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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 CO2release 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. 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 CO2release remains unclear. We found that CO2release 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 CO2release. Applying the results to the entire Tibetan Plateau, we find that permafrost carbon emissions would be overestimated by approximately 50% if the declining soil CO2release of stabilized thaw slump is without consideration. Our findings suggest that stable thaw slump can weaken CO2release. Therefore, the assessment of mountain permafrost carbon feedback needs to consider the effect of thaw slump evolution. Soil CO2release 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 CO2release, respectively Soil CO2release was reduced by 57% in areas that collapsed for 23 years compared to the control areas Thaw slump leads to a large decrease in O‐alkyl C and soil microbial abundance Soil carbon quality and microbial communities exert the controls of 41% and 13% over CO2release, respectively

With a nearly 100% mortality rate, African swine fever (ASF) has devastated the pork industry in many countries. Without a vaccine in sight, mitigation rests on rapid diagnosis and immediately depopulating infected or exposed animals. Unfortunately, current tests require centralized laboratories with well-trained personnel, take days to report the results, and thus do not meet the need for such rapid diagnosis. In response, we developed a portable, sample-to-answer device that allows for ASF detection at the point of need in <30 min. The device employs droplet magnetofluidics to automate DNA purification from blood, tissue, or swab samples and utilizes fast thermal cycling to perform real-time quantitative polymerase chain reaction (qPCR), all within an inexpensive disposable cartridge. We evaluated its diagnostic performance at six farms and slaughter facilities. The device exhibits high diagnostic accuracy with a positive percent agreement of 92.2% and a negative percent agreement of 93.6% compared with a lab-based reference qPCR test.

The fluctuation of a single lake level is a comprehensive reflection of water balance within the basin, while the regional consistent fluctuations of lake level can indicate the change of regional effective moisture. Previous researches were mainly focused on reconstructing effective moisture by multiproxy analyses of lake sediments. We carried out a series of experiments, including a transient climate evolution model, a lake energy balance model and a lake water balance model to simulate continuous Holocene effective moisture change represented by variability of virtual lake level in East and Central Asia. The virtual lake level, area, water depth and salinity are not equivalent to actual values, but we estimated relative changes of the regional effective moisture. We also explored the driving mechanisms of effective moisture change in different geographical regions. Our results indicated that gradually falling effective moisture during the Holocene in northern China was due to the combined effects of high lake evaporation caused by longwave and shortwave radiation, and low precipitation caused by reductions of summer solar insolation. A decline in effective moisture through the Holocene in the Tibetan Plateau and southern Central Asia resulted from decreased precipitation because of the weakening of the Asian summer monsoon. Increased precipitation induced by the strengthening of the westerly circulation contributed to the effective moisture rise during the Holocene in northern Central Asia.

The multipotent cytokine granulocyte macrophage-colony stimulating factor (GM-CSF) is involved in particular in the physiological response to infection and in inflammatory responses. GM-CSF is produced by many cell types, including T lymphocytes responding to T-cell receptor activation and mantle zone B lymphocytes. B-cell receptor and T-cell receptor activation generates two major signals: an increase in intracellular Ca2+concentration and a protein kinase cascade. Previous studies have shown that the Ca2+/calmodulin-dependent phosphatase calcineurin mediates stimulation of GM-CSF transcription in response to Ca2+. In this study, we show that Ca2+signaling also regulates GM-CSF transcription negatively through Ca2+/calmodulin-dependent kinase II (CaMK II) phosphorylation of serines in the autoinhibitory domain for DNA binding of the transcription factor Ets1. Wild-type Ets1 negatively affects GM-CSF transcription on Ca2+stimulation in the presence of cyclosporin A, which inhibits calcineurin. Conversely, Ets1 with mutated CaMK II target serines showed an increase in transactivation of the GM-CSF promoter/enhancer. Moreover, constitutively active CaMK II inhibited transactivation of GM-CSF by wild-type Ets1 but not by Ets1 with mutated CaMK II sites. Mutation of CaMK II target serines in Ets1 also relieves inhibition of cooperative transactivation of GM-CSF with the Runx1/AML1 transcription factor. In addition, the Ca2+-dependent phosphorylation of Ets1 reduces the binding of Ets1 to the GM-CSF promoter in vivo.

Chemokine and antigen signals converge on an adaptor protein to enhance T cell activation.

Vesicles dynamically deliver the T cell adaptor protein LAT to sites of T cell signalosomes.