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In paddy rice farming systems, the degradation of insecticides from the soil reduces their occurrence as well as their levels in surface and groundwater. Degradation of insecticide fenobucarb in the paddy soil-water system was carried out by surface soil collected from paddy rice in the Hue province of Vietnam. Experiments were conducted using a batch technique, the fenobucarb-spiked paddy soils were shaken end-over-end with solutions of pH 7, pH 9, 25 mg L−1 DOC, and 1 critical micelle (cmc) sodium dodecyl sulfate (SDS). After each period (24, 48, 72, ... 144 hours), the soil solutions were separated into the aliquot and the solid phase to analyze fenobucarb and intermediate metabolic products 2-sec-butyl phenol. The decrease of fenobucarb and the appearance of (2-sec-butyl-phenol) were the result of hydrolysis and biodegradation by fenobucarb-acclimatized microorganisms that were capable of degrading fenobucarb in the paddy soil. The degradation of fenobucarb in both the soil and water phases in the paddy soil-water system was enhanced in the experiment with pH 7, followed by those with pH 9, 25 mg L−1 DOC, and 1 cmc SDS. With pH 9, in addition to decomposition by bacteria present in the soil, fenobucarb was hydrolyzed under basic conditions. The presence of 25 mg L−1 DOC and 1 cmc SDS in the aqueous solution increased desorption and microbial activity in the soil and increased the biodegradation efficiency of fenobucarb in the paddy soil-water system. However, the degradation of fenobucarb in the 1 cmc SDS solution was inhibited because SDS solution may be preferentially utilized by microorganisms, and fenobucarb would have a competitive effect with SDS. Irrigation water for paddy fields often receives untreated domestic and industrial wastewater that may contain multiple compounds such as DOC and SDS. Therefore, it contributes to the elimination of fenobucarb insecticide in the paddy soil-water system. [ABSTRACT FROM AUTHOR]

Formalin-fixed paraffin-embedded (FFPE) tissues represent the biggest source of archival materials for molecular biology research and pathology investigations. Nevertheless, fixation by formalin may cause denaturation and modification of macromolecules constraining DNA quality and its downstream applications. In this study, we developed a fast, simple, and cost-effective phenol/chloroform-based protocol for the extraction of high-quality DNA from 101 FFPE colorectal cancer tissue blocks that can be used in multiple molecular studies. DNA samples extracted using this phenol/chloroform protocol and the QIAamp DNA FFPE Tissue kit were evaluated for the quantity, quality, and amplificability. Spectrophotometer analyses revealed significantly higher quality and quantity of DNA samples obtained with the phenol/chloroform protocol as compared to those of the QIAamp DNA FFPE Tissue kit. In addition, the amplificability of these samples as assessed by conventional and multiplex polymerase chain reaction (PCR), followed by sequencing and fragment analyses presented an absolute success rate. Additionally, it is able to amplify a DNA fragment of 725 base-pairs at an adequate amount for downstream applications. This fast, simple, and cost-effective method may facilitate the molecular analyses of a large number of FFPE specimens that best suits the needs of the overall study design in terms of the quality and quantity of the extracted DNA. [ABSTRACT FROM AUTHOR]

For many years, the sculpin has been utilized as a sentinel monitoring species for anthropogenic impacts on the marine environment. To further develop its potential as a screening model body burden of several trace elements, including cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb) and selenium (Se), were investigated. In addition, histopathology in shorthorn sculpins (Myoxocephalus scorpius; n = 20) and fourhorn sculpins (Myoxocephalus quadricornis; n = 10) were examined at three sites around the Scoresby Sound settlement in Central East Greenland. Fourhorn sculpins caught at the most distant site from the settlement, contained significantly higher hepatic Cu and Cd concentrations as well as significantly elevated gill Pb levels compared to the shorthorn sculpins collected at two other sites closer to the settlement. Histological examinations showed that fish with significantly higher concentrations of hepatic Cd and Se exhibited greater nuclear alterations, interstitial hyperplasia/hypertrophy, interstitial mononuclear infiltrations and granulomas. Further, fish with higher Cd and Cu gill tissue levels displayed a significantly higher number of cytoplasmic alterations and lamellar epithelium lifting, hypertrophic and hyperplastic epithelium along with mucus cell hyperplasia. While the presence of liver lesions were not species or sex-specific, the presence of gill lesions decreased in the order female fourhorn sculpins > female shorthorn sculpins > male fourhorn sculpins > male shorthorn sculpins. Hepatic Hg concentrations exceeded known lowest observable effect doses (LOED) for fish (0.1–0.5 μg g−1 ww) in 27% of fish, while liver Cd residues in 80% exceeded LOED (0.42–1.8 μg g−1 ww). Based upon these results, data suggest that using the sculpin as a valuable sentinel fish species histopathology may serve as a reliable tool for assessing marine ecosystem exposure to trace metals. However, confounding physiological and ecological factors also need to be considered. [ABSTRACT FROM AUTHOR]

There is inadequate morphological nomenclature and definition of organ pathology when using wild fish in biomonitoring of environmental pollution. The aim of this investigation was to provide a guide that assesses histology of Shorthorn (Myoxocephalus scorpius) and Fourhorn (Myoxocephalus quadricornis) sculpins obtained from a study using these two fish species as bioindicator organisms to evaluate environmental impact attributed to a dumpsite located in East Greenland. Specific histopathological lesions were quantified on the basis of Bernet et al. and all lesions were photomicrographed, evaluated, and placed into specific categories of five reaction patterns. These were circulatory disturbances, regressive changes, progressive alterations, inflammation, and tumors based on anatomical location, type, and severity. This method is postulated to enable an objective assessment of the histological integrity of fish gills and liver; thus, making it possible to compare sculpin pathology and reaction patterns at different locations. Data suggest that this updated histological guide might be used for identification and quantification of histological lesions when applying sculpins in biomonitoring programs in Greenland and other Arctic regions. [ABSTRACT FROM AUTHOR]

Presents information on mathematics, examining chaotic systems. Overview and analysis of chaotic systems; Examination of varying definitions of chaotic systems; Characteristics of chaotic systems; Statistical data analysis.