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71.
Secretory phospholipases A2 (sPLA2s) are implicated in the pathogenesis of several inflammation diseases, such as rheumatoid arthritis, septic shock, psoriasis, and asthma. Thus, an understanding of their inactivation mechanisms could be useful for the development of new classes of chemical selective inhibitors. In the marine environment, several bioactive terpenoids possess interesting anti‐inflammatory activity, often through covalent and/or noncovalent inactivation of sPLA2. Herein, we report the molecular mechanism of human group IIA phospholipase A2 (sPLA2‐IIA) inactivation by Scalaradial (SLD), a marine 1,4‐dialdehyde terpenoid isolated from the sponge Cacospongia mollior and endowed with a significant anti‐inflammatory profile. Our results have been collected by a combination of biochemical approaches, advanced mass spectrometry, surface plasmon resonance, and molecular modeling. These suggest that SLD acts as a competitive inhibitor. Indeed, the sPLA2‐IIA inactivation process seems to be driven by the noncovalent recognition process of SLD in the enzyme active site and by chelation of the catalytic calcium ion. In contrast, covalent modification of the enzyme by the SLD dialdehyde moiety emerges as only a minor side event in the ligand–enzyme interaction. These results could be helpful for the rational design of new PLA2 inhibitors that would be able to selectively target the enzyme active site.  相似文献   
72.
73.
Recent research on compact genetic algorithms (cGAs) has proposed a number of evolutionary search methods with reduced memory requirements. In cGAs, the evolution of populations is emulated by processing a probability vector with specific update rules. This paper considers the implementation of cGAs in microcontroller-based control platforms. In particular, to overcome some problems related to the binary encoding schemes adopted in most cGAs, this paper also proposes a new variant based on a real-valued solution coding. The presented variant achieves final solutions of the same quality as those found by binary cGAs, with a significantly reduced computational cost. The potential of the proposed approach is assessed by means of an extensive comparative study, which includes numerical results on benchmark functions, simulated and experimental microcontroller design problems.  相似文献   
74.
The goals of an organization of data and information collected from the European industrial systems and concerning networks of enterprises, mainly small-mid enterprises (SMEs), are many:
(a)
to offer an intelligent support system (ISS) to industrial analysers when they try to understand if a SME network, either cluster or industrial district, could be enforced by proper financing, or it cannot give sufficient assurance for a new development;
(b)
to offer to political people a support in understanding the dynamics of these SME networks, in order to be able to take decisions about public politics;
(c)
to give tools for analysing the performance of these industrial bodies to industrial people, mainly technicians and managers, such to be able to apply new strategies for their improvement;
(d)
to give information and data to researchers operating in university and RTD centers, such to be able to improve their knowledge about these so important industrial bodies.
To reach this goal, the aim of the EU-funded CODESNET (COllaborative DEmand & Supply NETwork) project is to give new ideas and concepts sufficient to drive the attention of the above-mentioned different types of people towards the SME networks and districts. To this aim, a crucial problem must be approached and solved: which model of a SME network should be stated and used as the basis for developing a clear and useful ISS, that is, able to collect information and data from existing SME networks and transfer such data into standard formats, easy to be read by both industrial people and scientific researchers. The present paper describes the theoretical methodology on which the data organization and interpretation adopted in the CODESNET project is based. The application of an original meta-model of SME network, developed in the mentioned project, is detailed according to the following steps. After the meta-model formulation (in Section 2), it is shown how the variables to be measured (such to have a clear understanding of the network status), have to be selected, and how the main issues concerning the design and management of the network has to be classified (Section 3). Then, it will be shown how the archive of both data/information from existing SME networks (for purpose of comparison-based analysis) and the catalogue of technical/scientific reports (for purpose of justifying the analysis considerations) has been organized in an integrated form. The scope is to give at disposal of industrial people the mentioned ISS which allow them to approach some main issues concerning the network design and management (Section 4). An example of ISS application in an Italian industrial district will be presented, such to illustrate the CODESNET results’ usefulness.  相似文献   
75.
An optimal design of Photonic Band-Gap (PBG) based resonance cavities has been carried out and optimal design rules have been drawn by a very fast and accurate computer code, developed by the authors, implementing a new model of one-dimensional finite-size PBG materials. The model also takes into account the presence of defects; it allows to accurately determine the mode propagation constants, electromagnetic harmonics and total field distribution, transmission and reflection coefficients, forward and backward power flow, guided and radiated power and total losses due to radiation, Bragg scattering and out of plane scattering. The design of resonance cavities advancing the state of the art of commercial Dense Wavelength Division Multiplexing (DWDM) filters is performed. A great number of optical cavities have been designed and quickly simulated thanks to the fastness of the code, allowing optimal design rules to be drawn.  相似文献   
76.
面向纳电子时代的非易失性存储器   总被引:1,自引:0,他引:1  
目前,业界对两大类全新的非易失性存储器进行了可行性调研,其中一类是基于无机材料的存储器技术,如铁电存储器(FeRAM)、磁阻存储器(MRAM)或相变存储器(PCM),另一类存储器技术则基于有机材料,铁电或导电开关聚  相似文献   
77.
The development of reliable fuel cells power plant based on renewable fuels stands out as one of the promising energy systems solutions for the future. Indeed fuel cells can increase the efficiency and the cleaning of the electrical energy production from renewable fuels. Process simulations of advanced power plants fed by low cost renewable fuels like biomass waste are a key step to develop renewable resources based on high temperature fuel cells applications. The aim of this work is to predict the component behaviour of a specific power plant mainly composed of a small indirectly heated gasifier and a Solid Oxide Fuel Cell (SOFC) and fed by chestnut coppice, waste available in great quantity in Central Italy, as well as in several other European regions. The plant's thermodynamic behaviour is analysed by means of the process simulator CHEMCAD© in which particular models for the SOFC and the gasifier have been developed in FORTRAN by the authors and then interfaced to commercial software. The results of the predictive model are presented and discussed, showing the possibility of an extremely interesting “carbon neutral” small plant configuration with high electrical and global efficiency exclusively based on the use of low cost renewable resources.  相似文献   
78.
The contemporary psychoanalytic concept of dissociation leads paradoxically to the conclusion that the self is both a unity and a multiplicity. Against the normative interpretations of Stern, Bromberg, and Davies, the present study conceptualizes dissociation categorically in terms of two subtypes with two distinct levels. The proposed classification scheme is consistent with the growing body of research on the subject. However, a categorical view of dissociation vitiates the soundness of the argument for normative multiplicity. In the absence of an intrinsic link to pathological dissociation, multiplicity is more parsimoniously understood without reification in terms of conflicting aims, beliefs, and feelings within an integrated self. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
79.
An atypical pyruvate kinase (PK) in erythrocytes was studied in a family with several different haematological diseases: non-spherocytic haemolysis, thrombocytopenia, myelofibrosis and polycythaemic traits. Atypical intraerythrocytic PK was also found in a group of non-related patients with myelofibrosis and polycythaemia vera. The atypical PK was characterised by abnormal urea inhibition and other relevant biochemical parameters.  相似文献   
80.
Natural or synthetic? Several petrosaspongiolide M natural and synthetic analogues have been tested as proteasome inhibitors and apoptosis modulators. The natural petrosaspongiolide M congeners gave a consistent decrease in activity. Among the synthetic analogues, the introduction of the benzothiophene ring resulted in a bioequivalent alternative of the petrosaspongiolide M terpenoid system.  相似文献   
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