BACKGROUND Zinc is one of the vital micronutrients required through various developmental stages in animals. Zinc transporter-1 (ZnT1; Slc30a1) is essential in vertebrates for nutritional zinc uptake and cellular zinc extrusion. Knockout of ZnT1 is lethal in vertebrates and there are therefore few functional studies of this protein in vivo. METHODS In the present study we characterised the embryonic development in a zebrafish Znt1a mutant (Znt1asa17) which is lacking the last 40 amino acids of Znt1a as generated by TILLING. In parallel experiments, we compared the development of a zebrafish embryo Znt1a morphant (Znt1aMO) which was generated by knockdown of Znt1a using morpholino-modified oligonucliotides. RESULTS The homozygous Znt1asa17 embryo is viable, but displays a subtle phenotype informing on the biological roles of Znt1a. The Znt1asa17 fish have delayed development, including attenuated epiboly. They further show a decrease in phosphorylated extracellular signal-regulated kinases 1 and 2 (pERK1/2), retarded yolk resorption, and impaired clearance of free Zn2+ from the vitelline fluid and its storage in hatching gland cells. All these aberrations are milder versions of those observed upon knockdown of Znt1a by morpholinos. Interestingly, the phenotype could be rescued by addition of the cell-permeable zinc chelator, N,N,N',N'-tetrakis(2-pyridinylmethyl)-1,2-ethanediamine (TPEN) to the incubation medium and was aggravated by addition of zinc(II). Thus, the Znt1asa17 mutant has a reduced ability to handle zinc and can be characterised as a hypomorph. CONCLUSION This study is the first to show that the last 40 amino acids of Znt1a are of importance for its role in zinc homeostasis and ability to activate the MAPK/ERK pathway contrary to what was previously thought. The recent acute evolution of cropland structure in Cold China could lead to rapid rice paddy expansion, potentially altering land-surface thermal processes and influencing climate. To address the issue, this study investigated the changes in cropland type, land-surface temperature (LST) and heat fluxes in the agricultural region of Cold China during 2000-2015 based on time-series of land-use data and MODIS LST product, using the split-window algorithms (SWA) model and the pixel component arranging and component algorithm (PCACA). The investigation revealed large-scale land transformation from rain-fed farmland to paddy field in Cold China during 2000-2015. Compared to the rain-fed farmland, lower LST was observed in paddy field throughout crop growing seasons, with the highest LST threshold found in June (7.17 ± 1.05 °C) and the lowest value found in August (1.04 ± 0.35 °C). The cooling effect of paddy-field ranged from 0.59 ± 0.06 °C, 0.77 ± 0.07 °C, and 1.08 ± 0.08 °C for the low-, medium-, and high-density paddies, respectively. Compared to other months, stronger cooling effect was found in May and June. Further analysis showed the conversion of a rain-fed farmland to paddy field reduced the sensible heat flux and soil heat flux by 52.94 W/m2 and 15.26 W/m2, respectively, while increased the latent heat flux and net radiation by 115.66 W/m2 and 47.34 W/m2, respectively. The findings from this study indicated the changes in cropland structure and management regime (e.g., irrigation) could profoundly modify land-surface thermal processes and local/regional climate, interfering the signals from global warming. Therefore, instrumental climate data that collected from areas experienced large-scale conversion between rain-fed and paddy farmland should be carefully screened and corrected to prevent land-use induced biases. Treating wastewater at low temperatures has always been challenging. In this study, an anoxic filter (ANF)/multi-stage waterwheel driving rotating biological contactors (ms-wdRBCs) device was investigated as a potential solution for treatment of low-strength domestic wastewater at low temperatures (6-18 °C). Parameters, including the recirculation ratio (RR) and hydraulic retention time (HRT), were regulated to identify the optimum operating conditions. Using the optimum parameters of 200% RR, 10.67 h HRTANF, and 1.33 h HRTwdRBC, 75.37% ± 4.43% COD, 44.81% ± 3.67% TN, 75.05% ±1.86% NH4+-N, and 35.46% ± 4.87% TP were removed. The microbial communities in eight different sections of the device were investigated through the 16s rRNA analysis. The microbial results helped to explain the device performance. Denitrification-related bacteria were present in great abundance in both the ANF and the ms-wdRBCs. Anammox-related bacteria were also in significant abundance in ANF and some parts of ms-wdRBCs, which suggested a potential solution for improving the device performance by expanding the role of these anammox bacteria. Considering both the pollutant removal efficiency and investment costs, this device is acceptable as part of a low-strength domestic wastewater treatment solution at low temperatures. Frost as a kind of deposition plays an important role in the removal of atmospheric compounds. However, studies concerning frost in the atmospheric environment were rare although chemical composition in frost samples might be affected by the surrounding atmospheric environment. In this study, a total of 35 frost samples were collected by means of a homemade glass-plate frost condenser under severe polluted condition in the North China Plain (NCP) from Dec. 4, 2018 to Mar. 2, 2019. https://www.selleckchem.com/products/wnt-c59-c59.html The pH values and water-soluble ions (WSI) were conducted. The extremely high concentrations of WSI were found, which reflected the severe pollution significantly affecting the level of chemical composition in frost. The major ions were Ca2+, SO42- and HCO3- with averaged concentrations of 1242, 1143, 1076 μeq L-1, respectively. These ions were at least one order of magnitude higher than the previous frost studies. HCO3- was one of the most abundant components in frost. Its high proportion contributed to the ionic balance and led to the alkaline characteristic of frost. SO42- had the almost doubled ratio in frost compared with the concurrent PM2.5 samples. Different from the huge diversity of chemical components in PM2.5, the frost had similar ratio of WSI under great variety of PM2.5 concentrations. It proved that PM2.5 had less effect on the ratio of WSI in frost. Nutrient ions of NH4+, NO3- and K+ accounted for 13.9%, 5.4% and 1.6% of the total averaged concentrations, respectively. On average, per square meter soil would receive 563 μg nitrogen and 123 μg potassium nutrient during a frost night. High occult deposition flux of ions indicated the strong scavenging effect from the frost event. In addition, the occult deposition flux of SO42- was comparable to the dry deposition flux, further emphasizing frost process as a non-negligible atmospheric removal pathway of SO42-.