Ion Tiger sets New Endurance Record for Small Electric Unmanned Aerial Vehicles

Fueled by liquid hydrogen (LH2), the Ion Tiger unmanned aerial vehicle (UAV) completes a record flight time of 48 hours and 1 minute. 

The electric fuel cell propulsion system onboard the Ion Tiger has the low noise and signature of a battery-powered UAV, while taking advantage of high-energy hydrogen fuel and the high electric efficiency of fuel cells. 

Credit: Image courtesy of Naval Research Laboratory (NRL)

Researchers at the U.S. Naval Research Laboratory flew their fuel cell powered Ion Tiger UAV for 48 hours and 1 minute on April 16-18 by using liquid hydrogen fuel in a new, NRL-developed, cryogenic fuel storage tank and delivery system.

This flight shatters their previous record of 26 hours and 2 minutes set in 2009 using the same vehicle, but with gaseous hydrogen stored at 5000 psi.

Liquid hydrogen is three times denser than 5000-psi compressed hydrogen. The cryogenic liquid is stored in a lightweight tank, allowing more hydrogen to be carried onboard to increase flight endurance.

Success in flight requires developing a high quality, lightweight insulated flight dewar for the cryogenic fuel, plus matching the boil off of the cryogenic hydrogen to the vehicle fuel consumption.

"Liquid hydrogen coupled with fuel-cell technology has the potential to expand the utility of small unmanned systems by greatly increasing endurance while still affording all the benefits of electric propulsion," said Dr. Karen Swider-Lyons, NRL principal investigator.

Although long endurance is possible with conventional, hydrocarbon-fueled systems, these are usually loud, inefficient, and unreliable in this aircraft class.

Similarly, small, electric, battery-powered systems are limited to endurances of only several hours.

To address the logistics of in-theater supply of liquid or gaseous hydrogen, NRL proposes in-situ manufacture of LH2 for use as fuel.

An electrolyzer-based system would require only water for feedstock, and electricity, possibly from solar or wind, to electrolyze, compress, and refrigerate the fuel.

The NRL LH2 flight capability is being developed by NRL's Tactical Electronic Warfare and Chemistry Divisions, and is sponsored by the Office of Naval Research.

AUTISM: Difficulty in Recognising Faces Linked to Performance in a Group of Neurons

Neuroscientists at Georgetown University Medical Center (GUMC) have discovered a brain anomaly that explains why some people diagnosed with autism cannot easily recognize faces -- a deficit linked to the impairments in social interactions considered to be the hallmark of the disorder.

They also say that the novel neuroimaging analysis technique they developed to arrive at this finding is likely to help link behavioral deficits to differences at the neural level in a range of neurological disorders.

The final manuscript published March 15 in the online journal NeuroImage: Clinical, the scientists say that in the brains of many individuals with autism, neurons in the brain area that processes faces (the fusiform face area, or FFA) are too broadly "tuned" to finely discriminate between facial features of different people.

They made this discovery using a form of functional magnetic resonance imaging (fMRI) that scans output from the blueberry-sized FFA, located behind the right ear.

"When your brain is processing faces, you want neurons to respond selectively so that each is picking up a different aspect of individual faces. The neurons need to be finely tuned to understand what is dissimilar from one face to another," says the study's senior investigator, Maximilian Riesenhuber, PhD., an associate professor of neuroscience at GUMC.

"What we found in our 15 adult participants with autism is that in those with more severe behavioral deficits, the neurons are more broadly tuned, so that one face looks more like another, as compared with the fine tuning seen in the FFA of typical adults," he says.

"And we found evidence that reduced selectivity in FFA neurons corresponded to greater behavioral deficits in everyday face recognition in our participants. This makes sense. If your neurons cannot tell different faces apart, it makes it more difficult to tell who is talking to you or understand the facial expressions that are conveyed, which limits social interaction."

Riesenhuber adds that there is huge variation in the ability of individuals diagnosed with autism to discriminate faces, and that some autistic people have no problem with facial recognition.

"But for those that do have this challenge, it can have substantial ramifications -- some researchers believe deficits in face processing are at the root of social dysfunction in autism," he says.

The neural basis for face processing
Neuroscientists have used traditional fMRI studies in the past to probe the neural bases of behavioral differences in people with autism, but these studies have produced conflicting results, says Riesenhuber.

"The fundamental problem with traditional fMRI techniques is that they can tell which parts of the brain become active during face processing, but they are poor at directly measuring neuronal selectivity," he says, "and it is this neuronal selectivity that predicts face processing performance, as shown in our previous studies."

To test their hypothesis that differences in neuronal selectivity in the FFA are foundational to differences in face processing abilities in autism, Riesenhuber and the study's lead author, neuroscientist Xiong Jiang, PhD, developed a novel brain imaging analysis technique, termed local regional heterogeneity, to estimate neuronal selectivity.

Read the full article here

E.Coli: UCLA Engineers create cell phone-based sensor

Researchers from the UCLA Henry Samueli School of Engineering and Applied Science have developed a new cell phone–based fluorescent imaging and sensing platform that can detect the presence of the bacterium Escherichia coli in food and water.

The engineers combined antibody functionalized glass capillaries with quantum dots (semiconductors often used for medical imaging) as signal reporters to specifically detect E. coli particles in liquid samples using a lightweight, compact attachment to an existing cell-phone camera.

The cost-effective cell-phone attachment acts as a florescent microscope, quantifying the emitted light from each capillary after the specific capture of E. coli particles within a sample.

By quantifying the florescent light emission from each tube, the concentration of E. coli in the sample can be determined.

E. coli can easily contaminate food and drinking water. It poses a significant threat to public health, even in highly developed parts of the world, and causes a large number of hospitalizations and deaths every year.

As few as 10–100 E. coli particles can kill the cells of the intestinal lining, destroy the kidneys and cause blood clots in the brain, as well as seizures, paralysis and respiratory failure.

This study illustrates the promising potential of a cell phone–enabled, field-portable and cost-effective E. coli detection platform for the screening of both water and food samples.

Authors of the research include UCLA electrical engineering postdoctoral scholar Hongying Zhu; UCLA electrical engineering undergraduate student Uzair Sikora; and UCLA associate professor of electrical engineering and bioengineering Aydogan Ozcan. Ozcan is also a member of the California NanoSystems Institute at UCLA.

More information: The research is published in the peer-reviewed journal The Royal Society of Chemistry and is available online at RSC Publishing

White blood cell chasing a bacteria

Malaria: Prevention by Blocking Cell’s Passage

Researchers at the Wellcome Trust Sanger Institute have discovered an understanding on how the most deadly species of malaria parasite, Plasmodium falciparum, invades human red blood cells.

They used the technique called Avidity-based Extracellular Interaction Screen (AVEXIS), which discovered the interaction between the parasite protein and the host receptor.

The parasite relies on a single receptor on the red blood cell's surface to invade, offering an exciting new focus for vaccine development.

The blood stage of Plasmodium's lifecycle begins when the parasite invades human red blood cells, and it is this stage that is responsible for the symptoms and mortality associated with malaria.

"Our research seems to have revealed an Achilles' heel in the way the parasite invades our red blood cells. It is rewarding to see how our techniques can be used to answer important biological problems and lay the foundations for new therapies," senior co-author Gavin Wright said in a statement.

However, researchers demonstrated that disrupting this interaction completely blocked the parasite from gaining entry into the red blood cell. Importantly, this was true across all parasite strains tested, making it appear that the receptor is a universal entry pathway. It is hoped that the parasite's dependency on this one protein can now be exploited to develop new and effective vaccines.

Malaria kills approximately one million people every year, mostly children under the age of five in sub-Saharan Africa. Researchers have tried for many years to develop a vaccine to prevent the parasite gaining entry into our red blood cells, but so far they have been unsuccessful.

One of the challenges is that the parasite is adaptable - although several red blood cell receptors had been previously identified, none was shown to be essential: when entry through one receptor is prevented, the parasite is able to switch to another. This new research has found a single receptor that is absolutely required by the parasite to invade.

"The discovery of a single receptor that can be targeted to stop the parasite infecting red blood cells offers the hope of a far more effective solution," Investigator at the Jenner Institute, Adrian Hill, said.

According to the Health Protection Agency, malaria is not endemic in the UK, but in the five years between 2006 and 2010, almost 1600 cases have occurred every year on average in travellers returning to or arriving in the UK from malaria-endemic countries.

Scottish Scientists step towards bringing life to inorganic matter

All life on Earth is carbon-based, which has led to the widespread assumption that any other life that may exist in the universe would also be carbon-based.

Excluding the possibility of elements other than carbon forming the basis of life is often referred to as carbon chauvinism.

Researchers at the University of Glasgow are looking to overcome this bias and provide new insights into evolution by attempting to create “life” from carbon-free, inorganic chemicals.

They’ve now taken the first tentative steps towards this goal with the creation of inorganic-chemical-cells, or iCHELLS.

Prof Cronin says the current theory of evolution is really a special theory of evolution because it only applies only to organic biology. He says that if he and his team are successful in creating life from inorganic matter, it could lead to a general theory of evolution.

"The grand aim is to construct complex chemical cells with life-like properties that could help us understand how life emerged and also to use this approach to define a new technology based upon evolution in the material world - a kind of inorganic living technology," said Prof Cronin.

"If successful this would give us some incredible insights into evolution and show that it's not just a biological process.

It would also mean that we would have proven that non carbon-based life could exist and totally redefine our ideas of design."



Prof Cronin gave a talk at TED Global earlier this year in Edinburgh where he said that if his team is successful in creating life while taking carbon out of the equation, it might reveal what other elements might be capable of producing life elsewhere in the universe and provide NASA with a better idea of what to look for in the search for extraterrestrial life.

The University of Glasgow team's paper "Modular Redox-Active Inorganic Chemical Cells: iCHELLs' is published in the journal Angewandte Chemie.

NPL Research: GeT-ting genes delivered

Confocal fluorescence micrograph of cells containing a gene delivered by GeT, encoding for the synthesis of green fluorescent protein.

NPL scientists have mimicked the ways viruses infect human cells and deliver their genetic material.

The research hopes to apply the approach to gene therapy – a therapeutic strategy to correct defective genes such as those that cause cancer.

Gene therapy is still in its infancy, with obvious challenges around targeting damaged cells and creating corrective genes. An equally important challenge is finding ways to transport the corrective genes into cells.

This is a problem, because of the poor permeability of cell membranes.

The research addresses this challenge by describing a model peptide sequence, dubbed GeT (gene transporter), which wraps around genes, transports them through cell membranes and helps their escape from intracellular degradation traps. The process mimics that which viruses use to infect human cells.

To prove the concept, the researchers used GeT to transfer a synthetic gene encoding for a green fluorescent protein that can be seen and monitored using fluorescence microscopy.

The design can serve as a potential template for non-viral gene delivery systems and future treatments of genetic disorders.

This research is part of the NPL-led international research project 'Multiscale measurements in biophysical systems', which is jointly funded by NPL and the Scottish Universities Physics Alliance.

Read the full article detailing this research published in Chemical Communications – the flagship journal of the Royal Society of Chemistry.

More on NPL’s work in Biotechnology

For more information please contact Max Ryadnov

Paper Thin Solar Cells - Folding a solar cell into an airplane

MIT's been making steady progress on creating solar cell-coated paper since 2010, and are excited to report the current findings of the project.

What looks and feels like an ordinary sheet of paper with a fine layer of coloured rectangles, is no ordinary piece of paper. Once connected to a couple of wires, it instantly generates electricity from solar power.

Additionally, the technology is almost as cheap and easy as printing a family snapshot from an inkjet printer. You can even fold it, slip it in your pocket, then unfold it again for later use.



The printing process uses vapours at relatively low temperatures (less than 120C/ 248F), to transfer five fine layers of photovoltaic cells onto a piece of untreated paper, plastic or even fabric.

The process takes place in a vacuum chamber where the layers are sprayed onto the same sheet of paper in successive passes, "creating a vapor-deposition process that can be carried out inexpensively on a vast commercial scale," according to MIT.

During an experiment to test the durability of the solar cells, a team of MIT students printed the cells onto a sheet of PET plastic (a thinner version than what is commonly used for soda bottles) and folded and unfolded it 1,000 times.

Remarkably, there was no impact of each fold on the performance of the solar cells. In contrast, a commercially produced solar cell on the same PET plastic failed after the first fold.

"We have demonstrated quite thoroughly the robustness of this technology," says MIT Professor of Electrical Engineering Vladimir Bulović.

Due to the low weight of the paper or plastic, "we think we can fabricate scalable solar cells that can reach record-high watts-per-kilogram performance," he added. "For solar cells with such properties, a number of technological applications open up."

Furthermore, by laminating the solar paper, the researchers were able to demonstrate that the system can be protected from rain and wind, and thus easily used outdoors.

This achievement in itself could offer an economical solution to current solar energy systems that use glass or other expensive materials as a base.

Scientists turn living cell into laser

For the first time, scientists have created a laser using a living cell.

To make this biological marvel, the researchers used a single human kidney cell, a bit of jellyfish protein, a couple mirrors and blue light.

A typical laser has a “gain medium” — a material that amplifies light given off by another source — and an “optical cavity” — mirrors set up in a way that lines up the light waves.

When the outside source of light is trained on the gain medium its atoms become excited and release photons.

As the photons ricochet between the mirrors, passing through the gain medium over and over again, they stimulate other atoms to release more photons. While the photons would normally exit in random directions the way light comes out of a flashlight, the mirrors direct the wavelengths into one beam, forming a laser.

The experiment

In this case, the researchers made their gain medium out of the jellyfish protein — green fluorescent protein (GFP) — which is what makes jellyfish bioluminescent and is widely used in cell biology to label cells.

They then engineered human embryonic kidney cells to produce GFP, and placed one such cell between two mirrors. They trained an outside source of blue light on the cell, which then emitted a laser beam visible with the naked eye.

Quoting researcher Seok-Hyun Yun, an optical physicist at Harvard Medical School and Massachusetts General Hospital in Boston, this Nature News article reports,

The width of the laser beam is “tiny” and “fairly weak” in its brightness compared to traditional lasers … but “an order of magnitude” brighter than natural jellyfish fluorescence, with a “beautiful green” colour.

Surprisingly, the laser didn’t harm the cell in the process — quite a feat considering that even the earliest lasers could drill holes in razor blades.

The future of living lasers

A living laser could have numerous scientific applications, say Yun and co-author Malte Gather, who published their study in Nature Photonics.

Cell biologists could use living lasers to study the structure of cells. As seen in the photo, the cell produces light in an irregular pattern which scientists could study to determine the internal structure of the cell.

Living lasers could be useful in biotechnology and medicine, to create drugs that are activated by light or to treat disease by attacking cells deep within the body. But the main challenge to developing such internal applications is providing the initial outside source of light.

In a press release, Gather says,

“One of our long-term goals will be finding ways to bring optical communications and computing, currently done with inanimate electronic devices, into the realm of biotechnology. That could be particularly useful in projects requiring the interfacing of electronics with biological organisms. We also hope to be able to implant a structure equivalent to the mirrored chamber right into a cell, which would the next milestone in this research.”

Photo: Microscope image of a single-cell living laser in action. (Nature Photonics and Malte Gather, Wellman Center for Photomedicine, Mass. General Hospital.)

No Relaxing for Cancer Cells

No relaxing for cancer cells

Many tumour cells would not be viable due to aberrant chromosome distribution if they had not developed a special trick. Scientists from the German Cancer Research Centre have investigated which genes are responsible for this survival strategy of cancer cells.

The revealed that cancer cells rely on the tension of specific protein fibers to be able to multiply. Thus, proteins which maintain this tension are promising targets for new, target-specific anticancer drugs: If they are switched off, cancer cells die.

The two centrosomes of a cell are responsible for cell division to proceed correctly. From these polar bodies in the cytoplasm protein fibers form which correctly distribute the duplicated chromosome set to the newly forming daughter cells. Seen under the microscope, these fibers have the shape of a spindle.

Cancer cells, however, often have more than two centrosomes. As a result, their spindle fibers do not necessarily assume the normal shape of a spindle with two poles; instead, they can have a dysfunctional, multipolar shape. Such malformed spindles distribute the chromosomes unevenly among the daughter cells, which are then no longer viable.

Hence, tumor cells only survive if they manage to partition their chromosomes correctly in spite of extra centrosomes. To do so, many cancer cells have developed a special trick: They form clusters of centrosomes.

Two clusters are formed per cell and a functioning bipolar spindle can develop between these two. Professor Dr. Alwin Krämer, head of a Clinical Cooperation Unit of DKFZ and Heidelberg University Hospitals has recognized this trick as a previously underrated Achilles’ heel of cancer cells, which might be used for destroying them.

Jointly with colleagues from DKFZ, Heidelberg University Hospitals, Mannheim Medical Faculty and Mayo Clinic in the U.S., he systematically investigated the question of which genes enable cancer cells to form centrosome clusters and, thus, to escape cell death.