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It is generally accepted that extensive and intensified aridity in inland Asia began in the mid-Miocene as a result of global cooling. We present new data from mid-Miocene drill cores in the Qaidam Basin that suggest a new view about the timing, depositional characteristics and driving force of this change in climate. To understand the intensified aridity in the Qaidam Basin, we investigated the carbon and oxygen isotopes and magnetic susceptibility of 400 m of successive drill cores and analyzed 2600 m of gamma ray logging data from the whole borehole. By comparing the gamma ray logging data and global temperatures, we easily identified the Middle Miocene Climatic Optimum and Middle Miocene Climate Cooling in this borehole. The positively biased oxygen isotopes and the negative shift in magnetic susceptibility from the fine-grained mixed sediments and carbonate rocks showed a climate drying within the Middle Miocene Climatic Optimum. A decrease in the interlayers of algal/oolitic limestone and an increase in the interlayers of dolostone marked this drying event as slightly earlier than 15.3 Ma. The mountain-building spanning the northern margin of the Tibetan Plateau changed the local precipitation patterns and probably led to the intensified aridity in inland Asia as early as the Middle Miocene Climatic Optimum. [ABSTRACT FROM AUTHOR]

Background: Despite substantial attention paid to the epidemic of nonalcoholic fatty liver disease (NAFLD) in adults, data on the burden and sexual dimorphism of NAFLD in Asian children have not yet been synthesized. Methods: We conducted a literature search of 735 references up to April 2021. Pooled analyses, stratified analyses and meta‐regression were all performed. Results: Thirty‐three study populations were finally included. Nine of them comprising 20 595 children showed an overall NAFLD prevalence of 5.53% (95% CI 3.46%‐8.72%), in which, 36.64% (95% CI, 27.99%‐46.26%) NAFLD subjects had elevated levels of ALT. The prevalence rate of NAFLD increased about 1.6‐fold from 2004 to 2010 to the last decade. Male predominant trends were observed in paediatric NAFLD (boys: 8.18%, 95% CI 4.93%‐13.26%; girls: 3.60%, 95% CI 1.60%‐7.87%). Moreover, meta‐analysis showed that after 10 years of age, boys were more prone to have NAFLD than girls (OR = 1.75; P =.0012). In addition, the pooled prevalence of NAFLD increased sequentially in normal‐weight (1.49%, 95% CI 0.88%‐2.51%, n = 2610), overweight (16.72%, 95% CI 7.07%‐34.65%, n = 1265) and obese children (50.13%, 95% CI 41.99%‐58.27%, n = 6434 individuals). After full covariate adjustment, the multivariate meta‐regression also showed that boy percentage (P =.0396) and body mass index (P <.0001) were positively correlated with prevalent NAFLD. Conclusions: In Asia, paediatric NAFLD is becoming prevalent over the recent decades, particularly among obese children and boys after 10 years old. The hormonal and chromosomal origins of paediatric NAFLD dimorphism need further investigation. [ABSTRACT FROM AUTHOR]

Fine-grained sediment deposition is widely distributed in lacustrine and marine facies and significant for petroleum geology. However, the causes of fine-grained sediment deposition remain controversial. In this study, we examine the cause of fine-grained sedimentation in the Neogene saline lacustrine Qaidam Basin, and propose a new insight into the sedimentary process for fine-grained sediments. Various sedimentary structures identified from the fine-grained sediments such as erosional structures with lag deposits, hummocky cross-stratification (HCS)-like structures, asymmetrical ripples, or sandy ball-and-pillow structures, are generated by winter storms. These winter storms are related to the winter winds that cause eolian sedimentation in Asia. Abundant detrital material may be rapidly transported into lakes by winter storms, favoring extensive terrigenous detrital deposition in the lacustrine basin, hardly controlled by the division of sedimentary facies and topographical differentiation. The genetic features and shallow-water origin with wind and fluvial–lacustrine source-to-sink processes, may be the main reason for the poor hydrocarbon potential of the Neogene fine-grained sediments in the Qaidam Basin. • Our findings identify the winter storm is origin of the Neogene storm activity in inland Asia. • The early Neogene Qaidam Basin is a wind and fluvial-lacustrine source-to-sink basin. • The wind and fluvial-lacustrine source-to-sink processes are the cause of the poor hydrocarbon potential. [ABSTRACT FROM AUTHOR]

Desertification and microplastic pollution are major environmental issues that impact the function of the ecosystem and human well-being of drylands. Land desertification may influence soil microplastics' abundance, transport, and distribution, but their distribution in the dryland deserts of Central Asia's Amu Darya-Aral Sea basin is unknown. Here, we investigated the abundance and distribution of microplastics in dryland desert soils from the Amu Darya River to the Aral Sea basin in Central Asia at a spatial scale of 1000 km and soil depths ranging from 0 to 50 cm. Microplastics were found in soils from all sample locations, with abundances ranging from 182 to 17841 items kg -1 and a median of 3369. Twenty-four polymers were identified, with polyurethane (PU, 37.3%), silicone resin (SR, 17.0%), and chlorinated polyethylene (CPE, 9.8%) accounting for 64.1% of all polymer types. The abundance of microplastics was significantly higher in deep (20-50 cm) soils than in surface (0-5, 5-20 cm) soils. The main morphological characteristics of the observed microplastics were small size (20-50 μm) and irregular particles with no round edges (mean eccentricity 0.65). The abundance was significantly and positively related to soil EC and TP. According to the findings, desertification processes increase the abundance of microplastic particles in soils and promote migration to deeper soil layers. Human activities, mainly grazing, may be the region's primary cause of desertification and microplastic pollution. Our findings provide new information on the diffusion of microplastics in drylands during desertification; these findings are critical for understanding and promoting dryland plastic pollution prevention and control., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Competing Interests: Conflict of interest The authors declare that they have no conflict of interest.