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A growing number of biological studies suggest that exogenous sulfur dioxide (SO2) at a certain concentration may promote human resistance to Mycobacterium tuberculosis. However, the results of most relevant studies are inconsistent, and few studies have explored the relationship between SO2 exposure and tuberculosis risk at provincial level. In addition, occupational exposure has long been considered to have a certain impact on the human body, so for the first time, we discussed the differences between different occupations in the study on the relationship between air pollutant exposure and tuberculosis risk, and evaluated the impact of occupational exposure. This study aimed to explore the association between short-term SO2 exposure and the risk of outpatient visits to tuberculosis in Anhui province and 16 prefecture-level cities from 2015 to 2020. We used several models for multi-stage analysis, including distributed lag nonlinear model (DLNM), Poisson generalized linear regression model, and random-effects model. The association was assessed using the 28-day cumulative lag effect RR and 95%CI for each 10-unit increase in SO2 concentration. We divided all patients into the following six occupations: Worker, Farmer, Retired people, Children and Students, Cadre and Office clerk, and Service staff (catering, business, etc.). Sex, age, and season were analyzed by subgroup. Finally, the robustness of the multi-pollutant model was tested. At provincial level, the overall effect value of SO2 was RR=0.8191 (95%CI: 07702~0.8712); after grouping all patients by occupation, the association found only among Farmers (RR = 0.7150, 95%CI: 0.6699–0.7632, lag 0–28 days) and Workers (RR = 0.8566, 95%CI: 0.7930–0.9930, lag 0–4 days) was still statistically significant. Estimates for individual cities and using random-effects models to estimate average associations showed that SO2 exposure was associated with a reduced risk of outpatient TB visits in 14 municipalities, which remained significant when aggregated (RR = 0.9030, 95%CI: 0.8730–0.9340). Analysis of patients grouped by occupation in each municipality showed that statistical significance was again observed only in the Farmer (RR = 0.8880, 95%CI: 0.8610–0.9160) and Worker (RR = 0.8250, 95%CI: 0.7290–0.9340) groups. Stratified analysis of age, sex, and season showed that the effect of SO2 exposure was greater for middle-aged people (18–64 years old) and males, and less for seasonal changes. In summary, we found that exposure to SO2 reduces the risk of outpatient visits to tuberculosis, with farmers and workers more susceptible to SO2. Gender and age had a greater impact on the risk of TB outpatient visits than seasonal variations. [ABSTRACT FROM AUTHOR]

The Gd60Co30Fe10 alloy ribbons with different solidification cooling rates were prepared by modifying the melt-spinning speed of 6.0, 12.5, 25.0 and 50.0 m·s−1. With cooling rate decreasing, the (Fe,Co)5Gd and hcp-Gd nanocrystalline was in situ precipitated among the amorphous matrix, which resulted in the composition change of the amorphous phase. Because of the only slight amount of crystalline phase in Gd60Co30Fe10 alloys, the magnetic and magnetocaloric properties mainly depend on the amorphous phase, and all the magnetic entropy change versus temperature (|ΔSM|–T) curves are table-like, indicating the suitability for Ericsson cycle. The magnetic transition temperature of the Gd60Co30Fe10 alloy at a melt-spinning speed of 6.0 m·s−1 shifted obviously to the lower value with the applied magnetic fields increasing. The peak value of magnetic entropy change (|ΔSMpk|) is 2.19 J·kg−1·K−1 at 217 K under the magnetic field change of 0–2 T, and the table-like region is 200–230 K. It was proved that the moderate reduction of the cooling rate will not deteriorate the magnetocaloric performance of the Gd60Co30Fe10 ribbons seriously. 摘要: 使用熔体旋淬法, 通过调节辊轮转速为6.0, 12.5, 25.0 和 50.0 m·s−1, 制备了不同冷却速度的Gd60Co30Fe10合金条带。随着冷却速度的降低, (Fe,Co)5Gd和hcp-Gd纳米晶从非晶基体中原位析出, 使非晶相的成分发生变化。由于析出的晶相含量较低, 因此整个样品的磁性能和磁热性能主要取决于非晶相, 磁熵变温变 (|ΔSM|-T) 曲线均呈平台型, 表明其适用于Ericsson循环。辊轮转速为6.0 m·s−1时制备的Gd60Co30Fe10合金的磁转变温度随着外加磁场的增加明显向低温偏移, 在磁场变化为0-2 T的条件下, 217 K时磁熵变峰值 (|ΔSMpk|) 为2.19 J·kg−1·K−1, 平台区为200-230 K。本研究证明适度的降低冷却速度, 不会使Gd60Co30Fe10合金条带的磁热性能表现严重恶化。 [ABSTRACT FROM AUTHOR]