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1.
Nutrient Cycling in Agroecosystems - Reducing agriculturally derived diffuse contaminant losses (via non-point sources) from land to water has proven difficult for decades. Owing to the diversity...  相似文献   
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Liquid-phase adsorption has hardly been established in micro-flow, although this constitutes an industrially vital method for product separation. A micro-flow UV-photo isomerization process converts cis-cyclooctene partly into trans-cyclooctene, leaving an isomeric mixture. Trans-cyclooctene adsorption and thus separation was achieved in a fixed-bed micro-flow reactor, packed with AgNO3/SiO2 powder, while the cis-isomer stays in the flow. The closed-loop recycling-flow has been presented as systemic approach to enrich the trans-cyclooctene from its cis-isomer. In-flow adsorption in recycling-mode has hardly been reported so that a full theoretical study has been conducted. This insight is used to evaluate three process design options to reach an optimum yield of trans-cyclooctene. These differ firstly in the variation of the individual residence times in the reactor and separator, the additional process option of refreshing the adsorption column under use, and the periodicity of the recycle flow.  相似文献   
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Laminopathies are a clinically heterogeneous group of disorders caused by mutations in the LMNA gene, which encodes the nuclear envelope proteins lamins A and C. The most frequent diseases associated with LMNA mutations are characterized by skeletal and cardiac involvement, and include autosomal dominant Emery–Dreifuss muscular dystrophy (EDMD), limb-girdle muscular dystrophy type 1B, and LMNA-related congenital muscular dystrophy (LMNA-CMD). Although the exact pathophysiological mechanisms responsible for LMNA-CMD are not yet understood, severe contracture and muscle atrophy suggest that mutations may impair skeletal muscle growth. Using human muscle stem cells (MuSCs) carrying LMNA-CMD mutations, we observe impaired myogenic fusion with disorganized cadherin/β catenin adhesion complexes. We show that skeletal muscle from Lmna-CMD mice is unable to hypertrophy in response to functional overload, due to defective fusion of activated MuSCs, defective protein synthesis and defective remodeling of the neuromuscular junction. Moreover, stretched myotubes and overloaded muscle fibers with LMNA-CMD mutations display aberrant mechanical regulation of the yes-associated protein (YAP). We also observe defects in MuSC activation and YAP signaling in muscle biopsies from LMNA-CMD patients. These phenotypes are not recapitulated in closely related but less severe EDMD models. In conclusion, combining studies in vitro, in vivo, and patient samples, we find that LMNA-CMD mutations interfere with mechanosignaling pathways in skeletal muscle, implicating A-type lamins in the regulation of skeletal muscle growth.  相似文献   
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Mine Water and the Environment - Acid mine drainage (AMD) is a major environmental challenge for the mining industry in northern climates. Laboratory-scale experiments were conducted to test...  相似文献   
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This study investigated the digestibility of proteins in a pea protein-fortified sponge cake, as well as the impact of the degree of structure of the bolus produced by elderly subjects on the digestibility of proteins by combining ex vivo and in vitro approaches via the standardized protocol INFOGEST. The sponge cakes were consumed by a group of 20 elderly subjects with contrasting physiology, their boli were recovered just before swallowing, and their apparent viscosity was measured to delineate the bolus degree of structure. According to this criterion, two pools were formed with boli from subjects selected at the extremes: low viscosity and high viscosity, with apparent viscosity values (at 120 s−1) of 124 ± 18 and 208 ± 19 Pa s, respectively. The sponge cakes and the two pools underwent in vitro digestion. Protein hydrolysis kinetics was followed by measuring the released primary amino groups (NH2) and by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis at different time points. For all samples, the representative bands of pea proteins disappear gradually during digestion, accompanied by the appearance of bands indicating the presence of proteins with MW < 15 kDa. In addition, the NH2 concentrations increase over time and do not differ between sponge cake and pea protein isolate. Moreover, the degree of structure of the food bolus has no significant effect on the concentration of NH2 released. These results showed that pea proteins in a fortified sponge cake are bioaccessible under standardized conditions and that the degree of structure of the bolus did not influence protein digestibility for these foods.  相似文献   
6.
Anisotropic sintering, including shrinkage and grain growth, was examined for c-axis-oriented (Sr,Ca)2NaNb5O15 (SCNN) ceramics, which were prepared by colloidal processing under a magnetic field. In the c-axis-oriented SCNN powder compact, shrinkage and grain growth along the c-axis were higher than those along the a-axis. The anisotropic microstructural development was clearly associated with anisotropic sintering shrinkage. X-ray diffraction, scanning electron microscopy, and energy back scattering diffraction showed that the grain growth of oriented particles by including random grains contribute to the development of the oriented microstructure. Finally, the highly crystal-oriented SCNN ceramics with a densified microstructure were obtained through anisotropic sintering. These results clearly showed the potential to develop a well-defined anisotropic microstructure during sintering by designing and controlling the particle packing structure in a powder compact.  相似文献   
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The COVID-19 pandemic has affected the educational systems worldwide, leading to the near-total closures of schools, universities, and colleges. Universities need to adapt to changes to face this crisis without negatively affecting students’ performance. Accordingly, the purpose of this study is to identify and help solve to critical challenges and factors that influence the e-learning system for Computer Maintenance courses during the COVID-19 pandemic. The paper examines the effect of a hybrid modeling approach that uses Cloud Computing Services (CCS) and Virtual Reality (VR) in a Virtual Cloud Learning Environment (VCLE) system. The VCLE system provides students with various utilities and educational services such as presentation slides/text, data sharing, assignments, quizzes/tests, and chatrooms. In addition, learning through VR enables the students to simulate physical presence, and they respond well to VR environments that are closer to reality as they feel that they are an integral part of the environment. Also, the research presents a rubric assessment that the students can use to reflect on the skills they used during the course. The research findings offer useful suggestions for enabling students to become acquainted with the proposed system’s usage, especially during the COVID-19 pandemic, and for improving student achievement more than the traditional methods of learning.  相似文献   
10.
Nutritional research is currently entering the field of personalized nutrition, to a large extent driven by major technological breakthroughs in analytical sciences and biocomputing. An efficient launching of the personalized approach depends on the ability of researchers to comprehensively monitor and characterize interindividual variability in the activity of the human gastrointestinal tract. This information is currently not available in such a form. This review therefore aims at identifying and discussing published data, providing evidence on interindividual variability in the processing of the major nutrients, i.e., protein, fat, carbohydrates, vitamins, and minerals, along the gastrointestinal tract, including oral processing, intestinal digestion, and absorption. Although interindividual variability is not a primary endpoint of most studies identified, a significant number of publications provides a wealth of information on this topic for each category of nutrients. This knowledge remains fragmented, however, and understanding the clinical relevance of most of the interindividual responses to food ingestion described in this review remains unclear. In that regard, this review has identified a gap and sets the base for future research addressing the issue of the interindividual variability in the response of the human organism to the ingestion of foods.  相似文献   
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