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292.
Household‐level interview data from a probability sample survey conducted in the northeastern Ecuadorian Amazon in 1990 are used to examine the determinants of income and assets among migrant farmers in the agricultural frontier. Multivariate analysis indicates that size of plot owned, proximity to markets, duration of residence, quality of soil, receipt of technical assistance, off‐farm employment and initial wealth positively influence current household income and wealth. More land in cattle pasture is also associated with higher status. Some settlers are prospering relative to others despite variable soil quality, unsustainable land uses, geographic isolation, apparent scarcity of labor, and lack of supportive infrastructure. The article closes with a discussion of implications for policies to assist small farmers, with some consideration of the potential ecological consequences of farmers’ activities.  相似文献   
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This study investigated the influences of ethnicity, socioeconomic status, and ethnic peer group composition on awareness and internalization of socially sanctioned standards of appearance using the Sociocultural Attitudes Towards Appearance Questionnaire (SATAQ). The researchers surveyed a convenience sample of 208 adolescent females at an ethnically diverse urban high school. Statistical analyses found that ethnicity influenced awareness of socially sanctioned standards of appearance but the effects of ethnicity varied by level of caregiver educational attainment. Ethnicity and caregiver educational attainment together accounted for variance in the internalization of these standards. Moreover, African American girls with ethnically heterogeneous peer groups had significantly higher awareness and internalization scores than those without mixed friends. These findings highlight the importance of multiple ecological factors in assessing risk for disturbed body image and eating disorders. Ethnicity remains an important predictor of disturbed body image but should be treated as a dynamic, rather than a fixed risk factor.  相似文献   
296.
Expanded school mental health (ESMH) programs offer a comprehensive range of mental health services (evaluation, therapy, case management) to youth in special and regular education. Research is needed to document that these programs are in fact providing quality care to youth and leading to enhanced outcomes. In this exploratory study, focus groups were conducted with high school students receiving mental health services and students not receiving services, therapists, parents, administrators, and health care staff to gauge the quality and effectiveness of an ESMH program. It was difficult to schedule parents for group sessions; thus, interviews also were conducted with this group. Focus groups and interviews were effective methods for understanding strengths, areas for improvement, and outcomes for our ESMH program. Participants reported that therapy served as a protective factor, enhancing physical and mental health and reducing risk for teenagers. Ideas for improving clinical practice were developed from study results.  相似文献   
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The suicide death rate in New Mexico is consistently higher than the national rate. Among adolescents, suicide is the third leading cause of death nationally, but in New Mexico it is the second leading cause of death. This study describes the pattern of adolescent suicide deaths in New Mexico. We conducted a retrospective review of all medical examiner autopsies for adolescent suicides (ages 20 years and younger) in New Mexico from 1990-1994. Records were reviewed for demographics and possible contributing factors such as depression, previous attempts, and alcohol and drug use. We identified 184 suicide deaths among children and adolescents ages 9-20 years for an overall rate of 12.9 per 100,000. Our rates for ages 5-9 years (0.2), 10-14 years (3.8), and 15-19 years (22.3) are over twice the U. S. rates. Suicide deaths resulted primarily from firearms (67%), hanging (16%), poisoning (6%), inhalation (4%), and other methods (7%). Method varied by ethnicity (p = .01) and gender (p = .03); males and non-Hispanic Whites were overrepresented among firearm deaths. Firearm ownership was known in 60 (48%) of the firearm deaths. Of these, 53% of the firearms belonged to a family member, 25% to the decedent, and 22% to a friend. Over one-third of decedents (41%) experienced mental disorders, primarily depressed mood and clinical depression. Previous suicide attempts were noted for 15% of the decedents. Some 50% of the decedents had alcohol or drugs present at the time of death; among American Indians/Alaska Natives, 74% had drugs or alcohol present (p = .003). Targeted interventions are needed to reduce adolescent suicide in New Mexico. We suggest raising awareness about acute and chronic contributing factors to suicide; training physicians to look for behavioral manifestations of depression; and involving physicians, teachers, and youth activity leaders in efforts to limit firearm accessibility, such as advising parents to remove firearms from their households.  相似文献   
298.
A reference standard for gamma-hydroxybutyric acid (GHB) free acid is not commercially available, making its analysis in forensic exhibits more difficult. GHB free acid is typically encountered in aqueous solution and in the presence of the lactone, gamma-butyrolactone (GBL), presenting difficulty in Fourier transform infrared (FT-IR) analysis. The strong infrared (IR) absorptivity of the GBL carbonyl band, the shifting of the GBL carbonyl band in aqueous solutions, and the position of the O-H bend for water can mask the main carbonyl band for GHB free acid. Model solutions of beta-hydroxybutyric acid (BHB) and GBL were studied in order to further understand the masking of the GHB free acid carbonyl band in FT-IR analysis. The use of second derivative FT-IR spectroscopy was shown to provide resolution of the free acid carbonyl band, and a presumptive test for GHB free acid was developed and applied. An extension of this work included preparing, for use as a standard reference material, small amounts (< or = 10 mg) of GHB free acid. Preparation was based on the instantaneous reaction of GHB's sodium salt with a stoichiometric amount of hydrochloric acid in aqueous solution, and subsequent isolation of the free acid in neat liquid form. Both FT-IR and proton nuclear magnetic resonance spectra of the neat reference material were obtained and used to verify its identity. The isolation of GHB free acid from actual forensic exhibits is also presented, with identity confirmation using FT-IR.  相似文献   
299.
We have investigated the susceptibility of degraded human hair shaft samples to contamination by exogenous sources of DNA, including blood, saliva, skin cells, and purified DNA. The results indicate that on the whole hair shafts are either largely resistant to penetration by contaminant DNA, or extremely easy to successfully decontaminate. This pertains to samples that are both morphologically and biochemically degraded. We suggest that this resistance to the incorporation of contaminant DNA relates to the hydrophobic and impermeable nature of the keratin structures forming the hair shaft. Therefore, hair samples represent an important and underestimated source of DNA in both forensic and ancient DNA studies.  相似文献   
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The current study found that African American residents of Oxford House (OH) used Narcotics Anonymous (NA) at high rates, and that both OH and NA strongly contributed to abstinent social networks. Having siblings and other family members in one's network predicted substance use among network members, whereas spouses, parents, and children did not have an effect on the rate of substance use. These findings suggest that OH and NA may be effective sources of abstinent social support for African Americans recovering from substance abuse. However, family members are well represented in the support networks of African Americans in OH.  相似文献   
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