#New mechanism that can lead to blindness discovered An important scientific breakthrough by a team of IRCM researchers led by Michel Cayouette Phd is being published by The Journal of Neuroscience.
These findings could have a significant impact on our understanding of retinal degenerative diseases that cause blindness.
Compartments within a cell are much like different parts of a car explains Vasanth Ramamurthy Phd first author of the study.
in order to power the car's engine proteins need to be in a specific compartment to properly exercise their functions.
Our work identified a new mechanism that explains this process. More specifically we found that a protein called Numb functions like a traffic controller to direct proteins to the appropriate compartments.
This is important because the death of photoreceptor cells is known to cause retinal degenerative diseases in humans that lead to blindness.
Our work therefore provides a new piece of the puzzle to help us better understand how and why the cells die.
We believe our results could eventually have a substantial impact on the development of treatments for retinal degenerative diseases like retinitis pigmentosa
and Leber's congenital amaurosis by providing novel drug targets to prevent photoreceptor degeneration concludes Dr. Cayouette.
According to the Foundation Fighting Blindness Canada millions of people in North america live with varying degrees of irreversible vision loss
#Researchers develop worlds thinnest electric generator Researchers from Columbia Engineering and the Georgia Institute of technology report today that they have made the first experimental observation of piezoelectricity
and the piezotronic effect in an atomically thin material molybdenum disulfide (Mos2) resulting in a unique electric generator
and mechanosensation devices that are optically transparent extremely light and very bendable and stretchable. In a paper published online October 15 2014 in Nature research groups from the two institutions demonstrate the mechanical generation of electricity from the two-dimensional (2d) Mos2 material.
The piezoelectric effect in this material had previously been predicted theoretically. Piezoelectricity is a well-known effect in which stretching or compressing a material causes it to generate an electrical voltage (or the reverse in
which an applied voltage causes it to expand or contract). But for materials of only a few atomic thicknesses no experimental observation of piezoelectricity has been made until now.
The observation reported today provides a new property for two-dimensional materials such as molybdenum disulfide opening the potential for new types of mechanically controlled electronic devices.
This material--just a single layer of atoms--could be made as a wearable device perhaps integrated into clothing to convert energy from your body movement to electricity
and power wearable sensors or medical devices or perhaps supply enough energy to charge your cell phone in your pocket says James Hone professor of mechanical engineering at Columbia and co-leader of the research.
Proof of the piezoelectric effect and piezotronic effect adds new functionalities to these two-dimensional materials says Zhong Lin Wang Regents'Professor in Georgia Tech's School of Materials science and engineering and a co-leader of the research.
The materials community is excited about molybdenum disulfide and demonstrating the piezoelectric effect in it adds a new facet to the material.
Hone and his research group demonstrated in 2008 that graphene a 2d form of carbon is the strongest material.
He and Lei Wang a postdoctoral fellow in Hone's group have been actively exploring the novel properties of 2d materials like graphene
Zhong Lin Wang and his research group pioneered the field of piezoelectric nanogenerators for converting mechanical energy into electricity.
He and postdoctoral fellow Wenzhuo Wu are also developing piezotronic devices which use piezoelectric charges to control the flow of current through the material
just as gate voltages do in conventional three-terminal transistors. There are two keys to using molybdenum disulfide for generating current:
but Zhong Lin Wang notes so an even number of layers cancels out the piezoelectric effect.
For the Nature study Hone's team placed thin flakes of Mos2 on flexible plastic substrates
They then patterned metal electrodes onto the flakes. In research done at Georgia Tech Wang's group installed measurement electrodes on samples provided by Hone's group then measured current flows as the samples were deformed mechanically.
They monitored the conversion of mechanical to electrical energy and observed voltage and current outputs. The researchers also noted that the output voltage reversed sign
when they changed the direction of applied strain and that it disappeared in samples with an even number of atomic layers confirming theoretical predictions published last year.
The presence of piezotronic effect in odd layer Mos2 was observed also for the first time. What's really interesting is we've now found that a material like Mos2 which is not piezoelectric in bulk form can become piezoelectric
and give zero net piezoelectric effect. This adds another member to the family of piezoelectric materials for functional devices says Wenzhuo Wu.
In fact Mos2 is just one of a group of 2d semiconducting materials known as transition metal dichalcogenides all of
which are predicted to have similar piezoelectric properties. These are part of an even larger family of 2d materials
whose piezoelectric materials remain unexplored. Importantly as has been shown by Hone and his colleagues 2d materials can be stretched much farther than conventional materials particularly traditional ceramic piezoelectrics
which are quite brittle. The research could open the door to development of new applications for the material and its unique properties.
This is the first experimental work in this area and is an elegant example of how the world becomes different
Ultimately Zhong Lin Wang notes the research could lead to complete atomic-thick nanosystems that are powered self by harvesting mechanical energy from the environment.
This study also reveals the piezotronic effect in two-dimensional materials for the first time which greatly expands the application of layered materials for human-machine interfacing robotics MEMS and active flexible electronics.
For this study the research team also worked with Tony Heinz David M. Rickey Professor of Optical Communications at Columbia Engineering and professor of physics at Columbia's Graduate school of Arts and Sciences.
The study was supported by the U s. Department of energy (DOE) Office of Basic energy Sciences (BES)( No. DE-FG02-07er46394) and U s. National Science Foundation (DMR-1122594
#Precision printing: Unique capabilities of 3-D printing revealed Researchers at the Department of energy's Oak ridge National Laboratory have demonstrated an additive manufacturing method to control the structure
and properties of metal components with precision unmatched by conventional manufacturing processes. Ryan Dehoff staff scientist and metal additive manufacturing lead at the Department of energy's Manufacturing Demonstration Facility at ORNL presented the research this week in an invited presentation at the Materials science & Technology 2014 conference in Pittsburgh.
We can now control local material properties which will change the future of how we engineer metallic components Dehoff said.
It will help us make parts that are stronger lighter and function better for more energy-efficient transportation and energy production applications such as cars and wind turbines.
Applications from microelectronics to high-temperature jet engine components rely on tailoring of crystallographic texture to achieve desired performance characteristics.
and at this level of detail said Suresh Babu the University of Tennessee-ORNL Governor's Chair for Advanced Manufacturing.
As a result of our work designers can now specify location specific crystal structure orientations in a part. Other contributors to the research are ORNL's Mike Kirka and Hassina Bilheux University of California Berkeley's Anton Tremsin and Texas A&m University's William Sames.
The research was supported by the Advanced Manufacturing Office in DOE's Office of Energy efficiency and Renewable energy.
Story Source: The above story is provided based on materials by Oak ridge National Laboratory y
#A brighter design emerges for low-cost, greener LED light bulbs The phase out of traditional incandescent bulbs in the U s
. and elsewhere as well as a growing interest in energy efficiency has given LED lighting a sales boost. However that trend could be short-lived as key materials known as rare earth elements become more expensive.
Scientists have designed now new materials for making household LED bulbs without using these ingredients. They report their development in ACS'Journal of the American Chemical Society.
LED lighting which can last years longer than conventional bulbs is an energy-efficient alternative. Switching lighting to LEDS over the next two decades reports the U s. Department of energy could save the country $250 billion in energy costs over that period reduce the electricity consumption for lighting by nearly one half
and avoid 1800 million metric tons of carbon emission. White LED bulbs are already on store shelves
but the light is generally colder than the warm glow of traditional bulbs. Plus most of these lights are made with rare earth elements that are increasingly in demand for use in almost all other high-tech devices
thus adding to the cost of the technology. Jing Li's research team set out to solve the issues of material sources and pricing.
The researchers designed a family of materials that don't include rare earths but instead are made out of copper iodide
which is an abundant compound. They tuned them to glow a warm white shade or various other colors using a low-cost solution process.
Combining these features this material class shows significant promise for use in general lighting applications the scientists conclude.
The odorless tasteless element can cause skin discoloration stomach pain partial paralysis and a range of other serious health problems.
and can be collected easily in places where public smoking is allowed it could be part of a low-cost solution for a serious public health issue they say.
#Researchers look to exploit females natural resistance to infection Researchers have linked increased resistance to bacterial pneumonia in female mice to an enzyme activated by the female sex hormone estrogen.
Females are naturally more resistant to respiratory infections than males. Now an international team of scientists has shown that increased resistance to bacterial pneumonia in female mice is linked to the enzyme nitric oxide synthase 3 (NOS3.
They also show that this enzyme is activated ultimately by the release of the female sex hormone estrogen.
The team lead by Professor Lester Kobzik at the Harvard university School of Public health introduced Streptococcus pneumoniae into the lungs of mice to mimic the inhalation of bacteria that occurs naturally as we breathe.
They found that deleting this gene meant that the female mice were no longer more resistant to infection.
The team hope that in the future this knowledge could be used to enhance resistance to common and serious lung infections.
Ultimately this work could be especially useful in reducing risk of secondary bacterial pneumonias during seasonal
or pandemic influenza said Professor Lester Kobzik the senior author. We were pleased quite that the work led us to NOS3-targeting drugs that are already available
and that can indeed improve resistance to pneumonia in our mouse model l
#Researchers turn to 3-D technology to examine the formation of cliffband landscapes A blend of photos
and technology takes a new twist on studying cliff landscapes and how they were formed. Dylan Ward a University of Cincinnati assistant professor of geology will present a case study on this unique technology application at The Geological Society of America's Annual Meeting & Exposition.
The meeting takes place Oct 19-22 in Vancouver. Ward is using a method called Structure-From-Motion Photogrammetry--computational photo image processing techniques--to study the formation of cliff landscapes in Colorado
and Utah and to understand how the layered rock formations in the cliffs are affected by erosion.
To get an idea of these cliff formations think of one of the nation's most spectacular tourist attractions the Grand canyon. The Colorado plateau for example has areas with a very simple sandstone-over-shale layered stratigraphy.
and sediment off that sandstone ends up down in the stream channels on the shale and affects the erosion by those streams explains Ward.
The cliffs walk back by erosion so there's this spectacular staircase of stratigraphy that owes its existence and form to that general process.
From there we can build a 3-D computer model of that landscape. Months of fieldwork in comparison would only produce a fraction of the data that we produce in the computer model says Ward.
Ward says that ultimately examining this piece of the puzzle will give researchers an idea as to how the broader U s. landscape was formed.
The above story is provided based on materials by University of Cincinnati. The original article was written by Dawn Fuller.
Mapping that dense molecular machinery is one of the most promising and challenging frontiers in medicine and biology.
The study--authored by scientists from the U s. Department of energy's Brookhaven National Laboratory Stony Brook University Cold Spring Harbor Laboratory
and Imperial College London--published on Oct 15 2014 in the journal Genes and Development. The genesis of the DNA-unwinding machinery is wonderfully complex
and surprising said study coauthor Huilin Li a biologist at Brookhaven Lab and Stony Brook University.
Errors in copying DNA are found in certain cancers and this work could one day help develop new treatment methods that stall
or break dangerous runaway machinery The research picks up where two previous studies by Li and colleagues left off.
and attaches to specific DNA sites to initiate the entire replication process. The second study revealed how the ORC recruits cracks open
and installs a crucial ring-shaped protein structure (Mcm2-7) that lies at the core of the helicase enzyme.
The key question then was how does a second helicase core get recruited and loaded onto the DNA in the opposite orientation of the first?
To our surprise we found an intermediate structure with one ORC binding two rings said Brookhaven Lab biologist
One step further along the researchers also determined the molecular architecture of the final double-ring structure left behind after the ORC leaves the system offering a number of key biological insights.
We now have clues to how that double-ring structure stably lingers until the cell enters the DNA-synthesis phase much later on in replication said study coauthor Christian Speck of Imperial College London.
and then becomes reactivated to begin its work splitting the DNA. Precision methods close collaborationexamining these fleeting molecular structures required mastery of biology chemistry and electron microscopy techniques.
This three-way collaboration took advantage of each lab's long standing collaboration and expertise said study coauthor Bruce Stillman of Cold Spring Harbor.
Imperial College and Cold Spring Harbor handled the challenging material preparation and functional characterization while Brookhaven and Stony Brook led the sophisticated molecular imaging and three-dimensional image reconstruction.
and recruitment process at intervals of 2 7 and 30 minutes. They then used an electron microscope at Brookhaven to pin down the exact structures at each targeted moment in a kind of molecular time-lapse.
Rather than the light used in a traditional microscope this technique uses focused beams of electrons to illuminate a sample and form images with atomic resolution.
which a computer then reconstructs into three-dimensional structure. This technique is ideal because we're imaging relatively massive proteins here Li said.
but these DNA replication mechanisms consist of tens of thousands of amino acids The entire structure is about 20-nanometers across compared to 4 nanometers for an average protein.
Unraveling the DNA processes at the most fundamental level the focus of this team's work could have far-reaching implications.
The structural knowledge may help others engineer small molecules that inhibit DNA replication at specific moments leading to new disease prevention
and measured how microbes in the seafloor sediments consume the greenhouse gas methane as part of understanding how the Earth works.
and contributing to greenhouse gas accumulation. As a byproduct of this process the microbes create a type of rock known as authigenic carbonate
The rocks range in size and distribution from small pebbles to carbonate pavement stretching dozens of square miles.
a geobiology graduate student in the lab of Victoria Orphan of Caltech. These assemblages are also found in the Gulf of mexico as well as off Chile New zealand Africa Europe
--and pretty much every ocean basin in the world noted Thurber an assistant professor (senior research) in Oregon State's College of Earth Ocean and Atmospheric Sciences The study is important scientists say
because it is unrecognized an sink for a potentially very important greenhouse gas. We found that these carbonate rocks located in areas of active methane seeps are themselves more active Thurber said.
In some ways these rocks are like armies waiting in the wings to be needed called upon when to absorb methane.
#Tool enhances social inclusion for people with autism The University of Alicante has developed together with centres in the UK Spain
and Bulgaria a tool designed to assist people with autism spectrum disorders by adapting written documents into a format that is easier for them to read
The software called Open Book provides synonyms images metaphors and definitions of complex verbs explains Paloma Moreda computer programmer at the University of Alicante.
It provides additional information to understand the main ideas of a document and therefore increases independence
and social inclusion of the users as they gain better access to education employment health care and social activities she adds.
An important feature of the software is that it is personalisable and adapts to the abilities of each person.
In other words the user can choose to just see definitions or images interpretation of metaphors or analyses of a feeling for example.
Furthermore it is applicable to a broad range of documents from school textbooks children's stories and literature.
Although in principle the tool has been designed for people with autism spectrum disorders who generally have difficulties in areas such as communication social interaction
In this regard the researcher points out that Open Book can also be helpful for people with low literacy
or learning difficulties as well as people who are learning a foreign language and the elderly who have problems grasping new words.
The project coordinator was Ruslan Mitkov Professor of Computational linguistics and Language Engineering at the University of Wolverhampton (UK).
#Prostate cancers penchant for copper may be a fatal flaw Like discriminating thieves prostate cancer tumors scavenge
Researchers at Duke Medicine have found a way to kill prostate cancer cells by delivering a trove of copper
The combination approach which uses two drugs already commercially available for other uses could soon be tested in clinical trials among patients with late-stage disease.
This proclivity for copper uptake is something we have known could be an Achilles'heel in prostate cancer tumors as well as other cancers said Donald Mcdonnell Ph d. chairman of the Duke Department of Pharmacology and Cancer Biology and senior author
of a study published Oct 15 2014 in Cancer Research a journal of the American Association of Cancer Research.
Our first efforts were to starve the tumors of copper but that was unsuccessful. We couldn't deplete copper enough to be said effective Mcdonnell.
and then use a drug that requires copper to be effective to attack the tumors.
Mcdonnell and colleagues searched libraries of thousands of approved therapies to identify those that rely on copper to achieve their results.
Disulfiram had at one time been a candidate for treating prostate cancer--it homes in on the additional copper in prostate cancer tumors
--but it showed disappointing results in clinical trials among patients with advanced disease. The Duke team found that the amount of copper cancer cells naturally hoard is not enough to make the cells sensitive to the drug.
along with the disulfiram the combination resulted in dramatic reductions in prostate tumor growth among animal models with advanced disease.
Androgens the male hormones that fuel prostate cancer increase the copper accumulation in the cancer cells.
or similar compounds and copper especially beneficial for men who have been on hormone therapies that have failed to slow tumor growth.
Unfortunately hormone therapies do not cure prostate cancer and most patients experience relapse of their disease to a hormone-refractory
or castration-resistant state Mcdonnell said. Although tremendous progress has been made in treating prostate cancer there is clearly a need for different approaches
and our findings provide an exciting new avenue to explore. Mcdonnell said clinical trials of the combination therapy are planned in upcoming months.
Andrew Armstrong M d. associate professor of medicine was involved with a recent study at Duke testing disulfiram in men with advanced prostate cancer.
While we did not observe significant clinical activity with disulfiram in men with recurrent prostate cancer in our recent clinical trial this new data suggests a potential way forward
and a reason why this trial did not have more positive results Armstrong said. Further clinical studies are warranted now to understand the optimal setting for combining copper with disulfiram
or similar compounds in men with progressive prostate cancer particularly in settings where the androgen receptor is active.
The above story is provided based on materials by Duke Medicine e
#Earths magnetic field could flip within a human lifetime Imagine the world waking up one morning to discover that all compasses pointed south instead of north.
It's not as bizarre as it sounds. Earth's magnetic field has flipped--though not overnight--many times throughout the planet's history.
Its dipole magnetic field like that of a bar magnet remains about the same intensity for thousands to millions of years but for incompletely known reasons it occasionally weakens
and presumably over a few thousand years reverses direction. Now a new study by a team of scientists from Italy France Columbia University and the University of California Berkeley demonstrates that the last magnetic reversal 786000 years ago actually happened very quickly in less than 100 years--roughly a human lifetime.
It's amazing how rapidly we see that reversal said UC Berkeley graduate student Courtney Sprain.
The paleomagnetic data are done very well. This is one of the best records we have so far of
what happens during a reversal and how quickly these reversals can happen. Sprain and Paul Renne director of the Berkeley Geochronology Center and a UC Berkeley professor-in-residence of earth and planetary science are coauthors of the study
which will be published in the November issue of Geophysical Journal International and is now available online.
Flip could affect electrical grid cancer ratesthe discovery comes as new evidence indicates that the intensity of Earth's magnetic field is decreasing 10 times faster than normal leading some geophysicists to predict a reversal within a few
Though a magnetic reversal is a major planet-wide event driven by convection in Earth's iron core there are no documented catastrophes associated with past reversals despite much searching in the geologic and biologic record.
Today however such a reversal could potentially wreak havoc with our electrical grid generating currents that might take it down.
And since Earth's magnetic field protects life from energetic particles from the sun and cosmic rays both
of which can cause genetic mutations a weakening or temporary loss of the field before a permanent reversal could increase cancer rates.
The danger to life would be even greater if flips were preceded by long periods of unstable magnetic behavior.
We should be thinking more about what the biologic effects would be said Renne. Dating ash deposits from windward volcanoes The new finding is based on measurements of the magnetic field alignment in layers of ancient lake sediments now exposed in the Sulmona basin of the Apennine Mountains east of Rome Italy.
The lake sediments are interbedded with ash layers erupted from the Roman volcanic province a large area of volcanoes upwind of the former lake that includes periodically erupting volcanoes near Sabatini Vesuvius and the Alban Hills.
and Volcanology measured the magnetic field directions frozen into the sediments as they accumulated at the bottom of the ancient lake.
Unstable magnetic field preceded 180-degree flipwhether or not the new finding spells trouble for modern civilization it likely will help researchers understand how
and why Earth's magnetic field episodically reverses polarity Renne said. The magnetic record the Italian-led team obtained shows that the sudden 180-degree flip of the field was preceded by a period of instability that spanned more than 6000 years.
Renne is continuing his collaboration with the Italian-French team to correlate the lake record with past climate change.
The above story is provided based on materials by University of California-Berkeley. The original article was written by Robert Sanders.
We are building a telescope that will let us see the sun the way we would see other stars said Phillips who is a staff scientist at the Harvard-Smithsonian Center for Astrophysics.
Better Precision with a Laserthe radial velocity method works by measuring how exoplanet gravity changes the light emitted from its star.
Astronomers measure it by capturing the spectrum of a star on the pixels of a digital camera
The astro-comb works by injecting 8000 lines of laser light into the spectrograph. They hit the same pixels as starlight of the same wavelength.
This creates a comb-like set of lines that lets us map the spectrograph down to 1/10000 of a pixel.
So if I have light on this section of the pixel I can tell you the precise wavelength Phillips explained.
By calibrating the spectrograph this way we can take into account very small changes in temperature or humidity that affect the performance of the spectrograph.
This way we can compare data we take tonight with data from the same star five years from now
Building the green astro-comb was a challenge since the researchers needed to convert red laser light to green frequencies.
They did it by making small fibers that convert one color of light to another.
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