Tree-ring cellulose is a commonly used material for radiocarbon analysis. Extracting cellulose is labor-consuming and several devices that enable batchwise extraction have been developed. However, these devices bear the risk of sample contamination. The present study describes a new device which improves upon two aspects of currently available devices. First, to prevent cross-sample-contamination, we redesigned the drainage module to enable independent removal of chemical waste from each individual sample funnel. Second, we added covers to the sample funnels to reduce the risk of external contamination. Cellulose purity (i.e., holocellulose) was confirmed by Fourier Transform Infrared (FTIR) Spectroscopy. Furthermore, accuracy of the radiocarbon analysis was confirmed by results of 14C-blank samples and samples of known age. In conclusion, while maintaining labor-saving, our modified device significantly reduces the risk of sample contamination during extraction of tree-ring cellulose.

In 2018, an Ionplus 200 kV MIni-CArbon DAting System (MICADAS) accelerator mass spectrometer (AMS) was installed at the Laboratory of AMS Dating and the Environment, Nanjing University (NJU-AMS Laboratory), China. The NJU-AMS Laboratory is largely devoted to research on radiocarbon dating and 14C analysis in fields of earth, environmental and archaeological sciences. The laboratory has successfully employed various pretreatment methods, including routine pretreatment of tree rings, buried wood and subfossil wood, seeds, charcoal, pollen concentrates, organic matter, and shells. In this study, operational status of the NJU-AMS is presented, and results of radiocarbon measurements made on different sample types are reported. Measurements on international standards, references of known age, and blank samples demonstrate that the NJU-AMS runs stably and has good reproducibility on measurement of single samples. The facility is capable of measuring 14C in samples with the precision and accuracy that meet the requirements for investigating annual 14C changes, history-prehistory age dating, and Late Quaternary stratigraphic chronology research.

The Holocene is a critical period for understanding the East Asian monsoon system (EAM) over long timescales, but high-precision dating and high-resolution records from the Holocene epoch at monsoonal margins of East Asia are lacking. Here, on the basis of closely spaced radiocarbon and optically stimulated luminescence dating results obtained from a typical loess–paleosol sequence on the northern Chinese Loess Plateau (CLP), we provide an independent age-based, high-resolution depositional record of East Asian summer (EASM) and winter monsoons (EAWM) variations over the past ~14 ka. We find that both the EASM and EAWM simultaneously strengthened sometime during the Holocene optimum (~7–5 ka BP), with greater seasonality, and weakened during the Late Holocene. These findings are counterintuitive to our understanding of the EAM variations based on loess records at suborbital scales during interglacial periods, providing an alternative scenario of the monsoon system evolution. We postulate that high-latitude forcing and surface feedbacks, such as vegetation change, have modulated the EAM variations during the Holocene warmth.

To accurately calculate the turbulent exchange coefficient, the contribution of multi-scale turbulent transportation needs to be considered, especially in the complex terrain of the coastal area. In September 2019, a comprehensive observation experiment on the offshore atmospheric boundary layer was carried out at the Yangmeikeng Ecological Monitoring Station and Sai Chung Gulf. Through scale decomposition, it is shown that the turbulent motion in the atmospheric boundary layer in the coastal area is affected by the underlying surface, such as that of the coastal land or the sea–land boundary. This is the main reason behind the phenomenon whereby different scales make different contributions to momentum flux. Different multi-scale characteristics of turbulent structures on the underlying surface affect the drag coefficient. Through wavelet transform and finite element method, the characteristics of the multi-scale flow structures produced by the complicated offshore terrain are analysed. It is found that large-scale flow structures enhance the pulsating intensity at the small scale, but the large-scale coherence characteristics are different from those at the small scale. In summary, in comparing these three sites, the flux exchange on the roof is greatest, followed by that on the tower. In the Gulf, the flux exchange is mainly dependent on small-scale structures, which are linked with the smallest values.

Maternal syphilis not only seriously affects the quality of life of pregnant women themselves but also may cause various adverse pregnancy outcomes (APOs). This study aimed to analyse the association between the related factors and APOs in maternal syphilis. 7,030 pregnant women infected with syphilis in Henan Province between January 2016 and December 2022 were selected as participants. Information on their demographic and clinical characteristics, treatment status, and pregnancy outcomes was collected. Multivariate logistic regression models and chi-squared automatic interaction detector (CHAID) decision tree models were used to analyse the factors associated with APOs. The multivariate logistic regression results showed that the syphilis infection history (OR = 1.207, 95% CI, 1.035–1.409), the occurrence of abnormality during pregnancy (OR = 5.001, 95% CI, 4.203–5.951), not receiving standard treatment (OR = 1.370, 95% CI, 1.095–1.716), not receiving any treatment (OR = 1.313, 95% CI, 1.105–1.559), and a titre ≥1:8 at diagnosis (OR = 1.350, 95%CI, 1.079–1.690) and before delivery (OR = 1.985, 95%CI, 1.463–2.694) were risk factors. A total of six influencing factors of APOs in syphilis-infected women were screened using the CHAID decision tree model. Integrated prevention measures such as early screening, scientific eugenics assessment, and standard syphilis treatment are of great significance in reducing the incidence of APOs for pregnant women infected with syphilis.

The land cover of the Sanjiang Plain has changed dramatically since the 1950s. Although previous studies have analysed its spatiotemporal dynamics at long time intervals, a near real-time and accurate representation of the interannual evolution of cropping patterns in this region is of far-reaching importance for rationally allocating agricultural resources and ensuring food security. Based on the 30 m and 10 m land cover datasets in 2015 and 2017–2019, the current study used Landsat-8 satellite data in 2014, 2016 and 2020 to identify paddy rice and dryland crops using a decision tree classification approach and constructed the annual cropland datasets of the Sanjiang Plain from 2014 to 2020. The results show that the overall classification accuracies of crop datasets exceeded 95%, and the Kappa coefficients were higher than 0.92. The average annual accuracies of users and producers were 93% and 94% for rice fields and 97% and 95% for dryland crops, respectively. During the 7 years, the total area of paddy fields and dryland crops decreased by 5% and 8%. However, with minor positive and negative variation between years. 24.2% of paddy rice and 42% of dryland crops has been cultivated under 4 years. The centres of gravity for both crops mainly aggregated in the central counties with the migration direction and magnitude varying interannually. The current study emphasizes the importance of establishing annual high-resolution crop datasets to track the detailed spatio-temporal trajectories of cropping patterns that are essential to support sustainable cropland management and agricultural development.

Earth-contact mechanism (ECM), a type of mechanism to keep the system in contact with the earth and to move with the terrain changes. This paper uses the virtual equivalent parallel mechanism (VEPM) to convert the terrain data into the kinematical variables of the moving platform in the VEPM, and further analyzes the performance of the VEPM at each terrain point. Then, the comprehensive performance of the VEPM is chosen as the optimization goal, and a task-oriented dimensional optimization approach combined with the particle swarm algorithm and the neural network algorithm is proposed. This paper conducted a comparative experiment to verify the superiority of the new approach in optimizing the ECM’s comprehensive performance, whose performance analysis also can be applied into the layout design of the ECM. This paper proposed an analysis method to construct the ECM’s performance map based on the digital terrain map, which helps the control system and operator to make the optimal control decision.

In October 2015, the Chinese Government announced that the one-child policy had finally been replaced by a universal two-child policy. China’s universal two-child policy is highly significant because, for the first time in 36 years, no one in an urban city is restricted to having just one child. This cross-sectional study was conducted to explore future fertility intentions and factors influencing individual reproductive behaviour (whether to have two children) in Dalian City. A total of 1370 respondents were interviewed. The respondents’ mean ideal number of children was only 1.73, and urban respondents’ sex preference was symmetrical. A total of 19.0% of the respondents were unmarried, 64.5% were married and had childbearing experience and only 6.3% of married respondents had two children. Among the 1370 participants, 30.4% stated that they would have a second child, while 69.6% refused to have a second child in the future. Binary logistic regression analysis (Model 1) showed that the following characteristics were associated with having only one child in the future: being female, being older, having a lower education level, being born in Dalian, having a lower family income and reporting one child as the ideal number of children. Model 2 (comprising only respondents with childbearing experience) showed that respondents who were female, had a lower family income and were unable to obtain additional financial support from parents were more likely to intend to stick at one child. In addition, respondents’ ideal number of children and childbearing experiences had a significant influence on future fertility intentions. These results suggest that fertility intentions and reproductive behaviours are still below those needed for replacement level fertility in Dalian City. China’s policymakers should pay more attention to these factors (socioeconomic characteristics, economic factors, desired number of children and childbearing experiences) and try to increase individual reproductive behaviour.

The construction of halloysite spherical capsules (halloysite aerogels) was reported for the first time in our previous work. The excellent performance of the microcapsule in functional carrying was also found in our further research. In this work, the anti-icing surface was fabricated by using halloysite nanotubes and halloysite spherical microcapsules. The fabrication of the anti-icing coating was investigated, and the ice nucleation behavior of droplet on the coating surface was studied. The modified halloysite nanotubes (F-HNTs) and the modified halloysite microcapsules (F-HAs) were characterized by Fourier-transform infrared spectroscopy, thermal gravimetric, and pore size distribution. The results show that the introduction of F-HNTs and F-HAs have successfully formed a micro-nano structure on the coating surface with superhydrophobicity performance. The icing temperature of the coating has decreased 2.3 °C compared with bare glass, and the ice adhesion strength has decreased 82%. According to the ice dynamic mechanics, the ice nucleation rate on the coating is significantly reduced, thus the halloysite microcapsule coating has good icephobic performance.

Starch content is an important trait in barley. To evaluate the genetic diversity and identify molecular markers of starch content in barley, 40 cultivated barley genotypes collected from different regions, including genotypes whose starch content is at either the high or low end of the spectrum (15), were used in this study. All the genotypes were re-sequenced by the double-digest-restriction associated DNA sequencing method, and a total of 299,103 single-nucleotide polymorphism (SNP) markers were obtained. The genotypes were divided into four sub-populations based on FASTSTRUCTURE, principal component analysis and neighbour-joining tree analysis. All four sub-populations had a high linkage disequilibrium, especially group 3, whose members were recently bred for malting in the Jiangsu coastal area. The starch content of the barley lines was evaluated during three growing seasons (2014–2017), and the average values of starch content across the three growing seasons at the low and high ends were 51.5 and 55.0%, respectively. The starch content was affected by population structure, the barley in group 2 had a low starch content, while the barley in group 4 had a high starch content. Twenty-six SNP markers were identified as being significantly associated with starch content (P ⩽ 0.001) based on the average values across the three growing seasons using the mixed linear model method. These SNP markers were located on chromosomes 1H and 4H, and were considered loci of qSC1-1 and qSC4-1, respectively. The major identified QTLs for starch content are helpful for further research on carbohydrates and for barley breeding.

The Daheyan region, situated in the SW of the Bogda Mountains in eastern Tianshan, is important for understanding the accretionary history of the Central Asian Orogenic Belt. We investigated Carboniferous intrusions from the Daheyan area, SW Bogda Mountains, obtaining new zircon U–Pb ages, whole-rock geochemical data and Hf isotope data for these intrusions. Zircon U–Pb dating indicates that syenogranite, diorite, granodiorite and monzonite of the Daheyan intrusions were all formed during late Carboniferous (311–303 Ma) magmatism. The syenogranite has geochemical characteristics of A-type granites that were mainly sourced from melting of juvenile crust. In comparison, the low-Mg-number diorite intrusion, with tholeiite and metaluminous features, was derived from young crust and mixed some mantle materials. The granodiorite and monzonite are both I-type granites, and are both sourced from the melting of juvenile crust. Based on a comprehensive analysis of previous geochronological, geochemical and isotopic data of magmatic and sedimentary rocks in the Bogda–Harlik belt, we consider that late Carboniferous intrusive rocks of the Bogda Mountains formed in an intra-arc extension related to a continent-based arc setting.

We investigated climate niches of grasses at regional scales and quantitatively reconstruct Asian monsoon precipitation at the sand-loess transitional zone in northern China. Our results provide direct evidence that certain grass lineages have been specialized in specific habitats: Pooideae grasses stand out and occupy a much cooler environment than all other subfamilies; Pooideae, Aristidoideae, and Chloridoieae occupy dry environments. Pooideae grasses occupy the coldest and driest environments compared to all other subfamilies, with a mean annual temperature (MAT) and precipitation (MAP) of ~13.6 to ~15.3°C and 224 to ~1674 mm, respectively, at a regional scale. We built a database for grasses and their corresponding climate parameters. Based on this database, past climate parameters at the margin of the Asian summer monsoon since ~70 ka were quantitatively reconstructed by phytolith assemblages. They show that this area was dominated by cold- and dry-adapted grasses since ~70 ka with a MAT and MAP of ~3.3 to ~11.0 °C and ~442 to ~900 mm, respectively, generally consistent with the results of phytolith-based transfer function reconstructions and with the results of previous nearby pollen-based quantitative reconstructions. With the improvement of the species-climate and ecosystem dataset, our database-based method is a promising quantitative reconstruction approach to past climatic change in the monsoon region.

Dairy cows with type II ketosis display hepatic fat accumulation and hyperinsulinemia, but the underlying mechanism is not completely clear. This study aimed to clarify the regulation of lipid metabolism by insulin in cow hepatocytes. In vitro, cow hepatocytes were treated with 0, 1, 10, or 100 nm insulin in the presence or absence of AICAR (an AMP-activated protein kinase alpha (AMPKα) activator). The results showed that insulin decreased AMPKα phosphorylation. This inactivation of AMPKα increased the gene and protein expression levels of carbohydrate responsive element-binding protein (ChREBP) and sterol regulatory element-binding protein-1c (SREBP-1c), which downregulated the expression of lipogenic genes, thereby decreasing lipid biosynthesis. Furthermore, AMPKα inactivation decreased the gene and protein expression levels of peroxisome proliferator-activated receptor-α (PPARα), which upregulated the expression of lipid oxidation genes, thereby increasing lipid oxidation. In addition, insulin decreased the very low density lipoprotein (VLDL) assembly. Consequently, triglyceride content was significantly increased in insulin treated hepatocytes. Activation of AMPKα induced by AICAR could reverse the effect of insulin on PPARα, SREBP-1c, and ChREBP, thereby decreasing triglyceride content. These results indicate that insulin inhibits the AMPKα signaling pathway to increase lipid synthesis and decrease lipid oxidation and VLDL assembly in cow hepatocytes, thereby inducing TG accumulation. This mechanism could partly explain the causal relationship between hepatic fat accumulation and hyperinsulinemia in dairy cows with type II ketosis.