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Summary: Background: Short-term exposure to particulate matter air pollution has been associated with the exacerbations of COPD, but its association with COPD mortality was not fully elucidated. We aimed to assess the association between short-term particulate matter exposure and the risk of COPD mortality in China using individual-level data. Methods: We derived 2.26 million COPD deaths from a national death registry database in Chinese mainland between 2013 and 2019. Exposures to fine particulate matter (PM2.5) and coarse particulate matter (PM2.5-10) were assessed by satellite-based models of a 1 × 1 km resolution and assigned to each individual based on residential address. The associations of PM2.5 and PM2.5-10 with COPD mortality were examined using a time-stratified case-crossover design and conditional logistic regressions with distributed lag models. We further conducted stratified analyses by age, sex, education level, and season. Findings: Short-term exposures to both PM2.5 and PM2.5-10 were associated with increased risks of COPD mortality. These associations appeared and peaked on the concurrent day, attenuated and became nonsignificant after 5 or 7 days, respectively. The exposure-response curves were approximately linear without discernible thresholds. An interquartile range increase in PM2.5 and PM2.5-10 concentrations was associated with 4.23% (95% CI: 3.75%, 4.72%) and 2.67% (95% CI: 2.18%, 3.16%) higher risks of COPD mortality over lag 0–7 d, respectively. The associations of PM2.5 and PM2.5-10 attenuated slightly but were still significant in the mutual-adjustment models. A larger association of PM2.5-10 was observed in the warm season. Interpretation: This individual-level, nationwide, case-crossover study suggests that short-term exposure to PM2.5 and PM2.5-10 might act as one of the environmental risk factors for COPD mortality. Funding: This study is supported by the National Key Research and Development Program of China (2023YFC3708304 and 2022YFC3702701), the National Natural Science Foundation of China (82304090 and 82030103), the 3-year Action Plan for Strengthening the Construction of the Public Health System in Shanghai (GWVI-11.2-YQ31), and the Science and Technology Commission of Shanghai Municipality (21TQ015).

Line commutated converter based high voltage direct current (LCC-HVDC) is the key to large-scale grid connection and long-distance transmission of renewable energy. However, faults such as DC blocking and commutation failure may lead to short-term excess reactive power and transient overvoltage at the sending end, endangering operational safety. In this paper, a method based on grid-forming based reactive power compensation device (GFM-RPC) to suppress transient overvoltage at the renewable energy transmission terminal is proposed, which is different from the traditional reactive power compensation with the characteristic of current source based on voltage-current cascade control. A voltage dynamic analysis model based on differential-algebraic relationship is constructed to clarify the mechanism of GFM-RPC suppressing transient overvoltage, and the advantages of the proposed method compared to existing methods based on static synchronous compensator (STATCOM) for suppressing transient overvoltage is compared and analyzed. The simulation is used to verify the effect of GFM-RPC on the suppression of transient overvoltage at the renewable energy transmission terminal, and the influence of the main parameters on the overvoltage suppression effect is analyzed. It is shown that reactive power compensation devices such as STATCOM with external characteristics of current sources exhibit a reverse regulation characteristic of deteriorating voltage dynamics at the moment of DC transmission system fault, while the reverse regulation characteristic can be eliminated by GFM-RPC, as well as suppression of voltage magnitude overshoot can be achieved through reasonable parameter configuration for GFM-RPC.

Background and objectives: Many studies suggested that short-term exposure to fine particulate matter (PM2.5) and coarse particulate matter (PM2.5–10) was linked to elevated risk of cerebrovascular disease. However, little is known about the potentially differential effects of PM2.5 and PM2.5–10 on various types of cerebrovascular disease. Methods: We collected individual cerebrovascular death records for all residents in Shanghai, China from 2005 to 2021. Residential daily air pollution data were predicted from a satellite model. The associations between particulate matters (PM) and cerebrovascular mortality were investigated by an individual-level, time-stratified, case-crossover design. The data was analyzed by the conditional logistic regression combined with the distributed lag model with a maximum lag of 7 days. Furthermore, we explored the effect modifications by sex, age and season. Results: A total of 388,823 cerebrovascular deaths were included. Monotonous increases were observed for mortality of all cerebrovascular diseases except for hemorrhagic stroke. A 10 μg/m3 rise in PM2.5 was related to rises of 1.35% [95% confidence interval (CI): 1.04%, 1.66%] in mortality of all cerebrovascular diseases, 1.84% (95% CI: 1.25%, 2.44%) in ischemic stroke, 1.53% (95% CI: 1.07%, 1.99%) in cerebrovascular sequelae and 1.56% (95% CI: 1.08%, 2.05%) in ischemic stroke sequelae. The excess risk estimates per each 10 μg/m3 rise in PM2.5–10 were 1.47% (95% CI: 1.10%, 1.84%), 1.53% (95% CI: 0.83%, 2.24%), 1.93% (95% CI: 1.38%, 2.49%) and 2.22% (95% CI: 1.64%, 2.81%), respectively. The associations of both pollutants with all cerebrovascular outcomes were robust after controlling for co-pollutants. The associations were greater in females, individuals > 80 years, and during the warm season. Conclusions: Short-term exposures to both PM2.5 and PM2.5–10 may independently increase the mortality risk of cerebrovascular diseases, particularly of ischemic stroke and stroke sequelae.

The spatial disparity of air pollutants is one of the key influential factors for environmental inequality. We quantitatively evaluated the evolution of PM2.5 spatial disparity in China during 2013–2020, and investigated the associations between PM2.5 spatial disparity and economic indicators. Differences in PM2.5 between more- and less-polluted cities declined over time, suggesting decreased absolute disparity. However, the more polluted cities in 2013 remained so in 2017 and 2020, and vice versa, indicating persistent relative disparity. PM2.5 pollution levels increased with higher GDP per capita in less-developed areas of China, but such negative effects weakened over time, while economic development tended to promote cleaner air in developed areas of China. Therefore, policies to improve air quality and promote economic development simultaneously are needed in China to reduce the disparity of air pollution and promote all people to enjoy environmental equality.

Limited studies investigated the effects of long-term ozone exposure on cardiometabolic health. We aimed to examine the association of long-term ozone exposure with a range of cardiometabolic diseases, as well as the subclinical indicators in Eastern China. The study included 202,042 adults living in 11 prefecture-level areas in Zhejiang Province between 2014 and 2021. Using a satellite-based model with a 1 × 1 km spatial resolution, we estimated residential 5-year average ozone exposures for each subject. Mixed-effects logistic and linear regression models were applied to explore the associations of ozone exposure with cardiometabolic diseases and subclinical indicators, respectively. We found that a 9% [95% confidence interval (95% CI): 7–12%] higher in odds of cardiometabolic disease per 10 μg/m3 increase in ozone exposure. Specifically, we also found higher prevalence of cardiovascular diseases (15%), stroke (19%), hypertension (7%), dyslipidemia (15%), and hypertriglyceridemia (9%) associated with ozone exposure. However, we did not find significant associations between ozone exposure and coronary heart disease, myocardial infarction, or diabetes mellitus. Long-term ozone exposures were also significantly associated with adverse changes in systolic blood pressure, diastolic blood pressure, total serum cholesterol, triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, glucose concentration, and body mass index. Our results showed that people with lower education levels, those over 50 years old, and those who were overweight or obese were more susceptible to the effects of ozone on cardiometabolic diseases. Our findings demonstrated the detrimental effects of long-term ozone exposure on cardiometabolic health, emphasizing the need for ozone control strategies to reduce the burden of cardiometabolic diseases.

Background: A large gap exists between the latest Global Air Quality Guidelines (AQG 2021) and Chinese air quality standards for NO2. Assessing whether and to what extent air quality standards for NO2 should be tightened in China requires a comprehensive understanding of the spatiotemporal characteristics of population exposure to ambient NO2 and related health risks, which have not been studied to date. Objective: We predicted ground NO2 concentrations with high resolution in mainland China, explored exposure characteristics to NO2 pollution, and assessed the mortality burden attributable to NO2 exposure. Methods: Daily NO2 concentrations in 2019 were predicted at 1-km spatial resolution in mainland China using random forest models incorporating multiple predictors. From these high-resolution predictions, we explored the spatiotemporal distribution of NO2, population and area percentages with NO2 exposure exceeding criterion levels, and premature deaths attributable to long- and short-term NO2 exposure in China. Results: The cross-validation R2 and root mean squared error of the NO2 predicting model were 0.80 and 7.78 μg/m3, respectively, at the daily level in 2019. The percentage of people (population number) with annual NO2 exposure over 40 μg/m3 in mainland China in 2019 was 10.40 % (145,605,200), and it reached 99.68 % (1,395,569,840) with the AQG guideline value of 10 μg/m3. NO2 levels and population exposure risk were elevated in urban areas than in rural. Long- and short-term exposures to NO2 were associated with 285,036 and 121,263 non-accidental deaths, respectively, in China in 2019. Tightening standards in steps gradually would increase the potential health benefit. Conclusion: In China, NO2 pollution is associated with significant mortality burden. Spatial disparities exist in NO2 pollution and exposure risks. China’s current air quality standards may no longer objectively reflect the severity of NO2 pollution and exposure risk. Tightening the national standards for NO2 is needed and will lead to significant health benefits.

Background: Exposure to particulate matter (PM) has been a major public health threat, but the potentially differential effects on asthma of PM remain largely unknown in high altitude settings. We evaluated the effects of ambient PM on asthma in high altitude settings. Methods: The study recruited a representative sample from high altitude settings using a multistage stratified sampling procedure. Asthma was defined by a self-reported history of diagnosis by a physician or by wheezing symptoms in the preceding 12 months. The annual mean PM2.5 and PM10 concentrations were calculated for each grid cell at 1-km spatial resolution based on the geographical coordinates. Results: We analyzed data for participants (mean age 39.1 years, 51.4% female) and 183 (3.7%, 95% confidence interval (CI): 3.2–4.2) of the participants had asthma. Prevalence was higher in women (4.3%, 95% CI 3.5–5.1) than in men (3.1%, 2.4–3.8) and increasing with higher concentration of PM exposures. For an interquartile range (IQR) difference (8.77 μg/m3) in PM2.5 exposure, the adjusted odds ratio (OR) was 1.64 (95% CI 1.46–1.83, P

Recent evidence advises particles with a diameter of 2.5 µm or less (PM2.5) might be a prognostic factor for ovarian cancer (OC) survival. The oxidative balance score (OBS) incorporates diet-lifestyle factors to estimate individuals’ anti-oxidant exposure status which may be relevant to cancer prognosis. We aimed to investigate the roles of PM2.5, and OBS and their interaction in OC prognosis. 663 patients with OC were enrolled in the current study. Satellite-derived annual average exposures to PM2.5 based on patients’ residential locations. The OBS was calculated based on 16 different diet-lifestyle components derived using an acknowledged self-reported questionnaire. The Cox regression model was performed to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for overall survival (OS). We also assessed the effect of modification between PM2.5 and OS by OBS via interaction terms. During a median follow-up of 37.57 (interquartile:35.27–40.17) months, 123 patients died. Compared to low-concentration PM2.5 exposure, high PM2.5 during 1 year before diagnosis was associated with worse OC survival (HR= 1.19, 95% CI = 1.01–1.42). We observed an improved OS with the highest compared with the lowest OBS (HR = 0.46, 95% CI = 0.27–0.79, P for trend < 0.05). Notably, we also found an additive interaction between low OBS and high exposure to PM2.5, with the corresponding associations of PM2.5 being more pronounced among participants with lower OBS (HR = 1.42, 95% CI = 1.09–1.86). PM2.5 may blunt OC survival, but high OBS represented an antioxidative performance that could alleviate the adverse association of PM2.5 and OS.

We propose how to achieve synthetic PT $\mathcal{PT}$ symmetry in optomechanics without using any active medium. We find that harnessing the Stokes process in such a system can lead to the emergence of exceptional point (EP), i.e., the coalescing of both the eigenvalues and the eigenvectors of the system. By encircling the EP, both nonreciprocal optical amplification and chiral mode switching can be achieved. As a result, our synthetic PT $\mathcal{PT}$ -symmetric optomechanics works as a topological optomechanical amplifier. This provides a surprisingly simplified route to realize PT $\mathcal{PT}$ -symmetric optomechanics, indicating that a wide range of EP devices can be created and utilized for various applications such as topological optical engineering and nanomechanical processing or sensing.

Ambient particulate matter (PM) pollution in China continues to be a major public health challenge. With the release of the new WHO air quality guidelines in 2021, there is an urgent need for China to contemplate a revision of air quality standards (AQS). In the recent decade, there has been an increase in epidemiological studies on PM in China. A comprehensive evaluation of such epidemiological evidence among the Chinese population is central for revision of the AQS in China and in other developing countries with similar air pollution problems. We thus conducted a systematic review on the epidemiological literature of PM published in the recent decade. In summary, we identified the following: (1) short-term and long-term PM exposure increase mortality and morbidity risk without a discernible threshold, suggesting the necessity for continuous improvement in air quality; (2) the magnitude of long-term associations with mortality observed in China are comparable with those in developed countries, whereas the magnitude of short-term associations are appreciably smaller; (3) governmental clean air policies and personalized mitigation measures are potentially effective in protecting public and individual health, but need to be validated using mortality or morbidity outcomes; (4) particles of smaller size range and those originating from fossil fuel combustion appear to show larger relative health risks; and (5) molecular epidemiological studies provide evidence for the biological plausibility and mechanisms underlying the hazardous effects of PM. This updated review may serve as an epidemiological basis for China’s AQS revision and proposes several perspectives in designing future health studies.

Background: Non-optimum ambient temperature has not been widely perceived as an important environmental risk factor for asthma, and the association between ambient temperature and pulmonary function is rarely explored. Our study aimed to investigate the associations between non-optimum ambient temperature and pulmonary function among asthmatic adult patients. Methods: We performed a longitudinal study among 4,992 eligible adult asthmatic patients in 25 cities of China from 2017 to 2020. The patients were required to complete pulmonary function test every day in the morning and evening. Linear mixed-effects models and distributed lag non-linear models were used to evaluate the associations between ambient temperature and pulmonary function. Results: We evaluated 298,396 records of pulmonary function tests. We found inversely J-shaped exposure–response relationship curves for ambient temperature and pulmonary function. The effects of extreme low temperature occurred at lag 0 h and vanished at lag 72 h (almost 3 days). Compared with referent temperature (29.5 °C), extreme low temperature (−9.4 °C) was associated with decreases of 60.4 mL in FEV1, 299.7 mL/s in PEF, and 101.5 mL in FVC. Extreme high temperature (34.2 °C) was associated with decreases of 26.0 mL in FEV1, 35.8 mL/s in PEF, and 23.4 mL in FVC. Patients of male, overweight, and elder ages were vulnerable populations, and cold effects were more prominent in the south and in areas without central heating. Conclusions: Both extreme low and high ambient temperatures were associated with decreased pulmonary function in adult asthmatic patients. The effect could last for almost 3 days and low temperature was more harmful.

This paper proposes an image reconstruction method for simultaneous multi-slice imaging (SMS) by combining the virtual conjugate coil (VCC) technology and robust artificial-neural-networks for k-space interpolation (RAKI). This method can effectively improve the reconstruction quality, and is named VIRGINIA (VIRtual conjuGate coIls Neural-networks InterpolAtion). VIRGINIA utilizes the complex conjugate symmetry property of the virtual coil concept to generate virtual coil data for training, and obtains better image quality by applying the trained network to the original aliased SMS data. With experimental data, the VIRGINIA method was compared to other reconstruction methods (i.e., RAKI only and slice-GRAPPA) in terms of quantitative indices such as structural similarity index (SSIM), peak signal-to-noise ratio (PSNR) and root mean square error (RMSE). The results demonstrated that, under some certain slice-acceleration factors, VIRGINIA produced better reconstruction quality than those obtainable by Slice-GRAPPA and RAKI.

Exposure to greenness may lead to a wide range of beneficial health outcomes. However, the effects of greenness on preterm birth (PTB) are inconsistent, and limited studies have focused on the subcategories of PTB. A total of 3,751,672 singleton births from a national birth cohort in mainland China were included in this study. Greenness was estimated using the satellite-based Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index with 500-m and 1,000-m buffers around participants’ addresses. The subcategories of PTB (20–36 weeks) included extremely PTB (EPTB, 20–27 weeks), very PTB (VPTB, 28–31 week), and moderate-to-late PTB (MPTB, 32–36 weeks). Gestational age (GA) was included as another birth outcome. We used logistic regression models and multiple linear regression models to analyze these associations throughout the entire pregnancy. We found inverse associations between greenness and PTB and positive associations between greenness and GA. Specifically, an increase of 0.1 NDVI exposure within a 500-m buffer throughout the entire pregnancy was significantly associated with decreases in PTB (odds ratio [OR], 0.930; 95% confidence interval [CI], 0.927–0.932), EPTB (OR, 0.820; 95% CI, 0.801–0.839), VPTB (OR, 0.913; 95% CI, 0.908–0.919), MPTB (OR, 0.934; 95% CI, 0.931–0.936), and an increase in GA (β = 0.050; 95% CI, 0.049–0.051 weeks). These results suggest the potential protective effects of greenness on PTB and its subcategories: MPTB, VPTB, and EPTB in China.

With the continuous development of the power grid, power equipment becomes more complex and diverse, which has increased the workload of power maintenance personnel. This paper proposes a method of intelligent identification of distribution network equipment to reduce the power maintenance personnel's workload. The model needs device photos, GPS coordinates, and device topology information of the entire power grid to infer the possible situation of the current device. The model is mainly divided into two parts: target recognition and equipment prediction. In target recognition, we propose a Self-attention target detection network (SA-TDN) that combines Faster-RCNN and Attention mechanism. In equipment prediction part, we use KD-Tree to analyse the grid topology to predict the real identification of the device. We compared this model with other convolutional neural networks (CNN) classification models. The results show that our model is ahead of current models in prediction accuracy.

Energy demand forecast has an important practical significance for the sustainable development of the national economy, the reasonable allocation of resources, and the construction of modernization goals. This study is based on the analysis of coal, electricity, natural gas, and other energy data in Yunnan Province from 2011 to 2018 and uses long short-term memory, sequence to sequence, deep learning, and ridge regression coupling methods to construct an energy demand forecast model in Yunnan Province. Forecast results show the following. The total energy consumption of Yunnan Province from 2021 to 2025 will continue to increase. Moreover, the coal consumption of Yunnan Province will continue to decline from 2021 to 2025. Furthermore, the electricity consumption of Yunnan will increase by about 8.02% year-on-year from 2021 to 2025. The experiment proves that the forecasting effect of the energy demand forecast model proposed in this study is excellent.

In order to forecast the number of electric vehicles in Yunnan Province, based on BASS model, this paper uses extensive analogy method to explore the acquisition of m, p and q model parameters, forecasts the purchasing power of the market, and estimates the innovation coefficient and imitation coefficient from three aspects of high potential scenario, base potential scenario and low potential scenario. The number of new energy electric vehicles in Yunnan Province in three scenarios from 2022 to 2035 is predicted. The forecast results show that under the condition of high potential development, the number of new energy vehicles in Yunnan Province will reach 409,600 in 2022; in the case of benchmark potential development, the number of new energy vehicles will reach 291,400 in 2022; in the case of low potential development, the number of new energy vehicles in Yunnan Province will reach 155,400 in 2022.

The paper introduced application of microseismic monitoring system in forecasting roof weighting of Qianqiu Coal Mine. The practical result showed that the microseismic monitoring system can forecast and judge the first weighting of main roof of fully mechanized caving face; data of microseismic monitoring is consistent with data of drill cuttings quantity and rock pressure monitoring, and using comprehensive forecasting technology of rock burst can forecast stope dynamic disasters more effectively; taking frequency of large energy events as effective parameter of microseismic monitoring system can exactly forecast stope dynamic phenomenon and summarize precursor information model of main roof weighting, and the conclusion can effectively prevent stope dynamic phenomena and rock burst accidents.

A new scheme of quantization which was constructed by an optimal quantization matrix was proposed.It was inefficient for the traditional quantization of MPEG video encoders on the general DSPs.Considering the traits of a DSP,which could realized one-step quantization by substituting shift for division.Meanwhile,this scheme used different quantization strategies according to the differences of the types of video blocks to be coded,and avoids the loss of the quality of images with the unified quantization.Experiments had shown that this scheme could obviously improve the efficiency of quantization,and subjective and objective quality of images coded as well.

Serine and Arginine Rich Splicing Factor 1 (SRSF1) is a splicing factor that binds to exonic enhancers and stimulates splicing and is previously implicated with autoimmunity. Herein, we investigate the role of SRSF1 in regulating innate immune functions that are pertinent in the pathogenesis of auto-inflammatory diseases. Specifically, we show that conditional deletion of SRSF1 in mature lymphocytes resulted in higher expression of il-17a and il-17 f and an expansion of IL17A+ CD8 T cells. Mechanistically, the aberrant expression of IL-17A in SRSF1 cKO mice could not be attributed to alternative splicing of il-17a or il-17 f genes but possibly to defective CD11B+LY6C+ myeloid derived suppressor function in the spleen. Finally, meta-analysis of RNA-Seq collected from psoriasis patients demonstrate a clear correlation between SRSF1 and psoriasis that suggests a putative role of SRSF1 in IL-17A-induced psoriasis.