A new system for preparing 14C samples was established for a compact accelerator mass spectrometer (GXNU-AMS) at Guangxi Normal University. This sample preparation system consists of three units: a vacuum maintenance unit, a CO2 purification unit, and a CO2 reduction unit, all of which were made of quartz glass. A series of radiocarbon (14C) preparation experiments were conducted to verify the reliability of the system. The recovery rate of graphite obtained was more than 80%. The carbon content in the commercial toner and wood sample was linearly fitted to the CO2 pressure in the measurement unit of the system. The results showed a good linear relationship, indicating that the reliability of the sample preparation system. AMS measurements were conducted on a batch of standard, wood, and dead graphite samples prepared using this system. The results showed that the beam current of 12C- for each sample was more than 40 μA, the carbon contamination introduced during the sample preparation process was ∼ 2 × 10–15, and that the new sample preparation system is compact, low-contamination, and efficient and meets the GXNU-AMS requirements for 14C samples.

In the past 10–15 years, the government of China has made various efforts in tackling excessive antibiotics use. Yet, little is known about their effects at rural primary care settings. This study aimed to determine the impact of government policies and the COVID-19 pandemic on antibiotic prescribing practices at such settings utilizing data from separate studies carried out pre- and during the pandemic, in 2016 and 2021 in Anhui province, China, using identical sampling and survey approaches. Data on antibiotics prescribed, diagnosis, socio-demographic, etc., were obtained through non-participative observation and a structured exit survey. Data analysis comprised mainly descriptive comparisons of 1153 and 762 patients with respiratory infections recruited in 2016 and 2021, respectively. The overall antibiotics prescription rate decreased from 89.6% in 2016 to 69.1% in 2021, and the proportion of prescriptions for two or more classes of antibiotics was estimated as 35.9% in 2016 and 11.0% in 2021. There was a statistically significant decrease in the number of days from symptom onset to clinic visits between the year groups. In conclusion, measures to constrain excessive prescription of antibiotics have led to some improvements at the rural primary care level, and the COVID-19 pandemic has had varying effects on antibiotic use.

Many waterflooding oil fields, injecting water into an oil-bearing reservoir for pressure maintenance, are in their middle to late stages of development. To explore the geological conditions and improve oilfield recovery of the most important well group of the Hu 136 block, located on the border areas of three provinces (Henan, Shandong, and Hebei), Zhongyuan Oilfield, Sinopec, central China, a 14C cross-well tracer monitoring technology was developed and applied in monitoring the development status and recognize the heterogeneity of oil reservoirs. The tracer response in the production well was tracked, and the water drive speed, swept volume of the injection fluid were obtained. Finally, the reservoir heterogeneity characteristics, such as the dilution coefficient, porosity, permeability, and average pore-throat radius, were fitted according to the mathematical model of the heterogeneous multi-layer inter-well theory. The 14C-AMS technique developed in this work is expected to be a potential analytical method for evaluating underground reservoir characteristics and providing crucial scientific guidance for the mid to late oil field recovery process.

Lower-crust-derived adakitic rocks in the Gangdese belt provide important constraints on the timing of Tibetan crustal thickening and on the relative contributions of magmatic and tectonic processes. Here we present geochronological and geochemical data for the Wangdui porphyritic monzogranites in the western Gangdese belt. Zircon U–Pb dating yields emplacement ages of 46–44 Ma. All samples have high Sr (321–599 ppm), low Yb (0.76–1.33 ppm) and Y (10.6–18.3 ppm) contents, with high La/Yb (51.1–72.3) and Sr/Y (21.0–51.4) ratios, indicating adakitic affinities. The low MgO (0.97–1.76 wt %), Cr (7.49–53.6 ppm) and Ni (4.75–29.1 ppm) contents, as well as high 87Sr/86Sr(i) (0.7143–0.7145), low ϵNd(t) (−10.4 to −9.8) and zircon ϵHf(t) (−17.7 to 0.4) values, suggest that the Wangdui pluton most likely originated from partial melting of the thickened ancient lower crust. In combination with previously published data, despite the east–west-trending heterogeneity of crustal composition in the Gangdese belt, the La/Yb ratios of magmatic rocks reveal that both western and eastern segments experienced remarkable crustal thickening in the Eocene. However, in contrast to the thickened juvenile lower crust in the eastern segment formed by the underplating of mantle-derived magmas, tectonic shortening plays a more crucial role in thickening of the ancient basement in western Gangdese. In fact, such Eocene-thickened ancient lower-crust-derived adakitic rocks are widely distributed in the central Himalayan–Tibetan orogen. This, together with the extensive development of fold–thrust belts, suggests that tectonic shortening might be the main mechanism accounting for the crustal thickening associated with the India–Asia collision.

The dynamics of wind-generated water waves in the principal stage of the Phillips theory (Phillips, J. Fluid Mech., vol. 2, 1957, pp. 417–445) is investigated by a combined numerical and analytical approach. We perform a number of high-resolution direct numerical simulation (DNS) of turbulent wind over initially calm water to capture the multistage generation of water waves. Detailed analyses are conducted to evaluate the Phillips theory in both physical space and wavenumber space. Numerical evidence is obtained for the existence of a principal stage when the surface elevation variance grows linearly with time. We further propose a random sweeping turbulence pressure–wave interaction model by introducing the random sweeping hypothesis of air pressure fluctuations to the Phillips theory, and obtain an asymptotic solution of the mean square of surface wave elevations over time. This asymptotic analysis captures the temporal oscillations of surface elevation variance in the principal stage, which is also confirmed by our DNS results. The wavenumber spectrum of surface wave elevations is analysed using a time-dependent norm to elucidate the role of the resonance mechanism on wave generation. In physical space, we use the random sweeping turbulence pressure–wave interaction model to obtain a quantitative prediction of the growth rate of surface elevation variance in the principal stage, which is found to agree with the DNS results better than the original Phillips model.

GPR120 is implicated in the regulation of glucose and lipid metabolism, and insulin resistance. In the current study, we aimed to investigate the role of GPR120 in polycystic ovary syndrome (PCOS). With the adoption of dehydroepiandrosterone, a rat model was established to simulate PCOS in vitro. mRNA and protein expression levels of GPR120 were measured using RT-qPCR and western blot, respectively. In addition, expression levels of testosterone, estradiol, luteinizing hormone and follicle-stimulating hormone, serum total cholesterol and triglyceride were assessed using the corresponding kits. Moreover, haematoxylin and eosin staining was used to detect pathological changes in ovary or liver and oil red staining was utilized to evaluate lipid accumulation. In the present study, GPR120 was downregulated in plasma, liver and ovary in the PCOS rat model. In addition, the GPR120 agonist regulated lipid metabolism in the liver and weight in the PCOS rat model. Furthermore, the GPR120 agonist decreased insulin resistance in the PCOS rat model but improved the ovarian function. It is suggested that GPR120 plays a vital role in suppressing insulin resistance, regulating ovary function and decreasing lipid accumulation in the liver, demonstrating that targeting GPR120 could be an effective method for the improvement of PCOS.

We report on experimental observation of non-laminar proton acceleration modulated by a strong magnetic field in laser irradiating micrometer aluminum targets. The results illustrate the coexistence of ring-like and filamentation structures. We implement the knife edge method into the radiochromic film detector to map the accelerated beams, measuring a source size of 30–110 μm for protons of more than 5 MeV. The diagnosis reveals that the ring-like profile originates from low-energy protons far off the axis whereas the filamentation is from the near-axis high-energy protons, exhibiting non-laminar features. Particle-in-cell simulations reproduced the experimental results, showing that the short-term magnetic turbulence via Weibel instability and the long-term quasi-static annular magnetic field by the streaming electric current account for the measured beam profile. Our work provides direct mapping of laser-driven proton sources in the space-energy domain and reveals the non-laminar beam evolution at featured time scales.

Several candidates of universal influenza vaccine (UIV) have entered phase III clinical trials, which are expected to improve the willingness and coverage of the population substantially. The impact of UIV on the seasonal influenza epidemic in low influenza vaccination coverage regions like China remains unclear. We proposed a new compartmental model involving the transmission of different influenza subtypes to evaluate the effects of UIV. We calibrated the model by weekly surveillance data of influenza in Xi'an City, Shaanxi Province, China, during 2010/11–2018/19 influenza seasons. We calculated the percentage of averted infections under 2-month (September to October) and 6-month (September to the next February) vaccination patterns with varied UIV effectiveness and coverage in each influenza season, compared with no UIV scenario. A total of 195 766 influenza-like illness (ILI) cases were reported during the nine influenza seasons (2010/11–2018/19), of which the highest ILI cases were among age group 0–4 (59.60%) years old, followed by 5–14 (25.22%), 25–59 (8.19%), 15–24 (3.75%) and ⩾60 (3.37%) years old. The influenza-positive rate for all age groups among ILI cases was 17.51%, which is highest among 5–14 (23.75%) age group and followed by 25–59 (16.44%), 15–24 (16.42%), 0–4 (14.66%) and ⩾60 (13.98%) age groups, respectively. Our model showed that UIV might greatly avert influenza infections irrespective of subtypes in each influenza season. For example, in the 2018/19 influenza season, 2-month vaccination pattern with low UIV effectiveness (50%) and coverage (10%), and high UIV effectiveness (75%) and coverage (30%) could avert 41.6% (95% CI 27.8–55.4%) and 83.4% (80.9–85.9%) of influenza infections, respectively; 6-month vaccination pattern with low and high UIV effectiveness and coverage could avert 32.0% (15.9–48.2%) and 74.2% (69.7–78.7%) of influenza infections, respectively. It would need 11.4% (7.9–15.0%) of coverage to reduce half of the influenza infections for 2-month vaccination pattern with low UIV effectiveness and 8.5% (5.0–11.2%) of coverage with high UIV effectiveness, while it would need 15.5% (8.9–20.7%) of coverage for 6-month vaccination pattern with low UIV effectiveness and 11.2% (6.5–15.0%) of coverage with high UIV effectiveness. We conclude that UIV could significantly reduce the influenza infections even for low UIV effectiveness and coverage. The 2-month vaccination pattern could avert more influenza infections than the 6-month vaccination pattern irrespective of influenza subtype and UIV effectiveness and coverage.

As the corona virus disease 2019 (COVID-19) pandemic continues around the world, understanding the transmission characteristics of COVID-19 is vital for prevention and control. We conducted the first study aiming to estimate and compare the relative risk of secondary attack rates (SARs) of COVID-19 in different contact environments. Until 26 July 2021, epidemiological studies and cluster epidemic reports of COVID-19 were retrieved from SCI, Embase, PubMed, CNKI, Wanfang and CBM in English and Chinese, respectively. Relative risks (RRs) were estimated in pairwise comparisons of SARs between different contact environments using the frequentist NMA framework, and the ranking of risks in these environments was calculated using the surface under the cumulative ranking curve (SUCRA). Subgroup analysis was performed by regions. Thirty-two studies with 68 260 participants were identified. Compared with meal or gathering, transportation (RR 10.55, 95% confidence interval (CI) 1.43–77.85), medical care (RR 11.68, 95% CI 1.58–86.61) and work or study places (RR 10.15, 95% CI 1.40–73.38) had lower risk ratios for SARs. Overall, the SUCRA rankings from the highest to the lowest were household (95.3%), meal or gathering (81.4%), public places (58.9%), daily conversation (50.1%), transportation (30.8%), medical care (18.2%) and work or study places (15.3%). Household SARs were significantly higher than other environments in the subgroup of mainland China and sensitive analysis without small sample studies (<100). In light of the risks, stratified personal protection and public health measures need to be in place accordingly, so as close contacts categorising and management.

Chronic inflammation exerts pleiotropic effects in the aetiology and progression of chronic obstructive pulmonary disease (COPD). Glucosamine is widely used in many countries and may have anti-inflammatory properties. We aimed to prospectively evaluate the association of regular glucosamine use with incident COPD risk and explore whether such association could be modified by smoking in the UK Biobank cohort, which recruited more than half a million participants aged 40–69 years from across the UK between 2006 and 2010. Cox proportional hazards models with adjustment for potential confounding factors were used to calculate hazard ratios (HR) as well as 95 % CI for the risk of incident COPD. During a median follow-up of 8·96 years (interquartile range 8·29–9·53 years), 9016 new-onset events of COPD were documented. We found that the regular use of glucosamine was associated with a significantly lower risk of incident COPD with multivariable adjusted HR of 0·80 (95 % CI, 0·75, 0·85; P < 0·001). When subgroup analyses were performed by smoking status, the adjusted HR for the association of regular glucosamine use with incident COPD were 0·84 (0·73, 0·96), 0·84 (0·77, 0·92) and 0·71 (0·62, 0·80) among never smokers, former smokers and current smokers, respectively. No significant interaction was observed between glucosamine use and smoking status (Pfor interaction = 0·078). Incident COPD could be reduced by 14 % to 84 % through a combination of regular glucosamine use and smoking cessation.

Dilated cardiomyopathy is characterised by dilatation and impaired contraction of the left ventricle or both ventricles, which is the most common childhood cardiomyopathy. In recent years, it has been recognised that many sorts of genetic mutations may contribute to dilated cardiomyopathy. We now report a rare association of dilated cardiomyopathy with site mutation of BMPR2 gene. We did not find such an association reported in the medical literature.

Flixweed [Descurainia sophia (L.) Webb ex Prantl] is a notorious broadleaf weed that is widely distributed in winter wheat–growing areas of China and has evolved resistance to tribenuron-methyl mainly due to target-site resistance (TSR) mutations in acetolactate synthase (ALS). In the current research, two ALS genes were identified in tribenuron-methyl–susceptible (TS) or tribenuron-methyl–resistant (TR) D. sophia. Resistance mutations of Asp-376-Glu and Pro-197-Ala were identified on ALS1 and ALS2 isozymes in TR D. sophia, respectively. The TR D. sophia evolved 10,836.3-fold resistance to tribenuron-methyl and displayed cross-resistance to multiple ALS-inhibiting herbicides with different chemical structures. Dose response experiments and ALS activity assay indicated that two mutated ALS isozymes contributed differentially in resistance to tribenuron-methyl, flucetosulfuron, and pyribenzoxim. In addition, the relative expression level of the ALS1 gene was 2.2- and 1.6-fold higher than ALS2 genes in TR D. sophia at 1 and 7 d after tribenuron-methyl treatment, respectively. In contrast, the relative expression level of ALS1 and ALS2 in TS D. sophia is similar. This is the first research that explored different roles of ALS isozymes in resistance to ALS-inhibiting herbicides, which might provide a new perspective for the weed resistance management.

Somatic cell nuclear transfer (SCNT) holds vast potential in agriculture. However, its applications are still limited by its low efficiency. Histone 3 lysine 9 trimethylation (H3K9me3) was identified as an epigenetic barrier for this. Histone demethylase KDM4D could regulate the level of H3K9me3. However, its effects on buffalo SCNT embryos are still unclear. Thus, we performed this study to explore the effects and underlying mechanism of KDM4D on buffalo SCNT embryos. The results revealed that compared with the IVF embryos, the expression level of KDM4D in SCNT embryos was significantly lower at 8- and 16-cell stage, while the level of H3K9me3 in SCNT embryos was significantly higher at 2-cell, 8-cell, and blastocyst stage. Microinjection of KDM4D mRNA could promote the developmental ability of buffalo SCNT embryos. Furthermore, the expression level of ZGA-related genes such as ZSCAN5B, SNAI1, eIF-3a, and TRC at the 8-cell stage was significantly increased. Meanwhile, the pluripotency-related genes like POU5F1, SOX2, and NANOG were also significantly promoted at the blastocyst stage. The results were reversed after KDM4D was inhibited. Altogether, these results revealed that KDM4D could correct the H3K9me3 level, increase the expression level of ZGA and pluripotency-related genes, and finally, promote the developmental competence of buffalo SCNT embryos.

A study was conducted to identify whether composted manure and straw amendments (replacement of a portion of chemical fertilizer [50% of the total nitrogen application] with composted pig manure, and straw return [all straw from the previous rice crop] combined with chemical fertilizer) compared with no fertilization and chemical fertilizer only would change the dominant species of wheat-associated weeds as well as influence their growth and seed yield in a rice (Oryza sativa L.)–wheat (Triticum aestivum L.) rotation system. The study was initiated in 2010, and the treatment effects on the species, density, plant height, shoot biomass, seed yield of dominant weeds, and wheat yields were assessed in 2017 and 2018. Fertilization significantly increased the height, density, and yield of wheat, as well as the shoot biomass of wheat-associated weeds, but decreased the weed species number. A total of 17 and 14 weed species were recorded in the experimental wheat fields in 2017 and 2018, respectively. The most dominant weed species were American sloughgrass [Beckmannia syzigachne (Steud.) Fernald] and catchweed bedstraw (Galium aparine L.), which made up more than 64% of the weed community in all treatments. When the chemical fertilizer application was amended with pig manure compost and straw return, the relative abundance of B. syzigachne significantly decreased, while the relative abundance of G. aparine significantly increased. The application of the chemical fertilizer-only treatment resulted in increases in the density, shoot biomass, and seed yield of B. syzigachne, while the composted manure and straw amendments applied together with chemical fertilizer led to significant increases in the density, shoot biomass, and seed yield of G. aparine. Consequently, further research on ways to promote greater cropping system diversity will be needed to prevent the selection of weed species that are adapted to a limited suite of crop management practices.