9,618 results match your criteria atmospheric oxygen

Metagenomics and Quantitative Stable Isotope Probing Offer Insights into Metabolism of Polycyclic Aromatic Hydrocarbon Degraders in Chronically Polluted Seawater.

mSystems 2021 May 11;6(3). Epub 2021 May 11.

Department of Biological Sciences, University of Southern California, Los Angeles, California, USA

Bacterial biodegradation is a significant contributor to remineralization of polycyclic aromatic hydrocarbons (PAHs)-toxic and recalcitrant components of crude oil as well as by-products of partial combustion chronically introduced into seawater via atmospheric deposition. The Deepwater Horizon oil spill demonstrated the speed at which a seed PAH-degrading community maintained by chronic inputs responds to acute pollution. We investigated the diversity and functional potential of a similar seed community in the chronically polluted Port of Los Angeles (POLA), using stable isotope probing with naphthalene, deep-sequenced metagenomes, and carbon incorporation rate measurements at the port and in two sites in the San Pedro Channel. Read More

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Photodegradation of α-Pinene Secondary Organic Aerosol Dominated by Moderately Oxidized Molecules.

Environ Sci Technol 2021 May 7. Epub 2021 May 7.

Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland.

Atmospheric secondary organic aerosol (SOA) undergoes chemical and physical changes when exposed to UV radiation, affecting the atmospheric lifetime of the involved molecules. However, these photolytic processes remain poorly constrained. Here, we present a study aimed at characterizing, at a molecular level and in real time, the chemical composition of α-pinene SOA exposed to UV-A light at 50% relative humidity in an atmospheric simulation chamber. Read More

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Isotopic evidence for acidity-driven enhancement of sulfate formation after SO emission control.

Sci Adv 2021 May 5;7(19). Epub 2021 May 5.

Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Yokohama 226-8502, Japan.

After the 1980s, atmospheric sulfate reduction is slower than the dramatic reductions in sulfur dioxide (SO) emissions. However, a lack of observational evidence has hindered the identification of causal feedback mechanisms. Here, we report an increase in the oxygen isotopic composition of sulfate ([Formula: see text]) in a Greenland ice core, implying an enhanced role of acidity-dependent in-cloud oxidation by ozone (up to 17 to 27%) in sulfate production since the 1960s. Read More

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Reactive capture using metal looping: the effect of oxygen.

Faraday Discuss 2021 May 4. Epub 2021 May 4.

UK Centre for Carbon Dioxide Utilization, Department of Chemical and Biological Engineering, University of Sheffield, Sir Robert Hadfield Building, Sheffield, UK.

In the effort to create a sustainable future economy, the ability to directly convert dilute gas-phase CO2 in waste gas streams into useful products would be a valuable tool, which may be achievable using Grignard reagents as both the capture and the conversion materials. The magnesium salt by-product can be recovered, and metallic magnesium regenerated through conventional high-efficiency electrolysis. This stoichiometric approach is known as metal looping, where the magnesium acts as the energy vector for the capture and conversion, allowing both to occur at room temperature and atmospheric pressure. Read More

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Plasma tailored reactive nitrogen species in MOF derived carbon materials for hybrid sodium-air batteries.

Dalton Trans 2021 May 4. Epub 2021 May 4.

Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China and State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China.

The rational design of efficient and durable electrocatalysts to accelerate sluggish oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) kinetics is highly desirable for enhancing the efficiency of fuel cells and metal-air batteries. Here, we demonstrated a low-temperature plasma strategy at atmospheric pressure for enhancing the catalytic activity of metal-organic framework derived N-doped carbon nanotubes (MOF-NCNTs) by changing the relative contents of Co-Nx sites, Co-Co bonds and pyridinic-N. The increase of pyridinic-N/pyrrolic-N ratio improves the ORR performance, while unsaturated Co-Nx sites and strong Co-Co bonds promote the OER performance. Read More

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Groundwater pollution assessment in a coastal aquifer in Cape Coast, Ghana.

Heliyon 2021 Apr 17;7(4):e06751. Epub 2021 Apr 17.

Environmental Science Department, University of Cape Coast, Ghana.

This work presents an assessment of the chemico-physical and microbial quality of water samples from hand-dug wells in the shallow aquifer of three communities neighbouring the University of Cape Coast, Ghana. Sanitary risk inspection was undertaken at each well location and the physical parameters including electrical conductivity, pH, Dissolved Oxygen (DO) and etc. were measured in situ via probes. Read More

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Transition Metal Salts of Carboxylated Multiwalled Carbon Nanotubes in Combination with -hydroxyphthalimide as Catalytic Systems for Hydrocarbon Oxidation.

Materials (Basel) 2021 Apr 29;14(9). Epub 2021 Apr 29.

Department of Organic Chemical Technology and Petrochemistry, Silesian University of Technology, B. Krzywoustego 4, 44-100 Gliwice, Poland.

In this study, the transition metal (Co (II), Cu (II), and Mn (II)) salts of carboxylated carbon nanotubes were synthesized and characterized (the determined metal contents were in the range of 0.89-1.16%). Read More

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Recent Advances in the Plasma-Assisted Synthesis of Zinc Oxide Nanoparticles.

Nanomaterials (Basel) 2021 Apr 30;11(5). Epub 2021 Apr 30.

Department of Textiles, Graphic Arts and Design, Faculty of Natural Sciences and Engineering, University of Ljubljana, Aškerčeva 12, 1000 Ljubljana, Slovenia.

An overview of recent work on the low-temperature plasma-assisted synthesis of zinc oxide (ZnO) nanoparticles is presented and interpreted in terms of gas-phase and surface reactions with illustrated examples. The thermodynamical nonequilibrium conditions allow the formation of chemically reactive species with a potential energy of several eV, which readily interact with the Zn precursors and initiate reactions leading to the formation of nanoparticles or nanowires. The high-quality nanowires were synthesized from Zn powders only upon interaction with moderately ionized plasma in a narrow range of plasma parameters. Read More

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Chlorine disinfection facilitates natural transformation through ROS-mediated oxidative stress.

ISME J 2021 May 3. Epub 2021 May 3.

Advanced Water Management Centre (AWMC), The University of Queensland, St Lucia, Brisbane, QLD, Australia.

The bacterial infection that involves antimicrobial resistance is a rising global threat to public health. Chlorine-based water disinfection processes can inactivate antibiotic resistant bacteria. However, at the same time, these processes may cause the release of antibiotic resistance genes into the water as free DNA, and consequently increase the risk to disseminate antibiotic resistance via natural transformation. Read More

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Comparison of picoeukaryote community structures and their environmental relationships between summer and autumn in the southern Chukchi Sea.

Extremophiles 2021 May 3;25(3):235-248. Epub 2021 May 3.

Key Laboratory of Global Change and Marine-Atmospheric Chemistry, Third Institute of Oceanography, MNR, Xiamen, 361005, China.

Picoeukaryotes constitute an important component of the living biomass of oceanic communities and play major roles in biogeochemical cycles. There are very few studies on picoeukaryotes found in the Chukchi Sea. This work shows the relationship between community distribution and composition of picoeukaryotes residing in water masses and physicochemical factors in the southern Chukchi Sea studied in both midsummer (July) and early autumn (September), 2012. Read More

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The stable isotope composition of hoarfrost.

Isotopes Environ Health Stud 2021 May 3:1-14. Epub 2021 May 3.

Emil Racoviță Institute of Speleology, Cluj-Napoca, Romania.

Atmospherically deposited hoarfrost is probably the least important quantitative component of the hydrosphere, yet in places acts as an important source of water. Although countless studies have investigated the stable isotope composition of virtually all other components of the global hydrosphere, little is known on its stable isotope composition. We addressed this gap in knowledge by investigating the stable isotope composition of hoarfrost and precipitation in the Southern Carpathian Mountains (East-Central Europe) in relation with the local and regional meteorological parameters and hoarfrost characteristics. Read More

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Effects of reactive oxygen species generation induced by Wonju City particulate matter on mitochondrial dysfunction in human middle ear cell.

Environ Sci Pollut Res Int 2021 May 1. Epub 2021 May 1.

Department of Environmental Engineering, College of Public Health, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do, 26493, South Korea.

Atmospheric particulate matter (PM) contains different components that can elicit varying adverse health effects in humans and animals. Studies on PM toxicity and its underlying mechanisms in the middle ear are limited, and they generally use a PM standard. However, as PM composition varies temporally and geographically, it is crucial to identify the toxic PM constituents according to season and region and investigate their associated health effects. Read More

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Chemisorbed Superoxide Species Enhanced the High Catalytic Performance of Ag/CoO Nanocubes for Soot Oxidation.

ACS Appl Mater Interfaces 2021 May 30;13(18):21436-21449. Epub 2021 Apr 30.

School of Environment and Energy, South China University of Technology, Guangzhou 510640, China.

The respective action mode between surface-adsorbed oxygen and bulk lattice oxygen during catalytic soot oxidation is still not fully recognized. Herein, a series of Ag-loaded CoO catalysts with different Ag loading amounts were prepared by the impregnation method, and 5% Ag/CoO presented competitive catalytic activity toward soot combustion with a below 290 °C in 10% O/N. This remarkable improvement in catalytic performance could be primarily attributed to the enhanced Ag-CoO metal-support interaction induced by the formation of uniform, dispersive, and suitable size metallic Ag nanoparticles. Read More

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Enhancing Hydrodeoxygenation of Bio-oil via Bimetallic Ni-V Catalysts Modified by Cross-Surface Migrated-Carbon from Biochar.

ACS Appl Mater Interfaces 2021 May 30;13(18):21482-21498. Epub 2021 Apr 30.

College of Materials and Energy, South China Agricultural University, Guangzhou 510640, China.

Aromatics from selective hydrodeoxygenation (HDO) of biomass-derived bio-oil are an ideal feedstock for replacing industrial fossil products. In this study, biochar-modified Hβ/Ni-V catalysts were prepared and tested in the atmospheric HDO of guaiacol and bio-oil to produce aromatics. Compared with unmodified Hβ/Ni-V, higher HDO activity was achieved in catalysts with all kinds of biochar modifications. Read More

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Surface modification of PMMA polymer and its composites with PCBM fullerene derivative using an atmospheric pressure microwave argon plasma sheet.

Sci Rep 2021 Apr 29;11(1):9270. Epub 2021 Apr 29.

Institute of Fluid Flow Machinery, Polish Academy of Sciences, Fiszera 14, 80-231, Gdańsk, Poland.

This paper presents the results of experimental investigations of the plasma surface modification of a poly(methyl methacrylate) (PMMA) polymer and PMMA composites with a [6,6]-phenyl-C61-butyric acid methyl ester fullerene derivative (PCBM). An atmospheric pressure microwave (2.45 GHz) argon plasma sheet was used. Read More

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Direct and Indirect Bactericidal Effects of Cold Atmospheric-Pressure Microplasma and Plasma Jet.

Molecules 2021 Apr 26;26(9). Epub 2021 Apr 26.

Graduate School of Science and Technology, Shizuoka University, Hamamatsu 832-8561, Japan.

The direct and indirect bactericidal effects of dielectric barrier discharge (DBD) cold atmospheric-pressure microplasma in an air and plasma jet generated in an argon-oxygen gas mixture was investigated on and . An AC power supply was used to generate plasma at relatively low discharge voltages (0.9-2. Read More

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Can Alveolar-Arterial Difference and Lung Ultrasound Help the Clinical Decision Making in Patients with COVID-19?

Diagnostics (Basel) 2021 Apr 23;11(5). Epub 2021 Apr 23.

Emergency Medicine Unit and Emergency Medicine Postgraduate Training Program, Department of Internal Medicine, University of Pavia, IRCCS Policlinico San Matteo Foundation, 27100 Pavia, Italy.

Background: COVID-19 is an emerging infectious disease, that is heavily challenging health systems worldwide. Admission Arterial Blood Gas (ABG) and Lung Ultrasound (LUS) can be of great help in clinical decision making, especially during the current pandemic and the consequent overcrowding of the Emergency Department (ED). The aim of the study was to demonstrate the capability of alveolar-to-arterial oxygen difference (AaDO) in predicting the need for subsequent oxygen support and survival in patients with COVID-19 infection, especially in the presence of baseline normal PaO/FiO ratio (P/F) values. Read More

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Plasma Treated Water Solutions in Cancer Treatments: The Contrasting Role of RNS.

Antioxidants (Basel) 2021 Apr 14;10(4). Epub 2021 Apr 14.

CNR- Istituto di Nanotecnologia (CNR-NANOTEC) UoS Bari, c/o Dipartimento di Chimica, Università degli Studi di Bari Aldo Moro, via Orabona, 4, 70126 Bari, Italy.

Plasma Treated Water Solutions (PTWS) recently emerged as a novel tool for the generation of Reactive Oxygen and Nitrogen Species (ROS and RNS) in liquids. The presence of ROS with a strong oxidative power, like hydrogen peroxide (HO), has been proposed as the main effector for the cancer-killing properties of PTWS. A protective role has been postulated for RNS, with nitric oxide (NO) being involved in the activation of antioxidant responses and cell survival. Read More

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Cold Atmospheric Plasma Increases Temozolomide Sensitivity of Three-Dimensional Glioblastoma Spheroids via Oxidative Stress-Mediated DNA Damage.

Cancers (Basel) 2021 Apr 8;13(8). Epub 2021 Apr 8.

Research Group PLASMANT, Department of Chemistry, University of Antwerp, 2610 Antwerp, Belgium.

Glioblastoma multiforme (GBM) is the most frequent and aggressive primary malignant brain tumor in adults. Current standard radiotherapy and adjuvant chemotherapy with the alkylating agent temozolomide (TMZ) yield poor clinical outcome. This is due to the stem-like properties of tumor cells and genetic abnormalities in GBM, which contribute to resistance to TMZ and progression. Read More

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The Influence of Cold Atmospheric Pressure Plasma-Treated Media on the Cell Viability, Motility, and Induction of Apoptosis in Human Non-Metastatic (MCF7) and Metastatic (MDA-MB-231) Breast Cancer Cell Lines.

Int J Mol Sci 2021 Apr 8;22(8). Epub 2021 Apr 8.

Department of Analytical Chemistry and Chemical Metallurgy, Faculty of Chemistry, Wroclaw University of Science and Technology, Wybrzeze St. Wyspianskiego 27, 50-370 Wroclaw, Poland.

Breast cancer remains the most common type of cancer, occurring in middle-aged women, and often leads to patients' death. In this work, we applied a cold atmospheric pressure plasma (CAPP)-based reaction-discharge system, one that is unique in its class, for the production of CAPP-activated media (DMEM and Opti-MEM); it is intended for further uses in breast cancer treatment. To reach this aim, different volumes of DMEM or Opti-MEM were treated by CAPP. Read More

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Argon Plasma Exposure Augments Costimulatory Ligands and Cytokine Release in Human Monocyte-Derived Dendritic Cells.

Int J Mol Sci 2021 Apr 6;22(7). Epub 2021 Apr 6.

The Centre for Innovation Competence (ZIK) Plasmatis, Leibniz Institute for Plasma Science and Technology (INP), 17489 Greifswald, Germany.

Cold physical plasma is a partially ionized gas expelling many reactive oxygen and nitrogen species (ROS/RNS). Several plasma devices have been licensed for medical use in dermatology, and recent experimental studies suggest their putative role in cancer treatment. In cancer therapies with an immunological dimension, successful antigen presentation and inflammation modulation is a key hallmark to elicit antitumor immunity. Read More

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Efficient Photooxidation of Methane to Liquid Oxygenates over ZnO Nanosheets at Atmospheric Pressure and Near Room Temperature.

Nano Lett 2021 May 29;21(9):4122-4128. Epub 2021 Apr 29.

Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei 230026, P. R. China.

Direct CH photoconversion into liquid oxygenates under mild conditions still represents a huge challenge. Herein, two-dimensional oxide semiconductors are designed to generate abundant active O species for activating C-H bond of methane. Taking the synthetic ZnO nanosheets as an example, in situ electron paramagnetic resonance spectra verified their lattice oxygen atoms could capture photoexcited holes and generate active O species, which could efficiently abstract H from CH to generate ·CH radicals. Read More

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Fine particles in surgical smoke affect embryonic cardiomyocyte differentiation through oxidative stress and mitophagy.

Ecotoxicol Environ Saf 2021 Jul 25;217:112259. Epub 2021 Apr 25.

The Ninth People's Hospital of Shanghai, Jiao Tong University School of Medicine, Shanghai 200011, PR China. Electronic address:

Surgical smoke is widespread in operating rooms, and fine particles are the main toxic components. However, the effect of fine particles in surgical smoke on embryonic development has not yet been studied. This study evaluated the effect of fine particles in surgical smoke on embryonic development and compared it with that of atmospheric fine particles. Read More

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Declining Oxygen Level as an Emerging Concern to Global Cities.

Environ Sci Technol 2021 Apr 27. Epub 2021 Apr 27.

Enlightening Bioscience Research Center, Mississauga L4X 2X7, Canada.

Rising CO concentration and temperatures in urban areas are now well-known, but the potential of an emerging oxygen crisis in the world's large cities has so far attracted little attention from the science community. Here, we investigated the oxygen balance and its related risks in 391 global large cities (with a population of more than 1 million people) using the oxygen index (O), which is the ratio of oxygen consumption to oxygen production. Our results show that the global urban areas, occupying only 3. Read More

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Therapeutic effect of cold atmospheric plasma and its combination with radiation as a novel approach on inhibiting cervical cancer cell growth (HeLa cells).

Bioorg Chem 2021 Apr 7;111:104892. Epub 2021 Apr 7.

Cancer Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran. Electronic address:

Cervical cancer is one of the important cancers in women. Research on novel treatment approach can reduce the mortality and burden. Although radiotherapy is a common treatment, its negative side effects have concerned physician. Read More

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Enteric Viruses and Pepper Mild Mottle Virus Show Significant Correlation in Select Mid-Atlantic Agricultural Waters.

Appl Environ Microbiol 2021 Apr 23. Epub 2021 Apr 23.

University of Delaware, Department of Animal and Food Sciences, Newark, DE, United States

Enteric viruses (EV) are the largest contributors to foodborne illness and outbreaks globally. Their ability to persist in the environment, coupled with the challenges experienced in environmental monitoring create a critical aperture through which agricultural crops may become contaminated. This study involved a seventeen-month investigation of select human enteric viruses and viral indicators in non-traditional irrigation water sources, surface and reclaimed waters, in the Mid-Atlantic region of the United States. Read More

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Sensitivities of Ozone Air Pollution in the Beijing-Tianjin-Hebei Area to Local and Upwind Precursor Emissions Using Adjoint Modeling.

Environ Sci Technol 2021 05 23;55(9):5752-5762. Epub 2021 Apr 23.

Department of Mechanical Engineering, University of Colorado Boulder, Boulder, Colorado 80309, United States.

Effective mitigation of surface ozone pollution entails detailed knowledge of the contributing precursors' sources. We use the GEOS-Chem adjoint model to analyze the precursors contributing to surface ozone in the Beijing-Tianjin-Hebei area (BTH) of China on days of different ozone pollution severities in June 2019. We find that BTH ozone on heavily polluted days is sensitive to local emissions, as well as to precursors emitted from the provinces south of BTH (Shandong, Henan, and Jiangsu, collectively the SHJ area). Read More

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Plant biology for space exploration - Building on the past, preparing for the future.

Life Sci Space Res (Amst) 2021 May 19;29:1-7. Epub 2021 Jan 19.

Biology Department, University of Louisiana at Lafayette, Lafayette, LA, 70504-3602, United States. Electronic address:

A review of past insights of space experiments with plants outlines basic space and gravity effects as well as gene expression. Efforts to grow plants in space gradually incorporated basic question on plant productivity, stress response and cultivation. The prospect of extended space missions as well as colonization of the Moon and Mars require better understanding and therefore research efforts on biomass productivity, substrate and water relations, atmospheric composition, pressure and temperature and substrate and volume (growth space) requirements. Read More

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Gas-to-Particle Partitioning of Cyclohexene- and α-Pinene-Derived Highly Oxygenated Dimers Evaluated Using COSMO.

J Phys Chem A 2021 May 22;125(17):3726-3738. Epub 2021 Apr 22.

Nano and Molecular Systems Research Unit, University of Oulu, 90014 Oulu, Finland.

Oxidized organic compounds are expected to contribute to secondary organic aerosol (SOA) if they have sufficiently low volatilities. We estimated saturation vapor pressures and activity coefficients (at infinite dilution in water and a model water-insoluble organic phase) of cyclohexene- and α-pinene-derived accretion products, "dimers", using the COSMO19 program. We found that these two property estimates correlate with the number of hydrogen bond-donating functional groups and oxygen atoms in the compound. Read More

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