Human infections with zoonotic coronaviruses (CoVs), including severe acute respiratory syndrome (SARS)-CoV and Middle East respiratory syndrome (MERS)-CoV, have raised great public health concern ...globally. Here, we report a novel bat-origin CoV causing severe and fatal pneumonia in humans.
We collected clinical data and bronchoalveolar lavage (BAL) specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital, Hubei province, China. Nucleic acids of the BAL were extracted and subjected to next-generation sequencing. Virus isolation was carried out, and maximum-likelihood phylogenetic trees were constructed.
Five patients hospitalized from December 18 to December 29, 2019 presented with fever, cough, and dyspnea accompanied by complications of acute respiratory distress syndrome. Chest radiography revealed diffuse opacities and consolidation. One of these patients died. Sequence results revealed the presence of a previously unknown β-CoV strain in all five patients, with 99.8% to 99.9% nucleotide identities among the isolates. These isolates showed 79.0% nucleotide identity with the sequence of SARS-CoV (GenBank NC_004718) and 51.8% identity with the sequence of MERS-CoV (GenBank NC_019843). The virus is phylogenetically closest to a bat SARS-like CoV (SL-ZC45, GenBank MG772933) with 87.6% to 87.7% nucleotide identity, but is in a separate clade. Moreover, these viruses have a single intact open reading frame gene 8, as a further indicator of bat-origin CoVs. However, the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV, indicating that these viruses might use the same receptor.
A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans.
Novel molybdenum(VI/V) POM‐based self‐constructed frameworks MoVI12O24(μ2‐O)12(trz)6(H2O)6 ⋅ 6Hma ⋅ 18H2O (1, Htrz=1H‐1,2,3‐triazole, ma=methylamine), MoVI7O14(μ2‐O)8(trz)5(H2O) ⋅ 7Hma ⋅ 5H2O (2), ...Na3MoV6O6(μ2‐O)9(Htrz)3(trz)3 ⋅ 7.5H2O (3) and MoV8O8(μ2‐O)12(Htrz)8 ⋅ 30H2O (4) have been covalently decorated with tri‐coordinated deprotonated/protonated 1,2,3‐triazoles. Channels with an inner diameter of 7.5 Å were found in 1, whereas a tunnel composed of stacking molecules with an inner diameter of 4.1 Å along the b‐axis exists in 2; it is occupied by free disordered methylamines, showing selective adsorption of O2 and CO2 at 25 °C. Obvious downfield shifts were observed by 13C NMR spectroscopies for methylamines inside the confined channels in 1 and 2. There are diversified pores in 3 and 4, which are formed by the molecules themselves and intermolecular accumulations. Adsorption tests indicate that 3 and 4 are fine adsorption materials for CH4 and CO2 under low pressure that rely on the environments built by the POMs. Correspondingly, 1 and 2 display reversible photoresponsive thermochromism that is subtlety influenced by the channels. The polyoxometalate organic frameworks (POMOFs) with multiple functional adsorptions are easy to assemble. Their photo‐/thermoresponse properties offer a new pathway for the self‐constructions of one‐off hybrid materials that possess the good properties of both POMs and MOFs.
Best of both worlds: Novel intrinsic polyoxometalate (POM)‐based microporous frameworks with 1H‐1,2,3‐triazoles as auxiliary agents possess an impressive interrelated nature derived from both POM and MOFs, for example, excellent adsorption affinities for common gases like CO2, O2 and CH4 as well as admirable photochromic properties.
Due to the uncertainties resulted from environmental changes, the importance of green development has been paid increasingly attention in the world. However, our knowledge of the green development ...level of nine cities in the Pearl River Delta (PRD), China, was still limited. Therefore, this study, based on the analysis on the connotation of green development, employed multi-level evaluation method and entropy method to develop the urban green development evaluation index system from five aspects, including enhancement of living environment, treatment and utilization of pollutant, improvement of ecological efficiency, optimization of economic growth and development of innovative potential. This evaluation index system was further applied to evaluate the green development level of nine cities within PRD. Results showed that significant difference in green development level occurred among cities within PRD. Green development level in Shenzhen, Zhuhai, Guangzhou was relatively higher than that in other cities, with the advantages in improvement of ecological efficiency and optimization of economic growth. Green development level in Zhongshan, Dongguan, Huizhou, Foshan averaged in PRD, while Jiangmen and Zhaoqing had a delayed green development level because of their irrational economic structures and extensive growth patterns though these two cities possessed good ecological environment endowments. In the future, it is necessary for PRD to formulate specific and targeted policies and measures to further upgrade energy structure, transform industrial structure, improve public transportation, enhance forestry carbon sink, and eventually construct low-carbon circular industrial system and development pattern.
•Evaluation system of green development in Pearl River Delta (PRD) is constructed.•The system was applied to evaluate green development level in cities within PRD.•Significant difference in green development level occurred among cities within PRD.•Specific measures are needed for PRD to enhance the urban green development level.
This study develops a theoretical framework of green consumer behavior to determine the effects of personal influence, knowledge of green consumption, attitudes toward green consumption, internal and ...external moderators and examines whether these effects differ significantly among purchasing, using and recycling behaviors. Correlation analysis and multiple regression are applied to assess data collected by a questionnaire survey. The results indicate that attitudes are the most significant predictor of purchasing behavior. Using behavior is mainly determined by income, perceived consumer effectiveness and age, while recycling behavior is strongly influenced by using behavior. These findings have policy implications and improve understanding of green consumer behavior in China.
Starting with the discovery of graphene in 2004, the interest in two‐dimensional materials since then has been exponentially growing. Across many disciplines, their exceptional electrical, chemical, ...thermal, and optical properties have drawn considerable attention that has created an entire field within a decade of their discovery. Driven by the mechanical exfoliation technique that allows for the quick exploration of these two‐dimensional materials and their novel devices, joint efforts have been made in order to understand and exploit their potential, consequently leading to the development of their large‐scale growth. This review focuses on recent studies using ultrafast laser spectroscopy that have revealed the photocarrier dynamics in two‐dimensional materials and laid the foundation of their behavior. We provide a brief introduction on ultrafast laser spectroscopy, discuss several aspects of the photocarrier dynamics, and conclude with our perspective on future developments.
Recent progress on using ultrafast lasers to study two‐dimensional materials is reviewed. Fundamentals of pump–probe spectroscopy and the current understanding of various aspects of photocarrier dynamics, such as thermalization, energy relaxation, exciton formation, exciton–exciton annihilation, recombination, and transport, are discussed. Applications of ultrafast laser spectroscopy on studies of spin dynamics, coherent properties, and van der Waals heterostructures are also introduced.
Ferroptosis is a nonapoptotic cell death process that requires cellular iron and the accumulation of lipid peroxides. In progressive rheumatoid arthritis (RA), synovial fibroblasts proliferate ...abnormally in the presence of reactive oxygen species (ROS) and elevated lipid oxidation. Here we show, using a collagen-induced arthritis (CIA) mouse model, that imidazole ketone erastin (IKE), a ferroptosis inducer, decreases fibroblast numbers in the synovium. Data from single-cell RNA sequencing further identify two groups of fibroblasts that have distinct susceptibility to IKE-induced ferroptosis, with the ferroptosis-resistant fibroblasts associated with an increased TNF-related transcriptome. Mechanistically, TNF signaling promotes cystine uptake and biosynthesis of glutathione (GSH) to protect fibroblasts from ferroptosis. Lastly, low dose IKE together with etanercept, a TNF antagonist, induce ferroptosis in fibroblasts and attenuate arthritis progression in the CIA model. Our results thus imply that the combination of TNF inhibitors and ferroptosis inducers may serve as a potential candidate for RA therapy.
We have systematically investigated the structural, electronic and optical properties of perovskite derivative Cs
3
Sb
2
I
9
under various pressures utilizing first-principles calculations within ...density functional theory. The calculated lattice constants are in good agreement with previous results. From the analysis of electronic properties, we concluded that Cs
3
Sb
2
I
9
is a direct band gap semiconductor with a value of 1.92 eV. The research of bonding properties shows that the bonds of Cs
3
Sb
2
I
9
are covalent bonds, which can increase the stability of the compound. It is noteworthy that the band gap decreases with the pressure increase in the range of 0–20 GPa, and the valence band maximum (VBM) with hybrid characteristics and mainly consisted of I 5
p
orbital and a small amount of Sb 5
s
orbital. Further, we have evaluated for the first time dielectric and optical properties of this compound. In the energy range from 0 to 20 eV, all the optical spectra shift to lower energy as the pressure increases, and the decrement of the absorption coefficient corresponds to the change of the band gap. We found that the optical properties of perovskite derivative Cs
3
Sb
2
I
9
undergo a red shift with increasing pressure. This is the first quantitative theoretical prediction of the optical properties of Cs
3
Sb
2
I
9
compound, and it still awaits experimental confirmation.
Abstract
Background
The high cost and insufficient supply of human papillomavirus (HPV) vaccines have slowed the pace of controlling cervical cancer. A phase III clinical trial was conducted to ...evaluate the efficacy, safety, and immunogenicity of a novel Escherichia coli-produced bivalent HPV-16/18 vaccine.
Methods
A multicenter, randomized, double-blind trial started on November 22, 2012 in China. In total, 7372 eligible women aged 18–45 years were age-stratified and randomly assigned to receive three doses of the test or control (hepatitis E) vaccine at months 0, 1, and 6. Co-primary endpoints included high-grade genital lesions and persistent infection (over 6 months) associated with HPV-16/18. The primary analysis was performed on a per-protocol susceptible population of individuals who were negative for relevant HPV type-specific neutralizing antibodies (at day 0) and DNA (at day 0 through month 7) and who received three doses of the vaccine. This report presents data from a prespecified interim analysis used for regulatory submission.
Results
In the per-protocol cohort, the efficacies against high-grade genital lesions and persistent infection were 100.0% (95% confidence interval = 55.6% to 100.0%, 0 of 3306 in the vaccine group vs 10 of 3296 in the control group) and 97.8% (95% confidence interval = 87.1% to 99.9%, 1 of 3240 vs 45 of 3246), respectively. The side effects were mild. No vaccine-related serious adverse events were noted. Robust antibody responses for both types were induced and persisted for at least 42 months.
Conclusions
The E coli-produced HPV-16/18 vaccine is well tolerated and highly efficacious against HPV-16/18–associated high-grade genital lesions and persistent infection in women.
A novel severe acute respiratory syndrome human coronavirus (SARS HCoV) was identified from respiratory illness patients (named SARS-CoV-2 by ICTV) in December 2019 and has recently emerged as a ...serious threat to world public health. However, no approved drugs have been found to effectively inhibit the virus. Since it has been reported that HIV protease inhibitors can be used as anti-SARS drugs by targeting SARS-CoV-1 3CLpro, we chose six approved anti-HIV drugs and investigated their binding interactions with 3CLpro to evaluate their potential to become clinical drugs for the new coronavirus pneumonia (COVID-19) caused by SARS-CoV-2 infection. The molecular docking results indicate that the 3CLpro of SARS-CoV-2 has a higher binding affinity for all the studied inhibitors than does SARS-CoV-1. Two docking complexes (indinavir and darunavir) with high docking scores were further subjected to MM-PBSA binding free energy calculations to detail the molecular interactions between these two protease inhibitors and SARS HCoV 3CLpro. Our results show that, among the inhibitors tested, darunavir has the highest binding affinity with SARS-CoV-2 and SARS-CoV-1 3CLpro, indicating that it may have the potential to be used as an anti-COVID-19 clinical drug. The mechanism behind the increased binding affinity of HIV protease inhibitors toward SARS-CoV-2 3CLpro (as compared to SARS-CoV-1) was investigated by MD simulations. Our study provides insight into the possible role of structural flexibility during interactions between SARS HCoV 3CLpro and inhibitors and sheds light on structure-based design of anti-COVID-19 drugs targeting SARS-CoV-2 3CLpro.
A novel severe acute respiratory syndrome human coronavirus (SARS HCoV) was identified from respiratory illness patients (named SARS-CoV-2 by ICTV) in December 2019 and has recently emerged as a serious threat to world public health.
In this paper, a selective harmonic current mitigation pulsewidth modulation (SHCM-PWM) technique with low switching frequencies is proposed for grid-connected cascaded H-bridge multilevel rectifiers ...to fully meet harmonic requirements within extended harmonic spectrum. In the proposed technique, instead of using the voltage references to calculate switching angles for the rectifier as in conventional selective harmonic elimination-PWM (SHE-PWM) or selective harmonic mitigation-PWM (SHM-PWM), current references are used to compensate the current harmonics due to both grid voltage harmonics and rectifier input voltage harmonics so as to meet the current harmonic requirements and total demand distortion within the whole harmonic spectrum. Furthermore, the techniques to design the critical parameters including switching frequency, the highest harmonic order that can be mitigated using the proposed current-reference-based technique, and the coupling inductance that can attenuate the current harmonic orders above the highest order are investigated. With the same switching frequency, the proposed SHCM-PWM technique uses smaller coupling inductance to meet higher orders of current harmonic requirements than the conventional SHE-PWM technique. Finally, simulations and experiments were conducted to validate the proposed technique.
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