High-degree discontinuous finite element discrete quadrature sets for the Boltzmann transport equation
In: Progress in nuclear energy: the international review journal covering all aspects of nuclear energy, Band 153, S. 104403
ISSN: 0149-1970
162 Ergebnisse
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In: Progress in nuclear energy: the international review journal covering all aspects of nuclear energy, Band 153, S. 104403
ISSN: 0149-1970
In: Environmental science and pollution research: ESPR, Band 30, Heft 3, S. 6875-6890
ISSN: 1614-7499
In: Materials and design, Band 196, S. 109119
ISSN: 1873-4197
In: Environmental sciences Europe: ESEU, Band 32, Heft 1
ISSN: 2190-4715
Abstract
Background
Although listed in the Stockholm Convention, commercial Decabromodiphenyl ether (c-DecaBDE) is still being produced in many factories and used as a kind of flame retardants primarily in plastic polymers and textiles. Widespread use offered many exposure ways of its major ingredient, BDE-209, to humans and the environment. Most current studies of BDE-209 focused on the health effects and toxicity of thyroid disruption, oxidative stress, neurotoxicity, and reproductive function, but seldom spread light on the relationship between neurobehavioral toxicity and visual dysfunction. Using zebrafish larvae model, we hope to uncover the potential relationship between the neurobehavioral and visual effects after exposure to BDE-209.
Results
BDE-209 exposure could not induce the changes of locomotion and path angle in 5 days post fertilization (dpf) larvae; however, 5 μg/L BDE-209 exposure caused locomotor hyperactivity and more responsive turns at 7 dpf. The social activity of 50 μg/L exposure group was significantly higher than the control group at 6 dpf. Besides, 5 and 50 μg/L exposure caused the upregulation and downregulation of four cone opsin genes, respectively. The expression of rhodopsin gene was not influenced by both concentration exposures.
Conclusion
The neurobehavioral effects induced by 5 μg/L BDE-209 exposure were consistent with the upregulation of four cone opsins in 7 dpf larvae. The low concentration of BDE-209 exposure caused the hyperactivity and more responsive turns of larvae possibly contributing to the disruption on the cone opsin expressions of larvae. Our results would provide the mechanism cue of neurobehavioral toxicity after BDE-209 exposure and call for more attention on the ecotoxicology studies of BDE-209.
SSRN
Working paper
In: Environmental science and pollution research: ESPR, Band 26, Heft 34, S. 34884-34895
ISSN: 1614-7499
In: Liu, X., Zhang, B., Susarla, A., and Padman, R. (2020) Go to YouTube and See Me Tomorrow: Social Media and Self-Care of Chronic Conditions. MIS Quarterly, 44(1b), 257–283.
SSRN
In: Progress in nuclear energy: the international review journal covering all aspects of nuclear energy, Band 110, S. 236-244
ISSN: 0149-1970
In: Science and technology of nuclear installations, Band 2018, S. 1-10
ISSN: 1687-6083
The discrete ordinates method (SN) is one of the mainstream methods for neutral particle transport calculations. Assessing the quality of the numerical solution and controlling the discrete error are essential parts of large-scale high-fidelity simulations of nuclear systems. Three error estimators, a two-mesh estimator, a residual-based estimator, and a dual-weighted residual estimator, are derived and implemented in the ARES transport code to evaluate the error of zeroth-order spatial discretization for SN equations. The difference in scalar fluxes on coarse and fine meshes is adopted to indicate the error in the two-mesh method. To avoid zero residual in zeroth-order discretization, angular fluxes within one cell are reconstructed by Legendre polynomials. The error is estimated by inverting the discrete transport operator using the estimated directional residual as an anisotropic source. The inner product of the forward directional residual and the adjoint angular flux is employed to quantify the error in quantities of interest which can be denoted by a linear functional of forward angular flux. Method of Manufactured Solutions (MMS) is adopted to generate analytical solutions for SN equation with scattering and the determined true error is used to evaluate the effectivity of these estimators. Promising results are obtained in the numerical results for both homogeneous and heterogeneous cases. The larger error region is well captured and the average effectivity index for the local error estimation is less than unity. For the series test problems, the estimated goal quantity error can be contained within an order of magnitude around the exact error.
In: Fox School of Business Research Paper No. 18-053
SSRN
Working paper
In: Science and technology of nuclear installations, Band 2016, S. 1-10
ISSN: 1687-6083
Maintaining the structural integrity of the reactor pressure vessel (RPV) is a critical concern related to the safe operation of nuclear power plants. To estimate the structural integrity over the designed lifetime and to support analyses for a potential plant life extension, an accurate calculation of the fast neutron fluence (E>1.0 MeV orE>0.1 MeV) at the RPV is significant. The discrete ordinates method is one of the main methods to solve such problems. During the calculation process, many factors will affect the results. In this paper, the deviations introduced by different differencing schemes and mesh sizes on the AP1000 RPV fast neutron fluence have been studied, which are based on new discrete ordinates code ARES. The analysis shows that the differencing scheme (diamond difference with or without linear zero fix-up, theta weighted, directional theta weighted, and exponential directional weighted) introduces a deviation within 4%. The coarse mesh (4 × 4 cm meshes inXYplane) leads to approximately 23.7% calculation deviation compared to those of refined mesh (1 × 1 cm meshes inXYplane). Comprehensive study on the deviation introduced by differencing scheme and mesh size has great significance for reasoned evaluation of RPV fast neutron fluence calculation results.
In: Land use policy: the international journal covering all aspects of land use, Band 42, S. 751-758
ISSN: 0264-8377
In: Social behavior and personality: an international journal, Band 41, Heft 7, S. 1141-1152
ISSN: 1179-6391
We examined the role of perceived social support in the relationship between perfectionism and depression/anxiety. Partial correlation and hierarchical regression were conducted using cross-sectional data from 426 college students. They completed questionnaires including positive and
negative perfectionism scales, the Depression Anxiety Stress Scale-21, and the Multidimensional Scale of Perceived Social Support. Results showed that depression/anxiety were significantly correlated with perceived social support and perfectionism. Perceived social support significantly moderated
the influence of perfectionism upon depression/anxiety. These findings indicate that perceived social support may have a protective effect in preventing perfectionists from experiencing depression and anxiety.
In: Social behavior and personality: an international journal, Band 41, Heft 1, S. 123-134
ISSN: 1179-6391
We examined emotional eating among undergraduates in China. The Emotional Eating Scale (EES; Arnow, Kenardy, & Agras, 1995) was translated into Chinese and adapted to assess intensity and frequency of eating in response to different emotions. A factor analysis generated 4 subscales
of emotions for which eating is a response: anxiety, depression, anger/hostility, and positive emotion. Internal consistency reliability for the subscales was established (Cronbach's alpha = .817, .852, .832, and .861, respectively). Moderate correlations were found between all subscales,
eating pathology, and impulsive control. Positive emotion and negative emotion were found to play an important role in eating behavior. As there was a strong relationship between emotional eaters, especially negative emotional eaters, and eating psychopathology, these individuals may be at
high risk of developing an eating disorder and/ or becoming obese.
In: Socio-economic planning sciences: the international journal of public sector decision-making, Band 42, Heft 1, S. 46-55
ISSN: 0038-0121