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During the past decades, glacier mass loss is becoming increasingly significant worldwide but knowledge about the acceleration is still limited despite its potentially profound impacts on sea level rise, water resources availability and glacial hazards. In this study, we analyzed the acceleration of glacier mass loss based on in-situmeasurements and on the latest compilation dataset of direct and geodetic observations for the period 1961–2016. The results showed that the rate of glacier mass loss has increased worldwide during the past decades. At the global scale, the rate of glacier mass loss has been accelerating at 5.76±1.35 Gt a−2as well as 0.0074±0.0016 m w.e.a−2on mass balance (refer to the area-averaged mass change value) during the whole period. At regional scales, for mass change rate, the heavily glacierized regions excluding Antarctic and Subantarctic exhibited a larger acceleration compared to other regions. The highest acceleration of mass change was found in Alaska glaciers (1.33±0.47 Gt a−2) over the full period. As for mass balance, high acceleration occurred on the regions with small glaciers as well as on the heavily glacierized regions. Central Europe exhibited the highest acceleration (0.024±0.0088 m w.e.a−2) during 1961–2016. High level of consistency between the acceleration and temperature implies that climate warming had a significant effect on the accelerating of glacier mass loss. Moreover, acceleration of the contribution from the Greenland ice sheet (0.028 to 0.070 mm a−2) and Antarctic ice sheet (0.023 to 0.058 mm a−2) to sea level rise exceeds acceleration of the contribution from global glaciers (0.019±0.013 mm a−2). These results will improve our understanding of the glacier retreat in response to climate change and provide critical information for improving mitigation strategies for impacts that may be caused by glacier melting.

The major obstacles for the efficacy of tumor immunotherapies are their immune-related systemic adverse events. Therefore, tumor tropism property and pro-inflammatory ability of mesenchymal stem cells (MSCs) could be utilized in combination to potentiate local immunity for cancer eradication. We previously observed that MSCs with the type III histone deacetylase silent information regulator 2 homologue 1 (Sirt1) overexpression displayed a pro-inflammatory capacity. However, the anti-tumor effect of Sirt1-overexpressing MSCs and the role of Sirt1 in regulating the pro-inflammatory capacity of MSCs still need to be clarified. In this study, utilizing the hepatic metastasis model of colorectal carcinoma, we demonstrated that Sirt1-overexpressing MSCs significantly exerted anti-tumor activity through increasing the number of CD8+T cells. Furthermore, Sirt1 did not affect chemokine secretion in MSCs induced by inflammatory cytokines, but impaired the immunosuppressive ability of MSCs through suppressing inflammatory cytokine-stimulated inducible nitric oxide synthase (iNOS) production via deacetylating p65. iNOS overexpression negated the anti-tumor effect of Sirt1-overexpressing MSCs. Collectively, our data defined Sirt1 as the critical regulator for modulating the pro-inflammatory ability of MSCs, and they suggested that Sirt1-overexpressing MSCs secreting chemokines but little iNOS under the inflammatory milieu were capable of attracting immune cells to close proximity without suppressing their proliferation, thereby achieving a potent anti-tumor effect.

Water storage has important significance for understanding water cycles of global and local domains and for monitoring climate and environmental changes. As a key variable in hydrology, water storage change represents the sum of precipitation, evaporation, surface runoff, soil water and groundwater exchanges. Water storage change data during the period of 2003–2008 for the source region of the Yellow River were collected from Gravity Recovery and Climate Experiment (GRACE) satellite data. The monthly actual evaporation was estimated according to the water balance equation. The simulated actual evaporation was significantly consistent and correlative with not only the observed pan (20 cm) data, but also the simulated results of the version 2 of Simple Biosphere model. The average annual evaporation of the Tangnaihai Basin was 506.4 mm, where evaporation in spring, summer, autumn and winter was 130.9 mm, 275.2 mm, 74.3 mm and 26.1 mm, and accounted for 25.8%, 54.3%, 14.7% and 5.2% of the average annual evaporation, respectively. The precipitation increased slightly and the actual evaporation showed an obvious decrease. The water storage change of the source region of the Yellow River displayed an increase of 0.51 mm per month from 2003 to 2008, which indicated that the storage capacity has significantly increased, probably caused by the degradation of permafrost and the increase of the thickness of active layers. The decline of actual evaporation and the increase of water storage capacity resulted in the increase of river runoff.

Hypoxia commonly exists in solid tumors. In this adverse condition, adaptive responses including autophagy are usually provoked to promote cell survival. In our study, autophagy, a lysosomal-mediated degradation pathway, is demonstrated a protective way to make hepatocellular carcinoma cells be resistant to chemotherapy under hypoxia. Compared with normoxia, chemotherapeutic agents-induced cell death under hypoxia was significantly decreased, as a result of the reduced apoptosis. However, when autophagy was inhibited by 3-MA or siRNA targeted Beclin 1, this reduction was reversed i.e. chemoresistance was attenuated, which means autophagy mediates the chemoresistance under hypoxia. In conclusion, autophagy decreases hepatoma cells sensitization to chemotherapeutic agents by affecting their apoptotic potential.

Daily floods including event, characteristic, extreme and inundation in the Lancang‐Mekong River Basin (LMRB), crucial for flood projection and forecasting, have not been adequately modeled. An improved hydrological‐hydrodynamic model (VIC and CaMa‐Flood) considering regional parameterization was developed to simulate the flood dynamics over the basin from 1967 to 2015. The flood elements were extracted from daily time series and evaluated at both local and regional scales using the data collected from in‐situ observations and remote sensing. The results show that the daily discharge and water level are both well simulated at selected stations with relative error (RE) less than 10% and Nash‐Sutcliffe efficiency coefficient (NSE) over 0.90. Half of the flood events have NSEexceeding 0.76. The peak time and flood volume are well reproduced while both peak discharge and water level are slightly underestimated. The results tend to worsen when the characteristics of flood events are extended to annual extremes. These extremes are generally underestimated with NSEless than 0.5 but REis within 20%. The simulated rainy season inundation area generally agrees with observations from remote sensing, with about 86.8% inundation occurrence frequency captured within the model capacity. Ignoring the regional parameterization and reservoir regulation can both deteriorate flood simulation performance at the local scale, resulting in lower NSE. Specifically, systematically higher water levels and up to 27% overestimation of peak discharge are found when ignoring regional parameterization, while ignoring reservoir regulation would cause up to 23% overestimation for flood extremes. It is expected that these findings would contribute to the regional flood forecasting and flood management. An improved hydrodynamic module with regional parameterization to enhance sub‐basin physical representation was developedDaily floods were modeled with relative error no more than 20% and NSEover 0.90 at selected stationsFlood simulation without regional parameterization or reservoir regulation shows less satisfactory performance with lower NSE An improved hydrodynamic module with regional parameterization to enhance sub‐basin physical representation was developed Daily floods were modeled with relative error no more than 20% and NSEover 0.90 at selected stations Flood simulation without regional parameterization or reservoir regulation shows less satisfactory performance with lower NSE