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The Middle and Upper Permian Dalong and Gufeng Formations in South China have recently been considered as potential gas-producing shales. However, their pore structure characteristics remain poorly understood. To investigate the pore structure and fractal characteristics of the pores in these two formations, a suite of shale samples from the Dalong and Gufeng Formations in the western Hubei Province, South China were analyzed by multiple techniques, namely, TOC content, X-ray diffraction (XRD) mineralogy analysis, optical microscopy observations, major elemental analysis, field emission-scanning electron microscopy (FE-SEM), and low-pressure gas adsorption measurements (N2 and CO2). The identified major shale lithofacies include siliceous mudstone, carbonaceous mudstone, argillaceous-siliceous mixed mudstone, and calcareous-siliceous mixed mudstone. SEM images show that the dominant pore types include the pores between brittle minerals, slit-shaped pores between clay sheets, and secondary organic matter (OM) pores within solid bitumen. The pore size distribution is dominated by micropores and mesopores (<30 nm), which are the major contributors to total pore volume and surface area for the Dalong and Gufeng Formations. Based on the Frenkel–Halsey–Hill (FHH) method, fractal dimensions (D1, D2) calculated from the nitrogen adsorption data have a range of from 2.489 to 2.772 (D1) and from 2.658 to 2.963 (D2), and are higher in the Gufeng Formation (average TOC = 8.3 wt.%) due to a higher TOC content comparing to the Dalong Formation (average TOC = 6.2 wt.%). The pore development and fractal characteristics are primarily controlled by organic matter (OM), carbonate minerals, and clay minerals for both the Dalong and Gufeng Formations. Shale samples with high TOC content, low carbonate content, and high clay content tend to develop more heterogeneous micropores and mesopores, which is ascribed to the generation of clay-related and OM-hosted pores, along with the destruction of primary pores by pore-filling carbonate cements. [ABSTRACT FROM AUTHOR]

The organic-rich shales found in the Wufeng–Longmaxi Formation are typically deposited in oxygen-deficient reducing environments. One of the primary sources of debate revolves around the question of whether the anoxic bottom water found in these shales is either euxinic or ferruginous, and this matter remains unresolved. Previous studies have mostly focused on the Wufeng–Longmaxi Formation as a whole in order to understand the key factors that control organic matter accumulation (OMA). However, research on OMA for each member, including the Wufeng Formation (WF), the lower Longmaxi Formation (LLM), and the upper Longmaxi Formation (ULM), has been insufficient. This paper aims to investigate the palaeoenvironmental conditions and OMA mechanisms of the Wufeng–Longmaxi shales in western Hubei by integrating data on total organic carbon (TOC) content, mineral compositions, major and trace elements, and iron speciation. The results indicate that the Wufeng–Longmaxi shales were deposited under highly restricted hydrographic conditions, except for relatively open and upwelling conditions in the upper WF. Silica in the upper WF was primarily biogenic origin and not hydrothermal. Ferruginous conditions were the primary redox conditions for organic-rich shales except for minor formations in the lower LLM that were deposited under euxinic conditions. Due to the tectonic uplift caused by the Kwangsian Orogeny in the upper LLM, the palaeoenvironment was characterized by a warmer and wetter climate, high terrigenous influx, oxic conditions, and low productivity as the result of the insufficient nutrients caused by the weak upwelling, leading to the turnover of graptolite biozones from LM5 to LM6. The factors influencing OMA changed vertically. TOC contents have a highly positive correlation with Al content, indicating that terrigenous influx was the main factor affecting OMA in the WF, which significantly differed from patterns found in other regions. This suggests that the sedimentation rate of organic matter was higher than the terrigenous dilution rate during the WF stage. The combination of redox conditions and productivity were the main factors affecting OMA in the LLM, while terrigenous influx was the key factor controlling OMA in the ULM, resulting in the dilution of organic matter. Regions in the eastern Yiling block, which are close to the Qinling Ocean, show better prospects for shale gas exploration. This research will further facilitate the development of shale gas in this area. [ABSTRACT FROM AUTHOR]

This study applies 3-stage data envelopment (DEA) of 24 listed companies in the development zone of Hubei Province from 2012 to 2017 based on the panel data; we used the DEA-Tobit model and regression analysis method on the sample in order to measure the factors affecting the innovation efficiency of listed companies and the efficiency of corporate innovation. The results demonstrated that the innovation efficiency of listed companies in the development zone of Hubei Province is relatively low. It is necessary to improve the innovation system of the development zone and give the full initiative to the role of corporate innovation as a mainstay. The four environmental variables of the number of enterprises, government subsidies, foreign direct investment in the development zone, and fixed asset investment have a significant impact on innovation efficiency. The enterprise size, operating capacity, and state-owned shares of the company have a significant positive impact on the innovation efficiency. But the number of years of the establishment has a significant negative impact on innovation efficiency. Moreover, the quality of the workers is not significant. Therefore, we must increase government investment in innovation to expand the scale of listed companies in the development zone, improve the environment for foreign investment, further strengthen the construction of talented people of companies, and enhance the original ability of innovation. [ABSTRACT FROM AUTHOR]

To characterize hantaviruses currently circulating in the hemorrhagic fever with renal syndrome (HFRS) epidemic area of Hubei Province, rodents were captured and serum samples were collected from several HFRS patients. The partial S segment of the hantaviruses amplified from two serum samples had a high degree of sequence identity to the corresponding hantavirus strain isolated from Apodemus agrarius (designated as HV004). The complete S, M, and L segment sequences of HV004 were determined. The sequence identities between strain HV004 and other Hantaan viruses (HTNVs) were 83 %-90 % at the nucleotide level and 95 %-99 % at the amino acid level. Phylogenetic analysis showed that HV004 belonged to a new HTNV lineage. These data suggest the presence of a new HTNV subtype, which probably caused the HFRS cases in the endemic area of Hubei Province. [ABSTRACT FROM AUTHOR]

• HV004 strain showed higher proliferation efficiency and pathogenicity. • The inactivated HTNV vaccine was administered safely in immunized BALB/C mice. • The vaccine induced sufficient neutralizing antibodies and cellular immune response. Hantaan virus (HTNV, Orthohantavirus hantanensae species, Hantaviridae family) is the main etiological agent responsible for hemorrhagic fever with renal syndrome (HFRS). The novel HTNV may pose a potential danger to the control and prevention of HFRS in China, which highlights the importance of vaccine development in public health management. In previous studies, our laboratory discovered and successfully isolated a new HTNV strain, HV004 strain, from Apodemus agrarius captured in an epidemic area in Hubei, China. An initial biological and pathogenicity characterization of HTNV 76–118 (standard train), HV114 strain (a clinical isolate from Hubei province in 1986), and the novel isolate HV004 strain from the epidemic areas of Hubei province were performed in susceptible cells and in vivo. An experimental HV004 strain inactivated vaccine was prepared, and its corresponding immunogenicity was analyzed in BALB/c mice. HV004 strain had a similar but higher pathogenicity than HTNV 76–118 and HV114 in suckling mice. A subcutaneous vaccination (s.c.) with the inactivated HTNV vaccine adjuvanted with aluminum, followed by a challenge intraperitoneally with 106 FFU/ml HTNV, afforded full protection against an HTNV challenge. All immunized mice in every group elicited serum neutralizing antibodies with increasing dosages, which may protect mice from HTNV infection. A dose-dependent stimulation index of splenocytes was also observed in immunized mice. The percentage of IFN-γ-producing CD3+CD8+ T cells was significantly higher in the spleens of immunized mice than in those of control mice. These findings suggest that the inactivated HTNV vaccine may stimulate mice to produce high levels of antibodies with neutralization activity and elicit specific anti-HTNV humoral and cellular immune responses in BALB/c mice against the prevalent strain of HTNV in south central China. [ABSTRACT FROM AUTHOR]

Background: Previous studies on the pneumonia outbreak caused by the 2019 novel coronavirus disease (COVID-19) were based on information from the general population. Limited data are available for pregnant women with COVID-19 pneumonia. This study aimed to evaluate the clinical characteristics of COVID-19 in pregnancy and the intrauterine vertical transmission potential of COVID-19 infection.Methods: Clinical records, laboratory results, and chest CT scans were retrospectively reviewed for nine pregnant women with laboratory-confirmed COVID-19 pneumonia (ie, with maternal throat swab samples that were positive for severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) who were admitted to Zhongnan Hospital of Wuhan University, Wuhan, China, from Jan 20 to Jan 31, 2020. Evidence of intrauterine vertical transmission was assessed by testing for the presence of SARS-CoV-2 in amniotic fluid, cord blood, and neonatal throat swab samples. Breastmilk samples were also collected and tested from patients after the first lactation.Findings: All nine patients had a caesarean section in their third trimester. Seven patients presented with a fever. Other symptoms, including cough (in four of nine patients), myalgia (in three), sore throat (in two), and malaise (in two), were also observed. Fetal distress was monitored in two cases. Five of nine patients had lymphopenia (<1·0 × 10⁹ cells per L). Three patients had increased aminotransferase concentrations. None of the patients developed severe COVID-19 pneumonia or died, as of Feb 4, 2020. Nine livebirths were recorded. No neonatal asphyxia was observed in newborn babies. All nine livebirths had a 1-min Apgar score of 8-9 and a 5-min Apgar score of 9-10. Amniotic fluid, cord blood, neonatal throat swab, and breastmilk samples from six patients were tested for SARS-CoV-2, and all samples tested negative for the virus.Interpretation: The clinical characteristics of COVID-19 pneumonia in pregnant women were similar to those reported for non-pregnant adult patients who developed COVID-19 pneumonia. Findings from this small group of cases suggest that there is currently no evidence for intrauterine infection caused by vertical transmission in women who develop COVID-19 pneumonia in late pregnancy.Funding: Hubei Science and Technology Plan, Wuhan University Medical Development Plan. [ABSTRACT FROM AUTHOR]