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Plant uptake consumed about 45% of inputs, primarily in the low-lying valley bottom areas and the plain covered by relatively thick soils. Thus, a large amount of N released from soil reservoirs to the epikarst (via fractures or sinkholes) is then exported to the underground channel in the limestone area to the south. This N draining into groundwater could lead to extensive, potentially long-term contamination of the karst system. Therefore, improving the efficiency of fertilization and agricultural management in valleys/depressions is an urgent need to reduce N losses and contamination risk.Haze is identified via different methods using hourly visibility, relative humidity (RH) and PM2.5 mass concentration observations collected from 2013 to 2018 at 502 stations in China. An inter-comparison of a new haze identification method (MGB) and other currently used methods (M80 and M90) is performed in this research. Compared with other methods, the MGB method has an advantage in the expression of fine particle pollution characteristics, especially in high humidity areas. The mean value of the correlation coefficient of the daily mean PM2.5 and daily haze hour obtained by MGB in China is 0.69 which is higher than the correlation coefficients of the daily mean PM2.5 and haze hour identified by the other two methods. Compared with M80, the haze identified by MGB and M90 is less influenced by daily or monthly variations of RH. Approximately 75% of haze occurs when the RH is exceeds 60% or the PM2.5 mass concentration is below 105 μg/m3 over China, no matter which haze identification method is used. Haze has obvious regional distribution characteristics and is relatively higher in Beijing-Tianjin-Hebei and its surrounding areas, and the middle and lower reaches of the Yangtze River. The 6-year mean annual total haze identified by the MGB method is 1167 h for mainland China. Compared with MGB, M80 underestimates the haze hour by -34%, and M90 produces a smaller positive overestimation by 18%. The annual total haze hour of China and its three major economic regions shows significant decreasing trends regardless of the identification method used. BGB324 Axl inhibitor Daily variation of haze is obtained in this research via automatic visibility measurement. The daily cycles of haze hour identified by MGB and M90 are similar, whereas that identified by M80 behaves differently affected by daily variation of RH. Haze hour is high in winter and low in summer.Nuclear pollution intertwined accidental irradiation not only triggers acute and chronic radiation syndromes, but also endangers embryonic development in sight of uncontrollable gene mutation. link2 Metformin (MET), a classic hypoglycemic drug, has been identified to possess multiple properties. In this study, we explored the radioprotective effects of MET on the developmental abnormalities and deformities induced by irradiation among three "star drugs". Specifically, zebrafish (Danio rerio) embryos exposed to 5.2 Gy gamma irradiation at 4 h post fertilization (hpf) showed overt developmental toxicity, including hatching delay, hatching rate decrease, developmental indexes reduction, morphological abnormalities occurrence and motor ability decline. However, MET treatment erased the radiation-induced phenotypes. In addition, MET degraded inflammatory reaction, hinders apoptosis response, and reprograms the development-related genes expression, such as sox2, sox3, sox19a and p53, in zebrafish embryos following radiation challenge. Together, our findings provide novel insights into metformin, and underpin that metformin might be employed as a promising radioprotector for radiation-induced early developmental toxicity in pre-clinical settings.Increasing soil organic carbon (SOC) can improve the capacity of agricultural systems to both adapt to and mitigate climate change. Despite its importance, the current understanding of the magnitude or even the direction of SOC change in agricultural landscapes is limited. While changes in land use/land cover (LULC) and climate are among the main drivers of changes in SOC, their relative importance for the spatiotemporal assessment of SOC is unclear. This study evaluated LULC and SOC dynamics using archived and recent soil samples, remote sensing, and digital soil mapping in the Lower Fraser Valley of British Columbia, Canada. We combined both pixel- and object-based analysis of Landsat satellite imagery to assess LULC changes from 1984 to 2018. We achieved an overall accuracy of 81% and kappa coefficient of 0.77 for LULC classification using a random forest model. For predicting SOC for the same time period, we applied soil and vegetation indices derived from Landsat images, topographic indices, historic soil survey variables, and climate data in a random forest model. The SOC prediction of 2018 resulted in a coefficient of determination (R2) of 0.67, concordance correlation coefficient (CCC) of 0.76, and normalized root mean square error (nRMSE) of 0.12. For 1984, the SOC prediction accuracies were 0.46, 0.58, and 0.18 for R2, CCC, and nRMSE, respectively. We detected SOC loss in 61%, gain in 12%, while 27% remained unchanged across the study area. Although we detected large losses of SOC due to LULC change, the majority of the SOC losses across the landscape were attributed to areas that were remained in the same type of agricultural production since 1984. Climate variability did not, however, have a strong effect on SOC changes. These results can inform decision making in the study area to support sustainable LULC management for enhancing SOC sequestration.The wide applications of rare earth oxide nanoparticles (REO NPs) in various fields and their subsequent release into the environment have attracted the research of their effects on organisms. In this study, the toxicity of yttrium oxide (Y2O3) NPs to tobacco BY-2 cells was evaluated and the importance of phosphate in the medium on the toxicity of Y2O3 NPs was revealed. 50 mg L-1 Y2O3 NPs induced 52.4% cellular growth inhibition after 24-h exposure. Phosphate inhibited the release of Y3+ from Y2O3 NPs from 6.00 to 0.04 mg L-1 at 24 h, thus reduced the toxicity of Y2O3 NPs. The surface charge of Y2O3 NPs changed from 24.0 mV (in deionized water) to -7.6 mV (in phosphate solution), which induced the aggregation of Y2O3 NPs. The change of surface properties reduced the direct nanotoxicity of Y2O3 NPs. High-resolution transmission electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy, and X-ray diffraction results demonstrated that phosphate transformed the surface of Y2O3 NPs to amorphous YPO4. This surface transformation decreased phosphate concentration in the medium. The dialysis membrane encapsulation experiment further identified the contribution percentage of direct nanotoxicity and indirect toxicity (i.e., phosphate depletion) of Y2O3 NPs to tobacco BY-2 cells in the presence of phosphate to be 68.3% and 31.7%, respectively. This study highlights the significant role of phosphate in altering the environmental behavior and toxicity of REO NPs.Variability of soil properties within large-scale fields not only exists in the horizontal domain, but also in the vertical direction, causing spatial variability in yield. Three yield zones were delineated based on measured yield in 2017 and 2018 within a large field in northwest China. The Soil Water Heat Carbon Nitrogen Simulator (WHCNS) model was calibrated and used to simulate yield, nitrogen uptake (Nu), water use efficiency (WUE), fertilizer N (nitrogen) use efficiency (FNUE), deep percolation (DP), nitrate leaching (NL) and residual nitrate (RN) at each sampling point in different yield zones. Based on the simulations, there were significant differences in Nu, WUE, FNUE, DP, NL and RN in 0-100 cm and 100-160 cm soil layers among the three yield zones. DP, NL and RN in the layers were strongly determined by the interaction of zone and year (p less then 0.05), thus yielding consistent patterns mainly determined by soil properties and meteorological factors. The modelled ranges of DP, NL, and RN (0-160 cm) were 25-119 mm, 15-94 kg ha-1, and 178-476 kg·ha-1 respectively, across the field. Soil texture in the maize main root zone (0-100 cm) has a great influence on yield and Nu, and in the 100-160 cm layer upon DP and NL. RN was abundant after harvest and should be taken into account to determine the nitrogen fertilization demand for the following crop. The study showed that the process of delineating zones can be based on historical yield, making it feasibly easier than mapping soil properties. In view of the fact that there were large losses of water and nitrogen with uniform irrigation and fertilization management, the effects of vertically variable soil properties should be considered in future precision agriculture research, to achieve higher economic benefits and utilization efficiency.Background Previous climate change temperature-related health studies have been performed mostly in western countries with relatively cooler temperatures than the Gulf region. Regions that are inherently hot, like Kuwait, are witnessing soaring temperatures unlike ever before. Meanwhile, Kuwait and other Gulf countries are unique in their demographic profiles due to the large number of non-national migrant workers. Objective To examine the associations of hot and cold temperature extremes on the risk of mortality across gender, age groups and nationality in Kuwait. Methods We investigated daily variations of all-cause non-accidental and cardiovascular mortality death counts and ambient temperatures from 2010 to 2016 in a time-series design using a negative binomial distribution. The temperature lag was modeled with distributed lag non-linear models. link3 Results A total of 33,472 all-cause non-accidental deaths happened during the study period. For the extreme hot temperatures and over the entire lag period, compangs could carry a potential for broader insight into similar hyper-arid and hot regions.Volatile organic compounds (VOCs) are precursors for ozone (O3) and secondary particulate matter, which contribute to asthma and cardiovascular diseases. With the technology development of hydraulic fracking, the United States experienced a shale gas boom in the last decade while the public raised concerns about the potential health impacts of co-emitted VOCs and other airborne pollutants. National Energy Technology Laboratory conducted stationary trailer-based ambient monitoring to study the sources of VOCs in Maryland, where the state enacted a moratorium on unconventional natural gas extraction. The campaign had two periods, May to August 2014 (summer) and November 2014 to February 2015 (winter). Ethane was the most abundant VOC, averaging 12.3 ppb (SD = 15.7 ppb) in summer and 21.7 ppb (SD = 21.6 ppb) in winter. The seasonal variation of VOCs indicated different source strengths. The sampling region was in the nitrogen oxides (NOx) limited regime for O3 production, and the O3 concentrations were sensitive to VOC/NOx ratios in the early mornings. We derived a six-factor profile using positive matrix factorization motor vehicles, industrial, biogenics, coal burning, fugitive and evaporative, and ozone secondary. The fugitive and evaporative factor explained 44.5% of total VOCs, and the motor vehicles factor followed second with 15.5%. Oil and gas activities had a considerable impact on the abundance of VOCs in this region.