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1.

The risk of cancer due to PCB exposure in humans is highly debated. In eastern Slovakia, high exposure of the population to organochlorines (especially PCBs) was associated with various disease and disorder pathways, viz., endocrine disruption, metabolic disorder & diabetes, and cancer, thereby disturbing several cellular processes, including protein synthesis, stress response, and apoptosis. We have evaluated a Slovak cohort (45-month children, at lower and higher levels of PCB exposure from the environment) for disease and disorder development to develop early disease cancer biomarkers that could shed new light on possible mechanisms for the genesis of cancers under such chemical exposures, and identify potential avenues for prevention.

Microarray studies of global gene expression were conducted from the 45-month-old children on the Affymetrix platform followed by Ingenuity Pathway Analysis (IPA®) to associate the affected genes with their mechanistic pathways. High-throughput qRT-PCR TaqMan low-density array (TLDA) was performed to further validate the selected genes on the whole blood cells of the most highly exposed children from the study cohort (n = 71).

TP53, MYC, BCL2, and LRP12 differential gene expressions suggested strong relationships between potential future tumor promotion and PCB exposure in Slovak children. The IPA analysis further detected the most important signaling pathways, including molecular mechanism of cancers, prostate cancer signaling, ovarian cancer signaling, P53 signaling, oncostatin M signaling, and their respective functions (viz., prostate cancer, breast cancer, progression of tumor, growth of tumor, and non-Hodgkin’s disease). The results suggest that PCB exposures, even at the early age of these children, may have lifelong consequences for the future development of chronic diseases.

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Abstract

The main objective of this study is the degradation of a synthetic solution of atrazine by a modified vermiculite catalyzed ozonation, in a rotating packed bed (RPB) reactor. A 0.5?L RPB reactor was used to perform the experiments, using a Central Composite Design (CCD) response surface to construct the quadratic model based on the factors: pH, catalyst concentration and reactor rotation frequency. The response variable was the removal of the organic load measured in terms of Chemical Oxygen Demand (COD). After the complete quadratic model was constructed through the response surface, the COD degradation process had an optimal removal of 41% under the following conditions: pH 8.0, rotation of 1150?rpm and catalyst concentration 0.66?g L?1.  相似文献   
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In Brazil, specifically in the Doce River basin, there is still a great lack of studies on temporal and spatial trends in water quality, since the water quality in the monitoring campaigns is basically evaluated when it comes down to the concentrations of monitored variables. In this sense, the objective of this work was to perform a temporal and spatial trend analysis of water quality data in the Minas Gerais portion of the Doce River basin, Brazil. For this, the Mann–Kendall, seasonal Mann–Kendall and Spearman correlation tests were used in the temporal analysis and the cluster analysis in the spatial analysis. In the analysis of temporal trends, the analyses were performed using the values of the National Sanitation Foundation Water Quality Index (NSFWQI) and the variables that compose it. In the analysis of spatial trends, the stations were evaluated only based on the WQI. With the results of the analysis of temporal trend, it was identified that most stations did not present a statistically significant trend for the WQI. In the stations that presented trends of quality reduction, most of them are in densely populated areas, demonstrating the strong influence of the poor sanitary conditions of the municipalities to the water quality of the basin. When analyzing the variables that compose the WQI, the results found for nitrate demonstrated that water quality deterioration is also affected by the diffuse pollution originating from farming areas. The results for Escherichia coli reinforced the impact of the discharge of domestic effluents and demonstrated the absence of a significative trend is still of concern because it can represent the maintenance of a degradation state in the water bodies. In the spatial trend analysis, the CA grouped the monitoring stations into six clusters based on their similarity among the WQI values, and, together with the results of the other analyses, it was verified that the Caratinga River basin (UGRH5 Caratinga) presented the highest degree of pollution. It was also possible to identify five stations that can be reallocated or deactivated since they have similarities with other stations located in the same watercourse.

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Felton  Adam  Löfroth  Therese  Angelstam  Per  Gustafsson  Lena  Hjältén  Joakim  Felton  Annika M.  Simonsson  Per  Dahlberg  Anders  Lindbladh  Matts  Svensson  Johan  Nilsson  Urban  Lodin  Isak  Hedwall  P. O.  Sténs  Anna  Lämås  Tomas  Brunet  Jörg  Kalén  Christer  Kriström  Bengt  Gemmel  Pelle  Ranius  Thomas 《Ambio》2020,49(5):1065-1066
Ambio - In the original published article, the sentence “Nevertheless, semi-natural forest remnants continue to be harvested and fragmented (Svensson et al. 2018; Jonsson et al. 2019), and...  相似文献   
7.
Mercury is a trace element that is potentially dangerous due its high toxicity and tendency to bioaccumulate in organisms. Currently, high mercury concentrations are seen in the environment especially due climate changes. Studies regarding mercury bioavailability in the southwestern Atlantic Ocean using tuna and tuna-like species are rare. The aim of the present study was to use tuna and tuna-like species (Thunnus atlanticus, Thunnus albacares, Katsuwonus pelamis, Euthynnus alletteratus, Coryphaena hippurus and Sarda sarda) as indicators of the availability of total mercury (THg) in oceanic food webs of the southwestern Atlantic Ocean. THg concentrations varied significantly among species for both muscle and liver (Kruskal–Wallis test; H5,130 = 52.7; p < 0.05; H5,130 = 50.1; p < 0.05, respectively). The lowest concentrations were found in C. hippurus (0.008 mg kg−1 wet weight in the muscle and 0.003 mg kg−1 wet weight in the liver), and the highest concentrations were reported in the muscle of T. atlanticus (1.3 mg kg−1 wet weight) and in the liver of S. sarda (2.5 mg kg−1 wet weight). The continued monitoring of tuna and tuna-like species is necessary to assist in their conservation since tuna can be sentinels of mercury pollution.  相似文献   
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Environmental Science and Pollution Research - The total cultivated area in Brazil reached to 62 million ha in 2018, with the predominance of genetically modified soybean and corn (36 and 17...  相似文献   
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This article examines the conditions under which environmental beat journalists can gain credibility as expert informants. It shows that media storms foster a particular dynamic that can add to this credibility. Comparing a media storm over shale gas development in Quebec with regular coverage of the same issue in British Columbia, this article shows that the coverage space given to environmental beat journalists during a media storm can render their alliance with protest groups mutually beneficial. Beat journalists can benefit from the willingness of these groups to participate in their stories, while the groups benefit from increased visibility. Beat journalists also benefit by being perceived as expert informants in policy networks, a role that they use to encourage policy-makers to take the concerns of protest groups seriously. This dynamic also increases the negativity of the news coverage. The article makes a contribution to knowledge on the role of environmental journalists in policy-making processes.  相似文献   
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