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651.
The goal of this article is to evaluate the impact of the drastic Spanish Penal Code reform on the number of road deaths in Spain and the time that the effects might last. This is achieved by means of multivariate unobserved component models set up in a state space framework estimated using maximum likelihood. In short, with this reform Spain might be considered to be closing the final gap that kept it apart from other developed countries as far as the road accident rate is concerned. We have found two different types of effects on Spanish road traffic fatalities. Initially, a month before the reform was passed there was a 24.7 percent fall in Spanish road deaths. After the Bill had been passed and for the following thirteen months, the reduction stayed at a constant sixteen percent. This reform has reduced Spanish road fatalities by 534 in all between November 2007 and December 2008 and the effects will foreseeably continue during 2009. 相似文献
652.
Seed dispersal is a crucial component of plant population dynamics. Human landscape modifications, such as habitat destruction and fragmentation, can alter the abundance of fruiting plants and animal dispersers, foraging rates, vector movement, and the composition of the disperser community, all of which can singly or in concert affect seed dispersal. Here, we quantify and tease apart the effects of landscape configuration, namely, fragmentation of primary forest and the composition of the surrounding forest matrix, on individual components of seed dispersal of Heliconia acuminata, an Amazonian understory herb. First we identified the effects of landscape configuration on the abundance of fruiting plants and six bird disperser species. Although highly variable in space and time, densities of fruiting plants were similar in continuous forest and fragments. However, the two largest-bodied avian dispersers were less common or absent in small fragments. Second, we determined whether fragmentation affected foraging rates. Fruit removal rates were similar and very high across the landscape, suggesting that Heliconia fruits are a key resource for small frugivores in this landscape. Third, we used radiotelemetry and statistical models to quantify how landscape configuration influences vector movement patterns. Bird dispersers flew farther and faster, and perched longer in primary relative to secondary forests. One species also altered its movement direction in response to habitat boundaries between primary and secondary forests. Finally, we parameterized a simulation model linking data on fruit density and disperser abundance and behavior with empirical estimates of seed retention times to generate seed dispersal patterns in two hypothetical landscapes. Despite clear changes in bird movement in response to landscape configuration, our simulations demonstrate that these differences had negligible effects on dispersal distances. However, small fragments had reduced densities of Turdus albicollis, the largest-bodied disperser and the only one to both regurgitate and defecate seeds. This change in Turdus abundance acted together with lower numbers of fruiting plants in small fragments to decrease the probability of long-distance dispersal events from small patches. These findings emphasize the importance of foraging style for seed dispersal and highlight the primacy of habitat size relative to spatial configuration in preserving biotic interactions. 相似文献
653.
Boyero L Pearson RG Dudgeon D Graça MA Gessner MO Albariño RJ Ferreira V Yule CM Boulton AJ Arunachalam M Callisto M Chauvet E Ramírez A Chará J Moretti MS Gonçalves JF Helson JE Chará-Serna AM Encalada AC Davies JN Lamothe S Cornejo A Li AO Buria LM Villanueva VD Zúñiga MC Pringle CM 《Ecology》2011,92(9):1839-1848
Most hypotheses explaining the general gradient of higher diversity toward the equator are implicit or explicit about greater species packing in the tropics. However, global patterns of diversity within guilds, including trophic guilds (i.e., groups of organisms that use similar food resources), are poorly known. We explored global diversity patterns of a key trophic guild in stream ecosystems, the detritivore shredders. This was motivated by the fundamental ecological role of shredders as decomposers of leaf litter and by some records pointing to low shredder diversity and abundance in the tropics, which contrasts with diversity patterns of most major taxa for which broad-scale latitudinal patterns haven been examined. Given this evidence, we hypothesized that shredders are more abundant and diverse in temperate than in tropical streams, and that this pattern is related to the higher temperatures and lower availability of high-quality leaf litter in the tropics. Our comprehensive global survey (129 stream sites from 14 regions on six continents) corroborated the expected latitudinal pattern and showed that shredder distribution (abundance, diversity and assemblage composition) was explained by a combination of factors, including water temperature (some taxa were restricted to cool waters) and biogeography (some taxa were more diverse in particular biogeographic realms). In contrast to our hypothesis, shredder diversity was unrelated to leaf toughness, but it was inversely related to litter diversity. Our findings markedly contrast with global trends of diversity for most taxa, and with the general rule of higher consumer diversity at higher levels of resource diversity. Moreover, they highlight the emerging role of temperature in understanding global patterns of diversity, which is of great relevance in the face of projected global warming. 相似文献
654.
Verónica Bastos José M.P. Ferreira-de-Oliveir Joana Carrol Ana L. Daniel-da-Silv Iola F. Duarte Conceição Santos Helena Oliveira 《环境科学学报(英文版)》2017,29(1):191-201
The antibacterial potential of silver nanoparticles(AgNPs) resulted in their increasing incorporation into consumer,industrial and biomedical products.Therefore,human and environmental exposure to AgNPs(either as an engineered product or a contaminant)supports the emergent research on the features conferring them different toxicity profiles.In this study,30 ran AgNPs coated with citrate or poly(ethylene glycol)(PEG) were used to assess the influence of coating on the effects produced on a human hepatoma cell line(HepG2),namely in terms of viability,apoptosis,apoptotic related genes,cell cycle and cyclins gene expression.Both types of coated AgNPs decreased cell proliferation and viability with a similar toxicity profile.At the concentrations used(11 and 5 μg/mL corresponding to IC50 and-IC10 levels,respectively) the amount of cells undergoing apoptosis was not significant and the apoptotic related genes BCL2(anti-apoptotic gene)and BAX(pro-apoptotic gene) were both downregulated.Moreover,both AgNPs affected HepG2 cell cycle progression at the higher concentration(11 μg/mL) by increasing the percentage of cells in S(synthesis phase) and G2(Gap 2 phase) phases.Considering the cell-cycle related genes,the expression of cyclin B1 and cyclin E1 genes were decreased.Thus,this work has shown that citrate- and PEG-coated AgNPs impact on HepG2 apoptotic gene expression,cell cycle dynamics and cyclin regulation in a similar way.More research is needed to determine the properties that confer AgNPs at lower toxicity,since their use has proved helpful in several industrial and biomedical contexts. 相似文献
655.
Martins Thiago Rodrigues Bertuol Daniel Assumpo Tanabe Eduardo Hiromitsu 《Journal of Material Cycles and Waste Management》2022,24(2):633-641
Journal of Material Cycles and Waste Management - Technological development has led to a growing generation of waste electrical and electronic equipment, including cables. This work concerns the... 相似文献
656.
Ganie Showkat Ali Ali Akbar Mir Tariq Ahmad Mazumdar Nasreen 《Journal of Polymers and the Environment》2022,30(2):504-515
Journal of Polymers and the Environment - Niacin, an essential B-complex vitamin, used in the treatment of nonalcoholic fatty liver disease is the first perceived lipid regulating medication,... 相似文献
657.
Paris Elaine Cristina Malafatti João Otávio Donizette Sciena Camila Rodrigues Junior Luiz Ferreira Neves Zenatti Alessandra Escote Márcia Tsuyama Moreira Ailton José Freschi Gian Paulo Giovanni 《Environmental science and pollution research international》2021,28(19):23731-23741
Environmental Science and Pollution Research - Nanotechnology has been studied on environmental remediation processes to foster greater photocatalysts efficiency and reuse in wastewater. This study... 相似文献
658.
Zamora-Briseño Jesús Alejandro Améndola-Pimenta Monica Ortega-Rosas Daniel Antonio Pereira-Santana Alejandro Hernández-Velázquez Ioreni Margarita González-Penagos Carlos Eduardo Pérez-Vega Juan Antonio del Río-García Marcela Árcega-Cabrera Flor Rodríguez-Canul Rossanna 《Environmental science and pollution research international》2021,28(26):34309-34327
Environmental Science and Pollution Research - Crude oil is one of the most widespread pollutants released into the marine environment, and native species have provided useful information about the... 相似文献
659.
Borges João Tito Nakada Liane Yuri Kondo Maniero Milena Guedes Guimarães José Roberto 《Environmental science and pollution research international》2021,28(30):40460-40473
Environmental Science and Pollution Research - In a post-pandemic scenario, indoor air monitoring may be required seeking to safeguard public health, and therefore well-defined methods, protocols,... 相似文献
660.
Moroz Ivan Scapolio Luiz G. B. Cesarino Ivana Leão Alcides L. Bonanomi Giuliano 《Environmental science and pollution research international》2021,28(9):10450-10473
Environmental Science and Pollution Research - Tobacco is a worldwide-consumed product, which in addition to causing public health-related issues is responsible for the most common form of litter... 相似文献