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Specific Configuration (specific + configuration)
Selected AbstractsA Theory of Migration as a Response to Relative DeprivationGERMAN ECONOMIC REVIEW, Issue 2 2000Oded Stark We model migration as a response to relative deprivation. We present a specific configuration of incomes in which the process of migration in response to relative deprivation reaches a steady state. However, for the general configuration of incomes we show that it is impossible to prove the existence of a steady state. We study the social welfare implications of the two cases and show that if individuals are left to pursue their betterment, the resulting state falls short of the best social outcome. We present several implications of the model including federalism and the demand for secession. [source] CAT4 (Cable Actuated Truss,4 Degrees of Freedom): A Novel 4 DOF Cable Actuated Parallel ManipulatorJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 12 2002Craig Kossowski The CAT4 (Cable Actuated Truss,4 degrees of freedom) robot is a novel, passively jointed, parallel robot utilizing six control cables for actuation. The architecture has been under development at the Queen's University Robotics Laboratory. The robot utilizes a passive jointed linkage with 18 revolute joints to constrain the end effector motion and provide the desired structural stability, restricting the end effector to 3 translational degrees of freedom (DOF) and 1 DOF for end effector pitch. This central mechanism together with winched cable actuation gives a number of important benefits for applications where the advantages of a parallel robot are required in conjunction with light weight. Six electric motor driven winches control the length of the cable actuators that extend from the top frame to points on the end effector raft and jointed linkage to create a stiff, but lightweight, actuated robot. Simulation work on the robot is presented giving the kinematics, including a computational estimate of the workspace for a specific configuration. Results of computational simulation of the motion of the manipulator and a discussion of the advantages and potential difficulties are also presented. © 2002 Wiley Periodicals, Inc. [source] A Review of Outcome Measures in Early Childhood ProgramsJOURNAL OF POLICY AND PRACTICE IN INTELLECTUAL DISABILITIES, Issue 4 2006Hasheem Mannan Abstract, The authors undertook a review of measures available for assessing outcomes of early childhood services for children with disabilities and their families. With principles of family-centered practice mandating the inclusion of both family and child outcome measures in effective evaluation plans, the review examined measures with established psychometric properties for (a) documenting the effectiveness of partnerships with families, and (b) documenting the effectiveness of services and supports for families. Constructs and their associated measures related to partnerships include satisfaction with the overall program and empowerment. The constructs for outcomes of supports and services include social support, parenting, and family quality of life. The authors reviewed measures for each of the five constructs. They note that the selection of appropriate measures to assess the outcomes of family support and services depends on the specific configuration of support services provided by the program and that each program may have to be explicit about the outcomes it wants to impact and therefore measure. [source] Chromatin Configurations in the Ferret Germinal Vesicle that Reflect Developmental Competence for In Vitro MaturationREPRODUCTION IN DOMESTIC ANIMALS, Issue 2 2009X Sun Contents In several mammalian species, the configuration of germinal vesicle (GV) chromatin correlates with the developmental competence of oocytes. Yet, no study has been published on the configuration of GV chromatin in ferret, nor is it known whether a specific configuration predicts meiotic competence in this species, in spite of the potential importance of ferret cloning to the study of human disease and to species conservation efforts. Here, we report on an analysis of the chromatin configuration in ferret GV oocytes and on how they correlate with meiotic development. Three distinct configurations were identified based on the degree of chromatin condensation: (1) fibrillar chromatin (FC), featuring strands of intertwined chromatin occupying most of the visible GV region; (2) intermediate condensed chromatin (ICC), characterized by dense, irregular chromatin masses throughout the GV; and (3) condensed chromatin (CC), which is highly compact and centered around the nucleolus. We also found that chromatin configuration was related to the extent of association with cumulus cells in cumulus,oocyte complexes; CC-configured oocytes were most often surrounded by a compact cumulus layer and also a compact corona but FC-configured oocytes were associated with neither. In addition, increasing chromatin condensation corresponded to an increase in oocyte diameter. Finally, following in vitro culture, significantly more CC-configured oocytes underwent maturation to meiotic metaphase II than did FC- or ICC-configured oocytes. We conclude that, in ferret, chromatin condensation is related to the sequential achievement of meiotic competencies during oocyte growth and differentiation, and thus can be used as a predictor of competence. [source] Technical characterization of an ultrasound source for noninvasive thermoablation by high-intensity focused ultrasoundBJU INTERNATIONAL, Issue 3 2002K.U. Köhrmann Objective,To develop a generator for high-intensity focused ultrasound (HIFU, a method of delivering ultrasonic energy with resultant heat and tissue destruction to a tight focus at a selected depth within the body), designed for extracorporeal coupling to allow various parenchymal organs to be treated. Material and methods,The ultrasound generated by a cylindrical piezo-ceramic element is focused at a depth of 10 cm using a parabolic reflector with a diameter of 10 cm. A diagnostic B-mode ultrasonographic transducer is integrated into the source to allow the focus to be located in the target area. The field distribution of the sound pressure was measured in degassed water using a needle hydrophone. An ultrasound-force balance was used to determine the acoustic power. These measurements allowed the spatially averaged sound intensity to be calculated. The morphology and extent of tissue necrosis induced by HIFU was examined on an ex-vivo kidney model. Results,The two-dimensional field distribution resulted in an approximately ellipsoidal focus of 32×4 mm (, 6 dB). The spatially maximum averaged sound intensity was 8591 W/cm2 at an electrical power of 400 W. The lesion caused to the ex-vivo kidney at this maximum generator power with a pulse duration of 2 s was a clearly delineated ellipsoidal coagulation necrosis up to 8.8×2.3 mm (length×width) and with central liquefied necrosis of 7.9×1.9 mm. Conclusion,This newly developed ultrasound generator with a focal length of 10 cm can induce clear necrosis in parenchymal tissue. Because of its specific configuration and the available power range of the ultrasound generator, there is potential for therapeutic noninvasive ablation of tissue deep within a patient's body. [source] The role of migrant networks in linking local labour markets: the case of Asian Indian migration to New York and LondonGLOBAL NETWORKS, Issue 3 2001Maritsa V. Poros Social networks have long been identified as crucial to migration flows and the economic behaviour of immigrants. Much of the literature on international migration and economic sociology specifically focuses on the role of interpersonal ties in influencing migration and economic action, such as finding employment. Using the case of Gujarati Indian migration to New York and London, the life histories of these immigrants illustrate that specific configurations of network ties result in different migration flows and occupational outcomes. These configurations include organizational, composite, and interpersonal ties that link local labour markets transnationally and channel immigrants to particular destinations and into particular occupations. The findings clarify the role and meaning of networks as they affect different types of migration and the occupational outcomes of migrants. The prominence of these network mechanisms also challenges the role of human capital in producing distinct outcomes for immigrants. [source] Gene positional changes relative to the nuclear substructure during carbon tetrachloride-induced hepatic fibrosis in ratsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 6 2004Apolinar Maya-Mendoza Abstract In the interphase nucleus the DNA of higher eukaryotes is organized in loops anchored to a substructure known as the nuclear matrix (NM). The topological relationship between gene sequences located in the DNA loops and the NM appears to be very important for nuclear physiology because processes such as replication, transcription, and processing of primary transcripts occur at macromolecular complexes located at discrete sites upon the NM. Mammalian hepatocytes rarely divide but preserve a proliferating capacity that is displayed in vivo after specific stimulus. We have previously shown that transient changes in the relative position of specific genes to the NM occur during the process of liver regeneration after partial ablation of the liver, but also that such changes correlate with the replicating status of the cells. Moreover, since chronic exposure to carbon tetrachloride (CCl4) leads to bouts of hepatocyte damage and regeneration, and eventually to non-reversible liver fibrosis in the rat, we used this animal model in order to explore if genes that show differential activity in the liver change or modify their relative position to the NM during the process of liver fibrosis induction. We found that changes in the relative position of specific genes to the NM occur during the chronic administration of CCl4, but also that such changes correlate with the proliferating status of the hepatocytes that goes from quiescence to regeneration to replicative senescence along the course of CCl4 -induced liver fibrosis, indicating that specific configurations in the higher-order DNA structure underlie the stages of progression towards liver fibrosis. © 2004 Wiley-Liss, Inc. [source] Asymmetric Syntheses Aided by BiocatalystsCHINESE JOURNAL OF CHEMISTRY, Issue 8 2003Pei-Ran This article summarizes the achievements of the authors' group in the area of biocatalyst-catalyzed organic reactions in recent 10 years. A strain of Geotrichum sp. obtained by screening is capable of stereoselectively reducing a number of carbonyl compounds. In many cases, the stereochemistry is complementary with that obtained by baker' s yeast. Therefore, this microorganism provides a useful pathway to the preparation of alcohol compounds with specific configurations. On the other hand, a number of plant sources have been screened for oxynitrilases and the hydrocyanation reactions of various arylcarboxaldehydes have been investigated. A "micro-aqueous reaction system" was invented, by which a series of novel optically active cyanohydrins were prepared. On this basis, a high through-put continuous reaction system has been designed. This paper also describes examples of the syntheses of bio-active compounds by using the optically active compounds obtained from the above-mentioned catalytic reactions as precursors. [source] | ||||||||||