| 1 | 手卫生在遏制抗微生物药物耐药性中的作用显示文摘近年来,抗微生物药物耐药性(antimicrobial resistance,AMR)在全球范围内飞速增长[1].据欧洲疾病预防与控制中心估计,欧洲范围内AMR相关感染每年将导致2.5万例患者死亡,额外增加250万住院日以及15亿欧元花费[2].美国的情况同样严重,据美国疾病控制与预防中心(CDC)估计,美国每年仅耐碳青霉烯类肠杆菌科细菌引起的感染就会导致610例患者死亡[3].因此,预防和控制AMR的传播已迫在眉睫. | 乔甫 Daniela Pires Didier Pittet | 2017 | 中国感染控制杂志2017，16，4： | 3 |
| 4 | The Igarapé Weir decelerated transport of contaminated sediment in the Paraopeba River after the failure of the B1 tailings dam(Brumadinho)显示文摘The B1 dam of Corrego do Feijao Mine,owned by Vale,S.A.mining company and located on the Ferro-Carvao stream,collapsed and injected 2.8 Mm^(3)of clayey,silty,and sandy iron-and manganese-rich tailings into the Paraopeba River(Minas Gerais state,Brazil).The accident occurred on 25 January 2019 and the tailings have been co-transported with coarser natural sediment since then,being partly trapped in the Igarape Weir reservoir located on the Paraopeba River nearly 45 km downstream the injection point.The general purpose of the current study was to model suspended sediment transport in the vicinity of the Igarape Weir aiming to assess the concomitant barrier effect imposed by this structure.Specifically,the spatial distributions of suspended clay,silt,and very fine-grained sand fractions(CSS)of sediment were mapped around the Igarape Weir under low-flow(16 m^(3)/s)and high-flow(5 to 10,000 years return period stream discharge;699e2,699 m^(3)/s)regimes,using RiverFlow2D as the modelling tool.The concentrations of the various grain materials in the upstream and downstream sectors were quantified linking the barrier effect to concentration reductions in the direction of stream flow.It was also a study goal to calculate differences of iron and manganese concentrations in the sediment+tailings mixtures along the Paraopeba River.The study results showed reductions in the CSS between 6.6%and 18%,from upstream to downstream of the Igarape Weir,related with backwater effects,free and sub-merged hydraulic jumps,bank sedimentation in periods of high flow,and streambed sedimentation controlled by channel sinuosity and tailings density.These reductions were accompanied by drops in the concentrations of iron and manganese present in the clay and silt fractions,which varied between 6%and 42%under low flows and between 16%and 44%under high flows.Bank sedimentation was viewed as a potential threat to the riparian vegetation in the long-term.Dredging is the potentially most effective mitigation measure to help lead the Paraopeba River to a pre-rupture condition.The retention of sediment+tailings transported in suspension is less effective than the trapping of bedload sediment+tailings behind the Igarape weir.The efficacy of sediment trapping is expected to be larger for natural sediment because it is much coarser than the tailings.In that context,the simulations revealed for the low-flow period that 33.6%of the sediment deposition comprised suspended transport of natural sediment(thus,was comprised 66.4%of bedload transport),this proportion rose to 86.9%for mixtures of natural sediment+tailings,a result that did not differ much for the high-flow periods. | Daniela Patrícia Salgado Terencio Fernando Antonio Leal Pacheco Renato Farias do Valle Junior Mayte Maria Abreu Pires de Melo Silva Teresa Cristina Tarle Pissarra Marília Carvalho de Melo Carlos Alberto Valera Luís Filipe Sanches Fernandes | 2023 | International Journal of Sediment Research2023，38，5： | 0 |
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