#Scientists use nanotechnology to visualize potential brain cancer treatments in real time (Nanowerk News) Virginia Tech Carilion Research Institute scientists have developed new imaging techniques to watch dangerous brain tumor
Published in NANO Letters("Real-time Visualization of Nanoparticles Interacting with Glioblastoma Stem Cells), "the study was led by Zhi Sheng and Deborah Kelly, both assistant professors at the institute,
and describes how the research team used nanotechnology to watch tumor stem cells respond to therapy. ee never been able to directly observe the actions of potential cancer treatments this way before,
said Sheng, a cancer biologist and an assistant professor of biomedical sciences and pathobiology at the Virginiaaryland College of Veterinary medicine. t was astounding.
In all my years of researching glioblastoma, I had seen only static images. Both Sheng and Kelly credit Elliot Pohlmann, a fourth-year Virginia Tech School of medicine student and the paper first author, for sparking the collaboration between their laboratories on this particular project. e realized that glioblastoma
stem cells could work very well with the imaging techniques Dr. Kelly was said developing, Pohlmann. ith a little trial and error, wee produced visually striking images.
Glioblastoma is a brain cancer with a poor prognosis. Even with surgical interventions or traditional treatments
some of the cells the stem cells tend to survive and grow new tumors. lioblastoma tumors are hard to target,
Sheng said. heye aggressive and resistant to therapeutics. With our imaging techniques, we may be able to gain new insights into how the cells dynamically respond to treatments.
The research team separated the hard-to-kill stem cells from the general glioblastoma population by attracting the stem cells to a microchip coated with antibodies.
The scientists then used a specially designed microfluidic chamber to trap the cells in a liquid environment.
Once the samples were in place the scientists blasted them with gold nanorods similar to what is used in some cancer treatments
and watched the process in cell cultures using in situ transmission electron microscopy. Kelly partnered with coauthor Madeline Dukes, an applications scientist at Protochips Inc,
. to develop the microfluidic equipment. e were curious to see whether we could isolate these types of toxic cells from the other brain tumor cells,
while developing new imaging tools at the single-cell level to visualize the course of therapies needed to eradicate these cells,
said Kelly, the project lead scientist and a biophysicist with extensive expertise in high-resolution imaging.
She is also an assistant professor of biological sciences In virginia Tech College of Science. t exciting to see things no one else has seen before,
Pohlmann said. t even more exciting to produce the profound images with this project. Researchers say the technology has many potential applications. ne may be able to directly observe an influenza virus, HIV,
or other human pathogens infecting a cell, or even test new cancer treatments at the cellular level, Kelly said.
Sheng pointed to another characteristic that makes cancer cells difficult to treat: broad heterogeneity. In the same cancer population, even neighboring cells can differ drastically,
and each cell can respond to treatments differently. e can look at single-cell delivery of cancer treatments,
and see how the individual cells respond, Sheng said. f we can learn how to kill these cells,
we should be able to improve our chances of developing effective treatments by being able to directly observe the effects of the possible therapeutics. e
#Electrical control of quantum bits in silicon paves the way to large quantum computers (Nanowerk News) A University of New south wales (UNSW)- led research team has encoded quantum information in silicon using simple electrical pulses for the first time,
bringing the construction of affordable large-scale quantum computers one step closer to reality. Lead researcher, UNSW Associate professor Andrea Morello from the School of Electrical engineering and Telecommunications, said his team had realised successfully a new control method for future quantum computers.
The findings were published today in the open-access journal Science Advances("Electrically controlling single-spin qubits in a continuous microwave field".
"This is an electron wave in a phosphorus atom, distorted by a local electric field. Unlike conventional computers that store data on transistors and hard drives, quantum computers encode data in the quantum states of microscopic objects called qubits.
The UNSW team, which is affiliated with the ARC Centre of Excellence for Quantum Computation & Communication Technology, was first in the world to demonstrate single-atom spin qubits in silicon,
reported in Nature in 2012 and 2013. The team has improved already the control of these qubits to an accuracy of above 99%and established the world record for how long quantum information can be stored in the solid state
as published in Nature Nanotechnology in 2014. It has demonstrated now a key step that had remained elusive since 1998."
"We demonstrated that a highly coherent qubit, like the spin of a single phosphorus atom in isotopically enriched silicon,
can be controlled using electric fields, instead of using pulses of oscillating magnetic fields, "explained UNSW's Dr Arne Laucht,
postdoctoral researcher and lead author of the study. Associate professor Morello said the method works by distorting the shape of the electron cloud attached to the atom,
using a very localized electric field.""This distortion at the atomic level has the effect of modifying the frequency at
which the electron responds.""Therefore, we can selectively choose which qubit to operate. It's a bit like selecting which radio station we tune to,
by turning a simple knob. Here, the'knob'is applied the voltage to a small electrode placed above the atom."
"The findings suggest that it would be possible to locally control individual qubits with electric fields in a large-scale quantum computer using only inexpensive voltage generators, rather than the expensive high-frequency microwave sources.
Moreover, this specific type of quantum bit can be manufactured using a similar technology to that employed for the production of everyday computers,
drastically reducing the time and cost of development. The device used in this experiment was fabricated at the NSW node of the Australian National Fabrication Facility,
in collaboration with the group led by UNSW Scientia Professor Andrew Dzurak. Key to the success of this electrical control method is the placement of the qubits inside a thin layer of specially purified silicon
"Associate professor Morello said. The purified silicon was provided through collaboration with Professor Kohei Itoh from Keio University in Japan n
#Performance and durability combine in liquid crystal transistors (Nanowerk News) Crystalline organic semiconductors have attracted a lot of interest for convenient low-cost fabrication by printed electronics.
However progress has been stymied by the low thermal durability and reproducibility of these materials. Now researchers at Tokyo Institute of technology and the Japan Science and Technology Agency have designed a liquid crystal molecule that produces high-performance organic field effect transistors (FETS) with good temperature resilience and relatively low device
variability in addition to high mobility("Liquid crystals for organic thin-film transistors"."Hiroaki Iino, Takayuki Usui and Jun-ichi Hanna designed a molecule that would incorporate a number of desirable liquid crystal qualities, in particular the smectic E phase.
Low ordered liquid crystal phases form droplets at their melting temperature, but the smectic E phase has the advantage of retaining the thin-film shape.
Using atomic force microscopy the researchers identified that at around 120 C in the crystal formed a bilayer crystal phase.
"Considering that it could potentially be necessary to fabricate millions of FETS for display applications,
"point out the researchers in a report of the work. The devices also exhibited a minimal variability of just 1. 22v-1s-1,
resulting from the phase transition from a monolayer to a bilayer crystal structure in mono-alkylated liquid crystalline molecules may lead to the possibility of designing new materials for the burgeoning field of printed electronics."
and single-crystal structures of the ac (middle) and ab planes (bottom). Right: Output characteristics of FETS fabricated using the polycrystalline thin films as-coated (top)
Background Small-molecule versus polymer FETS The main issues around organic semiconductor FETS with small molecules are the low thermal durability.
The same bonding that makes the molecules soluble for printing fabrication processes also leaves them prone to low melting points,
Attempts to use polymers with benzene-like delocalised electron bonding alleviated issues around the thermal durability to a certain extent.
such as reproducible synthesis and purification of the polymers, as well as control of crystallinity and the molecular orientations towards both the substrate surface and the electrodes.
The design of the molecule The researchers identified specific characteristics to enrol in the design of their molecule.
The phase transition Studies of the field effect transistors before and after mild annealing revealed an improvement in carrier mobility by over an order of magnitude.
and 120 C. Improvements in device performance plateaued above 120 C. Atomic force microscope studies of the materials identified a step structure that changed from monolayer 2. 8 nm steps to bilayer 5
the researchers concluded that crystal-to-crystal phase change from a monolayer to a bilayer structure was improved responsible for the transistor performance in annealed devices s
#New ways to see light and store information (Nanowerk News) Reseachers from the University of Cologne,
Jilin University (China) and the University of Nottingham (UK) have developed a method that significantly prolongs the lives of charges in organic electronic devices("Organic Electronics:
Engineering Ultra Long Charge Carrier Lifetimes in Organic Electronic devices at Room temperature"."Silicon based chips and transistors have been at the heart of all electronic devices since the 1950s.
Driven by economic and environmental factors, and by the need for renewable energy resources, there is currently an enormous scientific and technological interest in transitioning away from silicon based electronics to new organic electronic devices.
Just like living organisms, organic electronics use carbon in complex molecules as their key functional component.
These new organic electronic devices are less expensive, more environmentally friendly and better recyclable than the older ones.
Today the most commercially successful organic electronic devices are OLEDS (organic light emitting diodes) found in smart phone displays.
Other promising devices include very inexpensive solar cells for low-cost and low-carbon electricity generation and ultra-efficient building lighting which could substantially lower electricity consumption.
Yajun Gao and Professor Paul H. M. van Loosdrecht from the University of Cologne have made now substantial progress in this field in collaboration with researchers from Jilin University (China) and the University of Nottingham (UK).
) The team was able to design an organic electronic device in which charge generated by light lived approximately 10,000 times longer than was thought previously possible.
They did this by designing a small device based on organic molecules in which the built-in electric field creates a well
which traps and protects charge carriers. This opens up the possibility of creating entirely new classes of organic electronic devices
such as ultra-sensitive photo detectors to image distant stars, or flexible memory elements which could be used in wearable computers s
#'Parachuting'boron on benzene rings (Nanowerk News) Tuning the para position of benzene moieties is significant for creating biologically active compounds and optoelectronic materials.
Yet, attaching a functional handle specifically at the para position of benzene has been challenging due to multiple reactive sites on the ring.
Chemists at ITBM, Nagoya University have developed a novel iridium catalyst that enables highly para-selective borylation on benzene,
leading to the rapid synthesis of drug derivatives for treating Parkinson's disease. Nagoya, Japan-Yutaro Saito, Yasutomo Segawa and Professor Kenichiro Itami at the Institute of Transformative Biomolecules (ITBM
Nagoya University and the JST-ERATO Itami Molecular Nanocarbon Project have developed a bulky iridium catalyst that selectively directs a boron moiety to the opposite side of mono-substituted benzene derivatives.
The opposite side of the benzene ring, known as the para position is important for tuning the electronic
and steric properties of various organic molecules, including biologically active compounds such as pharmaceuticals and agrochemicals,
as well as optoelectronic materials. Nonetheless, few reports have existed in obtaining para-selective benzene derivatives directly from mono-substituted benzene rings.
Using a bulky phosphorus ligand, Itami and his coworkers have generated a new catalyst that uses steric interactions with the benzene substituent,
to achieve the first highly para-selective C-H borylation, i e. replacement of a hydrogen atom at the para position with a boryl moiety.
The boryl group can easily be converted into other functional groups, making it possible to conduct late stage diversification of core structures containing benzene.
The study, published online on April 10, 2015 in the Journal of the American Chemical Society("para-CH Borylation of Benzene derivatives by a Bulky Iridium Catalyst),
"displays the development of a powerful synthetic method that enables rapid access to para-functionalized benzene derivatives to construct libraries of bioactive compounds that are useful in medicinal chemistry.
which is an anticholinergic drug used in the treatment of Parkinson's disease.''Parachuting'boron onto the para-position of a benzene ring by a bulky iridium catalyst.
ITBM, Nagoya University) Metal-catalyzed C-H borylation of aromatic rings is considered an efficient way to introduce functional groups to make functional molecules via a boryl moiety.
Nonetheless, introducing a boryl group at a specific position on the 6-membered benzene ring has been rather challenging due to the presence of several reactive sites.
"As altering the para position has been a common approach in biology and materials science for creating benzene-containing functional molecules,
I figured that para-selective C-H functionalization would be an extremely useful technique for the late-stage diversification of core structures.
However, there has been no general way to do this up to now, "says Kenichiro Itami, the Director of the Institute of Transformative Biomolecules."
"Since starting this research in 2009, we have been trying to find ways to introduce functional groups at the para position of the benzene ring"says Yasutomo Segawa,
a co-author of this work.""Yutaro picked up this work in 2012, and screened over 200 ligands to find the right conditions to achieve C-H borylation in high para-selectivity.""
""I looked at all the ligands that I could find in the labs and after a year and a half of screening,
a graduate student who conducted the experiments.""Nitrogen-based ligands are used usually in C-H aromatic borylation reactions,
Caramiphen, an anticholinergic agent used for the treatment of Parkinson's disease contains a monosubstituted benzene moiety along with ester and amine groups.
"We hope that this reaction would be applicable for making useful para-intermediates that would lead to the rapid discovery and optimization of lead compounds in the pharmaceutical, agrochemical and materials industry
#Harvesting energy from electromagnetic waves (Nanowerk News) For our modern, technologically-advanced society, in which technology has become the solution to a myriad of challenges,
energy is critical not only for growth but also, more importantly, survival. The sun is an abundant and practically infinite source of energy,
so researchers around the world are racing to create novel approaches to"harvest"clean energy from the sun or transfer that energy to other sources.
This week in the journal Applied Physics Letters("Metamaterial electromagnetic energy harvester with near unity efficiency"),researchers from the University of Waterloo in Canada report a novel design for electromagnetic energy harvesting based on
the"full absorption concept.""This involves the use of metamaterials that can be tailored to produce media that neither reflects nor transmits any power--enabling full absorption of incident waves at a specific range of frequencies and polarizations."
"The growing demand for electrical energy around the globe is the main factor driving our research,
"said Thamer Almoneef, a Ph d. student.""More than 80 percent of our energy today comes from burning fossil fuels,
which is both harmful to our environment and unsustainable as well. In our group, we're trying to help solve the energy crisis by improving the efficiency of electromagnetic energy-harvesting systems."
"Since the inception of collecting and harvesting electromagnetic energy, classical dipole patch antennas have been used.""Now, our technology introduces'metasurfaces'that are much better energy collectors than classical antennas,
"explained Omar M. Ramahi, professor of electrical and computer engineering. Metasurfaces are formed by etching the surface of a material with an elegant pattern of periodic shapes.
The particular dimensions of these patterns and their proximity to each other can be tuned to provide"near-unity"energy absorption.
This energy is channeled then to a load through a conducting path that connects the metasurface to a ground plane.
The key significance of the researchers'work is that it demonstrates for the first time that it's possible to collect essentially all of the electromagnetic energy that falls onto a surface."
"Conventional antennas can channel electromagnetic energy to a load --but at much lower energy absorption efficiency levels,"said Ramahi."
"We can also channel the absorbed energy into a load, rather than having the energy dissipate in the material as was done in previous works."
"As you can imagine, this work has a broad range of applications. Among the most important is space solar power,
an emerging critical technology that can significantly help to address energy shortages. It converts solar rays into microwaves--using conventional photovoltaic solar panels--and then beams the microwave's energy to microwave collector farms at designated locations On earth.
Japan is way out in front of rest of the world in this realm, with plans to begin harvesting solar power from space by 2030."
"Our research enables significantly higher energy absorption than classical antennas, "Ramahi said.""This results in a significant reduction of the energy harvesting surface footprint.
Real estate is a precious commodity for energy absorption --whether it's wind, hydro, solar or electromagnetic energy."
"Other key applications include"wireless power transfer--directly adaptable to power remote devices such as RFID devices and tags or even remote devices in general,"Ramahi noted.
The technology can also be extended to the infrared and visible spectra.""We've already extended our work into the infrared frequency regime
and we hope to report very soon about near-unity absorption in those higher-frequency regimes,"added Ramahi i
#Graphene pushes the speed limit of light-to-electricity conversion (Nanowerk News) The efficient conversion of light into electricity plays a crucial role in many technologies,
ranging from cameras to solar cells. It also forms an essential step in data communication applications, since it allows for information carried by light to be converted into electrical information that can be processed in electrical circuits.
Graphene is an excellent material for ultrafast conversion of light to electrical signals, but so far it was known not how fast graphene responds to ultrashort flashes of light.
ICFO researchers Klaas-Jan Tielrooij Lukasz Piatkowski, Mathieu Massicotte and Achim Woessner led by ICFO Prof.
Frank Koppens and ICREA Prof. at ICFO Niek van Hulst, in collaboration with scientists from the research group led by Pablo Jarillo-Herrero at MIT
and the research group led by Jeanie Lau at UC Riverside, have demonstrated now that a graphene-based photodetector converts absorbed light into an electrical voltage at an extremely high speed.
The study, entitled"Generation of photovoltage in graphene on a femtosecond timescale through efficient carrier heating",has recently been published in Nature Nanotechnology("Generation of photovoltage in graphene on a femtosecond timescale through efficient carrier heating".
"The new device that the researchers developed is capable of converting light into electricity in less than 50 femtoseconds (a twentieth of a millionth of a millionth of a second.
To do this, the researchers used a combination of ultrafast pulse-shaped laser excitation and highly sensitive electrical readout.
As Klaas-Jan Tielrooij comments,"the experiment uniquely combined the ultrafast pulse shaping expertise obtained from single molecule ultrafast photonics with the expertise in graphene electronics.
Facilitated by graphene's nonlinear photo-thermoelectric response, these elements enabled the observation of femtosecond photodetection response times."
"The ultrafast creation of a photovoltage in graphene is possible due to the extremely fast and efficient interaction between all conduction band carriers in graphene.
This interaction leads to a rapid creation of an electron distribution with an elevated electron temperature.
Thus, the energy absorbed from light is efficiently and rapidly converted into electron heat. Next, the electron heat is converted into a voltage at the interface of two graphene regions with different doping.
This photo-thermoelectric effect turns out to occur almost instantaneously, thus enabling the ultrafast conversion of absorbed light into electrical signals.
As Prof. van Hulst states""it is amazing how graphene allows direct nonlinear detecting of ultrafast femtosecond (fs) pulses".
"The results obtained from the findings of this work, which has been funded partially by the EC Graphene Flagship,
open a new pathway towards ultra-fast optoelectronic conversion. As Prof. Koppens comments,"Graphene photodetectors keep showing fascinating performances addressing a wide range of applications
#Lanthanide-organic framework nanothermometers prepared by spray-drying A work in Advanced Functional Materials shows how spray-drying prepared MOF nanoparticles containing lanthanide metals may be used as nanothermometers operative over a wide range of temperatures
, in particular, in the cryogenic range. The work was coordinated from the University of Aveiro (Portugal)
and participated by Ramón y Cajal Researcher Dr Inhar Imaz and ICREA Research Prof Daniel Maspoch from the ICN2 Supramolecular Nanochemistry & Materials Group.
Members of the ICN2 have collaborated in a new research to get nanothermometersthat can provide accurate, noninvasive and self-referenced temperature measurements at the submicrometer scale.
Ramón y Cajal Researcher Dr. Inhar Imaz and ICREA Research Prof Daniel Maspoch from the Supramolecular Nanochemistry & Materials Group have participated in the research
which has been coordinated from University of Aveiro (Portugal). The results have been published in Advanced Functional Materials in an article entitled"Lanthaniderganic Framework Nanothermometers Prepared by Spray-Drying".
, biological fl uids, strong electromagnetic fields, and fast-moving objects. The strategy followed to design this kind of devices relies on the thermal dependence of the phosphor luminescence,
biological fluids, strong electromagnetic fields, and fast-moving objects. The temperature determination is usually based on the change of the luminescence intensity or decay times.
However, the measurements based on a single f transition may be affected much by the variation of the sensor concentration and the drift of the optoelectronic systems
namely, the excitation sources and detectors. Recently, authors reported self-reference nanothermometers based on the intensity ratio of two f transitions that overcome the drawbacks of temperature determination with a single transition.
The article also shows that spray-drying prepared MOF nanoparticles may be used as ratiometric luminescent nanothermometers operative over a wide range of temperatures, in particular, in the cryogenic range.
Prof Maspoch and Dr Imaz have contributed in the synthesis of the MOF nanoparticles of Tb (III) and Eu (III),
the first lanthanide-organic framework prepared by the spray-drying method. This system is the most sensitive cryogenic nanothermometer reported so far
#Millions of liters of juice from 1 grapefruit (Nanowerk News) The Austrian Centre of Industrial biotechnology (acib) uses the positive aspects of synthetic biology for the ecofriendly production of a natural compound("Production of the sesquiterpenoid
"The challenge of the biotechnologists Tamara Wriessnegger and Harald Pichler in Graz was to produce Nootkatone in large quantities.
because Nootkatone is used as a high quality, natural flavoring substance in millions of liters of soft and lifestyle drinks,
as a biopharmaceutical component or as a natural insect repellent.""We have installed new genetic information in the yeast Pichia pastoris,
so that our cells are able to produce Nootkatone from sugar, "says acib researcher Tamara Wriessnegger.
The genome of the yeast cells has been extended with four foreign genes derived from the cress Arabidopsis thaliana, the Egyptian henbane Hyoscyamus muticus, the Nootka cypress Xanthocyparis nootkatensis and from baker's yeast Saccharomyces cerevisiae.
With the help of the new genes the yeast is capable to synthesize the high-prized, natural flavor (more than 4000 euros per kilo) in a cheap way and in useful quantities from sugar (one euro per kilo.
As an insecticide it is effective against ticks, mosquitoes or bedbugs. In the medical field, the substance has shown activity against cancer cell lines.
In cosmetics, people appreciate the good smell, in soft drinks a fine, subtle taste. Because the natural sources cannot meet the demands,
the acib method replaces chemical synthesis-an energy-consuming and anything but environmentally friendly process.
The common biotech variant via Valencene and a chemical synthesis step is less ecofriendly, more difficult and expensive.
"Synthetic biology could be of vital importance to humanity, as Artemisinin shows. Thanks to this substance malaria is curable.
Unfortunately, it could be found only in tiny quantities in the sweet wormwood-until the US researcher Jay Keasling was able to transfer the appropriate production route from the plant in bacteria.
#Nature-inspired nanotechnology mesh captures oil but lets water through (Nanowerk News) The unassuming piece of stainless steel mesh in a lab at The Ohio State university doesn't look like a very big deal,
but it could make a big difference for future environmental cleanups. Water passes through the mesh
The mesh coating is among a suite of nature-inspired nanotechnologies under development at Ohio State
superoleophobic coatings prepared by layer-by-layer technique for anti-smudge and oil-water separation"and"Nanomechanical behavior of Mos2 and WS2 multi-walled nanotubes and Carbon nanohorns").
"said Bharat Bhushan, Ohio Eminent Scholar and Howard D. Winbigler Professor of mechanical engineering at Ohio State.
The work was inspired partly by lotus leaves, whose bumpy surfaces naturally repel water but not oil.
Bhushan and postdoctoral researcher Philip Brown chose to cover a bumpy surface with a polymer embedded with molecules of surfactant--the stuff that gives cleaning power to soap and detergent.
They sprayed a fine dusting of silica nanoparticles onto the stainless steel mesh to create a randomly bumpy surface
and layered the polymer and surfactant on top. The silica surfactant, polymer, and stainless steel are all nontoxic
and relatively inexpensive, said Brown. He estimated that a larger mesh net could be created for less than a dollar per square foot.
Because the coating is only a few hundred nanometers (billionths of a meter) thick, it is mostly undetectable.
To the touch, the coated mesh doesn't feel any bumpier than uncoated mesh. The coated mesh is a little less shiny,
though, because the coating is only 70 percent transparent. The researchers chose silica in part
because it is an ingredient in glass, and they wanted to explore this technology's potential for creating smudge-free glass coatings.
At 70 percent transparency the coating could work for certain automotive glass applications, such as mirrors, but not most windows or smartphone surfaces."
"Our goal is to reach a transparency in the 90-percent range, "Bhushan said.""In all our coatings, different combinations of ingredients in the layers yield different properties.
"He explained that certain combinations of layers yield nanoparticles that bind to oil instead of repelling it.
The shape of the nanostructures plays a role, as well. In another project, research assistant Dave Maharaj is investigating
what happens when a surface is made of nanotubes. Rather than silica, he experiments with molybdenum disulfide nanotubes,
which mix well with oil. The nanotubes are approximately a thousand times smaller than a human hair.
Maharaj measured the friction on the surface of the nanotubes and compressed them to test how they would hold up under pressure."
"There are natural defects in the structure of the nanotubes, "he said.""And under high loads, the defects cause the layers of the tubes to peel apart
and create a slippery surface, which greatly reduces friction.""Bhushan envisions that the molybdenum compound's compatibility with oil,
In addition, for micro-and nanoscale devices, commercial oils may be too sticky to allow for their efficient operation.
Here, he suspects that the molybdenum nanotubes alone could be used to reduce friction. This work began more than 10 years ago,
when Bhushan began building and patenting nano-structured coatings that mimic the texture of the lotus leaf.
"We've studied so many natural surfaces, from leaves to butterfly wings and shark skin, to understand how nature solves certain problems,
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