851 research outputs found

    Project Omoverhi : a thermal storage solution

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    One principal energy source that is underutilized in the world today is solar energy. While the United States has tried to make a push for reusable and \u27green\u27 energy sources, these sources are frequently overlooked in developing nations. While the set up costs of solar energy may be expensive due to installation and the high cost of certain parts, the savings over time is well worth the initial cost. In many developing nations large areas of the country are off of the power grid or have inconsistent power. One way to help people living in these areas is by introducing the use of solar power. Unfortunately one major drawback to using solar energy is the difficulty of storing it. While photovoltaic panels can store energy in batteries, they are extremely expensive and inefficient. Using solar collectors that are either manufactured or handmade rather than PV panels can be more than four times as efficient and cost much less. The one negative issue with solar collectors is that they will only work when the sun is out. The 2011 to 2012 Project Omoverhi team\u27s goal was to utilize this energy from solar collectors and store it in a thermal storage container. The stored energy could then be used when direct sunlight was not available. Using paraffin wax as a phase change material because of its melting temperature and excellent storage properties, Project Omoverhi was able to achieve this goal and create an affordable, easy to use system that can be attached to a solar collector. The system was tested to determine if it would enable an incubator to keep a steady temperature that would meet the requirements of a premature infant or successfully hatch chicken eggs. Data collected showed that Project Omoverhi\u27s design is an effective way to store heat and energy from a solar collector so that it can be utilized as needed

    A triple helix stabilizes the 3' ends of long noncoding RNAs that lack poly(A) tails

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    The MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) locus is misregulated in many human cancers and produces an abundant long nuclear-retained noncoding RNA. Despite being transcribed by RNA polymerase II, the 3' end of MALAT1 is produced not by canonical cleavage/polyadenylation but instead by recognition and cleavage of a tRNA-like structure by RNase P. Mature MALAT1 thus lacks a poly(A) tail yet is expressed at a level higher than many protein-coding genes in vivo. Here we show that the 3' ends of MALAT1 and the MEN beta long noncoding RNAs are protected from 3'-5' exonucleases by highly conserved triple helical structures. Surprisingly, when these structures are placed downstream from an ORF, the transcript is efficiently translated in vivo despite the lack of a poly(A) tail. The triple helix therefore also functions as a translational enhancer, and mutations in this region separate this translation activity from simple effects on RNA stability or transport. We further found that a transcript ending in a triple helix is efficiently repressed by microRNAs in vivo, arguing against a major role for the poly(A) tail in microRNA-mediated silencing. These results provide new insights into how transcripts that lack poly(A) tails are stabilized and regulated and suggest that RNA triple-helical structures likely have key regulatory functions in vivo

    Nanostructure of cellulose microfibrils in spruce wood

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    The structure of cellulose microfibrils in wood is not known in detail, despite the abundance of cellulose in woody biomass and its importance for biology, energy, and engineering. The structure of the microfibrils of spruce wood cellulose was investigated using a range of spectroscopic methods coupled to small-angle neutron and wide-angle X-ray scattering. The scattering data were consistent with 24-chain microfibrils and favored a “rectangular” model with both hydrophobic and hydrophilic surfaces exposed. Disorder in chain packing and hydrogen bonding was shown to increase outwards from the microfibril center. The extent of disorder blurred the distinction between the I alpha and I beta allomorphs. Chains at the surface were distinct in conformation, with high levels of conformational disorder at C-6, less intramolecular hydrogen bonding and more outward-directed hydrogen bonding. Axial disorder could be explained in terms of twisting of the microfibrils, with implications for their biosynthesis

    Review of Methodologies for Land Degradation Neutrality Baselines: Sub-National case studies from Costa Rica and Namibia

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    The objective of this report is to identify entry points and challenges for subnational LDN baselines in order to inform subnational planning processes as potential vehicle for the implementation of LDN targets on the ground. For this purpose two focus regions were chosen within two of the countries – namely Namibia and Costa Rica – that participated in the first LDN pilot phase. The focus areas in Namibia and Costa Rica are the regions of Otjozondjupa and Rio Jesus Maria watershed respectively. Both Namibia and Costa Rica provide interesting case studies given the differences in types of land degradation, national capacities, and land resources
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