Aim To investigate the factors associated with the duration of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) RNA shedding in patients with coronavirus disease 2019 (COVID‐19). Methods A retrospective cohort of COVID‐19 patients admitted to a designated hospital in Beijing was analyzed to study the factors affecting the duration of viral shedding. Results The median duration of viral shedding was 11 days (IQR, 8‐14.3 days) as measured from illness onset. Univariate regression analysis showed that disease severity, corticosteroid therapy, fever (temperature>38.5℃), and time from onset to hospitalization were associated with prolonged duration of viral shedding ( p <0.05). Multivariate regression analysis showed that fever (temperature>38.5℃) (OR 5.1, 95%CI: 1.5‐18.1), corticosteroid therapy (OR 6.3, 95%CI: 1.5‐27.8), and time from onset to hospitalization (OR 1.8, 95%CI: 1.19‐2.7) were associated with increased odds of prolonged duration of viral shedding. Conclusions Corticosteroid treatment, fever (temperature>38.5℃), and longer time from onset to hospitalization were associated with prolonged viral shedding in COVID‐19 patients. This article is protected by copyright. All rights reserved.

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Cordyceps cicadae is an entomogenous fungus with important uses in traditional Chinese medicine. However, its wild resources have not met consumers’ demand due to excessive harvesting practices. Artificial cultivation is therefore an important alternative, but research on cultivating C. cicadae in natural habitats has not been reported. In this study, we aimed to explore the viability of cultivating C. cicadae in a natural habitat, in the soil of Pinus massoniana forest. We assessed and compared the yield, metabolite contents and bacterial community composition of C. cicadae grown in the Antheraea pernyi pupae at different growth stages, and under different cultivation conditions, in the soil of a natural habitat and in sterile glass bottles. Our results showed that cultivating C. cicadae in a natural habitat is feasible, with up to 95% of pupae producing C. cicadae fruiting bodies. The content of nitrogen compounds (amino acids) in C. cicadae cultivated in a natural habitat was significantly higher than in glass bottles, while the yield and carbon compound (mannitol and polysaccharide) and nucleoside (cordycepin and adenosine) contents were lower. Different bacterial genera were enriched in C. cicadae at different growth stages and cultivation environments, and these bacterial genera were closely related to metabolites contents during growth. This study demonstrated the viability of a novel cultivation method of C. cicadae, which could be used as an alternative to wild stocks of this fungus. These findings provided new insights into the growth mechanism of C. cicadae and its interaction with soil microorganisms.

Hepatitis G virus or GB virus C (GBV-C) is a human virus of the Flaviviridae family that is structurally and epidemiologically closest to hepatitis C virus, but replicates primarily in lymphocytes. Co-infection with GBV-C has been reported to confer beneficial outcomes in some HIV-positive patients. Up to now, however, studies on GBV-C infection in the central nervous system (CNS) of HIV-infected patient have rarely been reported. Herein, we report on a 32-year-old HIV-1-infected patient with cerebral toxoplasmosis and fungal encephalitis. GBV-C viral loads were detected in CSF by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR), and the results showed that GBV-C viral load was 6·5 log copies/ml. We amplified and sequenced the E2 and 5'-untranslated regions from the purified viral RNA from CSF by RT-PCR. Both sequences belong to genotype 3 and there were some minor nucleotide divergence among the E2 sequences from the CSF of the patient. These data suggest that GBV-C may be able to penetrate the blood-brain barrier and colonize the CNS of HIV-infected patients. However, the exact mechanisms and potential effect of the infected GBV-C in CNS on HIV-associated neuropathy needs to be further explored.

Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Printer-friendly Version Interactive Discussion Abstract Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Printer-friendly Version Interactive Discussion AbstractWe have developed a fractal analysis method to estimate the dimension of well logging curves in Liaohe oil field, China. The box counting and correlation dimension are methods that can be applied to predict the texture of volcanic rocks with calculation the fractal dimension of well logging curves. The well logging curves are composed 5 of gamma ray (GR), compensated neutron logs (CNL), acoustic (AC), density (DEN), Resistivity lateral log deep (R LLD ), every curve contains a total of 6000 logging data. The dimension of well logging curves are calculated using box counting and correlation algorithms respectively. It is shown that two types of dimension of CNL, DEN and AC have the same average value. The box counting dimension of volcanic lava is lower 10 than the pyroclastic rock obviously. The majority of correlation dimension of volcanic lava is lower than the pyroclastic rock, but a small amount of correlation dimension of volcanic lava is equal to the pyroclastic rock. It is demonstrated that the box counting dimension is more suitable for predicting the texture of volcanic rocks. Applications to logging data, A well show the relationship between the fractal dimension and the 15 texture of volcanic rock in certain depth. 25 analysis and calculating method of fractal dimension (Dimri, 1998; Tarquis et al., 2 NPGD Abstract Introduction Conclusions References Tables NPGD Abstract Introduction Conclusions References Tables 10 NPGD Abstract 20The result is shown in Fig. 2. Correlation dimensionCorrelation dimension represent the association degree of data series. On the basis of the embedding theory and the idea of phase space reconstruction, Grassberger 5 NPGDAbstract Introduction Conclusions References Tables NPGD Abstract Introduction Conclusions References Tables 20 7 NPGD Abstract Introduction Conclusions References Tables NPGD Abstract Introduction Conclusions References Tables NPGD Abstract Introduction Conclusions References Tables Abstract Introduction Conclusions References Tables Abstract Introduction Conclusions References Tables Abstract Introduction Conclusions References Tables Abstract Introduction Conclusions References Tables Abstract Introduction Conclusions References Tables

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The reaction mechanisms for acetylene cyclotrimerization using TiO 2 and Ti catalysts were studied by the density functional theory (DFT) method. Interestingly, the reaction catalysed by TiO 2 occurs on the potential energy surface (PES) with a singlet state. For the same reaction catalysed by Ti, spin-orbit coupling (SOC) calculations were performed to discuss spin inversion between the triplet and singlet PESs. The chance that an electron hops in the vicinity of the minimum-energy crossing point (MECP) was verified regarding the Landau-Zener model. The possibilities of single (P ISC 1 ) and double (P ISC 2 ) at MECP1 (SOC = 253.38 cm −1 ) are about 0.35 and 0.46, respectively. The energetic span model developed by Kozuch was applied in the above reactions. The turnover frequency (TOF)-determining transition state (TDTS) and TOF-determining intermediate (TDI) were verified. The TOF value indicates that Ti is a more active catalyst compared with TiO 2 in C 2 H 2 cyclotrimerization.