Reduced binding activity of vaccine serum to omicron receptor-binding domain

Coronavirus disease 2019 (COVID-19) vaccination regimens contribute to limiting the spread of severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2). However, the emergence and rapid transmission of the SARS-CoV-2 variant Omicron raise a concern about the efficacy of the current vaccination strategy. Here, we expressed monomeric and dimeric receptor-binding domains (RBDs) of the spike protein of prototype SARS-CoV-2 and Omicron variant in E. coli and investigated the reactivity of anti-sera from Chinese subjects immunized with SARS-CoV-2 vaccines to these recombinant RBDs. In 106 human blood samples collected from 91 participants from Jiangxi, China, 26 sera were identified to be positive for SARS-CoV-2 spike protein antibodies by lateral flow dipstick (LFD) assays, which were enriched in the ones collected from day 7 to 1 month post-boost (87.0%) compared to those harvested within 1 week post-boost (23.8%) (P < 0.0001). A higher positive ratio was observed in the child group (40.8%) than adults (13.6%) (P = 0.0073). ELISA results showed that the binding activity of anti-SARS-CoV-2 antibody-positive sera to Omicron RBDs dropped by 1.48- to 2.07-fold compared to its homogeneous recombinant RBDs. Thus, our data indicate that current SARS-CoV-2 vaccines provide restricted humoral protection against the Omicron variant

Efficient control of atmospheric sulfate production based on three formation regimes

The formation of sulfate (SO₄²⁻) in the atmosphere is linked chemically to its direct precursor, sulfur dioxide (SO₂), through several key oxidation paths for which nitrogen oxides or NO_x (NO and NO₂) play essential roles. Here we present a coherent description of the dependence of SO₄²⁻ formation on SO₂ and NO_x under haze-fog conditions, in which fog events are accompanied by high aerosol loadings and fog-water pH in the range of 4.7–6.9. Three SO₄²⁻ formation regimes emerge as defined by the role played by NO_x. In the low-NO_x regime, NO_x act as catalyst for HO_x, which is a major oxidant for SO₂, whereas in the high-NO_x regime, NO₂ is a sink for HO_x. Moreover, at highly elevated NO_x levels, a so-called NO₂-oxidant regime exists in which aqueous NO₂ serves as the dominant oxidant of SO₂. This regime also exists under clean fog conditions but is less prominent. Sensitivity calculations using an emission-driven box model show that the reduction of SO₄²⁻ is comparably sensitive to the reduction of SO₂ and NO_x emissions in the NO₂-oxidant regime, suggesting a co-reduction strategy. Formation of SO₄²⁻ is relatively insensitive to NO_x reduction in the low-NO_x regime, whereas reduction of NO_x actually leads to increased SO₄²⁻ production in the intermediate high-NO_x regime

Elatostema qinzhouense (Urticaceae), a new species from limestone karst in Guangxi, China

Elatostema qinzhouense L.F. Fu, A.K. Monro & Y.G. Wei, a new species from Guangxi, China is described and illustrated. Morphologically, E. qinzhouense is most similar to E. hezhouense from which it differs by having smaller size of leaf laminae, fewer and smaller staminate peduncle bracts, longer pistillate peduncle bracts and a larger achene. This result is supported by the molecular evidence. The phylogenetic position of the new species within Elatostema is evaluated using three DNA regions, ITS, trnH-psbA and psbM-trnD, for 107 taxa of Elatostema s.l. (including E. qinzhouense). Bayesian inference (BI) and maximum likelihood (ML) analyses each recovered the same strongly supported tree topologies, indicating that E. qinzhouense is a member of the core Elatostema clade and sister to E. hezhouense. Along with the phylogenetic studies, plastid genome and ribosomal DNA (rDNA) sequences of the new species are assembled and annotated. The plastid genome is 150,398 bp in length and comprises two inverted repeats (IRs) of 24,688 bp separated by a large single-copy of 83,919 bp and a small single-copy of 17,103 bp. A total of 113 functional genes are recovered, comprising 79 protein-coding genes, 30 tRNA genes, and four rRNA genes. The rDNA is 5,804 bp in length and comprised the 18S ribosomal RNA partial sequence (1,809 bp), internal transcribed spacer 1 (213 bp), 5.8S ribosomal RNA (164 bp), internal transcribed spacer 2 (248 bp) and 26S ribosomal RNA partial sequence (3,370 bp). In addition, the chromosome number of E. qinzhouense is observed to be 2n = 26, suggesting that the species is diploid. Given a consistent relationship between ploidy level and reproductive system in Elatostema, the new species is also considered to be sexually reproducing. Our assessment of the extinction threat for E. qinzhouense is that it is Endangered (EN) according to the criteria of the International Union for Conservation of Nature

Evolution of reaction mechanism in the catalytic combustion of ammonia on copper-cerium mixed oxide

Carbon-free hydrogen-rich ammonia (NH3) is a potential next energy generation source, where a high ignition point and high nitric oxide contents, thereby limiting further development. This study aims to investigate the mechanism evolution during the catalytic ignition process of high NH3 concentration over copper-cerium catalyst to address the demerits of flame combustion. The phase composition, elemental valence, and active species of the copper-cerium oxide (CuO-CeO2) catalyst are investigated using various characterization techniques. The results indicated that Cu species are mainly present in copper-cerium solid solutions and highly dispersed CuO clusters, providing sufficient Cu sites to adsorb NH3 and abun-dant reactive lattice oxygen. The catalytic ignition triggered a kinetic transition from low-rate to high -rate steady-state. During the induction process, the predominance of the L-H mechanism is implied by the kinetic modeling and transient experiments (low-rate induced phase). Combined with IR spec-troscopy and isotope (18O2)-transient response study, the results indicated that adsorbed NH3 reacted with surface adsorbed oxygen, simultaneously pulling out lattice oxygen to react with adsorbed NH3, confirming the coexistence of L-H and M-K mechanism over CuO-CeO2. The L-H mechanism (18O, con-tribution of adsorbed oxygen) plays a relatively dominant role in the induction stage, while the involve-ment of the M-K mechanism (16O, contribution of lattice oxygen) is significantly increased in the sustained combustion stage. At both stages, NH and NH2 served as critical species for N2 generation (i-SCR), respectively, playing an important role in N2 selectivity. Moreover, in the self-sustained combustion stage for CuO-CeO2 (14%NH3), the rapid gas diffusion and mass transfer facilitated the adsorption and activation of NH3. These results are envisaged to provide theoretical support for the handling and appli-cation of high concentrations of NH3.& COPY; 2023 Elsevier Inc. All rights reserved

Quantification of Regional Ozone Pollution Characteristics and Its Temporal Evolution: Insights from Identification of the Impacts of Meteorological Conditions and Emissions

Ozone (O3) pollution has become the major new challenge after the suppression of PM2.5 to levels below the standard for the Pearl River Delta (PRD). O3 can be transported between nearby stations due to its longevity, leading stations with a similar concentration in a state of aggregation, which is an alleged regional issue. Investigations in such regional characteristics were rarely involved ever. In this study, the aggregation (reflected by the global Moran’s I index, GM), its temporal evolution, and the impacts from meteorological conditions and both local (i.e., produced within the PRD) and non-local (i.e., transported from outside the PRD) contributions were explored by spatial analysis and statistical modeling based on observation data. The results from 2007 to 2018 showed that the GM was positive overall, implying that the monitoring stations were surrounded by stations with similar ozone levels, especially during ozone seasons. State of aggregation was reinforced from 2007 to 2012, and remained stable thereafter. Further investigations revealed that GM values were independent of meteorological conditions, while closely related to local and non-local contributions, and its temporal variations were driven only by local contributions. Then, the correlation (R2) between O3 and meteorology was identified. Result demonstrated that the westerly belonged to temperature (T) and surface solar radiation (SSR) sensitive regions and the correlation between ozone and the two became intense with time. Relative humidity (RH) showed a negative correlation with ozone in most areas and periods, whereas correlations with u and v were positive for northerly winds and negative for southerly winds. Two important key points of such investigation are that, firstly, we defined the features of ozone pollution by characterizing the temporal variations in spatial discrepancies among all stations, secondly, we highlighted the significance of subregional cooperation within the PRD and regional cooperation with external environmental organizations

Non-invasively identifying candidates of active surveillance for prostate cancer using magnetic resonance imaging radiomics

Abstract Active surveillance (AS) is the primary strategy for managing patients with low or favorable-intermediate risk prostate cancer (PCa). Identifying patients who may benefit from AS relies on unpleasant prostate biopsies, which entail the risk of bleeding and infection. In the current study, we aimed to develop a radiomics model based on prostate magnetic resonance images to identify AS candidates non-invasively. A total of 956 PCa patients with complete biopsy reports from six hospitals were included in the current multicenter retrospective study. The National Comprehensive Cancer Network (NCCN) guidelines were used as reference standards to determine the AS candidacy. To discriminate between AS and non-AS candidates, five radiomics models (i.e., eXtreme Gradient Boosting (XGBoost) AS classifier (XGB-AS), logistic regression (LR) AS classifier, random forest (RF) AS classifier, adaptive boosting (AdaBoost) AS classifier, and decision tree (DT) AS classifier) were developed and externally validated using a three-fold cross-center validation based on five classifiers: XGBoost, LR, RF, AdaBoost, and DT. Area under the receiver operating characteristic curve (AUC), accuracy (ACC), sensitivity (SEN), and specificity (SPE) were calculated to evaluate the performance of these models. XGB-AS exhibited an average of AUC of 0.803, ACC of 0.693, SEN of 0.668, and SPE of 0.841, showing a better comprehensive performance than those of the other included radiomic models. Additionally, the XGB-AS model also presented a promising performance for identifying AS candidates from the intermediate-risk cases and the ambiguous cases with diagnostic discordance between the NCCN guidelines and the Prostate Imaging-Reporting and Data System assessment. These results suggest that the XGB-AS model has the potential to help identify patients who are suitable for AS and allow non-invasive monitoring of patients on AS, thereby reducing the number of annual biopsies and the associated risks of bleeding and infection

Additional file 1: of Autologous cytokine-induced killer cell transfusion increases overall survival in advanced pancreatic cancer

Demographic and clinical characteristics of individual patient in chemotherapy group. (DOC 85 kb