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61.
Kin-based patterns of associations are often observed in group living mammals. Colonies of forest-living big brown bats (Eptesicus fuscus) exhibit fission–fusion roosting behavior and female philopatry. Within a roosting area of forest, adult females are distributed into several subgroups roosting in different trees during the day. At night, adult females leave the roost subgroups to forage and, upon return to the roosting area at dawn, both the individual composition and location of subgroups often change. Individuals exhibit nonrandom roosting associations, and we hypothesized that genetic relationships would influence roosting associations. We determined (1) whether the strength of roosting associations between pairs of bats (based on radiotelemetry) was correlated with relatedness, (2) whether individuals that roosted together in roost subgroups were more related than by chance, and (3) from roost subgroups, the pairs of bats that roosted nonrandomly and whether the proportion of related pairs was higher than expected at random. Relatedness measures were based on microsatellite genotyping and mitochondrial DNA sequences. We found from all analyses that roosting associations were not influenced by relatedness or matrilineal relationships. These results provide clear evidence that, contrary to other mammals, kinship does not mediate roosting associations within forest living big brown bats that exhibit fission–fusion roosting behavior.  相似文献   
62.
Biomarker responses and histopathological lesions have been documented in laboratory mammals exposed to elevated concentrations of lead and cadmium. The exposure of white-footed mice (Peromyscus leucopus) to these metals and the potential associated toxic effects were examined at three contaminated sites in the Southeast Missouri Lead Mining District and at a reference site in MO, USA. Mice from the contaminated sites showed evidence of oxidative stress and reduced activity of red blood cell δ-aminolevulinic acid dehydratase (ALAD). Histological examinations of the liver and kidney, cytologic examination of blood smears, and biomarkers of lipid peroxidation and DNA damage failed to show indications of toxic effects from lead. The biomagnification factor of cadmium (hepatic concentration/soil concentration) at a site with a strongly acid soil was 44 times the average of the biomagnification factors at two sites with slightly alkaline soils. The elevated concentrations of cadmium in the mice did not cause observable toxicity, but were associated with about a 50% decrease in expected tissue lead concentrations and greater ALAD activity compared to the activity at the reference site. Lead was associated with a decrease in concentrations of hepatic glutathione and thiols, whereas cadmium was associated with an increase. In addition, to support risk assessment efforts, we developed linear regression models relating both tissue lead dosages (based on a previously published a laboratory study) and tissue lead concentrations in Peromyscus to soil lead concentrations.  相似文献   
63.
Lead in paint continues to be a threat to children's health in cities across the United States, which means there is an ongoing need for testing and analysis of paint. This ongoing analytical effort and especially development of new methods continue to drive the need for diagnostic testing materials that provide the analytical challenges of real-world paints. To this end, 31 different types of paint test materials were developed and prepared. Preparation of the materials included development of lead-containing paint films yielding an overall relative standard error for one individual test sample being less than 10%. The 31 diagnostic test materials prepared with these paint films included two lead pigments; lead concentrations from nominally 0 to 2.0 mg lead/cm(2) (0 to 5% lead by weight); overlayers of both "lead-free," oil-based and water-based paints; Al, Ba, and Mg as potential chemical interferents; red and black potential color interferents; and substrates of wood, metal, masonry, and plaster. These materials challenge each step in method development and evaluation, including paint sample collection and preparation, lead extraction, and measurement of solubilized lead. When the materials were used to test performance of a new lead-in-paint testing method based on extraction using a rotor/stator method and measurement using turbidimetry, the results agreed to within ±20% of the expected lead values for 30 out of 31 of the diagnostic test materials, thereby demonstrating their levels of quality and utility.  相似文献   
64.

Objective

To describe traumatic brain injury (TBI) among injured roadway users. Aim 1 assessed the association of age, gender, alcohol/drug use, safety equipment use, type of roadway user, metropolitan area, and primary payer with motor vehicle-related TBI outcome. Aim 2 assessed the relationship of motor vehicle-related TBI and risk/protective factors with medical and economic outcomes.

Methods

Population-level hospital and trauma databases from the Ohio Hospital Association and Ohio Department of Public Safety, respectively, were probabilistically linked for 2003 through 2006. Injured roadway users (motor vehicle occupants, motorcyclists, bicyclists, pedestrians, and others) were assessed for TBI, ventilator use, intensive care unit (ICU) admission, injury severity score (ISS), need for rehabilitation, death, and total hospital charges.

Results

The odds of a motor vehicle-related TBI were greater among those not using safety equipment (OR = 1.56). The interactions of alcohol/drug use by gender and of alcohol/drug use by location were significant. Sustaining a TBI increased the odds of requiring ventilation (OR = 3.66), being admitted to the ICU (OR = 2.51), having a high ISS (OR = 4.24), requiring rehabilitation (OR = 2.22), or death (OR = 2.52). When compared with a non-TBI, total hospital charges increased by a factor of 1.35 for a TBI. Hospital charges were $46,441 on average for individuals who sustained a TBI, whereas mean hospital charges were $32,614 for patients with a non-TBI.

Conclusions

Among injured roadway users, individuals who sustain a TBI are more likely to require extensive medical care and have injuries resulting in death.

Impact on industry

Prevention strategies aimed at reducing alcohol use and increasing safety device use should be encouraged to reduce the burden of TBI.  相似文献   
65.
Faith-based organizations (FBOs) have played a significant role in environment-related forms of development and governance in Melanesia, including the Solomon Islands. Yet despite their centrality, there remain significant gaps in understandings of processes and outcomes associated with FBO engagement in environment-related development interventions. This paper addresses this gap by analysing the place of the Christian Fellowship Church (CFC), an indigenous FBO active in plantation forestry (and other activities) in the Western Province in the Solomon Islands. We find that the CFC possesses impressive income-generating potential and political networks; however this does not always translate into positive social, economic or environmental outcomes at the village level. While FBOs such as CFC are often championed as playing an important role in environmental governance in an under-resourced nation state, the reality is that they can fall well short in delivering appropriate outcomes for poor communities or the environment despite, and because of, their close ties to target communities.  相似文献   
66.
Landscape‐scale alterations that accompany urbanization may negatively affect the population structure of wildlife species such as freshwater turtles. Changes to nesting sites and higher mortality rates due to vehicular collisions and increased predator populations may particularly affect immature turtles and mature female turtles. We hypothesized that the proportions of adult female and immature turtles in a population will negatively correlate with landscape urbanization. As a collaborative effort of the Ecological Research as Education Network (EREN), we sampled freshwater turtle populations in 11 states across the central and eastern United States. Contrary to expectations, we found a significant positive relationship between proportions of mature female painted turtles (Chrysemys picta) and urbanization. We did not detect a relationship between urbanization and proportions of immature turtles. Urbanization may alter the thermal environment of nesting sites such that more females are produced as urbanization increases. Our approach of creating a collaborative network of scientists and students at undergraduate institutions proved valuable in terms of testing our hypothesis over a large spatial scale while also allowing students to gain hands‐on experience in conservation science.  相似文献   
67.
New global initiatives to restore forest landscapes present an unparalleled opportunity to reverse deforestation and forest degradation. Participatory monitoring could play a crucial role in providing accountability, generating local buy in, and catalyzing learning in monitoring systems that need scalability and adaptability to a range of local sites. We synthesized current knowledge from literature searches and interviews to provide lessons for the development of a scalable, multisite participatory monitoring system. Studies show that local people can collect accurate data on forest change, drivers of change, threats to reforestation, and biophysical and socioeconomic impacts that remote sensing cannot. They can do this at one‐third the cost of professionals. Successful participatory monitoring systems collect information on a few simple indicators, respond to local priorities, provide appropriate incentives for participation, and catalyze learning and decision making based on frequent analyses and multilevel interactions with other stakeholders. Participatory monitoring could provide a framework for linking global, national, and local needs, aspirations, and capacities for forest restoration.  相似文献   
68.
This article brings to light one aspect of alternative agri-food practices by exploring the values and meanings domestic food producers associate with their actions, thereby making a small contribution to increasing understanding of the act of urban backyard food production. While Australian backyards have long been productive spaces, there has been little examination of this phenomenon in the Australian context. Limited quantitative data give some insight into the extent of domestic production, and while there is an increasing interest in certain aspects of the local food system, including community gardens and farmers markets, there is a dearth of literature that explores the contemporary act of domestic production. This work seeks to situate the act of domestic production within the broader movement calling for change within the global food system, particularly that being articulated by the food sovereignty movement. Drawing on Gibson–Graham's diverse economies framework, and through interviews with eight domestic food producers in one Australian city, this work finds that the act of growing food at home offers space for hope – where small acts can be seen as part of the broader food sovereignty movement seeking to remake our food system.  相似文献   
69.
Standard evaluations of air quality models rely heavily on a direct comparison of monitoring data matched with the model output for the grid cell containing the monitor's location. While such techniques may be adequate for some applications, conclusions are limited by such factors as the sparseness of the available observations (limiting the number of grid cells at which the model can be evaluated) and the incommensurability between volume-averages and pointwise observations. We examine several sets of simulations to illustrate the effect of incommensurability in a variety of cases distinguished by the type and extent of spatial correlation present. Block kriging, a statistical method which can be used to address the issue, is then demonstrated using the simulations. Lastly, we apply this method to actual data and discuss the practical importance of understanding the impact of spatial correlation structure and incommensurability.  相似文献   
70.
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