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This study uses a hierarchical linear model (HLM) to examine the effects of cognitive ability and self-control on comprehensive academic performance among students in a high school in Beijing. The study included 572 participating students, including 291 boys and 281 girls, ranging in age from 16 to 18 years old. In this study, the individual level of students' cognitive abilities are used as the first-level variables, including memory ability (MA), information processing ability (IPA), representation ability (RA), logical reasoning ability (LRA), and thinking transformation ability (TCA). Consider self-control at the class level as the second-level variable. The research results show that the five cognitive abilities have a significant positive impact on comprehensive academic performance. Self-control plays an active role in regulating the relationship between RA, LRA, TCA, and comprehensive academic performance. [ABSTRACT FROM AUTHOR]

The reflectance anisotropy of land surface serves as an important bridge between surface biophysical parameters and remote sensing observations. It can characterize by the linear kernel-driven bidirectional reflectance distribution function (BRDF), which is the combination of several kernel functions and kernel weights. These kernel weights can be estimated by remote sensing; however, the stability of current kernel weights products is still challenging, especially in urban areas with complex aerosol properties and heterogeneous surfaces. In this paper, we propose a method for robust estimation of kernel weights from the Moderate Resolution Imaging Spectroradiometer (MODIS) surface spectral reflectance products (MxD09GA) data based on the constrained least-squares method (CLSM) and a priori knowledge. The kernel weights data were obtained by the CLSM from 2014 to 2017 in Beijing region of China. Validations were carried out using the MxD09GA and BRDF/Albedo products (MCD43A1). The results show that the time series of kernel weights by the CLSM show small variability over different land cover types. The kernel weights estimated by the CLSM can clearly show the phenological signal and fitting ability of surface spectral reflectance is better than that of the MCD43A1 products in Beijing urban area. Experimental results demonstrate that the CLSM has the potential for the robust estimation of kernel weights in urban areas. [ABSTRACT FROM AUTHOR]

Agricultural and non-agricultural sources emission contribute to atmospheric ammonia (NH 3) and particulate ammonium (NH 4 +). However, our understanding on the sources of NH 3 and NH 4 + in PM 2.5 (particles smaller than 2.5 μm) during the winter period in the urban atmosphere is limited. Here, we measured the concentrations and stable nitrogen isotopic composition (δ15N) of NH 3 and NH 4 + in parallel during December 2018 in urban Beijing to assess the non-agricultural and agricultural sources contributions to NH 3 and NH 4 + in ambient air based on the Chemical Transport Model (CTM), a Bayesian isotope mixing model (SIMMR), and the δ15N signatures that we developed. Our study found weekly NH 4 + and NH 3 concentrations were on average 2.5 ± 1.4 μg m−3 and 3.8 ± 1.7 μg m−3, respectively during December 2018. Weekly concentration weighted δ15N(NH 4 +) values ranged from 4.5‰ to 13.7‰ with an average value of 8.2 ± 3.9‰ during December 2018. After accounting for nitrogen isotopic fractionation from NH 3 gas to NH 4 + conversion, initial δ15N(NH 3) values ranged from −22.5‰ to −12.8‰ with an average value of −17.4 ± 3.5‰. Further, weekly measured δ15N(NH 3) values ranged from −22.2‰ to −10.2‰ (after correction) with an average value of −15.6 ± 5.3‰ during December 2018. Results from two different isotope-based method showed non-agricultural sources contributed 31.2%–63.1%, with an average value of 47.5 ± 14.6%, to NH 4 + and 32.3%–71.2%, with an average of 53.4 ± 16.1%, to ambient NH 3 during December 2018 in Beijing. Results from CMAQ-ISAM suggest non-agricultural sources contributed on average 66.2 ± 1.9% to ambient NH 4 + and 66.4 ± 1.9% to ambient NH 3 during December 2018. Results from this study suggest that agricultural and non-agricultural sources nearly equally contributed to NH 3 and NH 4 + in urban Beijing during December 2018 with an uncertainty range of 13%–19% between isotope-based methods and CTM method. [Display omitted] • Correction is necessary for δ15N values characterized with passive samplers. • Overall non-agricultural sources contributed 47.5 ± 14.6% to NH 4 + in PM 2.5 during December 2018. • Overall non-agricultural sources contributed 53.4 ± 16.1% to NH 3 during December 2018. • The CMAQ-ISAM simulations confirmed the isotope-based source apportionment. [ABSTRACT FROM AUTHOR]

Japanese encephalitis (JE), caused by infection with Japanese encephalitis virus (JEV), is the most important viral encephalitis in Asia. JE incidence has significantly decreased by immunization with live-attenuated vaccine SA14-14-2. However, the duration of immune response overtime after vaccination is inconclusive and may be associated with the risk of JE occurrence in adults. A cross-sectional study was conducted in 961 JE-vaccinated local residents aged 19–20 years in Beijing, China. 620 (65%) and 513 (53%) individuals were anti-JEV IgG antibody and neutralizing antibody (nAb) positive, respectively. The geometric mean titer (GMT) of nAb was 1:11, suggesting a seroprotection among the study population. As for IFN-γ production, peripheral blood mononuclear cell (PBMC) samples isolated from 60 subjects showed negative response following the stimulation with concentrated JEV particles. Overall, longer persistence of nAb response among vaccinees is observed than that of cellular immune response after 17–18 years of vaccination. Taken together, our results not only provide the data for evaluating herd immunity against JEV among vaccinated adults in Beijing but also offer useful information for JE prevention and control in endemic areas. • Half of SA14-14-2-vaccinated adults are anti-JEV IgG and nAb positive in Beijing. • SA14-14-2 could induce long-term immune response against JEV among vaccinated adults. • Our Data is helpful for the prevention and control of JEV in endemic areas. [ABSTRACT FROM AUTHOR]