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111.
Gestational age determination by traditional tools (last menstrual period, ultrasonography measurements and Ballard Maturational Assessment in newborns) has major limitations and therefore there is a need to find different approaches. In this study, we looked for a molecular marker that can be used to determine the accurate gestational age of the newborn. To this end, we performed reduced representation bisulfite sequencing (RRBS) on 41 cord blood and matching placenta samples from women between 25 and 40 weeks of gestation and generated an epigenetic clock based on the methylation level at different loci in the genome. We identified a set of 332 differentially methylated regions (DMRs) that undergo demethylation in late gestational age in cord blood cells and can predict the gestational age (r = −.7, P = 2E-05). Once the set of 411 DMRs that undergo de novo methylation in late gestational age was used in combination with the first set, it generated a more accurate clock (R = .77, P = 1.87E-05). We have compared gestational age determined by Ballard score assessment with our epigenetic clock and found high concordance. Taken together, this study demonstrates that DNA methylation can accurately predict gestational age and thus may serve as a good clinical predictor.  相似文献   
112.
L. Asplund  E. Jakobsson  P. Haglund     . Bergman 《Chemosphere》1994,28(12):2075-2086
The two isomers 1,2,3,5,6,7- and 1,2,3,4,6,7-hexachloronaphthalene are shown to be selectively retained in the liver of rats orally dosed with the commercial PCN product Halowax 1014. The retention was further studied by dosing rats orally with a mixture of the two compounds. The rats were sacrificed after 1, 10, 35 and 120 days, respectively. The two hexachloronaphthalenes were found to be strongly retained in the liver and the concentration ratios liver/adipose tissue were remarkably high. 1,2,3,5,6,7- And 1,2,3,4,6,7-hexachloronaphthalene were also found to be present in two environmental samples from the Swedish east coast, cod liver and guillemot egg.  相似文献   
113.
We draw from social categorization theory and the actor–observer hypothesis to extend previous research regarding receiving high levels of help from team members. Specifically, we explore how a team member's performance feedback on how they handled a disproportionately heavy share of the team's workload and how their racial distance from the rest of their teammates affect the amount of helping that person receives from their teammates. Results from a laboratory study in which 79 teams worked on a computerized, decision‐making task demonstrated a three‐way interaction between workload, performance feedback, and the racial distance between the feedback recipient and the rest of their teammates. Racially distant negative feedback recipients who had a disproportionately heavy share of their team's workload received less help from teammates than their racially similar counterparts. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
114.
Soil and groundwater contamination by per- and polyfluoroalkyl substances (PFAS) has been a significant concern to human health and environmental quality. Remediation of contaminated sites is crucial to prevent plume expansion but can prove challenging due to the persistent nature of PFAS combined with their high aqueous mobility. In this case study, we investigated the potential of colloidal activated carbon (CAC) for soil stabilization at the pilot scale, aiming to entrap PFAS and prevent their leaching from soil into groundwater. Monitoring of the site revealed the presence of two potential sources of PFAS contamination at concentrations up to 23 μg L−1 for ∑11PFAS in groundwater. After CAC application, initial results indicated a 76% reduction of ∑11PFAS and high removal rates for long-chain PFAS, such as perfluorooctane sulfonic acid and perfluorooctanoic acid. A spike in concentrations was noticed 6 months after injection of CAC, showing a rebound of the plume and a reduction of treatment effectiveness. Based on long-term monitoring data, the treatment effectiveness for ∑11PFAS dropped to 52%. The rebound of concentrations was attributed to the plume bypass of the barrier due to the presence of high conductivity zones, which likely occurred because of seasonal changes in groundwater flow directions or the CAC application at the site. This demonstrates the need for a detailed and accurate hydrogeological understanding of contaminated sites before designing and applying stabilization techniques, especially at sites with high geologic and hydrologic complexity. The results herein can serve as a guideline for treating similar sites and help avoid potential pitfalls of remedial efforts.  相似文献   
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