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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]

In this work, the acylamino group has been introduced into energetic materials to build acylamino-bridged bis(1,2,4-triazole) 3 and its nitration derivative 4. Both 3 and 4 were thoroughly characterized via spectroscopic and structural methods. In addition, their sensitivities toward friction and impact were determined and the energetic performances of 3 and 4 were calculated using the EXPLO5 code. Compound 3 is insensitive to mechanical stimulation (IS: 40 J, FS: 320 N). Besides, compared with the C–C-bonded compound DNABT (IS: 3 J, D: 8355 m s−1) without any bridging group, 4 achieves a balance between the sensitivity (IS: 18 J, FS: 200 N) and the detonation velocity (D: 8564 m s−1). The effect of introducing an acylamino group into 3 and 4 was elucidated using HOMO–LUMO analysis and the anisotropy of the induced current-density method. [ABSTRACT FROM AUTHOR]

Abstract In recent years, nickel oxide has attracted much attention for the supercapacitor application because of the advantages of low toxicity, cheapness and environment friendliness. This review focuses on the performance of nickel oxide and its composites in supercapacitors and their synthesizing strategies. It is concluded that the supercapacitor performance depends on morphologies, surface area, particle size, porosity and crystallinity of nickel oxide materials. Their three-dimensional morphology with porous structures usually presents higher specific capacitance. Compared with pure NiO nanocrystals, NiO-based composites often show higher specific capacitance resulting from the synergetic effects between the components. Furthermore, the strategies for preparing NiO-based materials including hydrothermal/solvothermal methods, electrospinning technique and microwave-assisted method, and the factors affecting their electrochemical performance have also been summarized. [ABSTRACT FROM AUTHOR]

• The diamond-indent feature of MSF provides favorable interfacial bond strength. • MSF can compensate for the reduction in compressive strength caused by IOTs. • The fracture energy of IOT concrete increases by up to 20.19-fold due to MSF. • The relationship between the FRI and post-cracking behavior is developed. Iron ore tailing (IOT) is a hazardous by-product of iron extraction, and its disposal has resulted in serious environmental issues. This paper investigated the interfacial bond performance of macro-synthetic fiber (MSF). The effect of the IOT replacement ratio on the compressive performance of concrete and the effects of MSF on the compressive and flexural performance of IOT concrete were evaluated. Test parameters included IOT replacement ratio (0%, 50% and 100%), fiber volume fraction (0%, 0.5%, 1.0%, 1.5% and 2%) and fiber aspect ratio (43, 60 and 69). The test results indicated that the deterioration in compressive strength was observed with the increase in the IOT replacement ratio. The mechanism of the effect of IOT on the compressive performance of concrete was analyzed. However, the incorporation of MSF compensated for the reduction in compressive strength caused by iron ore tailings (IOTs). Furthermore, the post-cracking performance, which includes residual flexural tensile strength, equivalent flexural tensile strength and fracture energy, of concrete increased with the increase in fiber volume fraction. The fracture energy of IOT concrete increased by a factor of 18.06–20.19, and the post-cracking performance of IOT concrete was comparable with that of natural sand (NS) concrete at an MSF fiber volume fraction of 2%. At a given fiber volume fraction, the MSF with a higher fiber aspect ratio was more effective in improving post-cracking performance than one with a lower aspect ratio. Moreover, new empirical equations were proposed, which can accurately predict the residual flexural tensile strengths and equivalent flexural tensile strengths. These results provide important implications for determining the contribution of MSF in strengthening and toughening IOT concrete. [ABSTRACT FROM AUTHOR]

• The material characteristics of IOT are summarized. • The properties of IOT concrete are analyzed and compared with those of NS concrete. • IOT concrete has satisfactory workability, mechanical properties and durability. • The relationships between the mechanical properties of IOT concrete are established. • The application of IOT into concrete achieves sustainable development. Incorporating waste by-products in concrete is one of the critical approaches for sustainable development. Particularly, iron ore tailings (IOT) as ordinary industrial solid waste in China is discharged and deposited. This review is a recapitulation of the material characteristics of IOT and its effects on the workability, mechanical properties, and durability of concrete. The increasing development of ore beneficiation technology, along with the collection from various sources, results in the diversity of IOT characteristics. Owing to low pozzolanic activity, IOT is generally limited to substitute cement in concrete, so which need to be activated when partly replacing cement. Moreover, their high specific surface area and irregular shape have a detrimental effect on the workability of concrete; however, mechanical properties and durability exhibit different trends with increasing replacement of IOT in concrete. And we find that on the status of an appropriate replacement IOT can lead to a satisfactory workability, mechanical properties and durability of concrete. Based on previous research, we establish the fundamental correlation between mechanical properties. These conclusions can guide the application of IOT in concrete sustainable technology. [ABSTRACT FROM AUTHOR]

The performance gap of buildings is commonly defined as the difference between the performance value predicted in the design stage and that measured in the post-occupancy stage. Knowledge about the performance gap of buildings is valuable in many aspects and thus is a research subject drawing much attention. Important questions that should be asked include: (1) Definition: what is the performance gap of buildings? (2) Magnitude: how large is the performance gap of buildings? (3) Techniques: how to determine the performance gap of buildings? (4) Causes: what are the reasons leading to the performance gap of buildings? (5) Solutions: how to bridge the performance gap of buildings. By collecting and analyzing more than 20 published works with reported data on the performance gap of buildings and other research articles, these important questions are addressed. Through this review state-of-the-art knowledge regarding the performance gap of buildings is presented. Major conclusions are drawn and future research directions are pointed out. [ABSTRACT FROM AUTHOR]

Hydatid disease imposing serious threat on human health and great loss in live¬stock pastoralism remains a major public health problem in western China. To assess and monitor the effect of control program on transmission dynamics, we used the prevalence of cystic echinococcosis in slaughtered sheep at slaughterhouse as an indicator during the period of 2007 to 2013 in Emin County, Xinjiang Uygur Autonomous Region, China. The results showed a significant decline trend of prevalence in all age groups during the 7 years when the control program was implemented; particularly, the rate was reduced by 72% after first 3 years. Among the sheep slaughtered, the age distribution evidenced that the prevalence increased significantly as the sheep grew older. The baseline data indicated that the rate was 4.5% at the age <1, 6.7% at age 2~, and reached to the highest 17.9% at age ≥ 4 years. Earlier response to the intervention pressure was seen in the sheep at the younger age. Significant decline started from 2008 at the age <1, from 2009 at age of 1~, 2010 at 2~ to 3~, and the latest, in 2012 at age ≥ 4. This study demonstrated that the prevalence of cystic echinococcosis in slaughtered sheep may be used as an indicator to assess and monitor the transmission status during and after control program providing information for betterment of performance to sustain control strength.