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One of the problems facing public education institutions in Brazil is the question of the correct handling and treatment of waste electrical and electronic equipment (WEEE). Being that these institutions are part of the public sector, they should adhere to Decree no. 99,658/1990 for the disposal of their goods. However, this decree is not completely in accordance with the Brazilian National Solid Waste Policy (PNRS), especially when considering the regulations for disposal of public goods. Thus, these institutions have no WEEE management model which encompasses not only the Decree but also the PNRS. An example of this situation can be found at the Federal University of Itajubá (UNIFEI) in Minas Gerais, Brazil. Due to the lack of such a management model, the university warehouse is at full capacity and unable to receive additional electronic equipment. Therefore, the objective of this study is to create a management model for WEEE to be used at public education institutions using the guidelines set forth in both the Decree and the PNRS. An action research investigation was performed at UNIFEI which relied upon two improvement and learning cycles to deal with all the WEEE found at the university. The first was undertaken at the university warehouse and the second at other sectors within the institution. In addition to the practical results obtained by properly disposing of 474 WEEE products, this study showed that action research is an adequate management tool for public institutions looking to deal with problems of this nature, being that these institutions are almost always subject to bureaucratic controls with respect to their public property, and expected to follow rigorous legislation that is often times controversial.  相似文献   
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The variance of a portfolio can be forecast using a single index model or the covariance matrix of the portfolio. Using univariate and multivariate conditional volatility models, this paper evaluates the performance of the single index and portfolio models in forecasting value‐at‐risk (VaR) thresholds of a portfolio. Likelihood ratio tests of unconditional coverage, independence and conditional coverage of the VaR forecasts suggest that the single‐index model leads to excessive and often serially dependent violations, while the portfolio model leads to too few violations. The single‐index model also leads to lower daily Basel Accord capital charges. The univariate models which display correct conditional coverage lead to higher capital charges than models which lead to too many violations. Overall, the Basel Accord penalties appear to be too lenient and favour models which have too many violations. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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Austenite formation kinetics in two high-strength experimental microalloyed steels with different initial microstructures compris-ing bainite–martensite and ferrite–martensite/austenite microconstituents was studied during continuous heating by dilatometric analysis. Austenite formation occurred in two steps:(1) carbide dissolution and precipitation and (2) transformation of residual ferrite to austenite. Di-latometric analysis was used to determine the critical temperatures of austenite formation and continuous heating transformation diagrams for heating rates ranging from 0.03°C×s?1 to 0.67°C×s?1. The austenite volume fraction was fitted using the Johnson–Mehl–Avrami–Kolmogorov equation to determine the kinetic parameters k and n as functions of the heating rate. Both n and k parameters increased with increasing heat-ing rate, which suggests an increase in the nucleation and growth rates of austenite. The activation energy of austenite formation was deter-mined by the Kissinger method. Two activation energies were associated with each of the two austenite formation steps. In the first step, the austenite growth rate was controlled by carbon diffusion from carbide dissolution and precipitation;in the second step, it was controlled by the dissolution of residual ferrite to austenite.  相似文献   
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Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by activation of the type I interferon (IFN) pathway. Here we convincingly replicate association of the IFN regulatory factor 5 (IRF5) rs2004640 T allele with SLE in four independent case-control cohorts (P = 4.4 x 10(-16)) and by family-based transmission disequilibrium test analysis (P = 0.0006). The rs2004640 T allele creates a 5' donor splice site in an alternate exon 1 of IRF5, allowing expression of several unique IRF5 isoforms. We also identify an independent cis-acting variant associated with elevated expression of IRF5 and linked to the exon 1B splice site. Haplotypes carrying the variant associated with elevated expression and lacking the exon 1B donor site do not confer risk of SLE. Thus, a common IRF5 haplotype driving elevated expression of multiple unique isoforms of IRF5 is an important genetic risk factor for SLE, establishing a causal role for type I IFN pathway genes in human autoimmunity.  相似文献   
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We report a recurrent microdeletion syndrome causing mental retardation, epilepsy and variable facial and digital dysmorphisms. We describe nine affected individuals, including six probands: two with de novo deletions, two who inherited the deletion from an affected parent and two with unknown inheritance. The proximal breakpoint of the largest deletion is contiguous with breakpoint 3 (BP3) of the Prader-Willi and Angelman syndrome region, extending 3.95 Mb distally to BP5. A smaller 1.5-Mb deletion has a proximal breakpoint within the larger deletion (BP4) and shares the same distal BP5. This recurrent 1.5-Mb deletion contains six genes, including a candidate gene for epilepsy (CHRNA7) that is probably responsible for the observed seizure phenotype. The BP4-BP5 region undergoes frequent inversion, suggesting a possible link between this inversion polymorphism and recurrent deletion. The frequency of these microdeletions in mental retardation cases is approximately 0.3% (6/2,082 tested), a prevalence comparable to that of Williams, Angelman and Prader-Willi syndromes.  相似文献   
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In this article, we publish the critical edition of Andalò di Negro’s De compositione astrolabii, with English translation and commentary. The mathematician and astronomer Andalò di Negro (Genoa ca. 1260–Naples 1334) presumably redacted this treatise on the astrolabe in the 1330s, while residing at the court of King Robert of Naples. The present edition has three purposes: first, to make available a text missing from the previous compilations of works by Andalò di Negro (ed. Bonus Opus preclarissimum astrolabij compositum a domino Andalo de nigro genuensi foeliciter incipit…Explicit tractatus astrolabij excellentissimi mathematici Andalonis genuensis, emendatus per celeberrimum et doctissimum astronomum magistrum Petrum Bonum Avogarium in foelici gymnasio ferrariensi. [Ferrara]: magister Johannes Picardus, 1475; Bertolotto II Trattato sull’Astrolabio di Andalò di Negro, riprodotto dall’edizione ferrarese del 1475, con prefazione del socio G. Bertolotto. Atti della società ligure di storia patria 25, 51–141, 1892; Fornaciari and Faracovi Trattato sull’astrolabio di Andalò di Negro, a cura di P.E. Fornaciari e O.P. Faracovi. Pubblicazione del Comune di Livorno in occasione della “Primavera della Scienza a Livorno” (febbraio-maggio 2005). Ospedaletto: Pacini editore, 2005); second, to revise a privately circulated edition of the text (Cesari L’astrolabio di Andalò di Negro, Parte I, edizione critica. Milano: s.n., 1984a; Practica Astrolabii di Andalò di Negro, Parte I. Edizione critica. Bergamo: Istituto Universitario di Bergamo, 1984b); and third, to help disseminating one of the rare Latin texts presenting the principles of the stereographic projection which underlie the construction of the astrolabe.

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The objective of this paper is to study and report upon the elaboration of a selective waste collection program in a Brazilian city through action research; the overarching goal is that all knowledge generated may serve as a basis of information and reference to aid in decision making for similar programs globally. The municipality chosen was São Lourenço in the state of Minas Gerais. The implementation of the selective waste collection program happened over the course of multiple improvement and learning cycles, and enabled many environmental, economic and social benefits for all of the project’s stakeholders. Eighty-nine tons of potentially recycled material were sent to recycling processes rather than being disposed of in a landfill. No great difficulties were observed for the use of action research as a method, but some challenges were encountered and overcome during the whole process, due to the lack of structure and confidence on part of the population, in relation to the selective collection program. The choice for action research as the methodology and the use of improvement and learning cycles proved to increase the project’s overall efficiency, making it possible to make decisions more quickly, generating better results, and enabling replications of good decisions and correction of errors from one cycle to the next.  相似文献   
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人类行为存在多种形式,其中灾害情况下的逃生行为研究得较多,如由恐慌引起的人群逃逸。本文关注在正常环境下有限空间内的人类行为,如公车、教室等,目的是研究其行为模式。研究基于经济学和心理学出发,将人类行为看作自利人之间的交互作用的结果,自利人根据现实的或潜在的收益做出决定,同时引入心理距离和惰性概念,提出了一个基于心理距离和惰性的个体行为模型,并通过模拟实验研究心理距离和惰性如何影响个体行为。实验结果较真实地涌现出现实世界中的宏观群体行为模式,说明本模型能够对有限空间内的人类行为做出较合理的解释。  相似文献   
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