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Todd McDevitt at the Georgia Institute of Technology and colleagues have found that adding biomaterials such as gelatin into clumps of stem cells (called "embryoid bodies") affected stem-cell differentiation without harming the cells. By incorporating magnetic particles into the biomaterials, they could control the locations of the embryoid bodies and how they assemble with one another. Compared to typical delivery methods, providing differentiation factors - retinoic acid, bone morphogenetic protein 4 (BMP4) and vascular endothelial growth factor (VEGF) - via microparticles induced changes in the gene and protein expression patterns of the aggregates. In the future, these new methods could be used to develop manufacturing procedures for producing large quantities of stem cells for diagnostic and therapeutic applications. The findings were presented on June 16 at the annual meeting of the International Society for Stem Cell Research. [full text]

In a paper published in Nature Photonics, University of Toronto researchers report the first efficient two-layer solar cell based on colloidal quantum dots (CQD) to capture both visible and near-infrared rays. CQDs are nanoscale materials that can be tuned to respond to specific wavelengths of the visible and invisible spectrum. By capturing such a broad range of light waves - wider than normal solar cells - tandem CQD solar cells can in principle reach up to 42 per cent efficiencies. The best single-junction solar cells are constrained to a maximum of 31 per cent efficiency. (In reality, solar cells that are on the roofs of houses and in consumer products have 14 to 18 per cent efficiency.) The researchers expect that in five years, solar cells using the graded recombination layer paper will be integrated into building materials and mobile devices.

ScienceDaily (Nov. 3, 2011) - Scientists have recently succeeded in rejuvenating cells from elderly donors (aged over 100). These old cells were reprogrammed in vitro to induced pluripotent stem cells (iPSC) and to rejuvenated and human embryonic stem cells (hESC): cells of all types can again be differentiated after this genuine "rejuvenation" therapy. The results represent significant progress for research into iPSC cells and a further step forwards for regenerative medicine.

Duke University engineer Nico Hotz has proposed a hybrid solar system in which sunlight heats a combination of water and methanol in a maze of tubes on a rooftop to produce hydrogen. The device is a series of copper tubes coated with a thin layer of aluminum and aluminum oxide and partly filled with catalytic nanoparticles. A combination of water and methanol flows through the tubes, which are sealed in a vacuum. Once the evaporated liquid achieves higher temperatures, tiny amounts of a catalyst are added, which produces hydrogen. This combination of high temperature and added catalysts produces hydrogen very efficiently, Hotz said. The resulting hydrogen can then be immediately directed to a fuel cell to provide electricity to a building during the day, or compressed and stored in a tank to provide power later. After two catalytic reactions, the system produced hydrogen much more efficiently than current technology without significant impurities, Hotz said. The resulting hydrogen can be stored and used on demand in fuel cells. "This set-up allows up to 95 percent of the sunlight to be absorbed with very little being lost as heat to the surroundings," he said. "This is crucial because it permits us to achieve temperatures of well over 200 degrees Celsius within the tubes. By comparison, a standard solar collector can only heat water between 60 and 70 degrees Celsius." Holtz performed a cost analysis, comparing a standard photovoltaic cell, a photocatalytic system, and the hybrid solar-methanol system.  He found that the hybrid system is the least expensive solution, with a total installation cost of $7,900 if designed to fulfill the requirements in summer. The paper describing the results of Hotz's analysis was named the top paper during the ASME Energy Sustainability Fuel Cell 2011 conference in Washington, D.C. Topics: Energy | Nanotech/Materials Science

Global fuel cell market is forecast to grow at a CAGR of over 18% by 2023, due to rising demand for fuel cell powered vehicles, including forklift, trains, etc. http://bit.ly/2ZUc0Yb

"MIT News examines research with the potential to reshape medicine and health care through new scientific knowledge, novel treatments and products, better management of medical data, and improvements in health-care delivery. "

"MIT News examines research with the potential to reshape medicine and health care through new scientific knowledge, novel treatments and products, better management of medical data, and improvements in health-care delivery. "

ScienceDaily (June 18, 2010) - Conventional solar cell efficiency could be increased from the current limit of 30 percent to more than 60 percent, suggests new research on semiconductor nanocrystals, or quantum dots, led by chemist Xiaoyang Zhu at The University of Texas at Austin.

The "ink" in the bioprinting process employed by Organovo is composed of spheres packed with tens of thousands of human cells. These spheres are assembled or "printed" on sheets of organic biopaper. By precisely placing the cells with the bioprinter, and providing them with the proper natural developmental cues, they do exactly what they do in nature: they self assemble into fully formed, functional tissue.

ScienceDaily (June 26, 2011) - In a paper published in Nature Photonics, U of T Engineering researchers report a new solar cell that may pave the way to inexpensive coatings that efficiently convert the sun's rays to electricity.

The work, which appears in a paper in the October 28 issue of the journal Nature, shows that "individuals can rapidly, consciously, and voluntarily control neurons deep inside their head," says Koch, the Lois and Victor Troendle Professor of Cognitive and Behavioral Biology and professor of computation and neural systems at Caltech.

Using stem cell technology, reproductive scientists in Texas, led by Dr. Richard R. Berhringer at the M.D. Anderson Cancer Center, have produced male and female mice from two fathers.

A team of UCSF researchers has engineered E. coli bacteria with the key molecular circuitry that will enable genetic engineers to program cells to communicate and perform computations.

A simple technique for stamping patterns invisible to the human eye onto a special class of nanomaterials has been developed by researchers at Vanderbilt University. The new method works with porous nanomaterials that are riddled with tiny voids, which give them unique optical, electrical, chemical, and mechanical properties. There are nanoporous forms of gold, silicon, alumina, and titanium oxide, among others. The technique involves the creation of pre-mastered stamps using traditional, but complex, clean room processes and then using the stamps to create patterns using a new process called direct imprinting of porous substrates (DIPS). DIPS can create a device in less than a minute, regardless of its complexity. The smallest pattern the researchers have made to date has features of only a few tens of nanometers (about the size of a single fatty acid molecule). They have also succeeded in imprinting the smallest pattern yet reported in nanoporous gold, one with 70-nanometer features. The first device the group has created is a "diffraction-based" biosensor that can be configured to identify a variety of different organic molecules, including DNA, proteins and viruses. The researchers envision a wide range of applications including drug delivery, chemical and biological sensors, solar cells, and battery electrodes.

"For the first time, researchers power an implantable electronic device using an electrical potential - a natural battery - deep in the inner ear."

"All of D-Lab's classes assess the needs of people in less-privileged communities around the world, examining innovations in technology, education or communications that might address those needs. The classes then seek ways to spread word of these solutions - and in some cases, to spur the creation of organizations to help disseminate them. Specific projects have focused on improved wheelchairs and prosthetics; water and sanitation systems; and recycling waste to produce useful products, including charcoal fuel made from agricultural waste."