Influence of Wildfire on Urban Ozone: An Observationally Constrained Box Modeling Study at a Site in the Colorado Front Range.

Increasing trends in biomass burning emissions significantly impact air quality in North America. Enhanced mixing ratios of ozone (O3) in urban areas during smoke-impacted periods occur through transport of O3 produced within the smoke or through mixing of pyrogenic volatile organic compounds (PVOCs) with urban nitrogen oxides (NOx = NO + NO2) to enhance local O3 production. Here, we analyze a set of detailed chemical measurements, including carbon monoxide (CO), NOx, and speciated volatile organic compounds (VOCs), to evaluate the effects of smoke transported from relatively local and long-range fires on O3 measured at a site in Boulder, Colorado, during summer 2020. Relative to the smoke-free period, CO, background O3, OH reactivity, and total VOCs increased during both the local and long-range smoke periods, but NOx mixing ratios remained approximately constant. These observations are consistent with transport of PVOCs (comprised primarily of oxygenates) but not NOx with the smoke and with the influence of O3 produced within the smoke upwind of the urban area. Box-model calculations show that local O3 production during all three periods was in the NOx-sensitive regime. Consequently, this locally produced O3 was similar in all three periods and was relatively insensitive to the increase in PVOCs. However, calculated NOx sensitivities show that PVOCs substantially increase O3 production in the transition and NOx-saturated (VOC-sensitive) regimes. These results suggest that (1) O3 produced during smoke transport is the main driver for O3 increases in NOx-sensitive urban areas and (2) smoke may cause an additional increase in local O3 production in NOx-saturated (VOC-sensitive) urban areas. Additional detailed VOC and NOx measurements in smoke impacted urban areas are necessary to broadly quantify the effects of wildfire smoke on urban O3 and develop effective mitigation strategies.

Liver transplantation for alcohol-related liver disease in the UK: revised UK Liver Advisory Group recommendations for referral.

Liver disease, of which liver cirrhosis is the most advanced stage, constitutes the fourth most common cause of life-years lost in men and women younger than 75 years in England, where mortality rates from liver disease have increased by 25% in the past decade. Alcohol consumption is the most common modifiable risk factor for disease progression in these individuals, but within the UK, there is substantial variation in the distribution, prevalence, and outcome of alcohol-related liver disease, and no equity of access to tertiary transplantation services. These revised recommendations were agreed by an expert panel convened by the UK Liver Advisory Group, with the purpose of providing consensus on referral for transplant assessment in patients with alcohol-related disease, and clarifying the terminology and definitions of alcohol use in liver injury. By standardising clinical management in these patients, it is hoped that there will be an improvement in the quality of care and better access to liver transplant assessment for patients with alcohol-related liver disease in the UK.

Monitoring Protein-RNA Interaction Dynamics in vivo at High Temporal Resolution using χCRAC.

The interaction between RNA-binding proteins (RBPs) and their RNA substrates exhibits fluidity and complexity. Within its lifespan, a single RNA can be bound by many different RBPs that will regulate its production, stability, activity, and degradation. As such, much has been done to understand the dynamics that exist between these two types of molecules. A particularly important breakthrough came with the emergence of 'cross-linking and immunoprecipitation' (CLIP). This technique allowed stringent investigation into which RNAs are bound by a particular RBP. In short, the protein of interest is UV cross-linked to its RNA substrates in vivo, purified under highly stringent conditions, and then the RNAs covalently cross-linked to the protein are converted into cDNA libraries and sequenced. Since its conception, many derivative techniques have been developed in order to make CLIP amenable to particular fields of study. However, cross-linking using ultraviolet light is notoriously inefficient. This results in extended exposure times that make the temporal study of RBP-RNA interactions impossible. To overcome this issue, we recently designed and built much-improved UV irradiation and cell harvesting devices. Using these new tools, we developed a protocol for time-resolved analyses of RBP-RNA interactions in living cells at high temporal resolution: Kinetic CRoss-linking and Analysis of cDNAs (χCRAC). We recently used this technique to study the role of yeast RBPs in nutrient stress adaptation. This manuscript provides a detailed overview of the χCRAC method and presents recent results obtained with the Nrd1 RBP.

Scientific assessment of background ozone over the U.S.: Implications for air quality management.

Ozone (O3) is a key air pollutant that is produced from precursor emissions and has adverse impacts on human health and ecosystems. In the U.S., the Clean Air Act (CAA) regulates O3 levels to protect public health and welfare, but unraveling the origins of surface O3 is complicated by the presence of contributions from multiple sources including background sources like stratospheric transport, wildfies, biogenic precursors, and international anthropogenic pollution, in addition to U.S. anthropogenic sources. In this report, we consider more than 100 published studies and assess current knowledge on the spatial and temporal distribution, trends, and sources of background O3 over the continental U.S., and evaluate how it inflattainment of the air quality standards. We conclude that spring and summer seasonal mean U.S. background O3 (USB O3), or O3 formed from natural sources plus anthropogenic sources in countries outside the U.S., is greatest at high elevation locations in the western U.S., with monthly mean maximum daily 8-hour average (MDA8) mole fractions approaching 50 parts per billion (ppb) and annual 4th highest MDA8s exceeding 60 ppb, at some locations. At lower elevation sites, e.g., along the West and East Coasts, seasonal mean MDA8 USB O3 is in the range of 20-40 ppb, with generally smaller contributions on the highest O3 days. The uncertainty in U.S. background O3 is around ±10 ppb for seasonal mean values and higher for individual days. Noncontrollable O3 sources, such as stratospheric intrusions or precursors from wildfires, can make significant contributions to O3 on some days, but it is challenging to quantify accurately these contributions. We recommend enhanced routine observations, focused fi studies, process-oriented modeling studies, and greater emphasis on the complex photochemistry in smoke plumes as key steps to reduce the uncertainty associated with background O3 in the U.S.

Insights into the hepatocellular carcinoma patient journey: results of the first global quality of life survey.

AIM: To better understand the hepatocellular carcinoma (HCC) patient journey, we conducted a patient survey across 13 countries. METHODS: The survey included closed- and open-ended questions developed using an iterative process to gather information on demographics, diagnosis and treatment. Patients self-selected or were directed to the online survey by their doctor. RESULTS: A total of 256 patients completed the survey. More than two-thirds (68%) felt they did not receive enough information about HCC at diagnosis. Treatments included oral anticancer therapy, transarterial chemoembolization (TACE), and selective internal radiation therapy (SIRT). A total of 81% receiving sorafenib, 45% receiving SIRT and 32% receiving TACE reported impaired quality-of-life (QoL). A total of 42, 19 and 0% of patients using sorafenib rated their current QoL as 'poor', 'good' and 'excellent', respectively; compared with SIRT (22, 33 and 6%) or TACE (11, 37 and 13%). CONCLUSION: Most patients with HCC require additional accessible information. People with incurable HCC require treatments that preserve QoL.

Guidelines on the management of abnormal liver blood tests.

These updated guidelines on the management of abnormal liver blood tests have been commissioned by the Clinical Services and Standards Committee (CSSC) of the British Society of Gastroenterology (BSG) under the auspices of the liver section of the BSG. The original guidelines, which this document supersedes, were written in 2000 and have undergone extensive revision by members of the Guidelines Development Group (GDG). The GDG comprises representatives from patient/carer groups (British Liver Trust, Liver4life, PBC Foundation and PSC Support), elected members of the BSG liver section (including representatives from Scotland and Wales), British Association for the Study of the Liver (BASL), Specialist Advisory Committee in Clinical Biochemistry/Royal College of Pathology and Association for Clinical Biochemistry, British Society of Paediatric Gastroenterology, Hepatology and Nutrition (BSPGHAN), Public Health England (implementation and screening), Royal College of General Practice, British Society of Gastrointestinal and Abdominal Radiologists (BSGAR) and Society of Acute Medicine. The quality of evidence and grading of recommendations was appraised using the AGREE II tool. These guidelines deal specifically with the management of abnormal liver blood tests in children and adults in both primary and secondary care under the following subheadings: (1) What constitutes an abnormal liver blood test? (2) What constitutes a standard liver blood test panel? (3) When should liver blood tests be checked? (4) Does the extent and duration of abnormal liver blood tests determine subsequent investigation? (5) Response to abnormal liver blood tests. They are not designed to deal with the management of the underlying liver disease.

Disease burden and costs from excess alcohol consumption, obesity, and viral hepatitis: fourth report of the Lancet Standing Commission on Liver Disease in the UK.

This report contains new and follow-up metric data relating to the eight main recommendations of the Lancet Standing Commission on Liver Disease in the UK, which aim to reduce the unacceptable harmful consequences of excess alcohol consumption, obesity, and viral hepatitis. For alcohol, we provide data on alcohol dependence, damage to families, and the documented increase in alcohol consumption since removal of the above-inflation alcohol duty escalator. Alcoholic liver disease will shortly overtake ischaemic heart disease with regard to years of working life lost. The rising prevalence of overweight and obesity, affecting more than 60% of adults in the UK, is leading to an increasing liver disease burden. Favourable responses by industry to the UK Government's soft drinks industry levy have been seen, but the government cannot continue to ignore the number of adults being affected by diabetes, hypertension, and liver disease. New direct-acting antiviral drugs for the treatment of chronic hepatitis C virus infection have reduced mortality and the number of patients requiring liver transplantation, but more screening campaigns are needed for identification of infected people in high-risk migrant communities, prisons, and addiction centres. Provision of care continues to be worst in regions with the greatest socioeconomic deprivation, and deficiencies exist in training programmes in hepatology for specialist registrars. Firm guidance is needed for primary care on the use of liver blood tests in detection of early disease and the need for specialist referral. This report also brings together all the evidence on costs to the National Health Service and wider society, in addition to the loss of tax revenue, with alcohol misuse in England and Wales costing £21 billion a year (possibly up to £52 billion) and obesity costing £27 billion a year (treasury estimates are as high as £46 billion). Voluntary restraints by the food and drinks industry have had little effect on disease burden, and concerted regulatory and fiscal action by the UK Government is essential if the scale of the medical problem, with an estimated 63 000 preventable deaths over the next 5 years, is to be addressed.

Advanced chronic liver disease in the last year of life: a mixed methods study to understand how care in a specialist liver unit could be improved.

OBJECTIVE: To identify the limitations in palliative care provision in the last year of life for people with liver cirrhosis and potential barriers to and enablers of palliative care. DESIGN: Mixed methods, including a retrospective case note review, qualitative focus groups and individual interviews. SETTING: A tertiary referral liver centre in the south of England (UK). PARTICIPANTS: Purposively selected case notes of 30 people with cirrhosis who attended the tertiary referral liver centre and died during an 18-month period; a purposive sample of 22 liver health professionals who participated in either focus groups or individual interviews. PRIMARY AND SECONDARY OUTCOMES: Data collected from case notes included hospital admissions, documented discussions of prognosis and palliative care provision. Qualitative methods explored management of people with cirrhosis, and barriers to and enablers of palliative care. RESULTS: Participants had high rates of hospital admissions and symptom burden. Clinicians rarely discussed prognosis or future care preferences; they lacked the skills and confidence to initiate discussions. Palliative care provision occurred late because clinicians were reluctant to refer due to their perception that reduced liver function is reversible, poor understanding of the potential of a palliative approach; palliative care was perceived negatively by patients and families. CONCLUSIONS: People dying with cirrhosis have unpredictable trajectories, but share a common pathway of frequent admissions and worsening symptoms as death approaches. The use of clinical tools to identify the point of irreversible deterioration and joint working between liver services and palliative care may improve care for people with cirrhosis.

Kinetic CRAC uncovers a role for Nab3 in determining gene expression profiles during stress.

RNA-binding proteins play a key role in shaping gene expression profiles during stress, however, little is known about the dynamic nature of these interactions and how this influences the kinetics of gene expression. To address this, we developed kinetic cross-linking and analysis of cDNAs (χCRAC), an ultraviolet cross-linking method that enabled us to quantitatively measure the dynamics of protein-RNA interactions in vivo on a minute time-scale. Here, using χCRAC we measure the global RNA-binding dynamics of the yeast transcription termination factor Nab3 in response to glucose starvation. These measurements reveal rapid changes in protein-RNA interactions within 1 min following stress imposition. Changes in Nab3 binding are largely independent of alterations in transcription rate during the early stages of stress response, indicating orthogonal transcriptional control mechanisms. We also uncover a function for Nab3 in dampening expression of stress-responsive genes. χCRAC has the potential to greatly enhance our understanding of in vivo dynamics of protein-RNA interactions.Protein RNA interactions are dynamic and regulated in response to environmental changes. Here the authors describe 'kinetic CRAC', an approach that allows time resolved analyses of protein RNA interactions with minute time point resolution and apply it to gain insight into the function of the RNA-binding protein Nab3.

Quantifying TOLNet Ozone Lidar Accuracy during the 2014 DISCOVER-AQ and FRAPPÉ Campaigns.

The Tropospheric Ozone Lidar Network (TOLNet) is a unique network of lidar systems that measure high-resolution atmospheric profiles of ozone. The accurate characterization of these lidars is necessary to determine the uniformity of cross-instrument calibration. From July to August 2014, three lidars, the TROPospheric OZone (TROPOZ) lidar, the Tunable Optical Profiler for Aerosol and oZone (TOPAZ) lidar, and the Langley Mobile Ozone Lidar (LMOL), of TOLNet participated in the "Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality" (DISCOVER-AQ)mission and the "Front Range Air Pollution and Photochemistry Éxperiment" (FRAPPÉ)to measure ozone variations from the boundary layer to the top of the troposphere. This study presents the analysis of the intercomparison between the TROPOZ, TOPAZ, and LMOL lidars, along with comparisons between the lidars and other in situ ozone instruments including ozonesondes and a P-3B airborne chemiluminescence sensor. In terms of the range-resolving capability, the TOLNet lidars measured vertical ozone structures with an accuracy generally better than ±15% within the troposphere. Larger differences occur at some individual altitudes in both the near-field and far-field range of the lidar systems, largely as expected. In terms of column average, the TOLNet lidars measured ozone with an accuracy better than ±5% for both the intercomparison between the lidars and between the lidars and other instruments. These results indicate very good measurement accuracy for these three TOLNet lidars, making them suitable for use in air quality, satellite validation, and ozone modeling efforts.

Frequency and Impact of Summertime Stratospheric Intrusions over Maryland during DISCOVER-AQ (2011): New Evidence from NASA's GEOS-5 Simulations.

Aircraft observations and ozonesonde profiles collected on July 14 and 27, 2011, during the Maryland month-long DISCOVER-AQ campaign, indicate the presence of stratospheric air just above the planetary boundary layer (PBL). This raises the question of whether summer stratospheric intrusions (SIs) elevate surface ozone levels and to what degree they influence background ozone levels and contribute to ozone production. We used idealized stratospheric air tracers, along with observations, to determine the frequency and extent of SIs in Maryland during July 2011. On 4 of 14 flight days, SIs were detected in layers that the aircraft encountered above the PBL from the coincidence of enhanced ozone, moderate CO, and low moisture. Satellite observations of lower tropospheric humidity confirmed the occurrence of synoptic scale influence of SIs as do simulations with the GEOS-5 Atmospheric General Circulation Model. The evolution of GEOS-5 stratospheric air tracers agree with the timing and location of observed stratospheric influence and indicate that more than 50% of air in SI layers above the PBL had resided in the stratosphere within the previous 14 days. Despite having a strong influence in the lower free troposphere, these events did not significantly affect surface ozone, which remained low on intrusion days. The model indicates similar frequencies of stratospheric influence during all summers from 2009-2013. GEOS-5 results suggest that, over Maryland, the strong inversion capping the summer PBL limits downward mixing of stratospheric air during much of the day, helping to preserve low surface ozone associated with frontal passages that precede SIs.

Climate variability modulates western US ozone air quality in spring via deep stratospheric intrusions.

Evidence suggests deep stratospheric intrusions can elevate western US surface ozone to unhealthy levels during spring. These intrusions can be classified as 'exceptional events', which are not counted towards non-attainment determinations. Understanding the factors driving the year-to-year variability of these intrusions is thus relevant for effective implementation of the US ozone air quality standard. Here we use observations and model simulations to link these events to modes of climate variability. We show more frequent late spring stratospheric intrusions when the polar jet meanders towards the western United States, such as occurs following strong La Niña winters (Niño3.4<-1.0 °C). While El Niño leads to enhancements of upper tropospheric ozone, we find this influence does not reach surface air. Fewer and weaker intrusion events follow in the two springs after the 1991 volcanic eruption of Mt. Pinatubo. The linkage between La Niña and western US stratospheric intrusions can be exploited to provide a few months of lead time during which preparations could be made to deploy targeted measurements aimed at identifying these exceptional events.

High winter ozone pollution from carbonyl photolysis in an oil and gas basin.

The United States is now experiencing the most rapid expansion in oil and gas production in four decades, owing in large part to implementation of new extraction technologies such as horizontal drilling combined with hydraulic fracturing. The environmental impacts of this development, from its effect on water quality to the influence of increased methane leakage on climate, have been a matter of intense debate. Air quality impacts are associated with emissions of nitrogen oxides (NOx = NO + NO2) and volatile organic compounds (VOCs), whose photochemistry leads to production of ozone, a secondary pollutant with negative health effects. Recent observations in oil- and gas-producing basins in the western United States have identified ozone mixing ratios well in excess of present air quality standards, but only during winter. Understanding winter ozone production in these regions is scientifically challenging. It occurs during cold periods of snow cover when meteorological inversions concentrate air pollutants from oil and gas activities, but when solar irradiance and absolute humidity, which are both required to initiate conventional photochemistry essential for ozone production, are at a minimum. Here, using data from a remote location in the oil and gas basin of northeastern Utah and a box model, we provide a quantitative assessment of the photochemistry that leads to these extreme winter ozone pollution events, and identify key factors that control ozone production in this unique environment. We find that ozone production occurs at lower NOx and much larger VOC concentrations than does its summertime urban counterpart, leading to carbonyl (oxygenated VOCs with a C = O moiety) photolysis as a dominant oxidant source. Extreme VOC concentrations optimize the ozone production efficiency of NOx. There is considerable potential for global growth in oil and gas extraction from shale. This analysis could help inform strategies to monitor and mitigate air quality impacts and provide broader insight into the response of winter ozone to primary pollutants.

Magnitude, decadal changes, and impact of regional background ozone transported into the greater Houston, Texas, area.

Two independent analyses of the daily maximum 8 h average ozone concentrations measured during the high ozone season (May through October) at Continuous Ambient Monitoring Stations are used to quantify the regional background ozone transported into the Houston-Galveston-Brazoria (HGB) area. The dependence on wind direction is examined, and long-term trends are determined using measurements made between 1998 and 2012. Both analyses show that the regional background ozone has declined during periods of continental outflow: i.e., the conditions associated with most high ozone episodes in HGB. The changes in regional background ozone found for northeasterly and southeasterly flow are -0.50 ± 0.54 and -0.79 ± 0.65 (95% confidence limit) ppbv yr(-1), respectively, which correspond to decreases of ∼7-11 ppbv between 1998 and 2012. This finding is consistent with the summertime downward trend of -0.45 ppbv yr(-1) (range of sites: -0.87 to +0.07 ppbv yr(-1)) for ozone in the eastern U.S. between 1990 and 2010 reported by Cooper et al. and shows that changing background concentrations are at least partially responsible for the decreased surface ozone in the HGB area over the past decade. Baseline ozone concentrations in air flowing into Texas from the Gulf of Mexico have not changed significantly over this period.

Emollients, education and quality of life: the RCPCH care pathway for children with eczema.

OBJECTIVES: The Royal College of Paediatrics and Child Health (RCPCH) Science and Research Department was commissioned by the Department of Health to develop national care pathways for children with allergies. The eczema pathway focuses on defining the competences to improve the equity of care received by children with eczema. METHOD: The eczema pathway was developed by a multidisciplinary working group and was based on a comprehensive review of evidence. The pathway was reviewed by a broad group of stakeholders including paediatricians, allergists, dermatologists, specialist nurses, dietician, patients' representatives and approved by the Allergy Care Pathways Project Board and the RCPCH Clinical Standards Committee. It was also reviewed by a wide range of stakeholders. RESULTS: The results are presented in three sections: the evidence review, mapping and the core knowledge document. The various entry points to the ideal pathway of care are defined from self-care through to follow-up. There is considerable emphasis on good skin care and when allergy problems should be dealt with. The pathway algorithm and associated competences can be downloaded from http://www.rcpch.ac.uk/allergy/eczema. CONCLUSIONS: Effective eczema management is holistic and encompasses an assessment of severity and impact on quality of life, treatment of the inflamed epidermal skin barrier, recognition and treatment of infection and assessment and management of environmental and allergy triggers. Patient and family education which seeks to maximise understanding and concordance with treatment is also important in all children with eczema.

The RCPCH care pathway for children with urticaria, angio-oedema or mastocytosis: an evidence and consensus based national approach.

AIMS: The Royal College of Paediatrics and Child Health (RCPCH) Science and Research Department was commissioned by the Department of Health to develop national care pathways for children with allergies; the urticaria, angio-oedema or mastocytosis pathway is the fifth pathway. The pathways focus on defining the competences required to improve the equity of care received by children with allergic conditions. METHOD: The urticaria, angio-oedema or mastocytosis pathway was developed by a multidisciplinary working group and was based on a comprehensive review of evidence. The pathway was reviewed by a broad group of stakeholders including the public and approved by the Allergy Care Pathways Project Board and the RCPCH Clinical Standards Committee. RESULTS: Three pathways are described: urticaria with or without angio-oedema, angio-oedema without weals, and mastocytosis. The results are presented in four parts: evidence review, mapping, external review and core knowledge documents. Acute urticaria has many causes and is often not allergic in origin. It is frequently of relatively short duration and easily managed with antihistamines alone. However, at the other extreme, causes of chronic urticaria and angio-oedema are difficult to diagnose and treatment can be complex. Thus defining the competence required for each extreme is critical to ensure optimal care. The evidence review identified that allergy testing and thyroid function testing were helpful in the investigation of chronic urticaria, that increasing the dose of antihistamine was effective in treating urticaria and that ciclosporin A and prednisolone were effective second line treatments. CONCLUSIONS: From the common presentation of acute (intermittent) urticaria to the uncommon presentations of chronic urticaria, angio-oedema and cutaneous mastocytosis, this pathway is a tool to assist health professionals to differentiate and manage these conditions.