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This global lockdown of educational institutions by COVID-19 has caused overwhelming disruption in students' learning and assessment, which has substantial effects on their academic emotions. This study applied a mixed methods approach to investigate how COVID-19 influences Gaokao applicants' academic emotions in the Chinese context. The study found that Gaokao applicants during the COVID-19 pandemic had strong positive activating emotions, positive deactivating emotions, and negative activating emotions. The results showed that there were significant gender differences in academic emotions, and students' physical exercise was also related. This study found that there was no correlation between the Gaokao applicants' academic emotions and their parents' occupations, parents' academic qualifications, or types of exams. As COVID-19 continues to be a worldwide public challenge, this study has implications on how to alleviate negative academic emotions of students who will take high-risk tests under the pressure of the pandemic.

This paper reports a study investigating business English teachers' belief about online assessment using Q methodology. To address the common practice that teachers had to conduct online assessment during COVID-19 period and with performance assessment as theoretical foundation, this paper studied 22 Chinese business English teachers' belief when they had to do assessment in online context. With data analysis from Q-methodology and complementary interviews, the findings of this study showed a shared configuration among the business English teachers in three factors: strong belief in performance assessment for business English courses; belief in supportive role of ICT; and belief in assessment as an ongoing process. The three factors were further interpreted from systematic approach of assessment and the role of ICT in online teaching. This study will be of significance to help teachers improve the quality of online assessment and raise their awareness of effective use ICT in online teaching.

While pedagogical content knowledge (PCK) has been studied across a wide range of research areas, including science, language teaching and mathematics, there is limited research on the role of PCK in business English (BE) teaching, an important teaching area of English for Specific Purposes. Informed by the conceptual framework of the PCK model for BE teaching, this study examined how four BE teachers integrated the PCK components in their actual classroom teaching in the English as a Foreign Language (EFL) context in China. The analysis of multiple sources of data including classroom observation, semi-structured interviews and teaching materials, identified the different patterns and ways in which the four PCK components (i.e. knowledge of the purposes of BE teaching, knowledge of instructional strategies for BE teaching, knowledge of students' understanding of BE, and knowledge of the BE curriculum) functioned and were integrated in BE teaching. Implications for BE teaching practice and suggestions for future research on PCK in BE teaching are presented in the paper.

The nitrogen application rate (NAR) has a significant effect on the contents of wheat grain protein and its composition. There is still no consensus regarding the appropriate NAR, given the differences in studied conditions and influence of factors such as geographical location, climate, and soil nutrient contents. In this study, 66 papers related to wheat grain protein and its composition published from 1984 to 2021 were selected for meta-analysis in comprehensively evaluating the response of wheat grain protein content and composition to NAR in China. The results reveal that NAR significantly increased total protein content by 9.49–28.6%, gliadin by 9.13–30.5%, glutenin by 12.9–45.4%, albumin by 5.06–15.8%, and globulin by 8.52–24.0% of wheat grain in China, respectively, compared to no nitrogen application. The optimal NAR is 240–300 kg ha−1 when specific planting conditions are not being considered. Under different growing conditions, the NAR that provided the greatest increase in wheat grain protein and its composition varied as follows: 180–240 kg ha−1 in Northwest China and at >100 m altitudes; >300 kg ha−1 in North China and at <100 m altitudes and lower soil base nutrient levels; 240–300 kg ha−1 in Southeast China, with higher soil nutrients levels and for all average annual temperatures and precipitation ranges. In conclusion, the results of the present study reveal that it is feasible to systematically enhance the contents of wheat grain protein and its related fractions by appropriate NAR under different cropping conditions. [ABSTRACT FROM AUTHOR]

To clarify the species of uranium and its effect on the safety assessment in the disposal of high-level radioactive wastes (HLWs), we presented geochemical simulations of Beishan deep groundwater in Gansu Province, China. The Ca–UO2–CO3 complexes are the main species. They can decrease the blocking of granites on uranium, which is unfavorable for the long-term and safe disposal of HLWs. The Ca2+ may become the critical factor that determines the uranium species when the formation of Ca2UO2(CO3)3(aq) increases with Ca2+ concentrations. Our study provides an important basis and reference for future safety assessment in the geological disposal of HLWs. [ABSTRACT FROM AUTHOR]

Deep fertilization is a beneficial approach for reducing nitrogen losses. However, the effects of various fertilization depths on maize (Zea mays L.) productivity and environmental footprints have not been thoroughly understood. Therefore, a field experiment was conducted to investigate the effects of different fertilization depths of 5 cm (D5), 15 cm (D15), 25 cm (D25), and 35 cm (D35) on maize productivity and environmental footprints. Reactive nitrogen (Nr) losses and greenhouse gas (GHG) emissions were assessed using life cycle analysis. We hypothesized that deep fertilization can obtain lower carbon and nitrogen footprint. The results indicated that deep fertilization decreased the N2O and NH3 emissions while increasing the CH4 uptake. Compared with D5, D15 resulted in an increase in total GHG emissions and carbon footprint (CF), whereas D25 decreased by 13.0% and 23.6%, respectively. Compared with D5, the Nr losses under D15, D25, and D35 conditions was reduced by 11.3%, 17.3%, and 21.0%, respectively, and the nitrogen footprint (NF) was reduced by 16.0%, 27.4%, and 19.0%, respectively. The maize yield under D15 and D25 increased by 5.7% and 13.8%, respectively, compared with the D5 treatment, and the net economic benefits of the ecosystem increased by 7.1% and 17.1%, respectively. In summary, applying fertilizer at a depth of 25 cm can significantly reduce the environmental footprints and increase maize productivity, making it an effective fertilization strategy in the Loess Plateau region of China. [ABSTRACT FROM AUTHOR]

Objective: Human papillomavirus (HPV) integration is a crucial genetic step in cervical carcinogenesis. This study aimed to evaluate the performance of an HPV integration test for the triage of HPV‐positive women. Design: An observational cohort study. Setting: A cervical cancer screening programme in China. Population: 1393 HPV‐positive women aged 25–65 years undergoing routine cervical cancer screening and HPV integration testing with 1‐year follow‐up. Methods: The sensitivity, specificity, positive predictive value and negative predictive value between HPV integration and cytology were compared. Main outcome measures: Cervical intraepithelial neoplasia grade 3 or more severe (CIN3+). Results: Among 1393 HPV‐positive patients, 138 (9.9% [8.3–11.5%]) were HPV integration test positive compared with 537 who had abnormal cervical cytology (38.5% [36.0–41.1%]). Compared with cytology, HPV integration exhibited higher specificity (94.5% [93.3–95.8%] versus 63.8% [61.2–66.4%]) and equivalent sensitivity (70.5% [61.4–79.7%] versus 70.5% [61.4–79.7%]) for detection of CIN3+. HPV integration‐negative women accounted for 90.1% (1255/1393) of the total population and had a low immediate CIN3+ risk (2.2%). At 1‐year follow‐up, the progression rate in the HPV integration‐positive women was higher than in the HPV integration‐negative women (12.0% versus 2.1%, odds ratio 5.6, 95% CI, 2.6–11.9). In 10 conservatively managed integration‐negative CIN2 patients, all showed spontaneous regression and seven showed HPV clearance after 1‐year follow‐up. Conclusion: The HPV integration test may be a precise risk stratification tool for HPV‐positive women and could avoid excessive use of invasive biopsies. [ABSTRACT FROM AUTHOR]

The Yellow River Delta (YRD) is an important agricultural and industrial region in China, yet its water resources have been increasingly affected by shortages and pollution due to human activities and the impact of climate change. This has resulted in severe damage to the water ecosystem in the YRD, thereby necessitating the adoption of effective legal measures to safeguard these resources. This paper provides a comprehensive review of recent research findings on water resources and water ecology in the YRD. Specifically, it summarizes the changes and characteristics of the geographical distribution, quantity and quality of water resources in the region and analyzes the effects of climate change, economic development and population growth on water resources. In light of the vulnerability and risks to the water resources and ecosystems in this area, this paper evaluates the impact of human activities on regional water security and proposes strategies for the sustainable utilization of water resources and the protection of public health. The insights and measures presented in this paper provide valuable guidance and references for water resource management and environmental protection in the YRD. [ABSTRACT FROM AUTHOR]

Informed by literature on developing pedagogical content knowledge (PCK) through teacher collaboration, this study aims to investigate the trajectory of PCK development among business English teachers through module team collaboration in Chinese context. Drawing upon multiple sources of data including observation, semi-structured interview, and teaching materials from three case teachers, this study explores how PCK components were developed in one academic year when case teachers participated in module team collaborative activities. The findings show the individual differences among the three participants in their PCK development and reveal that two key PCK components--Knowledge of students' understanding and Knowledge of instructional strategies have developed through teacher collaboration. This study suggests the collective inquiry in teacher collaboration.

Information regarding regional arterial stiffness assessment in osteoarthritis (OA) was scarce and sometimes contradictory. We aimed to investigate the aortic, lower limb peripheral arterial stiffness and their associations with knee OA. Patients with primary knee OA and matched non-OA controls were prospectively enrolled from two medical centers in China. The carotid-femoral pulse wave velocity (cfPWV) and femoral-ankle pulse wave velocity (faPWV) were measured using a novel ultrasound technique. A total of 238 participants (including 128 patients with knee OA and 110 controls) were included. In OA patients, cfPWV was significantly higher than that of non-OA controls (9.40 ± 1.92 vs 8.25 ± 1.26 m/s, P < 0.0001). However, faPWV measurements in OA patients (12.10 ± 2.09 m/s) showed no significant difference compared with that of the controls (11.67 ± 2.52 m/s, P = 0.130). Multiple regression analysis revealed that cfPWV was independently associated with knee OA (P < 0.0001) after adjusting for the confounding factors including age, gender, smoking, mean blood pressure, body mass index, heart rate, high-sensitivity C-reactive protein and lipids profiles. In contrast, faPWV did not show independent association with knee OA (P = 0.372) when after adjusting for confounding factors. In addition, Spearman's correlation analysis showed cfPWV had a significant correlation with Kellgren-Lawrence score (rs = 0.2333, P = 0.008), but no correlation was founded between faPWV with Kellgren-Lawrence score (rs = 0.1624, P = 0.067) in OA patients. This study demonstrated that stiffening of aorta, but not lower limb arteries, was independently associated with knee OA. Our findings may call for further implementation of routine aortic stiffness assessments so as to evaluate cardiovascular risk in patients with OA. [ABSTRACT FROM AUTHOR]

Rock weathering, an important geological process on the earth's surface, plays a key role in shaping surface morphology, providing nutrients needed by the ecosystem, and regulating the global climate. However, the regimes for controlling rock weathering in different regions are still controversial. In this respect, the heavy minerals, elements, Sr-Nd isotope, magnetic susceptibility, and chromaticity of the granite weathering profile in Harbin, a high latitude area of China, were analyzed for understanding the weathering characteristics and mechanisms of the granite weathering profile in the cold area. The results indicate that the profile underwent strengthened physical weathering (large volumes of cracks in the granite parent rock) and low–moderate chemical weathering (CIA = 56~68). However, the chemical weathering does not clearly affect the composition of the weathering products, making the weathering products a good inheritance from the parent rocks, as evidenced by the binary diagram (e.g., TiO2-Zr, and La/Sc-Co/Th) and geochemical genes (LG01 and LG03). The development process of the weathering profile has been affected by the input of external materials and biological activities, as evidenced by the Sr-Nd isotopic composition, Th/Zr values, chemical depletion fractions, ΔAl/Ti ratios, χfd%, and geochemical genes (LG03). Notably, a progressively decreasing weathering degree with a reduced depth is observed in the profile, which is likely to be related to an addition of external materials and/or effects of biological activities. In addition, the weathering regime of the profile does not vary in geology time, characterized by a kinetic-limited weathering regime with a limited supply. [ABSTRACT FROM AUTHOR]

Carbonisation is one of the important methods to improve the utilisation of coal. The structural composition of coal plays an important role in coal carbonisation. This work used small-angle X-ray scattering (SAXS) to investigate the pore structure of three kinds of raw coals with different carbon content derived from Xingtai City, Hebei Province, China. The structures of the corresponding cokes obtained through carbonisation at 1200°C were investigated by elemental analysis and SAXS. In addition, the gasification reaction of the three cokes (C1, C2, C3) with CO2 were studied by thermogravimetric analysis. The SAXS results indicate that the surface fractal dimension increases while the pore size decreases, and the pore distribution became wider after carbonisation. In addition, all coals and cokes present a positive deviation from Porod's law, indicating that there is a micro-fluctuation of electron density in the samples. Besides, it exhibites a negative correlation has been found between the degree of deviation from Porod's law and the carbon content. The gasification reactivity of cokes C1 and C3 in CO2 are higher than that of C2, indicating that the pore structures affect the gas reactivity of the three different metamorphic degree cokes in CO2. [ABSTRACT FROM AUTHOR]

Under the control of the Montreal Protocol and its amendments, hydrofluorocarbons (HCFCs) are used as temporary substitutes for ozone-depleting substances, such as chlorofluorocarbons, and are regulated for consumption and production. China plans to phase out HCFCs by 2030, and HCFC-22 (CHClF2) is currently the most abundant HCFC in the atmosphere. This study measures the vertical profiles and total columns of atmospheric HCFC-22 from January 2017 to December 2022, based on the mid-infrared solar spectra recorded by the ground-based high-resolution Fourier transform infrared (FTIR) spectrometer at the Hefei remote sensing station. The HCFC-22 total columns over Hefei increased from 2017–2018 and gradually decreased in 2018–2022, with an annual variation rate of 5.98% and −1.02% ± 0.02%, respectively. Compared with the ACE-FTS satellite independent dataset, the FTIR data indicate good consistency with the ACE-FTS data at a 5–25 km altitude, with an average relative difference of −4.38 ± 0.83% between the vertical profiles. HCFC-22 emissions in the Yangtze River Delta from 2017 to 2022 are estimated, derived from measured total columns combined with the Lagrangian transport model and the Bayesian inversion technique. In the Yangtze River Delta, HCFC-22 emissions were high in 2017, with a value of 33.3 ± 16.8 kt, and decreased from 2018 to 2022, with a minimum of 27.3 ± 13.6 kt in 2022 during the observations. [ABSTRACT FROM AUTHOR]

The provenance and aeolian–fluvial interaction are essential for understanding the formation and evolution of sandy land. However, the dune sediment source in the Horqin Sandy Land (HQSL), the largest semi‐stable sandy land in China, has been debated. Here, we collected 900 coarse (i.e., >63 μm) and 750 fine (i.e., <63 μm) detrital zircon (DZ) grains from surface sand in different spatial locations for U–Pb age analysis. The visual comparison largely shows remarkably similar zircon age characteristics throughout the HQSL, and the quantitative results of the inverse Monte Carlo modelling show the primary detrital contribution of the Central Asian orogenic belt (~50.5%–61.3%) to the HQSL. In contrast, the southeast of the HQSL is characterized by the absolute dominance of the North China Craton (~75.8%). The DZ age spectra in the western and northern HQSL are extremely similar but significantly different from the south, indicating the spatial heterogeneity of the HQSL. The DZ ages are largely unaffected by particle size sorting, except in the southeastern HQSL (e.g., the dramatically different detrital contribution of the North China Craton to the fine [52.4%] and coarse fractions [75.8%]). We argue that the aeolian–fluvial interaction and the resulting sedimentary sorting and recycling are responsible for the DZ age characteristics of the HQSL. We confirm that the DZ ages of the HQSL are a faithful record of the tectonic‐magmatic events, for example, the North China Craton massif collision and collusion, the Paleo‐Asian Ocean subduction and closure, the Mongolian‐Okhotsk Ocean plate subduction and the paleo‐Pacific Ocean subduction and retreat. Finally, this study suggests that caution must be exercised in interpreting the paleoclimatic record and the aeolian deposit source investigations due to the spatial heterogeneity and the complex wind‐fluvial interactions in the HQSL. [ABSTRACT FROM AUTHOR]

Competitive strategy plays an important role in achieving superior profits, but there is still much to be explored in terms of the effect on firm growth. This study focuses on exploring the relationship between competitive strategy and firm growth in emerging economies. We focus on how the development zone policies moderate this relationship. This study uses a two-way fixed-effect model to analyze data for 527 manufacturing firms listed in China's Shanghai and Shenzhen A-shares from 2012-2021. Our empirical analysis showed that there is a significant positive relationship between low-cost strategy and firm growth and a significant negative relationship between differentiation strategy and firm growth. Compared with national development zones, firms in provincial development zones choose low-cost strategies that are more conducive to growth. Compared with provincial development zones, firms in national development zones choose differentiation strategies that are more conducive to growth. These findings contribute to understanding the mechanisms by which competitive strategy affects firm growth in different regional institutional contexts in emerging economies. The results of the study also have reference value for the government to optimize the development zone policies. [ABSTRACT FROM AUTHOR]

The Dahai Pb-Zn mining area is located in the northwestern Pb-Zn district in northeastern Yunnan Province in the Sichuan-Yunnan-Guizhou Pb-Zn metallogenic triangle (SYGT), east of the Xiaojiang fault. Numerous Pb-Zn deposits (spots) occur in clastic rocks in this area. In this study, the Maliping, Laoyingqing, and Jinniuchang Pb-Zn deposits, representative clastic rocks in the Dahai mining area, were selected as research objects. The results of H-O-S-Sr-Pb isotope analyses show that the three deposits mainly formed through the mixing of a basinal brine with a hydrothermal fluid derived from deep within the underlying (deformed) basement, and brines leached organic matter from wall rocks. The δ34S values range from −2.62–30.30‰. The S isotope results show two different sources of reduced S: one in the Laoyingqing deposit derived from the S reduction generated by the pyrolysis of sulfur-bearing organic matter in the carbonaceous slate of the Kunyang Group, and the second in the Maliping and Jinniuchang deposits derived from the S reduction generated by the thermochemical sulfur reduction (TSR) of seawater sulfate in the Lower Cambrian Yuhucun Formation and Sinian Dengying Formation. The Pb isotope results show that the Pb sources of the three deposits are derived from basement rocks (Kunyang Group) with a small portion derived from Devonian–Permian carbonate rocks and Dengying Formation dolomite, both of which have undergone homogenization during mineralization. The Sr content varied from 0.09629 to 0.2523 × 10−6, and the study shows that the main source of Sr is a mixture of ore-forming fluid flowing through basement rocks (Kunyang Group) and through sedimentary cover. However, most of the Sr in the Maliping deposit is derived from marine carbonate, and in the Laoyingqing deposit, it is provided by basement rocks (Kunyang Group). Based on a comparative study of the deposits, the Pb-Zn deposits in the clastic rocks of the Dahai mining area and the SYGT belong to the same metallogenic system and were formed under the same metallogenic geological background. Finally, a unified metallogenic model of the two types of fluid migration and mixed mineralization of the Pb-Zn deposit in clastic rocks of the Dahai mining area is proposed. The metallogenic model provides a basis for the study of the Pb-Zn metallogenic system and guidance for deep and peripheral prospecting in this area. [ABSTRACT FROM AUTHOR]

Within the theoretical framework of Pragma-Dialectics, this research investigates prototypical argumentative patterns based on pragmatic argumentation that manifest themselves in the spokespersons' argumentative replies at the regular press conferences of China's Ministry of Foreign Affairs. As is shown by the research results, constrained by the institutional point of the communicative activity type (justifying China's attitude and actions regarding controversial issues) and its institutional preconditions, argumentative patterns based on pragmatic argumentation prototypically occur in three variants, viz. the 'solvency type', the 'maintenance type', and the 'counter-plan type'; it can be observed that in complex pragmatic argumentation each of these three variants may also occur in combination with other variants. [ABSTRACT FROM AUTHOR]

Little is known about the association between surface water quality and cancer incidence, especially in China. Drinking water quality has been linked to the incidence of several cancers in individual-level studies. However, few studies have attempted to examine multiple pollutants and multiple cancers at population level. This study used water monitoring and population-level cancer data from across China to examine spatial associations between water pollutants and types of cancer. We found a "dose–response" relationship between the number of pollutants present at high levels and cancer incidence. These results provide evidence of a nationwide spatial association between water quality and cancer in China. The precise relationship varies with cancers and pollutants. However, the overall consistency of the "dose–response" relationship suggests that surface water quality is an important factor in cancer incidence. Our findings highlight new issues such as the changing effects when different pollutants co-exist and an increasing number of new cancer cases partially attributable to poor water quality. Our work also points to some ways to deal with these challenges. [ABSTRACT FROM AUTHOR]

The accumulation of soda residue (SR) poses a consequential threat to the environment because of the absence of effective methods for treating them on a large scale. SR is composed of NaCl, CaSO4·0.5H2O, and Ca(OH)2 in addition to CaCO3, which can be potentially used to replace reagent-grade alkaline activators for activating furnace slag (FS). This work investigates the effect of SR addition on the hydration mechanism of FS by preparing geopolymer from FS and SR. The geopolymer's compressive strength, initial pH value, and hydration products (including yield and morphology) were analyzed; its activity index was also investigated. The analysis results show that the pozzolanic activity of FS was stimulated using SR as alkaline activator. In the presence of SR, FS dissociated to form [SiO4]4− and [Al2O4]2− first. Then, it reacted with Ca2+, OH−, Na+, Cl−, and SO2 − 4 to form lamellar C(N)–S–H, needle AFt, and platelet Fs. Upon the addition of 70 wt.% SR to 30 wt.% FS, the hydration products reach the highest yield, leading to optimum compressive strengths of 3.43 and 8.84 MPa at 2 and 30 d, respectively. Furthermore, although the activity index of the geopolymer prepared from 70 wt.% SR and 30 wt.% FS is only 50.95%, 0–20 wt.% geopolymer can be used as an additive to prepare a 32.5-grade composite cement. This work realized the large-scale resource management of continuously discharged SR in support of China's double carbon policy. [ABSTRACT FROM AUTHOR]

Carbon dioxide capture, utilization, and storage (CCUS) technology is an emerging technology with large-scale emission reduction potential and an essential component of the global response to climate change to achieve net-zero goals. As the two most important countries in global climate governance, it is necessary to review and examine the current status and trends of research in the field of CCUS in China and the USA. This paper uses bibliometric tools to review and analyze peer-reviewed articles in the Web of Science from both countries during 2000–2022. The results show a significant increase in research interest among scholars from both countries. The number of publications in the CCUS field in China and the USA was 1196 and 1302, respectively, showing an increasing trend. China and the USA have become the most influential countries in CCUS. And the USA has a more significant academic influence on a global scale. Furthermore, the research hotspots in the field of CCUS are diverse and differentiated. That is, China and the USA pay attention to different research hotspots or have different focuses in different periods. This paper also finds that new capture materials and technology development, geological storage monitoring and early warning, CO2 utilization and new energy development, sustainable business models, incentive policies and measures, and public awareness are critical directions for future research in the field of CCUS, to provide a comprehensive review and comparison of CCUS technology development in China and the USA. It helps to gain insight into the research differences and linkages between the two countries in the field of CCUS and identify the research gaps between them. And place some consensus that policymakers can use. [ABSTRACT FROM AUTHOR]

Chinese coal enterprises are facing severe challenges due to low-carbon economy requirements and capacity reductions. This paper adopts a dynamic SBM model to compare the mining efficiency of each mining area of a coal company in China. We use total excavation footage, number of working platforms, and machine quantities as input indicators, and coal sales and CO2 emissions as output indicators. It was found that (1) both high efficiency and low efficiency mines maintained their production status each year and did not actively improve over time; (2) energy consumption was the primary indicator affecting comprehensive mining efficiency; and (3) while changes in the market environment did not have any significant impact on coal mining efficiency, coal mine characteristics were found to have some correlations with efficiency. [ABSTRACT FROM AUTHOR]

The generation time distribution, reflecting the time between successive infections in transmission chains, is a key epidemiological parameter for describing COVID-19 transmission dynamics. However, because exact infection times are rarely known, it is often approximated by the serial interval distribution. This approximation holds under the assumption that infectors and infectees share the same incubation period distribution, which may not always be true. We estimated incubation period and serial interval distributions using 629 transmission pairs reconstructed by investigating 2989 confirmed cases in China in January-February 2020, and developed an inferential framework to estimate the generation time distribution that accounts for variation over time due to changes in epidemiology, sampling biases and public health and social measures. We identified substantial reductions over time in the serial interval and generation time distributions. Our proposed method provides more reliable estimation of the temporal variation in the generation time distribution, improving assessment of transmission dynamics. The generation time (interval between successive infections in a transmission chain) is an important parameter for epidemiological modeling. Here, the authors develop a framework for estimating this parameter and how it changes over time and apply it to data from China in the first months of the pandemic. [ABSTRACT FROM AUTHOR]

Southwest China is distributed with the largest area of limestone and dolomite karst landscapes in the world, and its ecological environment is very fragile; the problem of rock desertification is particularly prominent. Karst lithological differences make habitats and soil heterogeneity more complex, and vegetation has developed certain morphological and physiological structural characteristics to adapt to these special environments, which will most likely lead to differentiation in vegetation functional characteristics, such as seed size, wood density, life type and flowering time, thus affecting the number and growth of seedlings and young trees and the future succession potential of forest stands in karst-vegetation restoration. Therefore, it is important to understand the differences in species composition and the functional characteristics of dolomite and limestone karst forests. Over a 2-year period, we investigated a total of 3170 individuals from 123 species and analyzed the relationship between the species compositions and the functional characteristics of two karst-forest areas with different lithology (i.e., limestone and dolomite karst). It was found that the average number of species with medium-diameter seeds and medium wood density in dolomite plots was obviously greater than the average number of species in limestone plots, but this reached no significant difference. However, with the gradual restoration of each forest, the height and carbon sequestration capacity of the trees began to diverge, with the relative abundance of species with tall trees and high wood density being significantly higher in limestone plots than in dolomite plots. The species richness of evergreen trees was significantly higher in the limestone plots than in the dolomite plots. There was no significant difference in the relative species richness of flowering plants in the two karst-forest areas during spring–summer and winter–spring seasons; however, the species richness of flowering plants in the limestone karst forests was significantly higher than that of flowering plants in the dolomite karst forests during summer and autumn seasons. These significant traits were very closely related to the species richness of the understory plants. Further insight into the temporal aspects of karst-forest succession is needed to grasp how functional traits affect the restorations of different lithological karst forests to their primary states. [ABSTRACT FROM AUTHOR]

China's BeiDou navigation system has been completed and is currently in operation. As the newest constellation, BD-3 is composed of 30 satellite configurations. The application of BD-3 has improved rapidly, however, using the BD-3 signal as a signal resource in the global navigation satellite system (GNSS) passive radar domain to monitor deformation has not been proven to be feasible. The authors of his paper designed a BD-3 passive radar model and carried out a proof-of-concept experimental demonstration for deformation monitoring. As a result, a method based on the B3I signal as a signal resource for GNSS radar (GNSS-R) deformation monitoring is proven to be feasible. The experimental scenarios include laboratory simulation and proof of concept field displacement deformation. The test error reaches a value of 0.023 m for a simulation scenario, 0.0435 m for a field scene of deformation based on a target translation measurement, and 0.1011 m for a field scene of deformation based on a target rotation measurement. [ABSTRACT FROM AUTHOR]

Simple Summary: The mangrove ecosystem is an important resource for the survival of thousands of species of animals and plants. It has high ecological and economic value and has made great contributions to the protection and maintenance of marine and terrestrial ecological environment. However, due to climatic and human factors, the mangrove ecosystem has been destroyed and its ecological functions have been damaged. As an important indicator species, fishes have also been affected, with changes in their population and nutritional structure. This study summarized the mangrove fish in China and compiled a relatively complete list of mangrove fish. In addition, the biogeographic characteristics of Chinese mangrove fish were analyzed, filling the gap of national mangrove fish distribution data. Completion of this study contributed to a better understanding of the role of mangroves in maintaining the stability and diversity of fish communities, which was of great value for the management and conservation of regional and global biodiversity. Mangroves are among the most productive marine and coastal ecosystems and play an important role in maintaining the stability and diversity of fish communities. To explore the structure of mangrove fish communities in China, we compiled previous studies, monographs, and two databases on 54 mangrove areas published in the past 30 years. Mangrove fish communities in China comprised Osteichthys (597 species) and Chondrichthyes (14 species), representing 611 species in 344 genera, 117 families, and 28 orders. Perciformes were the predominant taxon, with 350 species in 52 families, accounting for 57% of the total species richness. Reef fish accounted for 29.62%. With regard to feeding groups, there were 328 carnivorous species (53.68%), 214 omnivorous species (35.02%), 41 herbivorous species (6.71%), and 28 detritivores species (4.58%). Classified by body size, 57.61% were small-sized, 24.22% medium-sized, and 18.17% were large-sized fishes. A total of 5.23% (32 species) of these mangrove fish are currently on IUCN red lists, i.e., 2 species are critically endangered, 4 are endangered, 12 are vulnerable, and 14 are near threatened. Cluster analyses shows that Chinese mangroves fish were divided into two categories, i.e., coastal mangrove and island mangrove type. This is closely related to the distribution of reef fish. Moreover, the number of fish species showed a strong positive correlation with mangrove area, but not with latitude. The main reasons may be the subtropical and tropical geographic locations, as well as the characteristics of the South China Sea and the Taiwan Warm Current. The size and integrity of mangrove area are crucial to the local ecosystems; thus, protecting and restoring mangroves is of great significance to large-scale ecosystem-stability and local biodiversity. [ABSTRACT FROM AUTHOR]

In this paper, to investigate the synthetic effect of PrEP (pre‐exposure prophylaxis) and ART (antiretrovial therapy) on HIV transmission among MSM (men who have sex with men) in heterogenous environment, a realistic HIV epidemic model with spatial diffusion is established. Here, HIV infectious people are divided into three immunity based compartments, that is, CD4+ T cell count less than 350, between 350 and 500, and more than 500, respectively. The basic reproduction number R0 is established and proved as a threshold parameter: The global asymptotic stability of the disease‐free steady state holds for R0<1, and the disease will be present if R0>1. Considering the substantial advantages of PrEP and ART in controlling HIV transmissions among MSM, the optimal control problem is presented for the case of positive constant diffusion coefficients, which minimize the total population of susceptible individual and HIV infected individual, the cost of PrEP and ART therapy. As an illustration of our theoretical results, we conduct numerical simulations. We also conduct an optimal control case study where model parameters are estimated from the demographic and epidemiological data from China. This work suggests the following: (1) Spatial factors cannot be ignored during the HIV intervention; (2)taking the PrEP intervention measure for HIV transmissions among MSM as early as possible will help to improve the control efficiency and reduces its cost; (3) reducing the PrEP drug costs will promote the efficiency of PrEP treatment in preventing the spread of HIV among MSM. [ABSTRACT FROM AUTHOR]

The Neoproterozoic tectonics of the Yangtze Block is crucial for understanding its evolution history over the assembly and disintegration of the supercontinent Rodinia. Herein, we integrate all the published geochemical and geological data for igneous rocks of 1.0–0.6 Ga from the northern margin of the Yangtze Block to investigate the secular tectonic evolution of the Yangtze Block. The results show that the early Neoproterozoic intra-oceanic subduction could have initiated at ca. 1.0 Ga, which was followed by the flare-up of continental arc magmatism since ∼0.9 Ga along the northern margin of the Yangtze Block. Crustal reworking was enhanced during episodes of subduction compression at ca. 0.86 Ga and 0.83 Ga, respectively, revealed by the striking decrease in zircon ε Hf (t) and whole-rock ε Nd (t) values. The gradual progression to depleted mantle-like isotopic signatures during 850–840 Ma and 820–810 Ma reflects the diminishing subduction-induced enrichment in the mantle source as the tectonic setting altered to the extensional back-arc modes shortly after the compressional phases. The secular isotope pattern during the continental arc stage (0.9-0.8 Ga) implies alternative regimes of compressive and extensional tectonics, which were accompanied with synchronous changes in crust thickness. After ∼0.8 Ga, the northern margin of the Yangtze Block evolved into distinct tectonics in different regions. The 0.8–0.73 Ga magmatism in the northeastern domains displays both within-plate and arc-like geochemical affinities, as well as exclusively low δ18O signatures, suggesting a predominantly continental rift setting. However, the widespread calc-alkaline I-type granitoids and contemporaneous arc-like mafic rocks in the northwestern domains demonstrate that the tectonic regime were still controlled by a continuous subduction process until the end of arc magmatism at ca. 0.73 Ga. Subsequently, the entire northern margin of the Yangtze Block gradually evolved into a volcanic rifted margin during 0.72-0.62 Ga as revealed by the deposition of massive syn-rift volcanic-sedimentary sequences and the emplacement of the contemporaneous mafic-ultramafic equivalents, probably as a response to the far-field effect of supercontinent breakup. Collectively, the prolonged (∼1.0–0.73 Ga) supra-subduction magmatism along the northwestern of the Yangtze Block, together with the 0.97–0.82 Ga accretionary belt along the southeastern margin, likely indicates an external position of the South China Block in Rodinia. • Amalgamation of South China into Rodinia through subduction accretionary orogeny. • Advancing-retreating subduction dynamics control the crustal thickness. • Rifts accompanied with Rodinia breakup superimposed on juvenile continental crust. • The South Qinling was a part of the northern Yangtze Block during Neoproterozoic. • The South China Block was peripheral in Rodinia. [ABSTRACT FROM AUTHOR]

Purpose: The Chinese government has authorized the emergency use of an inactivated vaccine for COVID-19 in children and adolescents aged 3 to 17 years. This study aimed to investigate parents' attitudes towards vaccinating their children against COVID-19 and influencing factors. Patients and Methods: Through an online questionnaire survey, we collected self-reported children's demographic characteristics, physical conditions and parents' attitudes towards COVID-19 vaccination for children. The parents in the unwilling group received online consultation about the benefits and risks of COVID-19 vaccine and were asked to complete the questionnaire again. Results: A total of 868 participants were recruited from July 2021 to August 2021 in Nanjing, China. Overall, 76.0% of parents were willing to accept vaccination for children. Parents' willingness increased with children's age (P=0.018) and height (P=0.034), but decreased if the children fell sick within previous one month (P=0.030). Most of the unwilling parents gave a higher score to the risk of vaccination (53.76 VS 40.18). Unsafety (63.8%) and unfamiliarity (24.0%) were their major concerns. After consultation with a health worker, 24% of the unwilling parents turned willing. Conclusion: Children's age and recent physical condition are related to parents' attitudes towards vaccination for children against COVID-19. The major concerns of parents are unsafety and unfamiliarity. Parents view health workers as a reliable source of vaccine information. A successful consultation with health workers to understand the benefits and risks of vaccination can increase parents' willingness. This study provides insight into parents' attitudes towards vaccination for children against COVID-19 in China and related influencing factors. Our findings could be referenced in establishing policies for vaccinating children against COVID-19 in China. [ABSTRACT FROM AUTHOR]

Using detailed exposure information on COVID-19 cases, we estimated the mean latent period to be 5.5 (95% CI: 5.1–5.9) days, shorter than the mean incubation period (6.9 days). Laboratory testing may allow shorter quarantines since 95% of COVID-19 cases shed virus within 10.6 (95% CI: 9.6–11.6) days of infection. [ABSTRACT FROM AUTHOR]

Innovative fertilizer management is the most effective strategy for increasing crop yields and reducing environmental pollution. Deep fertilization reduces NH 3 emissions and increases crop yield, but its effects on N 2 O emissions are still unclear. Nitrification or urease inhibitors trigger cross-contamination of N 2 O and NH 3. Little is known about whether innovative fertilizer management strategies can reduce nitrogen emissions while maintaining higher yields. We conducted field experiments using maize in the semi-humid and drought-prone areas of the Loess Plateau in China from 2019 to 2021. To further verify the research results, experiments were conducted in semi-arid and drought-prone areas in 2022 and 2023 using surface fertilization (SF), surface fertilization with nitrification (SNI) or urease inhibitor (SUI), deep fertilization (DF), and deep fertilization with urease and nitrification inhibitor (DUN) as experimental treatments. The trends were similar at the three experimental locations over five years, where the ability of DF to reduce emissions was equivalent to those of SNI for N 2 O and SUI for NH 3. However, the increase in the crop productivity was significantly higher under DF than SUI and SNI. Compared with SF, DF significantly reduced the N 2 O and NH 3 emissions by 39.85 % and 46.08 %, respectively, and significantly the increased maize yield, N uptake, and nitrogen use efficiency (NUE) by 16.86 %, 15.83 %, and 32.79 %. The innovative fertilizer management strategies combined the advantages of inhibitors and deep fertilization, and they obtained the highest maize yield and NUE, as well as the lowest N 2 O and NH 3 emissions and gaseous nitrogen loss intensity (GNLI) among all treatments. Compared with SF, DUN reduced the urease, nitrate reductase, nitrite reductase, and hydroxylamine reductase activities by 22.03 %, 58.81 %, 52.72 %, and 50.27 %, respectively, the soil NO 3 –-N and NH 4 +-N contents by 82.94 % and 53.71 %, and N 2 O and NH 3 emissions by 80.79 %, and 79.33 %. DUN increased the maize yield and NUE by 23.30 % and 46.91 %, respectively, and decreased the GNLI by 84.69 %. DUN reduced the concentration of substrates for producing gaseous nitrogen by regulating the activities of soil nitrogen circulating enzymes to significantly reduce the nitrogen loss, and it achieved the highest maize yield (11,818.10 kg ha–1) and NUE (46.62 %) with the lowest GNLI (0.71 g N kg–1 grain). Innovative fertilizer management strategies can help to balance economic and environmental benefits in the Loess Plateau region of China. Our findings provide a reference for obtaining higher maize productivity with low environmental pollution in the Loess Plateau region of China. • Effects of deep fertilization and inhibitors on maize productivity and gaseous nitrogen losses comprehensively evaluated. • Nitrification inhibitor reduced N 2 O emissions but not NH 3 emissions. • Urease inhibitor reduced both N 2 O and NH 3 emissions. • Deep fertilization reduced N 2 O and NH 3 emissions. • Deep fertilization with inhibitors obtained higher maize productivity with the lower environmental cost. [ABSTRACT FROM AUTHOR]

• Isoalliin was converted into cycloalliin at high temperature by addition reaction. • Water containing 3% formic acid could inhibit alliinase activity effectively. • Isoalliin was the most abundant organosulfur compounds in Welsh onion. • Most components were richer in pseudo stem than leaf except for Asp and Cys. • Propiin and Pro were the most important biomarkers between LWJT and ZQ pseudo stem. A reliable, simple, and sensitive method capable of quantifying six organosulfur compounds (OSCs) was established. The samples were extracted by water containing 3 % formic acid with a simple vortex, ultrasound, and centrifugation step, and the solutions were analyzed by ultra-high-performance liquid chromatography separation system coupled with a triple-quadrupole mass spectrometry (UHPLC − MS/MS). Then the method was applied for the analysis of six OSCs in five varieties of two types Welsh onions in China, and the moisture content, reducing sugar, total polyphenols, and 21 free amino acids were also analyzed to study the characters of these Welsh onions intensively. Multivariate statistical analysis was used to investigate the differences in OSCs and free amino acids profiles among the samples. This study showed that enzymatic inhibition method combined with UHPLC − MS/MS is an effective technique to analyze OSCs in Welsh onion, and could be valuable for the routine quantitation of OSCs in other foods. [ABSTRACT FROM AUTHOR]

This paper investigates a new multi-objective order assignment and scheduling problem for personal protective equipment (PPE) production and distribution during the outbreak of epidemics like COVID-19. The objective is to simultaneously minimize the total cost and maximize the PPE supply timeliness. For the problem, we first develop a bi-objective mixed-integer linear program (MILP). Then an $\epsilon $ -constraint combined with logic-based Benders decomposition method is proposed based on some explored properties. We then extend the proposed model to handle dynamics and randomness. In particular, we design a predictive reactive rescheduling approach to address random order arrivals and manufacturer disruptions. Computational experiments on a real case from China and 100 randomly generated instances are conducted. Results show that the proposed algorithm significantly outperforms an adapted $\epsilon $ -constraint method combined with the proposed MILP and the widely used non-dominated sorting genetic (NSGA-II) in obtaining high-quality Pareto solutions. Note to Practitioners—The unprecedented outbreak of COVID-19 and its rapid spread caught numerous national and local governments unprepared. Healthcare systems faced a vital scarcity of PPEs. The urgency of producing and delivering PPEs increases as the number of infected cases rapidly increases. A key challenge in response to the epidemic is effectively and efficiently matching the demands and needs. Performing practical and efficient order assignment and scheduling for PPE production during the COVID-19 outbreak is critical to curbing the COVID-19 pandemic. This work first proposes a bi-objective mixed-integer linear program for optimal order assignment and scheduling for PPE production. The aim is to achieve an economical and timely PPE production and supply. A novel method that combines the $\epsilon $ -constraint framework and the logic-based Benders decomposition is proposed to yield high-quality Pareto solutions for practical-sized problems. Computational results indicate that the proposed approaches are practical and feasible, which can help decision-makers to perform acceptable order assignment and scheduling decisions. [ABSTRACT FROM AUTHOR]

Gandou decoction (GDD) is a classic prescription for the treatment of hepatolenticular degeneration (HLD) in China; however, the liver-protecting mechanism of this prescription needs further evaluation. In the present study, we explored the protective mechanisms of GDD in a copper-laden HLD model using integrated pharmacology and cellular metabolomics in vitro. The results revealed that GDD could significantly promote copper excretion in copper-laden HLD model cells and improve the ultrastructural changes in hepatocytes. In addition, GDD could decrease the extent of lipid peroxidation, levels of reactive oxygen species, and the release rate of lactate dehydrogenase while increasing the activity of superoxide dismutase and the ratio of glutathione to oxidized glutathione in the copper-laden HLD model cells. On conducting statistical analysis of significant metabolic changes, 47 biomarkers and 30 related metabolic pathways were screened as pharmacological reactions induced by GDD in HLD model cells. d-glutamate and d-glutamine metabolic pathways showed the highest importance and significance among the 30 metabolic pathways, and the differential expression levels of the glutamine synthetase (GS) and the renal type and liver type GLS (GLS1 and GLS2) proteins were verified by Western blotting. Collectively, our data established the underlying mechanism of GDD therapy, such as the promotion of copper excretion and improvement in oxidative stress by regulating the expressions of GS, GLS1, and GLS2 protein to protect hepatocytes from injury. [ABSTRACT FROM AUTHOR]

After the successful exploration of marine shale gas, the marine-continental transitional shale gas has gained plenty of attention in China for its great resource potential. However, little work has been finished regarding on the paleoenvironment and organic matter accumulation within shales. Based on element geochemistry, it is concluded that the Upper Paleozoic strata underwent a transition from marine to continental environment but the climate, sedimentary facies, and redox condition did not coevolve synchronously. The organic matter enrichment is controlled by redox condition, not the climate and the Taiyuan Formation, with the highest total organic carbon content, is also favorable for transitional shale gas exploration in the L-Block, eastern Ordos Basin. [ABSTRACT FROM AUTHOR]

To clarify the characteristics and interannual variation of air pollution since the implementation of China's clean air actions, hourly in situ measurements of six gaseous and particulate criteria pollutants at 100 sites in Shandong Province were studied during 2014–2018. General decreasing trends in the concentrations of PM2.5, PM10, NO2, SO2, and CO were observed, while O3 increased continuously. In 2018, the annual average PM2.5, PM10, NO2, SO2, and CO concentration in Shandong was 50, 100, 35, 16 μg m−3, and 1.5 mg m−3, representing decreases of 39%, 30%, 24%, 73%, and 35% from 2014, respectively. These decreases occurred throughout the province. Seven "2 + 26" cities (in Beijing–Tianjin–Hebei and its surrounds) in western Shandong had higher average concentrations and greater reductions than other areas. In contrast, O3 concentration rose, with occurrences of the 90th percentile of all daily maximum 8-h averages increasing by 12% from 159 to 181 μg m−3, during 2014–2018. From May to September, O3 pollution dominated as the sole primary pollutant on non-attainment days, and PM2.5 contributed to more than 90% of polluted days in wintertime months. Population exposures were investigated based on high-resolution monitoring data and population distribution, and high exposure to pollution was displayed. The population-weighted exposure to PM2.5 in Shandong was 50 μg m−3, a decrease of 33%. Eighty-nine percentage of the provincial population was exposed to PM2.5 > 35 μg m−3, while for 99.2% of population in the seven "2 + 26" cities, PM2.5 exposure exceeded 50 μg m−3. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is a chronic and fatal neurodegenerative disease; accumulating evidence suggests that vitamin deficiency is associated with the risk of AD. However, studies attempting to elucidate the relationship between vitamins and AD varied widely.Objective: This study aimed to investigate the relationship between serum vitamin levels and AD in a cohort of the Chinese population.Methods: A total of 368 AD patients and 574 healthy controls were recruited in this study; serum vitamin A, B1, B6, B9, B12, C, D, and E were measured in all participants.Results: Compared with the controls, vitamin B2, B9, B12, D, and E were significantly reduced in AD patients. Lower levels of vitamin B2, B9, B12, D, and E were associated with the risk of AD. After adjusting for age and gender, low levels of vitamin B2, B9, and B12 were still related to the risk of AD. In addition, a negative correlation was determined between vitamin E concentration and Activity of Daily Living Scale score while no significant association was found between serum vitamins and age at onset, disease duration, Mini-Mental State Examination, and Neuropsychiatric Inventory Questionnaire score.Conclusion: We conclude that lower vitamin B2, B9, B12, D, and E might be associated with the risk of AD, especially vitamin B2, B9, and B12. And lower vitamin E might be related to severe ability impairment of daily activities. [ABSTRACT FROM AUTHOR]

Background: Coronavirus disease 2019 (COVID-19) has caused a heavy disease burden globally. The impact of process and timing of data collection on the accuracy of estimation of key epidemiological distributions are unclear. Because infection times are typically unobserved, there are relatively few estimates of generation time distribution.Methods: We developed a statistical framework to jointly estimate generation time and incubation period from human-to-human transmission pairs, accounting for sampling biases. We applied the framework on 80 laboratory-confirmed human-to-human transmission pairs in China. We further inferred the infectiousness profile, serial interval distribution, proportions of presymptomatic transmission, and basic reproduction number (R0) for COVID-19.Results: The estimated mean incubation period was 4.8 days (95% confidence interval [CI], 4.1-5.6), and mean generation time was 5.7 days (95% CI, 4.8-6.5). The estimated R0 based on the estimated generation time was 2.2 (95% CI, 1.9-2.4). A simulation study suggested that our approach could provide unbiased estimates, insensitive to the width of exposure windows.Conclusions: Properly accounting for the timing and process of data collection is critical to have correct estimates of generation time and incubation period. R0 can be biased when it is derived based on serial interval as the proxy of generation time. [ABSTRACT FROM AUTHOR]

Background The relative contributions of asymptomatic, presymptomatic, and symptomatic transmission of severe acute respiratory syndrome coronavirus 2 have not been clearly measured, although control measures may differ in response to the risk of spread posed by different types of cases. Methods We collected detailed information on transmission events and symptom status based on laboratory-confirmed patient data and contact tracing data from 4 provinces and 1 municipality in China. We estimated the variation in risk of transmission over time and the severity of secondary infections by symptomatic status of the infector. Results There were 393 symptomatic index cases with 3136 close contacts and 185 asymptomatic index cases with 1078 close contacts included in the study. The secondary attack rates among close contacts of symptomatic and asymptomatic index cases were 4.1% (128 of 3136) and 1.1% (12 of 1078), respectively, corresponding to a higher transmission risk from symptomatic cases than from asymptomatic cases (odds ratio, 3.79; 95% confidence interval, 2.06–6.95). Approximately 25% (32 of 128) and 50% (6 of 12) of the infected close contacts were asymptomatic from symptomatic and asymptomatic index cases, respectively, while more than one third (38%) of the infections in the close contacts of symptomatic cases were attributable to exposure to the index cases before symptom onset. Conclusions Asymptomatic and presymptomatic transmissions play an important role in spreading infection, although asymptomatic cases pose a lower risk of transmission than symptomatic cases. Early case detection and effective test-and-trace measures are important to reduce transmission. [ABSTRACT FROM AUTHOR]

Purpose: This study explores the influencing factors of smart logistics ecological chain's (SLEC's) organizational collaboration and designs a corresponding conceptual framework. Design/methodology/approach: The multi-case study is applied to this paper. Specifically, this study is a combination of exploratory and explanatory case studies. Findings: The findings are threefold. First, empowerment capability and the information-sharing level are unique factors that affect SLEC's organizational collaboration. Second, greater empowerment capability stimulates the increase of information-sharing level. Third, emerging digital technology, personalized demand and peer competition affect the degree of SLEC's organizational collaboration through an intermediary variable – empowerment capability. Specifically, the emerging digital technology application and peer competition degrees have positive effects on empowerment capability, while the demand personalization degree negatively (positively) affects empowerment capability in the short (long) term. Originality/value: As an important part of supply chain performance, organizational collaboration is receiving more attention. However, in the smart economy context, no theoretical framework exists for analyzing factors that affect the organizational collaboration degree of SLEC. This study fills this gap. [ABSTRACT FROM AUTHOR]

Improvements in grain yield and nitrogen (N)-use efficiency (NUE) are being sought to combat the excessive application of N fertilizer in the rice-wheat rotation system in China. Improving N-uptake efficiency (NUpE) is expected to explore the synergy of grain yield and NUE, but the accumulation and remobilization of N in wheat with high NUpE is still obscure. A 2-year field experiment was conducted to study how to improve NUpE through crop management of planting densities, N application splits, and wheat growth stages when the last N was topdressed. In both years, NUpE was significantly positively related to grain yield and NUE. Comparing with the low and medium NUpE groups (grouping the treatments using cluster analysis of NUpE), the high NUpE group had more total N accumulation as a result of absorbing abundant N from re-greening (Zadoks growth stage, GS25) to anthesis (GS60), and higher N accumulation in grains mainly due to increasing N remobilization from the vegetative organs. Our results indicated that improving the planting density (from 150 to 225 plants m−2) promoted N accumulation before stem elongation (GS30). Late application of more N fertilizers (N application splits 3:1:3:3 versus 5:1:2:2) and relatively early application of the last N portion [topdressing when the flag leaf was visible (GS37) or at booting (GS45) versus topdressing at heading (GS55) or anthesis] boosted N accumulation from stem elongation to anthesis. Finally, a combination of agronomic measures was proposed to achieve high yield and NUE through promoting pre-anthesis N accumulation and NUpE. [ABSTRACT FROM AUTHOR]

Research on tight gas reservoirs in the eastern margin of the Ordos Basin, China, has recently become a hot spot. This paper mainly studies the reservoir characteristics of tight sandstone in the north-central area close to the provenance in eastern Linxing. Cast thin section, scanning electron microscopy, high-pressure mercury injection, and X-ray diffraction (XRD) were applied to discriminate the tight sandstone reservoir differences between the Permian Taiyuan and Shanxi formations in the study area. The results show that the deltaic tight sandstones in the Shanxi Formation are dominated by lithic quartz sandstone and lithic sandstone with an average porosity of 2.3% and permeability of 0.083 mD. The epicontinental tight sandstones in the Taiyuan Formation are mainly lithic sandstone and lithic quartz sandstone, with average porosities and permeabilities of 6.9% and 0.12 mD, respectively. The pore type is dominated by secondary dissolution pores, containing a small number of primary pores, and fractures are not developed. The capillary pressure curves of the Taiyuan Formation sandstone are mainly of low displacement pressure, high mercury saturation, and mercury withdrawal efficiency, while the Shanxi Formation sandstone is mainly of high displacement pressure, low mercury saturation, and withdrawal efficiency. The diagenetic evolution of sandstone in the Shanxi Formation is in meso-diagenesis stage A, and the Taiyuan Formation has entered meso-diagenesis stage B. The siliceous cement in the Taiyuan Formation sandstone enhanced the sandstone resistance to compaction and retained some residual intergranular pores. The pore types in the Shanxi Formation sandstone are all secondary pores, while secondary pores in the Taiyuan Formation sandstone account for approximately 90%. The results can be beneficial for tight gas production in the study area and similar basins. [ABSTRACT FROM AUTHOR]

Background To assess the case fatality risk (CFR) of COVID-19 in mainland China, stratified by region and clinical category, and estimate key time-to-event intervals. Methods We collected individual information and aggregated data on COVID-19 cases from publicly available official sources from 29 December 2019 to 17 April 2020. We accounted for right-censoring to estimate the CFR and explored the risk factors for mortality. We fitted Weibull, gamma, and log-normal distributions to time-to-event data using maximum-likelihood estimation. Results We analyzed 82 719 laboratory-confirmed cases reported in mainland China, including 4632 deaths and 77 029 discharges. The estimated CFR was 5.65% (95% confidence interval [CI], 5.50–5.81%) nationally, with the highest estimate in Wuhan (7.71%) and lowest in provinces outside Hubei (0.86%). The fatality risk among critical patients was 3.6 times that of all patients and 0.8–10.3-fold higher than that of mild-to-severe patients. Older age (odds ratio [OR], 1.14 per year; 95% CI, 1.11–1.16) and being male (OR, 1.83; 95% CI, 1.10–3.04) were risk factors for mortality. The times from symptom onset to first healthcare consultation, to laboratory confirmation, and to hospitalization were consistently longer for deceased patients than for those who recovered. Conclusions Our CFR estimates based on laboratory-confirmed cases ascertained in mainland China suggest that COVID-19 is more severe than the 2009 H1N1 influenza pandemic in hospitalized patients, particularly in Wuhan. Our study provides a comprehensive picture of the severity of the first wave of the pandemic in China. Our estimates can help inform models and the global response to COVID-19. [ABSTRACT FROM AUTHOR]

The pollution of polycyclic aromatic hydrocarbons was serious in sediments of the Pearl River estuary, China. A fluorene-degrading bacterium, strain A2-3, was isolated from hydrocarbon contaminated sediment of this estuary and identified as Rhodococcus sp. based on the analyses of 16S rRNA gene sequence and morphology. Rhodococcus sp. A2-3 can take naphthalene, p-Teropheny, fluorene, pyrene, salicylic acid, citric acid, acetic acid, diethyletheranhydrous, methanol or 4,4′-dibromodiphenyl ether as sole carbon source. 100% of 100 mg/L fluorene or 89% of 400 mg/L fluorene was removed in 7 days by strain A2-3 at 30 °C and pH 7.5. The strain A2-3 showed a high degradation efficiency of fluorene when pH values ranged from 5.5 to 8.5. The proposed pathway of fluorene catabolism by strain A2-3 was initially attacked by 3,4 dioxygenation. Our results suggested Rhodococcus sp. A2-3 can degrade PAHs under aerobic conditions and can function in bioremediation, particularly for weakly acid environment. [ABSTRACT FROM AUTHOR]

A series of tectonic activities induced by the subduction of the Palaeo‐Asian Ocean (PAO) in the Palaeozoic have been recorded in the North China Craton (NCC). Sedimentary strata provide some precious records to reconstruct the basin evolution in the NCC. In this study, we carried out detrital zircon LA‐ICP‐MS U–Pb dating, sandstone modal analysis, bulk‐rock major, and trace elemental measurements for the Sunjiagou and Liujiagou formations in the eastern Ordos Basin to trace the material source. The results show that the sedimentary rocks were mostly sourced from active continental margins. The detrital zircon ages of the Sunjiagou and Liujiagou formations spread from >3,000 to 250 Ma with peaks of main age populations at 2,508, 1,890, 430, and 270 Ma. Based on the age comparison and the southward palaeocurrents, we consider that the source material of these sedimentary rocks comes from the northern margin of the NCC. This in turn indicates that the amalgamation of the PAO and the NCC should have finished at least by the end of the Late Permian. [ABSTRACT FROM AUTHOR]

• The integrated dating strategies constrain the age of the Baitushan Fm. to be 1.1 Ma. • The Baitushan Fm. strata are of a braided river origin under warm/semi-arid climate. • The significant Quaternary uplift of the Great Xing'an Range before at least 1.1 Ma. • The Baitushan Fm. strata reveal that the birth of Yalu River no later than 1.1 Ma. The Songliao Basin plays a key role in determining the basin-mountain evolution history of the China, which is closely related to uplift dynamics, paleoenvironment changes, and landform evolution. Whereas, knowledge of basin-mountain evolution history of landforms in NE China since Quaternary remains limited, due to a lack of high-quality sedimentary records. The Baitushan Formation strata in the western Songliao Basin, are of great significance because they record a series of regional tectonic uplift, volcanism and drainage evolution events. However, the sedimentary environment and age of the strata are still highly controversial, which limits our understanding of the evolutionary history of the basin-orogenic belt systems in the NE China. Here, we present a multidisciplinary approach, e.g., geochronology, sedimentology, petrography, mineralogy and geochemistry, for an investigation of the stratotype section of the Baitushan Formation. The Baitushan Formation sediments are characterized by a moderate-to-strong degree of chemical weathering, textural immaturity and low recycling sedimentation history. The geochemical composition and detrital zircon U-Pb ages indicate the felsic igneous parent rocks eroded from the central Great Xing'an Range. The sedimentological characteristics indicate a braided river origin under the warm and semi-arid climate. The 26Al/10Be burial dating does not give a conclusive stratigraphic age, but the integrated paleomagnetic and electron spin resonance (ESR) dating strategies constrain the stratigraphic age of the Baitushan Formation to be ∼ 1.1 Ma. The geomorphological and sedimentological evidence suggests the significant Quaternary uplift of the Great Xing'an Range before at least ∼ 1.1 Ma. The zircon U-Pb ages of the Baitushan Formation record the multi-phase volcanism in the central Great Xing'an Range during the Mesozoic. The closure of Mongol-Okhotsk Ocean and the rollback of the paleo-Pacific plate played a decisive role in the asthenospheric mantle upwelling, crustal uplift and extension, and volcanic activity. The geomorphical and detrital zircon age evidence indicates that the Baitushan Formation is the paleo-channel accumulation of the Yalu River, which implies the birth of the Yalu River no later than 1.1 Ma. This study contributes to deepening our present understanding of the Great Xing'an Range uplift and drainage evolution history in NE China. [ABSTRACT FROM AUTHOR]

Deep fertilization strategy has been proven to be an important fertilizer management method for improving fertilizer utilization efficiency and crop yield. However, the relationship between soil chemical and biochemical characteristics and crop productivity under different fertilization depth patterns still needs comprehensive evaluation. Field tests on spring maize were therefore carried out in the Loess Plateau of China for two successive growing seasons from 2019 to 2020. Four distinct fertilization depths of 5 cm, 15 cm, 25 cm, and 35 cm were used to systematically investigate the effects of fertilization depth on soil physicochemical parameters, enzyme activity, and biochemical properties. The findings demonstrated that although adjusting fertilization depths (D15, D25) did not significantly affect the soil organic carbon content, they did significantly improve the soil chemical and biochemical characteristics in the root zone (10–30 cm), with D25 having a greater influence than D15. Compared with D5, the total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), Olsen-P, dissolved organic carbon, and nitrogen (DOC and DON) in the root zone of D25 significantly increased by 12.02%, 7.83%, 22.21%, 9.56%, 22.29%, and 26.26%, respectively. Similarly, the urease, invertase, phosphatase, and catalase in the root zone of D25 significantly increased by 9.56%, 13.20%, 11.52%, and 18.05%, while microbial biomass carbon, nitrogen, and phosphorus (MBC, MBN, and MBP) significantly increased by 18.91%, 32.01% and 26.50%, respectively, compared to D5. By optimizing the depth of fertilization, the distribution ratio of Ca 2 –P and Ca 8 –P in the inorganic phosphorus components of the root zone can also be increased. Therefore, optimizing fertilization depth helps to improve soil chemical and biochemical characteristics and increase crop yield. The results of this study will deepen our understanding of how fertilization depth influence soil properties and crop responses. • Suitable fertilization depth improved the soil biochemical properties. • Changing the fertilization depth regulated the inorganic phosphorus components proportion. • Optimizing fertilization depth (25 cm) contributes to maize yield by matching with the depth of the main root system. [ABSTRACT FROM AUTHOR]

Objective: To analyze the positive and recurrence rates of different autoantibody-associated demyelination disorders in children in Southwest China, and describe the clinical, radiological, and prognostic features of the myelin oligodendrocyte glycoprotein antibody (MOG-ab) and aquaporin-4 antibody (AQP4-ab) associated disease. This study also summarizes steroid maintenance therapy approaches for MOG-ab-positive children. Methods: A total of 160 children presenting with acquired demyelinating syndromes (ADS) between January 2016 and December 2019 were tested for MOG-ab and AQP4-ab. Clinical data, MRI scans, and survival analyses were compared between MOG-ab-positive and AQP4-ab-positive children. Evolution of serologic status and treatment response to immunosuppressants were collected in MOG-ab-positive children. Results: Of the 160 included children, the MOG-ab positivity rate (47.4%) was significantly higher than the AQP4-ab (5%) positivity rate. The recurrence rate for AQP4-ab disease (71.4%) was higher than that of MOG-ab disease (30.1%). For 135 children with both MOG-ab and AQP4-ab tested, the median age at onset was 7 (interquartile range [IQR] 5–10) years, and the median follow-up period was 19 (IQR 13–27.5) months. MOG-ab-positive children more frequently presented with acute disseminated encephalomyelitis, had deep gray matter lesions on MRI, had a better clinical and radiological recovery, and were less likely to have sustained disability than AQP4-ab-positive children. In MOG-ab-positive and AQP4-ab-positive children, maintenance therapy was a protective factor for recurrence, but presenting optic neuritis was a predictor of earlier relapse. A high Expanded Disability Status Scale score at onset was associated with sustained disability. Steroid maintenance therapy longer than 6 months after the initial attack was associated with a lower risk of a second relapse in MOG-ab-positive children. On serial serum MOG antibody analysis, clinical relapse occurred in 34.6% of children with persistent seropositivity, but none of the children who converted to seronegative status experienced relapse. Conclusion: The MOG antibody is more common in children with ADS than the AQP4 antibody. MOG-ab-positive children are characterized by distinct clinical and radiological features. Although some MOG-ab-positive children experience relapsing courses or have persistently seropositive status, they still predict a better outcome than AQP4-ab-positive children. [ABSTRACT FROM AUTHOR]

The Laoyingqing Pb–Zn deposit is located on the southwestern margin of the Yangtze block and on the east side of the Xiaojiang deep fault in the Sichuan–Yunnan–Guizhou Pb–Zn metallogenic triangle area (SYGT). This deposit was first discovered in the silty and carbonaceous slate of the Middle Proterozoic Kunyang Group that is structurally controlled by thrust faults and anticlines. This study is aimed at investigating whether the Laoyingqing deposit has the same ore-forming age and type as other Pb–Zn deposits related to the Pb–Zn metallogenic system and prospecting prediction of the deep and peripheral areas of the deposits in the SYGT. Based on the sphalerite Rb–Sr age dating and S–Sr–Pb isotopic composition analysis of the Laoyingqing Pb–Zn deposit, the following results were obtained. First, the Rb–Sr isochron age of sphalerite is 209.8 ± 5.2 million years (Ma), consistent with the ages of most Pb–Zn deposits in the SYGT (approximately 200Ma), thereby potentially indicating that these Pb–Zn deposits may have been formed synchronously during the late Indosinian orogeny. Second, the Pb isotopic compositions of sulfides show a linear trend on the average crustal Pb evolution curve in 207Pb/204Pb vs. 206Pb/204Pb plot. In addition, Pb isotopic ratios were consistent with the age-corrected Pb isotopic ratios of basement rocks, consequently suggesting that the source of mixed crustal Pb is mainly derived from basement rocks. Combined with the initial 87Sr/86Sr ratios of sphalerite between the (87Sr/86Sr)200Ma value of the basement rocks and that of the Upper Sinian–Permian carbonates, it can be concluded that the ore-forming metals were mainly derived from basement rocks. Third, sulfur isotopic composition of sphalerite from the Laoyingqing deposits shows δ34SCDT values that range mainly from -2.62‰ to 1.42‰, which is evidently lower than the δ34SCDT values of sulfides (8–20‰) from other Pb–Zn deposits in the SYGT. This can be interpreted as a result of mixing with reduced S that was mainly derived from the thermochemically reduced S in the overlying strata and a small amount of reduced S produced by the pyrolysis of S-containing organic matter. We conclude that the Laoyingqing deposit and most of the Pb–Zn deposits in the SYGT are Mississippi Valley-type deposits, thereby providing new ideas for investigating the deep and peripheral areas of Pb–Zn deposits. [ABSTRACT FROM AUTHOR]