The Essential Role for Laboratory Studies in Atmospheric Chemistry

Laboratory studies of atmospheric chemistry characterize the nature of atmospherically relevant processes down to the molecular level, providing fundamental information used to assess how human activities drive environmental phenomena such as climate change, urban air pollution, ecosystem health, indoor air quality, and stratospheric ozone depletion. Laboratory studies have a central role in addressing the incomplete fundamental knowledge of atmospheric chemistry. This article highlights the evolving science needs for this community and emphasizes how our knowledge is far from complete, hindering our ability to predict the future state of our atmosphere and to respond to emerging global environmental change issues. Laboratory studies provide rich opportunities to expand our understanding of the atmosphere via collaborative research with the modeling and field measurement communities, and with neighboring disciplines

The Essential Role for Laboratory Studies in Atmospheric Chemistry

Laboratory studies of atmospheric chemistry characterize the nature of atmospherically relevant processes down to the molecular level, providing fundamental information used to assess how human activities drive environmental phenomena such as climate change, urban air pollution, ecosystem health, indoor air quality, and stratospheric ozone depletion. Laboratory studies have a central role in addressing the incomplete fundamental knowledge of atmospheric chemistry. This article highlights the evolving science needs for this community and emphasizes how our knowledge is far from complete, hindering our ability to predict the future state of our atmosphere and to respond to emerging global environmental change issues. Laboratory studies provide rich opportunities to expand our understanding of the atmosphere via collaborative research with the modeling and field measurement communities, and with neighboring disciplines

Researching COVID to enhance recovery (RECOVER) tissue pathology study protocol: Rationale, objectives, and design.

ImportanceSARS-CoV-2 infection can result in ongoing, relapsing, or new symptoms or organ dysfunction after the acute phase of infection, termed Post-Acute Sequelae of SARS-CoV-2 (PASC), or long COVID. The characteristics, prevalence, trajectory and mechanisms of PASC are poorly understood. The objectives of the Researching COVID to Enhance Recovery (RECOVER) tissue pathology study (RECOVER-Pathology) are to: (1) characterize prevalence and types of organ injury/disease and pathology occurring with PASC; (2) characterize the association of pathologic findings with clinical and other characteristics; (3) define the pathophysiology and mechanisms of PASC, and possible mediation via viral persistence; and (4) establish a post-mortem tissue biobank and post-mortem brain imaging biorepository.MethodsRECOVER-Pathology is a cross-sectional study of decedents dying at least 15 days following initial SARS-CoV-2 infection. Eligible decedents must meet WHO criteria for suspected, probable, or confirmed infection and must be aged 18 years or more at the time of death. Enrollment occurs at 7 sites in four U.S. states and Washington, DC. Comprehensive autopsies are conducted according to a standardized protocol within 24 hours of death; tissue samples are sent to the PASC Biorepository for later analyses. Data on clinical history are collected from the medical records and/or next of kin. The primary study outcomes include an array of pathologic features organized by organ system. Causal inference methods will be employed to investigate associations between risk factors and pathologic outcomes.DiscussionRECOVER-Pathology is the largest autopsy study addressing PASC among US adults. Results of this study are intended to elucidate mechanisms of organ injury and disease and enhance our understanding of the pathophysiology of PASC

Sustainable policy—key considerations for air quality and climate change

Air quality and climate change are inexorably linked from theiremission sources to their impacts on climate, human health, andecosystems, including agriculture. However, in globalenvironmental change and sustainability policies the linkbetween air quality and climate change is often ignored. Tofacilitate including the link between air pollution and climatechange in the policy process, three key considerations (1) mix ofemissions, (2) lifetime, and (3) benefits and trade-offs should betaken into account. These three key considerations will helpdecision makers understand how proposed policies may impactthe emissions of air pollutants and greenhouse gases and theirresulting impacts on climate, human health, and ecosystems,thus reducing unintended consequences and likely resulting inadditional economic and environmental benefits

The international global atmospheric chemistry (IGAC) project: Facilitating atmospheric chemistry research for 25 years

This paper outlines the scientific achievements and insights gained from the International Global Atmospheric Chemistry (IGAC) project, which has been jointly sponsored by the international Commission on Atmospheric Chemistry and Global Pollution (iCACGP) and the International Geosphere-Biosphere Programme (IGBP) since 1990. A short history of IGAC is followed by representative key scientific achievements. Over 25 years, IGAC has facilitated international scientific collaborations that have deepened the understanding of how atmospheric composition impacts air quality, climate change, and ecosystems from local to global scales. Activities fostered by IGAC show how the field of atmospheric chemistry has evolved from a focus on the atmosphere as a single natural compartment of the Earth system to an emphasis on its interactions with other Earth components, such as oceans, the cryosphere, the biosphere, and the impact of humans on atmospheric composition. Finally, one of IGAC’s significant accomplishments has been building scientific capacity and cooperation in the field of atmospheric chemistry around the globe, especially through its biennial science conferences. As part of IGBP, IGAC has contributed to improving the current state of knowledge of the Earth system and providing the scientific basis to suggest that we have entered the Anthropocene. IGAC will continue to play this role and expand its connections to the larger global change and sustainability research communities, capitalizing on the transition to Future Earth

New Directions: Toward a community emissions approach

International audienc

Flow Injection Analysis of H\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e2\u3c/sub\u3e in Natural Waters Using Acridinium Ester Chemiluminescence: Method Development and Optimization Using a Kinetic Model

Chemiluminescence (CL) of acridinium esters (AE) has found widespread use in analytical chemistry. Using the mechanism of the reaction of H2O2 with 10-methyl-9-(p-formylphenyl)acridinium carboxylate trifluoromethanesulfonate and a modified flow injection system, the reaction rates of each step in the mechanism were evaluated and used in a kinetic model to optimize the analysis of H2O2. Operational parameters for a flow injection analysis system (reagent pH, flow rate, sample volume, PMT settings) were optimized using the kinetic model. The system is most sensitive to reaction pH due to competition between AE hydrolysis and CL. The optimized system was used to determine H2O2 concentrations in natural waters, including rain, freshwater, and seawater. The lower limit of detection varied in natural waters, from 352 pM in open ocean seawater (mean, 779 pM ± 15.0%, RSD) to 58.1 nM in rain (mean, 6,340 nM ± 0.92%, RSD). The analysis is specific for H2O2 and is therefore of potential interest for atmospheric chemistry applications where organoperoxides have been reported in the presence of H2O2