28 resultados para FCP


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In this study, the background activity of beta-glucuronidase (GUS) was analyzed histochemically and fluorometrically in the negative control of Laminaria japonica (Phaeophyta) thalli, showing low level of activity. GUS gene transformation without selectable gene in L. japonica was performed using four different promoters, i.e., Cauliflower mosaic virus 35S promoter (CaMV35S) from cauliflower mosaic virus, ubiquitin promoter (UBI) from maize, adenine-methyl transfer enzyme gene promoter (AMT) from virus in green alga Chlorella, and fucoxanthin chlorophyll a/c-binding protein gene promoter (FCP) from diatom Phaeodactylum tricornutum. The GUS transient activity was determined fluorometrically after bombarding sliced parthenogenetic sporophytes explants, and it was found that the activity resulting from CaMV35S and FCP promoters (in 114.3 and 80.6 pmol MU min(-1) (mg protein)(-1), respectively) was higher than for the other two promoters. The female gametophytes were bombarded and regenerated parthenogenetic sporophytes. FCP was the only promoter that resulted in detectable GUS chimeric expression activity during histochemical staining and polymerase chain reaction. Results of Southern blot showed that GUS gene was integrated with the L. japonica genome.

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Includes bibliography.

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Back face strain (BFS) measurement is now well-established as an indirect technique to monitor crack length in compact tension (CT) fracture specimens [1,2]. Previous work [2] developed empirical relations between fatigue crack propagation (FCP) parameters. BFS, and number of cycles for CT specimens subjected to constant amplitude fatigue loading. These predictions are experimentally validated in terms of the variations of mean values of BFS and load as a function of crack length. Another issue raised by this study concerns the validity of assigning fixed values for the Paris parameters C and n to describe FCP in realistic materials.

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We describe a compiler for the Flat Concurrent Prolog language on a message passing multiprocessor architecture. This compiler permits symbolic and declarative programming in the syntax of Guarded Horn Rules, The implementation has been verified and tested on the 64-node PARAM parallel computer developed by C-DAC (Centre for the Development of Advanced Computing, India), Flat Concurrent Prolog (FCP) is a logic programming language designed for concurrent programming and parallel execution, It is a process oriented language, which embodies dataflow synchronization and guarded-command as its basic control mechanisms. An identical algorithm is executed on every processor in the network, We assume regular network topologies like mesh, ring, etc, Each node has a local memory, The algorithm comprises of two important parts: reduction and communication, The most difficult task is to integrate the solutions of problems that arise in the implementation in a coherent and efficient manner. We have tested the efficacy of the compiler on various benchmark problems of the ICOT project that have been reported in the recent book by Evan Tick, These problems include Quicksort, 8-queens, and Prime Number Generation, The results of the preliminary tests are favourable, We are currently examining issues like indexing and load balancing to further optimize our compiler.

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Mobile ad-hoc networks (MANETs) have recently drawn significant research attention since they offer unique benefits and versatility with respect to bandwidth spatial reuse, intrinsic fault tolerance, and low-cost rapid deployment. This paper addresses the issue of delay sensitive realtime data transport in these type of networks. An effective QoS mechanism is thereby required for the speedy transport of the realtime data. QoS issue in MANET is an open-end problem. Various QoS measures are incorporated in the upperlayers of the network, but a few techniques addresses QoS techniques in the MAC layer. There are quite a few QoS techniques in the MAC layer for the infrastructure based wireless network. The goal and the challenge is to achieve a QoS delivery and a priority access to the real time traffic in adhoc wireless environment, while maintaining democracy in the resource allocation. We propose a MAC layer protocol called "FCP based FAMA protocol", which allocates the channel resources to the needy in a more democratic way, by examining the requirements, malicious behavior and genuineness of the request. We have simulated both the FAMA as well as FCP based FAMA and tested in various MANET conditions. Simulated results have clearly shown a performance improvement in the channel utilization and a decrease in the delay parameters in the later case. Our new protocol outperforms the other QoS aware MAC layer protocols.

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An apparatus of low-temperature controlling for fatigue experiments and its crack measuring system were developed and used for offshore structural steel A131 under conditions of both low temperature and random sea ice. The experimental procedures and data processing were described, and a universal random data processing software for FCP under spectrum loading was written. Many specific features of random ice-induced FCP which differed with constant amplitude FCP behaviours were proposed and temperature effect on ice-induced FCP was pointed out with an easily neglected aspect in designing for platforms in sea ice emphasized. In the end, differences of FCP behaviours between sea ice and ocean wave were presented.

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Atomic force microscopy (AFM) and scanning electron microscopy (SEM) with cathodoluminescence (CL) were performed on exactly the same defects in a blue-emitting InGaN/GaN multiple quantum well (QW) sample enabling the direct correlation of the morphology of an individual defect with its emission properties. The defects in question are observed in AFM and SEM as a trench partially or fully enclosing a region of the QW having altered emission properties. Their sub-surface structure has previously been shown to consist of a basal plane stacking fault (BSF) in the plane of the QW stack, and a stacking mismatch boundary (SMB) which opens up into a trench at the sample surface. In CL, the material enclosed by the trench may emit more or less intensely than the surrounding material, but always exhibits a redshift relative to the surrounding material. A strong correlation exists between the width of the trench and both the redshift and the intensity ratio, with the widest trenches surrounding regions which exhibit the brightest and most redshifted emission. Based on studies of the evolution of the trench width with the number of QWs from four additional MQW samples, we conclude that in order for a trench defect to emit intense, strongly redshifted light, the BSF must be formed in the early stages of the growth of the QW stack. The data suggest that the SMB may act as a non-radiative recombination center. © 2013 American Institute of Physics.

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本文研究了如何应用GUS基因优化海带表达系统。首先研究了GUS在各种海带材料中的本底值,而后以GUS基因作为报告基因比较了几种基因工程常用启动子在海带中启动瞬间表达的效率。选择表达效率较高的真核藻类启动子与GUS基因融合,在海带中获得了稳定表达的结果。分别用组织化学染色法和荧光分析法对海带雌配子体、雄配子体、孤雌生殖海带幼孢子体和二倍体海带孢子体等四种不同的材料的GUS本底进行了检测到GUS本底。荧光分析法所得数据显示,这四种材料的GUS活性分别为3.4±0.3、5.2±0.8、14.4±1.8、12.5±1.4 (pmol MU mg~(-1) protein min~(-1)),与高等植物类似,说明GUS基因可作为报造基因用于海带基因工程研究。选用真核藻启动子FCP启动子、高等植物基因工程中常用的高效Ubi启动子和CaMV35S启动子,与GUS基因融合构建四种质粒,通过基因松的方法转化孤雌生殖海带幼孢子体,比较GUS基因在海带中的瞬间表达量。实验结果表明,与CaMV35S和FCP融合的GUS基因在海带中表达效率较高。采用基因松的方法用FCP启动子-GUS基因转化海带雌配子体,通过诱导孤雌生殖获得孤雌生殖海带幼孢子体,用组织染色法检测到了GUS活性,并从海带的总DNA扩增到了FCP启动子-GUS基因的特征条带,从而提示了FCP启动子能引导外源基因在海带中稳定表达。为了找寻高效筛选元件进行孤雌生殖海带对草丁膦的敏感性实验,用统计学的方法得出了草丁膦对不同长度孤雌海带的半致死剂量。研究发现海带全长0.5-1.6cm范围内,草丁膦的LD_(50)与海带长度不相关,同时发现浓度在2-5μg/ml狭小范围内的草丁膦对孤雌海带比高浓度具有更为明显的毒性反应。本文结果提示草丁膦抗性基因-bar基因有可能成为海带基因工程更为理想的选择标记,因为海带对草丁膦比对氯霉素和潮霉素更敏感,而后两者是目前采用的筛选压力。本文结果为海带表达系统的优化,提供了有效的报告基因、启动子和选择标记元件。

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Salmonella enterica sérovar Typhi (S. Typhi) est l’agent responsable de la fièvre typhoïde et cause environ 200 000 morts et 27 millions de cas annuellement. C’est un pathogène entérique dont le réservoir est restreint à l’Homme. Les raisons de cette restriction d’hôte sont méconnues et pourraient dépendre de l’expression de facteurs d’adhésion à des étapes importantes au cours de la pathogenèse. L’annotation bioinformatique du génome de S. Typhi identifie 12 fimbriae de type chaperon-placier (FCP), un curli ainsi qu’un pilus de type IV. L’objectif de ce projet de recherche est d’étudier ces systèmes d’adhésion peu caractérisés. D’abord, le niveau d’expression de ces gènes a été évalué dans différentes conditions de culture in vitro en utilisant une approche de gènes rapporteurs. L’expression des 14 systèmes d’adhésion a été détectée. Nos résultats indiquent qu’une carence en fer favorise l’expression des opérons bcf et csg. Indépendamment du fer, l’expression de bcf, csg, pil, sef, sta, stc, stg et sth est influencée par la richesse nutritive du milieu. L’incubation en milieu LB liquide favorise l’expression de la plupart des systèmes d’adhésion par rapport à un milieu LB liquide sans agitation ou un milieu LB solide. En somme, l’expression des systèmes d’adhésion de S. Typhi a été observée et est influencée par des conditions environnementales. Dans un second volet, nous avons tent de surexprimer les différents systèmes d’adhésion chez une souche d’E. coli ou de S. Typhi afimbriaire. Avec cette approche, nous avons été en mesure de démontrer que l’opéron tcf encode pour un fimbria fonctionnel que l’on a pu observer en microscopie électronique. L’expression de tcf chez une souche afimbriaire d’E. coli et S. Typhi a également diminué leur capacité d’adhésion à des cellules épithéliales intestinales humaines lors d’essais in vitro. Nos observations démontrent que l’expression des systèmes d’adhésion retrouvés chez S. Typhi est influencée par les conditions enviroi9onnementales. Au moins un de ces systèmes est fonctionnel. Ceci suggère une contribution des systèmes d’adhésion retrouvés chez S. Typhi lors de l’interaction de ce pathogène avec l’humain.

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The doctoral thesis focuses on the Studies on fuzzy Matroids and related topics.Since the publication of the classical paper on fuzzy sets by L. A. Zadeh in 1965.the theory of fuzzy mathematics has gained more and more recognition from many researchers in a wide range of scientific fields. Among various branches of pure and applied mathematics, convexity was one of the areas where the notion of fuzzy set was applied. Many researchers have been involved in extending the notion of abstract convexity to the broader framework of fuzzy setting. As a result, a number of concepts have been formulated and explored. However. many concepts are yet to be fuzzified. The main objective of this thesis was to extend some basic concepts and results in convexity theory to the fuzzy setting. The concept like matroids, independent structures. classical convex invariants like Helly number, Caratheodoty number, Radon number and Exchange number form an important area of study in crisp convexity theory. In this thesis, we try to generalize some of these concepts to the fuzzy setting. Finally, we have defined different types of fuzzy matroids derived from vector spaces and discussed some of their properties.

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Teniendo en cuenta los importantes aportes efectuados desde los estudios académicos a los procesos de reforma administrativa, la importancia de las reformas administrativas en un mundo cada vez más globalizado y la necesidad de profundizar en las reformas administrativas de las entidades territoriales, este trabajo de investigación tiene por objeto analizar el marco conceptual, normativo y jurisprudencial de las reformas administrativas, estudiando con detalle sus limitaciones y su control, particularmente para el caso de las entidades territoriales en Colombia. De este modo, con ocasión de esta investigación se busca identificar de forma clara el panorama sobre aquellos aspectos en los que las entidades territoriales tienen un mayor o menor grado de autonomía para llevar a cabo sus procesos de reforma administrativa, de tal forma que sea posible identificar algunos riesgos relevantes asociados a dicho panorama. Así, como importantes logros u objetivos de esta investigación se destacan los siguientes: (i) identificar y analizar las principales aproximaciones doctrinales realizadas a nivel mundial sobre las reformas administrativas, (ii) describir aquellos aspectos en los que las entidades territoriales tienen mayor o menor autonomía para adelantar sus procesos de reforma administrativa, (iii) analizar las clases de controles aplicables a estos procesos profundizando en aquellos aspectos que pueden generar su nulidad e (iv) identificar una serie de riesgos a los que están sometidos los procesos de reforma administrativa de las entidades territoriales en Colombia. Todo lo anterior permitirá responder con claridad la siguiente pregunta que ha sido una idea estructural a partir de la cual se ha desarrollado esta investigación: ¿Cuál es el marco conceptual, las limitaciones, los controles y los riesgos de las reformas administrativas a ser adelantadas por las entidades territoriales en Colombia?

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Este estudio de caso busca evaluar las consecuencias de la transformación de los grupos armados ilegales en Argelia para la seguridad y defensa francesa. Se analiza y explica cómo a raíz del cambio de denominación del GIA al GSPC, y este último al actual AQMI, el gobierno francés ha modificado su perspectiva sobre las amenazas hacia su Estado, conllevando a que las herramientas para la protección de su seguridad nacional presenten cambios con el objetivo de contrarrestar esos nuevos escenarios de inseguridad. Para ello se expondrán autores como Walter Laqueur Mohammed Ayoob y Barry Buzan con el fin de establecer un contexto teórico que permita avanzar hacia el objetivo de esta investigación, el cual se centra en demostrar el cambio de la política de seguridad y defensa de Francia a partir de los grupos armados ilegales en Argelia durante el periodo de 2007 a 2013.

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La Participación de las Empresas Militares Executive Outcomes y Sandline International en el conflicto de Sierra Leona fue una de las primeras veces en las que se vieron en escena a estos actores confluyendo en un nuevo orden internacional; y este estudio de caso busca determinar la manera de actuar de estas empresas y su incidencia en el conflicto. El caso de Sierra Leona es uno de los principales acercamientos a este nuevo fenómeno, que empezó a ejercer funciones que tradicionalmente le correspondían a los Estados y que han llevado a una privatización de la seguridad. Por medio de este estudio de caso se busca también determinar cuáles son las falencias y los retos que acarrean a las Empresas Militares Privadas en cuanto a su intervención en los conflictos internos. El caso de Sierra Leona es fundamental en tanto fue uno de los conflictos más intensos desarrollados en África en la década de los 90; y fue el momento en el cual las Empresas Militares Privadas empezaron a estar en la mira internacional a causa de estas intervenciones que generaron tanto críticas negativas como positivas.

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The conventional method for the assessment of acute inhalation toxicity (OECD Test Guideline 403, 1981) uses death of animals as an endpoint to identify the median lethal concentration (LC50). A new OECD Testing Guideline called the Fixed Concentration Procedure (FCP) is being prepared to provide an alternative to Test Guideline 403. Unlike Test Guideline 403, the FCP does not provide a point estimate of the LC50, but aims to identify an airborne exposure level that causes clear signs of nonlethal toxicity. This is then used to assign classification according to the new Globally Harmonized System of Classification and Labelling scheme (GHS). The FCP has been validated using statistical simulation rather than byin vivo testing. The statistical simulation approach predicts the GHS classification outcome and the numbers of deaths and animals used in the test for imaginary substances with a range of LC50 values and dose response curve slopes. This paper describes the FCP and reports the results from the statistical simulation study assessing its properties. It is shown that the procedure will be completed with considerably less death and suffering than Test Guideline 403, and will classify substances either in the same or a more stringent GHS class than that assigned on the basis of the LC50 value.