23 research outputs found

    On Weakening Conditions for Discrete Maximum Principles for Linear Finite Element Schemes.

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    In this work we discuss weakening requirements on the set of sufficient conditions due to Ph. Ciarlet [4,5] for matrices associated to linear finite element schemes, which is commonly used for proving validity of discrete maximum principles (DMPs) for the second order elliptic problems. © Springer-Verlag Berlin Heidelberg 2009

    Universal Grid client: Grid Operation Invoker

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    In this paper we present a high-level approach to programming applications which use the Grid from the client side. This study is devoted to resolving the need for a language that would allow expressing the application logic in a precise way and combining it with the capability of remote access to powerful Grid resources and complex computational software. We introduce the concept of a universal Grid client - a Grid Operation Invoker (GOI). It provides a client-side interface to computational resources that use various middleware packages within a high-level scripting language. The system prototype is written in JRuby which is a Java implementation of a popular object-oriented scripting language interpreter - Ruby. We also present issues that have emerged in the course of work on GOI and which we have found challenging. Finally, we discuss Grid applications implemented in JRuby, proving that GOI can be used to solve highly complicated and computationally-intensive problems

    Distribution and chemical coding patterns of cocaine- and amphetaminer-egulated transcript - like immunoreactive (CART - LI) neurons in the enteric nervous system of the porcine stomach cardia

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    The aim of this study was to determine the presence of cocaine- and amphetamine-regulated transcript-like immunoreactive (CART-LI) neurons and co-localisation of CART with vesicular acetylcholine transporter (VAChT), neuronal nitric oxide synthase (n-NOS), vasoactive intestinal polypeptide (VIP), substance P (SP) and leu-enkephalin (LENK) in the enteric nervous system of the porcine gastric cardia by using a double-labelling immunofluorescence technique. CART-LI neurons were observed in the myenteric plexus (18.2}2.6%). A dense network of CART-LI nerve fibers was mainly observed in the muscular layer. CART showed co-localization mainly with VAChT, n-NOS, VIP and to a lesser degree with LENK and SP. Distribution of CART and its co- ocalization with other neurotransmitters suggest that this peptide plays an important role in gastric motility in the pig

    InterPACK2011-52122 DEVELOPMENT OF MICRO/NANO ENGINEERED WICK-BASED PASSIVE HEAT SPREADERS FOR THERMAL MANAGEMENT OF HIGH POWER ELECTRONIC DEVICES

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    ABSTRACT Spreading of high-flux electronics heat is a critical part of any packaging design. This need is particularly profound in advanced devices where the dissipated heat fluxes have been driven well over 100W/cm 2 . To address this challenge, researchers at Raytheon, Thermacore and Purdue are engaged in the development and characterization of a low resistance, coefficient of thermal expansion (CTE)-matched multi-chip vapor chamber heat spreader, which utilizes capillary driven two-phase heat transport. The vapor chamber technology under development overcomes the limitations of state-of-the-art approaches by combining scaled-down sintered Cu powder and nanostructured materials in the vapor chamber wick to achieve low thermal resistance. Cu-coated vertically aligned carbon nanotubes is the nanostructure of choice in this development. Unique design and construction techniques are employed to achieve CTE-matching with a variety of device and packaging materials in a low-profile form-factor. This paper describes the materials, design, construction and characterization of these vapor chambers. Results from experiments conducted using a unique high-heat flux capable 1DSS test facility are presented, exploring the effects of various microscopic wick configurations, CNTfunctionalizations and fluid charges on thermal performance. The impacts of evaporator wick patterning, CNT evaporator functionalization and CNT condenser functionalization on performance are assessed and compared to monolithic Cu wick configurations. Thermal performance is explained as a function of applied heat flux and temperature through the identification of dominant component thermal resistances and heat transfer mechanisms. Finally, thermal performance results are compared to an equivalent solid conductor heat spreader, demonstrating a >40% reduction in thermal resistance. These results indicate great promise for the use of such novel vapor chamber technology in thickness-constrained high heat flux device packaging applications

    Bisphenol A alters β-hCG and MIF release by human placenta: an in vitro study to understand the role of endometrial cells

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    A proper fetomaternal immune-endocrine cross-talk in pregnancy is fundamental for reproductive success. This might be unbalanced by exposure to environmental chemicals, such as bisphenol A (BPA). As fetoplacental contamination with BPA originates from the maternal compartment, this study investigated the role of the endometrium in BPA effects on the placenta. To this end, in vitro decidualized stromal cells were exposed to BPA 1 nM, and their conditioned medium (diluted 1 : 2) was used on chorionic villous explants from human placenta. Parallel cultures of placental explants were directly exposed to 0.5 nM BPA while, control cultures were exposed to the vehicle (EtOH 0.1%). After 24-48 h, culture medium from BPA-treated and control cultures was assayed for concentration of hormone human Chorionic Gonadotropin ( β -hCG) and cytokine Macrophage Migration Inhibitory Factor (MIF). The results showed that direct exposure to BPA stimulated the release of both MIF and β -hCG. These effects were abolished/diminished in placental cultures exposed to endometrial cell-conditioned medium. GM-MS analysis revealed that endometrial cells retain BPA, thus reducing the availability of this chemical for the placenta. The data obtained highlight the importance of in vitro models including the maternal component in reproducing the effects of environmental chemicals on human fetus/placenta

    Bisphenol A Alters β-hCG and MIF Release by Human Placenta: An In Vitro Study to Understand the Role of Endometrial Cells

    No full text
    A proper fetomaternal immune-endocrine cross-talk in pregnancy is fundamental for reproductive success. This might be unbalanced by exposure to environmental chemicals, such as bisphenol A (BPA). As fetoplacental contamination with BPA originates from the maternal compartment, this study investigated the role of the endometrium in BPA effects on the placenta. To this end, in vitro decidualized stromal cells were exposed to BPA 1 nM, and their conditioned medium (diluted 1 : 2) was used on chorionic villous explants from human placenta. Parallel cultures of placental explants were directly exposed to 0.5 nM BPA while, control cultures were exposed to the vehicle (EtOH 0.1%). After 24–48 h, culture medium from BPA-treated and control cultures was assayed for concentration of hormone human Chorionic Gonadotropin (β-hCG) and cytokine Macrophage Migration Inhibitory Factor (MIF). The results showed that direct exposure to BPA stimulated the release of both MIF and β-hCG. These effects were abolished/diminished in placental cultures exposed to endometrial cell-conditioned medium. GM-MS analysis revealed that endometrial cells retain BPA, thus reducing the availability of this chemical for the placenta. The data obtained highlight the importance of in vitro models including the maternal component in reproducing the effects of environmental chemicals on human fetus/placenta
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