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Hurricane Harvey caused widespread flooding along the Texas Gulf Coast in August 2017; some areas of Houston received >150 cm of rainfall within a few days. Due to concerns over fecal contamination of floodwaters, surface water samples were collected at six locations in the southeastern Houston area immediately before and after the hurricane and then every 1 to 2 weeks thereafter over a 2-month period. Total E. coli was enumerated using the IDEXX Quanti-Tray/2000 system. DNA extracted from water samples was analyzed via quantitative real-time PCR (qPCR) for general and source-specific total Bacteroidales and human Bacteroidales markers, and digital PCR (dPCR) for antibiotic resistance genes (ARG) and a plasmid (pBI143) associated with human waste. SourceTracker2 was used to determine human source contributions based on metagenomic analysis of PCR-amplified 16S rRNA gene fragments. Samples collected immediately after the hurricane had elevated levels of E. coli, ranging from 488 to 1,733 CFU 100 ml−1. After 1 week, E. coli levels decreased to <100 MPN 100 ml−1. Total Bacteroidales numbers were elevated immediately following the hurricane and remained high for 12 days. Human-source contributions, as assessed by PCR methods and metagenomic analysis, peaked within 12 days after the hurricane consistently across all sampling sites. Multiple regression analysis of environmental parameters, copies of ARG and pBI143, and metagenomic data confirmed that human waste caused the dramatic, short-term, high levels of fecal contamination of floodwaters generated by Hurricane Harvey. Fecal indicators approached normal background levels approximately 3 weeks after the rainfall ended. [ABSTRACT FROM AUTHOR]

Pectinase accelerates hemp retting. An elevated temperature during the enzymatic action is favorable for bacterial colonization. Industrial hemp (Cannabis sativa L.) bast fiber was retted in a 40 °C water bath under four different conditions: water retting, pectinase retting, bacterial retting, and bacterial retting with the presence of pectinase. Bacterial communities were sampled from the retting liquid of each condition at the beginning of retting and on days 1, 3, and 5. The bacterial successions were identified by 16S rRNA gene metagenomic sequencing. The results showed that Bacillaceae dominated the hemp retting conditions containing 1% (m/v) pectinase, suggesting that pectinase can manipulate the bacterial community succession by changing the nutrients available to bacteria through the breakdown of pectin. Micromorphological analysis also observed the degradation of a gum-like substance and the aggregation of bacteria with the addition of pectinase. [ABSTRACT FROM AUTHOR]

Maternal separation with early weaning (MSEW) is a popular early life stress (ELS) model in rodents, which emulates childhood neglect through scheduled mother-offspring separation. Although variations of ELS models, including maternal separation and MSEW, have been published for the mouse species, the reported results are inconsistent. Corticosterone is considered the main stress hormone involved in regulating stress responses in rodents—yet generating a robust and reproducible corticosterone response in mouse models of ELS has been elusive. Considering the current lack of standardization for MSEW protocols, these inconsistent results may be attributed to variations in model methodologies. Here, we compared the effects of select early wean diet sources—which are the non-milk diets used to complete early weaning in MSEW pups—on the immediate stress phenotype of C57BL/6J mice at postnatal day 21. Non-aversive handling was an integral component of our modified MSEW model. The evaluation of body weight and serum corticosterone revealed the early wean diet to be a key variable in the resulting stress phenotype. Interestingly, select non-milk diets facilitated a stress phenotype in which low body weight was accompanied by significant corticosterone elevation. Our data indicate that dietary considerations are critical in MSEW-based studies and provide insight into improving the reproducibility of key stress-associated outcomes as a function of this widely used ELS paradigm. [ABSTRACT FROM AUTHOR]

Ticks are vectors for a variety of microorganisms, many of which are known agents of zoonotic disease. Although much current research is focused on areas where these diseases are common, [...]

Describes the establishment of a hermeneutic circle of portfolio researchers (writing teachers from Alaska to Florida) acting as "outside readers" for each other--six months into the project, the group established an e-mail network called "Portnet." Contemplates the group's experiences during Portnet's first year. (PA)