#Atomic force microscope advance leads to new breast cancer research (Nanowerk News) Researchers who developed a high-speed form of atomic force microscopy have shown how to image the physical properties of live breast cancer cells,
said Arvind Raman, Purdue University's Robert V. Adams Professor of Mechanical engineering. In atomic force microscopy (AFM), a tiny vibrating probe called a cantilever passes over a material
There is evidence based on this work and our previous findings that there might be a mechanical signature to drug resistance.
Advanced models allow researchers to convert AFM data into properties about the cells internal scaffolding,
including the motion of fibers called actin. This sequence of atomic force microscope (AFM) images shows before and after effects of inhibiting the function of a key protein in breast cancer cells.
a biochemical process that can alter enzymes and plays a significant role in a wide range of cellular processes.
said Robert L. Geahlen, Distinguished Professor of Medicinal Chemistry at Purdue. We were able to show the turn off of this kinase very rapidly alters the physical properties of the cell.
The paper was authored by former doctoral student Alexander X. Cartagena-Rivera, now a postdoctoral fellow at the National institutes of health's National Institute on Deafness and Other Communication Disorders (NIDCD;
who is affiliated with the Purdue Center for Cancer Research. And thats one of the reasons we were looking at this particular type of cancer cell with this particular form of Syk in it.
One goal of the research is to correlate physical properties of cells with tumor suppression and the action of the kinase on the cell.
and models convert the data to reveal information about the materials composition. Previous applications of AFM microscopy to study live cells provided feedback on the amplitude and frequency of the vibrating cantilever,
#Chitosan coated, chemotherapy packed nanoparticles may target cancer stem cells (Nanowerk News) Nanoparticles packed with a clinically used chemotherapy drug
and kill cancer stem-like cells, according to a recent study led by researchers at The Ohio State university Comprehensive Cancer Center-Arthur G. James Cancer Hospital
and Richard J. Solove Research Institute (OSUCCC-James). Cancer stem-like cells have characteristics of stem cells
and are present in very low numbers in tumors. They are highly resistant to chemotherapy
and radiation and are believed to play an important role in tumor recurrence. This laboratory and animal study showed that nanoparticles coated with the oligosaccharide called chitosan
and encapsulating the chemotherapy drug doxorubicin can target and kill cancer stem-like cells six times more effectively than free doxorubicin.
The study is reported in the journal ACS Nano("Chitosan-Decorated Doxorubicin-Encapsulated Nanoparticle Targets and Eliminates Tumor Reinitiating Cancer Stem-like Cells").
""Our findings indicate that this nanoparticle delivery system increases the cytotoxicity of doxorubicin with no evidence of systemic toxic side effects in our animal model,
"says principal investigator Xiaoming (Shawn) He, Phd, associate professor of Biomedical engineering and a member of the OSUCCC-James Translational Therapeutics Program."
"We believe that chitosan-decorated nanoparticles could also encapsulate other types of chemotherapy and be used to treat many types of cancer."
"This study showed that chitosan binds with a receptor on cancer stem-like cells called CD44,
enabling the nanoparticles to target the malignant stem-like cells in a tumor. The nanoparticles were engineered to shrink,
break open, and release the anticancer drug under the acidic conditions of the tumor microenvironment and in tumor-cell endosomes and lysosomes,
which cells use to digest nutrients acquired from their microenvironment. He and his colleagues conducted the study using models called 3d mammary tumor spheroids (i e.,
, mammospheres) and an animal model of human breast cancer. The study also found that although the drug-carrying nanoparticles could bind to the variant CD44 receptors on cancerous mammosphere cells,
they did not bind well to the CD44 receptors that were overexpressed on noncancerous stem cells s
#Fuel and chemicals from steel plant exhaust gases (Nanowerk News) Carbon monoxide-rich exhaust gases from steel plants are only being reclaimed to a minor extent as power or heat.
Fraunhofer researchers have developed a new recycling process for this materially unused carbon resource: They successfully produced fuel and specialty chemicals from these exhaust gases on a laboratory scale.
Fraunhofer is producing alcohol and acetone at its fermentation facilities, using the synthesized gas from the steel plants.
Fuels and specialty chemicals can be procured from these. Image: Fraunhofer IME) The exhaust gas masses that arise from steel manufacturing plants are gigantic:
the chimneys of the Duisburg Stahlwerke alone unleash several million tons of carbon dioxide. Fraunhofer has developed a process by
which these exhaust fumes can be reclaimed and recycled into fuels and specialty chemicals. With the aid of genetically modified bacterial strains, the research team ferments the gas into alcohols and acetone, convert both substances catalytically into a kind of intermediary diesel product,
and from this they produce kerosene and special chemicals. Participants include the Fraunhofer Institute for Molecular biology and Applied Ecology IME in Aachen,
as well as the Institute for Environment, Safety, and Energy technology UMSICHT in Oberhausen and the Institute for Chemical Technology ICT in Pfinztal.
The technology came about during one of Fraunhofers internal preliminary research projects and through individual projects with industrial partners.
The patented process currently operates on the laboratory scale. Business model instead of problem From our viewpoint, the quantities of carbon alone which rise as smoke from the Duisburg steelworks as carbon dioxide would suffice to cover the entire need for kerosene of a major airline.
Of course, we still have got a bit to go to reach this vision. But we have demonstrated on the laboratory scale that this concept works
and could be of interest commercially. In addition to the exhaust gases, syngas similar gas mixtures from home and industrial waste incineration can also be used for the engineered process
explains Stefan Jennewein of IME, who is coordinating the project. The biochemists at IME use syngas a mixture of carbon monoxide, carbon dioxide and hydrogen as a carbon resource for fermentation.
Using bacterial strains of the Clostridium species, the syngas transforms either into short-chain alcohols like butanol and hexanol,
or into acetone. To do so, IME engineered new genetic processes for the efficient integration of large gene clusters in the Clostridium genome.
At the same time, Fraunhofer further expanded its syngas fermentation system and used it for experiments with the steel and chemicals industry.
The chemists around Axel Kraft at UMSICHT evaporate the residual fermentation products and in a continuous catalytic process
couple the fermentation molecules into an intermediate product consisting of long-chain alcohols and ketones.
This interim product already meets the standards for ship diesel, and, like fats and oils, can be converted through hydrogenation into diesel fuel for cars or kerosene for planes.
Kristian Kowollik from the environmental engineering department at ICT obtains specialty chemicals from the interim product connected with this,
which already can now directly replace petroleum-based products. For example, amines can be used in the pharmaceutical industry or the production of tensides and dying agents.
The products synthetically produced by us can be used both as fuels as well as speciality chemicals. Exactly like this has worked until now with petroleum as the raw material source
states Jennewein. In the next stage, the scientists strive to demonstrate that their technology also works with large quantities.
Over the next one-and-a-half years, we aim at gaining a better understanding of the processes,
For vehicle diesel, that takes about one year, and for kerosene about three years, Axel Kraft adds s
nighttime conversion (Nanowerk News) A University of Texas at Arlington materials science and engineering team has developed a new energy cell that can store large-scale solar energy even
The innovation is an advancement over the most common solar energy systems that rely on using sunlight immediately as a power source.
an assistant professor in the Materials science and engineering Department who led the research team.""As renewable energy becomes more prevalent,
the ability to store solar energy and use it as a renewable alternative provides a sustainable solution to the problem of energy shortage.
It also can effectively harness the inexhaustible energy from the sun."Dong Liu (left), Zi Wei (center) and Fuqiang Liu, an assistant professor in the UT Arlington Materials science and engineering Department.
The work is a product of the 2013 National Science Foundation $400, 000 Faculty Early Career development grant awarded to Liu to improve the way solar energy is captured,
stored and transmitted for use. Other members of the team included lead author Dong Liu
Synergy between Vanadium Redox and Hybrid Photocatalyst",in the most recent edition of the American Chemical Society journal ACS Catalysis. Khosrow Behbehani, dean of the College of Engineering, said the groundbreaking research has the potential
and consume energy.""Dr. Liu and his colleagues are working to help us shape a more sustainable future
and use one of the larger sources of energy available to us-the sun, "Behbehani said.
said a major drawback of current solar technology is the limitation on storing energy under dark conditions."
#Discovery of nanotubes offers new clues about cell-to-cell communication When it comes to communicating with each other,
Certain types of stem cells use microscopic, threadlike nanotubes to communicate with neighboring cells, like a landline phone connection, rather than sending a broadcast signal,
researchers at University of Michigan Life sciences Institute and University of Texas Southwestern Medical center have discovered. The findings,
which are scheduled for online publication July 1 in Nature, offer new insights on how stem cells retain their identities
a U-M developmental biologist whose lab is located at the Life sciences Institute.""There are trillions of cells in the human body,
"The nanotubes had actually been hiding in plain sight. The investigation began when a postdoctoral researcher in Yamashita's lab,
"Niches create a supportive environment for stem cells and help direct their activity. Yamashita, a Howard hughes medical institute investigator, Macarthur Fellow and an associate professor at the U-M Medical school, looked through her old image files
and discovered that the connections appeared in numerous images.""I had seen them, but I wasn't seeing them,
Until the discovery of the nanotubes, scientists had been puzzled as to how cellular signals guiding identity could act on one of the cells
but not the other, said collaborator Michael Buszczak, an associate professor of molecular biology at UT Southwestern,
The researchers conducted experiments that showed disruption of nanotube formation compromised the ability of the germ line stem cells to renew themselves s
#Better memory with faster lasers DVDS and Blu-ray disks contain so-called phase-change materials that morph from one atomic state to another after being struck with pulses of laser light, with data"recorded"in those two atomic states.
Using ultrafast laser pulses that speed up the data recording process, Caltech researchers adopted a novel technique, ultrafast electron crystallography (UEC),
to visualize directly in four dimensions the changing atomic configurations of the materials undergoing the phase changes.
In doing so, they discovered a previously unknown intermediate atomic statene that may represent an unavoidable limit to data recording speeds.
By shedding light on the fundamental physical processes involved in data storage the work may lead to better, faster computer memory systems with larger storage capacity.
The research, done in the laboratory of Ahmed Zewail, Linus Pauling Professor of Chemistry and professor of physics, will be published in the July 28 print issue of the journal ACS Nano("Transient Structures and Possible Limits of Data
Recording in Phase-change Materials"."When the laser light interacts with a phase-change material, its atomic structure changes from an ordered crystalline arrangement to a more disordered,
These two states represent 0s and 1s of digital data.""Today, nanosecond lasersasers that pulse light at one-billionth of a secondre used to record information on DVDS and Blu-ray disks,
by driving the material from one state to another, "explains Giovanni Vanacore, a postdoctoral scholar and an author on the study.
The speed with which data can be recorded is determined both by the speed of the laserhat is,
by the duration of each"pulse"of lightnd by how fast the material itself can shift from one state to the other.
one 0 or 1, every nanosecond,"says Jianbo Hu, a postdoctoral scholar and the first author of the paper."
"To study this, the researchers used their technique, ultrafast electron crystallography. The technique, a new developmentifferent from Zewail's Nobel Prizeinning work in femtochemistry, the visual study of chemical processes occurring at femtosecond scalesllowed researchers to observe directly the transitioning atomic configuration of a prototypical phase-change material
, germanium telluride (Gete), when it is hit by a femtosecond laser pulse. In UEC, a sample of crystalline Gete is bombarded with a femtosecond laser pulse,
the researchers believe that it represents a physical limit to how quickly the overall transition can occurnd to how fast data can be recorded,
"Despite revealing such limits, the research could one day aid the development of better data storage for computers,
Right now, computers generally store information in several ways, among them the well-known random-access memory (RAM) and read-only memory (ROM.
RAM, which is used to run the programs on your computer, can record and rewrite information very quickly via an electrical current.
whenever the computer is powered down. ROM storage, including CDS and DVDS, uses phase-change materials and lasers to store information.
Although ROM records and reads data more slowly, the information can be stored for decades. Finding ways to speed up the recording process of phase-change materials
and understanding the limits to this speed could lead to a new type of memory that harnesses the best of both worlds.
and then rewrite a DVD. Although these applications could mean exciting changes for future computer technologies,
this work is also very important from a fundamental point of view, Zewail says.""Understanding the fundamental behavior of materials transformation is
#New lithium ion battery is safer, tougher, and more powerful Lithium ion batteries (LIBS) are a huge technological advancement from lead acid batteries
which have existed since the late 1850. Thanks to their low weight, high energy density and slower loss of charge when not in use, LIBS have become the preferred choice for consumer electronics.
Lithium-ion cells with cobalt cathodes hold twice the energy of a nickel-based battery and four times that of lead acid.
Despite being a superior consumer battery, LIBS still have some drawbacks. Current manufacturing technology is reaching the theoretical energy density limit for LIBS
and overheating leading to thermal runaway i e. enting with flameis a serious concern. South korean researchers at the Center for Self-assembly and Complexity, Institute for Basic Science (IBS), Department of chemistry and Division of Advanced Materials science at Pohang University, have created a new LIB made from a porous solid
which greatly improves its performance as well as reducing the risks due to overheating("Solid lithium electrolytes based on an organic molecular porous solid").
"Since 2002 there have been over 40 recalls in the US alone due to fire or explosion risk from LIBS used in consumer electronic devices.
These types of batteries, in all of their different lithium-anode combinations, continue to be an essential part of modern consumer electronics
despite their poor track record at high temperatures. The Korean team tried a totally new approach in making the batteries.
According to Dr. Kimoon Kim at IBS, e have investigated already high and highly anisotropic directionally dependent proton conducting behaviors in porous CB 6 for fuel cell electrolytes.
It is possible for this lithium ion conduction following porous CB 6 to be safer than existing solid lithium electrolyte-based organic-molecular porous-materials utilizing the simple soaking method
Current LIB technology relies on intercalated lithium which functions well, but due to ever increasing demands from electronic devices to be lighter and more powerful,
investigation of novel electrolytes is necessary in order. The new battery is built from pumpkin-shaped molecules called cucurbit 6 uril (CB 6)
which are organized in a honeycomb-like structure. The molecules have an incredibly thin 1d-channel,
only averaging 7. 5 Å a single lithium ion is 0. 76 Å, or. 76 x 10-10 m that runs through them.
The physical structure of the porous CB 6 enables the lithium ions to battery to diffuse more freely than in conventional LIBS
and exist without the separators found in other batteries. In tests the porous CB 6 solid electrolytes showed impressive lithium ion conductivity.
To compare this to existing battery electrolytes, the team used a measurement of the lithium transference number (tli)
+which was recorded at 0. 7-0. 8 compared to 0. 2-0. 5 of existing electrolytes.
They also subjected the batteries to extreme temperatures of up to 373 K (99.85°C), well above the 80°C typical upper temperature window for exiting LIBS.
In the tests, the batteries were cycled at temperatures between 298 K and 373 K (24.85°C and 99.85°C) for a duration of four days and after each cycle the results showed no thermal runaway and hardly any change in conductivity.
Various conventional liquid electrolytes can incorporate in a porous CB 6 framework and converted to safer solid lithium electrolytes.
Additionally, electrolyte usage is limited not to use only in LIBS, but a lithium air battery potentially feasible.
What makes this new technique most exciting is that it is a new method of preparing a solid lithium electrolyte
which starts as a liquid but no post-synthetic modification or chemical treatment is needed t
#Visualizing RNAI at work University of Tokyo and Kyoto University researchers have revealed the molecular mechanism of RNA interference (RNAI), the phenomenon by
which the synthesis of a specific protein is inhibited, by real time observation of target RNA cleavage at the single-molecule level.
The phenomenon of RNAI is expected to find applications in medical treatments. RNAI is mediated by RNA-induced silencing complex (RISC),
which contains a small RNA and an Argonaute protein at its core and cleaves the target RNA.
However, there were no suitable tools to directly monitor the RNAI reaction and its molecular mechanism by which RISC cleaves the target RNA has remained unclear.
Now a research group at the University of Tokyo (Professor Takuya Ueda, Professor Yukihide Tomari, Researcher Chunyan Yao and Research Associate Hiroshi M Sasaki,)
and at Kyoto University (Researcher Hisashi Tadakuma), has developed a single-molecule imaging assay for observing target RNA cleavage by RISC in a test tube in real time for the first time,
showing how RISC accurately cleaves and releases targets. Specifically, their obsercations provide direct evidence for the model that the small RNA in the RISC consists of two parts, one
of which quickly binds to the target RNA to be cleaved, while the other proofreads that the correct RNA has been found.
This groundbreaking result reveals RISC molecular mechanism of action and the illustration of this process was adopted as the cover design of this issue of the journal.
This achievement will also contribute to accelerating the research applications of RNAI such as to the development of RNA-based next-generation drugs,
for example as gene therapy to suppress the production of a disease-causing protein n
#Photonic crystal fibre: a multipurpose sensor Glass fibres can do more than transport data. A special type of glass fibre can also be used as a high-precision multipurpose sensor,
as researchers at the Max Planck Institute for the Science of Light (MPL) in Erlangen have demonstrated now("Flying particle sensors in hollow-core photonic crystal fibre").
"The MPL researchers sent a tiny glass bead which can literally sense different physical quantities such as electric field, temperature or vibrations through the inside of this hollow-core photonic crystal fibre.
The flying particle detects the quantities to be measured over long distances with a high spatial resolution, even under harsh conditions like those in an aggressive chemical substance or inside an oil pipeline.
Measured in flight: Researchers at the Max Planck Institute for the Science of Light use a microbead
which flies through the hollow channel in the interior of a photonic crystal fibre to measure different physical quantities, for example the electric field along the optical fibre.
and size of electrodes, represented by copper-coloured plates above and below the fibre, when they are only 200 micrometres wide.
In the beginning, the idea was to develop a radioactivity sensor for inside a nuclear power station says Tijmen Euser from the Max Planck Institute in Erlangen.
Similar tasks are undertaken often using glass fibres with embedded fibre-optic sensors. What is measured is how the light sent through the fibre is affected by an external factor.
Such a fibre-optic sensor can also be used to measure a physical quantity remotely. By wrapping the fibre around the reactor,
fibre-optic sensors could probe the entire surface of a reactor. It turns out, however, that radioactive radiation darkens the interior of conventional glass fibres
so that light can no longer propagate therein, making them unsuitable to measure radioactivity. The glass fibres which we owe particular thanks to for high rates of data transmission
and thus a fast Internet, have an inner channel made of glass with a high refractive index, surrounded by a cladding of glass with a low refractive index.
The difference in refractive index ensures that the light beam is reflected at the interface to the cladding.
It thus remains trapped in the core like water in a pipe and follows the glass fibre,
even if it is curved. Two laser beams manoeuvre a microbead through a hollow glass fibre In photonic crystal fibres (PCFS),
More precisely, they trap light in the inner channel similar to the different types of glass in conventional optical fibres.
however, enable several applications that are not possible with conventional optical fibres. The fact that the fibres have a hollow core was a crucial aspect for the team.
As the air-filled cavity cannot be darkened by radioactive radiation the researchers see PCFS as an interesting alternative to conventional fibre-optic sensors in order to ultimately measure radioactivity as well.
The Erlangen-based physicists examined whether hollow-core photonic crystal fibres are suitable as sensors by initially using the fibres to measure electric fields, vibrations and temperatures.
To this effect, they used a tiny glass bead as the measuring probe and guided it through the thin,
Less light passes through the fibre in a strong electric field To measure the strength of an electric field,
In an electric field it is deflected therefore from the centre of the channel to its edge,
The loss here is proportional to the strength of the electric field, and it is thus possible to determine the field from a distance.
the researchers passed the glass fibre close to very fine electrodes, the thinnest measuring a mere 200 micrometers (one micrometre corresponds to one thousandth of a millimetre.
The researchers actually succeeded in accurately reproducing the fine structure of the electrodes with their fibre-optic measuring instrument.
We were also able to measure magnetic fields with a magnetic bead with extremely high precision,
doctoral student at the Max Planck Institute in Erlangen and lead author of the study. Vibrations could also be determined similarly,
Electric fields and vibrations can be distinguished by the behaviour of beads carrying different levels of charge.
which is familiar from passing cars. Their sound has a higher pitch when they are approaching than
Fluorescent beads as a sensor for radioactivity In their experiment the researchers used an oven to heat part of the fibre to temperatures of several hundred degrees Celsius.
Next, we want to realize the radioactivity sensor, says Bykov. To do this, the researchers want to use fluorescent beads
Nanoparticles would then make it possible to measure with nanometre accuracy, i e. on the scale of viruses. The maximum length of the sensor fibre is currently around 400 metres,
as the laser light experiences losses as it is transmitted in the PCF, and thus the glass bead can no longer be trapped above a certain length.
These could be used to increase the range of the fibre sensors to several tens of kilometres.
The sensors could also be useful along high voltage lines or in transformer substations. Electric fields
vibrations and temperatures, and thus three quantities that are relevant in these installations, could be recorded with a single measuring instrument t
#'Invisible'protein structure explains the power of enzymes A research group at Ume University in Sweden has managed to capture
The discovery lays the base for developing designed enzymes as catalysts to new chemical reactions for instance in biotechnological applications.
The result of the study is published in the journal Nature Communications("Structural basis for catalytically restrictive dynamics of a high-energy enzyme state".
This increase of speed is completely necessary for all biological life, which would otherwise be limited by the slow nature of vital chemical reactions.
So-called high-energy states in enzymes are regarded as necessary for catalysing of chemical reactions. A high-energy level is a protein structure only occurring temporarily and for a short period of time;
and these factors collaborate until its state becomes invisible to traditional spectroscopic techniques. The Ume researchers have managed to find a way to maintain a high-energy state in the enzyme, adenylate kinase,
by mutating the protein.""Thanks to this enrichment, we have been able to study both structure and dynamics of this state.
The study shows that enzymatic high-energy states are necessary for chemical catalysis, "says Magnus Wolf-Watz, research group leader at the Department of chemistry.
"Research on Bioenergy is an active field at Ume University. An important, practical application of the new knowledge can be enzymatic digestion of useful molecules from wooden raw materials,
Nuclear Magnetic resonance (NMR) and x-ray crystallography being the main techniques.""One of the strengths of Ume University is the open cooperative climate with low or no barriers between research groups.
It means that exciting research can be conducted in the borderland of differing expertise, "says Magnus Wolf-Watz z
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