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Geochronological dating of detrital minerals from sedimentary rocks can provide invaluable records of the erosional and unroofing history of orogenic systems and link specific sources with their sinks in sedimentary basins. Aiming to establish a better understanding of the thermal and erosional evolution of the East Kunlun Orogenic Belt (E‐KOB), northern Tibet Plateau during the Mesozoic, integrated detrital U–Pb zircon, and 40Ar/39Ar muscovite dating was applied to Triassic and Jurassic strata in the southern E‐KOB in this study. Detrital U–Pb zircon ages of clastic rocks from Triassic and Jurassic formations show major age populations at 2,600–2,200 Ma, 2,000–1,700 Ma, 1,000–600 Ma, 530–340 Ma, and 320–220 Ma, while the 40Ar/39Ar dating of detrital muscovite yield dominantly Devonian ages with uniform early‐middle Devonian peak ages (380–405 Ma). Our new detrital U–Pb zircon and 40Ar/39Ar muscovite ages, combined with the previous palaeocurrent data and comparison with published U–Pb zircon, and 40Ar/39Ar muscovite ages of potential source areas, suggest that the E‐KOB was the major source for Triassic and Jurassic strata in the southern East Kunlun. Devonian detrital muscovite 40Ar/39Ar ages of the Triassic and Lower Jurassic strata are consistent with the age of syn‐ and post‐collisional magmatic activity in E‐KOB related with the post‐collisional thermal relaxation after closure of the Qimantagh back‐arc basin. The Lower Triassic sedimentary deposits were associated with the subduction of the Kunlun Ocean, which is part of the Palaeo‐Tethys Ocean. The E‐KOB‐derived material in Upper Triassic and Lower Jurassic formations implies that significant surface uplift, unroofing and erosion occurred during the Late Triassic and continued into the Early Jurassic in the East Kunlun region. [ABSTRACT FROM AUTHOR]

In the present study, we used the eddy covariance method to measure CO2 exchange between the atmosphere and an alpine shrubland meadow ecosystem (37°36’N, 101°18’E; 3 250 m a.s.l.) on the Qinghai-Tibetan Plateau, China, during the growing season in 2003, from 20 April to 30 September. This meadow is dominated by formations ofPotentilla fruticosaL. The soil is Mol-Cryic Cambisols. During the study period, the meadow was not grazed. The maximum rates of CO2 uptake and release derived from the diurnal course of CO2 flux were -9.38 and 5.02μmol·m-2·s-1, respectively. The largest daily CO2 uptake was 1.7 g C·m-2·d-1 on 14 July, which is less than half that of an alpineKobresiameadow ecosystem at similar latitudes. Daily CO2 uptake during the measurement period indicated that the alpine shrubland meadow ecosystem may behave as a sink of atmospheric CO2 during the growing season. The daytime CO2 uptake was correlated exponentially or linearly with the daily photo synthetic photon flux density each month. The daytime average water use efficiency of the ecosystem was 6.47 mg CO2/g H2O. The efficiency of the ecosystem increased with a decrease in vapor pressure deficit.(Managing editor: Ya-Qin HAN) [ABSTRACT FROM AUTHOR]

Abstract: Association between genes influencing alcohol metabolism and alcohol use disorders (AUD) has been extensively studied, but the effect of interactions between these genes and AUD have rarely been tested. Our previous case–control study in a Tibetan population noted that the positive association between *c2 allele of cytochrome P4502E1 (CYP2E1) gene and AUD might only exist in males who are homozygotes for *1 alleles of aldehyde dehydrogenase-2 (ALDH2) and alcohol dehydrogenase-1B (ADH1B) genes, but this interaction did not reach statistical significance. Using the same set of data, the present study was aimed at exploring interactions between these genes and quantitative alcohol-related-trait scores (QARTs), and whether these are influenced by gender. The sample included 383 AUD cases with the alcohol use disorders identification test (AUDIT) score ≥10 and 350 normal controls with the AUDIT score ≤5. QARTs were measured using three factors from AUDIT. Possible associations of QARTs with interactions among genotypes of ALDH2*1/*2, ADH1B*1/*2 and CYP2E1*c1/c2* and sex were analyzed in AUD cases and normal controls separately. The subjects with *2 alleles of ALDH2 or/and ADH1B had significantly lower scores of alcohol intake among controls but had significantly higher scores of alcohol related problems among cases. The score of alcohol intake in male cases who are homozygous for ALDH2*1 and ADH1B*1 and with CYP2E1*c2 allele was significantly higher than that of other cases. These findings suggest that interactions between genes influencing alcohol metabolism are influenced by gender and might affect QARTs differently between the milder-/non-drinkers and AUD cases. [Copyright &y& Elsevier]