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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   
113.
A forecasting system is set up to improve the diagnosis in a Condition Monitoring Programme of a critical turbine placed at an industrial plant. The system is based on a statistical model in a State Space framework, such that the local mean level of the vibration state of the equipment is estimated directly from the data, based on a continuous-time set up. This model is combined with a cost model in Conditioned Monitoring, by which the time of preventive replacement is produced when the minimum of the expected cost per unit of time is reached into the future. Such measure is a combination of the costs of failure, the costs of a preventive replacement and the probabilities of reaching the alarm levels fixed by some criteria. The system is estimated by Maximum Likelihood and thoroughly tested on the equipment. The main tests relate to statistical properties of the model residuals and a comprehensive comparison with an alternative system, namely a linear trend regression model in continuous time. The system produced a reasonable forecasting performance and sensible time of preventive replacement prediction and outperformed the alternative forecasting system.  相似文献   
114.
Latent period, burst time, and burst size, kinetic parameters of phage infection characteristic of a given phage/host system, have been measured for a wide variety of lactic acid bacteria. However, most studies to date were conducted in optimal growth conditions of host bacteria and did not consider variations due to changes in external factors. In this work, we determined the effect of temperature, pH, and starvation on kinetic parameters of phages infecting Lactobacillus paracasei, Lactobacillus plantarum, and Leuconostoc mesenteroides. For kinetics assessment, one-step growth curves were carried out in MRS broth at optimal conditions (control), lower temperature, pH 6.0 and 5.0 (MRS6 and MRS5, respectively), or in medium lacking carbon (MRSN) or nitrogen (MRSC) sources. Phage infection was progressively impaired as environmental conditions were modified from optimal. At lower temperature or pH, infection was delayed, as perceived by longer latent and burst times. Burst size, however, was lower, equal or higher than for controls, but this effect was highly dependent on the particular phage–host system studied. Phage infection was strongly inhibited in MRSC, but only mildly impaired in MRSN. Nevertheless, growth of all the bacterial strains tested was severely compromised by starvation, without significant differences between MRSC and MRSN, indicating that nitrogen compounds are specifically required for a successful phage infection, beyond their influence on bacterial growth.  相似文献   
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Environmental Science and Pollution Research - Oil sludge washing (OSW) with surfactants and co-solvents is used to recover the oil, and this process leaves some residuals (sediments and surfactant...  相似文献   
116.
Protected area networks help species respond to climate warming. However, the contribution of a site's environmental and conservation-relevant characteristics to these responses is not well understood. We investigated how composition of nonbreeding waterbird communities (97 species) in the European Union Natura 2000 (N2K) network (3018 sites) changed in response to increases in temperature over 25 years in 26 European countries. We measured community reshuffling based on abundance time series collected under the International Waterbird Census relative to N2K sites’ conservation targets, funding, designation period, and management plan status. Waterbird community composition in sites explicitly designated to protect them and with management plans changed more quickly in response to climate warming than in other N2K sites. Temporal community changes were not affected by the designation period despite greater exposure to temperature increase inside late-designated N2K sites. Sites funded under the LIFE program had lower climate-driven community changes than sites that did not received LIFE funding. Our findings imply that efficient conservation policy that helps waterbird communities respond to climate warming is associated with sites specifically managed for waterbirds.  相似文献   
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Cylindrical cyclone media separators using a suspended calcite separation media simulating industrial scale operations are demonstrated to effectively separate a wide variety of forms and a greater range of particle sizes of plastics by density than presently recycled. Purities of plastic products and recoveries obtained from mixed plastic wastes are comparable to those reported for established separations. Products of ≈100% purity with recoveries of >99% were obtained for high density fractions and >98% purities and recoveries for the low density fractions. Cyclonic centrifugal forces and/or the fine particle size of the separation media appear to minimize hydroscopic and particle shape effects.A mathematical model is proposed for defining plastic waste feed rates and treatable particle size ranges for the LARCODEMS media separator.Waste plastic separations yielded Ecart probable (Ep) values ?0.024 for a water only separation media. The Ep for 1.1 g cm?3 separation medias was <0.032 with minimal to no variation in values for 1–8 mm particle sizes. Variation in the quality of separations is shown to be minimal with <72 μm, <45 μm and <2 μm media particle sizes. Media density offset created varied according to particle size.  相似文献   
119.
Despite the importance of neotropical cloud forests as providers of ecosystem services to society, they are one of the most threatened ecosystems in the world. We analysed the importance of three cloud forest reserves in central Colombia as providers of ecosystem services, as well as the social support to conservation actions in these ecosystems through willingness to pay (WTP) and willingness to give up time (WTT) estimates. Our results highlight the high commitment of all users of the cloud forest areas towards the conservation of the ecosystem services provided by these strategic ecosystems. We found that the most important perceived ecosystem services were water supply and habitat maintenance for species. Our findings also suggest that the respondents’ ecological knowledge (measured as the awareness of the ecosystem services supplied by cloud forests) was an important factor in determining both WTP and WTT for conserving cloud forests. Moreover, our results indicate that WTT should be a viable technique to explore individual preferences of different stakeholders towards conservation activities in cloud forests. Based on our results, we propose a conservation strategy of cloud forests that considers different users’ socio-economic and environmental characteristics, in which both experimental and experiential knowledge should be incorporated in order to promote collective action.  相似文献   
120.
CO2 and SO2 are some of the main polluting gases emitted into atmosphere in combustion processes using fossil fuel for energy production. The former is one of the major contributors to build-up the greenhouse effect implicated in global climate change and the latter produces acid rain. Oxy-fuel combustion is a technology, which consists in burning the fuel with a mix of pure O2 and recirculated CO2. With this technology the CO2 concentration in the flue gas may be enriched up to 95%, becoming possible an easy CO2 recovery. In addition, oxy-fuel combustion in fluidized beds allows in situ desulfurization of combustion gases by supplying calcium based sorbent.In this work, the effect of the principal operation variables affecting the sulfation reaction rate in fluidized bed reactors (temperature, CO2 partial pressure, SO2 concentration and particle size) under typical oxy-fuel combustion conditions have been analyzed in a batch fluidized bed reactor using a limestone as sorbent. It has been observed that sulfur retention can be carried out by direct sulfation of the CaCO3 or by sulfation of the CaO (indirect sulfation) formed by CaCO3 calcination. Direct sulfation and indirect sulfation operating conditions depended on the temperature and CO2 partial pressure. The rate of direct sulfation rose with temperature and the rate of indirect sulfation for long reaction times decreased with temperature. An increase in the CO2 partial pressure had a negative influence on the sulfation conversion reached by the limestone due to a higher temperature was needed to work in conditions of indirect sulfation. Thus, it is expected that the optimum temperature for sulfur retention in oxy-fuel combustion in fluidized bed reactors be about 925–950 °C. Sulfation reaction rate rose with decreasing sorbent particle size and increasing SO2 concentration.  相似文献   
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