The U.S. EPA Technical Protocol for Evaluating Natural Attenuation of Chlorinated Solvents in Groundwater emphasizes biological reductive dechlorination as the primary mechanism for destruction of chlorinated solvents. However, biological reductive dechlorination could not explain the removal of cis-dichloroethylene (cis-DCE) and 1,1-DCE from a plume of contaminated groundwater in Minnesota. Several recent laboratory studies have demonstrated that common iron minerals such as magnetite can also transform chlorinated alkenes. Laboratory microcosms were constructed with sediment from three depth intervals in the aquifer near the source of the plume. The microcosms were autoclaved to prevent biological transformations. In these autoclaved sediments, the rates of removal of cis-DCE in samples from the shallow, intermediate, and deeper depth intervals in the aquifer were 0.58 +/- 0.09, 2.29 +/- 0.26, and 0.31 +/- 0.08 per year at 95% confidence. The rate of removal of 1,1-DCE in sediment from the shallow interval was 1.37 +/- 0.50 per year. The rates of removal in the microcosms are similar to the rates of attenuation observed in the field. Magnetite was identified in the sediment by X-ray diffraction and optical microscopy. Published rates of transformation of cis-DCE by magnetite are consistent with the rates of removal in the microcosm study.
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http://dx.doi.org/10.1021/es0305609 | DOI Listing |
PLoS One
January 2025
Faculty of Health Sciences, Department of Nursing Sciences, University of Pretoria, Pretoria, South Africa.
The reliability of cardiotocographs as diagnostic tools for fetal well-being is hampered by interpretational variations among healthcare professionals, contributing to high rates of cesarean sections and instrumental deliveries. While adjunct technologies may be used to confirm cases of fetal distress, those in resource constrained areas continue to rely on visual cardiotocograph interpretation to come up with the diagnosis of fetal hypoxia. This study investigated the factors contributing to variations in the visual interpretation of intrapartum cardiotocograph among healthcare professionals in the absence of adjunctive technologies.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Orthopedic and Trauma Surgery, Lucerne Cantonal Hospital, Lucerne, Switzerland.
Background: Low-profile double plating seems a viable alternative to conventional single plating for fixation of midshaft clavicle fractures. This study aims to compare the two techniques regarding healing, complications, and removal rate.
Methods: This retrospective cohort study included all patients >16 years that underwent plate fixation for midshaft clavicle fractures between 2020 and 2022 at one trauma-center.
PLoS One
January 2025
Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, Illinois, United States of America.
The nature of western lowland gorilla social relationships within and between groups is largely understudied, partly due to the challenges of monitoring associations between individuals who live in neighboring groups. In this study, we examined the social relationships of four western lowland gorilla groups in the Ndoki landscape of northern Republic of Congo. To do so, we compiled all-occurrence social interaction and silverback nearest neighbor social networks from data collected during daily group follows conducted over several years.
View Article and Find Full Text PDFWater Environ Res
January 2025
Zhejiang Key Laboratory of Petrochemical Environmental Pollution Control, Zhejiang Ocean University, Zhoushan, P. R. China.
Ocean oil spills can severely impact ecosystems and disrupt marine biodiversity and habitats. Microbial remediation is an effective method for removing thin oil slick contamination. In this study, the adsorption and degradation of low-concentration oil spills by Chlorella vulgaris LH-1 immobilized in konjac glucomannan (KGM) aerogel were investigated.
View Article and Find Full Text PDFJ Fungi (Basel)
January 2025
Environmental Microbiology Group, Institute of Water Research, University of Granada, 18003 Granada, Spain.
A significant concentration of pharmaceuticals has been detected within composted sewage sludge. Their uncomplete removal and lack of monitoring during composting neglects their potentially toxic effects when used as a soil organic amendment. Previously, we successfully implemented a bioaugmentation-composting system focused on toxicity and pharmaceuticals' concentration reduction.
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