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We investigated the influence and relative importance of insecticides and other agricultural stressors in determining variability in invertebrate communities in small streams in intensive soy-production regions of Brazil and Paraguay. In Paraguay we sampled 17 sites on tributaries of the Pirapó River in the state of Itapúa and in Brazil we sampled 18 sites on tributaries of the San Francisco River in the state of Paraná. The riparian buffer zones generally contained native Atlantic forest remnants and/or introduced tree species at various stages of growth. In Brazil the stream buffer width was negatively correlated with sediment insecticide concentrations and buffer width was found to have moderate importance in mitigating effects on some sensitive taxa such as mayflies. However, in both regions insecticides had low relative importance in explaining variability in invertebrate communities, while various habitat parameters were more important. In Brazil, the percent coverage of soft depositional sediment in streams was the most important agriculture-related explanatory variable, and the overall stream-habitat score was the most important variable in Paraguay streams. Paraguay and Brazil both have laws requiring forested riparian buffers. The ample forested riparian buffer zones typical of streams in these regions are likely to have mitigated the effects of pesticides on stream invertebrate communities. This study provides evidence that riparian buffer regulations in the Atlantic Forest region are protecting stream ecosystems from pesticides and other agricultural stressors. Further studies are needed to determine the minimum buffer widths necessary to achieve optimal protection.

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We present a multi-year superposed epoch study of the Sounding of the Atmosphere using Broadband Emission Radiometry nitric oxide (NO) emission data. NO is a trace constituent in the thermosphere that acts as cooling agent via infrared (IR) emissions. The NO cooling competes with storm time thermospheric heating resulting in a thermostat effect. Our study of nearly 200 events reveals that shock-led interplanetary coronal mass ejections (ICMEs) are prone to early and excessive thermospheric NO production and IR emissions. Excess NO emissions can arrest thermospheric expansion by cooling the thermosphere during intense storms. The strongest events curtail the interval of neutral density increase and produce a phenomenon known as thermospheric 'overcooling'. We use Defense Meteorological Satellite Program particle precipitation data to show that interplanetary shocks and their ICME drivers can more than double the fluxes of precipitating particles that are known to trigger the production of thermospheric NO. Coincident increases in Joule heating likely amplify the effect. In turn, NO emissions more than double. We discuss the roles and features of shock/sheath structures that allow the thermosphere to temper the effects of extreme storm time energy input and explore the implication these structures may have on mesospheric NO. Shock-driven thermospheric NO IR cooling likely plays an important role in satellite drag forecasting challenges during extreme events.

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We investigated relationships among insecticides and aquatic invertebrate communities in 22 streams of two soy production regions of the Argentine Pampas over three growing seasons. Chlorpyrifos, endosulfan, cypermethrin, and lambda-cyhalothrin were the insecticides most frequently detected in stream sediments. The Species at Risk (SPEAR) pesticide bioassessment index (SPEARpesticides) was adapted and applied to evaluate relationships between sediment insecticide toxic units (TUs) and invertebrate communities associated with both benthic habitats and emergent vegetation habitats. SPEARpesticides was the only response metric that was significantly correlated with total insecticide TU values for all three averaged data sets, consistently showing a trend of decreasing values with increasing TU values (r2=0.35 to 0.42, p-value=0.001 to 0.03). Although pyrethroids were the insecticides that contributed the highest TU values, toxicity calculated based on all insecticides was better at predicting changes in invertebrate communities than toxicity of pyrethroids alone. Crustaceans, particularly the amphipod Hyalella spp., which are relatively sensitive to pesticides, played a large role in the performance of SPEARpesticides, and the relative abundance of all crustaceans also showed a significant decreasing trend with increasing insecticide TUs for two of three data sets (r2=0.30 to 0.57, p-value=0.003 to 0.04) examined. For all data sets, total insecticide TU was the most important variable in explaining variance in the SPEARpesticides index. The present study was the first application of the SPEAR index in South America, and the first one to use it to evaluate effects of pesticides on invertebrate communities associated with aquatic vegetation. Although the SPEAR index was developed in Europe, it performed well in the Argentine Pampas with only minor modifications, and would likely improve in performance as more data are obtained on traits of South American taxa, such as pesticide sensitivity and generation time.

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BACKGROUND: Clinicians are often concerned that use of alternative treatments by Mexican American patients with diabetes competes with medical treatment. We examined the use and evaluation of alternative treatments for diabetes by a sample of these patients. METHODS: Following a descriptive qualitative design, a convenience sample of 43 low-income Mexican Americans with type 2 diabetes were interviewed. We analyzed interview transcripts for alternative treatments named, patterns of use, evaluation of those treatments, and the use of biomedical approaches. We crosschecked the results for interrater reliability. RESULTS: Herbs were mentioned as possible alternative treatments for diabetes by 84% of the patients interviewed. However, most had never or rarely tried herbs and viewed them as supplemental to medical treatments. Most said prayer influences health by reducing stress and bringing healing power to medicines. None used curanderos (traditional healers) for diabetes. Most actively used biomedical treatments and were less actively involved in alternative approaches. Statistical tests of association showed no competition between biomedical and alternative treatments, and alternative treatment activity tended to be significantly lower than biomedical. Most study participants emphasized medical treatment and only used alternative treatments as secondary strategies. Those patients very actively using alternative approaches also tended to be very actively using biomedical methods; they were using all resources they encountered. CONCLUSIONS: Traditional attitudes and beliefs were not especially important to the patients in this study and presented no barriers to medical care. For these patients, it also cannot be assumed that belief in alternative treatments and God's intervention indicate fatalism or noncompliance but instead require consideration of individual treatment behaviors.

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Studies of self-care behaviors in the management of type 2 diabetes often focus on patient knowledge and motivation, without considering the role of practitioner orientations. Using an exploratory descriptive design, we conducted open-ended interviews with 51 type 2 diabetes patients and 35 practitioners from clinics in San Antonio and Laredo, Texas. We found critical differences between patient and practitioner goals, evaluations, and strategies in diabetes management, especially regarding such key concepts as "control" and "taking care of self". Practitioners' perspectives are rooted in a clinical context, emphasizing technical considerations, whereas patients' perspectives exist within a life-world context and foreground practical and experiential considerations. These result in very different approaches to treatment. Practitioners, presuming failed treatment indicates uncooperativeness, try to inform and motivate patients. The patients we interviewed, however, understood and were committed to type 2 diabetes self-care, but lacked full access to behavioral options due to their poverty and limited social power.

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PURPOSE/OBJECTIVES: To understand impediments to receiving and reporting timely follow-up care for abnormal Pap tests among Hispanic women. DESIGN: Descriptive, qualitative. SETTING: A federally funded cancer screening clinic in urban South Texas. SAMPLE: 11 Mexican/Mexican-American women over 40 years old who appear in clinic records as "lapsed" in follow-up and 5 clinic staff members. METHODS: Semistructured, qualitative interviews regarding staff and patient concepts about cancer, cancer screening, and follow-up. Abstraction of patients' clinic charts. MAIN RESEARCH VARIABLES: Factors associated with women being classified as "lapsed" in follow-up care for abnormal Pap tests. FINDINGS: Only two patients had no follow-up, while nine eventually had follow-up, either elsewhere or after several missed appointments. Contrary to expectations, poor knowledge, lack of social support, and lack of availability of care were not factors impeding follow-up. Reluctance to be examined by a male practitioner, lack of flexibility in scheduling clinic appointments, and poor staff communication regarding appointments and the seriousness of the condition were all influences negatively affecting follow-up behavior. Nevertheless, these women went to significant lengths to comply with follow-up recommendations. CONCLUSIONS: The classification of patients' follow-up behavior as "lapsed" was not attributable to culturally based beliefs and attitudes, nor lack of knowledge and motivation, but was primarily the result of institutional features such as scheduling and record-keeping practices and policies. IMPLICATIONS FOR NURSING PRACTICE: More thorough evaluation of actual behaviors would ensure more accurate assessment of follow-up behavior in this group. More female practitioners, better communication of appointments and of the seriousness of the condition, and more flexible scheduling options would reduce the difficulty these Hispanic patients encountered in having timely follow-up care.

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Moral themes were a striking feature of the causal explanations for female cancers discussed by oncologists and patients in an ethnographic study of hospital-based cancer care in southern Mexico. These explanations integrate general biomedical explanations with everyday expectations and experiences, giving meaning to otherwise arbitrary events. Analysis of case examples shows that causal models incorporate local constructs about what constitutes a virtuous life, especially in terms of class-and gender-based values. Although patients and physicians draw on similar concepts of moral order, they apply these constructs in distinct ways. Because physicians' explanations are necessarily framed in terms of object, their causal stories employ generalized presumptions about how categories of persons behave (e.g., women, the lower class). In contrast, patients' explanations are framed in terms of subject; they are based on the specific details of their personal history. The article examines the distinct perspectives of physicians and patients, and provides an illustration of how biomedical culture articulates with the local moral constructs of a particular community.

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This paper reports findings from an ethnographic study of self-care behaviors and illness concepts among Mexican-American non-insulin dependent diabetes mellitus (NIDDM) patients. Open-ended interviews were conducted with 49 NIDDM patients from two public hospital outpatient clinics in South Texas. They are self-identified Mexican-Americans who have had NIDDM for at least 1 yr, and have no major impairment due to NIDDM. Interviews focused on their concepts and experiences in managing their illness and their self-care behaviors. Clinical assessment of their glucose control was also extracted from their medical records. The texts of patient interviews were content analyzed through building and refining thematic matrixes focusing on their causal explanations and treatment behaviors. We found patients' causal explanations of their illness often are driven by an effort to connect the illness in a direct and specific way to their personal history and their past experience with treatments. While most cite biomedically accepted causes such as heredity and diet, they elaborate these concepts into personally relevant constructs by citing Provoking Factors, such as behaviors or events. Their causal models are thus both specific to their personal history and consistent with their experiences with treatment success or failure. Based on these findings, we raise a critique of the Locus of Control Model of treatment behavior prevalent in the diabetes education literature. Our analysis suggests that a sense that one's own behavior is important to the disease onset may reflect patients' evaluation of their experience with treatment outcomes, rather than determining their level of activity in treatment.

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This paper examines the discourse of oncologists treating cancer in a provincial capital of southern Mexico. Based on an analysis of both formal interviews and observations of everyday clinical practice, it examines a set of narrative themes they used to maintain a sense of professionalism and possibility as they endeavored to apply a highly technologically dependent biomedical model in a resource-poor context. They moved between coexisting narrative frameworks as they addressed their formidable problems of translating between theory and practice. In a biomedical narrative frame, they drew on biomedical theory to produce a model of cellular dysfunction and of clinical intervention. However, limited availability of diagnostic and treatment techniques and patients inability or unwillingness to comply, presented serious constraints to the application of this model. They used a practical narrative frame to discuss the socio-economic issues they understood to be underlying these limitations to their clinical practice. They did not experience the incongruity between theory and practice as a continual challenge to their biomedical model, nor to their professional competency. Instead, through a reconciling narrative frame, they mediated this conflict. In this frame, they drew on culturally specific concepts of moral rightness and order to produce accounts that minimized the problem, exculpated themselves and cast blame for failed diagnosis and treatment. By invoking these multiple, coexisting narrative themes, the oncologists sustained an open vision of their work in which deficiencies and impotency were vindicated, and did not stand in the way of clinical practice.

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A survey was conducted to determine the distribution and determinants of environmental and blood lead levels near a conventional and several cottage lead smelters and to assess the relationship between environmental and blood lead levels in a tropical, developing-country setting. Fifty-eight households were studied in the Red Pond community, the site of the established smelter and several backyard smelters, and 21 households were studied in the adjacent, upwind Ebony Vale community in Saint Catherine Parish, Jamaica. Households were investigated, using questionnaires, soil and housedust lead measurements, and blood lead (PbB) measurements from 372 residents. Soil lead levels in Red Pond exceeded 500 parts per million (ppm) at 24% of households (maximum--18,600 ppm), compared to 0% in Ebony Vale (maximum 150 ppm). Geometric mean PbB in Red Pond, where 44% of children less than 6 years of age had PbB levels greater than or equal to 25 micrograms per deciliter (micrograms/dL), was more than twice that Ebony Vale in all age groups (p less than 0.0005). Within Red Pond, proximity to backyard smelters and to the conventional smelter were independent predictors of soil lead (p less than 0.05). Soil lead was the strongest predictor of PbB among Red Pond subjects under 12 years of age. The blood lead--soil lead relationship in children differed from that reported in developed countries; blood lead levels were higher than expected for the household-specific soil lead levels that were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

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