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Community-based management is increasingly viewed as the most appropriate arrangement for promoting sustainable development of natural resources. A common assumption is that the values of community members, often assumed to be homogeneous, foster successful outcomes. However, analysts often treat these values and their homogeneity as exogenous factors, ignoring the community's potential role in managing members' values. This study of community-based forest management in two southern Indiana sites examines how the members of the two communities created institutions to screen, maintain, and defend their values. Analysis reveals that different institutions shaped members' preferences and led to different levels of community stability, conflict management, and natural resource condition. We argue that understanding community-based management processes and outcomes requires careful attention to how institutions facilitate or hamper the construction of community members' values.  相似文献   

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Background

Health communication campaigns – involving mass media and interpersonal communication - have long been utilized by national family planning programs to create awareness about contraceptive methods, to shift social norms related to fertility control, and to promote specific behaviors, such as the use of condoms, injectable methods or permanent sterilization. However, demonstrating the effectiveness of these campaigns is often complicated because the infeasibility of experimental designs generally yields statistically non-equivalent samples of campaign-exposed and unexposed individuals.

Methods

Using data from a panel survey of reproductive age women in Egypt, we estimate the effects of the multimedia health communication campaign “Your Health, Your Wealth” (“Sahatek Sarwetek”) on precursors to contraceptive use (e.g., spousal communication, birth spacing attitudes) and on modern contraceptive use. Difference-in-differences and fixed effects estimators that exploit the panel nature of the data are employed to control for both observed and unobserved heterogeneity in the sample of women who self-report recall of the messages, thereby potentially improving upon methods that make no such controls or that rely solely on cross-sectional data.

Findings

All of the estimators find positive effects of the “Your Health, Your Wealth” campaign on reproductive health outcomes, though the magnitudes of those effects diverge, often considerably. Difference-in-differences estimators find that exposure to the campaign increases the likelihood of spousal discussions by 14.4 percentage points (pp.) (SE = .039, p<0.001) but has no effect on contraceptive use. In contrast, the fixed effects, instrumental variables estimator, controlling for unobserved heterogeneity, finds a large, statistically significant effect on modern contraceptive use (27.4 pp., SE = 0.135, p = 0.043).

Conclusions

The difficulties of evaluating family planning communication programs may be surmountable using panel data and analytic methods that address both observed and unobserved heterogeneity in exposure. Not controlling for such effects may lead to substantial underestimates of the effectiveness of such campaigns.  相似文献   

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Evidence from a variety of recording methods suggests that many areas of the brain are far more sparsely active than commonly thought. Here, we review experimental findings pointing to the existence of neurons which fire action potentials rarely or only to very specific stimuli. Because such neurons would be difficult to detect with the most common method of monitoring neural activity in vivoextracellular electrode recording—they could be referred to as “dark neurons,” in analogy to the astrophysical observation that much of the matter in the universe is undetectable, or dark. In addition to discussing the evidence for largely silent neurons, we review technical advances that will ultimately answer the question: how silent is the brain?  相似文献   

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The “Reading the Mind in the Eyes” test (Eyes test) is an advanced test of theory of mind. Typical sex difference has been reported (i.e., female advantage). Individuals with autism show more difficulty than do typically developing individuals, yet it remains unclear how this is modulated by sex, as females with autism have been under-represented. Here in a large, non-male-biased sample we test for the effects of sex, diagnosis, and their interaction. The Eyes test (revised version) was administered online to 395 adults with autism (178 males, 217 females) and 320 control adults (152 males, 168 females). Two-way ANOVA showed a significant sex-by-diagnosis interaction in total correct score (F(1,711) = 5.090, p = 0.024, ηp 2 = 0.007) arising from a significant sex difference between control males and females (p < 0.001, Cohen’s d = 0.47), and an absence of a sex difference between males and females with autism (p = 0.907, d = 0.01); significant case-control differences were observed across sexes, with effect sizes of d = 0.35 in males and d = 0.69 in females. Group-difference patterns fit with the extreme-male-brain (EMB) theory predictions. Eyes test-Empathy Quotient and Eyes test-Autism Spectrum Quotient correlations were significant only in females with autism (r = 0.35, r = -0.32, respectively), but not in the other 3 groups. Support vector machine (SVM) classification based on response pattern across all 36 items classified autism diagnosis with a relatively higher accuracy for females (72.2%) than males (65.8%). Nevertheless, an SVM model trained within one sex generalized equally well when applied to the other sex. Performance on the Eyes test is a sex-independent phenotypic characteristic of adults with autism, reflecting sex-common social difficulties, and provides support for the EMB theory predictions for both males and females. Performance of females with autism differed from same-sex controls more than did that of males with autism. Females with autism also showed stronger coherence between self-reported dispositional traits and Eyes test performance than all other groups.  相似文献   

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《Free radical research》2013,47(4-5):277-281
In the presence of excess hydrogen peroxide. human oxyhaemoglobin and oxyleghaemoglobin from soybean root nodules cause oxidation of dimethylsulphoxide to formaldehyde. This reaction is inhibited by thiourea but not by phenylalanine. HEPES. mannitol or arginine. It is concluded that dimethylsulphoxide oxidation is not mediated by “free” hydroxyl radicals. consistent with previous conclusions that intact haemoglobin, leghaemoglobin or myoglobin molecules do not react with H2O2 to form hydroxyl radicals detectable outside the protein.  相似文献   

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This article analyses the role of immigrant entrepreneurs’ class positions in understanding the participation of children in business activities. Immigrant entrepreneurship scholarship has highlighted how the participation of children depends on relations of reciprocity as well as on the lack of opportunities in paid employment. I argue that the (non) contribution of children has to do with the social mobility strategies that migrant families put in place. Drawing on the narratives of fifty-five Latin American entrepreneurs and family members in Spain, I explain (i) the role of the small firm in trajectories of social mobility, (ii) how class positions explain the (non) participation of children, and (iii) the mechanisms by which downward mobility is cushioned through practices of distinction for middle-class entrepreneurs. The article contributes to nuance our understanding of the role of family ties in migrant firms by integrating the impact of class on the lives of migrants’ children.  相似文献   

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Previous studies investigating attitudes to genetically modified (GM) foods suggest a correlation between negative attitudes and low levels of science education, both of which are associated with women. In a qualitative focus group study of Australian women with diverse levels of education, we found attitudes to GM foods were part of a complex process of making “good” food decisions, which included other factors such as locally produced, fresh/natural, healthy and nutritious, and convenient. Women involved in GM crop development and those with health science training differed in how they used evidence to categorize GM foods. Our findings contribute to a deeper understanding of how GM food, and the role of science and technology in food production and consumption more broadly, is understood and discussed amongst diverse “publics” and across different “sciences,” and to research related to deepening public engagement at the intersection of science and values.  相似文献   

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The human–animal bond is a relational theory which describes the dynamic between humans and nonhuman animals that satisfies needs in each for companionship and emotional support, framing companion animals as valued family members. Social workers have historically ignored the central role companion animals play in the lives of their clients, adopting an anthropocentric view underpinned by human rights and social justice. However, the need for companion animal-inclusive practice features in recent social work literature. As companion animals are intricately woven into the lives of their guardians, it follows that their inevitable death brings a profound sense of loss and thus an opportunity for social work intervention. The aim of this research was to see if there was a role for social work practitioners to support grieving animal companion guardians. Qualitative thematic analysis was performed on 218 candid online responses to an article on the topic of losing a companion animal, from which four major themes were identified: strength of the bond, anthropocentrically disenfranchised grief, anticipatory grief in the context of euthanasia, and the need for professional support. This analysis demonstrates the strength of the human– animal bond, illustrates how the dominant anthropocentric hegemony disenfranchises this variety of grief and loss, describes the experience of anticipatory grief in the context of euthanasia, and identifies the need for professional support. Implications for social work practice are identified, with opportunities for social workers to exchange their anthropocentric approach for a biocentric view, provide support to veterinarians and other professionals, and to work toward challenging the social constructs, which disenfranchise companion animal loss.  相似文献   

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Molecular mechanics and semiempirical calculations using HyperChem 5 were carried out to investigate whether the results obtained can explain why 2-hydroxypyridine is far more soluble in water than 3-hydroxypyridine. The results of molecular mechanics calculations show that in solution in water the total energy of 2-hydroxypyridine in the oxo form is less than that of 3-hydroxypyridine in the zwitterionic form by 2.14 kcal x mol(-1). The difference is much greater for the AM1 optimized H-bonded molecules. The greater amount of energy released in dissolution and H-bond formation by 2-hydroxypyridine than by 3-hydroxypyridine together with a higher crystal lattice energy for the latter provide an explanation as to why 3-hydroxypyridine is much less soluble in water than 2-hydroxypyridine. When the predicted electronic spectral lines of the compounds were compared with the observed lambda(max) values, it is found that generally the results obtained using AM1 agree more closely with the experimentally observed values.  相似文献   

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This is the first quantitative analysis of data from urine drug tests for compliance to treatment medications and abstinence from drug abuse across “levels of care” in six eastern states of America. Comprehensive Analysis of Reported Drugs (CARD) data was used in this post-hoc retrospective observational study from 10,570 patients, filtered to include a total of 2,919 patients prescribed at least one treatment medication during 2010 and 2011. The first and last urine samples (5,838 specimens) were analyzed; compliance to treatment medications and abstinence from drugs of abuse supported treatment effectiveness for many. Compared to non-compliant patients, compliant patients were marginally less likely to abuse opioids, cannabinoids, and ethanol during treatment although more likely to abuse benzodiazepines. Almost 17% of the non-abstinent patients used benzodiazepines, 15% used opiates, and 10% used cocaine during treatment. Compliance was significantly higher in residential than in the non-residential treatment facilities. Independent of level of care, 67.2% of the patients (n = 1963; P<.001) had every treatment medication found in both first and last urine specimens (compliance). In addition, 39.2% of the patients (n = 1143; P<.001) had no substance of abuse detected in either the first or last urine samples (abstinence). Moreover, in 2010, 16.9% of the patients (n = 57) were abstinent at first but not at last urine (deteriorating abstinence), the percentage dropped to 13.3% (n = 174) in 2011; this improvement over years was statistically significant. A longitudinal analysis for abstinence and compliance was studied in a randomized subset from 2011, (n = 511) representing 17.5% of the total cohort. A statistically significant upward trend (p = 2.353×10−8) of abstinence rates as well as a similar but stronger trend for compliance ((p = 2.200×10−16) was found. Being cognizant of the trend toward drug urine testing being linked to medical necessity eliminating abusive screening, the interpretation of these valuable results require further intensive investigation.  相似文献   

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The absence of spatial and temporal information in the data from a typical Life Cycle Inventory puts constraints on the possibilities of subsequent Life Cycle Impact Assessment to predict actual impact. Usual methods for Life Cycle Impact Assessment (often referred to as “less is better” methods) make only limited use of spatial and temporal information, because they predict concentration increases rather than full concentrations. As a consequence it does not seem possible to evaluate whether a threshold value is surpassed. The resulting poor accordance between the predicted impact and the expected occurrence of actual impact is a major problem. This problem is particularly relevant for human toxicity assessment, since the probability of surpassing thresholds here traditionally is the main point of attention. A considerable group of practitioners suggests to follow an “only above threshold” principle by introduction of assessment tools from risk assessment and environmental impact assessment in LCA. Intensive debate is going on about possibilities and limitations of “less is better” and “only above threshold”. The debate is obscured by two underlying discussions (about no-effect-levels and about data-availability) that are partly, but not fully intertwined. Both principles tend to be given fixed positions in these discussions, and are therefore often put forward as fundamentally different and incompatible with each other. This article entwines the discussions, shows parallels between both principles, and uses these parallels to present a new method for Life Cycle Impact Assessment of human toxicity from air emissions that — with limited data requirement from Life Cycle Inventory — can take as well threshold evaluation and spatial source-differentiation into account.  相似文献   

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Abstract I show that three parametric-bootstrap (PB) applications that have been proposed for phylogenetic analysis, can be misleading as currently implemented. First, I show that simulating a topology estimated from preliminary data in order to determine the sequence length that should allow the best tree obtained from more extensive data to be correct with a desired probability, delivers an accurate estimate of this length only in topological situations in which most preliminary trees are expected to be both correct and statistically significant, i.e. when no further analysis would be needed. Otherwise, one obtains strong underestimates of the length or similarly biased values for incorrect trees. Second, I show that PB-based topology tests that use as null hypothesis the most likely tree congruent with a pre-specified topological relationship alternative to the unconstrained most likely tree, and simulate this tree for P value estimation, produce excessive type I error (from 50% to 600% and higher) when they are applied to null data generated by star-shaped or dichotomous four-taxon topologies. Simulating the most likely star topology for P value estimation results instead in correct type-I-error production even when the null data are generated by a dichotomous topology. This is a strong indication that the star topology is the correct default null hypothesis for phylogenies. Third, I show that PB-estimated confidence intervals (CIs) for the length of a tree branch are generally accurate, although in some situations they can be strongly over- or under-estimated relative to the “true” CI. Attempts to identify a biased CI through a further round of simulations were unsuccessful. Tracing the origin and propagation of parameter estimate error through the CI estimation exercise, showed that the sparseness of site-patterns which are crucial to the estimation of pivotal parameters, can allow homoplasy to bias these estimates and ultimately the PB-based CI estimation. Concluding, I stress that statistical techniques that simulate models estimated from limited data need to be carefully calibrated, and I defend the point that pattern-sparseness assessment will be the next frontier in the statistical analysis of phylogenies, an effort that will require taking advantage of the merits of black-box maximum-likelihood approaches and of insights from intuitive, site-pattern-oriented approaches like parsimony.  相似文献   

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Refugee men face unique mental health stressors in the pre- and post-migratory periods. However, there has been little in-depth research on the mental health of refugee men in Canada. Given this situation, the overall aim of this study is to explore the psycho-social experience of Sri Lankan Tamil refugee men in Canada. Particular objectives include better understanding any inter-relationship between war-trauma, migration, concepts of masculinity and mental health. The study employed a two-phase participatory action research design based on the grounded theory approach. Phase 1 involved an 8-month ethnography conducted in Sri Lanka. Phase 2 consisted of qualitative interviews with 33 Sri Lankan Tamil refugee men living in Canada. Consistent with grounded theory, analysis was conducted inductively and iteratively. Four specific themes emerged from the data (i) gendered helplessness of war: participants commonly reported ongoing negative rumination regarding experiences where they were unable to adequately protect loved ones from physical suffering or death; (ii) reduced capacity: participants frequently felt unable to fulfill culturally sanctioned duties, such as supporting their family, due to ongoing pre- and post-migratory stress; (iii) redundancy: many participants felt that they were useless in Canada, as they could not fulfill typical masculine social roles (e.g. provider) due to factors such as unemployment and underemployment; (iv) intimate criticism: some participants reported that their spouses would often attempt to ‘shame’ them into greater achievement by constantly reminding them of their ‘failures’. Many found this distressing. These various failures culminated in a state that we label “depleted masculinity”, which participants linked to emotional and behavioural problems. Participants reported that they actively tried to rebuild their masculine identity, for example by adopting leadership roles in community organizations, which fostered resiliency. Results suggest a need to review and rebuild masculine identity to support the mental health of refugee men.  相似文献   

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Consent processes have attracted significant research attention over the last decade, including in the global south. Although relevant studies suggest consent is a complex negotiated process involving multiple actors, most guidelines assume consent is a one-off encounter with a clear ‘yes’ or ‘no’ decision. In this paper we explore the concept of ‘silent refusals’, a situation where it is not clear whether potential participants want to join studies or those in studies want to withdraw from research, as they were not actively saying no. We draw on participant observation, in-depth interviews and group discussions conducted with a range of stakeholders in two large community based studies conducted by the KEMRI Wellcome Trust programme in coastal Kenya. We identified three broad inter-related rationales for silent refusals: 1) a strategy to avoid conflicts and safeguard relations within households, - for young women in particular—to appear to conform to the wishes of elders; 2) an approach to maintain friendly, appreciative and reciprocal relationships with fieldworkers, and the broader research programme; and 3) an effort to retain study benefits, either for individuals, whole households or wider communities. That refusals and underlying rationales were silent posed multiple dilemmas for fieldworkers, who are increasingly recognised to play a key interface role between researchers and communities in many settings. Silent refusals reflect and reinforce complex power relations embedded in decisions about research participation, with important implications for consent processes and broader research ethics practice. Fieldworkers need support to reflect upon and respond to the ethically charged environment they work in.  相似文献   

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Recently, we proposed a new mechanism for understanding the Warburg effect in cancer metabolism. In this new paradigm, cancer-associated fibroblasts undergo aerobic glycolysis, and extrude lactate to “feed” adjacent cancer cells, which then drives mitochondrial biogenesis and oxidative mitochondrial metabolism in cancer cells. Thus, there is vectorial transport of energy-rich substrates from the fibroblastic tumor stroma to anabolic cancer cells. A prediction of this hypothesis is that cancer-associated fibroblasts should express MCT4, a mono-carboxylate transporter that has been implicated in lactate efflux from glycolytic muscle fibers and astrocytes in the brain. To address this issue, we co-cultured MCF7 breast cancer cells with normal fibroblasts. Interestingly, our results directly show that breast cancer cells specifically induce the expression of MCT4 in cancer-associated fibroblasts; MCF7 cells alone and fibroblasts alone, both failed to express MCT4. We also show that the expression of MCT4 in cancer-associated fibroblasts is due to oxidative stress, and can be prevented by pre-treatment with the anti-oxidant N-acetyl-cysteine. In contrast to our results with MCT4, we see that MCT1, a transporter involved in lactate uptake, is specifically upregulated in MCF7 breast cancer cells when co-cultured with fibroblasts. Virtually identical results were also obtained with primary human breast cancer samples. In human breast cancers, MCT4 selectively labels the tumor stroma, e.g., the cancer-associated fibroblast compartment. Conversely, MCT1 was selectively expressed in the epithelial cancer cells within the same tumors. Functionally, we show that overexpression of MCT4 in fibroblasts protects both MCF7 cancer cells and fibroblasts against cell death, under co-culture conditions. Thus, we provide the first evidence for the existence of a stromal-epithelial lactate shuttle in human tumors, analogous to the lactate shuttles that are essential for the normal physiological function of muscle tissue and brain. These data are consistent with the “reverse Warburg effect,” which states that cancer-associated fibroblasts undergo aerobic glycolysis, thereby producing lactate, which is utilized as a metabolic substrate by adjacent cancer cells. In this model, “energy transfer” or “metabolic-coupling” between the tumor stroma and epithelial cancer cells “fuels” tumor growth and metastasis, via oxidative mitochondrial metabolism in anabolic cancer cells. Most importantly, our current findings provide a new rationale and novel strategy for anti-cancer therapies, by employing MCT inhibitors.Key words: caveolin-1, oxidative stress, pseudohypoxia, lactate shuttle, MCT1, MCT4, metabolic coupling, tumor stroma, predictive biomarker, SLC16A1, SLC16A3, monocarboxylic acid transporter  相似文献   

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