The clinical features and immune responses of asymptomatic individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have not been well described. We studied 37 ...asymptomatic individuals in the Wanzhou District who were diagnosed with RT-PCR-confirmed SARS-CoV-2 infections but without any relevant clinical symptoms in the preceding 14 d and during hospitalization. Asymptomatic individuals were admitted to the government-designated Wanzhou People's Hospital for centralized isolation in accordance with policy
. The median duration of viral shedding in the asymptomatic group was 19 d (interquartile range (IQR), 15-26 d). The asymptomatic group had a significantly longer duration of viral shedding than the symptomatic group (log-rank P = 0.028). The virus-specific IgG levels in the asymptomatic group (median S/CO, 3.4; IQR, 1.6-10.7) were significantly lower (P = 0.005) relative to the symptomatic group (median S/CO, 20.5; IQR, 5.8-38.2) in the acute phase. Of asymptomatic individuals, 93.3% (28/30) and 81.1% (30/37) had reduction in IgG and neutralizing antibody levels, respectively, during the early convalescent phase, as compared to 96.8% (30/31) and 62.2% (23/37) of symptomatic patients. Forty percent of asymptomatic individuals became seronegative and 12.9% of the symptomatic group became negative for IgG in the early convalescent phase. In addition, asymptomatic individuals exhibited lower levels of 18 pro- and anti-inflammatory cytokines. These data suggest that asymptomatic individuals had a weaker immune response to SARS-CoV-2 infection. The reduction in IgG and neutralizing antibody levels in the early convalescent phase might have implications for immunity strategy and serological surveys.
Defect engineering is a well‐established approach to customize the functionalities of perovskite oxides. In demanding high‐power applications of piezoelectric materials, acceptor doping serves as the ...state‐of‐the‐art hardening approach, but inevitably deteriorates the electromechanical properties. Here, a new hardening effect associated with isolated oxygen vacancies for achieving well‐balanced performances is proposed. Guided by theoretical design, a well‐balanced performance of mechanical quality factor (Qm) and piezoelectric coefficient (d33) is achieved in lead‐free potassium sodium niobate ceramics, where Qm increases by over 60% while d33 remains almost unchanged. By atomic‐scale Z‐contrast imaging, hysteresis measurement, and quantitative piezoresponse force microscopy analysis, it is revealed that the improved Qm results from the inhibition of both extrinsic and intrinsic losses while the unchanged d33 is associated with the polarization contributions being retained. More encouragingly, the hardening effect shows exceptional stability with increasing vibration velocity, offering potential in material design for practical high‐power applications such as pharmaceutical extraction and ultrasonic osteotomes.
A novel strategy is developed for the hardening of piezoelectrics via the mediation of dopant‐exclusive oxygen vacancies to overcome the long‐term issue: the dilemma between the mechanical quality factor and piezoelectricity coefficient. The approach also makes the high‐power performance superior to many state‐of‐the‐art counterparts, offering a possible route to various piezoelectrics for high‐end applications.
•CCS technology lock-in risk of coal-fired power plants in China was considered.•The cost of CCS commercialization in different scenarios was evaluated.•CCS retrofit potential of coal-fired power ...plants in China was explored.•Suggestions on CCS promotion and avoiding CCS technology lock-in were put forward.
Carbon capture and storage (CCS) has been discussed intensively in China; however, the CCS technology lock-in risk has been neglected for a long time and may have a negative impact on understanding the CCS application potential. Thus, from the perspective of avoiding a technology lock-in, a learning curve model and a cost-optimization model are employed in this study to explore the total cost of CCS commercialization and the national and provincial CCS retrofit potential of coal-fired power plants in China. The results show that if the second-generation CCS technologies are not commercially applied by 2040, coal-fired power plants in China may face a huge risk of being locked in by the first-generation technologies with a retrofit potential of only 0–143.63 GW (GW = 106 kW) and a cost of 13.39 billion USD. Advancing the CCS commercialization time to 2030 can reduce the technology lock-in risk greatly and increase the CCS retrofit potential to 431.01–499.90 GW, which would cost 54.3 billion USD. Considering the cost input, the technology lock-in risk, and the CCS retrofit demand, 2035 is regarded a suitable time for CCS commercialization in China with a retrofit potential of 143.63–431.04 GW and 31.46 billion USD cost input. Moreover, at the regional level, there is a great CCS retrofit potential of coal-fired power plants in Shaanxi, Hebei, and Inner Mongolia. Policymakers should provide greater support for the second-generation CCS technologies and promote them actively in 2030–2035, especially in Shaanxi, Hebei, and Inner Mongolia, to achieve CCS commercialization and control the CO2 emissions of coal-fired power plants in China.
Hydrogen has increasingly been an attractive energy in the context of carbon neutrality. The traditional coal-to-hydrogen process (C2H) is cost-effective, while has high CO2 emissions. In contrast, ...low-carbon hydrogen production technologies such as coal-to-hydrogen coupled CCS (C2HCCS) and renewable energy electrolysis of water for hydrogen production may be climate friendly, but of the economic feasibility needs to be evaluated. This study analyzed the production cost, cost structure and regional differences of C2H, C2HCCS, alkaline electrolysis (ALK), and proton exchange membrane electrolysis (PEM) in China via the levelized cost of hydrogen (LCOH) model. The main findings include: (1) The LCOH of the C2HCCS is 13.1–19.4RMB/kg, which is 57.6–128.3% higher than the coal-to-hydrogen process (7.2–10.1RMB/kg), and 20.5–61.0% lower than that of the hydrogen production via the water electrolysis powered by renewable energy (16.4–51.8RMB/kg). (2) The C2HCCS can be considered as a cost-effectiveness option in northwestern regions of China, especially in the provinces of Inner Mongolia, Xinjiang, and Gansu, for the future blue hydrogen energy industry. (3) Currently, hydrogen production via renewable energy-based water electrolysis has no cost advantage in most regions, but wind power-based electrolysis in Gansu and photovoltaic power-based electrolysis in Chongqing have the potential to compete with the C2HCCS process.
•The levelized costs of low-carbon hydrogen production technologies were evaluated.•High initial capital cost greatly limits the development of low-carbon hydrogen.•Coal-to-hydrogen with CCS is usually cost-effective in northern China.•Gansu and Chongqing have great potential for hydrogen production by renewable energy.•Regional advantages of various processes help reduce the cost of hydrogen production.
With growing concern over world environmental problems and increasing legislative restriction on using lead and lead-containing materials, a feasible replacement for lead-based piezoceramics is ...desperately needed. Herein, we report a large piezoelectric strain (d 33*) of 470 pm/V and a high Curie temperature (T c) of 243 °C in (Na0.5K0.5)NbO3-(Bi0.5Li0.5)TiO3-BaZrO3 lead-free ceramics by doping MnO2. Moreover, excellent temperature stability is also observed from room temperature to 170 °C (430 pm/V at 100 °C and 370 pm/V at 170 °C). Thermally stimulated depolarization currents (TSDC) analysis reveals the reduced defects and improved ferroelectricity in MnO2-doped piezoceramics from a macroscopic view. Local poling experiments and local switching spectroscopy piezoresponse force microscopy (SS-PFM) demonstrates the enhanced ferroelectricity and domain mobility from a microscopic view. Distinct grain growth and improvement in phase angle may also account for the enhancement of piezoelectric properties.
As a conserved protein interaction module that recognizes and binds to acetylated lysine, bromodomain (BRD) contains a deep, largely hydrophobic acetyl lysine binding site. Proteins that share the ...feature of containing two BRDs and an extra-terminal domain belong to BET family, including BRD2, BRD3, BRD4 and BRDT. BET family proteins perform transcription regulatory function under normal conditions, while in cancer, they regulate transcription of several oncogenes, such as c-Myc and Bcl-2. Thus, targeting BET proteins may be a promising strategy, and intense interest of BET proteins has fueled the development of structure-based bromodomain inhibitors in cancer. In this review, we focus on summarizing several small-molecule BET inhibitors and their relevant anti-tumor mechanisms, which would provide a clue for exploiting new targeted BET inhibitors in the future cancer therapy.
Summary Background Helicobacter pylori is one of the most common gastric pathogens, affecting at least half the world's population, and is strongly associated with gastritis, peptic ulcer, gastric ...adenocarcinoma, and lymphoma. We aimed to assess the efficacy, safety, and immunogenicity of a three-dose oral recombinant H pylori vaccine in children in China. Methods We did this randomised, double-blind, placebo-controlled, phase 3 trial at one centre in Ganyu County, Jiangsu Province, China. Healthy children aged 6–15 years without past or present H pylori infection were randomly assigned (1:1), via computer-generated randomisation codes in blocks of ten, to receive the H pylori vaccine or placebo. Participants, their guardians, and study investigators were masked to treatment allocation. The primary efficacy endpoint was the occurrence of H pylori infection within 1 year after vaccination. We did analysis in the per-protocol population. This trial is registered with ClinicalTrials.gov , number NCT02302170. Findings Between Dec 2, 2004, and March 19, 2005, we randomly assigned 4464 participants to either the vaccine group (n=2232) or the placebo group (n=2232), of whom 4403 (99%) participants completed the three-dose vaccination schedule and were included in the per-protocol efficacy analysis. We extended follow-up to 3 years. We recorded 64 events of H pylori infection within the first year (14 events in 2074·3 person-years at risk in the vaccine group vs 50 events in 2089·6 person-years at risk in the placebo group), resulting in a vaccine efficacy of 71·8% (95% CI 48·2–85·6). 157 (7%) participants in the vaccine group and 161 (7%) participants in the placebo group reported at least one adverse reaction. Serious adverse events were reported in five (<1%) participants in the vaccine group and seven (<1%) participants in the placebo group, but none was considered to be vaccination related. Interpretation The oral recombinant H pylori vaccine was effective, safe, and immunogenic in H pylori -naive children. This vaccine could substantially reduce the incidence of H pylori infection; however, follow up over a longer period is needed to confirm the protection of the vaccine against H pylori -associated diseases. Funding Chongqing Kangwei Biological Technology.
•A high precision CCUS source-sink matching model was proposed.•Deployment potential of CCUS in coal-fired power plants in China was evaluated.•Early opportunities for China to develop CCUS were ...identified.•Suggestions on CCUS deployment in China were put forward.
Carbon capture utilization and storage is regarded as an important option to achieve deep CO2 reduction in the power sector, especially in China. An optimization model was developed without considering the CCUS costs constraints to determine the CO2 reduction potential of existing coal-fired power plants with CCUS in China from the perspective of source-sink matching. Saline aquifers and oil fields located in major onshore sedimentary basins in China were considered as potential sinks. The results showed that: i) the storage potential of the saline aquifers and enhanced oil recovery are over 1 × 1012 t and 5 × 109 t, respectively; ii) 401 power plants could be matched with storage sites within 100 km without considering the CO2 injection capacity, and the annual CO2 sequestration amount was about 1204 Mt. If the maximum transport distance were increased to 250 km and 800 km, respectively, and the annual CO2 sequestration amount would more than 1620 Mt and 1017 Mt. iii) The CO2 sequestration amount would be cut by about 2% to 38% if the CO2 injection capacity was considered as a constraint; the sequestration amount was primarily affected by the transport distance. iv) Junggar Basin, Turpan-Hami Basin, Ordos Basin, Songliao Basin, and Bohai Bay Basin were considered priority areas to deploy carbon capture utilization and storage technology, including CO2 enhanced oil recovery.
The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in an unprecedented public health crisis. Because of the novelty ...of the virus, there are currently no SARS-CoV-2-specific treatments or vaccines available. Therefore, rapid development of effective vaccines against SARS-CoV-2 are urgently needed. Here, we developed a pilot-scale production of PiCoVacc, a purified inactivated SARS-CoV-2 virus vaccine candidate, which induced SARS-CoV-2-specific neutralizing antibodies in mice, rats, and nonhuman primates. These antibodies neutralized 10 representative SARS-CoV-2 strains, suggesting a possible broader neutralizing ability against other strains. Three immunizations using two different doses, 3 or 6 micrograms per dose, provided partial or complete protection in macaques against SARS-CoV-2 challenge, respectively, without observable antibody-dependent enhancement of infection. These data support the clinical development and testing of PiCoVacc for use in humans.
The first silver nanocluster with an octahedral template of TeO6 6– was synthesized as a neutral 36-nucleus nanocluster, and its structure was demonstrated using single-crystal X-ray diffraction, ...Fourier transform infrared spectroscopy, electrospray ionization mass spectrometry, and X-ray photoelectron spectroscopy. The peripheral ligands of the cagelike skeleton of the nanocluster are CF3COO– and tBuCC–. During the synthesis, the TeO6 6– template arranged the nanocluster, and a 36-nucleus nanocluster was formed. The effect of the template nature was displayed on the structural features of the nanocluster in comparison with an 8-nucleus cluster, with the same synthesis conditions. The photoluminescence and UV–vis absorption analyses of the nanocluster were also investigated. The nanocluster displayed near-infrared luminescence emission at 690 nm.
PDF
