1,001 research outputs found

    11β-Hydroxysteroid dehydrogenase type 2 complementary deoxyribonucleic acid stably transfected into Chinese hamster ovary cells: Specific inhibition by 11α-hydroxyprogesterone

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    The 11β-hydroxysteroid dehydrogenase type 2 (11βHSD-2) enzyme is thought to confer aldosterone specificity upon mineralocorticoid target tissues by protecting the mineralocorticoid receptor from binding by the more abundant glucocorticoids, corticosterone and cortisol. We have developed a Chinese hamster ovary cell line stably transfected with a plasmid containing the rat 11βHSD-2 complementary DNA. This cell line has expressed the enzyme consistently for many generations. The 11βHSD-2 was located primarily in the microsomes, but significant amounts also existed in the nuclei and mitochondria. The enzymatic reaction was unidirectional, oxidative, and inhibited by the product, 11-dehydrocorticosterone, with an IC50 of approximately 200 nM. The K(m) for corticosterone was 9.6 ± 3.1 nM, and that for NAD+ was approximately 8 μM. The enzyme did not convert dexamethasone to 11-dehydrodexamethasone. Tunicamycin, an N-glycosylation inhibitor, had no effect on enzyme activity, 11α-Hydroxyprogesterone (11αOH-P) was an order of magnitude more potent a competitive inhibitor of the 11βHSD-2 than was glycyrrhetinic acid (GA) (approximate IC50 0.9 vs. 15 nM). 11βOH-P, progesterone, and GA were almost equipotent (IC50 = 10 and 6 nM, respectively), and 5α-pregnandione and 5β-pregnandione were less potent (IC50 = 100 and 500 nM, respectively) inhibitors of the enzyme. When the inhibitory activities were examined with intact transfected cells, 11αOH-P was more potent than GA (IC50 = 5 and 150 nM, respectively). 11αOH-P was not metabolized by 11βHSD-2. We were unable to demonstrate the presence of 11αOH-P in human urine. In conclusion, a cell line stably transfected with the rat 11βHSD-2 was created, and the enzyme kinetics, including inhibition, were characterized. 11αOH-P was found to be a potent relatively specific inhibitor of the 11βHSD-2 enzyme. Its potential importance is that it is the most specific inhibitor of the 11βHSD-2 so far encountered and would aid in the study of the physiological importance of the isoenzyme.Fil:Cozza, E.N. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

    Reference Ontologies to Support the Development of New Product-Service Lifecycle Systems

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    In competitive and time sensitive market places, organisations are tasked with providing Product Lifecycle Management (PLM) approaches to achieve and maintain competitive advantage, react to change and understand the balance of possible options when making decisions on complex multi-faceted problems, Global Production Networks (GPN) in one such domain in which this applies. When designing and configuring GPN to develop, manufacture and deliver product-service provision, information requirements that affect decision making become more complex. The application of reference ontologies to a domain and its related information requirements can enhance and accelerate the development of new product-service lifecycle systems with a view towards the seamless interchange of information or interoperability between systems and domains. This paper present preliminary results for the capture and modelling of end-user information and an initial higher level reference core ontology for the development of reference ontologies to ameliorate product-service lifecycle management for GPNPalmer, C.; Urwin, E.; Pinazo-Sanchez, J.; Sánchez Cid, F.; Pajkovska-Goceva, S.; Young, R. (2014). Reference Ontologies to Support the Development of New Product-Service Lifecycle Systems. En Advances in Production Management Systems: Innovative and Knowledge-Based. Springer Verlag. 642-649. doi:10.1007/978-3-662-44736-9_78S642649Vandermerwe, S., Rada, J.: Servitization of business: adding value by adding services. European Management Journal 6(4), 314–324 (1988)Coe, N.M., Dicken, P., Hess, M.: Global production networks: realizing the potential. Economic Geography Research Group, Working Paper Series No. 05.07 (2007)Young, R.I.M., Gunendran, A.G., Chungoora, N., Harding, J.A., Case, K.: Enabling interoperable manufacturing knowledge sharing in PLM. In: Proceedings of the Sixth Interna-tional Conference on Product Life Cycle Management PLM 2009, University of Bath, Bath, UK, July 6-8, pp. 130–138. Inderscience Enterprises Ltd., Switzerland (2009)Chungoora, N., Young, R.I.M.: The configuration of design and manufacture know-ledge models from a heavyweight ontological foundation. International Journal of Production Research 49(15), 4701–4725 (2011)Chungoora, N., Cutting-Decelle, A.-F., Young, R.I.M., Gunendran, G., Usman, Z., Harding, J.A., Case, K.: Towards the ontology-based consolidation of production-centric standards. International Journal of Production Research 51(2), 327–345 (2013a)Hastilow, N.: An Ontological Approach to Manufacturing Systems Interoperability in Dynamic Change Environments. PhD Thesis. School of Mechanical and Manufacturing Engineering, Loughborough University, UK (2013)Highfleet Ontology Library Reference. Highfleet Inc., Baltimore (2014)International Standards Society, ISO/IEC 15288:2008 Systems and Software Engineering – System lifecycle processes. ISO, Genève (2008)Banathy, B.H.: A systems view of education: Concepts and principles for effective practice. Educational Technology (1992)OMG, 2012 OMG unified modeling language (OMG UML), superstructure and infrastructure version 2.4.1 (2012), http://www.omg.org/spec/UML/2.4.1/ (accessed May 9, 2014)Mizoguchi, R., Kozaki, K., Kitamura, Y.: Ontological analyses of roles. In: 2012 Federated Conference on Computer Science and Information Systems (FedCSIS), pp. 489–496. IEEE (September 2012)FIPS PUBs: Integration definition for function modelling (IDEF0). Federal information processing standards publication, 183 (1993)POP* Revised framework Work package – A1.8, Athena European integrated project no. 507849 public deliverable (2006

    Hybrid Intelligent Inverse Optimal Control forMethane Production in an Anaerobic Process

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    Anaerobic processes are very attractive because of their waste treatment properties and their capacity for transforming waste materials in order to generate methane, which can be used as a renewable energy source. A hybrid intelligent control strategy for an anaerobic process is proposed in this work; the structure of this strategy is as follows: a) a control law calculates dilution rate and bicarbonate addition in order to track a methaneproduction reference trajectory; this control law is based on speed-gradient inverse optimalneural control, b) a nonlinear discrete-time recurrent high-order neural observer isused to estimate biomass concentration, substrate degradation and inorganic carbon, and c) a Takagi-Sugeno supervisor, which detects the process state, selects and applies themost adequate control action, allowing a smooth switching between open loop and closed loop. The applicability of the proposed scheme is illustrated via simulations consideringa completely stirred tank reactor

    Diffusion and Localization of Cold Atoms in 3D Optical Speckle

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    In this work we re-formulate and solve the self-consistent theory for localization to a Bose-Einstein condensate expanding in a 3D optical speckle. The long-range nature of the fluctuations in the potential energy, treated in the self-consistent Born approximation, make the scattering strongly velocity dependent, and its consequences for mobility edge and fraction of localized atoms have been investigated numerically.Comment: 8 pages, 11 figure

    Modelling and Interpreting The Effects of Spatial Resolution on Solar Magnetic Field Maps

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    Different methods for simulating the effects of spatial resolution on magnetic field maps are compared, including those commonly used for inter-instrument comparisons. The investigation first uses synthetic data, and the results are confirmed with {\it Hinode}/SpectroPolarimeter data. Four methods are examined, one which manipulates the Stokes spectra to simulate spatial-resolution degradation, and three "post-facto" methods where the magnetic field maps are manipulated directly. Throughout, statistical comparisons of the degraded maps with the originals serve to quantify the outcomes. Overall, we find that areas with inferred magnetic fill fractions close to unity may be insensitive to optical spatial resolution; areas of sub-unity fill fractions are very sensitive. Trends with worsening spatial resolution can include increased average field strength, lower total flux, and a field vector oriented closer to the line of sight. Further-derived quantities such as vertical current density show variations even in areas of high average magnetic fill-fraction. In short, unresolved maps fail to represent the distribution of the underlying unresolved fields, and the "post-facto" methods generally do not reproduce the effects of a smaller telescope aperture. It is argued that selecting a method in order to reconcile disparate spatial resolution effects should depend on the goal, as one method may better preserve the field distribution, while another can reproduce spatial resolution degradation. The results presented should help direct future inter-instrument comparisons.Comment: Accepted for publication in Solar Physics. The final publication (including full-resolution figures) will be available at http://www.springerlink.co

    Tratamientos profesionales de semilla en siembra temprana: impacto en la implantaciĂłn y rendimiento en grano de soja

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    PosterEl potencial productivo de un cultivo comienza con una implantación exitosa. Los tratamientos de semilla son una práctica cada vez más difundida especialmente ante situaciones que reducen la velocidad de germinación y emergencia de plántulas, como siembras tempranas. Objetivo: evaluar el efecto de tres tratamientos profesionales de semilla sobre la emergencia de plántulas (EP), índice de verdor de hojas (SPAD) y rendimiento en soja en siembra temprana.Instituto de Fisiología y Recursos Genéticos VegetalesFil: Carrera, Constanza Soledad. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Carrera, Constanza Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios (UDEA); ArgentinaFil: Ergo, Verónica Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios (UDEA). ArgentinaFil: Ergo, Verónica Vanesa. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales. ArgentinaFil: Veas, Rodolfo Ezequiel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales. ArgentinaFil: Veas, Rodolfo Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios (UDEA). ArgentinaFil: Gaido, N.E. Syngenta. Seedcare Institute; ArgentinaFil: Bongiorni, N. Syngenta. Seedcare Institute; ArgentinaFil: Rodriguez, M.J. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Sanchez, E.N. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentin

    Micromachined Jets for Liquid Impingement Cooling of VLSI Chips

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    Small-scale solar magnetic fields

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    As we resolve ever smaller structures in the solar atmosphere, it has become clear that magnetism is an important component of those small structures. Small-scale magnetism holds the key to many poorly understood facets of solar magnetism on all scales, such as the existence of a local dynamo, chromospheric heating, and flux emergence, to name a few. Here, we review our knowledge of small-scale photospheric fields, with particular emphasis on quiet-sun field, and discuss the implications of several results obtained recently using new instruments, as well as future prospects in this field of research.Comment: 43 pages, 18 figure

    Green function techniques in the treatment of quantum transport at the molecular scale

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    The theoretical investigation of charge (and spin) transport at nanometer length scales requires the use of advanced and powerful techniques able to deal with the dynamical properties of the relevant physical systems, to explicitly include out-of-equilibrium situations typical for electrical/heat transport as well as to take into account interaction effects in a systematic way. Equilibrium Green function techniques and their extension to non-equilibrium situations via the Keldysh formalism build one of the pillars of current state-of-the-art approaches to quantum transport which have been implemented in both model Hamiltonian formulations and first-principle methodologies. We offer a tutorial overview of the applications of Green functions to deal with some fundamental aspects of charge transport at the nanoscale, mainly focusing on applications to model Hamiltonian formulations.Comment: Tutorial review, LaTeX, 129 pages, 41 figures, 300 references, submitted to Springer series "Lecture Notes in Physics
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