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241.
The purpose of this study was to understand self-reported transportation difficulty among rural older adults. We used data from the UAB Study of Aging (255 Black and 259 White), community-dwelling participants residing in rural areas. We examined the relationship of predisposing characteristics, enabling resources, and measures of need for care with self-reports of transportation difficulty. Blacks reported having more transportation difficulty than Whites (24.7% vs. 11.6%; p ≤ .05). When we introduced other variables, race differences disappeared, but there was a race by income interaction with transportation difficulty. Whites with lower incomes were more likely to have transportation difficulty than Whites with higher incomes. When data from Blacks and Whites were analyzed separately, income was the only variable associated with transportation difficulty among Whites. Among Blacks, income was not related to transportation difficulty but several variables other than income (age, gender, marital status, MMSE scores and depression) were.  相似文献   
242.
Volunteerism makes critical contributions to individual lives and society as a whole. However, to date, few studies have investigated volunteerism within Latino communities, a large and growing US population. The aim of this study was to understand how non-metropolitan US Latinos perceive volunteerism, as well as to determine what motivates and what deters their participation in volunteer programs. Our research team conducted six focus groups with 36 Latina women living in the State of Illinois. The focus groups covered topics such as the definition of volunteerism, participation motives and barriers, personal volunteer experience, and Latino culture, community, and organizations. We also assessed demographic information. Results from this study indicate that Latinas have a unique understanding of the concept of volunteerism. Participants associated everyday “helping” with volunteerism, establishing commonplace forms of aid as perhaps a “Latino way of volunteering.” We found time-consuming activities such as family responsibilities and work to be deterrents to Latinas participating in more formal volunteer activities.  相似文献   
243.
Carbon tetrachloride is a degreasing agent that was used at the Rocky Flats Plant (RFP) in Colorado to clean product components and equipment. The chemical is considered a volatile organic compound and a probable human carcinogen. During the time the plant operated (1953-1989), most of the carbon tetrachloride was released to the atmosphere through building exhaust ducts. A smaller amount was released to the air via evaporation from open-air burn pits and ground-surface discharge points. Airborne releases from the plant were conservatively estimated to be equivalent to the amount of carbon tetrachloride consumed annually by the plant, which was estimated to be between 3.6 and 180 Mg per year. This assumption was supported by calculations that showed that most of the carbon tetrachloride discharged to the ground surface would subsequently be released to the atmosphere. Atmospheric transport of carbon tetrachloride from the plant to the surrounding community was estimated using a Gaussian Puff dispersion model (RATCHET). Time-integrated concentrations were estimated for nine hypothetical but realistic exposure scenarios that considered variation in lifestyle, location, age, and gender. Uncertainty distributions were developed for cancer slope factors and atmospheric dispersion factors. These uncertainties were propagated through to the final risk estimate using Monte Carlo techniques. The geometric mean risk estimates varied from 5.2 x 10(-6) for a hypothetical rancher or laborer working near the RFP to 3.4 x 10(-9) for an infant scenario. The distribution of incremental lifetime cancer incidence risk for the hypothetical rancher was between 1.3 x 10(-6) (5% value) and 2.1 x 10(-5) (95% value). These estimates are similar to or exceed estimated cancer risks posed by releases of radionuclides from the site.  相似文献   
244.
This research investigated infants’ (16 and 20 months) use of category information in responding to references to absent objects. Infants were asked to find an object in the box (e.g., “Find an apple!”). When allowed to search, they found either an object from the mentioned category (a plastic apple) or a different object. Infants in both age groups searched again in the box trying to find another object more often on nonreferent than on referent trials (Experiment 1). However, when nonreferents were categorically related to referents, only older infants detected a mismatch and searched again (Experiment 2). These findings suggest that infants use category knowledge when processing references to absent objects.  相似文献   
245.
Abstract

Objective: A Haddon Matrix analysis was used to systematically review literature evaluating college campus sexual assault prevention programs to identify research gaps and intervention opportunities. Methods: Articles included were published from January 1, 2001 to December 31, 2017; indexed in PubMed, PsycInfo, or Scopus; involving English-speaking undergraduate students in the US; with experimental or quasi-experimental design. Results: All 31 eligible studies evaluated educational programing; all relied on self-report measures; and three-quarters had follow-up periods ≤ 6?months. Significant positive effects were reported by 6 of 10 studies that measured bystander behavior, 6 of 10 that educated potential victims and assessed victimization, and one of four that educated potential perpetrators and measured perpetration. Conclusion: The Haddon Matrix analysis identified the need for interventions that address perpetrators and the post-assault period, as well as studies of the impact of enforcing existing policies and new environmental and situational approaches to sexual assault prevention.  相似文献   
246.
This study aimed at developing a predictive model that captures the influences of a variety of agricultural and environmental variables and is able to predict the concentrations of enteric bacteria in soil amended with untreated Biological Soil Amendments of Animal Origin (BSAAO) under dynamic conditions. We developed and validated a Random Forest model using data from a longitudinal field study conducted in mid-Atlantic United States investigating the survival of Escherichia coli O157:H7 and generic E. coli in soils amended with untreated dairy manure, horse manure, or poultry litter. Amendment type, days of rain since the previous sampling day, and soil moisture content were identified as the most influential agricultural and environmental variables impacting concentrations of viable E. coli O157:H7 and generic E. coli recovered from amended soils. Our model results also indicated that E. coli O157:H7 and generic E. coli declined at similar rates in amended soils under dynamic field conditions.The Random Forest model accurately predicted changes in viable E. coli concentrations over time under different agricultural and environmental conditions. Our model also accurately characterized the variability of E. coli concentration in amended soil over time by providing upper and lower prediction bound estimates. Cross-validation results indicated that our model can be potentially generalized to other geographic regions and incorporated into a risk assessment for evaluating the risks associated with application of untreated BSAAO. Our model can be validated for other regions and predictive performance also can be enhanced when data sets from additional geographic regions become available.  相似文献   
247.
248.
This paper discusses a methodology used for a qualitative cost–benefit evaluation of a complex, emergent program. Complex, emergent programs, where implementation varies considerably over time and across sites to respond to local needs and opportunities, present challenges to conventional methods for cost–benefit evaluation. Such programs are characterized by: ill-defined boundaries of what constitutes the intervention, and hence the resources used; non-standardized procedures; differing short-term outcomes across projects, even within the same long-term goals; and outcomes that are the result of multiple factors and co-production, making counter-factual approaches to attribution inadequate and the use of standardized outcome measures problematic. The paper discusses the advantages and limitations of this method and its implications for cost–benefit evaluation of complex programs.  相似文献   
249.
The effects of urban disturbance are critical to understand, as the majority of the world??s population now resides in urban centers. For example, urbanization often leads to reduced species diversity at the expense of a few urban-adapted taxa. However, it remains unclear why some taxa thrive following human disturbance whereas others do poorly. The western black widow spider, Latrodectus hesperus, thrives in disturbed, urban habitat??often forming dense aggregations (i.e., infestations) relative to typical low-density, desert populations. We examined the population dynamics of ten black widow aggregations spread across metropolitan Phoenix, AZ, during the peak of the breeding season (June?CAugust). Here we show that prey abundance, female mass, web volume and population density exhibit minimal temporal variation across the breeding season, but that prey abundance, female mass and population density show significant spatial variation across the ten urban aggregations. Our measure of prey abundance and foraging success, the number of prey carcasses found in black widow webs, shared a strong positive relationship with female mass and population density, but not with web volume. Surprisingly, female mass, web volume and population density were not correlated with each other. The abiotic variables we measured at each site did a poor job of explaining black widow population parameters, although we did find a marginal trend for more recent developments to harbor denser black widow aggregations. Our findings support the generalization that urbanization heightens spatial variation, and we suggest that local urban prey abundance is influential in promoting urban infestations full of heavy, fecund female black widows. Studies of the population ecology of urban pests are necessary to identify the mechanisms allowing some species to thrive following human disturbance while much native biodiversity is lost following urbanization.  相似文献   
250.
Studies have shown that conflict over parent–child relationships are frequently at the root of stepfamily dissolution and that the stepmother/daughter relationship is the most problematic stepfamily relationship. This paper explores the stepmother–daughter relationship in the family where the biological mother is an active parent and discusses the unique challenges and internal conflicts that the stepmother confronts on entry into the family and its web of preexisting relationships and transferences. “An internal parental stance” which underlies “good enough” stepmothering is conceptualized and the complex psychological processes which underlie this achievement are explored in this paper along with implications for clinical strategies. The term good enough stepmothering is a play on Winnicott’s concept of the good-enough mother—the maternal figure whose attunement to her child enables her to adapt appropriately to her child’s stage of life thus allowing an optimal environment for the child’s development.  相似文献   
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