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101.
Theory suggests that by strengthening collective efficacy among neighbors, neighborhoods can more effectively engage in collective action. The research linking the two components of collective efficacy–social cohesion and social control–with collective action is limited. This study uses structural equation modeling with a nationally representative sample from the United States Census Bureau's American Housing Survey (N = 22,106) to analyze these relationships. This analysis finds that neither component of collective efficacy is directly associated with collective action. Instead, social cohesion is negatively, directly associated with civic engagement, social control is positively directly associated with civic engagement, and civic engagement is positively associated with collective action. Social cohesion and social control are indirectly associated with collective action when including civic engagement. Understanding the associations between collective efficacy, civic engagement, and collective action is informative for understanding effective and efficient community participation to facilitate change.  相似文献   
102.
The aim of this study was to investigate the role of the nitric oxide (NO) system in ovarian function, by determining if arginine (Arg) supplementation impacts follicle number, cell proliferation, and expression of the NO system members in nutritionally compromised ewes. Ewes were randomly assigned into maintenance (C, 100% requirements), excess (O; 2xC), or restricted (U; 0.6xC) diets 8 weeks prior to Arg treatment. Ewes were individually fed twice daily with pelleted diets. Ewes from each nutritional group were randomly assigned to one of two treatments: saline or Arg, which was initiated on day 0 of the estrous cycle and administered 3 times per day. Ovaries were collected at the early-luteal, mid-luteal and late-luteal/follicular phases of the estrous cycle to determine 1) the number of surface follicles, 2) follicle cell proliferation marked by Ki67 protein expression, and 3) expression of endothelial nitric oxide (eNOS; NOS3) and soluble guanylyl cyclase beta (sGC; GUCY1B3) protein and mRNA in granulosa (G) and theca (T) layers using immunohistochemistry followed by image analysis and qPCR, respectively. During nutritional treatment, C maintained body weight, O gained 6±1.2 kg, and U lost 14±1.3 kg. Our data show that: 1) Ki67 was expressed in all ovarian compartments, eNOS protein was detected in blood vessels of T and stroma, and sGC protein was detected in T cells, and blood vessels of T layer and other ovarian compartments; 2) plane of nutrition affected the number of surface follicles, and thus folliculogenesis, cell proliferation in the T layer, eNOS and sGC protein expression in T, and NOS3 and GUCY1B3 mRNA expression in G; 3) Arg treatment affected cell proliferation in G and T, eNOS and sGC protein expression in T, mRNA expression of NOS3 in T in all groups, and GUCY1B3 in G depending on the stage of the estrous cycle; and 4) G and T cell proliferation, and expression of eNOS and sGC protein in T was affected by the stage of the estrous cycle. Our data demonstrated that plane of nutrition and Arg are involved in the regulation of follicular functions in non-pregnant sheep.  相似文献   
103.
EEG power analysis is firmly established in the cognitive domain. This contrasts with emotional stimulus processing, which thus far has yielded a complex and ambiguous pattern of findings. To further advance understanding, the present study examined emotional stimulus processing in the context of task variations and baseline activity, which included several manipulation checks as well as internal replication of findings across conditions. Participants (N = 16) viewed erotic and romantic pictures, differing in stimulus arousal. Pictures were presented briefly (120 ms), and intertrial interval was systematically varied (~1 vs. ~8 s). In one condition, participants passively viewed the pictures, in the other, they performed an active picture categorization task. The processing of erotic compared to romantic images was associated with a decrease in power in the alpha and lower beta band in posterior and anterior sensor clusters between 600–1,000 ms poststimulus. The finding was robust and confirmed across conditions, different quantifications, and independent from baseline activity. Furthermore, key findings regarding explicit task effects as well as ERPs sensitive to emotional arousal were replicated. Results are discussed with respect to the hypothesis that alpha‐ and lower beta‐band activity may reflect cortical activation associated with emotional stimulus significance.  相似文献   
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In recent years the role of the mammalian target of rapamycin (mTOR) pathway has emerged as crucial for normal cortical development. Therefore, it is not surprising that aberrant activation of mTOR is associated with developmental malformations and epileptogenesis. A broad spectrum of malformations of cortical development, such as focal cortical dysplasia (FCD) and tuberous sclerosis complex (TSC), have been linked to either germline or somatic mutations in mTOR pathway‐related genes, commonly summarised under the umbrella term ‘mTORopathies’. However, there are still a number of unanswered questions regarding the involvement of mTOR in the pathophysiology of these abnormalities. Therefore, a monogenetic disease, such as TSC, can be more easily applied as a model to study the mechanisms of epileptogenesis and identify potential new targets of therapy. Developmental neuropathology and genetics demonstrate that FCD IIb and hemimegalencephaly are the same diseases. Constitutive activation of mTOR signalling represents a shared pathogenic mechanism in a group of developmental malformations that have histopathological and clinical features in common, such as epilepsy, autism and other comorbidities. We seek to understand the effect of mTOR dysregulation in a developing cortex with the propensity to generate seizures as well as the aftermath of the surrounding environment, including the white matter.  相似文献   
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Studies aimed at repurposing existing drugs revealed that some antimalarial compounds possess anti-Zika virus (anti-ZIKV) activity. Here, we further tested 14 additional antimalarial drugs and their metabolites or analogs for anti-ZIKV activity using a phenotypic screening approach. We identified four compounds with varying anti-ZIKV activity, including a metabolite of amodiaquine termed desethylamodiaquine (DAQ) and N-desethylchloroquine (DECQ), a metabolite of chloroquine, which both exhibited low micromolar effective concentrations against three different ZIKV strains. Two other compounds termed dihydroartemisinin (DHA) and quinidine (QD) exhibited only partial inhibition of ZIKV replication. Characterization of the inhibitory mechanisms of DAQ and DECQ showed that both drugs target the entry step as well as postentry events of the viral replication cycle. These hits represent attractive starting points for future optimization of new anti-ZIKV drug candidates derived from antimalarial drugs and their analogs.  相似文献   
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