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1.
Fluid-structural coupling occurs when microcantilever sensors vibrate in a fluid. Due to the complexity of the mechanical characteristics of microcantilevers and lack of high-precision microscopic mechanical testing instruments, effective methods for studying the fluid-structural coupling of microcantilevers are lacking, especially for non-rectangular microcantilevers. Here, we report fluid-structure interactions (FSI) of the cable-membrane structure via a macroscopic study. The simplified aeroelastic model was introduced into the microscopic field to establish a fluid-structure coupling vibration model for microcantilever sensors. We used the finite element method to solve the coupled FSI system. Based on the simplified aeroelastic model, simulation analysis of the effects of the air environment on the vibration of the commonly used rectangular microcantilever was also performed. The obtained results are consistent with the literature. The proposed model can also be applied to the auxiliary design of rectangular and non-rectangular sensors used in fluid environments.  相似文献   
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Waterlogging is one of the major stresses limiting crop production worldwide. The understanding of the mechanisms of plant adaptations to waterlogging stress helps improve plant tolerance to stress. In this study, physiological responses and morpho-anatomical adaptations of seven different barley genotypes were investigated under waterlogging stress. The results showed that the waterlogging-tolerant varieties (TX9425, Yerong, TF58) showed less reduction in plant height, SPAD (soil–plant analyses development analyses) value, tillers, shoot and root biomasses than did the waterlogging-sensitive varieties (Franklin, Naso Nijo, TF57). Under waterlogging stress condition, the tolerant genotypes also showed a much larger number of adventitious roots than did the sensitive genotypes. More intercellular spaces and better integrated chloroplast membrane structures were observed in the leaves of the waterlogging-tolerant cultivars, which is likely due to increased ethylene content, decreased ABA content and less accumulation of O2.?. The ability to form new adventitious roots and intercellular spaces in shoots can also be used as selection criteria in breeding barley for waterlogging tolerance.  相似文献   
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In this paper, the panel count data analysis for recurrent events is considered. Such analysis is useful for studying tumor or infection recurrences in both clinical trial and observational studies. A bivariate Gaussian Cox process model is proposed to jointly model the observation process and the recurrent event process. Bayesian nonparametric inference is proposed for simultaneously estimating regression parameters, bivariate frailty effects, and baseline intensity functions. Inference is done through Markov chain Monte Carlo, with fully developed computational techniques. Predictive inference is also discussed under the Bayesian setting. The proposed method is shown to be efficient via simulation studies. A clinical trial dataset on skin cancer patients is analyzed to illustrate the proposed approach.  相似文献   
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To report the results of a systematic review and meta-analysis examining whether weight loss interventions improve body image in obese/overweight individuals. Medline, Current Contents, and the Cochrane database were searched to identify studies involving obese/overweight adults who were enrolled in weight loss interventions in which body image was quantitatively assessed. Outcomes assessed were changes in body shape concern, body size dissatisfaction, and body satisfaction (intervention vs comparator/control group). Seven studies were included in the systematic review (4 in the meta-analysis). All but 1 study involved female participants only. The type of weight loss intervention varied between studies as did the type of control/comparator group. In 3 studies, there was no significant difference in body image outcomes, whereas in 4 studies, improvement in body image was significantly more pronounced in the intervention vs the control/comparator group. Meta-analysis revealed that improvements in body shape concern (standardized difference: -0.52; 95% confidence interval [CI]: -1.04 to 0.00), body size dissatisfaction (standardized difference: -0.66; 95% CI: -0.88 to -0.45), and body satisfaction (standardized difference: 0.74; 95% CI: 0.09 to 1.38) significantly favored the intervention over the comparator/control group (P<0.05). The results of this systematic review/meta-analysis lend support to the notion that weight loss interventions may improve body image. This is a noteworthy finding that has clear clinical applicability because body image affects psychological well-being and the ability of an individual to maintain weight loss. Future research should determine which weigh loss interventions are associated with optimal improvements in body image and maintenance of weight loss.  相似文献   
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Biomechanics and Modeling in Mechanobiology - It is well known that residual deformations/stresses alter the mechanical behavior of arteries, e.g., the pressure–diameter curves. In an effort...  相似文献   
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