#New target identified for inhibiting malaria parasite invasion Boston, MA#A new study led by researchers at Harvard T. H. Chan School of Public health finds that a malaria parasite protein called calcineurin is essential for parasite invasion into red blood cells.
Human calcineurin is already a proven target for drugs treating other illnesses including adult rheumatoid arthritis and lupus,
and the new findings suggest that parasite calcineurin should be a focus for the development of new antimalarial drugs. ur study has great biological and medical significance, particularly in light of the huge disease burden of malaria,
said senior author Manoj Duraisingh, John Laporte Given Professor of Immunology and Infectious diseases. s drug resistance is a major problem for malaria control and eradication,
it is critical that that we continue to develop new antimalarials that act against previously unexploited targets in the parasite to keep priming the drug pipeline.
The research team at Harvard Chan School used cutting edge genetic and cell biological methods to provide definitive evidence of the essentiality and function of calcineurin in parasite invasion.
Studies from a group at the University of Glasgow which are published in the same issue of the journal,
show the importance of calcineurin through different stages of the malaria life-cycle, implicating the protein as a potential target for blocking malaria transmission.
In addition to opening the door to potential new malaria treatments, these studies suggest that calcineurin could be targeted to treat other parasitic diseases.
Researchers at Boston College working in collaboration with the Harvard Chan group showed that calcineurin is also important for cellular attachment by a related parasite that causes toxoplasmosis. ur study shows that the ability of malaria parasites to engage red blood cells is driven by an ancient mechanism
for cellular attachment said lead author Aditya Paul, a postdoctoral researcher at the Harvard Chan School. n addition to a possible drug target,
calcineurin underlies a very basic aspect of parasite biology. p
#What your clothes may say about you Moving closer to the possibility of aterials that computeand wearing your computer on your sleeve,
researchers at the University of Pittsburgh Swanson School of engineering have designed a responsive hybrid material that is fueled by an oscillatory chemical reaction
and can perform computations based on changes in the environment or movement, and potentially even respond to human vital signs.
The material system is sufficiently small and flexible that it could ultimately be integrated into a fabric
or introduced as an inset into a shoe. Anna C. Balazs, Phd, Distinguished Professor of Chemical and Petroleum Engineering
and Steven P. Levitan, Phd, John A. Jurenko Professor of Electrical and Computer engineering, integrated models for self-oscillating polymer gels and piezoelectric micro-electric-mechanical systems to devise a new
reactive material system capable of performing computations without external energy inputs, amplification or computer mediation. Their research, Achieving synchronization with active hybrid materials:
Coupling self-oscillating gels and piezoelectric (PZ) films, appeared online June 24, 2015 in the journal Scientific Reports, published By nature (DOI:
By working with Dr. Victor V. Yashin, Research Assistant professor of Chemical and Petroleum Engineering and lead author on the paper,
In effect, these different oscillatory patterns form a type of emory allowing the material to be used for computation.
however, the computations would not be general purpose, but rather specific to pattern-matching and recognition,
and respond accordingly, thereby performing the actual computing. eveloping so-called aterials that computeaddresses limitations inherent to the systems currently used by researchers to perform either chemical computing or oscillator-based computing.
Chemical computing systems are limited by both the lack of an internal power system and the rate of diffusion as the chemical waves spread throughout the system,
Further, oscillator-based computing has not been translated into a potentially wearable material. The hybrid BZ-PZ model,
NSF, University of Pittsburg
#NRL Researchers First to Detect Spin Precession in Silicon nanowires Scientists at the U s. Naval Research Laboratory (NRL) have reported the first observation of spin precession of spin currents flowing in a silicon nanowire
(NW) transport channel, and determined spin lifetimes and corresponding spin diffusion lengths in these nanoscale spintronic devices.
The spin currents were injected electrically and detected using ferromagnetic metal contacts with a tunnel barrier consisting of single layer graphene between the metal and silicon NW.
The ferromagnetic metal/graphene tunnel barrier contacts used to inject and detect spin appear as blue,
the gold ohmic reference contacts appear as yellow, and the green line is the silicon nanowire transport channel.
The bright dot on the end of the nanowire is used the gold nanoparticle to seed the nanowire growth.
The NRL research team observed spin precession (the Hanle effect) for both the spin-polarized charge near the contact interface and for pure spin currents flowing in the NW channel.
The use of graphene as the tunnel barrier provides a low-resistance area product contact
because it smoothly bridges the NW and minimizes complicated magnetic domains that otherwise compromise the magnetic behavior.
The team discovery is an essential step toward the realization of highly scaled semiconductor spintronic devices.
Semiconductor nanowires provide an avenue to further reduce the ever-shrinking dimensions of transistors. Including electron spin as an additional state variable offers new prospects for information processing,
enabling future nonvolatile, reprogrammable devices beyond the current semiconductor technology roadmap. Silicon is an ideal host for such a spin-based technology
explains principal investigator Dr. Olaf van Erve. Realization of spin-based Si NW devices requires efficient electrical spin injection and detection,
which depend critically on the interface resistance between a ferromagnetic metal contact and the NW.
This is especially problematic with semiconducting NWS because of the exceedingly small contact area which can be of order 100 nm2.
Researchers have shown standard oxide tunnel barriers to provide good spin injection into planar Si structures,
and used a graphene tunnel barrier contact that produces excellent spin injection and also satisfies several key technical criteria:
a highly uniform tunnel layer with well-controlled thickness, clean magnetic switching characteristics for the magnetic contacts,
and compatibility with both the ferromagnetic metal and silicon NW. Using intrinsic 2d layers such as graphene
or hexagonal boron nitride as tunnel contacts on nanowires offers many advantages over conventional materials deposited by vapor deposition (such as Al2o3
or Mgo), enabling a path to highly scaled electronic and spintronic devices. The use of multilayer rather than single layer graphene in such structures may provide much higher values of the tunnel spin polarization because of band structure derived spin filtering effects predicted for selected ferromagnetic metal/multi
-layer graphene structures. This increase would further improve the performance of nanowire spintronic devices by providing higher signal to noise ratios
and corresponding operating speeds, advancing the techological applications of nanowire devices. The NRL research team includes Dr. Olaf van Erve, Dr. Adam Friedman, Dr. Connie Li,
and Dr. Berend Jonker from the Materials science and Technology Division, and Dr. Jeremy Robinson from the Electronics Science and Technology Division i
#Actuators that mimic ice plants Engineers developing moveable robot components may soon take advantage of a trick plants use.
Researchers at the Max Planck Institute of Colloids and Interfaces in Potsdam and Harvard university in Cambridge (USA) have devised porous materials that could serve as actuators, or motors.
The dynamic mechanism of the material resembles that of some plant tissues. When pressure is increased in the pores of the polymer,
the structure swells and expands in a preferred direction. In this way, the researchers mimic the mechanism by
The walls of the cells are made of a non-swellable polymer; a swellable polymer fills the interior of the chambers.
If the pressure inside the cells increases, for example, because the swellable polymer absorbs liquids, the structure expands in one direction.
Advanced Materials Interfaces/MPI of Colloids and Interfacesif you enjoy walking in the woods, you may well be familiar with the phenomenon.
because these movements are driven not by energy from metabolic processes but solely by physical mechanisms. From a biological point of view, there no other way to achieve this.
After all, the material for example that of a fallen pinecone is already dead. Researchers at the Max Planck Institute of Colloids and Interfaces in Potsdam have investigated now in detail how the material properties, geometry and arrangement of the cells affect macroscopic movements.
To this end, they developed a computer simulation as well as tissue-like materials from a porous polymer in
which the pores roughly model the cells in the biological material. What they found is fascinating.
In one case the scientists tested three different honeycomb structures made up of the same basic cell.
as the latter would require significantly more energy. When the air or fluid pressure inside the cells was increased
two of the three honeycomb structures moved preferentially in one direction but formed different new cell geometries in the process.
who heads the Biomimetic Actuation and Tissue Growth Group in the Biomaterials Department of the Max Planck Institute in Potsdam,
made a significant contribution to the recent work. e now have a very flexible lever
Moveable parts of such robots, the actuators, might consist of a porous polymer with precisely defined pore properties. he actual motion could then be controlled by compressed air or an expandable fluid in the pores
The researchers were delighted also that the theoretical predictions from the computer simulation almost perfectly matched the results of their tests on synthesized porous polymer materials.
Only the amount of expansion was somewhat less in the experiment than in the virtual simulation. his means that wee able to design such materials on the computer
says Dunlop. Synthetic polymer honeycomb structures from a 3d printerthe composition of the cell walls plays a key role in the expansion process in the relevant cells of pinecones
The researchers simulated this structure for their practical experiments by bonding two different swellable polymer layers together.
The scientists envisage using porous polymer materials whose pores are filled with a hygroscopic fluid, for example a superabsorbing hydrogel, in future practical applications.
after all, masters in the mechanics of opening and closing again at the right time. Source:
The work will be of interest to those considering graphene elements in flexible touchscreens or memories that store bits by controlling electric dipole moments of carbon atoms
But curvature in graphene compresses the electron clouds of the bonds on the concave side and stretches them on the convex side,
the characteristic that controls how polarized atoms interact with external electric fields. The researchers who published their results this month in the American Chemical Society Journal of Physical chemistry Letters discovered they could calculate the flexoelectric effect of graphene rolled into a cone of any size and length.
and then figure out their cumulative effect They suggested their technique could be used to calculate the effect for graphene in other more complex shapes, like wrinkled sheets or distorted fullerenes,
several of which they also analyzed. hile the dipole moment is zero for flat graphene or cylindrical nanotubes,
Carbon nanotubes, seamless cylinders of graphene, do not display a total dipole moment, he said. While not zero, the vector-induced moments cancel each other out.
in which the balance of positive and negative charges differ from one atom to the next, due to slightly different stresses on the bonds as the diameter changes.
he said. t can permit one to locally vary the work function and to engineer the band-structure stacking in bilayers or multiple layers by their bending.
more cidicor asic, depending on the curvature in the 3-D carbon architecture
#Helium alloonsoffer new path to control complex materials Researchers at the Department of energy Oak ridge National Laboratory have developed a new method to manipulate a wide range of materials
advances the understanding and use of complex oxide materials that boast unusual properties such as superconductivity and colossal magnetoresistance but are notoriously difficult to control.
pulling or pushing of the structure triggers changes in many different electronic properties. This ripple effect complicates scientistsability to study
but they anticipate the technique will be widely applicable to both functionality driven materials science research
The team work is a step toward bringing complex materials into commercial applications, which would greatly benefit from the ability to tune material properties with processing similar to current semiconductor technologies. ur strain doping technique demonstrates a path to achieving this need,
as it can be implemented using established ion implantation infrastructure in the semiconductor industry, Ward said. The method uses a low energy ion gun to add small numbers of helium ions into the material after it has been produced.
The process is also reversible; the helium can be removed by heating the material to high temperatures in vacuum.
Previously developed strain tuning methods modify all directions in a material and cannot be altered or reversed afterwards. e can easily control the amount of strain
The study was supported by the Department of energy Office of Science and used resources at the Center for Nanophase Materials sciences, a DOE Office of Science User Facility at ORNL.
#New nanogenerators collect friction energy from rolling tires Team of engineers from University of Wisconsin-Madison and a collaborator from China have developed a new nanogenerator that is able to generate power from friction created by rolling
tires of the car. As with a big part of today automotive technological innovations, it is aimed at efficiency.
In the future such technology could help harvest otherwise wasted energy to squeeze just that extra bit of efficiency out of cars and other vehicles.
The nanogenerator harvests the wasted tire friction energy by relying on the triboelectric effect. It is the electric charge that results from the contact or rubbing together of two dissimilar objects.
The generator harnesses energy from the changing electric potential between the pavement and a vehicle wheels.
Scientists said that it could become a very useful way to use the energy that is usually wasted due to friction taking advantage of this lost energy would improve efficiency,
which is a major goal in today automotive industry. Professor Xudong Wang, one of the authors of the study, noted that he friction between the tire
and the ground consumes about 10%of a vehicle fueland, since that energy is wasted simply,
f we can convert that energy, it could give us very good improvement in fuel efficiency Improving fuel efficiency would benefit everyone it would help automotive industry meet new strict regulations for emissions,
make traveling just that little bit cheaper and would improve energy efficiency which would benefit environmental causes as well.
The technology is depending on an electrode integrated into a segment of the tire. When it comes into contact with the ground,
the friction between those two surfaces ultimately produces an electrical charge-a type of contact electrification known as the triboelectric effect.
The segment should not cause any disadvantages to the handling and performance of the car.
To test the technology team used a toy car with LED LIGHTS. Engineers attached an electrode to the tires of the toy car
and watched the LED LIGHTS as the car was rolling forward and they flashed on and off as electrodes came with contact with the surface.
The friction was strong enough for the electrodes to harvest enough energy to power the lights,
which means that scientists confirmed the idea that wasted friction energy can be collected and reused.
Engineers also determined that the amount of energy harnessed is directly related to the weight of a car
and the speed it is going at. It means that different vehicles would waste different amounts of energy
and different percentage of it could be saved using this method. However, scientists estimated that fuel efficiency could be improved by as much as 10%,given 50%friction energy conversion efficiency.
This is a very significant improvement. As cars are supposed to be greener and greener, everyone involved will have to look for new innovative ways to improve efficiency.
This is always largely about collecting wasted energy. That is why this technology has a huge potential
and 10%savings in terms of fuel consumption are pretty big leap forward. But, as usual, we will have to wait
and see how these nanogenerators develop and when they will be introduced for practical application c
#Ultra-stable JILA Microscopy Technique Tracks Tiny Objects for Hours JILA researchers have designed a microscope instrument
so stable that it can accurately measure the 3d movement of individual molecules over many hoursundreds of times longer than the current limit measured inseconds.
JILA instrument for accurately tracking microscopic objects such as DNA molecules for many hours. The microscope is on the left.
The sample is mounted on the black block on top of the silver stage. The lasers and optics are on the right.
Image credit: Burrus/NISTTHE technology was designed to track the machinery of biological cells, down to the tiniest bits of DNA, a single ase pairof nucleotides among the 3 billion of these chemical units in human genes.
But the instrument could be useful well beyond biology, biochemistry and biophysics, perhaps in manufacturing.
JILA is a partnership of the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder. his technology can actively stabilize two items relative to each other with a precision well below one nanometer at room temperature,
JILA/NIST physicist Tom Perkins says. his level of 3d stability may start to interest the nanomanufacturing world,
when they look at making and characterizing things on the single-nanometer scale. he work builds on JILA world-leading expertise in measuring positions of microscopic objects.
The latest tweaks extend stability for a much longer time period, many hours at a time. With the longer observation times, researchers can see more successive steps of molecular motors, for instance.
These biochemical processes are responsible for a broad range of movement in living organisms, including moving molecules around the interior of a cell or copying DNA into another form of genetic material, RNA.
The new JILA instrument also can aid in measuring individual proteins as they fold into specific positions
a process required for them to work properly. Until now, researchers had difficulty detecting more than a few individual,
one-base-pair steps in succession before instrumental riftwould blur the signal. Observing such sets of repetitive steps is very rare.
The instrument must be stable to within about one-tenth of a nanometer (1 angstrom to biologists, equivalent to the diameter of a hydrogen atom.
it can reliably achieve tenth of a nanometer stability for up to 100 seconds at a time. And it can do this over and over again for extended periodshe JILA team operated the system for up to 28 hours straight.
Perkins explains. his technology excites me because it opens the door to measuring the tiniest protein motions,
#Influential Interfaces Lead to Advances in Organic Spintronics Spintronics is an emerging field of electronics in
in addition to their elementary electric charge. Just as conventional transistors have a source of electrons, a gate to control their movement,
and a drain to carry off the charge signal, a spintronic circuit needs a well-controlled source of spin-polarized electrons that are injected into a transport channel material,
a well-defined method of controlling the spin through the material, and a system to detect the spin signal.
Additionally it requires a transport channel material with long spin lifetimes because (polarized) spins fade away (i e.,
, become randomized) and lose their information during transport, unlike electric charges. Compared to manipulating populations of moving electrons through a conventional semiconductor,
controlling electron spins consumes much less energy and has the further advantage that its information content is on-volatile
because the information is moved and stored in the form of magnetic states, it doesn disappear
when the electricity is turned off. Spintronic devices made of inorganic materials are used today for read heads on hard disk drives
magnetoresistive random access memory (MRAM), and other applications. But recently there is growing worldwide interest in the use of organic materials,
which offer numerous potential benefits: Spin-polarized electrons are predicted to have long lifetimes in organic semiconductors;
Spin-based devices integrated with organic materials are expected to have low fabrication costs, light weight, and mechanical flexibility;
and controlling the interface formation between molecular semiconductors and ferromagnets are important to the development of organic spintronics
because the interface plays a critical role in determining the efficiency of spin injection and detection.
Scientists from PML Semiconductor and Dimensional Metrology Division have performed studies on the way the interface between a ferromagnetic material (cobalt)
and an organic semiconductor known as Alq3 can be altered by coating the cobalt with a single-molecule thick layer (monolayer) that affects the electron spin states of the cobalt.
Cobalt is one of most widely used materials for spin injection/detection and so is Alq3 for spin transport.
Project Leader Christina Hacker elaborates: obalt surfaces are really interesting for electronic applications. If we can place molecular layers on them,
which to attach a monolayer. In the first of two separate, but complementary studies, 2 Hacker team studied the effects of adding a self-assembled monolayer (SAM) 3 to both a pure cobalt surface
and a cobalt surface that was allowed to oxidize. The SAMS studied were octadecanethiol (ODT) and mercaptohexadecanoic acid (MHA.
The data suggest that the MHA monolayer actually etched away much of the oxidized layer from the cobalt,
which is critical in electronic transport through the SAM and into the organic semiconductor. This finding suggests that the rapid oxidation of cobalt does not necessarily have to be a limiting factor in organic spintronics.
In the second study 4 the same molecular layers and the same substrate (cobalt, this time non-oxidized) were stacked onto a layer of Alq3.
and energy band alignment of the materials differently depending on the SAM being studied. In a critical finding, the data imply that the SAMS reduced the molecular hybridization between Co and Alq3,
and, furthermore, enhanced the spin magnetic moment of Co at the interface which is expected to improve spin polarization at the point of spin injection into an organic semiconductor,
Alq3. Hyuk-Jae Jang, the leader of this study, explains the significance: he interface between two different materials is very important in determining the performance and efficiency of electronic devices.
By manipulating the interface between cobalt and Alq3, we show that there are a lot of things we can do to tune the spintronic characteristics of the organic-based device.
Particularly from the XMCD measurements, we found that the spin polarization can be enhanced at the interface by simple interface engineering.
This is helpful in efficient injection of the spin-polarized charge carrier from ferromagnetic materials to organic materials.
The current work is part of a long-term effort to understand how adjusting the composition of an interface with organic semiconductor materials can control spintronic properties. or a complete spintronic device
we need spin injection, spin transport, and spin detection, Jang explains. ur latest work with SAMS only concerns the interface relevant to the spin injection part.
The next step should be to find a better medium for spin transport since only short-distance couple of hundred nanometersf spin transport has been demonstrated in organic materials such as Alq3 so far.
over a micrometer) spin transport through an organic semiconductor. r
#Expert: Editing stem cell genes will evolutionizebiomedical research Applying a dramatically improved method for ditinggenes to human stem cells,
University of Wisconsin-Madison neuroscientist Su-Chun Zhang has shown a new way to silence genes in stem cells and their progeny at any stage of development.
The advance has speed advantages in and efficiency, says Zhang, and is already being used for basic biological studies.
The invention of gene nock-outsarned the 2007 Nobel prize for its utility in determining what genes do.
His work is published in the July 2 edition of Cell Stem Cell. iming is the critical advance,
To produce a knockout mouse, researchers must crossbreed animals after one strand of the gene is gone,
That takes a lot of work, and since cells cannot mate, the technique fails for stem cells.
Alternative techniques were so tedious and inefficient hat it is not worthwhile doing the work,
While the traditional homologous recombination gene editing can only transform a tiny fraction of human cells, CRISPR works in about 50 percent of stem cells,
The fifth column is implanted an bit of genetic code that sits idle until a certain drug enters the cell.
Zhang and postdoctoral researcher Yuejun Chen attached brackets to a gene known to separate the midbrain from the forebrain, the site of higher mental functions.
or to treat disease. Genes that regulate cell division, for example, are often overactive in cancer; gene editing could silence these genes to stop a cancer.
Clinicians worry that transplanting stem cells to heal diabetes or Parkinson disease raises the risk of endless cell divisions and cancer.
Removing genes that promote cell division could forestall that danger. Long before those uses reach the clinic,
however, gene editing will be used to probe the role of genes, Zhang says. e engineer one cell,
and then we expand a large number of cells, and all the offspring have engineered the same ability to delete on demand.
You can very quickly pin down exactly what this gene does, at the stem cell stage, neural stem cell stage or at the differentiated neuron stage.
UW-Madison has opened a genome editing facility in its Biotechnology Center. e want the whole campus to utilize this technology,
for human biology and the model organisms that are so important for biology, like fruit flies and zebra fish,
This marriage between human stem cells and genome editing technology will revolutionize the way we do science.
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