Recent palaeolimnological change recorded in Lake Xiaolongwan, northeast China: Climatic versus anthropogenic forcing

Lake Xiaolongwan is a closed maar lake located in the Long Gang Volcanic Field, northeast China. Core XLW2 was collected in 2007 from the central region of the lake and provides a palaeoecological reconstruction over the past ca. 130 years (dated using radiometric methods: 210Pb and 137Cs). Diatom floristic changes and catchment productivity (carbon isotope ratios) were analysed within the core. Indicators of atmospheric pollution (XRF and SCP inventories) were also measured. Results show a marked transition from a dominant benthic assemblage to a planktonic one (increasing P:B ratios) starting after ca. 1940 AD, becoming most prominent after ca. 1980 AD (P:B > 1). Most notable floristic changes result from the increase in the planktonic species Discostella woltereckii. These changes are concomitant with increased temperature trends from the region and reconstructed temperature anomalies of the Northern Hemisphere. SCP concentrations and flux rates also increase after ca. 1950 AD, with highest values seen at ca. 1980 AD after which values decline. Normalised elemental geochemistry (e.g. Pb/Ti) also show marked changes after ca. 1970 AD, most likely derived from atmospheric deposition of Pb. The recent increase in D. woltereckii precedes anthropogenic contamination (Pb/Ti) at the site and persists after the decline in SCP concentrations. This suggests that the recent increases are driven by increased mean annual temperature trends. These temperature trends may be manifested as changes in ice cover persistence, a longer growing season and/or increased DOC at Lake Xiaolongwan: conditions for which planktonic species have a more competitive advantage

Lake sediment records of persistent organic pollutants and polycyclic aromatic hydrocarbons in Southern Siberia mirror the changing fortunes of the Russian economy over the past 70 years

Persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) have previously been detected in the surface sediments, water, and endemic organisms of Lake Baikal, a UNESCO World Heritage Site. The Selenga River is the primary source of freshwater to Lake Baikal, and transports pollutants accumulating in the Selenga River basin to the lake. Sources of POPs and PAHs in the Selenga River basin grew through the 20th century. In the present study, temporal changes in the concentrations of PAHs and POPs were reconstructed from two lakes in the Selenga River basin over the past 150 years using paleolimnological techniques. Increased concentrations in PAHs and PCBs were recorded initially in the 1930s. The 1940s–1980s was the period of greatest exposure to organic contamination, and concentrations of dichlorodiphenyltrichloroethane (DDT), polychlorinated biphenyls (PCBs), hexachlorocyclohexanes (HCHs) and many PAHs peaked between the 1960s and 1980s in the two lakes. Declines in concentrations and fluxes were recorded for most PAHs and POPs in the 1980s and 1990s. Temporal trends in concentrations of total and individual compounds/congeners of PAH, PCBs, and polybrominated diphenyl ethers (PBDEs) indicate the contribution of both local and regional sources of contamination in the 20th and 21st centuries. Temporal variations in contaminants can be linked to economic and industrial growth in the former USSR after World War II and the economic decline of Russia in the late-1980s and early-1990s, as well as global trends in industrialization and development during the mid-20th century

Previous Experiences with Epilepsy and Effectiveness of Information to Change Public Perception of Epilepsy

Differences with regard to the effectiveness of health information and attitude change are suggested between people with direct, behavioral experiences with a health topic and people with indirect, nonbehavioral experiences. The effects of three different methods of health education about epilepsy, frequently used in health education practice, are assessed in a pretest posttest design with control groups, controlling for experiences with epilepsy. Subjects were 132 students from teacher-training colleges. After all treatments, attitudes, and knowledge about epilepsy were changed in a positive way. Treatments were found to be equally effective. Before treatment, direct behavioral experiences were related to knowledge and a more positive attitude towards epilepsy. After treatment, subjects with direct behavioral experiences with epilepsy showed less change of attitude and knowledge as compared with subjects with indirect experiences. Direct experiences appear to restrain the processing of new information and attitude change

Climate change and the aquatic ecosystems of the Rwenzori Mountains, Uganda

The Rwenzori Mountains are home to one of the last remaining tropical icefields outside of the Andes. Over the last century, equatorial icefields of the East African highlands have been steadily shrinking but the precise climate tropical alpine glaciers remain unclear. More than a decade had passed since the last detailed measurements of glacial cover were made in the Rwenzori Mountains. Recent evidence from Kilimanjaro suggests that its icecap will disappear entirely by the year 2020(1). The Rwenzori glaciers contribute meltwater flows to aquatic ecosystems of the Rwenzori Mountains National Park, a Word Heritage Site featuring spectacular, rare Afroalpine flora and fauna, and are headwaters of the River Nile. With the overall aim of assessing the impact of recent climate change on alpine aquatic ecosystems of the Rwenzori Mountains, a collaborative, international research team led by the University College London (United Kingdom) and Makerere University (Uganda), and involving the Institut für Geographie from the University of Innsbruck (Austria) and Water Resources Management Department (Uganda) was assembled in order to pursue three primary scientific objectives: • to assess the magnitude of current glacial recession; • to assess the impact of glacial recession on alpine riverflow; and • to assess recent environmental change from observational datasets and available, environmental archives stored in lake sediment and glacial ice

Diatom community responses to long-term multiple stressors at Lake Gusinoye, Siberia

The information, practices and views in this article are those of the author(s) and do not necessarily reflect the opinion of the Royal Geographical Society (with IBG). © 2019 The Authors. Geo: Geography and Environment published by John Wiley & Sons Ltd and the Royal Geographical Society (with the Institute of British Geographers). Global freshwater systems are threatened by multiple anthropogenic stressors via impacts on ecological structure and function necessary to maintain their health. In order to properly manage freshwater ecosystems, we must have a better understanding of the ecological response to human-induced stressors, especially in multiple stressor environments. When long-term observational records are scarce or non-existent, paleolimnology provides a means to understanding ecological response to long-term stress. Lake Gusinoye is a large, deep lake in continental southeast Siberia, and has been subject to multiple human-induced stressors since the 19th century. Diatom assemblages since the late 17th century were reconstructed from a Lake Gusinoye sediment core to increase our understanding of the response of primary producer communities to centuries of environmental change. Records of anthropogenic contamination of Lake Gusinoye (as indicated by spheroidal carbonaceous particle, trace metal, and element records) indicate increases in regional and local development c. 1920. Diatom assemblages were initially dominated by Aulacoseira granulata, which declined beginning in the 18th century, likely as a response to hydrological change in the Gusinoye basin due to regional climate warming following the termination of the Little Ice Age (LIA). Significant diatom compositional turnover was observed since the 19th century at Lake Gusinoye. Since the early 20th century, Lake Gusinoye diatom assemblages have changed more profoundly as a result of multiple anthropogenic stressors, including nutrient influx, aquaculture, and wastewater discharge from the Gusinoozersk State Regional Power Plant. Recent diatom assemblages are dominated by Lindavia ocellata and nutrient-rich species, including Fragilaria crotonensis and Asterionella formosa. Evidence of continued nutrient enrichment at Lake Gusinoye is likely due to aquaculture in the lake, and suggests potential interactive effects of warming regional temperatures and increasing nutrients (eutrophication)

Aquarium Viromes: Viromes of Human-Managed Aquatic Systems

An aquarium ecosystem is home to many animal species providing conditions similar to native aquatic habitats but under highly controlled management. With a growing interest in understanding the interaction of microbiomes and resident animal health within aquarium environments, we undertook a metagenomic survey of viromes in seven aquarium systems with differing physicochemical and resident animal profiles. Our results show that a diverse array of viruses was represented in aquarium viromes, many of which were widespread in different aquarium systems (27 common viral families in all of the aquarium systems). Most viromes were dominated by DNA phages of the order Caudovirales as commonly found in other aquatic environments with average relative abundance greater than 64%. The composition and structure of aquarium viromes were associated with controlled system parameters, including nitrate, salinity, and temperature as well as resident animal profiles, indicating the close interaction of viromes with aquarium management practices. Furthermore, finding human associated viruses in a touch exhibit suggested that exposure of aquarium systems to human contact may lead to introduction of human cutaneous viruses into aquaria. This is consistent with the high abundance of skin microflora on the palms of healthy individuals and their detection in recreational waters, such as swimming pools. Lastly, assessment of antibiotic resistance genes (ARGs) in aquarium viromes revealed a unique signature of ARGs in different aquarium systems with trimethoprim being the most common. This is the first study to provide vital information on viromes and their unique relationships with management practices in a human-built and controlled aquarium environment

Time spent outdoors in childhood is associated with reduced risk of myopia as an adult

Myopia (near-sightedness) is an important public health issue. Spending more time outdoors can prevent myopia but the long-term association between this exposure and myopia has not been well characterised. We investigated the relationship between time spent outdoors in childhood, adolescence and young adulthood and risk of myopia in young adulthood. The Kidskin Young Adult Myopia Study (KYAMS) was a follow-up of the Kidskin Study, a sun exposure-intervention study of 1776 children aged 6–12 years. Myopia status was assessed in 303 (17.6%) KYAMS participants (aged 25–30 years) and several subjective and objective measures of time spent outdoors were collected in childhood (8–12 years) and adulthood. Index measures of total, childhood and recent time spent outdoors were developed using confirmatory factor analysis. Logistic regression was used to assess the association between a 0.1-unit change in the time outdoor indices and risk of myopia after adjusting for sex, education, outdoor occupation, parental myopia, parental education, ancestry and Kidskin Study intervention group. Spending more time outdoors during childhood was associated with reduced risk of myopia in young adulthood (multivariable odds ratio [OR] 0.82, 95% confidence interval [CI] 0.69, 0.98). Spending more time outdoors in later adolescence and young adulthood was associated with reduced risk of late-onset myopia (≥ 15 years of age, multivariable OR 0.79, 95% CI 0.64, 0.98). Spending more time outdoors in both childhood and adolescence was associated with less myopia in young adulthood

CD98hc facilitates B cell proliferation and adaptive humoral immunity.

The proliferation of antigen-specific lymphocytes and resulting clonal expansion are essential for adaptive immunity. We report here that B cell-specific deletion of the heavy chain of CD98 (CD98hc) resulted in lower antibody responses due to total suppression of B cell proliferation and subsequent plasma cell formation. Deletion of CD98hc did not impair early B cell activation but did inhibit later activation of the mitogen-activated protein kinase Erk1/2 and downregulation of the cell cycle inhibitor p27. Reconstitution of CD98hc-deficient B cells with CD98hc mutants showed that the integrin-binding domain of CD98hc was required for B cell proliferation but that the amino acid-transport function of CD98hc was dispensable for this. Thus, CD98hc supports integrin-dependent rapid proliferation of B cells. We propose that the advantage of adaptive immunity favored the appearance of CD98hc in vertebrates