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931.
In this article, we attempt to conceptualize the historical development and the governance structure of the transnational organic cotton network from Benin. We aim to discover how the organic cotton production‐consumption network is governed locally and internationally. Existing bodies of literature on international agricultural production networks, in particular the Global Value Chains (GVC) perspective, focus on economic dimensions, but find it difficult to incorporate the sustainability dimension. We favour widening the concept of GVCs beyond economics by acknowledging and including environmental rationalities and the representatives of their interests, not as external elements, but rather as co‐governing or co‐structuring factors (or actors) of sustainable value chains. Our findings reveal that beyond the traditional producer versus buyer dualism, intermediate stakeholders, namely transnational and local environmental NGO networks, are instrumental in the construction, maintenance and transformation of the organic cotton network. It is also apparent that farmers' leaders play an important role in mediating and (re)building trust among organic farmers, though they exert insufficient vertical power in the organic cotton network to control it.  相似文献   
932.
933.
Non-hormonal approaches to premenstrual syndrome (PMS) treatment such as selective serotonin reuptake inhibitors are by no means effective for all women and frequently we must resort to endocrine therapy. During many of the hormonal approaches, PMS-like symptoms can be introduced or re-introduced during the necessary cyclical or continuous progestogen component of the therapy. This is seen with combined oral contraception, progestogen only contraception, progestogen therapy for heavy menstrual bleeding and endometriosis, sequential hormone replacement therapy and any therapeutic strategy for premenstrual syndrome where it is necessary to provide endometrial protection, including estrogen suppression of ovulation or add-back during gonadotrophin releasing hormone suppression. The link to progestogen is very often missed by health professionals. When the pattern of symptoms mimics the cyclicity of PMS, it is termed progestogen-induced premenstrual disorder. The need to use progestogen to protect the endometrium from the proliferative actions of estrogen can pose insurmountable difficulties in managing premenstrual disorders. In the absence of any really useful evidence, nearly all practice in this area depends on clinician experience. We cannot afford to wait for adequate research evidence to be produced - it never will - and so we must rely on empirical findings, clinical experience, theoretical strategies and common sense.  相似文献   
934.
Using behavioral self-regulation processes may facilitate exercise among older women with heart disease. Data from women in a heart disease-management program (n = 658, mean 73 years), was used to explore associations among exercise self-regulation components (i.e., choosing to improve exercise and observing, judging, and reacting to one's behavior) and exercise capacity. General linear models showed that choosing exercise predicted higher exercise self-regulation scores postprogram and 8 months later. In turn, these scores predicted greater improvements in exercise capacity concurrently and 8 months later. Interaction analyses revealed that the effect of self-regulation on exercise capacity was stronger among women who chose to work on exercise.  相似文献   
935.
We test whether job insecurity of parents and children affect children’s moving-out decisions. Macroeconomic estimates for 13 European countries over 1983–2004 show that coresidence increases by 1.7 percentage points (PP) following a 10 PP rise in the share of youths perceiving their job to be insecure and declines by 1.1 PP following the same increment in insecurity for older workers. Microeconometric evidence for Italy in the mid-1990s shows that the probability of moving out increases by about half a percentage point for a one-standard-deviation increase in paternal insecurity and by one-third of a percentage point for a one-standard-deviation decrease in children’s insecurity.  相似文献   
936.
The fifth revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) is scheduled for publication in 2013. It will include several changes to the diagnosis of pathological gambling: the name of the disorder will be altered, the threshold for diagnosis will decrease, and one criterion will be removed. This paper reviews the rationale for these changes and addresses how they may impact diagnosis and treatment of the disorder, as well as potential for future research in the field.  相似文献   
937.
This study proposes theoretical and practical frameworks to systematically examine mediated public relations in social media spaces. We applied a social network conceptual framework to identify and characterize social mediators that connect the US State Department with its international public. The results showed that social mediators vary in terms of their formality and interdependence. Formal social mediators were primarily US government agencies while informal social mediators were nongovernmental organizations (NGOs) and individuals. Notably, relationships with populations in the Middle East and North Africa were mediated primarily by informal actors, and formal mediators played a key role in connecting the public with everywhere else in the world. Government-related formal mediators and informal social mediators showed similar levels of bilateral relationships. In contrast, news media, the most traditional public relations mediators, were rarely found as social mediators and demonstrated the most unilateral relationships.  相似文献   
938.
The current research examined whether the presentation of gambling-related cues facilitates the activation of gambling outcome expectancies using both reaction time (RT) and self-report modes of assessment. Gambling outcome expectancies were assessed by having regular casino or online gamblers (N = 58) complete an outcome expectancy RT task, as well as a self-report measure of gambling outcome expectancies, both before and after exposure to one of two randomly assigned cue conditions (i.e., casino or control video). Consistent with hypotheses, participants exposed to gambling-related cues (i.e., casino cue video condition) responded faster to positive outcome expectancy words preceded by gambling prime relative to non-gambling prime pictures on the post-cue RT task. Similarly, participants in the casino cue video condition self-reported significantly stronger positive gambling outcome expectancies than those in the control cue video condition following cue exposure. Activation of negative gambling outcome expectancies was not observed on either the RT task or self-report measure. The results indicate that exposure to gambling cues activates both implicit and explicit positive gambling outcome expectancies among regular gamblers.  相似文献   
939.
940.
Pollen specialization by solitary bees in an urban landscape   总被引:1,自引:1,他引:0  
Many polylectic bee species are known to specialize locally on one or a few pollen types to increase foraging efficiency. What is relatively unknown is how different landscapes influence foraging decisions, and whether habitat alteration, such as that resulting from urbanization, influences broad-scale foraging activities of bees. This study evaluates the type and diversity of pollen collected by two solitary bees that are common in Toronto, Ontario, Canada, the native Osmia pumila and the exotic O. caerulescens, sampled in trap nests set up in urban parks and gardens. We found that the dominant pollen in every successful brood cell was either of one widespread, cosmopolitan lawn-invasive plant species (Trifolium repens) or one of two wind-pollinated tree genera (Quercus spp. and Betula spp.). In combination, these three represented more than 90 % of all pollen collected by each bee species. Despite considerable overlap in the dominant pollen types collected by each bee species, the exotic O. caerulescens was significantly more specialized than the native O. pumila. Brood cells with Betula as the dominant pollen type were more pollen species-rich than those cells having Trifolium or Quercus as dominant, perhaps a result of the comparatively low protein content in Betula pollen.  相似文献   
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