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A satellite taxonomy approach was derived from the definition of the satellite energy dissipation rate (EDR) and the atmospheric drag perturbation formula. This approach can group satellites in several EDR bins based on the two-line element (TLE) data. Because it does not need to calculate the satellited ballistic coefficient and atmospheric density model, this approach can provide results to within an accuracy of 1 And the computational complexity of this approach is extremely small. Furthermore, an analytical algorithm for calculating the accuracy versus tracking-density curves of the planar orbit satellite was also proposed in this work based on the extended Kalman filter. The orbit determination accuracy of this algorithm was described through the position covariance matrix of the relative orbit. Simulation results indicate the validity of the EDR calculation approach of this algorithm. Finally, the accuracy versus tracking density curve, which indicated the observation requirement, and the corresponding analysis were provided. Simulation results show that the orbital propagation error is directly proportional to EDR when observations are spare, and that the phenomenon of observation saturation when observations are abundant. [ABSTRACT FROM AUTHOR]

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Abstract: Objective: A major challenge in radiographic identification is the inconsistent orientation between clinical (ante-mortem, AM) and post-mortem (PM) radiographs. The objectivity and accuracy of radiological identification would be greatly enhanced by post-processing techniques that allow quantitative comparison of PM CT data in the same orientation as the AM CT data. Methods: We applied a post-processing technique to reposition a multislice computed tomography (MSCT) scan for spatial registration with a CT radiograph from the same patient. A second set of MSCT images from different individuals served as the non-matched control group. The consistency in radiographic positioning eliminated subjectivity in the comparison and identification process because the radiograph superposition provided objective evidence that confirmed the identification with fine detail. Results: A quantitative comparison with statistical validation was achieved by measuring a set of 14 landmarks from the images. Discrimination of identity based on logistic regression analysis of the earlier CT patient scans (the AM group) versus subsequent MSCT scans (the PM group) was objective and reliable. Conclusion: This quantitative comparison depends less on subjective judgment and the experience of the examiner, and so may meet legal standards. [Copyright &y& Elsevier]

A series of (μ -oxo)bis(μ -carboxylato)diruthenium(III) complexes stabilized by 1,4,7-trimethyl-l,4,7-triazacyclononane ligands were synthesized and structurally characterized and their photocatalytic properties for H 2 evolution by water splitting were also investigated. [Display omitted] • (μ -Oxo)bis(μ -carboxylato)diruthenium(III) complexes with Me 3 tacn ligands were synthesized. • The prepared new ruthenium complexes were characterized by X-ray crystallography. • The photocatalytic H 2 evolution by water splitting of the complexes was investigated. Treatment of [(Me 3 tacn)RuCl 3 ·H 2 O] (Me 3 tacn = 1,4,7-trimethyl-1,4,7-tri-azacyclononane) with substituted benzoic acid or phenylacetic acid, in water in the presence of potassium hexafluorophosphate gave a series of cationic dinuclear Ru(III)–Ru(III) (μ -oxo)bis(μ -carboxylato) complexes [(Me 3 tacn) 2 Ru 2 (μ -O)(μ -OOCR) 2 ](PF 6) 2 (R = Ph, 1 ; -py, 2 ; -C 6 H 4 -2-Cl, 3 ; -C 6 H 3 -2,4-Cl 2 , 4 ; -CH 2 C 6 H 4 -2-CH 3 , 5 ; -CH 2 C 6 H 4 -4-CH 3 , 6 ; -CH 2 C 6 H 4 -4-OCH 3 , 7 ; -CH 2 C 6 H 4 -4-Cl, 8). All complexes are well characterized by infrared, UV/Vis and mass spectroscopies, and their electrochemical properties were also investigated. The molecular structures of 1 , 2 ·2C 3 H 6 O, 5 ·2C 3 H 6 O, 7 and 8 have been also established by single-crystal X-ray diffraction. The photocatalytic properties for H 2 evolution by water splitting of complexes 1 , 2 , 3 , 5 , and 7 were also investigated in the paper. [ABSTRACT FROM AUTHOR]

The open-circuit voltage (V OC) degradation for individual subcell in 1.0 MeV electrons-irradiated GaInP/GaAs/Ge solar cells has been analyzed using electroluminescence (EL) measurements. By using the relationship between V OC degradation and electron fluence, the capture cross section of the defects induced by electron irradiation in individual subcells were determined. Furthermore, by comparing the thermal activation energy and capture cross section, a defect located at E v +0.55 ​eV styled H2 hole trap is nonradiative recombination centre in GaInP subcell, a defect located at E C -0.96 eV styled E5 electron trap is nonradiative recombination centre in GaAs subcell, and a defect located at E C -0.38 eV styled E-center electron trap is nonradiative recombination centre in Ge subcell. • Electroluminescence measurements can analyze subcells' open-circuit voltage. • Determination of the relationship between open-circuit voltage and electron fluence. • Electroluminescence measurements can determine the capture cross section of nonradiative recombination center. • The H2 defect in top-cell, E5 defect in mid-cell and E-center in bot-cell are primary nonradiative recombination centres. [ABSTRACT FROM AUTHOR]

Astrocytes can serve multiple functions in maintaining cellular homeostasis of the central nervous system (CNS), and normal functions for autophagy in astrocytes is considered to have very vital roles in the pathogenesis of aging and neurodegenerative diseases. Autophagy is a major intracellular lysosomal (or its yeast analog, vacuolar) clearance pathways involved in the degradation and recycling of long-lived proteins, oxidatively damaged proteins and dysfunctional organelles by lysosomes. Current evidence has shown that autophagy might influence inflammation, oxidative stress, aging and function of astrocytes. Although the interrelation between autophagy and inflammation, oxidative stress, aging or neurological disorders have been addressed in detail, the influence of astrocytes mediated-autophagy in aging and neurodegenerative disorders has yet to be fully reviewed. In this review, we will summarize the most up-to-date findings and highlight the role of autophagy in astrocytes and link autophagy of astrocytes to aging and neurodegenerative diseases. Due to the prominent roles of astrocytic autophagy in age-related neurodegenerative diseases, we believe that we can provide new suggestions for the treatment of these disorders. [ABSTRACT FROM AUTHOR]

Background: Tens of million cases of coronavirus disease-2019 (COVID-19) have occurred globally. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) attacks the respiratory system, causing pneumonia and lymphopenia in infected individuals. The aim of the present study is to investigate the laboratory characteristics of the viral load, lymphocyte subset and cytokines in asymptomatic individuals with SARS-CoV-2 infection in comparison with those in symptomatic patients with COVID-19. Methods: From January 24, 2020, to April 11, 2020, 48 consecutive subjects were enrolled in this study. Viral loads were detected by RT-PCR from throat-swab, sputum and feces samples. Lymphocyte subset levels of CD3 + , CD4 + , and CD8 + T lymphocytes, B cells and NK cells were determined with biological microscope and flow cytometric analysis. Plasma cytokines (IL2, IL4, IL5, IL6, IL8, IL10, TNF-α, IFN-α and IFN-γ) were detected using flow cytometer. Analysis of variance (ANOVA), Chi-square or Fisher's exact test and Pearson's Correlation assay was used for all data. Results: Asymptomatic (AS), mild symptoms (MS) and severe or critical cases (SCS) with COVID-19 were 11 (11/48, 22.9%), 26 (54.2%, 26/48) and 11 cases (11/48, 22.9%), respectively. The mean age of AS group (47.3 years) was lower than SCS group (63.5 years) (P < 0.05). Diabetes mellitus in AS, MS and SCS patients with COVID-19 were 0, 6 and 5 cases, respectively, and there was a significant difference between AS and SCS (P < 0.05). No statistical differences were found in the viral loads of SARS-CoV-2 between AS, MS and SCS groups on admission to hospital and during hospitalization. The concentration of CD 3 + T cells (P < 0.05), CD3 + CD4 + T cells (P < 0.05), CD3 + CD8 + T cells (P < 0.01), and B cells (P < 0.05) in SCS patients was lower than in AS and MS patients, while the level of IL-5 (P < 0.05), IL-6 (P < 0.05), IL-8 (P < 0.01) and IL-10 (P < 0.01), and TNF-α (P < 0.05) was higher. The age was negatively correlated with CD3 + T cells (P < 0.05), CD3 + CD4 + T cells (P < 0.05), and positively correlated with IL-2 (P < 0.001), IL-5 (P < 0.05), IL-6 (P < 0.05) IL-8 (P < 0.05), and IL-10 (P < 0.05). The viral loads were positively correlated with IL-2 (P < 0.001), IL-5 (P < 0.05), IL-6 (P < 0.05) IL-8 (P < 0.05) and IL-10 (P < 0.05), while negatively correlated with CD 3 + T cells (P < 0.05) and CD3 + CD4 + T cells (P < 0.05). Conclusions: The viral loads are similar between asymptomatic, mild and severe or critical patients with COVID-19. The severity of COVID-19 may be related to underlying diseases such as diabetes mellitus. Lymphocyte subset and plasma cytokine levels may be as the markers to distinguish severely degrees of disease, and asymptomatic patients may be as an important source of infection for the COVID-19. [ABSTRACT FROM AUTHOR]

Grifola frondosa is a valuable edible fungus with high nutritional and medicinal values. The mating systems of fungi not only offer practical strategies for breeding, but also have far-reaching effects on genetic variability. Grifola frondosa has been considered as a sexual species with a tetrapolar mating system based on little experimental data. In the present study, one group of test crosses and six groups of three-round mating experiments from two parental strains were conducted to determine the mating system in G. frondosa. A chi-squared test of the results of the test-cross mating experiments indicated that they satisfied Mendelian segregation, while a series of three-round mating experiments showed that Mendelian segregation was not satisfied, implying a segregation distortion phenomenon in G. frondosa. A genomic map of the G. frondosa strain, y59, grown from an LMCZ basidiospore, with 40.54 Mb and 12 chromosomes, was generated using genome, transcriptome and Hi-C sequencing technology. Based on the genomic annotation of G. frondosa, the mating-type loci A and B were located on chromosomes 1 and 11, respectively. The mating-type locus A coded for the β-fg protein, HD1, HD2 and MIP, in that order. The mating-type locus B consisted of six pheromone receptors (PRs) and five pheromone precursors (PPs) in a crossed order. Moreover, both HD and PR loci may have only one sublocus that determines the mating type in G. frondosa. The nonsynonymous SNP and indel mutations between the A1B1 and A2B2 mating-type strains and the reference genome of y59 only occurred on genes HD2 and PR1/2, preliminarily confirming that the mating type of the y59 strain was A1B2 and not A1B1. Based on the genetic evidence and the more reliable molecular evidence, the results reveal that the mating system of G. frondosa is tetrapolar. This study has important implications for the genetics and hybrid breeding of G. frondosa. [ABSTRACT FROM AUTHOR]