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911.
Annie‐Claude Parent François Anctil Véronique Cantin Marie‐Amélie Boucher 《Journal of the American Water Resources Association》2008,44(3):679-688
Abstract: Snowmelt largely affects runoff in watersheds in Nordic countries. Neural networks (NN) are particularly attractive for streamflow forecasting whereas they rely at least on daily streamflow and precipitation observations. The selection of pertinent model inputs is a major concern in NNs implementation. This study investigates performance of auxiliary NN inputs that allow short‐term streamflow forecasting without resorting to a deterministic snowmelt routine. A case study is presented for the Rivière des Anglais watershed (700 km2) located in Southern Québec, Canada. Streamflow (Q), precipitations (rain R and snow S, or total P), temperature (T) and snow lying (A) observations, combined with climatic and snowmelt proxy data, including snowmelt flow (QSM) obtained from a deterministic model, were tested. NN implemented with antecedent Q and R produced the largest gains in performance. Introducing increments of A and T to the NNs further improved the performance. Long‐term averages, seasonal data, and QSM failed to improve the networks. 相似文献
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Francesca Romana Grati Denise Molina Gomes Jose Carlos Pinto B. Ferreira Celine Dupont Viola Alesi Laetitia Gouas Nina Horelli-Kuitunen Kwong Wai Choy Sandra García-Herrero Alberto Gonzalez de la Vega Krzysztof Piotrowski Rita Genesio Gloria Queipo Barbara Malvestiti Bérénice Hervé Brigitte Benzacken Antonio Novelli Philippe Vago Kirsi Piippo Tak Yeung Leung Federico Maggi Thibault Quibel Anne Claude Tabet Giuseppe Simoni François Vialard 《黑龙江环境通报》2015,35(8):801-809
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Steven M. Lipson Fatma S. Ozen Laina Karthikeyan Ronald E. Gordon 《Food and environmental virology》2012,4(4):168-178
Cranberry (Vaccinium macrocarpon) and grape (Vitis labrusca) juices, and these species?? secondary plant metabolites [i.e., proanthocyanidins (PACs)] possess antiviral activity. An understanding of the mechanism(s) responsible for these juices and their polyphenolic constituents?? direct effect on enteric virus integrity, however, remains poorly defined. Using the rotavirus (RTV) as a model enteric virus system, the direct effect of manufacturer-supplied and commercially purchased juices [Ocean Spray Pure Cranberry 100?% Unsweetened Juice (CJ), Welch??s 100?% Grape Juice (GJ), 100?% Concord (PG) and 100?% Niagara juices (NG)] and these species?? cranberry (C-PACs) and grape PACs (G-PACs) was investigated. Loss of viral capsid integrity in cell-free suspension by juices and their PACs, and as a factor of pH, was identified by an antigen (RTV) capture enzyme-linked immunosorbent assay. At native and an artificially increased suspension at or near pH 7, loss of viral infectivity occurred after 5?min, in the order CJ?>?NG?=?GJ?>?PG, and PG?>?GJ?=?NG?=?CJ, respectively. Antiviral activity of CJ was inversely related to pH. Grape, but not cranberry PACs, displayed a comparatively greater anti-RTV activity at a suspension pH of 6.7. Anti-RTV activity of C-PACs was regained upon reduction of RTV-cranberry PAC suspensions to pH 4. An alteration or modification of Type A PAC (of V. macrocarpon) structural integrity at or near physiologic pH is suggested to have impacted on this molecule??s antivirus activity. Type B PACs (of V. labrusca) were refractive to alternations of pH. Significantly, findings from pure system RTV?CPAC testing paralleled and in turn, supported those RTV-juice antiviral studies. Electron microscopy showed an enshroudment by PACs of RTV particles, suggesting a blockage of viral antigenic binding determinants. The implications of our work are significant, especially in the interpretation of PAC (and PAC-containing food)?CRTV interactions in the differing [pH] conditions of the gastrointestinal tract. 相似文献
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Rodolfo Salm Lisa Feder Mario Augusto Gonçalves Jardim Nefertiti Hass Euphly Jalles-Filho Ana Maria Costa 《Environment, Development and Sustainability》2009,11(1):161-173
In a meeting between FUNAI (the Brazilian Indian National Foundation) and the Kayapo in the Kayapo village of Aukre, in October
2005, the Kayapo Indians requested support to increase the culture of coconuts (Cocos nucifera) in their lands. The introduction of exotic species is a cause of biological diversity loss throughout the world. However,
this is by no means applicable to all kinds of exotic species. We argue that the culture of coconuts may actually be a useful
tool for the conservation of this country’s indigenous lands, despite criticism to the contrary. It may also be useful as
source for raw material for the indigenous people who are presently experiencing a population boom. For the Kayapo of south-eastern
Amazonia, such a demographic explosion, coupled with their increasing dependence on money to purchase industrialized goods,
tend to substantially increase the pressure on their lands, which still contain a substantial amount of well-preserved seasonally-dry
Amazonian forests. We investigated the actual economic relevance of coconuts for the Kayapo by measuring human and coconut
populations and found that this exotic palm is not important for the subsistence of these Indians, due to coconut scarcity,
and that such importance is not forthcoming. In the Amazon, coconuts may be particularly useful for the Indians’ nutrition
due to the high energetic value of the solid endosperm of the mature fruit. Therefore, given the importance of indigenous
lands for the conservation of the Amazonian forests, the encouragement of subsistence coconut cultures in indigenous lands
is defensible as a measure for the conservation of biodiversity. 相似文献