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A new software package, RASPA, for simulating adsorption and diffusion of molecules in flexible nanoporous materials is presented. The code implements the latest state-of-the-art algorithms for molecular dynamics and Monte Carlo (MC) in various ensembles including symplectic/measure-preserving integrators, Ewald summation, configurational-bias MC, continuous fractional component MC, reactive MC and Baker's minimisation. We show example applications of RASPA in computing coexistence properties, adsorption isotherms for single and multiple components, self- and collective diffusivities, reaction systems and visualisation. The software is released under the GNU General Public License.  相似文献   
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This review discusses studies on marine macroalgae that have been investigated for their potential as sources of novel anti-cancer drugs. The review highlights the very large number of studies of crude, partially purified and purified seaweed extracts, collected from many locations, which have shown potential as sources of potent anti-cancer drugs when tested in vitro and/or in vivo. The activity of polysaccharides, polyphenols, proteinaceous molecules, carotenoids, alkaloids, terpenes and others is described here. In some reports, mechanistic studies have identified specific inhibitory activity on a number of key cellular processes including apoptosis pathways, telomerase and tumour angiogenesis. However, despite the potential shown by these studies, translation to clinically useful preparations is almost non-existent. It is hoped this review will serve as a source document and guide for those carrying out research into the potential use of macroalgae as a source of novel anti-cancer agents.  相似文献   
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The development ofM. gale oil as an insect repellent has created a requirement for cultivation of the plant. Botanical evidence indicates thatM. gale is likely to thrive on well—aerated acid peatland and could become a valuable crop on land of low agricultural value. Plant growth would be enhanced by the prevention of grazing and could be combined with softwood forestry since the trees would benefit from soil nitrogen enrichment thanks to the symbiotic association ofM. gale andFrankia. The economics of oil production would be improved if additional compounds of value such as pharmacologically active fiavonoids could be extracted from the by-products.  相似文献   
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The Biology of CRISPR-Cas: Backward and Forward   总被引:1,自引:0,他引:1  
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Deserts are particularly vulnerable to human impacts and have already suffered a substantial loss of biodiversity. In harsh and variable desert environments, large herbivores typically occur at low densities, and their large carnivore predators occur at even lower densities. The continued survival of large carnivores is key to healthy functioning desert ecosystems, and the ability to gather reliable information on these rare low density species, including presence, abundance and density, is critical to their monitoring and management. Here we test camera trap methodologies as a monitoring tool for an extremely rare wide-ranging large felid, the critically endangered Saharan cheetah (Acinonyx jubatus hecki). Two camera trapping surveys were carried out over 2–3 months across a 2,551km2 grid in the Ti-n-hağğen region in the Ahaggar Cultural Park, south central Algeria. A total of 32 records of Saharan cheetah were obtained. We show the behaviour and ecology of the Saharan cheetah is severely constrained by the harsh desert environment, leading them to be more nocturnal, be more wide-ranging, and occur at lower densities relative to cheetah in savannah environments. Density estimates ranged from 0.21–0.55/1,000km2, some of the lowest large carnivore densities ever recorded in Africa, and average home range size over 2–3 months was estimated at 1,583km2. We use our results to predict that, in order to detect presence of cheetah with p>0.95 a survey effort of at least 1,000 camera trap days is required. Our study identifies the Ahaggar Cultural Park as a key area for the conservation of the Saharan cheetah. The Saharan cheetah meets the requirements for a charismatic flagship species that can be used to “market” the Saharan landscape at a sufficiently large scale to help reverse the historical neglect of threatened Saharan ecosystems.  相似文献   
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Conceptually, premature initiation of post-wound angiogenesis could interfere with hemostasis, as it relies on fibrinolysis. The mechanisms facilitating orchestration of these events remain poorly understood, however, likely due to limitations in discerning the individual contribution of cells and extracellular matrix. Here, we designed an in vitro Hemostatic-Components-Model (HCM) to investigate the role of the fibrin matrix as protein factor-carrier, independent of its cell-scaffold function. After characterizing the proteomic profile of HCM-harvested matrix releasates, we demonstrate that the key pro-/anti-angiogenic factors, VEGF and PF4, are differentially bound by the matrix. Changing matrix fibrin mass consequently alters the balance of releasate factor concentrations, with differential effects on basic endothelial cell (EC) behaviors. While increasing mass, and releasate VEGF levels, promoted EC chemotactic migration, it progressively inhibited tube formation, a response that was dependent on PF4. These results indicate that the clot’s matrix component initially serves as biochemical anti-angiogenic barrier, suggesting that post-hemostatic angiogenesis follows fibrinolysis-mediated angiogenic disinhibition. Beyond their significance towards understanding the spatiotemporal regulation of wound healing, our findings could inform the study of other pathophysiological processes in which coagulation and angiogenesis are prominent features, such as cardiovascular and malignant disease.  相似文献   
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