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To explore the effects of occupational aluminum exposure on workers’ cognitive function and blood glucose concentration, and to analyze whether blood glucose concentration can mediate the cognitive changes caused by aluminum.

With the expansion of the power grid scale and the enhancement of network structure interconnection, the short-circuit current of power grids is increasingly close to the upper capacity limit of circuit breakers. The fault current limiter is effective in suppressing the short-circuit current of power grids, and with the mature development of superconducting technology, high-temperature superconducting fault current limiters (HTS-FCLs) have been widely used in power grids. Due to the nonlinear impedance–current characteristic of HTS-FCLs, the traditional short-circuit current calculation method is inapplicable to power grids with HTS-FCLs. First, based on the establishment of the electromechanical transient model and the short-circuit calculation model, the short-circuit current calculation procedure for power grids with HTS-FCLs is proposed. Second, the calculation methods for three-phase and single-phase short-circuit currents at the substation bus in power grids with HTS-FCLs are analyzed. Finally, three-phase and single-phase short-circuit currents at the 500 kV Xijiang substation bus in the Guangdong power grid are calculated as the study case. Simulation results show that compared with the situation where there is no HTS-FCL installed, the short-circuit current on the 500 kV bus decreases from 65.34 to 58.31 kA in terms of the three-phase short-circuit fault, and decreases from 54.56 to 46.62 kA in terms of the single-phase short-circuit fault, thus verifying the effectiveness and practicability of HTS-FCLs in suppressing the short-circuit current, which is significant for the safe, stable and reliable operation of the power grid.

Carbon emissions at the provincial level are mostly calculated based on production responsibility, which ignores the carbon emission accounting perspectives of consumption and income responsibility. However, scientific accounting of carbon emissions from multiple perspectives is crucial to equitably distribute the responsibilities for reducing emissions. This study utilises an input‒output model for multi-regional carbon emissions to calculate carbon emissions from production-, consumption- and income-based perspectives for exploring the variability in the responsibilities for reducing emissions at the provincial level. The Tapio decoupling coefficient is used to analyse the relationship between carbon emissions and economic growth in key provinces, and the Logarithmic Mean Divisia Index (LMDI) model is used to determine the factors promoting or inhibiting the decoupling of carbon emissions under different responsibility perspectives. The results show that, firstly, the national carbon emissions illustrate the following trend: production-based emissions > income-based emissions > consumption-based emissions. Secondly, provinces in strong decoupling states are distributed in a northeast–southwest direction. Carbon emissions and decoupling situations differ among varying responsibility perspectives due to interprovincial transfers of carbon emissions. Thus, a compensation mechanism should be established to promote a fair and orderly peaking in each province. Lastly, carbon emission intensity is a factor promoting decoupling in all three perspectives. In the meantime, output scale, economic development and factor input are the major inhibiting factors for the decoupling of production-, consumption- and income-based emissions, respectively.

Smart hydrogel is a kind of new soft and wet material which can be responsive to external stimuli. Hydrogel fiber owning one dimension size can significantly improve response speed and be easily formed into higher-order assemblies. N-isopropylacrylamide/calcium alginate (NIPA/Ca-alginate) as-spun fiber was generated via microfluidic spinning. Then PNIPA/Ca-alginate hydrogel fiber was prepared through off-chip free radical polymerization of NIPA in the presence of Ca-alginate. The structure and morphology of the hydrogel fiber were characterized by FTIR and SEM. The swelling property and temperature-/pH-response behaviors were also investigated. The PNIPA/Ca-alginate hydrogel fiber had a 3D network porous structure. The thinner the hydrogel fiber, the faster the swelling speed was. Meanwhile, the hydrogel fiber exhibited temperature and pH response.

To compare the therapeutic effects of two different moxibustion methods both with tai-yi moxa stick in treating primary dysmenorrhea. Forty-three patients were randomized into two groups by the random number table according to their treatment orders. The causalgic group was intervened by causalgic stimulation with tai-yi moxa stick while the tepid group was treated by mild thermal stimulation with tai-yi moxa stick. Shiqizhui (EX-B 8) was selected for both groups. Visual analogue scale (VAS) was used for observation before and during the treatment by every 10 min to compare the clinical efficacies between the two groups. Before treatment, there was no statistically significant difference in pain intensity between the two groups (P>0.05). After treatment, both groups achieved significant improvements in pain intensity (P< 0.05), but the inter-group difference in pain intensity was still statistically insignificant (P> 0.05), but the difference was enlarged comparing with that before treatment. The pain relief during the first 10 min of treatment was slower in the causalgic group than that in the tepid group. However, during the later 20 min, the pain relief in the calsalgia group gradually outpaced that in the tepid group. The two moxibustion methods with tai-yi moxa stick both have a good instant analgesic effect in treating primary dysmenorrhea. For patients with primary dysmenorrhea, if 30 min is regarded as the treatment time, mild stimulation was suggested to be used for the first 10 min, and causalgic stimulation for the later 20 min to achieve a better curative effect.

With the enlarging scale of power grids, the quantity of electric equipments is increasing and their quality is improving. Therefore, the optimizing management of equipments, which is an important act to reduce investment and increase economic benefit of power grids, has been paid more and more attention. This paper makes a comprehensive analysis of factors that influence the life cycle cost of electric equipments. Considering the risk of power grid caused by the fault of equipments and other relevant factors, the economic life model is established and the judgment about the optimal maintenance strategy is proposed. The proposed maintenance strategy is conducive to save the operating cost of power grids and optimize the investment. Also, it can promote the refined management and provide reference decisions for electric utilities to plan and adjust equipments operating better.