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Background: Human cystic and alveolar echinococcosis are neglected tropical diseases that WHO has prioritized for control in recent years. Both diseases impose substantial burdens on public health and the socio-economy in China. In this study, which is based on the national echinococcosis survey from 2012 to 2016, we aim to describe the spatial prevalence and demographic characteristics of cystic and alveolar echinococcosis infections in humans and assess the impact of environmental, biological and social factors on both types of the disease. Methods: We computed the sex-, age group-, occupation- and education level-specific prevalences of cystic and alveolar echinococcosis at national and sub-national levels. We mapped the geographical distribution of echinococcosis prevalence at the province, city and county levels. Finally, by analyzing the county-level echinococcosis cases combined with a range of associated environmental, biological and social factors, we identified and quantified the potential risk factors for echinococcosis using a generalized linear model. Results: A total of 1,150,723 residents were selected and included in the national echinococcosis survey between 2012 and 2016, of whom 4161 and 1055 tested positive for cystic and alveolar echinococcosis, respectively. Female gender, older age, occupation at herdsman, occupation as religious worker and illiteracy were identified as risk factors for both types of echinococcosis. The prevalence of echinococcosis was found to vary geographically, with areas of high endemicity observed in the Tibetan Plateau region. Cystic echinococcosis prevalence was positively correlated with cattle density, cattle prevalence, dog density, dog prevalence, number of livestock slaughtered, elevation and grass area, and negatively associated with temperature and gross domestic product (GDP). Alveolar echinococcosis prevalence was positively correlated with precipitation, level of awareness, elevation, rodent density and rodent prevalence, and negatively correlated with forest area, temperature and GDP. Our results also implied that drinking water sources are significantly associated with both diseases. Conclusions: The results of this study provide a comprehensive understanding of geographical patterns, demographic characteristics and risk factors of cystic and alveolar echinococcosis in China. This important information will contribute towards developing targeted prevention measures and controlling diseases from the public health perspective. [ABSTRACT FROM AUTHOR]

Pincer ligand supported RuII chloride complexes may be used for acetylene hydrochlorination as non-mercury molecular catalysts. Based on theoretical calculations, the catalytic mechanism and the interaction between catalysts and reactants has been evaluated, indicating that the (pincer)RuIICl2 platform supports electrophilic proton-ruthenation of C2H2. Energy decomposition studies further illustrate the electron-rich property of the RuII center, which can increase the negative charge of C2H2 via 4d-electron backdonation. Thus, the electrophilic reaction mechanism is favored due to lower energetic barriers. By improving the electron-donating ability of ligands, this lowering of energetic barriers can be enhanced. Therefore, non-mercury catalysts for acetylene hydrochlorination with milder reaction conditions and higher catalytic activity can be designed. [ABSTRACT FROM AUTHOR]

Macro‐synthetic fiber‐reinforced iron ore tailings (IOT) concrete is an environment‐friendly building material featured by recycling IOT and improving performance of IOT concrete due to fiber incorporation. In this study, the mechanical properties of macro‐synthetic fiber‐reinforced concrete incorporating IOT were investigated. Two different replacement ratios of IOT (i.e., 0% and 50%) and six types of macro‐synthetic fibers at 1.0 vol% were adopted to investigate the effects of IOT, aspect ratio, elastic modulus, and tensile strength of macro‐synthetic fibers on mechanical properties of concrete. The results indicate that the concrete with IOT for natural sand (NS) replacement in 50 wt% demonstrates no loss in compressive strength and a minor loss of 7.67% in fracture energy, but the incorporation of IOT lowers splitting tensile strength and limit of proportionality, especially the splitting tensile strength with a decrease of 18.50%. The splitting tensile strength, equivalent flexural tensile strength, residual flexural tensile strength, and fracture energy were notably improved by adding macro‐synthetic fibers. Experimental results using Tukey test and Student's t test demonstrated that the fiber aspect ratio was more effective in improving equivalent flexural tensile strength, residual flexural tensile strength, and fracture energy than the elastic modulus and tensile strength of fibers, and the residual flexural tensile strength fR,4 was enhanced by 146.34% when increasing the fiber aspect ratio from 36 to 60. [ABSTRACT FROM AUTHOR]