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Abstract This study investigates the incidence of Class B respiratory infectious diseases (RIDs) in China under the Coronavirus disease 2019 (COVID-19) epidemic and examines variations post-epidemic, following the relaxation of non-pharmaceutical interventions (NPIs). Two-stage evaluation was used in our study. In the first stage evaluation, we established counterfactual models for the pre-COVID-19 period to estimate expected incidences of Class B RIDs without the onset of the epidemic. In the second stage evaluation, we constructed seasonal autoregressive integrated moving average intervention (SARIMA-Intervention) models to evaluate the impact on the Class B RIDs after NPIs aimed at COVID-19 pandemic were relaxed. The counterfactual model in the first stage evaluation suggested average annual increases of 10.015%, 78.019%, 70.439%, and 67.799% for tuberculosis, scarlet fever, measles, and pertussis respectively, had the epidemic not occurred. In the second stage evaluation, the total relative reduction in 2023 of tuberculosis, scarlet fever, measles and pertussis were − 35.209%, − 59.184%, − 4.481%, and − 9.943% respectively. The actual incidence declined significantly in the first stage evaluation. However, the results of the second stage evaluation indicated that a rebound occurred in four Class B RIDs after the relaxation of NPIs; all of these showed a negative total relative reduction rate.

In the scenario where multi-autonomous surface vehicles(ASVs) round up an actively escaped adversarial target, a game model of the multi-ASV cooperative hunting problem was established using differential game theory. A surround term consisting of the escape angle was introduced into the payment function which included the distance cost so that the escape probability of the target was reduced. At the same time, the hunting problem was converted into an optimization problem for solving achievable strategies, and the particle swarm optimization(PSO) algorithm was used to solve the optimal strategy that satisfied the Nash equilibrium. The simulation and lake test results show the effectiveness of the hunting algorithm based on differential game and PSO.

To obtain energy-saving obstacle avoidance paths of autonomous undersea vehicles(AUVs) in the current environment, a three-dimensional dynamic current environment model based on current field velocity information and underwater topographic obstacles was established. The augmented objective function was established based on navigation energy consumption, AUV maneuvering performance, and obstacle constraints, and an improved particle swarm optimization-Lévy(PSO-Lévy) algorithm based on weight adjustment mechanism and random wandering mechanism was proposed. The parameter adjustment strategy based on the optimal damping ratio and the random step wandering strategy based on the Lévy-flight process were introduced into the PSO algorithm. By executing a long-step wandering operation and regulating the velocity inertial of particles with a certain probability, the PSO algorithm could get a longer step and jump out of the local optimum. The simulation results show that the proposed algorithm can plan the optimal path with low energy consumption according to the current information while effectively avoiding obstacles.

1,2-Dichloroethane (1,2-DCE) is a powerfully toxic neurotoxin, which is a common environmental pollutant. Studies have indicated that 1,2-DCE long-term exposure can result in adverse effects. Nevertheless, the precise mechanism remains unknown. In this study, behavioral results revealed that 1,2-DCE long-term exposure could cause anxiety and learning and memory ability impairment in mice. The contents of γ-aminobutyric acid (GABA) and glutamine (Gln) in mice’s prefrontal cortex decreased, whereas that of glutamate (Glu) increased. With the increase in dose, the activities of glutamate decarboxylase (GAD) decreased and those of GABA transaminase (GABA-T) increased. The protein and mRNA expressions of GABA transporter-3 (GAT-3), vesicular GABA transporter (VGAT), GABA A receptor α2 (GABAARα2), GABAARγ2, K-Cl cotransporter isoform 2 (KCC2), GABA B receptor 1 (GABABR1), GABABR2, protein kinase A (PKA), cAMP-response element binding protein (CREB), p-CREB, brain-derived neurotrophic factor (BDNF), c-fos, c-Jun and the protein of glutamate dehydrogenase (GDH) and PKA-C were decreased, while the expression levels of GABA transporter-1 (GAT-1) and Na-K-2Cl cotransporter isoform 1 (NKCC1) were increased. However, there was no significant change in the protein content of succinic semialdehyde dehydrogenase (SSADH). The expressions of adenylate cyclase (AC) and cyclic adenosine monophosphate (cAMP) contents were also reduced. In conclusion, the results of this study show that exposure to 1,2-DCE could lead to anxiety and cognitive impairment in mice, which may be related to the disturbance of GABA metabolism and its receptors along with the cAMP-PKA-CREB pathway.

A hybrid UHVDC transmission system applying LCC as the rectifier and MMC as the inverter combines the advantages of both converter types, which makes this protection scheme more complicated. A new pilot protection scheme for a three-terminal hybrid DC transmission system applying energy functions is proposed. The energy function for LCC is applied to MMC to derive the energy level of the hybrid system. Furthermore, an improved Hausdorff distance (IHD) algorithm is proposed to detect the difference in energy levels between the normal and fault states. An abrupt change in energy level is characterized by IHD change rate. Time points at which the IHD change rate exceeds the threshold at converter stations are applied to determine the fault line and to estimate the fault section. The proposed protection scheme is then verified by a simulation model of the Wudongde ±800 kV three-terminal hybrid UHVDC transmission project. The appropriate sampling frequency is selected for a real-time calculation, and the threshold is selected considering the effect of noise. Results show the proposed scheme can identify and trip fault lines quickly and effectively, even for a 600 Ω grounding fault. Other waveshape similarity algorithms are compared and analyzed. Compared with existing protection schemes, the proposed scheme transmits less data to improve communication speed and reliability.

We established a government cloud platform-based epidemiological survey information management system to improve the capability of response to public health emergencies in Liaoning province. By using big data, cloud computing, image recognition, speech recognition, fifth generation (5G), geographic information systems (GIS) and other technologies, the system takes the advantages of government cloud platform including strong computing power, safe and reliable data exchange, flexible server deployment, and efficient data collection. The system could be used to construct multi-dimensional transmission model of epidemics, to conduct big data analysis, to link the data collected at provincial/municipal and district levels, to assist real-time cross-provincial collaborative investigation, and to carry out closed-loop management on the information of joint prevention and control of epidemic. The established system came into operation in August 2021 in Liaoning province and played an important role in regional epidemic control and prevention.

Abstract Background Severe fever with thrombocytopenia syndrome (SFTS), one kind of tick-borne acute infectious disease, is caused by a novel bunyavirus. The relationship between meteorological factors and infectious diseases is a hot topic of current research. Liaoning Province has reported a high incidence of SFTS in recent years. However, the epidemiological characteristics of SFTS and its relationship with meteorological factors in the province remain largely unexplored. Methods Data on reported SFTS cases were collected from 2011 to 2019. Epidemiological characteristics of SFTS were analyzed. Spearman’s correlation test and generalized linear models (GLM) were used to identify the relationship between meteorological factors and the number of SFTS cases. Results From 2011 to 2019, the incidence showed an overall upward trend in Liaoning Province, with the highest incidence in 2019 (0.35/100,000). The incidence was slightly higher in males (55.9%, 438/783), and there were more SFTS patients in the 60–69 age group (31.29%, 245/783). Dalian City and Dandong City had the largest number of cases of SFTS (87.99%, 689/783). The median duration from the date of illness onset to the date of diagnosis was 8 days [interquartile range (IQR): 4–13 days]. Spearman correlation analysis and GLM showed that the number of SFTS cases was positively correlated with monthly average rainfall (r s = 0.750, P

Abstract A converter station is the hub of a High Voltage Direct Current (HVDC) transmission project, and the neutral bus arrester on its rectifier side has the most complex operation condition. The ideal operating condition of a multicolumn parallel arrester is the equipartition of energy generated when the system is impacted. When this condition is not achieved, individual arrester units with lower residual voltage absorb more energy than their tolerance level, which leads to breakdown failure of the arrester and forced outage of the DC system, resulting in significant economic losses. In this paper, the influence of the internal structure, assembly technology, and installation mode of a multicolumn parallel arrester on the operation status of an arrester is analysed, the quality control measures are summarized, and suggestions for site maintenance are given first. Then, the current sharing characteristics of large capacity multicolumn parallel arresters under different current waveforms, different current amplitudes and different temperatures are studied through experiments. The results show that the impact current waveform has little influence on the current non‐uniformity coefficient and generally does not exceed the standard value; under long duration current shock, the current deviation coefficient (CDC) may increase or decrease with increasing temperature. The above conclusions provide a practical basis and theoretical basis for the study of multicolumn parallel arrester operation condition monitoring methods, such as the selection of state characteristics and the formulation of monitoring criteria.

Since the last IAEA-FEC in 2021, significant progress on the development of long pulse steady state scenario and its related key physics and technologies have been achieved, including the reproducible 403 s long-pulse steady-state H-mode plasma with pure radio frequency (RF) power heating. A thousand-second time scale (∼1056 s) fully non-inductive plasma with high injected energy up to 1.73 GJ has also been achieved. The EAST operational regime of high β _P has been significantly extended ( H _98y2 > 1.3, β _P ∼ 4.0, β _N ∼ 2.4 and n _e / n _GW ∼ 1.0) using RF and neutral beam injection (NBI). The full edge localized mode suppression using the n = 4 resonant magnetic perturbations has been achieved in ITER-like standard type-I ELMy H-mode plasmas with q _95 ≈ 3.1 on EAST, extrapolating favorably to the ITER baseline scenario. The sustained large ELM control and stable partial detachment have been achieved with Ne seeding. The underlying physics of plasma-beta effect for error field penetration, where toroidal effect dominates, is disclosed by comparing the results in cylindrical theory and MARS-Q simulation in EAST. Breakdown and plasma initiation at low toroidal electric fields (

Abstract Background To analyze and discuss the transmission route of a cluster of cases of severe fever with thrombocytopenia syndrome bunyavirus (SFTSV). Method We performed an epidemiological investigation and a genetic analysis of patients with severe fever with thrombocytopenia syndrome (SFTS) caused by SFTSV, their close contacts and the surrounding population. Results We found that all patients had contact with the blood of the first patient. The comparison of gene sequences in the three isolated SFTSV strains showed that the strains were closely related. Six close contacts and nine individuals in the surrounding population were positive for SFTSV IgM antibody. Conclusion We suspect that the cluster outbreak was transmitted via blood and that the natural reservoir host of SFTSV exists in the patients’ environment.

Abstract Background Restoration projects have been implemented worldwide to mitigate the adverse effects of the loss and degradation of wetland habitats. Much research has been carried out on the impacts on birds of wetland restoration and management projects in China. Studies have mainly investigated central or coastal wetlands, while inland wetlands in remote areas have been much less studied. We focused on examining the response of wild birds to wetland restoration in Dianchi Lake, south-west China. Methods The line transect method was performed at 26 sampling plots. Three of these were in the city, and to acquire all wild bird data 23 plots were located every 2–8 km along the shore of Dianchi Lake, between December 2011 and November 2013. We collected all related bird records by searching the available literature, articles, newspapers and records of birdwatchers to compare species variation before and after implementation of wetland restoration. To measure the relationships between waterbird assemblages and habitat structures, we used canonical correspondence analysis (CCA) to pair the main matrix of bird assemblages with a second matrix of habitat variables. Results We recorded 182 bird species belonging to 51 families and 17 orders. Of the species, 42 were new records for Kunming City and 20 were new records for Yunnan Province. Ten waterbird species were found to have disappeared from the shore of Dianchi Lake. CCA results indicated that waterbirds could be divided into four categories based on their habitat preference: synanthropic (wintering gulls), special habitat (shorebirds), semi-natural (wintering coots and ducks) and disturbance-tolerant (resident) species. Conclusions Our study is the first to consider the entire wild bird community throughout the year and discuss the species variation before and after wetland restoration projects launched for Dianchi Lake. Distinct habitat requirements of different waterbird groups were detected in our study, suggesting different types of restoration and management should be implemented.

In applications of pulse-width modulation (PWM) rectifiers, the high quality of the DC power is required. The fluctuation of grid voltage and the switching of equipment connected to the DC supply are likely to cause a sudden change in the DC-link voltage, resulting in equipment instability or even damage. Considering the bandwidth of the closed-loop current dynamic, this paper presents a novel DC-link voltage control strategy of PWM rectifiers based on the reduced-order linear extended state observer (RLESO). Using a first-order RLESO to observe and even compensate the model variations caused by grid voltage and DC-link voltage fluctuations or load transients, the proposed method can effectively improve the dynamic performance against grid and load disturbances, as well as for sudden changes in DC-link reference voltage. Combined with frequency domain analysis, this paper theoretically analyzes the sensitivity, stability, and tracking performance of the proposed method, providing a basis for the selection of controller parameters. And finally, simulation and experimental results are presented to demonstrate its validity and the superiority over the traditional PI control strategy.

Anthrax is a continuous threat in China, especially in rural regions. In July 2015, an anthrax outbreak occurred in Xifeng County, Liaoning Province. A total of 10 cutaneous anthrax cases were reported, with 210 people under medical observation. In this study, the general characteristics of human anthrax outbreak occurred in Liaoning Province were described, and all cases were caused by butchering and contacting sick animal. Meanwhile, the phylogenetic relationship between outbreak-related isolates/samples of the year 2015 and previous Bacillus anthracis strains was analyzed by means of canonical single nucleotide polymorphisms (canSNP), multiple-locus variable-number tandem repeat analysis (MLVA) with 15 markers and single-nucleotide repeats (SNR) analysis. There are two canSNP subgroups found in Liaoning, A.Br.001/002 and A.Br.Ames, and a total of six MLVA 15 genotypes and five SNR genotypes were observed. The strain collected from anthrax outbreak in Xifeng County in 2015 was classified as A.Br.001/002 subgroup and identified as MLVA15-29 genotype, with same SNR profile (CL10: 17, CL12: 15, CL33: 29, and CL35: 13). So we conclude that the same clone of B.anthracis caused the anthrax outbreak in Xifeng County in 2015, and this clone is different to previous isolates. Strengthening public health education in China is one of the most important measures to prevent and control anthrax.