469 research outputs found

    Radiative corrections to the three-body region of the Dalitz plot of baryon semileptonic decays with angular correlation between polarized emitted baryons and charged leptons: The initial-baryon rest frame case

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    We complement the results for the radiative corrections to the s2.l angular correlation of baryon semileptonic decays of Ref. [1] with the final results in the rest frame of the decaying baryon.Comment: 7 pages, Revtex4, no figure

    Radiative corrections to the Dalitz plot of K_{l3}^\pm decays

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    We calculate the model-independent radiative corrections to the Dalitz plot of K_{l3}^\pm decays to order (\alpha/\pi)(q/M_1), where q is the momentum transfer and M_1 is the mass of the kaon. The final results are presented, first, with the triple integration over the variables of the bremsstrahlung photon ready to be performed numerically and, second, in an analytical form. These two forms are useful to crosscheck on one another and with other calculations. This paper is organized to make it accessible and reliable in the analysis of the Dalitz plot of precision experiments and is not compromised to fixing the form factors at predetermined values. It is assumed that the real photons are kinematically discriminated. Otherwise, our results have a general model-independent applicability.Comment: RevTex4, 38 pages, 5 figures, 5 tables; some typos corrected; discussion extended to compare with other result

    Planar measurements of spray-induced wall cooling using phosphor thermometry

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    The wall cooling induced by spray impingement is investigated using phosphor thermometry. Thin coatings of zinc oxide (ZnO) phosphor were applied with a transparent chemical binder onto a steel surface. Instantaneous spatially resolved temperatures were determined using the spectral intensity ratio method directly after the injection of UV-grade hexane onto the surface using a commercial gasoline injector. The investigations showed that 2D temperature measurements with high spatial and shot-to-shot precision of, respectively, 0.5 and 0.6 K can be achieved, allowing the accurate resolution of the cooling induced by the spray. The presence of a liquid film over the phosphor coating during measurements showed no noticeable influence on the measured temperatures. However, in some cases a change in the intensity ratio at the spray impingement area, in the form of a permanent “stain”, could be observed after multiple injections. The formation of this stain was less likely with increasing annealing time of the coating as well as lower plate operating temperatures during the injection experiments. Finally, the experimental results indicate a noticeable influence of the thickness of the phosphor coating on the measured spray-induced wall cooling history. Hence, for quantitative analysis, a compromise between coating thickness and measurement accuracy needs to be considered for similar applications where the heat transfer rates are very high

    Challenges and opportunities of water quality monitoring and multi-stakeholder management in small islands: the case of Santa Cruz, Galápagos (Ecuador)

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    Sustainable water resources management roots in monitoring data reliability and a full engagement of all institutions involved in the water sector. When competences and interests are overlapping, however, coordination may be difficult, thus hampering cooperative actions. This is the case of Santa Cruz Island (Galápagos, Ecuador). A comprehensive assessment on water quality data (physico-chemical parameters, major elements, trace elements and coliforms) collected since 1985 revealed the need of optimizing monitoring efforts to fill knowledge gaps and to better target decision-making processes. A Water Committee (Comité de la gestión del Agua) was established to foster the coordinated action among stakeholders and to pave the way for joint monitoring in the island that can optimize the efforts for water quality assessment and protection. Shared procedures for data collection, sample analysis, evaluation and data assessment by an open-access geodatabase were proposed and implemented for the first time as a prototype in order to improve accountability and outreach towards civil society and water users. The overall results reveal the high potential of a well-structured and effective joint monitoring approach within a complex, multi-stakeholder framework.publishedVersio

    Factors Influencing Cotton Farmers’ Perceptions about the Importance of Information Sources in Precision Farming Decisions

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    Information generated by precision farming technologies is of particular importance to producers. Precision farming technologies implies the ability to improve the management of production factors using site-specific information. This study examines factors influencing cotton farmers’ perceptions about the importance of crop consultants, farm input dealerships, Extension, other farmers, trade shows, the Internet and printed news/media for making precision farming decisions using a rank ordered logit model (ROLM). Results suggest that age, land tenure, income, percentage of income from farming, and location may affect farmers’ perceptions about the importance of different information sources when making decisions about precision farming technologies. Results suggest that regardless of farmer/farm business characteristics other farmers (OF) is one of the most important information sources when making precision farming decisions. Findings suggest that high income producers are more likely to prefer crop consultants, University/Extension, trade shows, and the Internet over OF as a source of information when making decisions about precision farming technologies. Findings also suggest that researchers need to be very careful when designing questions that ask respondents to rank alternatives so that they guarantee that individuals with different skills are able to precisely understand what is being asked. Decreasing the number of alternatives respondents must consider may be one strategy to reduce the complexity of ranking questions to minimize the probability of the respondents leaving alternatives unranked or ranking them randomly.Information-source preferences, Rank Ordered Logit Model, Precision Farming, Production Economics, Research Methods/ Statistical Methods, Q16, C25,

    The influence of social support on the wellbeing of immigrants residing in Italy: Sources and functions as predictive factors for life satisfaction levels, sense of community and resilience

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    Moving from one country to another involves not only separation from the country of origin, but also the tiring process of integration into a new physical, institutional, and sociocultural context, which may expose migrants to acculturation stress. The loss of former support networks, or at the very least their transformation, presents immigrants with the need to rebuild their social support systems in the host country, involving an active search for support. Therefore, the aim of study is to analyze the structure of informal social support and its capacity to predict immigrants’ sense of community, resilience, and satisfaction with life. The results confirm that social support predicts satisfaction with life, sense of community, and resilience. Our findings highlight the way sources and frequency of support, and the satisfaction with which they are associated, have different degrees of predictive value on the dependent variables under investigation. In this study, it can be concluded that social support is an important factor in the well-being of migrants and their integration into the host community. The results have an important practical value in promoting interventions that improve immigrants’ support networks and, consequently, increase their satisfaction with life, sense of community, and resilience.Funding for open access charge: Universidad de Málaga / CBU
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