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The COVID-19 stay-at-home orders issued in the United States caused significant reductions in traffic and economic activities. To understand the pandemic's perturbations on US emissions and impacts on urban air quality, we developed near-real-time bottom-up emission inventories based on publicly available energy and economic datasets, simulated the emission changes in a chemical transport model, and evaluated air quality impacts against various observations. The COVID-19 pandemic affected US emissions across broad-based energy and economic sectors and the impacts persisted to 2021. Compared with 2019 business-as-usual emission scenario, COVID-19 perturbations resulted in annual decreases of 10-15% in emissions of ozone (O3) and fine particle (PM2.5) gas-phase precursors, which are about two to four times larger than long-term annual trends during 2010-2019. While significant COVID-induced reductions in transportation and industrial activities, particularly in April-June 2020, resulted in overall national decreases in air pollutants, meteorological variability across the nation led to local increases or decreases of air pollutants, and mixed air quality changes across the United States between 2019 and 2020. Over a full year (April 2020 to March 2021), COVID-induced emission reductions led to 3-4% decreases in national population-weighted annual fourth maximum of daily maximum 8-h average O3 and annual PM2.5. Assuming these emission reductions could be maintained in the future, the result would be a 4-5% decrease in premature mortality attributable to ambient air pollution, suggesting that continued efforts to mitigate gaseous pollutants from anthropogenic sources can further protect human health from air pollution in the future.
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Establishing mineral dust impacts on Earth's systems requires numerical models of the dust cycle. Differences between dust optical depth (DOD) measurements and modelling the cycle of dust emission, atmospheric transport, and deposition of dust indicate large model uncertainty due partially to unrealistic model assumptions about dust emission frequency. Calibrating dust cycle models to DOD measurements typically in North Africa, are routinely used to reduce dust model magnitude. This calibration forces modelled dust emissions to match atmospheric DOD but may hide the correct magnitude and frequency of dust emission events at source, compensating biases in other modelled processes of the dust cycle. Therefore, it is essential to improve physically based dust emission modules. Here we use a global collation of satellite observations from previous studies of dust emission point source (DPS) dichotomous frequency data. We show that these DPS data have little-to-no relation with MODIS DOD frequency. We calibrate the albedo-based dust emission model using the frequency distribution of those DPS data. The global dust emission uncertainty constrained by DPS data (±3.8 kg m-2 y-1) provides a benchmark for dust emission model development. Our calibrated model results reveal much less global dust emission (29.1 ± 14.9 Tg y-1) than previous estimates, and show seasonally shifting dust emission predominance within and between hemispheres, as opposed to a persistent North African dust emission primacy widely interpreted from DOD measurements. Earth's largest dust emissions, proceed seasonally from East Asian deserts in boreal spring, to Middle Eastern and North African deserts in boreal summer and then Australian shrublands in boreal autumn-winter. This new analysis of dust emissions, from global sources of varying geochemical properties, have far-reaching implications for current and future dust-climate effects. For more reliable coupled representation of dust-climate projections, our findings suggest the need to re-evaluate dust cycle modelling and benefit from the albedo-based parameterisation.
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A new dynamical core, known as the Finite-Volume Cubed-Sphere (FV3) and developed at both NASA and NOAA, is used in NOAA's Global Forecast System (GFS) and in limited-area models for regional weather and air quality applications. NOAA has also upgraded the operational FV3GFS to version 16 (GFSv16), which includes a number of significant developmental advances to the model configuration, data assimilation, and underlying model physics, particularly for atmospheric composition to weather feedback. Concurrent with the GFSv16 upgrade, we couple the GFSv16 with the Community Multiscale Air Quality (CMAQ) model to form an advanced version of the National Air Quality Forecasting Capability (NAQFC) that will continue to protect human and ecosystem health in the US. Here we describe the development of the FV3GFSv16 coupling with a "state-of-the-science" CMAQ model version 5.3.1. The GFS-CMAQ coupling is made possible by the seminal version of the NOAA-EPA Atmosphere-Chemistry Coupler (NACC), which became a major piece of the next operational NAQFC system (i.e., NACC-CMAQ) on 20 July 2021. NACC-CMAQ has a number of scientific advancements that include satellite-based data acquisition technology to improve land cover and soil characteristics and inline wildfire smoke and dust predictions that are vital to predictions of fine particulate matter (PM2.5) concentrations during hazardous events affecting society, ecosystems, and human health. The GFS-driven NACC-CMAQ model has significantly different meteorological and chemical predictions compared to the previous operational NAQFC, where evaluation of NACC-CMAQ shows generally improved near-surface ozone and PM2.5 predictions and diurnal patterns, both of which are extended to a 72 h (3 d) forecast with this system.
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In this work, we use observations and experimental emissions in a version of NOAA's National Air Quality Forecasting Capability to show that the COVID-19 economic slowdown led to disproportionate impacts on near-surface ozone concentrations across the contiguous U.S. (CONUS). The data-fusion methodology used here includes both U.S. EPA Air Quality System ground and the NASA Aura satellite Ozone Monitoring Instrument (OMI) NO2 observations to infer the representative emissions changes due to the COVID-19 economic slowdown in the U.S. Results show that there were widespread decreases in anthropogenic (e.g., NOx) emissions in the U.S. during March-June 2020, which led to widespread decreases in ozone concentrations in the rural regions that are NOx-limited, but also some localized increases near urban centers that are VOC-limited. Later in June-September, there were smaller decreases, and potentially some relative increases in NOx emissions for many areas of the U.S. (e.g., south-southeast) that led to more extensive increases in ozone concentrations that are partly in agreement with observations. The widespread NOx emissions changes also alters the O3 photochemical formation regimes, most notably the NOx emissions decreases in March-April, which can enhance (mitigate) the NOx-limited (VOC-limited) regimes in different regions of CONUS. The average of all AirNow hourly O3 changes for 2020-2019 range from about +1 to -4 ppb during March-September, and are associated with predominantly urban monitoring sites that demonstrate considerable spatiotemporal variability for the 2020 ozone changes compared to the previous five years individually (2015-2019). The simulated maximum values of the average O3 changes for March-September range from about +8 to -4 ppb (or +40 to -10%). Results of this work have implications for the use of widespread controls of anthropogenic emissions, particularly those from mobile sources, used to curb ozone pollution under the current meteorological and climate conditions in the U.S.
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Coastal regions have historically represented a significant challenge for air quality investigations due to water-land boundary transition characteristics and a paucity of measurements available over water. Prior studies have identified the formation of high levels of ozone over water bodies, such as the Chesapeake Bay, that can potentially recirculate back over land to significantly impact populated areas. Earth-observing satellites and forecast models face challenges in capturing the coastal transition zone where small-scale meteorological dynamics are complex and large changes in pollutants can occur on very short spatial and temporal scales. An observation strategy is presented to synchronously measure pollutants 'over-land' and 'over-water' to provide a more complete picture of chemical gradients across coastal boundaries for both the needs of state and local environmental management and new remote sensing platforms. Intensive vertical profile information from ozone lidar systems and ozonesondes, obtained at two main sites, one over land and the other over water, are complemented by remote sensing and in-situ observations of air quality from ground-based, airborne (both personned and unpersonned), and shipborne platforms. These observations, coupled with reliable chemical transport simulations, such as the NOAA National Air Quality Forecast Capability (NAQFC), are expected to lead to a more fully characterized and complete land-water interaction observing system that can be used to assess future geostationary air quality instruments, such as the NASA Tropospheric Emissions: Monitoring of Pollution (TEMPO) as well as current low earth orbiting satellites, such as the European Space Agency's Sentinel 5-Precursor (S5-P) with its Tropospheric Monitoring Instrument (TROPOMI).
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The varied answers to the question "What is a species?" provoke more than lively debates in academic circles. They pose practical problems for law enforcement. Commercial wildlife trade threatens many primate species and is regulated through such laws and international agreements as the U.S. Endangered Species Act and the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Enforcing legislation relies on the ability to identify when violations occur. Species-defining characters may not be preserved in wildlife trade items. For example, pelage patterns and behavioral characters (e.g., vocalizations) are absent from skulls. Accordingly, identifying victims of illegal trade can be difficult, which hinders enforcement. Moreover, identifying new species and "splitting" of currently recognized species can result in enforcement lags and regulatory loopholes. Although such negative consequences should not hinder scientific advancement, we suggest that they be considered by primate taxonomists and provide recommendations to prevent unintended conservation consequences.
Assuntos
Animais Selvagens , Espécies em Perigo de Extinção/legislação & jurisprudência , Primatas , Animais , Conservação dos Recursos Naturais , Ciências Forenses , Aplicação da Lei , Estados UnidosRESUMO
Abstract The development and characterization of a new cell line, derived from the ovary of Largemouth Bass Micropterus salmoides, is described. Gonad tissue was collected from Largemouth Bass that were electrofished from Oneida Lake, New York. The tissue was processed and grown in culture flasks at approximately 22°C for more than 118 passages during an 8-year period from 2004 to 2011. The identity of these cells as Largemouth Bass origin was confirmed by sequencing a portion of the cytochrome b gene. Growth rate at three different temperatures was documented. The cell line was susceptible to Largemouth Bass virus (LMBV) and its replication was compared with that of Bluegill Lepomis macrochirus fry (BF-2), one of the cell lines recommended for LMBV isolation by the American Fisheries Society Fish Health Section Blue Book. Quantitative PCR results from the replication trial showed the BF-2 cell line produced approximately 10-fold more LMBV copies per cell than the new Largemouth Bass cell line after 6 d, while the titration assay showed similar quantities in each cell line after 1 week. Received February 18, 2014; accepted April 16, 2014.
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Bass , Suscetibilidade a Doenças/veterinária , Animais , Linhagem Celular , Infecções por Vírus de DNA , Doenças dos Peixes , PerciformesRESUMO
We report the recent emergence of a novel beak and feather disease virus (BFDV) genotype in the last remaining wild population of the critically endangered Orange-bellied Parrot (Neophema chrysogaster). This virus poses a significant threat to the recovery of the species and potentially its survival in the wild. We used PCR to detect BFDV in the blood of three psittacine beak and feather disease (PBFD)-affected wild Orange-bellied Parrot fledglings captured as founders for an existing captive breeding recovery program. Complete BFDV genome sequence data from one of these birds demonstrating a 1,993-nucleotide-long read encompass the entire circular genome. Maximum-likelihood (ML) and neighbor-joining (NJ) phylogenetic analysis supported the solitary position of this viral isolate in a genetically isolated branch of BFDV. On Rep gene sequencing, a homologous genotype was present in a second wild orange-bellied parrot and the third bird was infected with a distantly related genotype. These viruses have newly appeared in a population that has been intensively monitored for BFDV for the last 13 yr. The detection of two distinct lineages of BFDV in the remnant wild population of Orange-bellied Parrots, consisting of fewer than 50 birds, suggests a role for other parrot species as a reservoir for infection by spillover into this critically endangered species. The potential for such a scenario to contribute to the extinction of a remnant wild animal population is supported by epidemiologic theory.
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Doenças das Aves/virologia , Infecções por Circoviridae/veterinária , Circovirus/isolamento & purificação , Espécies em Perigo de Extinção , Papagaios , Animais , Animais Selvagens , Austrália/epidemiologia , Doenças das Aves/epidemiologia , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/virologiaRESUMO
Fourier-transform infrared spectroscopy (FTIR), discriminate analysis, X-ray fluorescence spectrometry (XRF), and stereoscopic microscopy were used to separate black coral forensic evidence items from similarly appearing items manufactured from plastics, bovid keratin, and mangrove wood. In addition, novel observations were made of bromine and iodine relationships in black coral that have not been previously reported.
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Antozoários/química , Animais , Bromo/análise , Caseínas , Comércio/legislação & jurisprudência , Conservação dos Recursos Naturais/legislação & jurisprudência , Análise Discriminante , Fraude/legislação & jurisprudência , Iodo/análise , Queratinas , Microscopia , Plásticos , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Here we present methods for distinguishing tail hairs of African elephants (Loxodonta africana), Asian elephants (Elephas maximus), and giraffes (Giraffa camelopardalis) from forensic contexts. Such hairs are commonly used to manufacture jewelry artifacts that are often sold illegally in the international wildlife trade. Tail hairs from these three species are easily confused macroscopically, and morphological methods for distinguishing African and Asian tail hairs have not been published. We used cross section analysis and light microscopy to analyze the tail hair morphology of 18 individual African elephants, 18 Asian elephants, and 40 giraffes. We found that cross-sectional shape, pigment placement, and pigment density are useful morphological features for distinguishing the three species. These observations provide wildlife forensic scientists with an important analytical tool for enforcing legislation and international treaties regulating the trade in elephant parts.
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Elefantes , Cabelo/ultraestrutura , Microscopia , Ruminantes , Especificidade da Espécie , Animais , Comércio/legislação & jurisprudência , Conservação dos Recursos Naturais/legislação & jurisprudência , Crime/legislação & jurisprudência , Ciências Forenses , Cor de Cabelo , Humanos , Microscopia Eletrônica de VarreduraRESUMO
Captive zebrafish (Danio rerio) exhibit a limited repertoire of mating behaviors, likely due to the somewhat unnatural environment of aquaria. Observations in their natural habitat led us to believe that a depth gradient within the mating setup would positively affect fish mating. By tilting the tank to produce a depth gradient, we observed novel behaviors along with a preference for oviposition in the shallow area. Although we did not see an increase in the likelihood of a pair of fish to mate, we did see an increase in the embryo output in both adults and juveniles. In the adults, tilting led to a significant increase in embryo production (436 +/- 35 tilted vs. 362 +/- 34 untilted; p < 0.05). A similar effect was seen in juvenile fish as they progressed through sexual maturity. These results suggest that tilting of mating cages in the laboratory setting will lead to demonstrable improvements in embryo production for zebrafish researchers, and highlights the possibility of other manipulations to increase fecundity.
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Comportamento Animal/fisiologia , Embrião não Mamífero/fisiologia , Reprodução/fisiologia , Comportamento Sexual Animal/fisiologia , Peixe-Zebra/fisiologia , Animais , Meio Ambiente , Feminino , Masculino , Natação , Peixe-Zebra/genéticaRESUMO
STUDY OBJECTIVE: To develop a rapid online test of graft liver function during liver transplantation. DESIGN: Prospective, observational study. SETTING: University hospital transplant unit. PATIENTS: 17 adult patients with end-stage liver disease who underwent liver transplantation surgery. INTERVENTIONS: Rocuronium infusion dose requirements and plasma concentrations to maintain constant levels of neuromuscular paralysis during three phases of liver transplantation and their relationship with early postoperative liver function tests were studied. MEASUREMENTS: Infusion dose requirements of rocuronium, assay of rocuronium plasma concentrations using gas chromatography-mass spectrometry, and intensity of neuromuscular blockade were measured. MAIN RESULTS: A 24% decrease in rocuronium infusion requirements was observed during the an-hepatic phase. Rocuronium requirement during the neohepatic phase was increased only modestly or remained unchanged in 14 of the 16 patients who had normal graft function in the immediate postoperative period. Rocuronium plasma concentrations for maintaining constant levels of paralysis were significantly lower during the neohepatic phase than during the paleohepatic and anhepatic phases, indicating that there is likely to be a change in pharmacodynamics during this phase. Significant reduction in rocuronium infusion requirements during the neohepatic phase was observed in the only patient who had poor graft function in the early postoperative stage, suggesting that the reduced infusion requirement to maintain a constant neuromuscular paralysis may be related to the functional state of the graft liver after reperfusion. CONCLUSIONS: A significant reduction in rocuronium infusion requirement during the neohepatic phase may be suggestive of impaired organ function after reperfusion of the graft liver. Rocuronium may serve as a potential online indicator of graft liver function during liver transplantation by measurement of its infusion requirements during transplantation.
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Androstanóis/sangue , Hepatopatias/cirurgia , Transplante de Fígado , Bloqueio Neuromuscular , Fármacos Neuromusculares não Despolarizantes/sangue , Adolescente , Adulto , Análise de Variância , Androstanóis/administração & dosagem , Androstanóis/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Infusões Intravenosas , Hepatopatias/sangue , Testes de Função Hepática , Transplante de Fígado/métodos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Fármacos Neuromusculares não Despolarizantes/administração & dosagem , Fármacos Neuromusculares não Despolarizantes/uso terapêutico , Período Pós-Operatório , Estudos Prospectivos , RocurônioRESUMO
Anaesthetic requirements for endovascular surgery for aortic, carotid and peripheral vascular disease are reviewed. Peculiarities of the surgery which may impinge on anaesthetic management are discussed together with the pre-operative assessment issues of particular relevance to patients with generalized vascular disease. The detailed anaesthetic management for carotid and aortic endovascular repair is addressed. The lowered peri-operative stress and general morbidity levels which occur with endovascular surgery allow sicker patients with greater risk factors to present for this type of surgery, thus increasing the challenges facing anaesthetists.