988 resultados para Metastasio, Pietro, 1698-1782.
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本发明涉及一种姚虻唾液腺免疫调节肽及其基因和应用,属于生物医学领域。该免疫调节肽是中国虻科昆虫唾液腺免疫调节肽基因编码的一种线状多肽,其全序列为:甘氨酸-甘氨酸-缬氨酸-丝氨酸-甘氨酸-缬氨酸-丝氨酸-天冬氨酸-苯丙氨酸-谷氨酸-脯氨酸-异亮氨酸-谷氨酸-缬氨酸-丝氨酸- 甘氨酸-谷氨酸-天冬氨酸-酪氨酸-天冬酰胺-丝氨酸-天冬氨酸-谷氨酸 -丙氨酸-天冬氨酸-谷氨酸-天冬氨酸-甘氨酸-赖氨酸-丙氨酸。免疫调节肽基因由362个核苷酸组成,其中编码成熟编码姚虻唾液腺免疫调节肽为第 115-204位核苷酸。该姚虻唾液腺免疫调节肽作为抑制多种细胞因子的应用。本发明的免疫调节肽具有结构简单、人工合成方便、抗菌活性强等特点。
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本发明属于生物医学领域。大蹼铃蟾抗菌肽,为从中国两栖类动物大蹼铃蟾皮肤分泌物中分离得到的一种单链多肽,分子量2697.6,等电点10.2,多肽一级全序列结构为:NH2—GIGGVLLSAGKAALKGLAKVLAAKYANN-NH2。制备方法是将活体大蹼铃蟾用水清洗干净,置于带盖的玻璃容器中,滴加无水乙醚,密闭容器3—5分钟,可见大量的泡沫状物质从大蹼铃蟾皮肤分泌出来,收集分泌物,离心去除沉淀、冷冻干燥后,经离子交换、凝胶过滤、高压液相反相柱层析分离纯化后即得到。大蹼铃蟾抗菌肽具有广谱和显著的抑制细菌和真菌生长作用,作为广谱抗微生物物质在制备治微生物感染疾病药物的应用。
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An outline is given of aquaculture and fisheries in Asia, providing information of use to students whose work can influence laws, rules, policy and regulations on aquaculture and fisheries, with the view in mind to sustainable aquaculture. In this issue, the following countries are examined: China, Indonesia, and Bangladesh.
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We bring together two areas of terahertz (THz) technology that have benefited from recent advancements in research, i.e., graphene, a material that has plasmonic resonances in the THz frequency, and quantum cascade lasers (QCLs), a compact electrically driven unipolar source of THz radiation. We demonstrate the use of single-layer large-area graphene to indirectly modulate a THz QCL operating at 2.0 THz. By tuning the Fermi level of the graphene via a capacitively coupled backgate voltage, the optical conductivity and, hence, the THz transmission can be varied. We show that, by changing the pulsing frequency of the backgate, the THz transmission can be altered. We also show that, by varying the pulsing frequency of the backgate from tens of Hz to a few kHz, the amplitude-modulated THz signal can be switched by 15% from a low state to a high state. © 2009-2012 IEEE.
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国家“十五”重大科技专项(2202AA601021); 国家杰出青年科学基金项目(39925007); 中国科学院知识创新工程重要方向项目(KSCX2SW102); 中国科学院水生生物研究所学科前沿课题(2002); 淡水生态与生物技术国家重点实验室课题(2002FB11)项目资助
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This paper studies the excitability properties of a generalized FitzHugh-Nagumo model. The model differs from the classical FitzHugh-Nagumo model in that it accounts for the effect of cooperative gating variables such as activation of calcium currents. Excitability is explored by unfolding a pitchfork bifurcation that is shown to organize five different types of excitability. In addition to the three classical types of neuronal excitability, two novel types are described and distinctly associated to the presence of cooperative variables. © 2012 Society for Industrial and Applied Mathematics.
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An online scheduling of the parameter ensuring in addition to closed loop stability was presented. Attention was given to saturated linear low-gain control laws. Null controllability of the considered linear systems was assumed. The family of low gain control laws achieved semiglobal stabilization.
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This paper is concerned with the development of efficient algorithms for propagating parametric uncertainty within the context of the hybrid Finite Element/Statistical Energy Analysis (FE/SEA) approach to the analysis of complex vibro-acoustic systems. This approach models the system as a combination of SEA subsystems and FE components; it is assumed that the FE components have fully deterministic properties, while the SEA subsystems have a high degree of randomness. The method has been recently generalised by allowing the FE components to possess parametric uncertainty, leading to two ensembles of uncertainty: a non-parametric one (SEA subsystems) and a parametric one (FE components). The SEA subsystems ensemble is dealt with analytically, while the effect of the additional FE components ensemble can be dealt with by Monte Carlo Simulations. However, this approach can be computationally intensive when applied to complex engineering systems having many uncertain parameters. Two different strategies are proposed: (i) the combination of the hybrid FE/SEA method with the First Order Reliability Method which allows the probability of the non-parametric ensemble average of a response variable exceeding a barrier to be calculated and (ii) the combination of the hybrid FE/SEA method with Laplace's method which allows the evaluation of the probability of a response variable exceeding a limit value. The proposed approaches are illustrated using two built-up plate systems with uncertain properties and the results are validated against direct integration, Monte Carlo simulations of the FE and of the hybrid FE/SEA models. © 2013 Elsevier Ltd.
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A new highly pathogenic muscle-infecting species of the genus Myxobolus Butschli, 1882 is described from the Prussian carp, Carassius gibelio (Bloch, 1782) using spore morphology and SSU rDNA sequence data. Phylogenetic analyses elucidated relationship of the newly described Myxobolus lentisuturalis to other Myxobolus species and supported its position of an independent species.
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Depth profiles of carrier concentrations in GaMnSb/GaSb are investigated by electrochemistry capacitance-voltage profiler and electrolyte of Tiron. The carrier concentration in GaMnSb/GaSb measured by this method is coincident with the results of Hall and X-ray diffraction measurements. It is indicated that most of the Mn atoms in GaMnSb take the site of Ga, play a role of acceptors, and provide shallow acceptor level(s).
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面向桌面虚拟环境,在分析通用交互设备特点的基础上,提出了具有广泛适用性的双手交互的设备组合;根据虚拟现实通用交互任务的需求,结合设备特点,提出了为左、右手设备分配不同的子任务的策略;组合不同的单手交互技术,提出了包括基于辅助平面的双手交互等3个适用于典型桌面设备组合的双手交互技术;开发了双手交互技术工具箱,并进行了应用验证·
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以汕头市六区一县为研究区域,采用1996—2007年土地利用详查变更数据,分析
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海底沉积物声学测量数据中包含着的频谱特征和信息,是区分和判别沉积物类型的重要依据。应用频谱分析方
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通过使用激光散射扫描的方法,定性地研究非掺杂半绝缘LEC砷化镓(100)方向生产的晶体中砷沉淀在晶体径向截面分布,得到了在一种特定热场中生长的晶体中存在4个砷沉淀的聚集中心结论,而这4个聚集中心却正好是晶体上位错密度相对较低的区域.作者主要研究了这种分布和位错之间的关系,分析其形成过程,并得出在晶体生长及后期退火过程中,位错在晶体中起到了输送砷原子的管道作用,加速了砷原子在晶体中的扩散过程,导致网格位错密集区的大直径砷沉淀的密度相对位错稀疏区和位错线区的砷沉淀密度较低.