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31.
Modeling ecological niches of species is a promising approach for predicting the geographic potential of invasive species in new environments. Argentine ants (Linepithema humile) rank among the most successful invasive species: native to South America, they have invaded broad areas worldwide. Despite their widespread success, little is known about what makes an area susceptible--or not--to invasion. Here, we use a genetic algorithm approach to ecological niche modeling based on high-resolution remote-sensing data to examine the roles of niche similarity and difference in predicting invasions by this species. Our comparisons support a picture of general conservatism of the species' ecological characteristics, in spite of distinct geographic and community contexts.  相似文献   
32.
Summary Polyterritorial polygyny in passerine birds, i.e., when already-paired males attract females in secondary territories, has been explained by male deception. Secondary females are assumed to make a poor choice, because they lack information about males' pairing status. To date, the deception hypothesis has focused mainly on the hole-nesting pied flycatcher. In this study of polyterritorial wood warblers, an open-nesting species, secondary females did not differ in number of fledged young compared with females of monogamous males, and they fledged even more young than primary females. Nest predation influenced the allocation of paternal care. Almost half of the secondary females had exclusive male assistance because nests of primary females were preyed upon.  相似文献   
33.
Objective: The aim of this study was primarily to evaluate inebriated fatally injured drivers (FIDs) according to blood alcohol concentration (BAC) in a 10-year period (2004–2013) in Autonomous Province (AP) of Vojvodina, Republic of Serbia, to analyze the efficacy of alcohol polices in the new law on road traffic safety through changes in the number of inebriated FIDs before and after implementation of the law, as well as to identify factors that influence the occurrence of FIDs with BACs above the legal limit.

Methods: All data for this retrospective study were obtained from the Centre of Forensic Medicine, Toxicology and Molecular Genetics of Clinical Centre of Vojvodina, Novi Sad. Autopsy records for each case included age, gender, BAC, type of vehicle, and date of accident (year, month, and recalculated day of the week). BAC was determined by gas chromatography with flame ionization detection. Statistical analysis was carried out by chi-square tests and Student's t test, with P < .05 as a statistical significance, and multiple binary logistic regression.

Results: Of the 354 inebriated FIDs (60% of all FIDs), the majority had BACs between of 0.031 and 0.3 mg/ml (28%), followed by those with BAC > 2.01 mg/ml (23%). The average BAC of those driving under the influence of alcohol (DUIA) for the whole period was 1.235 ± 1.00 mg/ml and the average number of DUIA/year was 35. Among the total number of FIDs there were significantly more males (93.7%; P < .001) than females (6.3%), though the distribution of intoxicated men and women was not different (P > .05). There was a statistically significant difference in the distribution of sober and inebriated FIDs according to age (P < .001) with the predominance of inebriated FIDs between 21 and 30 years. Although gender and age were found to be significant predictors of BAC above legal limit in FIDs, the area under the receiver operating characteristics (ROC) curve showed that the model had poor discrimination (ROC = 0.673). Of all observed FIDs, 65 cases per year were attributed to the first 5-year period (2004–2009) and 49 to the second 5-year (2010–2013) period, which indicates that there was no statistically significant decrease in the number of FIDs after implementation of the new law.

Conclusion: The highest number of intoxicated FIDs during the period in AP Vojvodina were mildly and completely inebriated. In the 4-year post-policy period (2010–2013), the number of FIDs and average BAC levels of inebriated FIDs did not significantly change. The abolition of a permissible BAC should be considered.  相似文献   

34.
Environmental Science and Pollution Research - A circadian variation in the cardiovascular parameters has been detected. It is plausible that the influence of the environment varies during...  相似文献   
35.

Background, aim and scope  

In an international project named MONARPOP (Monitoring Network in the Alpine Region for Persistent and other Organic Pollutants), selected chemicals in different environmental media were analysed in the years 2004 and 2005. Seventeen pesticides were chosen and analysed in humus and mineral soil in the German Alps. The samples were taken at different altitudes.  相似文献   
36.
Herbarium specimens are increasingly recognized as an important resource for conservation science and virtual herbaria are making specimens freely available to a wider range of users than ever before. Few virtual herbaria are designed with conservation use as a primary driver. Exceptionally, Brazil's Reflora Virtual Herbarium (RVH) was created to increase knowledge and conservation of the Brazilian flora. The RVH is closely integrated with the Flora of Brazil 2020 platform on which Brazil's new national Flora is under construction. Both resources are accessible via the Reflora home page and thousands of users move seamlessly between these Reflora resources. To understand how the Reflora resources are currently used and their impact on conservation science, we conducted a literature review and an online survey. We searched for publications of studies in which Reflora resources were used and publications resulting from Brazilian researchers who were part of Reflora's research and mobility program. The survey contained multiple choice questions and questions that required a written response. We targeted Reflora webpage visitors with the survey to capture a wider range of Reflora users than the literature review. Reflora resources were used for a variety of conservation-relevant purposes. Half the 806 scientific publications in which Reflora was cited and 81% of the 1069 survey respondents accessing Reflora resources mentioned conservation-relevant research outputs. Most conservation-relevant uses of the Reflora resources in scientific publications were research rather than implementation focused. The survey of Reflora users showed conservation uses and impacts of virtual herbaria were more numerous and diverse than the uses captured in the literature review. Virtual herbaria are vital resources for conservation science, but they must document use and impacts more comprehensively to ensure sustainability.  相似文献   
37.
The human communities and ecosystems of island and coastal southeast Africa face significant and linked ecological threats. Socioecological conditions of concern to communities, governments, nongovernmental organizations, and researchers include declining agricultural productivity, deforestation, introductions of non-native flora and fauna, coastal erosion and sedimentation, damage to marine environments, illegal fishing, overfishing, waste pollution, salinization of freshwater supplies, and rising energy demands, among others. Human–environment challenges are connected to longer, often ignored, histories of social and ecological dynamics in the region. We argue that these challenges are more effectively understood and addressed within a longer-term historical ecology framework. We reviewed cases from Madagascar, coastal Kenya, and the Zanzibar Archipelago of fisheries, deforestation, and management of human waste to encourage increased engagement among historical ecologists, conservation scientists, and policy makers. These case studies demonstrate that by widening the types and time depths of data sets we used to investigate and address current socioecological challenges, our interpretations of their causes and strategies for their mitigation varied significantly.  相似文献   
38.
39.
The aim of this study was to assess persistent organochlorine pollutant (POP) levels in serum collected from children (11-15 years old) working and sometimes also living at the municipal waste-disposal site in Managua, located at the shore of Lake Managua, and in nonworking children living both nearby and also far away from the waste-disposal site. The influence of fish consumption was further evaluated by assessing POPs levels in serum from young women (15-24 years old) with markedly different patterns of fish consumption from Lake Managua. 2,2-bis(4-chlorophenyl)-1,1,1-trichloro-ethane (4,4'-DDT) and 2,2-bis(4-chlorophenyl)-1,1-dichloro-ethene (4,4'-DDE), gamma-hexachlorocyclohexane (gamma-HCH), polychlorinated biphenyls, pentachlorophenol, and polychlorobiphenylols were quantified in all samples. In general, the levels observed were higher than those reported in children from developed countries, such as Germany and United States. Toxaphene, aldrin, dieldrin, and beta-HCH could not be identified in any sample. The children working at the waste-disposal site had higher levels of POPs compared with the nonworking reference groups. In children not working, there were also gradients for several POPs, according to vicinity to the waste-disposal site. Moreover, in children, as well as in young women, there were gradients according to fish consumption. The most abundant component was 4,4'-DDE, but at levels still lower than those reported in children from malarious areas with a history of recent or current application of 4,4'-DDT for vector control.  相似文献   
40.
Objectives: There are 3 standardized versions of the Detection Response Task (DRT), 2 using visual stimuli (remote DRT and head-mounted DRT) and one using tactile stimuli. In this article, we present a study that proposes and validates a type of auditory signal to be used as DRT stimulus and evaluate the proposed auditory version of this method by comparing it with the standardized visual and tactile version.

Methods: This was a within-subject design study performed in a driving simulator with 24 participants. Each participant performed 8 2-min-long driving sessions in which they had to perform 3 different tasks: driving, answering to DRT stimuli, and performing a cognitive task (n-back task). Presence of additional cognitive load and type of DRT stimuli were defined as independent variables. DRT response times and hit rates, n-back task performance, and pupil size were observed as dependent variables.

Results: Significant changes in pupil size for trials with a cognitive task compared to trials without showed that cognitive load was induced properly. Each DRT version showed a significant increase in response times and a decrease in hit rates for trials with a secondary cognitive task compared to trials without. Similar and significantly better results in differences in response times and hit rates were obtained for the auditory and tactile version compared to the visual version. There were no significant differences in performance rate between the trials without DRT stimuli compared to trials with and among the trials with different DRT stimuli modalities.

Conclusions: The results from this study show that the auditory DRT version, using the signal implementation suggested in this article, is sensitive to the effects of cognitive load on driver's attention and is significantly better than the remote visual and tactile version for auditory–vocal cognitive (n-back) secondary tasks.  相似文献   

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