusually high tensile strength. Despite being subjected repeatedly to stress the lattice cells did not break
Typical ceramics fail because of flawsâ##the imperfections such as holes and voids that they contain. e believe the greater strength of these nanostructured materials comes from the fact that
because it has very thin walls she says e can effectively trick this law by reducing the thickness
and the Army Research Office through the Institute for Collaborative Biotechnologies at Caltech supported the research.
Some of the work was carried out at the Jet propulsion laboratory under a contract with NASA and the Kavli Nanoscience Institute at Caltech provided support and infrastructure.
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#Catalyst makes tiny rods swim to target University of Warwick rightoriginal Studyposted by Anna Blackaby-Warwick on September 10 2013putting a bit of catalyst on the ends of microscopic atchstickscan propel them through water to a specific chemical report researchers.
what the researchers have dubbed chemically otorized microscopic matchsticks. efore now most research seeking to influence the direction of motion of microscopic components have had to use outside influences such as a magnetic field
at the University of Warwick. t may even provide some insight into how rod shapes were selected for self-propelled microscopic shapes in the natural world. he team has now found a way to do it by simply adding a chemical in a specific spot
For the purposes of this experiment the researchers placed silica##manganese oxide eadson the matchstick material and introduced hydrogen peroxide as the chemical fuel in one particular place.
They placed the atchsticksin a mixture alongside ordinary polymer microspheres. When the hydrogen peroxide was added the microspheres continued to move in the direction of convection currents
University of Warwic o
#Laser pinpoints tiniest traces of explosive Michigan State university rightoriginal Studyposted by Layne Cameron-Michigan State on September 9 2013a bomb-detecting laser that can find micro-traces of explosive
and their belongings quicklysays Marcos Dantus chemistry professor at Michigan State university. ot only does it detect the explosive material
Dantusâ##initial spark came from a collaboration with Harvard university that developed a laser that could be used to detect cancer
but has the beam output of a simple presentation pointer. hile working on biomedical imaging I began exploring additional applicationsdantus says. e soon learned how effective it was for detecting traces of hazardous substances from distances up to 10 meters away. s described in the journal Applied Physics Letters the bomb-detecting
laser works as a single beam but uses two pulses. The first resonates with certain chemical frequencies found in explosives.
The second a shadow pulse serves as a reference. A discrepancy between the two pulses indicates the presence of explosive materials. he laser is affected not by the color
With additional funding a standalone prototype could be created in about one year he says. Funding for the research was provided by the Department of Homeland security Science and Technology Directorate.
or motions to the user to guide a child s hand as they play computer games designed to help writing.
The research has been led by Professor Mark Mon-Williams and Liam Hill at the University of Leeds in partnership with the Bradford Institute for Health Research and colleagues at the University of Indiana. n trying to support a child with handwriting
and coordination difficulties one of the major challenges teachers and occupational therapists come up against time and again is limited the time they have to work one-to-one with each childhill says. n this respect haptic robotic technologies have huge potential efficiency benefits. hey provide a means by which children can receive supported practice at a level
which adjusts to their growing abilities without the need for one-to-one interaction with a therapist. anks of these systems could be used simultaneously by multiple children in a clinic
or in the classroom setting under the supervision of a single overseeing professional. esearchers carried out the first United kingdom pilot of the device with a small number of five-to seven-year-old children with a wide range of manual abilities.
All the children found the tasks highly enjoyable and were able to perform them to an acceptable level the test showed.
Differences in performance between children previously identified by their classroom teachers as having handwriting difficulties were also noticeable.
#Use microbes, not pesticides, to boost crop yields Iowa State university Original Studyposted by Fred Love-Iowa State on September 9 2013.
and around crops could pay huge dividends for farmers in the near future thanks to advances in genetic sequencing.
A 21-member team organized by the American Academy of Microbiology established a set of recommendations on how advances in microbiology can be harnessed to improve agriculture.
The recommendations published in the Academy s Colloquium Reports set a goal of increasing yields by 20 percent over the next 20 years by enhancing the use of microbes while reducing the use of pesticides and fertilizers by 20 percent.
and lessen the need for costly fertilizers and pesticides says team member Gwyn Beattie a professor of plant pathology and bacteriology at Iowa State university.
Reaching those goals would drastically cut input costs for farmers and produce a range of environmental benefits.
The sheer complexity involved in making sense of the virtually countless microbes that interact with crops made such an ambitious goal seem outlandish in the past.
But new genetic sequencing technology means the benchmarks outlined in the report are realistic Beattie says. he sort of changes we re talking about have gotten lip service in the past
When crops are optimized with the right genetics and colonized by the right microbes both organisms can flourish.
and protect the environment while enhancing yieldsshe says. e re on our way there. ource:
#Quantum system teleports an atom For the first time physicists have transmitted an atom from one location to another inside an electronic chip.
and more functional electronic chips says Arkady Fedorov of the ARC Centre of Excellence for Engineered Quantum systems
and the School of Mathematics and Physics at the University of Queensland. his is a process by
and a receiver. nce entanglement is created this â##impossible information transfer becomes in fact possible thanks to laws of quantum mechanicsfedorov says. or
the first time the stunning process of quantum teleportation has now been used in a circuit to relay information from one corner of the sample to the other. hat makes our work interesting is the system uses a circuit much like modern computer chips. n our system the quantum
 ventually this technology will be used to create more powerful devices. his research indicates that questions relating to the physics of quantum communication can be addressed using electronic circuits at microwave frequencies. ne may even foresee future experiments in which quantum information will be distributed over larger distances
directly by microwave to optical interfaces for quantum communicationsays Fedorov. Teleportation is expected to find applications in secure communication
University of Queenslan N
#Untangled DNA is how guys become guys University of Queensland rightoriginal Studyposted by Bronwyn Adams-Queensland on September 9 2013.
An enzyme that nravelsdna appears to trigger male development of the embryo a finding that may give greater insight into intersex disorders.
despite having A y chromosome rodents lacking the mjd1aenzyme developed as females. The findings are detailed in a study published in the journal Science.
or female says Peter Koopman a professor from the University of Queensland s Institute for Molecular Bioscience. ost mammals including humans
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#Clay supercapacitors built to handle extreme heat Researchers have used cheap and abundant clay as a key ingredient in a supercapacitor that can operate at very high temperatures.
The supercapacitor could be useful for powering devices in extreme environments On earth and in space. ur intention is to completely move away from conventional liquid
or gel-type electrolytes, which have been limited to low-temperature operation of electrochemical devices, says Arava Leela Mohana Reddy,
lead author and a former research scientist at Rice Unversity who is now an assistant professor at Wayne State university in Detroit. e found that a clay-based membrane electrolyte is a game-changing breakthrough that overcomes one of the key limitations of high
-temperature operation of electrochemical energy devices, Reddy says. y allowing safe operation over a wide range of temperatures without compromising on high energy,
A supercapacitor combines the best qualities of capacitors that charge in seconds and discharge energy in a burst and rechargeable batteries that charge slowly but release energy on demand over time.
The ideal supercapacitor would charge quickly, store energy, and release it as needed. esearchers have been trying for years to make energy storage devices like batteries and supercapacitors that work reliably in high-temperature environments,
but this has been given challenging the traditional materials used to build these devices, explains Pulickel Ajayan,
part of the team of materials scientists at Rice who developed the device. In particular, researchers have struggled to find an electrolyte,
which conducts ions between a battery electrodes, that won break down when the heat is on. Another issue has been finding a separator that won shrink at high temperatures and lead to short circuits.
The separator keeps the electrolyte on the anode and cathode sides of a traditional battery apart
while allowing ions to pass through). ur innovation has been to identify an unconventional electrolyte/separator system that remains stable at high temperatures,
Ajayan says. The researchers solved both problems at once. First, they investigated using room-temperature ionic liquids (RTILS) developed in 2009 by European and Australian researchers.
RTILS show low conductivity at room temperature but become less viscous and more conductive when heated.
Clay has high thermal stability, high sorption capacity, a large active surface area and high permeability, Reddy says,
and is used commonly in muds for oil drilling, in modern construction, in medical applications and as a binder by iron and steel foundries.
After combining equal amounts of RTIL and naturally occurring Bentonite clay into a composite paste
and two current collectors to form a supercapacitor. Tests and subsequent electron microscope images of the device showed no change in the materials after heating it to 200 degrees Celsius.
In fact, Reddy says, there was very little change in the material up to 300 degrees Celsius. They reported their findings in the journal Scientific Reports. he ionic conductivity increases almost linearly until the material reaches 180 degrees,
the supercapacitors were stable through 10,000 test cycles. Both energy and power density improved by two orders of magnitude as the operating temperature increased from room temperature to 200 degrees Celsius, the researchers found.
The team took its discovery a step further and combined the RTIL/clay with a small amount of thermoplastic polyurethane to form a membrane sheet that can be cut into various shapes and sizes,
which allows design flexibility for devices. The Advanced Energy Consortium supported the research o
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