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1.
Profilins were discovered in the 1970s and were extensively studied for their significant physiological roles. Profilin1 is the most prominent isoform and has drawn special attention due to its role in the cytoskeleton, cell signaling, and its link to conditions such as cancer and vascular hypertrophy. Recently, multiple mutations in the profilin1 gene were linked to amyotrophic lateral sclerosis (ALS). In this review, we will discuss the physiological and pathological roles of profilin1. We will further highlight the cytoskeletal function and dysfunction caused by profilin1 dysregulation. Finally, we will discuss the implications of mutant profilin1 in various diseases with an emphasis on its contribution to the pathogenesis of ALS.  相似文献   
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In this study, the author provides a brief and concise summary of empirical investigations pertaining to forecasting with special reference to the accuracy of different forecasting techniques. The study mainly focuses on comparisons of the accuracy of these techniques. The comparisons cover both quantitative and qualitative methods. In addition the summary includes studies seeking to test or improve accuracy by combining forecasting techniques.  相似文献   
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Systemic Practice and Action Research - A well-designed organizational structure is a cornerstone of achieving an organization’s goals while suiting the environmental challenges. Structural...  相似文献   
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This study explores the flotation behavior of chalcopyrite in the presence of different concentrations of sodium sulfide (Na2S·9H2O) at pH 12 under controlled potential conditions. It was observed that the flotation of chalcopyrite is not depressed completely when the pulp potential is low, even at high concentrations of sodium sulfide, i.e., 10?1–10?2 mol/L. However, a partial and controlled oxidation of pulp does enhance the effectiveness of sodium sulfide on the depression of chalcopyrite. Characterization of the chalcopyrite particle surface by X-ray photoelectron spectroscopy allowed the identification of hydrophilic and hydrophobic surface species, which are responsible for the depression and flotation of chalcopyrite. Changes in pulp potential were found to be an effective float controlling parameter, by which Na2S can be used to initiate or depress the flotation behavior of chalcopyrite.  相似文献   
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Heterogeneous community entails a number of social groups that adopt similar/different social norms. In such community, new individuals who join a new social group should be able to decide with which group they could assimilate based on their capabilities/values/manners. Otherwise, they would be penalized by other members in the group for violating some norms which they cannot comply.Using this approach, software agents would have better reasoning in simulating human society. In this paper, the authors propose a norms assimilation theory, in which a new agent attempts to assimilate with a social group's norms. This theory builds an approach to norm assimilation, analyzes the cases for an agent to decide to assimilate with a social group and develops a mathematical model to measure the assimilation cost and the agent's ability. The approach is developed based on the agent's internal belief about its ability and desire, and its external belief about the cost of assimilating with a number of social groups. The significance of this research is two-fold. Firstly, the study paves the way to future design of intelligent systems, i.e., software agents or robots, to closely mimic human social interactions.Secondly, the norm assimilation using agent-based system could be potentially utilized to simulate some social issues such as immigrants, new students, expatriate etc. The experiments that have been conducted demonstrate that an agent in the domain is able to calculate the assimilation cost and decide which social group to join.  相似文献   
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This study presents three genera and 10 species of flies (order: Diptera) as new country records from the Kingdom of Saudi Arabia (KSA). The flies were identified from Rawdhat Khorim National Park in Riyadh Region, the central region of KSA. The newly recorded genera are Glabellula (Mythicomyiidae), Phora (Phoridae) and Ceroptera (Sphaeroceridae), and the newly recorded species are Dilophus lingens (Bibionidae), Stichopogon deserti (Asilidae), Glabellula sp. (Mythicomyiidae), Phora sp. (Phoridae), Liriomyza lutea (Agromyzidae), Ceroptera aharonii (Sphaeroceridae), Trixoscelis deemingi, Trixoscelis migueli and Trixoscelis puncticornis (Trixoscelididae), and Physiphora leucotricha (Ulidiidae). Glabellula sp. and Phora sp. have been identified only to the genus level and are listed herein only because this is the first time they have been recorded in KSA, and additional specimens are required for their accurate identification to the species level. Also, this is the first record of Trixoscelis deemingi Wo?nica and Trixoscelis migueli Wo?nica from the Palaearctic Region. Distribution, diagnoses, remarks on biology and coloured photos are given for the recorded taxa. A list of associated fly species that were previously recorded in KSA and are identified from the study area in the present study is also presented. Zoogeographically, 33% of the identified fly species showed both Afrotropical and Palaearctic affinities, while 17% were of only Palaearctic affinity, and 8% were of only Afrotropical affinity. Elements from other regions were apparently nil. The results support the idea that the central Arabian Desert, which includes the present study area, is a transitional zone between the Palaearctic and Afrotropical regions.  相似文献   
9.
A Functional Equation Governing the Motion of a Compressible Fluid Flow   总被引:1,自引:0,他引:1  
Introduction  In1952EberhardHopf[1]deducedadynamicalequationgoverningtheevolutionofthecharacteristicfunctionalofaturbulentvelocityfieldinanincompressiblefield,asaconsequenceoftheNavier-Stokesandcontinuityequations.Thepurposeofthispaperistostudythecasewhenthefluidiscompressible.Theword“fluid”denotesanyliquidorgaseousmedium,themostimportantdifferencebetweenthemechanicalpropertiesofliquidsandgasesliesintheirbulkelasticity,thatis,intheircompressibility.Gasescanbecompressedmuchmorethanliquids…  相似文献   
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The potential use of Samaar Morr (JUNCUS A CUTUS) plant as fibrous material in papermaking was evaluated in this study. The chemical analysis and fibre charactersitcs of this plant were determined for better understanding its behaviour in papermaking. Samaar morr stalks were subjected to sulfur-free three-stage (peroxyformic acid, formic acid, peroxyformic acid) Milox process. Some conventional pulping experiments such as soda,soda-anthraquinon (S-AQ), kraft and kraft-AQ pulping in addition to two- and one-stage peroxyformic acid pulping were also carried out for comparison with the three-stage peroxyformic acid pulping method. It was found that the pulping with Milox process produces pulp with good properties compared to the pulp produced from the other methods. The physical and optical properties of different pulps were also examined. The behaviour of Milox samaar morr pulp towards bleaching with alkaline hydrogen peroxide has been investigated in presence and absence of formic acid. The results showed that the final brightness about 81.5% ISO could be achieved after 3% peroxide in two bleaching steps with formic acid treatment between the two steps.  相似文献   
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