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71.
Adolescent males and females differ in their responses to social threat. Yet, threat processing is often probed in non-social contexts using the error-related negativity (ERN; Flanker EEG Task), which does not yield sex-specific outcomes. fMRI studies show inconsistent patterns of sex-specific neural engagement during threat processing. Thus, the relation between threat processing in non-social and social contexts across sexes and the effects perceived level of threat on brain function are unclear. We tested the interactive effect of non-social threat-vigilance (ERN), sex (N = 69; Male=34; 11–14-year-olds), and perceived social threat on brain function while anticipating feedback from ‘unpredictable’, ‘nice’, or ‘mean’ purported peers (fMRI; Virtual School Paradigm). Whole-brain analyses revealed differential engagement of precentral and inferior frontal gyri, putamen, anterior cingulate cortex, and insula. Among males with more threat-vigilant ERNs, greater social threat was associated with increased activation when anticipating unpredictable feedback. Region of interest analyses revealed this same relation in females in the amygdala and anterior hippocampus when anticipating mean feedback. Thus, non-social threat vigilance relates to neural engagement depending on perceived social threat, but peer-based social contexts and brain regions engaged, differ across sexes. This may partially explain divergent psychosocial outcomes in adolescence.  相似文献   
72.
ObjectiveTo describe the different perceptions about health rights for migrant population in Chile published on Twitter, concerning the first liver transplant carried out in Chile to a foreign national woman from Haiti, in September 2018.MethodQualitative study, case analysis. The case corresponded to the first emergency liver transplant in a migrant woman in Chile. Opinions expressed on Twitter regarding this case were collected between September 29 and November 17 (n = 339). Thematic analysis was performed using NVivo12 software, with codes defined conforming to the objective.ResultsAccording to the perceptions raised on Twitter, the right to access health services of the migrant population in Chile should be limited, and priority should be given to nationals. These opinions coexist with viewing health as a human right. There are also feelings of racism and discrimination towards this group.ConclusionsIn Chile, there are different perceptions of what should grant rights of access to migrant health services. This situation can generate a worsening of stigmatization and vulnerability faced by migrants and a barrier to the policy's implementation, further exacerbating the presence of health inequities.  相似文献   
73.
Most engineering structures are composed of basic components such as plates, shells, and beams, and their dynamic characteristics under explosion load determine the impact resistance of the structure. In this paper, a three-dimensional composite steel structure was designed using a beam, plate, and other basic elements to study its mechanical behavior under explosion load. Subsequently, experiments on the composite steel structure under explosion load were carried out to study its mechanical behavior, and the failure mode and deformation data of the composite steel structure were obtained, which provided important experimental data regarding the dynamic response and mechanical behavior of the composite steel structure under explosion load. Then, we independently developed a parallel program with the coupled calculation method to solve the numerical simulation of the dynamic response and failure process of the composite steel structure under explosion load. This program adopts the Euler method as a whole, and Lagrange particles are used for materials that need to be accurately tracked. The numerical calculation results are in good agreement with the experimental data, indicating that the developed parallel program can effectively deal with the large deformation problems of multi-medium materials and the numerical simulation of the complex engineering structure failures subjected to the strong impact load.  相似文献   
74.

Aims

To investigate the 29-year (1985–2014) trends in body dimensions and physical fitness test performances among 12-year-old Chinese children living in urban and rural areas.

Methods

The data were from the findings of seven cross-sectional surveys from the Chinese National Survey on Students’ Constitution and Health. In the seven surveys, there were 34,238; 11,664; 17,485; 18,057; 19,254; 17,962; and 17,906 children, respectively. Anthropometric measurements and physical fitness performances of 12-year-old Chinese children living in rural and urban areas were analyzed. Polynomial models were used to analyze trends in test performances. Analysis of variance was used to assess the urban–rural differentials.

Results

The height and weight of both urban and rural children substantially increased from 1985 to 2014. Urban children were taller and heavier than rural children. A slight narrowing of the urban–rural differential in height was observed. The disparity in weight increased from 1985 to 2000 and decreased thereafter. Urban children performed better in most of the physical fitness tests examined, such as standing long jump, 50-m run, and sit-ups. The urban–rural disparity decreased from 1985 to 2014 in 50-m run, standing long jump, and sit-up score; the largest difference in 10?×?50 m run and pull-up score was observed in 2000 and 2005, respectively.

Conclusions

There was a general decline in physical fitness in both urban and rural children after 2000. Urgent, targeted actions need to be taken by public health policy officials and parents to maintain or improve the physical fitness of children.  相似文献   
75.

Objective

To explore from a gender perspective the association with subjective health of the interaction between education and household arrangements within the framework of social determinants of health placed at the micro and mezzo levels.

Methods

The data comes from the Spanish sample of the European Union Statistics on Income and Living Conditions for 2014. Independent logistic regression models for men and women were run to analyze the association with subjective health of the interaction between education and household arrangements. An additive model was run to assess possible advantages over the interaction approach.

Results

The interaction models show a lower or even no significant effect on health of household arrangements usually negatively associated with health among individuals with high education, displaying specific patterns according to sex.

Conclusions

Health profiles of women and men are more precisely drawn if both social determinants of health are combined. Among the women, the important role was confirmed of both social determinants of health in understanding their health inequalities. Among the men, mainly those with low educational achievement, the interaction revealed that the household was a more meaningful social determinant of health. This could enable the definition of more efficient public policies to reduce health and gender inequalities.  相似文献   
76.
The Polish dietary supplement market is growing steadily. However, even though these products may have an impact on health they are not as strongly regulated as pharmaceuticals. In 2016/17 the introduction of new regulations covering the marketing of dietary supplements in Poland was proposed. This article briefly describes the Polish market for dietary supplements and assesses the benefits and risks associated with its development. A range of potential legislative changes, such as a total ban on dietary supplements, a ban on using the images and recommendations of authoritative entities, increased fines for breaking the law, and other measures are under consideration. We describe the advantages (e.g., better customer protection, and the limitation of inappropriate, misleading advertising) and disadvantages (e.g., a decrease in product innovation, deterioration in product offerings, and rises in product prices) of the proposed changes. As a European Union member, Poland adopts EU law, but EU directives have only harmonized some issues relating to dietary supplement marketing, other key aspects remaining within the competence of member states, but it is noted that some proposed changes in Polish law (e.g., an advertising ban) are so strict that they are unlikely to be acceptable to the EU.  相似文献   
77.
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79.
《The Journal of arthroplasty》2022,37(11):2272-2281
BackgroundEarly total knee arthroplasty failures continue to surface in the literature. Cementation technique and implant design are two of the most important scenarios that can affect implant survivorship. Our objectives were to develop a more suitable preclinical test to evaluate the endurance of the implant-cement-bone interface under anterior shear and internal-external (I/E) torsional shear testing condition in a biomechanical sawbones.MethodsImplants tested included the AS VEGA System PS and the AS Columbus CR/PS (Aesculap AG, Germany), with zirconium nitride (ZrN) coating. Tibial implants were evaluated under anterior shear and I/E torsional shear conditions with 6 samples in 4 test groups. For the evaluation of the I/E torsional shear endurance behavior, a test setup was created allowing for clinically relevant I/E rotation with simultaneous high axial/tibio-femoral load. The test was performed with an I/E displacement of ±17.2°, for 1 million cycles with an axial preload of 3,000 N.ResultsAfter the anterior shear test an implant-cement-bone fixation strength for the AS VEGA System tibial tray of 2,674 ± 754 N and for the AS Columbus CR/PS tibial tray of 2,177 ± 429 N was determined (P = .191). After I/E rotational shear testing an implant-cement-bone fixation strength for the AS VEGA System PS tray of 2,561 ± 519 N and for the AS Columbus CR/PS tray of 2,824 ± 515 N was resulted (P = .39).ConclusionBoth methods had varying degrees of failure modes from debonding to failure of the sawbones foam. These two intense biomechanical loading tests are more strenuous and more representative of clinical activity.  相似文献   
80.
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