Mercury in Ringed Seals (Pusa hispida) from the Canadian Arctic in Relation to Time and Climate Parameters.

Mercury is found in Arctic marine mammals that are important in the diet of northern Indigenous peoples. The objectives of the present long-term study, spanning a 45-yr period, were to 1) investigate the temporal trends of total mercury (THg; muscle and liver) and selenium (Se; liver) in ringed seals (Pusa hispida) from different regions of the Canadian Arctic; and 2) examine possible relationships with age, diet, and climate parameters such as air temperature, precipitation, climatic indices, and ice-coverage. Ringed seals were collected by hunters in northern communities in the Beaufort Sea, Central Arctic, Eastern Baffin Island, Hudson Bay, and Ungava/Nunatsiavut regions (Canada) between 1972 and 2017. Mercury levels did not change through time in seal liver, but THg levels in muscle decreased in seals from Hudson Bay (-0.91%/yr) and Ungava/Nunatsiavut (-1.30%/yr). Carbon stable isotope values in seal muscle decreased significantly through time in 4 regions. Selenium-to-THg ratios were found to be >1 for all years and regions. Variation partitioning analyses across regions indicated that THg trends in seals were mostly explained by age (7.3-21.7%), climate parameters (3.5-12.5%), and diet (up to 9%); climate indices (i.e., Arctic and North Atlantic Oscillations, Pacific/North American pattern) explained the majority of the climate portion. The THg levels had a positive relationship with Arctic Oscillation for multiple regions. Associations of THg with air temperature, total precipitation, and sea-ice coverage, as well as with North Atlantic Oscillation and Pacific/North American pattern were found to vary with tissue type and geographical area. Environ Toxicol Chem 2020;39:2462-2474. © 2020 Her Majesty the Queen in Right of Canada. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Fisheries and Oceans Canada.

Spatio-temporal variations of licensed doctor distribution in China: measuring and mapping disparities.

BACKGROUND: The licensed doctor misdistribution is one of the major challenges faced by China. However, this subject remains underexplored as spatial distribution characteristics (such as spatial clustering patterns) have not been fully mapped out by existing studies. To fill the void, this study aims to explore the spatio-temporal dynamics and spatial clustering patterns of different subtypes of licensed doctors (i.e., clinicians, traditional Chinese medicine doctors, dentists, public health doctors, general practitioners) in China. METHODS: Data on the licensed doctor quantity and population during 2012-2016 was obtained from the National Health (and Family Planning) Yearbook. Functional boxplots were used to visualize and compare the temporal trends of densities of different subtypes of licensed doctors. This study adopted two complementary spatial statistics (space-time scan statistics and Moran's I statistics) to explore the spatio-temporal dynamics and spatial clustering patterns of licensed doctor distribution in China. The former was used to explore the spatial variations in the temporal trends of licensed doctor density during 2012-2016, and the latter was adopted to explore the spatial changing patterns of licensed doctor distribution during the research period. RESULTS: The results show that the densities of almost all subtypes of licensed doctors displayed upward trends during 2012-2016, though some provincial units were left behind. Besides, spatial distribution characteristics varied across different subtypes of licensed doctors, with the low-low cluster area of general practitioners being the largest. CONCLUSIONS: The misdistribution of licensed doctors is a global problem and China is no exception. In order to achieve a balanced distribution of licensed doctors, the government is suggested to introduce a series of measures, such as deliberative policy design and effective human resource management initiatives to educate, recruit, and retain licensed doctors and prevent a brain drain of licensed doctors from disadvantaged units.

Trends in statin utilization among adults with severe peripheral artery disease including critical limb ischemia in an integrated healthcare delivery system.

Evidence suggests that statin therapy in patients with peripheral artery disease (PAD) is beneficial yet use remains suboptimal. We examined trends in statin use, intensity, and discontinuation among adults aged ⩾ 40 years with incident severe PAD and a subset with critical limb ischemia (CLI) between 2002 and 2015 within an integrated healthcare delivery system. Discontinuation of statin therapy was defined as the first 90-day gap in treatment within 1 year following PAD diagnosis. We identified 11,059 patients with incident severe PAD: 31.1% (n = 3442) with CLI and 68.9% (n = 7617) without CLI. Mean (SD) age was 68.6 (11.3) years, 60.5% were male, 54.2% white, 23.2% Hispanic, and 16.2% black. Statin use in the year before diagnosis increased from 50.4% in 2002 to 66.0% in 2015 (CLI: 43.7% to 68.0%; without CLI: 53.1% to 64.2%, respectively). The proportion of patients on high-intensity statins increased from 7.3% in 2002 to 41.9% in 2015 (CLI: 7.2% to 39.4%; without CLI: 7.4% to 44.2%, respectively). Of the 40.5% (n = 4481) who were not on a statin in the year before diagnosis, 13.5% (n = 607) newly initiated therapy within 1 month (CLI: 10.1% (n = 150); without CLI: 15.3% (n = 457)). Following diagnosis, 12.5% (n = 660) discontinued statin therapy within 1 year (CLI: 15.5% (n = 202); without CLI: 11.5% (n = 458)). Although use of statins increased from 2002 to 2015, a substantial proportion of the overall PAD and CLI subpopulation remained untreated with statins, representing a significant treatment gap in a population at high risk for cardiovascular events and adverse limb outcomes.

Trends in surface water chemistry in afforested Welsh catchments recovering from acidification, 1991-2012.

A key criterion of the UK Government's policy on sustainable forest management is safeguarding the quality and quantity of water. Forests and forestry management practices can have profound effects on the freshwater environment. Poor forest planning or management can severely damage water resources at great cost to other water users; in contrast good management that restores and maintains the natural functions of woodland can benefit the whole aquatic ecosystem. Forests and forest management practices can affect surface water acidification. Monitoring of water chemistry in ten forest and two moorland acid-sensitive catchments in upland Wales commenced in 1991. The streams were selected to supplement the United Kingdom Upland Waters Monitoring Network (UWMN) with additional examples of afforested catchments. Analysis of 22 years of water chemistry data revealed trends indicative of recovery from acidification. Excess sulphate exhibited a significant coherent decline, accompanied by increases in pH and "charge-balance based" acid neutralising capacity (CB-ANC). Alkalinity and "alkalinity-based" acid neutralising capacity (AB-ANC) exhibited fewer trends, possibily due to the variable responses of the organic - carbonate species to increasing pH in these low alkalinity streams. Whilst total anthropogenic acidity declined, dissolved organic carbon and Nitrate-Nitrogen (NNO3) concentrations have risen, and the contribution of NNO3 to acidification has increased. Between-stream variability was analysed using Principal Component Analysis of the trend slopes. Hierarchical clustering of the changes in stream water chemistry indicated three distinct clusters with no absolute distinction between moorland and forest streams. Redundancy analysis was used to test for significant site-specific variables that explained differences in the trend slopes, with rainfall, crop age, base cation concentration and forest cover being significant explanatory variables.

Changing rate orders of race-gender heart disease death rates: An exploration of county-level race-gender disparities.

A holistic view of racial and gender disparities that simultaneously compares multiple groups can suggest associated underlying contextual factors. Therefore, to more comprehensively understand temporal changes in combined racial and gender disparities, we examine variations in the orders of county-level race-gender specific heart disease death rates by age group from 1973-2015. We estimated county-level heart disease death rates by race, gender, and age group (35-44, 45-54, 55-64, 65-74, 75-84, ≥ 85, and ≥ 35) from the National Vital Statistics System of the National Center for Health Statistics from 1973-2015. We then ordered these rates from lowest to highest for each county and year. The predominant national rate order (i.e., white women (WW) < black women (BW) < white men (WM) < black men (BM)) was most common in younger age groups. Inverted rates for black women and white men (WW

Chinese research into severe ulcerative colitis has increased in quantity and complexity.

AIM: To investigate the current state of research output from Chinese studies into severe ulcerative colitis (SUC) using a bibliometric analysis of publications. METHODS: The contents of the Chinese periodical databases WANFANG, VIP, and China National Knowledge Infrastructure were searched for all papers regarding UC or SUC published in last the 15 years (from 2001 to 2015). The number of publications in each year was recorded to assess the temporal trends of research output. All SUC related publications were downloaded and the complexity of this research was evaluated with methods described previously. The number of patients with SUC reported each year was recorded and their clinical characteristics were analyzed using information available in the relevant papers. RESULTS: There were 13499 publications regarding UC published in Chinese medical journals between 2001 and 2015, of which 201 focused on SUC. The number of publications increased rapidly with more than half of all papers being published in the most recent 5-year period. There was a significant increase in analytical studies and clinical trials over the study period (P < 0.01), with research into the management of SUC, included pharmacotherapy, nutrition support as well as surgery, predominating. Almost half (46.2%) of the observational analytical studies and clinical trials focused on Traditional Chinese Medicine, with little research on the efficacy of cyclosporin and infliximab in disease management. About 6222 patients with SUC were reported in the 201 SUC relevant papers, with a ratio of male/female of 1.38. The number of patients reported in each 5-year period significantly increased. The colectomy rate and short-term mortality rate were 7.7% and 0.8% respectively. The most commonly employed operation was total proctocolectomy with ileal pouch-anal anastomosis. CONCLUSION: The output and complexity of research related to SUC in China increased significantly over the previous 15 years, however few of these studies focused on salvage therapy.

Temporal trends in organic carbon content in the main Swiss rivers, 1974-2010.

Increases in dissolved organic carbon (DOC) concentrations have often been reported in rivers and lakes of the Northern Hemisphere over the last few decades. High-quality organic carbon (OC) concentration data have been used to study the change in DOC and total (TOC) organic carbon concentrations in the main rivers of Switzerland (Rhône, Rhine, Thur and Aar) between 1974 and 2010. These rivers are characterized by high discharge regimes (due to their Alpine origin) and by running in populated areas. Small long term trends (a general statistically significant decrease in TOC and a less clear increase in DOC concentrations), on the order of 1% of mean OC concentration per year, have been observed. An upward trend before 1999 reversed direction to a more marked downward trend from 1999 to 2010. Of the potential causes of OC temporal variation analysed (water temperature, dissolved reactive phosphorus and river discharge), only discharge explains a significant, albeit still small, part of TOC variability (8-31%), while accounting for barely 2.5% of DOC variability. Estimated anthropogenic TOC and DOC loads (treated sewage) to the rivers could account for a maximum of 4-20% of the temporal trends. Such low predictability is a good example of the limitations faced when studying causality and drivers behind small variations in complex systems. River export of OC from Switzerland has decreased significantly over the period. Since about 5.5% of estimated NEP of Switzerland is exported by the rivers, riverine OC fluxes should be taken into account in a detailed carbon budget of the country.

The spatial and temporal distribution of pollen in a room: forensic implications.

This paper presents two experimental studies that deal with the spatial and temporal distribution of pollen grains within a room of a domestic dwelling. The findings concur with the preliminary work of Morgan et al. [1] and provide greater detail as to the behaviour of pollen grains within indoor locations that are pertinent for forensic investigations. The spatial distribution of pollen in a room exhibits strong distance decay trends, with the majority of pollen recovered within 0.8m of its source. The pollen was found to persist in increasing quantities during the time the flowers were in the room. This study also shows that 20days after the flowers were removed, 25-32% of the original pollen was still present within the room. The influence of disturbance was investigated and whilst areas of high disturbance were found to retain less pollen than undisturbed locations, the influence of the proximity to source was a more dominant factor. These findings have significant implications for forensic investigation protocols, particularly the collection and interpretation phases of trace evidence analysis. The distribution of pollen around a room ensures that viable sources of trace pollen are available for transfer if contact is made between a location in the room and a suspect. The persistence of pollen many days after the flowers have been removed from a room indicates that many rooms in domestic dwellings will have distinctive assemblages that reflect the history of the flowers that have been displayed within that room in the past, and that these assemblages will persist and therefore be available for transfer. These preliminary findings indicate that investigation by forensic palynology in indoor domestic settings may well be an underutilised technique that has the potential to provide accurate and valuable intelligence and evidence for forensic enquiry.