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121.
This paper describes the procedures established by the present regulation for high-tension network expansions, studies its optimality and points its main problems. According to the present regulatory scheme, the decision to expand the high-tension network system is on the hands of the private sector. A simple model of the Argentine electricity system and its regulation allowed the simulation of cases in which the present ‘Public Contest’ method could result in the rejection of socially desirable projects and the acceptance of undesirable ones. Three main reasons for the existence of wrong incentives to investment are found. First, since consumers are not included in the mechanism, they have no way to reveal their willingness-to-pay for the investment. Second, the approximation of the future use of the line is done in such a way that it leaves important nodes under represented, thereby affecting the optimality of the mechanism. Third, the profit agents obtain from a line may not be related to their use, e.g. the generators profits depend also on generation costs.  相似文献   
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This paper presents the algorithms and system architecture of an autonomous racecar. The introduced vehicle is powered by a software stack designed for robustness, reliability, and extensibility. To autonomously race around a previously unknown track, the proposed solution combines state of the art techniques from different fields of robotics. Specifically, perception, estimation, and control are incorporated into one high‐performance autonomous racecar. This complex robotic system, developed by AMZ Driverless and ETH Zürich, finished first overall at each competition we attended: Formula Student Germany 2017, Formula Student Italy 2018 and Formula Student Germany 2018. We discuss the findings and learnings from these competitions and present an experimental evaluation of each module of our solution.  相似文献   
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Fluorescence quenching techniques are used to investigate the accessibility of a model biorecognition element-reporter group system when in buffer, surface-adsorbed, and covalently attached to a silica surface. The site-selective fluorescent reporter group, 6-acryloyl(dimethylamino)naphthalene (acrylodan, Ac), is attached covalently (at cysteine-34) to bovine and human serum albumin (BSA and HSA, respectively) and serves as a surrogate recognition element-reporter group system. Molecular oxygen is used to quench the Ac fluorescence and the accessibility, in the form of bimolecular rate constants (kq), in each model system is quantified. Although one might expect these systems to exhibit similar behavior, differences in quenching characteristics are observed, such as wavelength dependency of the Stern-Volmer quenching constant (KSV) for the native proteins in buffer. BSA-Ac exhibits wavelength dependent KSV values as well as a blue-shifted emission spectrum on O2 addition. Physisorption of BSA-Ac onto a fused-silica optical fiber lowers the accessibility of Ac to O2, whereas covalent attachment of BSA-Ac to APTES/glutaraldehyde-modified silica enhances the accessibility of the Ac reporter group to O2.  相似文献   
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The pathogenetic effector functions of hepatitis B virus (HBV)-specific CD4+, Th1 cells were analyzed in two inbred lineages of HBV transgenic mice, one of which overexpresses the HBV large envelope protein rendering the hepatocytes hypersensitive to the cytopathic effects of IFN-gamma, and another that expresses all of the HBV proteins and replicates the virus in the liver. Transfer of HBV envelope-specific Th1 cells resulted in recognition of viral Ag expressed by hepatic nonparenchymal cells, cytokine release, and a transient necroinflammatory liver disease in both lineages. The liver disease was very severe in the IFN-gamma-sensitive lineage, and it was less severe in the lineage that replicates the HBV genome; nonetheless, in this lineage the Th1 cytokines produced by these cells suppressed viral replication in the liver. These results demonstrate that CD4+ T cells with a Th1 functional phenotype can perform pathogenetic and antiviral effector functions in vivo. This suggests that CD4+ T cells can contribute directly to disease pathogenesis and inhibit viral replication during HBV infection.  相似文献   
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A case of intestinal infarction due to superior mesenteric artery embolism is described in a 30-year-old female with Crohn's disease. This was accompanied by bladder opacification following enteral iopamidol administered at endoscopic retrograde cholangiopancreatography. The likely mechanism of this finding is transmural and transperitoneal absorption of enteral contrast medium and its significance as a sign of mesenteric ischaemia is discussed.  相似文献   
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BACKGROUND: The textural properties of potato tubers influence their acceptability and palatability and these properties differ between varieties, groups and progeny. The aim of this study was to compare the textural properties of cooked tubers of Solanum tuberosum group Phureja with those of group Tuberosum. RESULTS: To assess intra‐tuber differences, the textural properties of seven cubes from defined positions along the longitudinal axis of tubers of four Tuberosum group cultivars and three Phureja group lines were tested after cooking using an amended wedge fracture method. Tuberosum group tubers gave consistently higher peak force and work done values during fracture than the Phureja group tubers. Moreover, the values for cubes 1–6 from any tuber were not significantly different and only cube 7, from the stem end, gave higher values. Therefore, the use of any of cubes 1–6 is a valid measurement of the tuber as a whole but the central cube 4 may be most conveniently located. The dry matter content of the cubes did not influence the textural properties of the cubes, which suggested that starch swelling is not the main driving force for textural differences. Total pectin methyl esterase (PME) activity was consistently higher in cubes of the Tuberosum group cultivars over the Phureja group lines. CONCLUSION: The method developed is valid and consistent for assessing textural differences within potato germplasm. The relationship between PME activity and enhanced resistance to fracture suggests that PME may modulate pectin cohesiveness, perhaps through increasing Ca2+‐bridges, to provide greater resistance to fracture. Copyright © 2010 Society of Chemical Industry  相似文献   
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