49 research outputs found

    Development of a novel UPLC-MS/MS-based platform to quantify amines, amino acids and methylarginines for applications in human disease phenotyping

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    Amine quantification is an important strategy in patient stratification and personalised medicine. This is because amines, including amino acids and methylarginines impact on many homeostatic processes. One important pathway regulated by amine levels is nitric oxide synthase (NOS). NOS is regulated by levels of (i) the substrate, arginine, (ii) amino acids which cycle with arginine and (iii) methylarginine inhibitors of NOS. However, biomarker research in this area is hindered by the lack of a unified analytical platform. Thus, the development of a common metabolomics platform, where a wide range of amino acids and methylarginines can be measured constitutes an important unmet need. Here we report a novel high-throughput ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) platform where ≈40 amine analytes, including arginine and methylarginines can be detected and quantified on a molar basis, in a single sample of human plasma. To validate the platform and to generate biomarkers, human plasma from a well-defined cohort of patients before and after coronary artery bypass surgery, who developed systemic inflammatory response syndrome (SIRS), were analysed. Bypass surgery with SIRS significantly altered 26 amine analytes, including arginine and ADMA. Consequently, pathway analysis revealed significant changes in a range of pathways including those associated with NOS

    Hydrodynamic slip can align thin nanoplatelets in shear flow

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    The large-scale processing of nanomaterials such as graphene and MoS2 relies on understanding the flow behaviour of nanometrically-thin platelets suspended in liquids. Here we show, by combining non-equilibrium molecular dynamics and continuum simulations, that rigid nanoplatelets can attain a stable orientation for sufficiently strong flows. Such a stable orientation is in contradiction with the rotational motion predicted by classical colloidal hydrodynamics. This surprising effect is due to hydrodynamic slip at the liquid-solid interface and occurs when the slip length is larger than the platelet thickness; a slip length of a few nanometers may be sufficient to observe alignment. The predictions we developed by examining pure and surface-modified graphene is applicable to different solvent/2D material combinations. The emergence of a fixed orientation in a direction nearly parallel to the flow implies a slip-dependent change in several macroscopic transport properties, with potential impact on applications ranging from functional inks to nanocomposites.Energy Technolog

    Permeation, regulation and control of expression of TRP channels by trace metal ions

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    Thermal Conductivity Behavior of Yttria Nanofluids

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    ABSTRACT In this paper the effect of nanoparticle concentration and temperature on the thermal conductivity of Yttria-Ethylene glycol nanofluid has been investigated. In addition, the effect of aging on the viscosity and the thermal conductivity of these nanofluids also have been studied. The nanofluids were prepared by two-step method, and particle size distributions were characterized using acoustic spectroscopy. It was found that the thermal conductivity of Yttria nanofluids increases beyond the classical Hamilton-Crosser model. Moreover, the enhancement in the thermal conductivity of this nanofluid showed high temperature dependence behavior. For instance at 3.0% by volume particles loading, the thermal conductivity enhancement increased from 16.6% at 26 0 C to 27.0% at 59 0 C, making these nanofluids attractive and effective for cooling systems that operates at high temperatures. Finally, time dependent viscosity and thermal conductivity measurements showed stable behavior for 16 days of study demonstrating the good stability of these nanofluids

    2-Aminoethoxydiphenyl borate (2-APB) is a reliable blocker of store-operated Ca<sup>2+</sup> entry but an inconsistent inhibitor of InsP<sub>3</sub>-induced Ca<sup>2+</sup> release

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    Since its introduction to Ca2+ signaling in 1997, 2-aminoethoxydiphenyl borate (2-APB) has been used in many studies to probe for the involvement of inositol 1,4,5-trisphosphate receptors in the generation of Ca2+ signals. Due to reports of some nonspecific actions of 2-APB, and the fact that its principal antagonistic effect is on CaCa2+ entry rather than Ca2+ release, this compound may not have the utility first suggested. However, 2-APB has thrown up some interesting results, particularly with respect to store-operated Ca2+ entry in nonexcitable cells. These data indicate that although it must be used with caution, 2-APB can be useful in probing certain aspects of Ca2+ signalin

    The McNair Scholars Journal, 2001

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    The McNair Program at the University of Wisconsin-Superior prepares income eligible, first generation college students and students from groups underrepresented in graduate education for doctoral study. It is a nationwide program sponsored by the U.S. Department of Education, created in memory of Ronald E. McNair, Ph.D., an African-American physicist killed in the Space Shuttle Challenger mission in 1986. During the summer, 12 scholars participate in a paid individual research experience, working collaboratively with a faculty mentor on a project of interest to the student

    Multifaceted impacts of sustainable land management in drylands: A review

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    Biophysical restoration or rehabilitation measures of land have demonstrated to be effective in many scientific projects and small-scale environmental experiments. However circumstances such as poverty, weak policies, or inefficient scientific knowledge transmission can hinder the effective upscaling of land restoration and the long term maintenance of proven sustainable use of soil and water. This may be especially worrisome in lands with harsh environmental conditions. This review covers recent efforts in landscape restoration and rehabilitation with a functional perspective aiming to simultaneously achieve ecosystem sustainability, economic efficiency, and social wellbeing. Water management and rehabilitation of ecosystem services in croplands, rangelands, forests, and coastlands are reviewed. The joint analysis of such diverse ecosystems provides a wide perspective to determine: (i) multifaceted impacts on biophysical and socio-economic factors; and (ii) elements influencing effective upscaling of sustainable land management practices. One conclusion can be highlighted: voluntary adoption is based on different pillars, i.e. external material and economic support, and spread of success information at the local scale to demonstrate the multidimensional benefits of sustainable land management. For the successful upscaling of land management, more attention must be paid to the social system from the first involvement stage, up to the long term maintenance. © 2016 by the authors
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