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In this paper, we present OpenCOPI (Open COntext Platform Integration), a Service-Oriented Architecture-based middleware platform that supports the integration of services provided by distinct sources, ranging from services offered by simple systems to more complex services provided by context-provision middleware. OpenCOPI offers selection and composition mechanisms to, respectively, select and compose services provided by different sources, considering applications of both Quality of Service and Quality of Context requirements. It also offers an adaptation mechanism that enables to adapt the application execution due to service failures, service quality fluctuation and user mobility. OpenCOPI allows the definition of applications in a higher abstraction level by the specification of a semantic workflow that contains abstract activities. This paper illustrates the use of OpenCOPI in an application from the Gas & Oil Industry and it also shows the evaluation of the main mechanisms of OpenCOPI: the service selection, composition, adaptation and workflow execution.  相似文献   
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Abstract

The aim of this study was to synthesize the preactivated thiomer poly(acrylic acid)-cyteine-2-mercaptonicotinic acid (PAA-Cys-2MNA) and to evaluate its P-glycoprotein (P-gp) inhibitory properties. The thiomer (PAA-Cys) was synthesized by covalent immobilization of thiol groups on poly(acrylic acid) (PAA) with a molecular mass of 250?kDa followed by immobilization of 2-mercaptonicotinic acid (2MNA) to thiol groups via disulfide bond formation resulting in PAA-Cys-2MNA. P-gp inhibitory effect of this preactivated thiomer was evaluated on Caco-2 cells. Transports of rhodamine 123 at 37?°C with and without verapamil and at 4?°C were performed to evaluate P-gp function of cells. In total, 1571.81?±?156.18?µmol thiol groups were immobilized per gram of polymer that were in the next step by 99.88% preactivated. The enhancement ratios of Papp calculated from the ratio between Papp of rhodamine 123 in the presence of P-gp inhibitors and Papp of rhodamine 123 alone were 2.36, 2.09, and 1.84-fold in the presence of PAA-Cys-2MNA, PAA-Cys, and PAA, respectively. Because of its pronounced P-gp inhibitory effect, PAA-Cys-2MNA could be considered as promising macromolecular P-gp inhibitor for various drug delivery systems.  相似文献   
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The last decade has seen remarkable advances in the development of drug delivery systems as alternative to parenteral injection‐based delivery of insulin. Neonatal Fc receptor (FcRn)‐mediated transcytosis has been recently proposed as a strategy to increase the transport of drugs across the intestinal epithelium. FcRn‐targeted nanoparticles (NPs) could hijack the FcRn transcytotic pathway and cross the epithelial cell layer. In this study, a novel nanoparticulate system for insulin delivery based on porous silicon NPs is proposed. After surface conjugation with albumin and loading with insulin, the NPs are encapsulated into a pH‐responsive polymeric particle by nanoprecipitation. The developed NP formulation shows controlled size and homogeneous size distribution. Transmission electron microscopy (TEM) images show successful encapsulation of the NPs into pH‐sensitive polymeric particles. No insulin release is detected at acidic conditions, but a controlled release profile is observed at intestinal pH. Toxicity studies show high compatibility of the NPs with intestinal cells. In vitro insulin permeation across the intestinal epithelium shows approximately fivefold increase when insulin is loaded into FcRn‐targeted NPs. Overall, these FcRn‐targeted NPs offer a toolbox in the development of targeted therapies for oral delivery of insulin.  相似文献   
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Given a Feynman parameter integral, depending on a single discrete variable NN and a real parameter εε, we discuss a new algorithmic framework to compute the first coefficients of its Laurent series expansion in εε. In a first step, the integrals are expressed by hypergeometric multi-sums by means of symbolic transformations. Given this sum format, we develop new summation tools to extract the first coefficients of its series expansion whenever they are expressible in terms of indefinite nested product–sum expressions. In particular, we enhance the known multi-sum algorithms to derive recurrences for sums with complicated boundary conditions, and we present new algorithms to find formal Laurent series solutions of a given recurrence relation.  相似文献   
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This work investigates the horizontal and web shear resistance of continuous and discontinuous slab-web connections in pre-cast pre-tensioned bridge systems. The beams were full scale pre-cast pre-tensioned girders and the slabs were made of ordinary reinforced concrete either cast in place, for continuous connections, or pre-cast slabs with holes spaced at 312.5 mm to be set in place, for discontinuous connections. The main variables were the connection type (continuous or discontinuous) and the ratio of the connection steel. From the test results and the numerical analysis performed, a modified stress field for the inclined compressive strut in the truss model is proposed for continuous and discontinuous slab-web connections. The analytical results obtained with the proposed modified stress field in the truss model compared well with the tests results. Design procedures for these types of elements are also discussed.  相似文献   
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The architecture of a modern building is viewed and defined as a whole: the so-called decorative detail does not exist, only the intelligent and strictly controlled technical detail. The aesthetic basis—both social and technical at the same time—of modern architecture is reproduced in the three-dimensional composition.1  相似文献   
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The purpose of this study was to investigate the trans fatty acids (TFA) content and distribution in colostrum, mature milk, and diet of adolescent mothers, after TFA declaration in food labels became mandatory in Brazil. Participants were healthy adolescents (n 54, 15–19 years, 1–90 days postpartum) practicing exclusive breastfeeding. Milk samples were collected 3 days after delivery (colostrum) and in the third month postpartum (mature milk) by hand expression. The fatty acid composition of the milk samples was determined by gas chromatography. TFA intake corresponded to 1.23 % of total energy value. Total 18:2 TFA accounted for less than 0.5 % of the energy intake. The amount of total 18:1 TFA (mean ± SEM) was 1.9 % ± 0.14 in colostrum and 1.5 % ± 0.2 in mature milk. The total content of n‐3 PUFA was inversely correlated with the total content of 18:1 TFA in colostrum. Both in colostrum and in mature milk, vaccenic acid (11t‐18:1) was found to be the most abundant 18:1 trans isomer, followed by elaidic acid (9t‐18:1), whereas rumenic acid (9c,11t‐18:2 CLA) was the predominant 18:2 trans isomer. In conclusion, the levels of TFA of industrial sources found in the mother's diet and breast milk (colostrum and mature milk) showed a decrease in relation to those observed in studies conducted prior to the TFA labeling resolution in Brazil. However, the current low intake levels of n‐3 LCPUFA and DHA content in the milk of lactating adolescents may be insufficient for supporting adequate neurological development of the infants.  相似文献   
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The purpose of the article is to provide some evidence on the interconnection between capital structure, R&D investment and ownership concentration using a unique panel data-set of Italian firms. We study the effect of R&D intensity on leverage for two groups of firms which are different in terms of their degree of ownership concentration. Our results suggest for Public Limited Companies, a nonlinear relationship between R&D intensity and leverage, with the latter first increasing and then decreasing. Interestingly, the same result is not found to hold true for Private Limited Companies, which are characterized by a more concentrated ownership.  相似文献   
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