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151.
Bushmeat is an important resource in the livelihoods of many rural communities in sub-Saharan Africa and may be a crucial safety-net for the most vulnerable households, especially during times of economic hardship. However, little is known about the impacts of wildlife depletion on these functions. This study quantifies the role of bushmeat in diversified rural household economies in a wildlife depleted forest-farm landscape in Ghana, assessing its importance overall, as well as differentiated by the relative vulnerability of households. Using repeat socioeconomic questionnaires (N=787) among 63 households over a one-year period, the following hypotheses were tested: (a) vulnerable households harvest more bushmeat; (b) bushmeat contributes a greater proportion of household production in vulnerable households; (c) bushmeat is more important for cash income than consumption in vulnerable households; and (d) bushmeat sales are more important for vulnerable households. The bushmeat harvest value averaged less than US$1.0 per day for 89% of households and comprised less than 7% of household production value. Household wealth and gender of the household head had little effect on the importance of bushmeat. However, bushmeat harvest and sales were highest during the agricultural lean season. Overall, most harvested bushmeat (64%) was consumed, enabling households to spend 30% less on meat/fish purchases. These findings suggest that, despite heavily depleted wildlife and diversified livelihoods, bushmeat continues to have an important role in rural livelihoods by acting as a safety net for income smoothing and reducing household expenditure during times of economic hardship.  相似文献   
152.

Objective:

The purpose of this study was to describe the prevalence of acanthosis nigricans (AN) and to quantify its association with dysglycemia in an ethnically diverse group of eighth‐grade students.

Design and Methods:

Data were collected in 2003 from a cross‐sectional study of students from 12 middle schools in three US states. Sex, race/ethnicity, and pubertal status were self‐reported. Anthropometric measures were recorded. Trained staff identified the presence and severity of AN by inspection of the back of the neck. Fasting and 2 h blood samples were analyzed for impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and high‐risk glycated hemoglobin (A1C), respectively, defined as ≥100 mg/dl, ≥140 mg/dl, and ≥ 5.7‐6.4%.

Results:

Overall, 25.0%, 58.2%, and 16.8% were Black, Hispanic, and White, respectively. AN was present among 406/1,438 (28.2%) of students: 39% among Black, 30% among Hispanic, and 5.4% among White. IGT and high‐risk A1C were present among 2.1%, and 12.4%, respectively. In multivariate logistic modeling after adjusting for gender, family history of diabetes, BMI percentile, and pubertal staging, the presence (vs. absence) of AN was associated with a 59% increased likelihood of high‐risk A1C: (P = 0.04), twice the likelihood of IGT (P = 0.06), and 47% greater likelihood of IGT/IFG combined (P < 0.0001). Adjustment for insulin attenuated the ORs by 25‐70%.

Conclusion:

In a racially/ethnically diverse sample of US adolescents, AN was common, occurring in 28% of the sample. AN was associated with a 50‐100% increased likelihood of dysglycemia even after consideration of established diabetes risk factors.  相似文献   
153.
In analyzing time-locked event-related potentials (ERPs), many studies have focused on specific peaks and their differences between experimental conditions. In theory, each latency point after a stimulus contains potentially meaningful information, regardless of whether it is peak-related. Based on this assumption, we introduce a new concept which allows for flexible investigation of the whole epoch and does not primarily focus on peaks and their corresponding latencies. For each trial, the entire epoch is partitioned into event-related fixed-interval areas under the curve (ERFIAs). These ERFIAs, obtained at single trial level, act as dependent variables in a multilevel random regression analysis. The ERFIA multilevel method was tested in an existing ERP dataset of 85 healthy subjects, who underwent a rating paradigm of 150 painful and non-painful somatosensory electrical stimuli. We modeled the variability of each consecutive ERFIA with a set of predictor variables among which were stimulus intensity and stimulus number. Furthermore, we corrected for latency variations of the P2 (260 ms). With respect to known relationships between stimulus intensity, habituation, and pain-related somatosensory ERP, the ERFIA method generated highly comparable results to those of commonly used methods. Notably, effects on stimulus intensity and habituation were also observed in non-peak-related latency ranges. Further, cortical processing of actual stimulus intensity depended on the intensity of the previous stimulus, which may reflect pain-memory processing. In conclusion, the ERFIA multilevel method is a promising tool that can be used to study event-related cortical processing.  相似文献   
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The remarkable success of immune therapies emphasizes the need for immune‐competent cancer models. Elegant genetically engineered mouse models of a variety of cancers have been established, but their effective use is limited by cost and difficulties in rapidly generating experimental data. Some mouse cancer cell lines are transplantable to immunocompetent host mice and have been utilized extensively to study cancer immunology. Here, we describe the Yale University Mouse Melanoma (YUMM) lines, a comprehensive system of mouse melanoma cell lines that are syngeneic to C57BL/6, have well‐defined human‐relevant driver mutations, and are genomically stable. This will be a useful tool for the study of tumor immunology and genotype‐specific cancer biology.  相似文献   
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There is extensive evidence for an association between an attentional bias towards emotionally negative stimuli and vulnerability to stress-related psychopathology. Less is known about whether selective attention towards emotionally positive stimuli relates to mental health and stress resilience. The current study used a modified Dot Probe task to investigate if individual differences in attentional biases towards either happy or angry emotional stimuli, or an interaction between these biases, are related to self-reported trait stress resilience. In a nonclinical sample (N = 43), we indexed attentional biases as individual differences in reaction time for stimuli preceded by either happy or angry (compared to neutral) face stimuli. Participants with greater attentional bias towards happy faces (but not angry faces) reported higher trait resilience. However, an attentional bias towards angry stimuli moderated this effect: The attentional bias towards happy faces was only predictive for resilience in those individuals who also endorsed an attentional bias towards angry stimuli. An attentional bias towards positive emotional stimuli may thus be a protective factor contributing to stress resilience, specifically in those individuals who also endorse an attentional bias towards negative emotional stimuli. Our findings therefore suggest a novel target for prevention and treatment interventions addressing stress-related psychopathology.  相似文献   
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