1,829 results match your criteria atmospheric partial


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

Nano Lett 2021 Apr 29. 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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Characteristics of tailpipe volatile halogenated hydrocarbon (VHC) emissions from in-use vehicles during real-world driving.

Environ Sci Pollut Res Int 2021 Apr 23. Epub 2021 Apr 23.

State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.

Vehicular emissions have become a primary anthropogenic source of urban atmospheric volatile halogenated hydrocarbons (VHCs) with the rapid increase of vehicle population, while characteristics of the VHC emissions from different vehicles were rarely systematically investigated. In this study, the on-road tailpipe emissions were sampled from seven in-use vehicles, including two light-duty gasoline vehicles (LDGV), three light-duty diesel trucks (LDDT), one heavy-duty diesel truck (HDDT), and a liquefied petroleum gas-electric hybrid bus (LPGB), using a portable emission measurement system (PEMS) combined with summa canisters, and 35 individual VHC species were identified by a gas chromatography mass spectrometry detector (GC-MSD). Results showed that VHC emissions under urban driving conditions were much higher than those on the suburban roads and highways. Read More

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Drought-Induced Xylem Embolism Limits the Recovery of Leaf Gas Exchange in Scots Pine.

Plant Physiol 2020 Oct;184(2):852-864

Karlsruhe Institute of Technology, KIT Campus Alpin, Institute of Meteorology and Climate Research- Atmospheric Environmental Research, 82467 Garmisch-Partenkirchen, Germany.

Climate change increases the occurrence of prolonged drought periods with large implications for forest functioning. Scots pine (Pinus sylvestris) is one of the most abundant conifers worldwide, and evidence is rising that its resilience to severe drought is limited. However, we know little about its ability to recover from drought-induced embolism. Read More

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October 2020

The role of the three body photodissociation channel of water in the evolution of dioxygen in astrophysical applications.

Phys Chem Chem Phys 2021 Apr;23(15):9235-9248

Department of Chemistry, University of Colorado, Boulder, CO 80309-215, USA.

A recent experiment at the Dalian Coherent Light Source (DCLS) has provided measurements of the partial cross sections for the photodissociation of water vapor over an unprecedented range of wavelengths in the vacuum ultraviolet (VUV) region. It was found that the three body dissociation channel, H + H + O(3P/1D), becomes prominent at wavelengths shorter than the Lyman α-line at 121.6 nm. Read More

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Highlighting the compound risk of COVID-19 and environmental pollutants using geospatial technology.

Sci Rep 2021 04 16;11(1):8363. Epub 2021 Apr 16.

College of Horticulture and Forestry, Rani Lakshmi Bai Central Agricultural University, Jhansi, 284003, India.

The new COVID-19 coronavirus disease has emerged as a global threat and not just to human health but also the global economy. Due to the pandemic, most countries affected have therefore imposed periods of full or partial lockdowns to restrict community transmission. This has had the welcome but unexpected side effect that existing levels of atmospheric pollutants, particularly in cities, have temporarily declined. Read More

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Phase relations and thermoelasticity of magnesium silicide at high pressure and temperature.

J Chem Phys 2021 Apr;154(14):144701

Department of Materials Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.

Within the exploration of sustainable and functional materials, narrow bandgap magnesium silicide semiconductors have gained growing interest. Intriguingly, squeezing silicides to extreme pressures and exposing them to non-ambient temperatures proves fruitful to study the structural behavior, tune the electronic structure, or discover novel phases. Herein, structural changes and thermoelastic characteristics of magnesium silicides were probed with synchrotron x-ray diffraction techniques using the laser-heated diamond anvil cell and large volume press at high pressure and temperature and temperature-dependent synchrotron powder diffraction. Read More

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Ultrawhite BaSO Paints and Films for Remarkable Daytime Subambient Radiative Cooling.

ACS Appl Mater Interfaces 2021 Apr 15. Epub 2021 Apr 15.

School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, United States.

Radiative cooling is a passive cooling technology that offers great promises to reduce space cooling cost, combat the urban island effect, and alleviate the global warming. To achieve passive daytime radiative cooling, current state-of-the-art solutions often utilize complicated multilayer structures or a reflective metal layer, limiting their applications in many fields. Attempts have been made to achieve passive daytime radiative cooling with single-layer paints, but they often require a thick coating or show partial daytime cooling. Read More

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Why Hydrocephalus Patients Suffer When the Weather Changes: A New Hypothesis.

Acta Neurochir Suppl 2021 ;131:315-317

The Interface Group, Institute of Physiology, University of Zurich, Zurich, Switzerland.

Hydrocephalus patients complain about symptoms related to weather changes, especially changes in atmospheric pressure (p). We aimed to determine which physical, physiological, and pathophysiological effects can explain this phenomenon. We hypothesized that intracranial pressure (ICP) is influenced by changes of intracranial blood volume caused by autoregulatory changes in arterial diameter as a reaction to changing levels of arterial CO partial pressure (paCO) caused by changes in atmospheric pressure (p). Read More

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January 2021

Integrating column leaching experiments and geochemical modelling to predict the long-term alkaline stability during erosion process for gypsum amended bauxite residue.

J Environ Manage 2021 Jul 7;289:112479. Epub 2021 Apr 7.

School of Metallurgy and Environment, Central South University, Changsha, 410083, China. Electronic address:

Gypsum amendment is widely used to resolve alkalinity issues and implement sustainable management for bauxite residue disposal areas (BRDAs). Amended BRDAs under natural conditions suffer from long-term erosion processes. Nevertheless, the effect of erosion on amendment efficacy is rarely assessed. Read More

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Spatial and temporal variation characteristics of atmospheric NO and SO in the Beijing-Tianjin-Hebei region before and after the COVID-19 outbreak.

Air Qual Atmos Health 2021 Apr 2:1-14. Epub 2021 Apr 2.

College of Resource Environment and Tourism, Capital Normal University, Beijing, 100048 China.

Emergency response mechanisms were activated throughout China during the COVID-19 outbreak. It is different from the temporary, partial, and limited pollution control measures taken to ensure the regional environmental quality during several important events such as the 2008 Beijing Olympic Games and the 2014 Asia-Pacific Economic Cooperation (APEC). During the COVID-19 epidemic period, extensive movement of people and almost all unnecessary industrial production (necessary industrial production refers to the production of food, epidemic prevention materials, etc. Read More

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Capacity of a Radio Vortex Communication System Using a Partial Angular Aperture Receiving Scheme under the Horizontal Non-Kolmogorov Model.

Sensors (Basel) 2021 Mar 4;21(5). Epub 2021 Mar 4.

School of Communication and Information Engineering, Shanghai University, Shanghai 200444, China.

A partial receiving scheme based on limited angular aperture multi-beam receiving and demultiplexing can solve the difficulty caused by the divergence of the vortex beam in the conventional whole beam receiving scheme and realize the long-distance transmission of the vortex wave. The propagation of the radio vortex beam in atmospheric turbulence is of significant importance in theoretical study and practical applications. In this paper, the influence of atmospheric turbulence on the performance of a radio vortex (RV) communication system based on a partial angular aperture receiving (PAAR) scheme under the horizontal non-Kolmogorov channel model is studied. Read More

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Long-term effects of elevated pCO levels on the expression of Chaoborus-induced defences in Daphnia pulex.

Zoology (Jena) 2021 Feb 28;146:125909. Epub 2021 Feb 28.

Department of Animal Ecology, Evolution & Biodiversity, Ruhr-University Bochum, NDEF, Universitaetsstraße 150, D-44780 Bochum, Germany. Electronic address:

Increased carbon dioxide from fossil fuel combustion results in an enrichment of CO in the global carbon cycle. Recent evidence indicates that rising atmospheric CO impacts the partial pressure of carbon dioxide (pCO) in freshwaters. This affects freshwater biota by disrupting chemical communication between predator and prey. Read More

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February 2021

Impact of Singapore's COVID-19 confinement on atmospheric CO fluxes at neighborhood scale.

Authors:
Erik Velasco

Urban Clim 2021 May 21;37:100822. Epub 2021 Mar 21.

385 Pasir Panjang Rd., 118719, Singapore.

Singapore entered a two-month partial lockdown in April 2020 to curb the spread of COVID-19. The imposed measures in addition to contain the virus spread, cut the emissions of greenhouse gases as many economic activities stopped across the city. The advice of stay-at-home changed the pattern of carbon dioxide (CO) emissions within the community. Read More

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Declined trend in herbaceous plant green-up dates on the Qinghai-Tibetan Plateau caused by spring warming slowdown.

Sci Total Environ 2021 Jun 2;772:145039. Epub 2021 Feb 2.

School of Applied Meteorology, Institute of Ecology, Jiangsu Key Laboratory of Agricultural Meteorology, Nanjing University of Information Science & Technology, Nanjing 210044, China. Electronic address:

There has been much debate on the temporal change trend and existence of a turning point in spring green-up date (GUD) of plants on the Qinghai-Tibetan Plateau (QTP). Most previous studies on the QTP used remote sensing data, which have large uncertainties. In this study, using a large amount of long-term ground observation data at 27 phenological stations across the QTP (1694 GUD records), we showed that on the whole, QTP herbaceous plant GUD insignificantly advanced during 1982-2017. Read More

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North polar trough formation due to in-situ erosion as a source of young ice in mid-latitudinal mantles on Mars.

Sci Rep 2021 Mar 25;11(1):6750. Epub 2021 Mar 25.

External Geodynamics and Hydrogeology Group, Department of Geology, Autonomous University of Barcelona, 08193, Bellaterra, Barcelona, Spain.

The clockwise spiral of troughs marking the Martian north polar plateau forms one of the planet's youngest megastructures. One popular hypothesis posits that the spiral pattern resulted as troughs underwent poleward migration. Here, we show that the troughs are extensively segmented into enclosed depressions (or cells). Read More

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Impacts of Changes in Atmospheric O on Human Physiology. Is There a Basis for Concern?

Front Physiol 2021 2;12:571137. Epub 2021 Mar 2.

Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of California, San Diego, La Jolla, CA, United States.

Concern is often voiced over the ongoing loss of atmospheric O. This loss, which is caused by fossil-fuel burning but also influenced by other processes, is likely to continue at least for the next few centuries. We argue that this loss is quite well understood, and the eventual decrease is bounded by the fossil-fuel resource base. Read More

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Improving the efficiency of urea-based fertilization leading to reduction in ammonia emission.

Sci Total Environ 2021 Jun 30;771:145483. Epub 2021 Jan 30.

Grupa Azoty Zakłady Azotowe "Puławy" S.A., Tysiąclecia Państwa Polskiego 13, 24-110 Puławy, Poland.

A problematic issue in agriculture is the high quantity of ammonia being released resulting in a partial loss of the nitrogen which is contained in urea fertilizers. Alignment with European Union legislation on the regulation of ammonia emission from mineral fertilizers after 2030, urea fertilizers with reduced ammonia emissions by at least 30% will be allowed to remain in use. Currently, laboratory and field tests are carried out to assess the effectiveness of inhibiting nitrogen losses from urea fertilizers. Read More

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Extreme gradients in CO losses downstream of karstic springs.

Sci Total Environ 2021 Mar 1;778:146099. Epub 2021 Mar 1.

Department of Geography and Geosciences, Schlossgarten 5, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Germany.

Rivers are significant sources of CO to the atmosphere, and karstic watersheds are particularly important in this respect due to their large availability of inorganic carbon. This study examines characteristics of dissolved inorganic carbon (DIC) and excess partial pressures of CO (epCO) in the source springs and headwaters of four watersheds in a Central European karstic region, via dissolved inorganic carbon concentration and stable carbon isotope measurements. Our results show the most C-depleted δC values at the source springs, which become rapidly enriched downstream due to CO degassing. Read More

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Integrating Transcriptomics and Metabolomics to Characterize Metabolic Regulation to Elevated CO in Chlamydomonas Reinhardtii.

Mar Biotechnol (NY) 2021 Apr 10;23(2):255-275. Epub 2021 Mar 10.

Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 106 Nanjing Road, Qingdao, 266071, China.

With atmospheric CO increasing, a large amount of CO is absorbed by oceans and lakes, which changes the carbonate system and affects the survival of aquatic plants, especially microalgae. The main aim of our study was to explore the responses of Chlamydomonas reinhardtii (Chlorophyceae) to elevated CO by combined transcriptome and metabolome analysis under three different scenarios: control (CK, 400 ppm), short-term elevated CO (ST, 1000 ppm), and long-term elevated CO (LT, 1000 ppm). The transcriptomic data showed moderate changes between ST and CK. Read More

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The effect of H : N ratio on the NH synthesis rate and on process economics over the CoMoN catalyst.

Faraday Discuss 2021 Mar 4. Epub 2021 Mar 4.

Department of Chemical Engineering, Middle East Technical University, Ankara, 06800, Turkey.

In this study, the process economics of ammonia synthesis over Co3Mo3N was investigated by searching for an optimum feed stoichiometry. From ammonia synthesis rate measurements at atmospheric pressure and 400 °C over Co3Mo3N, it was found that the rate was independent of H2 : N2 stoichiometry for stoichiometries above 0.5 : 1. Read More

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Recommendations for offline combustion-based nitrogen isotopic analysis of silicate minerals and rocks.

Rapid Commun Mass Spectrom 2021 May;35(10):e9075

Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, T6G 2E3, Canada.

Rationale: Due to isotope fractionations during partial nitrogen release from minerals and rocks, the complete extraction of nitrogen for analysis is crucial to ensure high-quality nitrogen isotopic data. However, the appropriate nitrogen extraction conditions (e.g. Read More

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Coalescence-Induced Jumping Droplets on Nanostructured Biphilic Surfaces with Contact Electrification Effects.

ACS Appl Mater Interfaces 2021 Mar 25;13(9):11470-11479. Epub 2021 Feb 25.

Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong.

Benefitting from the coalescence-induced droplet jumping on superhydrophobic surfaces, the condensing droplets on heat exchangers can be removed efficiently, significantly improving the condensation heat-transfer performance of various thermal applications. However, the enhancement of droplet jumping height and self-removal to further improve the condensation heat-transfer performance of the thermal applications remains a challenge due to considerable interfacial adhesion caused by the inevitable partial-Wenzel state condensing droplets on superhydrophobic surfaces. In this study, a biphilic nanostructure is developed to effectively improve the droplet jumping height by decreasing the interfacial adhesion with the formation of Cassie-like droplets. Read More

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Tolerance of two anhydrobiotic tardigrades and to hypomagnetic conditions.

PeerJ 2021 2;9:e10630. Epub 2021 Feb 2.

Department of Animal Taxonomy and Ecology/Faculty of Biology, Adam Mickiewicz University of Poznan, Poznań, Poland.

The open space is a hostile environment for all lifeforms not only due to vacuum, high radiation, low atmospheric pressure, and extremely low temperature, but also the absence of the geomagnetic field. The geomagnetic field protects Earth mainly from corpuscular radiation, that is, solar wind and cosmic radiation, but above all it influences organisms, including their cells, tissues and organs. Moreover, numerous studies conducted on plants and animals confirmed that hypomagnetic conditions (the term referring to all situations when the magnetic field is weaker than the typical geomagnetic field) have significant influence on the metabolism of living organisms. Read More

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February 2021

Cardiorespiratory Response and Power Output During Submaximal Exercise in Normobaric Versus Hypobaric Hypoxia: A Pilot Study Using a Specific Chamber that Controls Environmental Factors.

High Alt Med Biol 2021 Feb 16. Epub 2021 Feb 16.

Graduate School Department of Interdisciplinary Research, University of Yamanashi, Kofu, Japan.

Takezawa, Toshihiro, Shohei Dobashi, and Katsuhiro Koyama. Cardiorespiratory response and power output during submaximal exercise in normobaric versus hypobaric hypoxia: a pilot study using a specific chamber that controls environmental factors. 16:000-000, 2021. Read More

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February 2021

Precipitation of dopants on acceptor-doped LaMnO revealed by defect chemistry from first principles.

J Chem Phys 2021 Feb;154(6):064702

Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.

Perovskite oxides degrade at elevated temperatures while precipitating dopant-rich particles on the surface. A knowledge-based improvement of surface stability requires a fundamental and quantitative understanding of the dopant precipitation mechanism on these materials. We propose that dopant precipitation is a consequence of the variation of dopant solubility between calcination and operating conditions in solid oxide fuel cells (SOFCs) and electrolyzer cells (SOECs). Read More

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February 2021

Electron dose rate and oxygen depletion protect zebrafish embryos from radiation damage.

Radiother Oncol 2021 Feb 13;158:7-12. Epub 2021 Feb 13.

OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Germany; Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiation Physics, Germany. Electronic address:

Background And Purpose: In consequence of a previous study, where no protecting proton Flash effect was found for zebrafish embryos, potential reasons and requirements for inducing a Flash effect should be investigated with higher pulse dose rate and partial oxygen pressure (pO) as relevant parameters.

Materials And Methods: The experiments were performed at the research electron accelerator ELBE, whose variable pulse structure enables dose delivery as electron Flash and quasi-continuously (reference irradiation). Zebrafish embryos were irradiated with ~26 Gy either continuously at a dose rate of ~6. Read More

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February 2021

Effect of Oxygen Mole Fraction on Static Properties of Pressure-Sensitive Paint.

Sensors (Basel) 2021 Feb 4;21(4). Epub 2021 Feb 4.

Department of Aerospace Engineering, Tohoku University, Sendai 980-8579, Japan.

The effects of the oxygen mole fraction on the static properties of pressure-sensitive paint (PSP) were investigated. Sample coupon tests using a calibration chamber were conducted for poly(hexafluoroisopropyl methacrylate)-based PSP (PHFIPM-PSP), polymer/ceramic PSP (PC-PSP), and anodized aluminum PSP (AA-PSP). The oxygen mole fraction was set to 0. Read More

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February 2021

Seasonal variations in levels of human thyroid-stimulating hormone and thyroid hormones: a meta-analysis.

Chronobiol Int 2021 Mar 3;38(3):301-317. Epub 2021 Feb 3.

Department for Experimental Physiology and Pharmacology, Almazov National Medical Research Centre, St. Petersburg, Russia.

Seasonal dynamics in biological functions of mammals is regulated by melatonin-mediated circannual fluctuations in the secretion of thyroid-stimulating hormone (TSH) and thyroid hormones. Most anatomical and molecular structures responsive to photoperiod and melatonin secretion changes and the associated receptors are preserved in modern humans. This work aimed to determine the seasonal dynamics of TSH and thyroid hormone levels (total triiodothyronine (T3), free triiodothyronine (FT3), thyroxine (T4), free thyroxine (FT4) and to investigate the dependence of these variations on gender, age and amplitude of meteorological fluctuations. Read More

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Intraspecific variation in multiple trait responses of Alexandrium ostenfeldii towards elevated pCO.

Harmful Algae 2021 01 15;101:101970. Epub 2021 Jan 15.

Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB Wageningen, Netherlands.

Dissolved oceanic CO concentrations are rising as result of increasing atmospheric partial pressure of CO (pCO), which has large consequences for phytoplankton. To test how higher CO availability affects different traits of the toxic dinoflagellate Alexandrium ostenfeldii, we exposed three strains of the same population to 400 and 1,000 µatm CO, and measured traits including growth rate, cell volume, elemental composition, C fractionation, toxin content, and volatile organic compounds (VOCs). Strains largely increased their growth rates and particulate organic carbon and nitrogen production with higher pCO and showed significant changes in their VOC profile. Read More

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January 2021

Polycyclic Aromatic Hydrocarbons in the Atmosphere near the Great Lakes: Why Do Their Concentrations Vary?

Authors:
Ronald A Hites

Environ Sci Technol 2021 Jan 26. Epub 2021 Jan 26.

O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana 474015, United States.

Polycyclic aromatic hydrocarbon (PAH) concentrations were measured in atmospheric samples collected at five sites near the shores of the North American Great Lakes once every 12 days from 1997 to 2018 (inclusive). These data were analyzed using multiple linear regression statistics to isolate the environmental variables controlling these PAH concentrations. About 74% of the variability is related to the number of people living and working within 25 km of the sampling site. Read More

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January 2021