China Building Material Test & Certification Group Co., Ltd., Beijing 100024, China.
Published: February 2020
AI Article Synopsis
Article Abstract
Volatile organic compounds (VOCs) concentrations of dry building materials can significantly affect the quality of indoor air. In this paper, a spatial fractional diffusion model is established by introducing fractional Fick's law, based on the fact that the pore structure of porous building materials has a strongly impact on VOCs diffusion. Furthermore, the areal porosity of the material is drawn into the convection mass transfer equation. The relevant parameters are estimated by a kind of optimization algorithm. The fractional nonlinear equations are tackled by the finite difference method combined with L2-algorithm. Results indicate that spatial fractional diffusion model agrees better with the experimental data than Deng and Kim's model. The spatial fractional diffusion model is used to describe the formaldehyde concentration in the particleboard according to the experimental data. Taking formaldehyde as a common substance, the influences of physical parameters on VOCs diffusion are predicted by this model. The results of numerical simulation demonstrate that the diffusion is consistent with the actual situation.
Institute of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
Chronic back pain (CBP) is a global health concern with significant societal and economic burden. While various predictors of back pain chronicity have been proposed, including demographic and psychosocial factors, neuroimaging studies have pointed to brain characteristics as predictors of CBP. However, large-scale, multisite validation of these predictors is currently lacking.
Department of Nuclear Medicine, West China Hospital of Sichuan University, Chengdu, China; Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu, China. Electronic address:
Objective: The overlap of affective disturbance and psychosis considerably makes it complex to determine the etiology of bipolar disorder (BD) and develop targeted interventions. The present study aimed to determine the white matter microstructural alterations that distinguish between BD with psychosis (BDP) and BD with no psychosis (BDNP) to identify patients who may specifically benefit from appropriately effective treatments.
Methods: Diffusion-weighted magnetic resonance images were acquired from 38 participants with BDP, 52 participants with BDNP and 70 healthy controls (HCs).
Objective: The main purpose of this work is to present an exponentially fitted non-polynomial cubic spline method for solving time-fractional singularly perturbed convection-diffusion problem involving large temporal lag.
Result: The time-fractional derivative is considered in the Caputo sense and discretized using backward Euler technique. Then, on uniform mesh discretization, a non-polynomial cubic spline scheme is constructed along the spatial direction.
National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, P.R. China.
Neuroimaging studies revealed that smoking is associated with abnormal white matter (WM) microstructure. However, results are controversial, and the impact of smoking on the WM integrity in young smokers is still unclear. In this study, we used diffusion tensor imaging to investigate the smoking-related WM alterations in young adult smokers.
Background: Interstitial fibrosis and tubular atrophy (IFTA), and density and shape of peritubular capillaries (PTCs), are independently prognostic of disease progression. This study aimed to identify novel digital biomarkers of disease progression and assess the clinical relevance of the interplay between a variety of PTC characteristics and their microenvironment in glomerular diseases.
Methods: A total of 344 NEPTUNE/CureGN participants were included: 112 minimal change disease, 134 focal segmental glomerulosclerosis, 61 membranous nephropathy, and 37 IgA nephropathy.
