Mononuclear chromium(I) alkyne complex (i-Pr2Ph)2nacnacCr(η(2)-C2(SiMe3)2) (1) reacts rapidly with dioxygen to yield chromium(V) dioxo species (i-Pr2Ph)2nacnacCr(O)2 (2). The mechanism of this oxygen cleavage has been studied experimentally and computationally. Isotope labeling studies rule out a direct four-electron oxidative addition of O2 to one chromium atom, which involves a spin-forbidden transformation. Instead, the reaction likely proceeds via an unsymmetric binuclear chromium bis(μ-oxo) complex. The latter has been independently prepared and structurally characterized. Its reactivity with O2 is consistent with the proposed mechanism.
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http://dx.doi.org/10.1021/ja408357x | DOI Listing |
Acta Bioeng Biomech
June 2024
1Institute of Applied Sciences, Academy of Physical Education, Kraków, Poland.
: The aim of this study was to investigate the effect of substrate - polycaprolactone (PCL)-based porous membrane modified with rosmarinic acid (RA), (PCL-RA) and to determine the optimal values of low field laser irradiation (LLLT) as stimulators of biological response of RAW 264.7 macrophages. : The porous polymer membrane was obtained by the phase inversion method, the addition of rosmarinic acid was 1%wt.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Earth and Environmental Sciences, University of Illinois at Chicago, Chicago, IL, United States of America.
Municipal solid waste (MSW) landfills represent underexplored microbial ecosystems. Landfills contain variable amounts of antibiotic and construction and demolition (C&D) wastes, which have the potential to alter microbial metabolism due to biocidal or redox active components, and these effects are largely underexplored. To circumvent the challenge of MSW heterogeneity, we conducted a 65-day time series study on simulated MSW microcosms to assess microbiome changes using 16S rRNA sequencing in response to 1) Fe(OH)3 and 2) Na2SO4 to represent redox active components of C&D waste as well as 3) antibiotics.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
February 2025
Center for Medical Research and Innovation, Shanghai Pudong Hospital, Institutes of Biomedical Sciences, Chinese Academy of Medical Sciences (RU069), Medical College of Fudan University, Shanghai 201399, China.
Ten-eleven translocation (TET) enzymes oxidize 5-methylcytosine (mC) in DNA, contributing to the regulation of gene transcription. Diverse mutations of TET2 are frequently found in various blood cancers, yet the full scope of their functional consequences has been unexplored. Here, we report that a subset of TET2 mutations identified in leukemia patients alter the substrate specificity of TET2 from acting on mC to thymine.
View Article and Find Full Text PDFEnviron Toxicol Chem
January 2025
Aquatic Toxicology Laboratory, St Cloud State University, Minnesota, USA.
Treated municipal wastewater effluent is an important pathway for Contaminants of Emerging Concern (CEC) to enter aquatic ecosystems. As the aging wastewater infrastructure in many industrialized countries requires upgrades or replacement, assessing new treatment technologies in the context of CEC effects may provide additional support for science-based resource management. Here, we used three lines of evidence, analytical chemistry, fish exposure experiments, and fish and water microbiome analysis, to assess the effectiveness of membrane bioreactor treatment (MBR) to replace traditional activated sludge treatment.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, 208016, India.
The atmospheric dicarboxylic acids (DCAs) have a significant impact on the climate and indirectly affect human health, making them important organic substances. PM bound DCAs were analysed for Jorhat, India, 2019. In addition to the temporal variability, seasonal variation throughout the year and the impact of varying meteorological factors on DCAs concentration have also been studied.
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