Mackinnonernstsen6350

Salmonella enterica is a major foodborne pathogen causing symptomatic diseases or asymptomatic infections in humans. To reveal the genetic difference of Salmonella strains from patients to that from asymptomatic people, we used CRISPR typing to analyze the phylogenetic relationship of 180 clinical strains during 2017-2018 in Jiangsu, China. The CRISPR typing divided these isolates into 76 CRISPR types with a discriminatory power of 97.6%. S. Typhimurium and its monophasic variants of 6 CRISPR types are the significant serotypes causing both human diseases and asymptomatic infection, while S. Enteritidis mainly resulted in diseases and shared one CRISPR type. The spacer HadB20 displayed as a new molecular marker to differentiate ST34-S. Typhimurium monophasic variant from ST19-S. Typhimurium. S. Derby, S. London, and S. Senftenberg frequently caused asymptomatic infection with diverse CRISPR types, while S. Mbandaka and S. Meleagridis, occasionally isolated from patients, had conserved CRISPR types. Additionally, 30 of 516 newly identified spacers showed homology to sequences in both plasmids and bacteriophages. Interestingly, some spacers from one serotype showed homology to the correspondent prophage or plasmid sequences in another serotype; and more than two spacers identified in one strain showed homology to the sequences located in the identical plasmids or phages, revealing the constant evolution of Salmonella CRISPR arrays during the interactions between bacteria and phages or plasmids.A series of nitrogen-doped carbon aerogels (NCAs) were obtained through phase reaction polymerization and different carbonization temperatures to enhance adsorption efficacy of hexavalent chromium (Cr[VI]) from wastewater significantly. Factors that influence adsorption properties of carbon aerogel microspheres toward Cr(VI), such as pH, adsorbent content, initial Cr(VI) concentrations, and coexisting anion, were investigated. Three isotherm (Langmuir, Freundlich, and Sips) and three kinetic (pseudofirst-order, pseudosecond-order, and Elovich) models were used to interpret the adsorption process. The adsorption capacity of Cr(VI) reached 180.62 mg·g-1, which was superior to that of most aerogel adsorbents. In addition to the adsorption effect, the XPS results also showed that N-containing groups on the NCA surface reduce the adsorbed Cr(VI) to the less toxic Cr(III). The prepared sorbent demonstrates a negligible loss in adsorption capacity after 6 cycles. NCAs show acceptable application prospects in selective removal of Cr(VI) ions.The radioactive nuclide 137Cs that was released during the Chernobyl accident in 1986 is still present in the environment of wide parts of Middle Europe. It causes internal radiation exposure of people who incorporate this radionuclide when eating contaminated food, in particular boar meat and certain kinds of wild mushrooms. This study investigates the exposure of German hunters and their family members, which are supposed to consume these kinds of food more frequently than the general population. For this purpose, the body activity of 137Cs was measured in 58 hunters and their family members mostly from Southern Germany and it was compared with body activities from 1729 measurements of 251 members of the general population. find more Significantly higher 137Cs body activities were found in the hunters and their family members compared to the references after matching both groups for sociodemographic factors and the time of the measurement (factor of 2.4 between the geometric means, p-value ≪ 0.001). Within the hunters and their family members, an adjusted exponential regression showed significant associations of the activity and of mushroom picking (factor 2.6, 95% confidence interval 1.5-4.6) and of the frequency of having boar meat as part of the diet (factor 1.4 per meal per week, 95% confidence interval 1.1-1.8). No significant association was found for the 137Cs surface contamination at the hunting grounds. Within families, mostly similar results were found in terms of activity concentrations. For the hunter with the highest measured activity (1050 Bq), an annual contribution to the effective dose of 35 μSv was calculated, showing that also in hunters and their family members 137Cs is expected to cause only small contributions to the total effective dose from environmental exposure.Parabens, benzophenone (BP)-type UV filters, triclosan (TCS), and triclocarban (TCC) are commonly used in personal care products. Human exposure to these compounds has received increasing concern because of their adverse health effects. However, the levels of these chemicals in paired urine and indoor samples have never been simultaneously measured. In this work, eight parabens, eight BP-type UV filters, TCS, and TCC were measured in paired urine and indoor dust samples collected from university students and their dormitories in South China. The target analytes were commonly measured in urine (71%-100%) and indoor dust (30%-98%), with median concentrations ranging from 0.16 ng/mL to 19.3 ng/mL in urine and from less then 0.01 ng/g to 3700 ng/g in indoor dust samples. Females had high levels of most of these target compounds, and gender-related differences were found in the levels of most target analytes. Positive correlations were found in the levels of methylparaben, ethyl paraben, benzophenone-3, and TCS between urine and indoor dust samples. This finding suggested that indoor dust is an important source for human exposure to these compounds. The estimated daily intake (EDI) of these analytes in paired samples was also evaluated. The median EDI-urine values of target analytes varied in the range of 4.02-59,280 ng/kg bw/day. Females had higher median EDI-urine values for most of target analytes than males. In addition, the median EDI-indoor dust values of most target analytes in dust from female dormitories were higher than those in dust from male dormitories. Indoor dust ingestion only had minor contribution ( less then 0.5%) to the total exposure. To the best of the authors' knowledge, this study is the first to simultaneously analyze the concentrations of parabens, BP-type UV filters, TCS, and TCC in the paired urine and indoor samples from university students in South China.The ultra-low emission retrofitting (ULE) in China's coal-fired power plants (CFPPs) enhances removal efficiencies of trace elements, which may increase their contents in fly ash and gypsum. However, their potential environmental risks in these wastes have been scarcely evaluated. Experiments indicated that the trace elements in fly ash and gypsum accounted for approximately 92.9-98.2% of the total outputs. Most trace elements in these wastes existed mainly as mobile/leachable forms, except for the Hg in fly ash (residual form). We comprehensively evaluated the potential environmental risks of trace elements in fly ash and gypsum from ULE CFPPs in China using a modified risk assessment approach that integrates a trace element enrichment model for waste, and chemical speciation datasets. We found that nationally, trace elements in gypsum represented low levels of potential risk, even after ULE. However, the potential moderate environmental risk of fly ash has aroused attention because of trace element pollution, where Hg and Cd contributed the major risks. The relatively high risks from fly ash are mainly distributed in Guangxi, Hunan and Hebei provinces. The disposal of fly ash in these areas should be given special attention in the future.Suppressing the formation of chlorinated aromatics (Cl-aromatics) by chemical inhibitors is an important measure to reduce dioxin emission from the solid waste incineration plants. In this study, we first investigated the reduction effect of a novel inhibitor sodium thiocyanate (NaSCN) on the emission of dioxins in 2 full-scale solid waste incineration systems. Injection of NaSCN solution into the higher temperature flue gas resulted in about 60% reduction in the concentration of total tetra- to octa-chlorinated dibenzo-p-dioxins and dibenzofurans in stack flue gas. The suppression effect was further verified by a laboratory study on the chlorination of naphthalene over model fly ashes with or without NaSCN addition. By characterizing the reaction products between NaSCN and key catalysts Cu and Fe chlorides, two main suppression mechanisms were proposed (i) reduction of highly active cupric chloride (CuCl2) and ferric chloride (FeCl3) to less active cuprous chloride (CuCl) and ferrous chloride (FeCl2), (ii) sulfidation of Cu chlorides. The laboratory study indicated that the unreacted NaSCN in the combustion flue gas could be mainly decomposed into Na2S, C3N4, Na2S2O3, NaS2, Na2SO4, CO2, SO2, NO2 and COS. These decomposition products are low toxic or can be effectively removed by the air pollution control devices. CAPSULE NaSCN suppressed the formation of chlorinated aromatics in combustion flue gas mainly through inducing the reduction of highly active Cu (II) and Fe (III) chlorides.Integrated studies about potentially toxic elements (PTEs) in sites near gold mining spoils, their contamination and human health risk, as well as remediation potential of native plants are limited. Therefore, our aim was to assess the human health risk of PTEs (Al, As, Cd, Cr, Cu, Fe, Ni, Pb, Ti, V, and Zn) in sites near an abandoned gold mine spoil in Ghana. We collected 52 soil samples near the mine spoil and from a natural forest, determined their total element contents, and calculated the soil contamination factor (CF), enrichment factor (EF), geo-accumulation index (Igeo) and the pollution load index (PLI). In addition, we calculated the human health risk of soil ingestion for adult males, females, and children using the hazard quotient (HQ) and hazard index (HI). We also assessed the phytoremediation potential of five native plants (Alchornea cordifolia, Chromolaena odorata, Lantana camara, Pityrogramma calomelanos- fern, and Pueraria montana) growing near the mine spoil, and calculated their transfer coefficient (TC) and translocation factor (TF). Total content of As (maximum 3144.0 mg/kg) surpassed the trigger action value of 65 mg/kg. Total Zn content at 90th percentile in the Pueraria field (197 mg/kg) and maximum value at mine surrounding (76.7 mg/kg) were above the world soil average (70 mg/kg). Pollution load index and EF values indicated severe levels of soil contamination particularly with As and Ti. Hazard index (HI) values for all sites for children (0.7-134.56), adult males (0.05-10.6), and adult females (0.13-12.77) were above 1 and indicated high human health risk especially on children and women. Translocation factor shows that native plant species such as Chromolaena odorata and fern accumulated As, Cu, Ti, and Zn into their shoots and may thus have the potential to reduce the high soil contamination and its associated human health risk.Ecosystem functioning and related risks could become compromised by climate change and severely affect livestock in different ways. Based on four climate indices (i.e., SPI, SPEI, PDSI and SEDI), livestock determinants and biogeochemical proxies, we analysed the temporal and geographical extent of terrestrial ecosystem shift probabilities and drought-wetness risk severity at multiple scales (i.e., land cover, climate and elevation) in the greater Mekong subregion (GMS) during the period 1981-2020 by using different cartographic techniques. The results indicated that in the GMS area, approximately 3.8% experienced the highest ecosystem shift probability, 4% was exposed to a high risk of drought and wetness, and only approximately 55% experienced a low risk of drought and/or wetness stress. Cambodia and Thailand experienced the highest ecosystem shift probability ratio and drought-wetness risk severity compared to other GMS countries. Woody savanna and urban land covers; temperate-fully humid-cold summer and tropical rainfall fully humid climate zones; and elevations -47-200 m and ≥2500 m showed common characteristics leading to a very high ecosystem shift probability and experienced high drought-wetness risk severity.