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Increases in population size are associated with the adoption of Neolithic agricultural practices in many areas of the world, but rapid population growth within the Dingsishan cultural group of southern China pre-dated the arrival of rice and millet farming in this area. In this article, the authors identify starch grains from taros (Colocasia) and yams (Dioscorea) in dental calculus and on food-processing tools from the Dingsishan sites of Huiyaotian and Liyupo (c. 9030-6741 BP). They conclude that the harvesting and processing of these dietary staples supported an Early Holocene population increase in southern East Asia, before the spread of rice and millet farming. Keywords: Southern China, Early Holocene, Dingsishan, microfossil analysis, dental calculus, starch grains, taro, Introduction Around 10 000 BP, the first open settlements emerged on terraces along the Yongjiang River in southern Guangxi in southern China (Fu 2002; Zhang & Hung 2010, 2012; Hung […]

[Objective] To reveal the spatial and temporal evolution characteristics of soil water erosion in the middle reaches of the Yellow River in the rich and coarse sediment area from 2000 to 2020, and analyze its dynamic driving force. [Methods] Based on the RUSLE model, the annual soil water erosion modulus in the rich and coarse sediment area was calculated, and the variation characteristics of soil water erosion intensity in 2000, 2005, 2010, 2015, and 2020 were analyzed. The spatial-temporal characteristics of soil water erosion modulus were explored by using the Sen+MK trend analysis method combined with the Hurst index, and the factor probing in the parameter-optimal geographical detector with the interactive probing were used to quantify the explanatory power of six factors, namely average annual precipitation, elevation, slope, vegetation cover, land use/cover type, and soil type, on the spatial distribution of soil water erosion. [Results] (1) The area of moderate, intense, extremely intense and severe erosion in the rich and coarse sediment area decreased by 48.09%, 77.93%, 83.01%, and 36.13%, respectively, and the area of slight and mild erosion increased by 46.22% and 0.33%, respectively, in the five periods from 2000 to 2020. At the present stage, the sandy and coarse sandy area was dominated by slight and mild erosion, and the proportion of the two was 62.49% and 42.07% respectively. (2) The overall inter-annual change of soil water erosion modulus in the rich and coarse sediment area showed a fluctuating and significant downward trend, from 2 214.89 t/(km2·a) in 2000 to 1 169.44 t/(km2·a) in 2020. The spatial variation trend of soil water erosion modulus in the rich and coarse sediment area from 2000 to 2020 was mainly in a decreasing state, accounting for 76.13% of the total area, and would continue to be in a decreasing state in the future, with an area share of 62.50%. (3) The explanatory power of the interactions among the six factors was greater than that of single factor, and it was mainly manifested as nonlinear enhancement and double-factor enhancement; soil water erosion in the rich and coarse sediment area was dominated by precipitation and land use/cover in 2000—2005, and by vegetation cover and land use/cover in 2010—2020. [Conclusion] Soil water erosion condition in the rich and coarse sediment area will be improved continuously from 2000 to 2020; in the future, the soil water erosion modulus of 62.50% of the regions will continue to decline or decline in the future, but there is still a potential risk of increase in 20.44% of the area; the land use/cover pattern has changed by the project of returning farmland to forests and grassland, which made the soil water erosion in the rich and coarse sediment area. The driving force of soil water erosion in the rich and coarse sediment area changes dynamically; the slope factor needs to be fully considered when optimizing the land use/cover pattern for the prevention and control of soil water erosion in the rich and coarse sediment area in the future.

[Objective] The study is aimed at revealing the response of runoff to land use change in the Kuye River Basin and predicting future runoff change. [Methods] Taking the Kuye River Basin as the study area, based on the SWAT and PLUS models, the changes of runoff under different land use scenarios were quantitatively analyzed by using the land use data of 2000, 2005, 2010, 2015, 2020 and the data of 2025 and 2030 that were predicted from the natural development scenario. [Results] (1) The R2 and NS of the SWAT model during the periodic and validation periods were greater than 0.7. The overall accuracy of PLUS model was 0.877 4, and the Kappa coefficient was 0.802 1. The two models had good applicability in the Kuye River Basin. (2) From 2000 to 2020, forest land and construction land increased by 102.92 and 600.90 km2, respectively, while cultivated land, grassland, water area, and unused land decreased by 277.15, 366.25, 40.44 and 19.98 km2, respectively. (3) The average annual runoff depth in the Kuye River Basin presented a spatial distribution pattern of “lower in the upper reaches, higher in the lower reaches, lower in the west, and higher in the east”. (4) Changing land use data while ensuring that other input data remains unchanged, the results of scenario analysis showed that the decrease of forest land and grassland area would promote runoff, and the increase of construction land area would also promote runoff. (5) Under the natural development scenario, there was no significant change in the spatial distribution pattern of land use in the Kuye River Basin in 2025 and 2030, and the land use was still dominated by cultivated land and grassland, with the average annual runoff increasing by 3.21% and 5.00%, respectively, compared with 2020. [Conclusion] There was a close relationship between land use and runoff change. From the perspective of scenario analysis, forest land and grassland inhibited runoff, while construction land promoted runoff. Under the future natural development scenario, runoff increased with land use change. The research could provide scientific basis for the optimization of land use structure and rational planning of water and soil resources in the Kuye River Basin.

Over the past few decades, polymers with dynamic covalent bonds have received a lot of attention due to their self‐healing, shape memory, and environmental adaptation properties. However, most of them require a change in catalyst or environmental conditions to achieve bond reduction and exchange reactions, and the harsh conditions are not conducive to the practical application of the material. However, the dr‐polyurea based polyurethane (PUU) can be prepared at low temperatures, and can be worn and rebuilt in a catalyst free and mild environment, thus showing excellent self‐healing function. In this paper, the unique dynamic reaction mechanism of hindered urea bond (HUB), the properties of related polymers and the development of frontier are reviewed. In addition, the performance research of HUB and the application prospect of innovative synthetic PUU are also reviewed. [ABSTRACT FROM AUTHOR]

The brake system is a key component of a high-speed train, which suffers intense wheel-rail interactions caused by wheel polygonal wear (WPW) in realistic working conditions. To explore the dynamic characteristics of the disc brake systems with WPW, a rigid-flexible coupled vehicle dynamics model is proposed. The developed model systematically takes into account the flexible deformation of brake components and wheelsets, measured WPW and non-linear factors such as wheel-rail interaction, disc-pad friction and non-linear damping characteristics. It allows the dynamic behaviors of the vehicle brake system in service to be accurately and effectively revealed. The model is verified using line test data, and then the dynamic characteristics of disc brake systems with WPW are investigated in details. The results show that for vehicle speed below 80 km/h and depths of WPW below 0.04 mm, the effect of WPW on the vibration of the caliper is slight. However, as vehicle speed and wear depth continue to rise, the vibration of the caliper increases noticeably. Furthermore, the effects of vehicle speed and wear depth on brake disc vibration are more obvious, and increasing vehicle speed and wear depth will steadily deteriorate the vibration of the disc. Besides, the effect of WPW is particularly pronounced on the dynamic behavior of the brake units closer to the wheels. Overall, the influence of wheel polygon cannot be neglected in the study of dynamic characteristics of brake system. At the same time, the proposed model can also be applied in the strength evaluation of brake components and the study of the tribological behaviors within the brake interface. [ABSTRACT FROM AUTHOR]

Mine gas accidents have received widespread attention at home and abroad, because mine gas accidents often cause casualties and property losses once they occur. This study was conducted in order to have a more comprehensive understanding of the research status of and research hotspots in coal mine gas management at home and abroad, and to provide references for relevant researchers' studies and literature searches. Using the Web of Science (WOS) core database as the data source, this paper analyzed the data from the period of 2000–2023 under the headings of "gas governance", "Gas Control Technology", "Pre-mining gas methods in coal mines", "Methods of Gas Mining in Coal Mines", "Post-mining gas", and "Post-mining gas methods in coal mines". "Methods in Coal Mines", "Methods of Gas Mining in Coal Mines", and "Post-mining Gas Methods in Coal Mines" were searched, and the CiteSpace tool was utilized to provide a multi-dimensional visual presentation of the literature, including authors, the number of journals issued, countries of issue, keywords, etc., in order to explore the research hotspots in this field. The analysis results show the following: the development process in the field of gas prevention and control is mainly divided into the three stages of initial exploration, steady development, and explosive surge; China, Australia, and the United States are the top three countries in terms of the number of articles published, and they have a greater influence in the field, but there is a closer connection between the regions in Europe; a certain group size has been formed by the researchers and research institutes in this field, the China University of Mining and Technology is more active in this field, ranking as the first in terms of the number of articles issued, and it has a cooperative relationship with many universities; Kai Wang and Enyuan Wang are the core authors in this field, while C. Ozgen Karacan also has a large body of research in the field, and his research results are widely recognized; the main journals issued in this field are Fuel and Energy Policy, while other journals have been frequently cited, and these journals have an important role in the field. In these journals, "Coal mine methane: A review of capture and utilization practices with benefits to mining safety and to greenhouse gas reduction" is one of the most important articles in the field. Thin coal seams, coal mining workings, and coal and gas protrusion are current research hotspots. [ABSTRACT FROM AUTHOR]

Fascioliasis is an important zoonotic helminthic disease caused by Fasciola hepatica and poses a serious threat to global public health. To evade the immune response of its host (humans or animals), F. hepatica secretes various antioxidant enzymes such as glutathione transferase (GST) to facilitate its invasion, migration and parasitism in vivo. To investigate the biological functions of a novel omega-class GST (GSTO), the molecular features of GSTO2 of F. hepatica were analyzed by online software, and the biochemical properties in vitro of recombinant GSTO2 (rGSTO2) were dissected. Then, the regulatory roles of rGSTO2 protein in murine macrophages in vitro were further explored. The results revealed that the GSTO2 gene encodes 254 amino acids, which harbor the characteristic N-terminal domain (βαβαββα) and C-terminal domain (α-helical) of the cytoplasmic GST superfamily. GSTO2 was mainly expressed in F. hepatica vitelline follicles, intestinal tract, excretory pores and vitelline cells, with thioltransferase and dehydroascorbate reductase activities. Moreover, rGSTO2 protein could be taken up by murine macrophages and significantly inhibit the viability of macrophages. In addition, rGSTO2 protein could significantly promote apoptosis and modulate the expression of cytokines in macrophages. These findings suggested that F. hepatica GSTO2 plays an important role in modulating the physiological functions of macrophages, whereby this protein might be involved in immunomodulatory and anti-inflammatory roles during infection. This study provided new insights into the immune-evasion mechanism of F. hepatica and may contribute to the development of a potential anti-inflammatory agent.