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Background: To investigate the associations of serum vitamin D and Fok I polymorphism of its receptor (VDR) with unexplained recurrent spontaneous abortion (URSA).

Abrupt permafrost thaw accelerates the decomposition of soil organic carbon and might double the warming caused by the carbon release. However, the influence of thaw slump evolution on carbon dioxide (CO2) emission rates and its drives remains unclear, which induces large uncertainties in the prediction of permafrost carbon‐climate feedback. Here we collected soil samples in the thaw slump landscapes that happened 1–23 years ago on the northern Qinghai‐Tibet Plateau (QTP) and measured the CO2 release rates using a 189‐day aerobic laboratory incubation in the dark. The incubation results showed that thaw slump occurred 23 years ago reduced soil CO2–C release by 57 ± 19% compared with the undisturbed area. The relative contribution of O‐alkyl C and microbial abundance decreases with the thaw slump initiation time lengthens. We illustrate that soil carbon quality and microbial communities uniquely explained 41% and 13% of the variation in CO2–C release, respectively. We preliminary estimate that the carbon release for thaw slump landscapes on the QTP may be overestimated by approximately 50% if the declining soil CO2–C release is without consideration. Our study highlights the CO2–C release would decrease with the stability of thaw slumps on the warming and wetting QTP, which may weaken the mountain permafrost carbon‐climate feedback. Plain Language Summary: Rapid warming of permafrost regions leads to the widespread development of thaw slumps and accelerates the decomposition and release of soil organic carbon. Yet, how the evolution of thaw slump affects CO2 release remains unclear. We found that CO2 release gradually decreased with the thaw sequence. Labile carbon (O‐alkyl C) proportion and microbial abundance declined along the thaw sequence, while resistant carbon (alkyl C) proportion increased. Soil carbon quality and microbial communities are important factors controlling CO2 release. Applying the results to the entire Tibetan Plateau, we find that permafrost carbon emissions would be overestimated by approximately 50% if the declining soil CO2 release of stabilized thaw slump is without consideration. Our findings suggest that stable thaw slump can weaken CO2 release. Therefore, the assessment of mountain permafrost carbon feedback needs to consider the effect of thaw slump evolution. Key Points: Soil CO2 release was reduced by 57% in areas that collapsed for 23 years compared to the control areasThaw slump leads to a large decrease in O‐alkyl C and soil microbial abundanceSoil carbon quality and microbial communities exert the controls of 41% and 13% over CO2 release, respectively [ABSTRACT FROM AUTHOR]

The interpretation and understanding of the relationship between Middle to Late Holocene climate change in monsoon margins of northwest China with the westerlies and Asian monsoon (AM) remain controversial. Here we present a new multi-proxy sedimentary dataset from the Heihe River basin in the middle part of the Hexi Corridor on the northern margin of the Qinghai-Tibet Plateau (QTP), which is a sensitive zone for the interaction between the westerlies and AM. Fluctuations in grain size, δ13Corg, δ18O, magnetic susceptibility, total organic carbon, total nitrogen, and C/N ratio document regional lake and climate evolution since 5334 cal yr BP. Results show that climate conditions on the millennial timescale are humid in the late Middle Holocene (MH) and dry to wet in the Late Holocene (LH). Combined with the multi-model ensemble simulation from PMIP3-CMIP5, high lake levels and wetter climate in the late MH are closely linked to the strengthening Asian summer monsoon. Simultaneously, the slight wetting trend since the late LH may be the superimposing effect of enhanced westerlies and the weakening Asian winter monsoon. These findings can provide insights into the interpretation of the interaction between the westerlies and AM during the Holocene in East Asia. [ABSTRACT FROM AUTHOR]

The production, transport, and deposition of dust has profound impacts and feedbacks on the regional and global environments. In parallel, the Tibet Plateau (TP) plays an important role in East Asian and global climate systems. Previous studies have shown that the dust can reach the plateau by long-distance transport from the westerlies and by short-distance transport from regional weathering. Here we present three new datasets in the Qilian Mountains of the northern TP, including two mountainous aeolian sedimentary sequences and a surface sample dataset. Proxies include grain size, magnetic susceptibility, mineral composition, total organic carbon, and total nitrogen. Data from surface samples indicate spatial gradient effects in altitude (from low to high) and latitude (from north to south), suggesting dust transport from the Gobi Desert to the plateau. The synthetic analysis of two aeolian sedimentary sequences and paleoclimate simulation data reveals that the northern TP can be a dust transport channel controlled mainly by the Asian winter monsoon and less influenced by the westerlies. [ABSTRACT FROM AUTHOR]