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71.
<正>有关自动驾驶汽车运输货物的讨论与日俱增。但是,当控制自动驾驶车辆的电子系统出现故障并导致货物损失时应由谁来承担责任?在德国,法律法规和司法判例一致认为:运输公司在运输工业、商业和物流物资时对运输过程中属于运输公司保管下的物资损坏承担主要责任。例如,物流承运人应对货物固定不牢固而造成的损失负责。然而还有许多法律法规没法回答的问题,  相似文献   
72.
计算流体力学模拟可检测拉幅干燥机内的气体流动过程,并对喷嘴指板后端和通风机上端潜在的问题区域进行检测。蒸发过程的模拟表明,织物表面温度与水分的分布不均匀。然而,由于缺乏设备对实验模拟数据进行认征,故无法判断其可靠性。  相似文献   
73.
The physiological function of free fatty acids (FFAs) has long been regarded as indirect in terms of their activities as educts and products in metabolic pathways. The observation that FFAs can also act as signaling molecules at FFA receptors (FFARs), a family of G protein-coupled receptors (GPCRs), has changed the understanding of the interplay of metabolites and host responses. Free fatty acids of different chain lengths and saturation statuses activate FFARs as endogenous agonists via binding at the orthosteric receptor site. After FFAR deorphanization, researchers from the pharmaceutical industry as well as academia have identified several ligands targeting allosteric sites of FFARs with the aim of developing drugs to treat various diseases such as metabolic, (auto)inflammatory, infectious, endocrinological, cardiovascular, and renal disorders. GPCRs are the largest group of transmembrane proteins and constitute the most successful drug targets in medical history. To leverage the rich biology of this target class, the drug industry seeks alternative approaches to address GPCR signaling. Allosteric GPCR ligands are recognized as attractive modalities because of their auspicious pharmacological profiles compared to orthosteric ligands. While the majority of marketed GPCR drugs interact exclusively with the orthosteric binding site, allosteric mechanisms in GPCR biology stay medically underexploited, with only several allosteric ligands currently approved. This review summarizes the current knowledge on the biology of FFAR1 (GPR40), FFAR2 (GPR43), FFAR3 (GPR41), FFAR4 (GPR120), and GPR84, including structural aspects of FFAR1, and discusses the molecular pharmacology of FFAR allosteric ligands as well as the opportunities and challenges in research from the perspective of drug discovery.  相似文献   
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A simple schlieren technique is used to visualize strong gradients of refractive index in liquids under atmospheric conditions and elevated pressure. The gradients are mainly caused by concentration differences within a thin liquid sheet. A simple system using Matlab and open source applications is designed and applied to demonstrate the challenges and limitations of a quantitative approach for strong gradients in liquids. Possibilities for the optimization regarding the detection of strong gradients are shown, but rather qualitative than quantitative results are obtained.  相似文献   
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Mass spectral analysis of gaseous effluents from glow discharge polymerization of propylene confirms the formation of molecular propyne as an intermediate in the polymerization reaction. Observation of oligomeric species of mass number 138 or higher at the lowest monomer feed rate of the study indicates that a certain fraction of polymerization occurs in the gas phase.  相似文献   
78.
We present an iterative soft-output decoding algorithm for serially concatenated coding systems. It has better performance than the conventional noniterative decoding algorithm. When applied together with an outer convolutional code to the dicode channel with partial response (1 — D), we obtain an additional coding gain of about 1 dB at a bit-error rate of 10-4 after two iterations. This new algorithm can also be applied advantageously to satellite communication and fading channels.  相似文献   
79.
The nucleotide sequence of a fragment of 4867 base pairs of Saccharomyces cerevisiae chromosome II has been determined. The sequence contains three complete open reading frames. In addition to the already known gene RPB5, coding for a subunit shared by all three DNA directed RNA polymerases, two new open reading frames could be identified. YBR12.03 codes for a protein of 183 amino acids with homology to one of the proteins of the Bacillus subtilis riboflavin biosynthesis operon (RibG). Deletion mutants of YBR12.03 can germinate but stop growing after five to seven cell divisions on YPD. Supplementation with high concentrations of riboflavin does promote growth. YBR12.05 codes for a protein of 386 amino acids with homology to STI1, a stress-inducible protein of S. cerevisiae. Deletion mutants of YBR12.05 are not viable.  相似文献   
80.
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