86 resultados para Zach Fratto


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Three initiatives with respect to water reporting in the mining sector are compared in this paper to understand the quantities that are asked for by each initiative and the guidelines of those initiatives through means of a case study. The Global Reporting Initiative (GRI) was chosen because it has achieved widespread acceptance amongst mining companies and its water-related indicators are widely reported in corporate sustainability reporting. In contrast, the Water Footprint Network, which has been an important initiative in food and agricultural industries, has had low acceptance in the mining industry. The third initiative is the Water Accounting Framework, a collaboration between The Minerals Council of Australia and the Sustainable Minerals Institute of the University of Queensland. A water account had previously been created according to the Water Accounting Framework for the case study site, an open pit coal mine in the Bowen Basin. The resulting account provided consistent data for the Global Reporting Initiative (GRI) and the Water Footprint attributable to mining but in particular, a deficiency in the GRI indicator of EN10 reuse and recycling efficiency was illustrated quantitatively. This has far-reaching significance due to the widespread use of GRI indicators in mining corporate reports.

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In this paper, using the intrinsically disordered oncoprotein Myc as an example, we present a mathematical model to help explain how protein oscillatory dynamics can influence state switching. Earlier studies have demonstrated that, while Myc overexpression can facilitate state switching and transform a normal cell into a cancer phenotype, its downregulation can reverse state-switching. A fundamental aspect of the model is that a Myc threshold determines cell fate in cells expressing p53. We demonstrate that a non-cooperative positive feedback loop coupled with Myc sequestration at multiple binding sites can generate bistable Myc levels. Normal quiescent cells with Myc levels below the threshold can respond to mitogenic signals to activate the cyclin/cdk oscillator for limited cell divisions but the p53/Mdm2 oscillator remains nonfunctional. In response to stress, the p53/Mdm2 oscillator is activated in pulses that are critical to DNA repair. But if stress causes Myc levels to cross the threshold, Myc inactivates the p53/Mdm2 oscillator, abrogates p53 pulses, and pushes the cyclin/cdk oscillator into overdrive sustaining unchecked proliferation seen in cancer. However, if Myc is downregulated, the cyclin/cdk oscillator is inactivated and the p53/Mdm2 oscillator is reset and the cancer phenotype is reversed. (C) 2015 Elsevier Ltd. All rights reserved.

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在糖化学合成中,1,6-脱水吡喃糖不仅是合成具有生物活性低聚糖、糖共体、抗原、抗体以及天然产物等化合物重要原料,而且还是许多具有生物活性的天然产物的结构单元。同时,它还具有[3,2,1]的双环缩醛结构,使其在糖化学合成中具有高的立体选择性和区域选择性,同时减少了C-1 和C-6 位的保护和去保护的优点。此外,环内的缩醛开环后,又可以相应地在C-1 和C-6 位进行官能团转化以及糖苷化反应。 本文报道了一种新的1,6-脱水吡喃糖的合成方法,并设计合成了2-C-支链-1,6-脱水吡喃葡萄糖1-195、1-197、1-198 以及2-C-支链-6-硫代1,6-脱水吡喃葡萄糖1-225。到目前为止,1,6-脱水糖开环并进行糖苷化反应,存在选择性较差、产率低的缺点。我们发现,在乙腈做溶剂的条件下,NiCl5 能高立体选择性高产率地催化化合物1-195、1-197、1-198 开环并与ROH、RSH 发生糖苷化反应。在NiCl5-乙腈条件下,合成了一系列2-C-支链-α-糖苷和2-C-支链-β-硫代糖苷,并对2-C-支链1,6-脱水吡喃葡萄糖的生成机理以及开环机理进行了探讨。 烯糖在糖化学合成中是重要的起始原料,从Fischer 首次合成烯糖至今,一直不断地有新的合成方法出现。但目前文献报道的方法存在所用试剂有毒、价格贵和操作繁琐等缺点。我们对Fischer-Zach 方法进行了改进, 发现Zn-NaH2PO4-H2O 和Zn-PEG600-H2O 体系都能很好地合成烯糖。该方法具有条件温和、绿色环保、操作简单的优点。在Zn-NaH2PO4 溶液或Zn-PEG600 条件下,以溴代糖为原料,高产率地合成一系列的烯糖。 The 1,6-anhydrohexopyranoses are crucial subunits of myriad bioactive nature products, as well as important syntons of carbohydrate chemistry which have been extensively used to prepare the biologically potential oligosaccharides, glycoconjugates, antibiotics, and structurally varied nature products. Their particular [3.2.1] bicyclic skeleton makes them have high regio- and stereo-control in a variety of reactions, and such structure avoids protecting hydroxyl groups at C1 and C6.Additionally, the cleavage of the internal acetal under acidic conditions could be beneficial for further transformations of functional group and glycosylation of the corresponding pyranosyl sugar at the C6 or C1 site. Herein we developed a novel approach to prepare the 1,6-anhydrohexopyranose, and synthesized the 2-C-branched-1,6-anhydrohexopyranose 1-195, 1-197, 1-198 and 2-C-branched-6-thio-1,6-anhydrohexopyranose 1-225. Until now, glycosylation of 1,6-anhydrohexopyranoses has been limited because of the low yields and low stereoselectivity. In this paper, we found that NiCl5-MeCN system could selectively cleave the ring of 1,6-anhydrohexopyranoses with alcohols and thiols at room temperature in high yields. A series of 2-C-branched-α-glycosides and 2-C-branched-β-thioglycosides have been synthesized via NiCl5-catalyzed. Furthermore, we investigated the formation and ring-opening mechanism of 2-C-acetylmethyl-1,6-anhydrohexopyranose. Glycals are significant starting material in carbohydrate chemistry. After the Fischer-Zach method for forming glucal was reported for the first time, the numerous synthetic methods for glycals have been explored. However, there are several drawbacks in the existing methods, such as the usage of very expensive and toxic reagents, intricate operation, and the influence of acid-sensitive and base-sensitive functional group. We improved the Fischer-Zach method and developed a facile, mild and environmentally benign methodology towards the synthesis of the glycals in Zn-NaH2PO4-H2O or Zn-PEG600-H2O system. Our method involves the treatment of glycosyl bromides with Zn in NaH2PO4 aqueous solution or PEG600-H2O at room temperature, affording various glycals in excellent yields.

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Gemstone Team Peace in Prisons

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Objective-Inflammation and proteolysis crucially contribute to myocardial ischemia and reperfusion injury. The extracellular matrix metalloproteinase inducer EMMPRIN (CD147) and its ligand cyclophilin A (CyPA) may be involved in both processes. The aim of the study was to characterize the role of the CD147 and CyPA interplay in myocardial ischemia/reperfusion (I/R) injury.Methods and Results-Immunohistochemistry showed enhanced expression of CD147 and CyPA in myocardial sections from human autopsies of patients who had died from acute myocardial infarction and from mice at 24 hours after I/R. At 24 hours and 7 days after I/R, the infarct size was reduced in CD147(+/-) mice vs CD147(+/+) mice (C57Bl/6), in mice (C57Bl/6) treated with monoclonal antibody anti-CD147 vs control monoclonal antibody, and in CyPA(-/-) mice vs CyPA(+/+) mice (129S6/SvEv), all of which are associated with reduced monocyte and neutrophil recruitment at 24 hours and with a preserved systolic function at 7 days. The combination of CyPA(-/-) mice with anti-CD147 treatment did not yield further protection compared with either inhibition strategy alone. In vitro, treatment with CyPA induced monocyte chemotaxis in a CD147-and phosphatidylinositol 3-kinase-dependent manner and induced monocyte rolling and adhesion to endothelium (human umbilical vein endothelial cells) under flow in a CD147-dependent manner.Conclusion-CD147 and its ligand CyPA are inflammatory mediators after myocardial ischemia and reperfusion and represent potential targets to prevent myocardial I/R injury.

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En un país que ha afrontado un conflicto armado interno por décadas en el cual la posición geográfica es de difícil acceso y los puntos de control son remotos, se hace necesario generar un sistema de distribución y almacenamiento óptimo y eficaz. Un sistema donde los tiempos de respuesta sean inmediatos, las cantidades requeridas sean exactamente iguales a las enviadas y la calidad óptima para que los oficiales, sub oficiales e infantes de marina pueda cumplir con su función. En el periodo presidencial de Álvaro Uribe Vélez (2002-2010), se crearon los comandos conjuntos lo que llevó a las fuerzas armadas a estar incorporando año tras año nuevo personal efectivo y esto a su vez implicó un mayor abastecimiento de armamento, bases, intendencia y alimentos.. Este estudio está centrado en el abastecimiento de intendencia de la Armada Nacional donde se analiza la bodega de almacenamiento, el proceso de distribución y la optimización de recursos físicos de la Dirección de Abastecimiento de la Armada Nacional. Adicionalmente, se analiza la optimización del espacio de la bodega de almacenaje para incrementar la rotación de inventarios, el control de dotación y la distribución dentro de la bodega. Finalmente se plantea un plan de mejora en la cadena de suministro utilizando herramientas como Flujo-grama causa-efecto, Lay-out y diagrama de recorrido.

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Bemisia tabaci biótipo B é um dos principais insetos-praga na cultura da abobrinha (Cucurbita pepo L.). O manejo dessa mosca-branca tornou-se grande desafio aos agricultores, uma vez que esta apresenta rápida capacidade de desenvolver resistência a diferentes classes de inseticidas. Como alternativa vem sendo investigado o uso de extratos vegetais com atividades inseticida e/ou insetistática, os quais têm revelado resultados promissores no combate a inseto. O presente trabalho teve por objetivo avaliar os possíveis efeitos de sete extratos provenientes de cinco espécies vegetais, Ruta graveolens L. (folhas), Azadirachta indica A. Juss. (folhas + ramos), Trichilia pallida Swartz (ramos), T. pallida (folhas), A. indica (amêndoas), Chenopodium ambrosioides L. (inflorescências + ramos+ folhas) e Mentha pulegium L. (folhas), sobre Bemisia tabaci biótipo B em abobrinha, por meio de testes de repelência e deterrência para oviposição. em teste com chance de escolha, avaliou-se a atratividade e determinou-se o índice de repelência após 6, 24 e 48 horas da aplicação dos extratos. A oviposição foi verificada após a terceira contagem do número de adultos. O extrato à base de folhas de M. pulegium mostrou repelência e deterrência à oviposição de B. tabaci biótipo B, podendo ser recomendado como alternativa para o manejo do inseto.

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The control of defoliating caterpillars in eucalyptus forests via the application of chemical and biological insecticides is a complex issue, mainly due to the large size of plantations and the height of trees. Because of this complexity, alternate control methods have been proposed, such as biological control. Several factors should be taken into consideration for biological control programs to be successful, including density of natural enemies released. In this experiment we used 48-hour-old Thyrinteina arnobia pupae exposed to parasitism by 48-hour-old Trichospilus diatraeae females at the following parasitoid/host ratios, respectively: 1:1, 7:1, 14:1, 21:1, 28:1, and 35:1, with 15 replicates per treatment. Density was an important factor for T. diatraeae development, since parasitism rates of 33.3% were found at a density of 1 female per pupa, while no significant differences were found among parasitism rates for densities of 7, 14, 21, 28, and 35 females/pupa, with parasitism rates above 70 %. As to emergence, densities of 1:1 and 35:1 did not differ statistically, with low emergence rates. The 7:1 density had an intermediate performance, while densities of 14:1, 21:1, and 28:1 were the most effective, with emergence rates above 90%. With regard to the number of emerged parasitoids there was a positive intraspecific interference up to the 28:1 density. There was an increase in development period from egg-adult as the density of females per pupa increased.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Spodoptera cosmioides (Lepidoptera: Noctuidae)é uma espécie polífaga e alimenta-se de grande número de plantas cultivadas e espontâneas. No Brasil, as culturas do abacaxi, algodoeiro, arroz, berinjela, cebola, eucalipto, pimentão e tomateiro, entre outras hortaliças, são consideradas hospedeiras da praga. Entretanto, apesar da ampla gama de hospedeiros, sua ocorrência como praga é relatada relacionada a desequilíbrios provocados pelo uso excessivo de inseticidas de amplo espectro, o que vem causando a resistência da praga a inseticidas. Devido a essa complexidade, métodos alternativos de controle têm sido propostos, por exemplo, o controle biológico através da utilização de parasitóides. Trichospilus diatraeae (Hymenptera: Eulophidae) é um parasitóide gregário pupal preferencialmente de espécies da ordem Lepidoptera. Este é o primeiro relato de T. diatraeae parasitando pupas de S. cosmioides, parasitóide que oferece novas perspectivas para os programas de controle biológico.