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Abstract Background An inverse relationship between physical activity (PA) and depression among adolescents has been reported in developed communities without consideration of sedentary behaviors (SB, including sitting for course study, viewing TV, and sleeping). We explored the association between recreational PA time (hr/wk) and depression after adjustment with SB and other possible confounders among Chinese adolescents. Methods A population-based cross-sectional study was conducted in Nanjing municipality of China in 2004 using a multi-stage cluster sampling approach. A total of 72 classes were randomly selected from 24 urban junior high schools and all students completed the structured questionnaire. Adolescent depression was examined by the Children's Depression Inventory (CDI) of Chinese version with cutoff point value of 20 or above as the presence of depression. Recreational PA time was measured by a question on weekly hours of PA outside of school. Descriptive statistics, multivariate logistic and linear regression models were used in analysis. Results The overall prevalence of depression was 15.7% (95%CI: 14.3%, 17.1%) among 2,444 eligible participants. It was found that physical activity was negatively associated with depression. After adjustment for sedentary behaviors and other potential confounders, participants who spent 1–7 hr/wk, 8–14 hr/wk and 15+ hr/wk for recreational PA, respectively, had odds ratios of 0.70 (95% CI = 0.57, 0.86), 0.68 (95% CI = 0.53, 0.88) and 0.66 (95% CI = 0.50, 0.87) for likelihood of being depressive, compared to their counterparts who spent 0–0.9 hr/wk for PA. This inverse relationship between PA time and depression remained statistically significant by gender and grade. Conclusion This study, conducted among Chinese adolescents, strengthened the evidence that physical activity was inversely associated with depression. Our study has important implications for health officers and public health professionals to pay much attention to the relationship between physical activity and depression in Mainland China.

Purpose: The purpose of this study is to evaluate the potential advantages of thoracoscopic versus open resection for symptomatic congenital pulmonary airway malformation (CPAM) in neonates.Methods: A retrospective review of the medical records of neonates (age ≤ 28 days) who underwent surgery for symptomatic CPAM from 2010 to 2020.Results: Of the 24 patients, 14 patients underwent thoracoscopic resection and 10 patients underwent open resection. 4 patients with CPAM located in the upper or middle lobes underwent lobectomy, and 20 underwent lung-preserving wedge resection in the lower lobe. Between the two groups, there were no statistically significant differences in related preoperative variables, including gestational age at birth, body weight, head circumference, lesion size, cystic adenomatoid malformation volume ratio (CVR), and age at operation (P > .05). The differences in intraoperative variables were statistically significant. The length of the surgical incision was significantly shorter in thoracoscopic resection group than in open resection group (1.4 cm [1.3-1.8] vs. 6.0 cm [5.0-8.0], P = .000), along with significantly less operative blood loss (3 ml [1-6] vs. 5 ml [2-10], P = .030) but significantly longer operation time (159 min [100-220] vs. 110 min [70-170], P = .003). Regarding postoperative variables, ventilator days, duration of chest tube use and length of hospital stay were not statistically significant (P > .05).Conclusion: Both thoracoscopic and open resection for symptomatic CPAM achieve good clinical outcomes, even in neonates. Thoracoscopic resection has minimal aesthetic effects and does not increase the risk of surgical or postoperative complications. Lung-preserving resection may be feasible for neonatal CPAM surgery. [ABSTRACT FROM AUTHOR]

This paper addresses the three concepts of consistency, stability and convergence in the context of compact finite volume schemes for systems of nonlinear hyperbolic conservation laws. The treatment utilizes the framework of ''balance laws''. Such laws express the relevant physical conservation laws in the presence of discontinuities. Finite volume approximations employ this viewpoint, and the present paper can be regarded as being in this category. It is first shown that under very mild conditions a weak solution is indeed a solution to the balance law. The schemes considered here allow the computation of several quantities per mesh cell (e.g., slopes) and the notion of consistency must be extended to this framework. Then a suitable convergence theorem is established, generalizing the classical convergence theorem of Lax and Wendroff. Finally, the limit functions are shown to be entropy solutions by using a notion of ''Godunov compatibility'', which serves as a substitute to the entropy condition. [ABSTRACT FROM AUTHOR]

This paper aims to reassess the Riemann solver for compressible fluid flows in Lagrangian frame from the viewpoint of modified equation approach and provides a theoretical insight into dissipation mechanism. It is observed that numerical dissipation vanishes uniformly for the Godunov-type schemes in the sense that associated dissipation matrix has zero determinant if an exact or approximate Riemann solver is used to construct numerical fluxes in the Lagrangian frame. This fact connects to some numerical defects such as the wall-heating phenomenon and start-up errors. To cure these numerical defects, a traditional numerical viscosity is added, as well as the artificial heat conduction is introduced via a simple passage of the Lax-Friedrichs type discretization of internal energy. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, a fully discrete high-resolution arbitrary Lagrangian-Eulerian (ALE) method is developed over untwisted time-space control volumes. In the framework of the finite volume method, 2D Euler equations are discretized over untwisted moving control volumes, and the resulting numerical flux is computed using the generalized Riemann problem solver. Then, the fluid flows between meshes at two successive time steps can be updated without a remapping process in the classic ALE method. This remapping-free ALE method directly couples the mesh motion into a physical variable update to reflect the temporal evolution in the whole process. An untwisted moving mesh is generated in terms of the vorticity-free part of the fluid velocity according to the Helmholtz theorem. Some typical numerical tests show the competitive performance of the current method. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ObjectiveEpidemiological studies have examined associations between dietary patterns and the risk of type 2 diabetes. However, information on dietary patterns and the risk of type 2 diabetes in Chinese populations is scarce. The aim of the present study was to identify dietary patterns and examine their association with incident hyperglycaemia in Nanjing, China.DesignA community-based prospective cohort study. Dietary assessment was carried out using a validated eighty-seven-item FFQ. Dietary patterns were identified by exploratory factor analysis. Participants were categorized into tertiles of dietary factor score for each dietary pattern. The relationship between dietary patterns and hyperglycaemia risk was analysed using multivariable linear and Cox regression.SettingSeven communities from two urban districts in Nanjing, China.SubjectsA total of 2900 of Chinese local residents aged 30 years or above, free of hyperglycaemia and other serious diseases, who participated in the baseline survey from June to September 2007 were followed up 3 years later from June to September 2010 for the development of hyperglycaemia. Fasting blood samples were collected at both baseline and 3-year follow-up surveys. Hyperglycaemia was defined as fasting plasma glucose concentration of ≥6·1 mmol/l or already taking oral hyperglycaemia agents for treatment of type 2 diabetes.ResultsFive major dietary patterns were identified: (i) the ‘condiments’ pattern; (ii) the ‘animal and plant protein’ pattern; (iii) the ‘healthy traditional’ pattern; (iv) the ‘fruits, eggs and juice’ pattern; and (v) the ‘alcohol, milk and tea’ pattern. A total of 2093 (72·2 %) individuals completed the follow-up survey and the 3-year cumulative incidence of hyperglycaemia was 7·5 % (158/2093). A 1-unit increase in the score for the ‘healthy traditional’ pattern was associated with a decrease of 0·054 mmol/l in fasting plasma glucose (P=0·017), while a 1-unit increase in the ‘fruits, eggs and juice’ pattern score was associated with an increase of 0·050 mmol/l in fasting plasma glucose (P=0·023) by multivariable linear regression. For men, tertile 3 of the ‘fruits, eggs and juice’ pattern was associated with an 88 % greater risk (hazard ratio=1·88; 95 % CI 1·04, 3·54) of hyperglycaemia than tertile 1 of this pattern. Being in tertile 3 of the ‘alcohol, milk and tea’ pattern was associated with a 35 % greater risk (hazard ratio=1·35; 95 % CI 1·04, 2·16) relative to tertile 1 in women, while for the ‘'healthy traditional’ pattern tertile 3 was associated with a 41 % lower risk (hazard ratio=0·59; 95 % CI 0·35, 0·99) compared with tertile 1. The ‘condiments’ and the ‘animal and plant protein’ patterns were not independently associated with hyperglycaemia.ConclusionsOur findings suggest that modifying dietary patterns could reduce hyperglycaemia incidence in the mainland Chinese adult population. [ABSTRACT FROM PUBLISHER]

• A set of one-sided Riemann and GRP solver are described systematically. • One-sided GRP solver is applied for numerical boundary conditions. • Both 1-D and 2-D numerical simulations are tested for the resulting schemes. In the computation of compressible fluid flows, numerical boundary conditions are always necessary for all physical variables at computational boundaries while just partial physical variables are often prescribed as physical boundary conditions. Certain extrapolation technique or ghost cells are often employed traditionally for this issue but spurious wave reflections often arise to cause numerical instability. In this paper, we associate this issue with the one-sided generalized Riemann problem (GRP) solver motivated by the accelerated piston problem in gas dynamics so that the extrapolation technique can be actually avoided. In fact, the compatibility arguments naturally require to formulate the one-sided generalized Riemann problem and incorporate it into the numerical procedure of boundary conditions. Once the corresponding solver is available, the boundary control volume is treated in the same way as the usual interior control volume. As far as the interaction of nonlinear waves with physical boundaries, such a one-sided GRP solver shows significant benefits, as numerical experiments demonstrate, on avoiding spurious wave reflections at the computational boundaries. [ABSTRACT FROM AUTHOR]

Examines the Riemann problem for zero-pressure flow in gas dynamics of one dimension and two dimensions. Consideration of the zero-pressure flow in gas dynamics; Solution in one dimension problem; Formation of the large-scale structures in the universe.