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BackgroundIn 2013, a tuberculosis (TB) outbreak occurred in a middle school in Henan province of China. An outbreak survey was carried out in the school.ObjectivesThis study was undertaken to investigate the detection rate of TB cases and those with strong Mantoux positive (SMP), defined as tuberculin skin test (TST) indurations of 15mm or larger and/or blisters, necrosis or lymphangitis, and to identify their risk factors.MethodsThe TST, chest x-ray/radiography, and TB-suspicious symptoms interview were used to screen for TB cases. Their diagnosis was made by sputum smear microscopy, liquid culture, computed tomography (CT), and diagnostic therapy if necessary. We retrospectively analyzed the outbreak survey data of 4082 students and 278 staff in the school. Logistic regression models were used to identify the risk factors associated with SMP and TB disease.ResultsApproximately 3.55% of students and 16.55% of staff were SMP. SMP rate in students was significantly lower than that in staff (p

The Cu–Cr–Ni alloy is a key material for the manufacturing of connectors, which requires excellent resistance to stress relaxation. However, the inherent correlation among microstructure, texture, and properties is still unclear. In this study, we investigated the influence of calefaction and stress relaxation on the grain boundaries (GBs), textures, and properties of the Cu–Cr–Ni alloy. The results showed that calefaction and stress relaxation had opposite effects on GBs and textures. Calefaction led to a decrease in the proportion of low-angle grain boundaries (LAGBs), an increase in the Schmidt factor (SF) value of the grains, and a transition of texture from <111> to <113>. The grains with higher SF values were more susceptible to plastic deformation, which deteriorated the stress relaxation resistance. By comparison, stress relaxation led to an increase in the proportion of LAGBs, a decrease in SF values of the grains, and a transition of texture from <113> to <111> and <001>. After stress relaxation, the variation trends of the GBs and textures were consistent with those of other plastic deformations, indicating that stress relaxation can be verified by the variations in GBs and textures. Our findings provide a theoretical basis for improvements in stress relaxation resistance of the Cu-based alloys used in connector industry. [ABSTRACT FROM AUTHOR]

Copper alloys used in connectors rely significantly on stress relaxation resistance as a key property. In this study, a heavily deformed Cu-Cr-Ag-Si alloy underwent aging at varying temperatures, with a subsequent analysis of its mechanical properties and microstructure, with a particular emphasis on understanding the mechanism of improving stress relaxation resistance. As the aging temperature rose, the Cr precipitated into a Cr-Si composite element precipitated phase. Both work hardening and precipitation strengthening played vital roles in enhancing the stress relaxation resistance of the Cu-Cr-Ag-Si alloy, with the latter exerting a more pronounced impact. The notable performance enhancement observed after aging at 450 °C can be attributed to the synergistic effects of work hardening and precipitation strengthening. Following aging at 450 °C, the alloy demonstrated optimal performance, boasting a tensile strength of 495.25 MPa, an electrical conductivity of 84.2% IACS, and a level of 91.12%. These exceptional properties position the alloy as a highly suitable material for connector contacts. [ABSTRACT FROM AUTHOR]

Aedes sp. mosquitoes are changing their geographic range in response to climate change. This is of concern because these mosquitoes can carry dengue fever and other viral diseases. Changing weather patterns can also increase the numbers of Aedes mosquitoes, leading to greater human exposure and enhancing population health risks. We project the geographic distribution of Aedes and associated changes in populations exposed to dengue in Asian metropolitan areas under warming scenarios from 1.5°C to 5.0°C above pre‐industrial temperatures, using multi‐model ensembles. With global warming, the southern part of the Arabian Peninsula, the coast of the Arabian Sea in southern Iran, southern Pakistan in West Asia, the Korean Peninsula, most of the Japanese islands, and parts of North China in East Asia are projected to become suitable for dengue transmission. The numbers of metropolitan areas exposed to dengue is projected to change from 142 (48%) in the reference period (1995–2014) to 211 (71%) at 5.0°C warming. With the combined impact of socioeconomic and climate change, population exposure to dengue in Asian metropolitan areas is projected to increase from 263 (multi‐model range 252–268) million in 1995–2014 to 411 (394–432) million, 446 (420–490) million, 509 (475–601), 558 (493–685) and 587 (529–773) million, respectively, at 1.5°C, 2.0°C, 3.0°C, 4.0°C and 5°C warming, with an average of 2.9 million new people exposed to dengue fever in metropolitan areas each year. Plain Language Summary: Dengue fever, spread by Aedes aegypti and Aedes albopictus mosquitoes, is the most serious arbovirus disease affecting Asia. With global warming, mosquitoes that may carry dengue virus continue to expand in geographic range and vectorial capacity. Continued growth of mosquito populations can lead to a considerable increase in dengue exposure, especially in urban areas, increasing public health risks. Based on the occurrence data of the two mosquito species and climate observations, we explored the correlation between different climate elements and the spread of the mosquitoes. Using the outputs of 34 global climate models, we project the probability of occurrence and mosquito vectorial capacity under different warming levels in Asia. With global warming, much of Asia's area is projected to become suitable for dengue transmission. We have also estimated the future population changes in Asian metropolitan areas, to explore the combined effects of socioeconomy and climate change on exposure to dengue. As population density continues to increase and dengue epidemic potential rises, the population exposed to potential dengue fever transmission in Asian metropolitan areas is projected to surge in the future. Information conveyed in our paper can help increase preparedness for dengue outbreaks. Key Points: With global warming, a large number of areas in Asia are projected to become emerging regions suitable for dengue transmissionThe combined effects of climate and socioeconomic changes are projected to jointly lead to a surge in the population exposed to dengueAn average of 2.9 million new people are projected to be exposed to dengue fever in metropolitan areas each year in the future [ABSTRACT FROM AUTHOR]

The evidence remains inconsistent regarding whether vitamin D deficiency (VDD) increases the risk of prediabetes. This study aimed to examine whether there is sex-specific association between VDD and impaired fasting glucose (IFG) or impaired glucose tolerance (IGT) in Henan. The data were sourced from the survey of chronic diseases and nutrition in Henan. Multinomial logistic regression models based on complex sampling design and weight were developed to estimate the odds ratio (OR) and confidence interval (95%CI) for measuring the association between VDD and IFG/IGT. The prevalence rate of IGT in men was 20.1% in the VDD group, significantly higher than that in the non-VDD group (10.5%), but no significant difference was observed in women between the VDD and non-VDD groups; there were no significant differences in IFG prevalence between the VDD and non-VDD groups in either men or women. It was found that the association between VDD and IGT was statistically significant in men. The adjusted OR (95%CI) of VDD was 1.99 (1.24–3.19) for IGT in men and 14.84 (4.14–53.20) for IGT in men having a family history of DM. Thus, men with VDD were more likely to live with IGT than those without VDD, especially for men having a family history of diabetes. [ABSTRACT FROM AUTHOR]