100 research outputs found

    Aging and its Distribution in Coarsening Processes

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    We investigate the age distribution function P(tau,t) in prototypical one-dimensional coarsening processes. Here P(tau,t) is the probability density that in a time interval (0,t) a given site was last crossed by an interface in the coarsening process at time tau. We determine P(tau,t) analytically for two cases, the (deterministic) two-velocity ballistic annihilation process, and the (stochastic) infinite-state Potts model with zero temperature Glauber dynamics. Surprisingly, we find that in the scaling limit, P(tau,t) is identical for these two models. We also show that the average age, i. e., the average time since a site was last visited by an interface, grows linearly with the observation time t. This latter property is also found in the one-dimensional Ising model with zero temperature Glauber dynamics. We also discuss briefly the age distribution in dimension d greater than or equal to 2.Comment: 7 pages, RevTeX, 4 ps files included, to be submitted to Phys. Rev.

    EFECTO DE ENMIENDAS ORGANICAS E INORGANICAS SOBRE LAS PROPIEDADES FISICAS Y QUIMICAS DEL SUELO EN AGROECOSISTEMAS DE LA SABANA AFRICANA OCCIDENTAL

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    Long-term agroecosystem productivity has stirred up the need to develop and implement nutrient management strategies that maintain and protect soil resources. In an attempt to address this, the current study involved the incorporation of residues of Centrosema pascuorum, Lablab purpureus and Parkia biglobosa. In addition, an inorganic fertilizer amended soil and, a maize/Lablab purpureus intercrop, along with the control (no amendment) was included. The treatments were replicated three times and the site had been under continuous cultivation for eight years in a savanna Alfisol. Soil quality (physical and chemical) indicators were examined for treatments effects. Dry macroaggregate turnover increased by 7% under C. pascuorum amended soils. This same treatment had more water-stable large microaggregates and a 40% increase in aggregated silt and clay content. Soil bulk density and saturated hydraulic conductivity reduced in nutrient management practices involving residue incorporation. However, soil organic carbon, total soil nitrogen, exchangeable Ca2+ and Mg2+ concentration were highest with soil receiving C. pascuorum. Crop residue management practices involving incorporation of C. pascuorum significantly improved soil physical and chemical properties of the study area.La productividad a largo plazo de los agroecosistemas ha estimulado el desarrollo e implementación de estrategias de manejo de nutrientes que mantengan y protejan el suelo. Para contribuir a este objetivo, el presente estudio estudio la incorporación de residuos de Centrosema pascuorum, Lablab purpureus y Parkia biglobosa. Adicionalmente se estudió el empleo de fertilizante inorgánico, cultivo intercalado de maíz/Lablab purpureus, y un control. Los tratamientos se aplicaron en un área que había estado en cultivo contínuo por ocho años (Alfisol de savana). Se evaluaron las características físicas y químicas del suelo. El recambio de macroagregados  secos se incrementó 7% en los suelos con adición C. pascuorum. Este mismo tratamiento tuvó mayor cantidad de microagregados hidro-estables y un incremento de 40% en los agregados de arcilla y limo. La densidad del suelo y la conductividad hidraúlica saturada se redujó en las prácticas que involucraban incorporación de residuos. Sin embargo, el carbono orgánico del suelo, nitrógeno total, Ca2+ intercambiable y la concentración de Mg2+ fueron más altos en el suelo que recibió C. pascuorum. La prácticas de manejo de residuos involucrando la incorporación de C. pascuorum mejoraron significativamente las propiedades físicas y químicas del suelo del área de estudio

    Dise?o, construcci?n y equipamiento del Hospital Materno Infantil El Carmen de Jun?n

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    El proyecto tiene como meta dise?ar, construir y equipar el Hospital Materno Infantil El Carmen de Jun?n de categor?a E-III, cuenta con tres objetivos de eficiencia: (i) cumplir con la fecha de t?rmino del proyecto seg?n cronograma de obra el 05 de febrero del 2020, tomando como referencia el inicio del proyecto el 02 de noviembre del 2017, (ii) cumplir con el presupuesto de S/ 148?263,232.40; y, (iii) lograr el 95% de aceptaci?n de los entregables del proyecto al momento de la transferencia al Gobierno Regional de Jun?n, y la subsanaci?n del 100 % de las No Conformidades para la recepci?n y entrega de obra. Asimismo, tiene dos objetivos relacionados con el producto: (i) instalar el equipamiento m?dico seg?n cronograma de obra el 15 de junio del 2019; y, (ii) realizar la construcci?n del Bloque 1: Bloque Cl?nico, Bloque 2: Ambulatorio y de Hospitalizaci?n, Bloque 3: Servicios Generales T?cnicos y de Soporte del Hospital, Bloque 4: Exteriores - Estacionamiento, seg?n cronograma de obra el 26 de enero del 2020

    Pre-empting aflatoxin contamination in legume and cereal farming systems in Northern Nigeria: Case study of the groundnut value chain

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    The current emphasis by the government of Nigeria on boosting . agricultural productivity requires actors of the agricultural sector to develop sustainable agro-allied technologies that could enhance the quality of crop-livestock products. Aflatoxin is reported to be a major challenge of many legume and cereal value chains with potentially negative impacts on product marketing, and the health of people and livestock. This study presents preliminary results of pre-emptive measures being undertaken by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) and national partners on the management of Aflatoxin contamination in the Groundnut Value Chain in selected States of Northern Nigeria. A combination of complementary approaches is being used to pre-empt aflatoxin contamination in the groundnut value chain. These include, the organization of Training of Trainers (ToT) workshops, development of aptitudes in the detection of aflatoxin levels, demonstration of onfarm options for managing aflatoxin contamination, production of pedagogic materials to support awareness raising campaigns, engagement of media organs to sustain awareness on the challenges of aflatoxin contamination, and evaluation of aflatoxin groundnut resistant genotypes. Above all, a total of 250 samples of groundnut and groundnut-based products have been collected from 16 out of the 19 States in Northern Nigeria to determine the prevalence and distribution of aflatoxin contamination. This paper presents progress on the outcomes of these interventions

    Understanding and Managing Aflatoxin Contamination in the Groundnut Value Chain in Nigeria

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    This manual is conceived to support awareness raising campaigns of the groundnut value chain actors in and out of the States targeted for the implementation of the USAID funded Groundnut Technology Upscaling Project in Nigeria. It is a fall-out of two capacity development events of the project - Media Training and Training of Trainers Workshops organized by ICRISAT in Kano during the first six months of project implementation in Nigeria. In view of the focus of the groundnut technology upscaling project on ensuring that farmers produce and market groundnuts free of Aflatoxins, the manual provides the general and specific information on Aflatoxin contamination and its management at all stages of the groundnut value chain. Though considered to be a basic companion document for front-line officers of partner institutions of the groundnut technology project, it can also be used by other actors of the groundnut value chain. The Manual is laid out in two parts; while Part 1 provides general and specific information required for the understanding of Aflatoxin, Part 2 focuses on the management of Aflatoxins at all stages of the groundnut value chain

    Reporting of prognostic markers: current problems and development of guidelines for evidence-based practice in the future

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    Prognostic markers help to stratify patients for treatment by identifying patients with different risks of outcome (e.g. recurrence of disease), and are important tools in the management of cancer and many other diseases. Systematic review and meta-analytical approaches to identifying the most valuable prognostic markers are needed because (sometimes conflicting) evidence relating to markers is often published across a number of studies. To investigate the practicality of this approach, an empirical investigation of a systematic review of tumour markers for neuroblastoma was performed; 260 studies of prognostic markers were identified, which considered 130 different markers

    Dalitz plot analysis of B- -> D+pi(-)pi(-)

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    We report on a Dalitz plot analysis of B- -> D+pi(-)pi(-) decays, based on a sample of about 383 x 10(6) Y(4S) -> B (B) over bar decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We find the total branching fraction of the three-body decay: B(B- -> D+ pi(-)pi(-)) = (1.08 +/- 0.03 +/- 0.05) x 10(-3). We observe the established D-2*(0) and confirm the existence of D-0*(0) in their decays to D+pi(-), where the D-2*(0) and D-0*(0) are the 2(+) and 0(+) c (u) over bar P-wave states, respectively. We measure the masses and widths of D-2*(0) and D-0*(0) to be: m(D2)*(0) = (2460.4 +/- 1.2 +/- 1.2 +/- 1.9) MeV/c(2), Gamma(D2*0) = (41.8 +/- 2.5 +/- 2.1 +/- 2.0) MeV, m(D0*0) = (2297 +/- 8 +/- 5 +/- 19) MeV/c(2), and Gamma(D0*0) = (273 +/- 12 +/- 17 +/- 45) MeV. The stated errors reflect the statistical and systematic uncertainties, and the uncertainty related to the assumed composition of signal events and the theoretical model.We are grateful for the extraordinary contributions of our PEP-II colleagues in achieving the excellent luminosity and machine conditions that have made this work possible. The success of this project also relies critically on the expertise and dedication of the computing organizations that support BABAR. The collaborating institutions wish to thank SLAC for its support and the kind hospitality extended to them. This work is supported by the US Department of Energy and National Science Foundation, the Natural Sciences and Engineering Research Council (Canada), the Commissariat à l'Energie Atomique and Institut National de Physique Nucléaire et de Physique des Particules (France), the Bundesministerium für Bildung und Forschung and Deutsche Forschungsgemeinschaft (Germany), the Istituto Nazionale di Fisica Nucleare (Italy), the Foundation for Fundamental Research on Matter (The Netherlands), the Research Council of Norway, the Ministry of Education and Science of the Russian Federation, Ministerio de Educación y Ciencia (Spain), and the Science and Technology Facilities Council (United Kingdom). Individuals have received support from the Marie-Curie IEF program (European Union) and the A. P. Sloan Foundation.Peer reviewe

    Marqueurs des cancers digestifs : côlon–rectum, pancréas, foie☆

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