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91.
Poly-histidine peptides such as H6(HHHHHH)are used in protein biotechnologies as purification tags,protein-assembling agents and endosomal-escape entities.The pleiotropic properties of such peptides make them appealing to design protein-based smart materials or nanoparticles for imaging or drug delivery to be produced in form of recombinant proteins.However,the clinical applicability of H6-tagged proteins is restricted by the potential immunogenicity of these segments.In this study,we have explored several humanized histidine-rich peptides in tumor-targeted modular proteins,which can specifically bind and be internalized by the target cells through the tumoral marker CXCR4.We were particularly interested in exploring how protein purification,self-assembling and endosomal escape perform in proteins containing the variant histidine-rich tags.Among the tested candidates,the peptide H5 E(HEHEHEHEH)is promising as a good promoter of endosomal escape of the associated fulllength protein upon endosomal internalization.The numerical modelling of cell penetration and endosomal escape of the tested proteins has revealed a negative relationship between the amount of protein internalized into target cells and the efficiency of cytoplasmic release.This fact demonstrates that the His-mediated,proton sponge-based endosomal escape saturates at moderate amounts of internalized protein,a fact that might be critical for the design of protein materials for cytosolic molecular delivery.  相似文献   
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In this research, ultrasonic pulse echo measurements are used to quantify through thickness chemical degradation in thin mortar specimens. The degradation level is predicted using the time of travel of the acoustic wave through the thickness of the structure. The front and back wall interaction reflections are used to obtain additional information from very early stage degradation. The pulse-velocity of sound waves as a function of the thickness of the layers within the structure is described. With knowledge of the pulse-velocity in pristine and fully degraded conditions, it is possible to determine the complete range of degradation length over the layer thickness. The method is applicable for leaching of calcium and acidic attack. The acoustic measurements were verified with destructive testing. The correlation between the acoustic and non-acoustic experiments agree with the described pulse-velocity and degraded depth function. The method based on ultrasonic measurements can be implemented in other thin-layered structures.  相似文献   
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This paper proposes a view-invariant gait recognition algorithm, which builds a unique view invariant model taking advantage of the dimensionality reduction provided by the Direct Linear Discriminant Analysis (DLDA). Proposed scheme is able to reduce the under-sampling problem (USP) that appears usually when the number of training samples is much smaller than the dimension of the feature space. Proposed approach uses the Gait Energy Images (GEIs) and DLDA to create a view invariant model that is able to determine with high accuracy the identity of the person under analysis independently of incoming angles. Evaluation results show that the proposed scheme provides a recognition performance quite independent of the view angles and higher accuracy compared with other previously proposed gait recognition methods, in terms of computational complexity and recognition accuracy.  相似文献   
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The effluents of ink-manufacturing processes contain a large variety of pollutants such as dyes, surfactants, biocides, water soluble solvents, etc. In this work, the electrochemical oxidation of several dyes (methylene blue and rhodamine B), solvents (monoethylene glycol, diethylene glycol and glycerol) and surfactants (sodium dodecylbenzenesulfonate) has been studied. To carry out the electrolyses, a bench-scale plant with a single-compartment electrochemical flow-cell was used. Boron doped diamond (BDD) was used as anode and stainless steel (AISI 304) as cathode. For all the compounds tested, the conductive diamond electrooxidation allows achieving the almost complete removal of COD of the waste with a very high current efficiency. The efficiencies of the electrochemical processes seem to depend on the current density and on the nature of the anions contained in the waste (chlorine, sulphate, phosphate). Thus, it has been observed that the use of chloride media favours the treatment of dyes. On the contrary, the use of sulphate- or phosphate-containing solutions improves the removal of the aliphatic compounds studied (solvents). These results suggest an important role of the mediated electrochemical processes on the overall performance of the reaction system.  相似文献   
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FASANT is a computer tool for the analysis of antennas on-board satellites, ships, aircraft, and other complex bodies. The structure under analysis, which can be metallic or dielectric (with and/or without losses), must be modeled by plane and/or curved surfaces. The geometrical input files are in DXF format, and can be generated by the most commonly used computer-aided geometrical-design (CAGD) tools. The code can also be applied to the analysis of arrays and arbitrarily shaped reflectors. The kernel of the code is based on the uniform theory of diffraction (UTD). Special algorithms have been developed to speed up the ray-tracing computation for both flat and curved surfaces. FASANT can obtain far-field patterns, field levels at points near the structure, can calculate the mutual coupling between antennas or between array elements, and can show each ray-tracing mechanism  相似文献   
97.
Summary. In a multi-party transaction (also called a distributed commerce transaction) agents face risks from dealing with untrusted agents. These risks are compounded in the face of deadlines, e.g., an agent may fail to deliver purchased goods by the time the goods are needed. We characterize the risks, and present a distributed algorithm that mitigates these risks, by using pairwise exchanges and trusted intermediaries. The algorithm generates a safe sequence of actions that completes a commerce transaction without risk, if such a sequence exists. We show that the algorithm is sound (produces only safe multi-agent action sequences) and complete (finds a safe sequence whenever one exists). The initial restriction of guaranteeing safety even when none of the principals trusts another can be relaxed in some cases, so we show how to handle principals that do trust each other and interact directly rather than through a trusted intermediary. Received: September 1997 / Accepted: December 1998  相似文献   
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