Odds and ends of atmospheric mercury in Europe and over the North Atlantic Ocean: temporal trends of 25 years of measurements

The global monitoring plan of the Minamata Convention on Mercury was established to generate long-term data necessary for evaluating the effectiveness of regulatory measures at a global scale. After 25 years of monitoring (since 1995), Mace Head is one of the atmospheric monitoring stations with the longest mercury record and has produced sufficient data for the analysis of temporal trends of total gaseous mercury (TGM) in Europe and the North Atlantic. Using concentration-weighted trajectories for atmospheric mercury measured at Mace Head as well as another five locations in Europe, Amderma, Andoya, Villum, Waldhof and Zeppelin, we identify the regional probabilistic source contribution factor and its changes for the period of 1996 to 2019. Temporal trends indicate that concentrations of mercury in the atmosphere in Europe and the North Atlantic have declined significantly over the past 25 years at a non-monotonic rate averaging 0.03 ng m(-3) yr(-1). Concentrations of TGM at remote marine sites were shown to be affected by continental long-range transport, and evaluation of reanalysis back trajectories displays a significant decrease in TGM in continental air masses from Europe in the last 2 decades. In addition, using the relationship between mercury and other atmospheric trace gases that could serve as a source signature, we perform factorization regression analysis, based on positive rotatable factorization to solve probabilistic mass functions. We reconstructed atmospheric mercury concentration and assessed the contribution of the major natural and anthropogenic sources. The results reveal that the observed downward trend in the atmospheric mercury is mainly associated with a factor with a high load of long-lived anthropogenic species

Safety and efficacy of an attenuated heartwater (Ehrlichia ruminantium) vaccine administered by the intramuscular route in cattle, sheep and Angora goats

Please read abstract in the article.Red Meat Research and Development Trust of South Africa; Mohair South Africa LTD; Technology Innovation Agency, South Africa; Agricultural Research Council, South Africa.http://www.elsevier.com/locate/vaccinehj2021Veterinary Tropical Disease

Molecular Typing of Treponema pallidum: A Systematic Review and Meta-Analysis

Syphilis has been resurgent in many parts of the world in past decades. Understanding the epidemiology of syphilis is important for estimating disease burdens, monitoring epidemic trends, and evaluating intervention activities. Treponema pallidum (T. pallidum), the pathogen of syphilis, cannot be grown in vitro. Because T. pallidum cannot be cultured, molecular typing of T. pallidum is particularly useful and allows for investigation of infection diversity and epidemiology. We conducted a statistical analysis of available published data to investigate the current research progress of molecular typing of syphilis. Our analysis showed that primary lesion was a better specimen for obtaining T. pallidum DNA than blood. Blood specimens collected from scraping the ear lobes had high yield of T. pallidum DNA and high full typing efficiency. Ear lobe blood is a promising specimen for future T. pallidum molecular typing, but further research should verify this finding using a larger sample size. Within all studies, subtype 14d was most prevalent, and subtype distribution varied across geographic areas. Subtype data associated with macrolide resistance and neurosyphilis were limited. More research on molecular typing of T. pallidum can be useful for investigating syphilis epidemiology and designing syphilis control strategies

Towards a conceptual framework for communicating library training to students in South African university libraries: A literature review

Developing conceptual frameworks to improve library training among librarians in South African university libraries is not common. The purpose of this article was to assess, synthesise and critique available literature to determine the extent to which librarians in South African university libraries could reflect on their library training and synthesise relevant theories and models that can assist develop a conceptual framework for communicating library training. The integrated literature review focuses on five central themes namely: communication models, the evolution of technology, learning theories, social learning and web based learning environments, and the role of authority in teacher-learner relationships. The article argues that academic librarians operate within the universe of teacher-learner relationships in library training initiatives, albeit unconsciously so. This makes library training in South African university libraries a mature topic needing reconceptualization. Future research should employ single and multiple case study research designs to formulate frameworks on a case-by-case basis

Cisplatain Induced Changes in Murine Renal Cortex and Medulla: Proc.Amer.Assoc.Cancer Res.

NRC publication: Ye