#World's first genetic modification of human embryos reported: Experts consider ethics The team injected 86 embryos
and 71 survived, of which 54 were tested genetically. This revealed that just 28 were spliced successfully, and that only a fraction of those contained the replacement genetic material.
Analysis also revealed a number of'off-target'mutations assumed to be caused by the technique acting in other areas of the genome.
The results reveal serious obstacles to using the method in medical applications. The scientists have tried to head off ethical concerns by using'nonviable'embryos,
which cannot result in a live birth, that were obtained from local fertility clinics. However the work is very controversial,
with some warning it could be the start of a slippery slope towards designer babies.
Below, some experts weigh-in with ethical questions and considerations. Prof Robin Lovell Badge, Crick Institute, on the science:"
"The experiments reported by Junjiu Huang and colleagues (Liang et al) in the journal Protein Cell on gene editing in abnormally fertilised human embryos are,
I expect, the first of several that we will see this year. There has been much excitement among scientists about the power of these new gene editing methods,
and particularly about the CRISPR/Cas9 system, which is relatively simple to use and generally very efficient.
The possibility of using such methods to genetically modify human embryos, and therefore humans, has been on the cards
since these methods were described first, and recently these prospects have been brought to the attention of the public through several commentaries made by senior scientists and commentators,
"Dr Yalda Jamshidi, Senior Lecturer in Human genetics, St george's University Hospital Foundation Trust, said:""Inherited genetic conditions often result
what we call gene therapy and researchers have been working on developing techniques to accomplish this for many years."
and promise to be a powerful approach for many human diseases which don't yet have an effective treatment.
although the CRISPR/Cas9 technique they used can work in the embryo, it can miss the target in the gene
"Prof Shirley Hodgson, Professor of Cancer Genetics, St george's University of London, said:""I think that this is a significant departure from currently accepted research practice.
In the past all the gene therapy research that has been approved by regulatory bodies has been somatic, not germline, because of the potentially unpredictable and heritable effects of germline research.
The fact that these researchers found that there were a number of"off target"mutations resulting from the technique they used is clearly a worry in this context.
Any proposal to do germline genetic manipulation should be considered very carefully by international regulatory bodies before it should be considered as a serious research prospect.
This is because of the obvious concerns about the heritability of the genetic alterations induced and the way in which such research could spread from work on"nonviable"embryos,
"Prof Darren Griffin, Professor of Genetics, University of Kent, said:""Given the widespread use of the CRISPR/Cas9 system, such announcement was inevitable, sooner rather than later.
"Associate professor Peter Illingworth is Medical Director at IVFAUSTRALIA:""This is a fascinating piece of experimental science.
http://www. sciencemediacentre. org/expert-reaction-to-the-application-of-genome-editing-techniques-to-human-embryos/http://www. smc. org. au/expert-reaction-worlds
-first-genetic modification-of-human-embryos-reported-protein-cell l
#Generating broadband terahertz radiation from a microplasma in air Researchers have shown that a laser-generated microplasma in air can be used as a source of broadband terahertz radiation.
They have exploited the underlying physics to reduce the necessary laser power for plasma generation. Researchers at the University of Rochester's Institute of Optics have shown that a laser-generated microplasma in air can be used as a source of broadband terahertz radiation.
In a paper published this week in Optica Fabrizio Buccheri and Xi-Cheng Zhang demonstrate that an approach for generating terahertz waves using intense laser pulses in air--first pioneered in 1993--can be done with much lower power lasers, a major challenge until now.
Ph d. student and lead author Buccheri explains that they exploited the underlying physics to reduce the necessary laser power for plasma generation.
He adds that this can be generated using specific terahertz devices, such as diodes or lasers. However, for spectroscopy applications,
For this, a plasma is needed. Buccheri explains that spectroscopy works by looking at which frequencies are absorbed by certain materials.
Different materials have different spectra--they have peaks and troughs at different frequencies. But depending on the spectral resolution,
"Until now, approaches to use a plasma as a broadband source of terahertz have used commonly an elongated plasma generated by combining together two laser beams of different frequencies, i e.,
The"one-color"approach uses single laser frequency to generate the plasma. Pioneered by Harald Hamster and colleagues in 1993,
it required even higher laser energies and therefore it was explored not further until this recent paper by Buccheri and Zhang.
In these states, the electric field is either perpendicular to the radial axis or radial at each given point."
if by creating a plasma with a laser in one of these"weirder"polarization states
"That didn't work. But when I understood why it didn't work, I really understood the underlying physics."
"He adds that he was then able to exploit the physics to use lower laser energies than previously thought possible to generate broadband terahertz waves in air.
The trick was to replace elongated plasmas, with lengths ranging from few millimeters to several centimeters, with a microplasma, about the width of a human hair.
He thinks that fine tuning the type of laser used and changing the air to a different gas could enable even lower operation powers.
This makes it easier for potentially coupling the terahertz waves to a wave guide on a microchip
Nanoscopic lasers--first demonstrated in 2009--are only found in research labs today. They are,
We believe this work represents a conceptual and practical engineering advance for on-demand, reversible control of light from nanoscopic sources."
"Odom is Board of Lady Managers of the Columbian Exposition Professor of Chemistry in the Weinberg College of Arts and Sciences.
The liquid nanolaser in this study is not a laser pointer but a laser device on a chip,
The laser's cavity is made up of an array of reflective gold nanoparticles, where the light is concentrated around each nanoparticle
and then amplified. In contrast to conventional laser cavities, no mirrors are required for the light to bounce back and forth.
the nanoparticle cavity stays fixed and does not change; only the liquid gain around the nanoparticles changes.
The main advantages of very small lasers are: Some technical backgroundplasmon lasers are promising nanoscale coherent sources of optical fields
because they support ultra-small sizes and show ultra-fast dynamics. Although plasmon lasers have been demonstrated at different spectral ranges, from the ultraviolet to near-infrared,
a systematic approach to manipulate the lasing emission wavelength in real time has not been possible. The main limitation is that only solid gain materials have been used in previous work on plasmon nanolasers;
hence, fixed wavelengths were shown because solid materials cannot easily be modified. Odom's research team has found a way to integrate liquid gain materials with gold nanoparticle arrays to achieve nanoscale plasmon lasing that can be tuned dynamical, reversibly and in real time.
The use of liquid gain materials has two significant benefits: These nanoscale lasers can be mass-produced with emission wavelengths over the entire gain bandwidth of the dye.
Thus, the same fixed nanocavity structure (the same gold nanoparticle array) can exhibit lasing wavelengths that can be tuned over 50 nanometers, from 860 to 910 nanometers,
simply by changing the solvent the dye is dissolved in n
#Scientists create cheaper magnetic material for cars, wind turbines Karl A. Gschneidner and fellow scientists at the U s. Department of energy's Ames Laboratory have created a new magnetic alloy that is an alternative to traditional rare-earth permanent magnets.
The new alloy--a potential replacement for high-performance permanent magnets found in automobile engines and wind turbines--eliminates the use of one of the scarcest and costliest rare earth elements, dysprosium,
and instead uses cerium, the most abundant rare earth. The result, an alloy of neodymium, iron and boron co-doped with cerium and cobalt
is a less expensive material with properties that are competitive with traditional sintered magnets containing dysprosium.
Experiments performed at Ames Laboratory by postdoctoral researcher Arjun Pathak, and Mahmud Khan (now at Miami University) demonstrated that the cerium-containing alloy's intrinsic coercivity--the ability of a magnetic material to resist demagnetization--far exceeds that of dysprosium-containing magnets at high temperatures.
The materials are at least 20 to 40 percent cheaper than the dysprosium-containing magnets.""This is quite exciting result;
we found that this material works better than anything out there at temperatures above 150°C,
"said Gschneidner.""It's an important consideration for high-temperature applications.""Previous attempts to use cerium in rare-earth magnets failed
because it reduces the Curie temperature--the temperature above which an alloy loses its permanent magnet properties.
But the research team discovered that co-doping with cobalt allowed them to substitute cerium for dysprosium without losing desired magnetic properties.
Finding a comparable substitute material is key to reducing manufacturing reliance on dysprosium; the current demand for it far outpaces mining
and Frederik E. Pinkerton of General motors R&d Center. The research was supported by the U s. Department of energy's ARPA-E REACT program (Advanced Research Projects Agency-Energy-Rare earth Alternatives in Critical Technologies) which develops cost-effective alternatives to rare earths,
the naturally occurring minerals with unique magnetic properties that are used in electric vehicle (EV) motors, and wind generators.
The REACT projects identify low-cost and abundant replacement materials for rare earths while encouraging existing technologies to use them more efficiently l
#Mass and shape of single molecules revealed The work was led by Professor John Sader at the University of Melbourne's School of Mathematics and Statistics and Professor Michael Roukes of the California Institute of technology.
It features in a paper published in this month's issue of Nature Nanotechnology. Prof Sader says this technique revolutionises molecule detection for biologists,
or indeed anyone who wants to measure extremely small objects. To discover what a specimen looks like,
researchers attach it to a tiny vibrating device, known as a nanoelectromechanical system (NEMS) resonator.""One standard way to tell the difference between molecules is to weigh them using a technique called mass spectrometry.
The problem is that different molecules can have the same weight. Now, we can tell them apart by identifying their shape,
"This technology is built on a new mathematical algorithm that we developed, called inertial imaging. It can be used as a diagnostic tool
so that an electromagnetic field can interact with them. This interaction is measured then, which gives vital information on the molecule's mass-to-charge ratio.
It's a lot like attaching a drop of solder on the string of a guitar--it changes its vibration frequency and also its tone."
"A common way to decipher molecular structures is to use x-ray crystallography. This complicated method involves purifying and crystallising the molecules,
because the structure of a molecule in its natural environment can be different. California Institute of technology Professor Michael Roukes says NEMS
and inertial imaging could prove very useful for biological scientists.""You can imagine situations where you don't know exactly what you are looking for,
where you are in discovery mode, and you are trying to figure out the body's immune response to a particular pathogen, for example,
"Prof Roukes said.""This new technique adds another piece of information to aid our identification of molecules,
which could prove useful in biomedical applications, among other uses
#Electrical power converter allows grid to easily accept power from renewable energy Doctoral student Joseph Carr developed the system with his adviser, Juan Balda, University Professor and head of the department of electrical engineering.
Innovations in this field are critical as the United states moves toward integration of renewable energy sources to the national power grid.
The U s. Department of energy pursued and was granted a U s. patent for the technology and is now seeking licensing opportunities for potential commercialization.
when doctoral students who invest many hours working on various research ideas are rewarded with a patent, "Balda said."
"At the same time, it is an indication of research work that several faculty members and their students are doing in the field of future energy systems."
"The availability and use of renewable energy sources, such as solar, geothermal and wind, and their associated harvesting systems increase the need for new power converters that can efficiently convert diverse energy sources to work across modern electrical grid systems.
Current renewable energy conversion systems are bulky, inefficient and struggle to accept multiple inputs from diverse sources.
Its simplified control system uses power converters to allow connection of a variety of power sources to a small, high-frequency transformer.
it produces stable electricity ready to be supplied to the electrical grid system. Carr received his doctorate from the university in 2011.
He Was distinguished a Doctoral Fellow from 2005 to 2009 and co-authored nine articles published in journals
He now works for ABB, a power company in Raleigh, North carolina. Balda has been a professor at the university since 1989.
His main research interests are power electronics, electric power distribution systems, motor drives and electric power quality.
He is a senior member of the IEEE and member of the Power Electronics and Industry Applications Societies.
As associate director of the National Center for Reliable Electric power Transmission, a 7, 000-square-foot, $5-million power electronic test facility at the University of Arkansas
Balda is at the center of a critical corps of U of A researchers investigating solid-state solutions for the nation's electric power grid d
#Researchers train computers to identify gene interactions in human tissues A multi-year study led by researchers from the Simons Center for Data analysis (SCDA)
and major universities and medical schools has broken substantial new ground, establishing how genes work together within 144 different human tissues
and cell types in carrying out those tissues'functions. The paper, to be published online By nature Genetics on April 27,
also demonstrates how computer science and statistical methods may combine to aggregate and analyze very large--and stunningly diverse--genomic'big data'collections.
Led by Olga Troyanskaya, deputy director for genomics at SCDA the team collected and integrated data from about 38,000 genome-wide experiments (from an estimated 14,000 publications.
These datasets necessarily contain not only information about cells'RNA/protein functions, but also information from individuals diagnosed with a variety of illnesses.
Then, combining that tissue-specific functional signal with the relevant disease's DNA-based genome-wide association studies (GWAS),
and diseases that would otherwise be undetectable. The resulting technique, which they called a'network-guided association study,
thus integrates quantitative genetics with functional genomics to increase the power of GWAS and identify genes underlying complex human diseases.
And because the technique is driven completely data Netwas avoids bias toward better-studied genes and pathways, permitting discovery of novel associations.
SCDA director Leslie Greengard says, "Olga and her collaborators have demonstrated that extraordinary results can be achieved by merging deep biological insight with state-of-the-art computational methods,
and applying them to large-scale, noisy and heterogeneous datasets.""The result of their efforts was 144 functional gene interaction networks for organs as diverse as the kidney, the liver and the whole brain.
The paper goes on to describe functional gene disruptions for diseases such as hypertension, diabetes and obesity.
Many human cell types important to disease cannot be studied by traditional direct experimentation, so the ability to instead work with these rich datasets was a critical workaround."
"A key challenge in human biology is that genetic circuits in human tissues and cell types are very difficult to study experimentally,
"says Troyanskaya, who also is a professor in the computer science department and the Lewis-Sigler Institute for Integrative Genomics at Princeton university."
"For example, the podocyte cells in the kidneys that perform the kidney's filtering function cannot be isolated for study in the lab,
nor can the function of genes be identified by genome-scale experiments. Yet we need to understand how proteins interact in these cells
and in many other disease-relevant tissues and cell types.""These findings have important implications for our understanding of normal gene function,
"Biomedical researchers can use these networks and the pathways that they uncover to understand drug action and side effects in the context of specific disease-relevant tissues,
and to repurpose drugs,"Troyanskaya says.""These networks can also be useful for understanding how various therapies work and to help with developing new therapies."
"The researchers have created also an online resource so that other scientists may use Netwas and access the tissue-specific networks.
The team created an interactive server, the Genome-scale Integrated Analysis of Networks in Tissues, or GIANT.
GIANT allows users to explore the networks, compare how genetic circuits vary across tissues, and analyze data from genetic studies to find genes that cause disease.
Aaron K. Wong, a data scientist at SCDA and formerly a graduate student in the computer science department at Princeton, led the way in creating GIANT."
"Our goal was to develop a resource that was accessible to biomedical researchers, "he says."
"For example, with GIANT, researchers studying Parkinson's disease can search the substantia nigra network, which represents the brain region affected by Parkinson's,
to identify new genes and pathways involved in the disease.""Wong is one of three co-first authors of the paper.
The paper's other two co-first authors are Arjun Krishnan, a postdoctoral fellow at the Lewis-Sigler Institute;
and Casey S. Greene, assistant professor of genetics at Dartmouth College, who was a postdoctoral fellow with the Troyanskaya group from 2009 to 2012.
Other key collaborators on this study were Emanuela Ricciotti, Garret A. Fitzgerald and Tilo Grosser of the pharmacology department and the Institute for Translational Medicine and Therapeutics at the Perelman School of medicine, University of Pennsylvania;
Daniel I. Chasman of Brigham and Women's Hospital and Harvard Medical school in Boston; and Kara Dolinski at the Lewis-Sigler Institute at Princeton university."
"This is an exciting time in biomedical research, and I believe we are still at the early stages of developing new ways to think about biological networks and their control,
"Greengard says s
#New material for creating artificial blood vessels Arteriosclerotic vascular disorders are one of the most common causes of death in industrialized countries.
Thanks to a joint project undertaken by TU Wien and the Medical University of Vienna,
TUW has developed therefore new polymers.""These are so-called thermoplastic polyurethanes, "explains Robert Liska from the Institute of Applied Synthetic Chemistry of Vienna University of Technology."
"By selecting very specific molecular building blocks we have succeeded in synthesizing a polymer with the desired properties."
"A thin polymer thread spun into tubesto produce the vascular prostheses, polymer solutions were spun in an electrical field to form very fine threads and wound onto a spool."
"The wall of these artificial blood vessels is very similar to that of natural ones, "says Heinz Schima of the Medical University of Vienna.
The polymer fabric is slightly porous and so, initially, allows a small amount of blood to permeate through
and this enriches the wall with growth factors. This encourages the migration of endogenous cells.
The interaction between material and blood was studied by Martina Marchetti-Deschmann at TU Wien using spatially resolved mass spectrometry.
The new method has already proved very successful in experiments with rats.""The rats'blood vessels were examined six months after insertion of the vascular prostheses,
"says Helga Bergmeister of Meduni Vienna.""We did not find any aneurysms, thromboses or inflammation.
Endogenous cells had colonized the vascular prostheses and turned the artificial constructs into natural body tissue."
The project was awarded recently PRIZE prototype funding from Austria Wirtschaftsservice (AWS. A few more preclinical trials are necessary before the artificial blood vessels can be used in humans.
However, based on the results so far, the research team is very confident that the new method will prove itself for use in humans in a few years time e
#Researchers develop new computer-based vision screening test for young children Many eye disorders in young children are asymptomatic
A new report published in the Journal of the American Association for Pediatric Ophthalmology and Strabismus (AAPOS) describes the effectiveness of a new computer-based vision-screening test, the Jaeb Visual acuity Screener (JVAS),
which is suitable for use in schools and pediatrician's offices.""Broad adoption of this tool would result in a more standardized approach to pediatric vision screening in diverse medical
and community office settings,"commented lead investigator Tomohiko Yamada, OD, of the Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota."
"In comparison to traditional vision testing methodologies, this software-based tool provides the advantage of running on any windows-based PC in a pediatrician's examination room--avoiding testing in distracting office hallways."
"JVAS is computerized a screening program developed by the Jaeb Center for Health Research that is designed to identify children with subnormal visual acuity in a rapid and reproducible manner.
It uses a set testing algorithm to minimize subjective tester bias. It also uses age-specific visual acuity standards to provide a simple pass/fail result for four age groups (3, 4, 5 or 6,
who then received a complete eye examination by an optometrist, which served as the study gold standard.
The examining optometrist was kept unaware of the initial JVAS vision screening results. No children who already wore glasses,
had been treated for amblyopia, or had undergone ocular surgery were included in the screening. The average screening time was 84 seconds, with a range of 23 to 357 seconds across all age groups.
There were three different failure criteria evaluated:(1) failure to identify at least three of any four normal threshold letters in either eye;(
Of the 65 children failing the gold standard examination, 86%failed for reduced visual acuity (56), 35%for hyperopia (23), 23%for astigmatism (15), 11%for anisometropia (7), 9%for myopia (6),
and 5%for strabismus (3), with some patients failing the gold standard for more than one reason.
For the 56 children with reduced visual acuity, the primary cause assigned hierarchically was uncorrected refractive error in 31 of 56 (55%),unilateral amblyopia in 7 (13%),bilateral amblyopia in 8 (14%
and the investigators encourage elementary school nurses, pediatricians, and other professionals who work with children ages 3-7 years to download
#When mediated by superconductivity, light pushes matter million times more The results of the research were published in Nature Communications in April.
"explains theorist Jani Tuorila from the University of Oulu. In the work reported here, the researchers combine their knowledge on experimental and theoretical physics,
and show how the strength of the radiation pressure coupling can be increased considerably. They placed a superconducting island in between the electromagnetic field
and the oscillator to mediate the interaction.""In the measurements, we exploited the Josephson coupling of the superconducting junctions,
especially its nonlinear character,"explains Juha Pirkkalainen from Aalto University, the postdoctoral researcher who conducted the measurements.
--With the superconducting island, the radiation pressure increased a millionfold the value we had achieved previously, reports the supervisor of the experimental group, professor Mika Sillanp##from Aalto University.
Because of the increased radiation pressure coupling, the oscillator observes the electromagnetic field with the precision of a single photon.
the measurement of quantum information from an oscillator nearly visible to the naked eye,"explains professor Tero Heikkil#from the University of Jyv#skyl#who was in charge of the theoretical studies.
#Chemists strike nano-gold: Four new atomic structures for gold nanoparticle clusters Led by University of Nebraska-Lincoln chemistry professor Xiao Cheng Zeng,
and former UNL visiting professor Yi Gao, new research has revealed four atomic arrangements of a gold nanoparticle cluster.
The arrangements exhibit much lower potential energy and greater stability than a standard-setting configuration reported last year by a Nobel prize-winning team from Stanford university.
The modeling of these arrangements could inform the cluster's use as a transporter of pharmaceutical drugs
and as a catalyst for removing pollutants from vehicular emissions or other industrial byproducts, Zeng said.
Sixteen of the gold atoms form the molecule's core; the remainder bond with the sulfur
and hydrogen to form a protective coating that stems from the core. Differences in atomic arrangements can alter molecular energy and stability,
with less potential energy making for a more stable molecule. The team calculates that one of the arrangements may represent the most stable possible structure in a molecule with its composition."
"Our group has helped lead the front on nano-gold research over the past 10 years,
"said Zeng, an Ameritas University Professor of chemistry.""We've now found new coating structures of much lower energy,
The structure of the molecule's gold core was previously detailed by the Stanford team.
and sulfur-hydrogen pairs surrounding the core. The researchers already knew that the atomic coating features staple-shaped linkages of various lengths.
By combining this information with their knowledge of how many atoms reside outside the core the team reduced the number of potential arrangements from millions to mere hundreds."
and then we computed their energies to find the most stable ones.""Without those rules, it's like finding a needle in the Platte river.
"The researchers resorted to the computational approach because of the difficulty of capturing the structure via X-ray crystallography or single-particle transmission electron microscopy, two of the most common imaging methods at the atomic scale.
Knowing the nanoparticle's most stable configurations, Zeng said, could allow biomedical engineers to identify appropriate binding sites for drugs used to treat cancer and other diseases.
The findings could also optimize the use of gold nanoparticles in catalyzing the oxidation process that transforms dangerous carbon monoxide emissions into the less noxious carbon dioxide,
he said d
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