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New Synthetic Leaf Uses the Power of the Sun to Generate Hydrogen
An artificial leaf developed at the Ulsan National Institute of Science and Technology (UNIST) simulates the process of underwater photosynthesis of aquatic plants to split water into hydrogen and oxygen, which can be harvested for fuel. No carbon dioxide emissions are generated, and the technology can be used as an inexpensive and stable hydrogen fuel for hydrogen-fuel-cell vehicles.
“We aim to achieve 10% enhanced light harvesting efficiency within three years,” said Professor Jae Sung Lee.
Climate Change May Have a More Negative Effect on Biological Diversity of Animals Than Previously Thought
Researchers from Senckenberg Research Institute and Natural History Museum, Biodiversity and Climate Research Centre, investigated the vulnerability of more than 700 European plant and animal species to future climate change. For the first time, they combined these models with data on interactions of plants with their animal pollinators and seed dispersers. Te simulation indicated that the trigger for extinction that occurs as a result of climate change originates mainly from plant species and is indirectly transferred to animal species.
Tis domino effect threatens animal species that only interact with a small number of plant species, since they are more sensitive to climate change than generalists. “In the future, these specialists will therefore face a double threat. According to our analyses, they are restricted to a narrow climatic niche and are therefore also directly threatened by rising temperatures in the future,” explained Dr. Christian Hof.
Te study revealed that climate change not only poses a direct threat to many animal species, but that additional indirect effects also play a role, say the researchers.
Small-Molecule Drug Halts Melanoma Spread by up to 90%
A small-molecule drug compound stops genes from producing RNA molecules and certain proteins in melanoma tumors. This gene activity, or transcription process, causes the disease to spread—but the compound can shut it down.
Richard Neubig, a pharmacology professor at Michigan State University, said, “It’s been a challenge developing small-molecule drugs that can block this gene activity that works as a signaling mechanism known to be important in melanoma progression. Our chemical compound is actually the same one that we’ve been working on to potentially treat the disease scleroderma, which now we’ve found works effectively on this type of cancer.”
The researchers discovered that the compound was able to stop proteins, known as myocardin- related transcription factors, from initiating the gene transcription process in melanoma cells. These triggering proteins are initially turned on by another protein called RhoC, which is found in a signaling pathway that can cause the disease to aggressively spread in the body.
Te compound reduced the migration of melanoma cells by 85–90%. It significantly reduced tumors, specifically in the lungs of mice that had been injected with human melanoma cells.
Study Examines Antibiotic-Resistant Bacterial Persister Cells
New findings on bacteria that survive antibiotic treatment could lead to the discovery of novel antibiotics that target these challenging persister bacteria. Alexander Harms of the Faculty of Science, University of Copenhagen, explained the mechanism by which these bacteria resist antibiotics. “Tis amazing resilience is oſten due to hibernation in a physiological state called persistence where the bacteria are tolerant to multiple antibiotics and other stressors. Bacterial
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cells can switch into persistence by activating dedicated physiological programs that literally pull the plug of important cellular processes. Once they are persisters, the bacteria may sit through even long-lasting antibiotic therapy and can resuscitate to cause relapsing infections at any time aſter the treatment is abandoned.”
Recent work has revealed the molecular architecture of several cellular pathways that form the basis of bacterial persisters; these results confirmed that persistence is linked to slow growth or dormancy. Bacterial persistence can thus be compared to the hibernation of animals. Across many different bacteria, these programs are controlled by a regulatory compound known as the “magic spot,” which is instrumental in the persistence phenomenon.
5HÁHFWLRQ 6FDWWHU )UHH Transparent Conductor Could Lead to More (IÀFLHQW 2SWRHOHFWURQLFV
Most current technology in electronic and optoelectronic devices is based on indium tin oxide (ITO) as a transparent conductor. This semiconductor, however, is costly to produce and is not mechanically flexible. In their search for a transparent conductor material to replace ITO, researchers at ICFO, The Institute of Photonic Sciences, engineered a room- temperature processed multilayer transparent conductor optimizing the antireflection properties to obtain high optical transmissions and low losses, with mechanical flexibility.
The researchers applied an Al-doped ZnO overcoat and a TiO2
undercoat layer to a highly
conductive Ag ultrathin film. Using destructive interference, they showed that the proposed multilayer structure could lead to an optical loss of approximately 1.6% and optical transmission greater than 98% in the visible range. According to the team, “We have used a simple design to achieve a transparent conductor with the highest performance to date and at the same time other outstanding attributes required for relevant applications in industry.” Their development resulted in a record fourfold improvement over ITO.
JANUARY/FEBRUARY 2017
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