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In order to investigate the effect of mixed-mold fermentation on the bacterial community structure and quality of fish sauce made from mandarin fish viscera, changes in the bacterial community structure of mandarin fish viscera inoculated with a mixture of Aspergillus oryzae and Monascus (fish sauce A) or Aspergillus niger (fish sauce B) at a ratio of 3:1 during the fermentation process were analyzed using high-throughput sequencing. Additionally, changes in various quality parameters including pH, total acid content, amino nitrogen content, total soluble nitrogen content, total volatile basic nitrogen (TVB-N) content, volatile component contents, and free amino acid contents were evaluated. The results showed that mixed-mold fermentation significantly influenced the bacterial community. The diversity of bacterial community decreased during the fermentation process. Staphylococcus was found to be the dominant genus. The pH of fish sauce A and B decreased significantly, and consequently the content of total acids increased significantly throughout the fermentation. At the end of fermentation, the contents of amino nitrogen were 1.23 and 1.02 g/100 mL in fish sauce A and B, respectively, and the contents of total soluble nitrogen were 1.62 and 1.53 g/100 mL, respectively, both of which meet the standard for first-grade fish sauce. The TVB-N contents of fish sauce A and B were 152.81 and 154.12 mg/100 mL, respectively, complying with the national limit requirements. Gas chromatography-mass spectrometry (GC-MS) analysis identified 48 and 54 volatile components in fish sauce A and B, respectively, with the major one being 2,5-dimethylpyrazine at concentrations of 192.79 and 169.04 µg/mL, respectively. The contents of umami taste amino acids and sweet amino acids were significantly higher in fish sauce A and B than in unfermented fish sauce (P < 0.05). The correlation analysis results indicated that Staphylococcus made the greatest contribution to the quality of fish sauce and played a significant role in the formation of key characteristic flavor compounds in the late stage of fermentation. Overall, mixed-mold fermentation could effectively improve the quality of fish sauce. Fish sauce A had higher contents of amino nitrogen and total soluble nitrogen compared with fish sauce B, and consequently better overall quality.

In this commentary, we elucidate two distinctive characteristics of China's primary health care system relative to the global primary health care framework: a more narrowly defined patient population and scope of services, along with a diminished clinical capacity in primary care. Building upon this foundation, we critically examine and juxtapose the two quintessential theoretical-practical models of the 20th century that are intimately linked with the integration of medication and prevention. They are the "Community-Oriented Primary Care" Model and the "Barefoot Doctor" Model. Additionally, leveraging a series of practical cases observed within Shanghai's primary care settings in the fourth quarter of 2023, we deliberate on viable approaches for adapting and applying these models in China's primary care infrastructure. We further delineate the requisite external conditions for such a transformation and offer targeted recommendations for the deployment of these models across diverse locales.

In-depth interview is to understand the life experience and lifestyle of a certain social group through in-depth conversation with the respondents, explore the formation process of specific phenomena, and propose ideas and recommendations to solve problems. In-depth interview has been widely used in the study of primary care research. Thus, understanding its basic concept and mastering the design and application process are essential to master this method. This paper comprehensively describes the research process of in-depth interview research according to the 3 stages at before, during and after the research. Before formally conducting in-depth interview research, researchers need to understand its basic concepts, characteristics and limitations related to the research purpose and process, and identify which studies are applicable. In the design and implementation of in-depth interview research, researchers should focus on the main steps of the research in four stages: recruitment of interviewees, design and modification of interview guide, collection of interview data, and analysis of interview data. After completing the data analysis of the in-depth interview, researchers need to write a research paper referring to the report specification of qualitative research to increase the credibility of research results and the transparency of the research process. In addition, this paper recommends five fields suitable for in-depth interviews in primary care research, and introduces learning resources for researchers to master in-depth interview methods. Through the introduction of in-depth interview research method, this paper aims to help researchers in the field of general practice/primary care to master a method suitable for scientific research, and provide methodology reference for improving the quality of qualitative research in this field in China.

In order to investigate the effect of a recirculating aquaculture system on the body indexes, texture, nutrient composition and earthy odor substances of largemouth bass (Micropterus salmoides), this study determined texture characteristics of fish meat such as hardness, springiness and chewiness, and used conventional biochemical methods, an amino acid automatic analyzer, and gas chromatography (GC) to detect the contents of moisture, ash, crude protein, crude fat, fatty acids, and amino acids. Meanwhile, gas chromatography-mass spectrometry (GC-MS) and electronic tongue were used to analyze the earthy odor substances and taste of fish meat. The results showed that the ratio of liver to body mass decreased significantly with rearing time; after rearing for up to 20 days, the hardness, cohesiveness, chewiness, springiness, adhesiveness and gumminess of fish meat were improved compared with those before rearing. The crude fat content initially increased and then decreased with rearing time, while the moisture content showed an opposite trend. The contents of protein, ash, flavor amino acids, essential amino acids, and monounsaturated fatty acids in fish meat increased after 15 days of rearing. The contents of sum of eicosapentaenoic acid methyl ester, docosahexaenoic acid methyl ester and ω-3 fatty acids significantly increased after 5 and 15 days. In addition, the contents of water-soluble protein and non-protein nitrogen in fish meat also increased significantly; with increasing rearing time, fish meat showed an increase in flavor differences, and the content of earthy odor substances decreased, which was below the sensory threshold from day 15 onward. Taking into account the body indexes, nutrient composition and earthy odor substances of largemouth bass muscle, a rearing period of 15 days in the recirculating water system is recommended.

Typhoons are among the most significant natural disasters affecting the eastern and southern coastal regions of China, inflicting substantial annual damage on both coastal and inland areas. Since the initiation of the reform and opening-up policy, the socioeconomic development of the coastal regions of China has been swift, leading to increased exposure to typhoons. In the context of global climate change, typhoons are expected to increase in frequency and intensity in China. Therefore, researching on the spatiotemporal pattern characteristics of typhoons impacting China is of critical importance for understanding the impact patterns and risk changes of typhoon disasters, as well as for formulating policies on disaster response, prevention, and mitigation. This study aims to provide valuable insights into the formulation of such policies. Based on these objectives, this study utilized a comprehensive dataset, including county-level socioeconomic and disaster statistics, historical typhoon wind and rainfall data, and high-precision topographic data. Using county-level administrative regions as spatial units, this study employed various methods, such as time-series statistical analysis, gravity model, geographical detector, spatial correlation analysis, and geographically weighted regression, to analyze the spatiotemporal distribution patterns and influencing factors of typhoon disaster conditions in China from 1978 to 2020. The findings of this study are as follows: (1) The number of deaths and missing persons, quantity of damaged housing, death, and missing rate per million people, and proportion of direct economic loss to GDP caused by typhoon disasters have all shown a declining trend, indicating significant achievements in disaster prevention and mitigation efforts. (2) The center of gravity of typhoon disaster-related losses has shifted southward, corresponding with the economic development of coastal regions, demonstrating a reduced disaster impact in coastal areas and an increased impact in inland areas. (3) Wind and rain induced by typhoons are the primary driving factors of disaster conditions, and topographical factors are also drivers of casualties and crop loss. (4) The two major regions, Zhejiang-Northern Fujian and Western Guangdong-Eastern Guangxi, exhibit significant characteristics of disaster condition agglomeration, closely related to typhoon activity patterns and levels of economic development. (5) There is a negative correlation between the gross local product and disaster conditions in some areas, reflecting the role of socioeconomic development in enhancing the capacity for disaster prevention and mitigation.

The real-time transmission of online monitoring data for high-voltage transmission equipment in remote areas is a difficult problem in practical applications due to the lack of network. For this purpose, the article designs an online monitoring system for high-voltage transmission equipment based on ubiquitous IoT and LoRa technology. It constructs a low-power, long-distance LoRa wireless communication self-organizing network, transmits the transmission equipment status information and other data collected by front-end sensors to the LoRaWAN gateway, and then uploads the data to the back-end server through a 5G wireless network to achieve the overall communication link of the online monitoring system. The simulation experiment results show that compared with the existing technical solutions ZigBee, LoRa, and NB-IoT, using the scheme designed in the article, the system transmission speed (20-100 kbit/s) is the fastest, and the packet loss rate, transmission delay, and average time consumption (1.6%, 0.27s, and 60s, respectively) are the lowest. This indicates that the system not only has a fast transmission speed but also takes into account the characteristics of low power consumption and long distance, achieving stable data transmission, and is suitable for online monitoring of high-voltage transmission equipment in remote areas.

ObjectiveTo evaluate the exposure levels and health risks of aflatoxins （AFT） in dried chili and chili powder sold in Shandong Province.MethodsAFT in chili and chili powder samples were determined using liquid chromatography-triple quadrupole mass spectrometry， and aflatoxin exposure was calculated using the point evaluation method.ResultsThe detection rate of AFTB1 was the highest in the 120 samples of dried chili and chili powder investigated， at 21.7% （26/120）. The proportion of samples exceeding the national standard limit was 8.3% （10/120）； the qualification rate was 91.7% （110/120）. The detection rate of AFTB2 was 19.2% （23/120）， that of AFTG1 was 5.0% （6/120）， and that of AFTG2 was 0.8% （1/120）. The detection rate of AFT in chili powder was significantly higher than that of dry chili samples （P

Background It is important to estimate the sodium intake of primary hypertension patients through 24-hour urine sodium excretion, but the collection and testing processes are complicated. It is not clear whether the existing equation for estimating 24-hour urinary sodium excretion from spot urine sample is valid in Chinese primary hypertension patients. Objective To evaluate the validity of the Kawasaki, INTERSALT, and Tanaka equations using spot urine samples to estimate 24-hour urinary sodium excretion among Chinese primary hypertension patients. Methods This study retrospectively selected hospitalized primary hypertension patients from Department of Cardiology Peking University International Hospital from March 2018 to March 2021. General data were collected. The 24-hour urinary sodium extraction in the 24-hour urine sample was measured. The 24-hour urinary sodium extraction from spot urine sample was estimated. Paired t-test was used to measure the significance of difference between the 24-hour urine sodium excretion from spot urine samples predicted using Kawasaki, INTERSALT or Tanaka equation and measured 24-hour urinary sodium excretion from 24-hour urine collections, and the correlation and agreement between them were analyzed using the Spearman correlation coefficient and Bland–Altman plots, respectively. Relative deviation was calculated. The accuracy of the three equations were also evaluated in patients with different levels of salt intake, diabetes or proteinuria. Results One hundred and ninety-six patients were finally included for analysis. The average 24-hour urinary sodium excretion level was (165.04±78.53) mmol/d, which was equivalent to daily NaCl intake of (9.65±4.59) g/d. Female patients were older, had higher ratios of microalbuminuria and proteinuria, while lower BMI, diastolic blood pressure on admission, 24-hour average diastolic blood pressure compared with male patients (P0.05) without significant difference, and the Bland-Altman plots showed that 96.43% spots were in 95%CI. The relative deviation of Kawasaki, INTERSALT and Tanaka equations was -31.82%, 12.94 % and -1.90%, respectively. After dividing patients according to salt intake, the moderate correlation between predicted and actual values of each equation was no longer significant. There was no significant difference in the predictive accuracy of the equations between patients with and without diabetes or proteinuria. Conclusion The accuracy and consistency of the Kawasaki, INTERSALT and Tanaka equations in estimating 24-hour urinary sodium levels by spot urine in primary hypertension patients were poor. Tanaka's overall estimated value is the closest to the measured mean value. No comorbidity (such as diabetes, proteinuria) that might affect urinary sodium excretion was found to have a significant effect on the accuracy of the estimation equation.

Objective To investigate the value of U-wave inversion combined with fragmented QRS (fQRS) on electrocardiogram in predicting the prognosis after percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS). Methods A total of 123 patients with ACS admitted to The Third People’s Hospital of Henan Province from October 2017 to September 2019 were included. All the patients underwent PCI after electrocardiogram examination, followed by 3 months follow-up. The percentages of U-wave inversion, fQRS, and a poor prognosis were analyzed to determine the predictive value of U-wave inversion combined with fQRS for post-PCI outcome in patients with ACS. Results Among the 123 patients with ACS, the percentages of U-wave inversion, fQRS, and a poor prognosis were 39.84%, 33.33%, and 23.58%, respectively. The patients with a poor outcome showed significantly higher percentages of U-wave inversion and fQRS than those with a good outcome (χ2=20.547,26.080,P

To further reduce the friction coefficient of zinc-aluminum coatings, tin (Sn) powder was introduced into waterborne chromium-free zinc-aluminum coatings. The coatings were evaluated and analyzed in terms of hardness, adhesion, impact resistance, salt spray resistance, electrochemical properties, friction coefficient and micro morphology. The impact of varying amounts of Sn powder on the mechanical properties, corrosion resistance and tribological performance of the coatings was investigated. Results showed that the introduction of tin powder into zinc-aluminum coatings effectively enhanced the toughness of the coatings. When the added amount of Sn powder was 5%～10% (mass fraction, the same below), the hardness of the coatings did not decrease, and both adhesion and impact resistance were significantly improved; the addition of Sn powder was also found to improve the lubrication performance of the coating, reducing its friction coefficient. When the content of Sn powder reached 10%～20%, both the thread friction coefficient and the support surface friction coefficient were reduced to below 0.15. More importantly, the introduction of Sn powder was found to enhance the corrosion resistance of the coating. Results from neutral salt spray tests and electrochemical testing indicated that the coatings exhibited relatively better corrosion resistance when the Sn powder content was 10%.

Aerogel/fiber composites have shown a wide range of applications in aerospace, defence, environmental management and biomedicine due to their high porosity, low bulk density, high specific surface area and low thermal conductivity.The thermal and mechanical properties and interfacial compatibility of aerogel/fiber composites was reviewed, the heat transfer mechanism, mechanical property enhancement mechanism and interfacial compatibility bonding mechanism was introduced, and the effect of different fiber embedding on the final properties of the composites considering different fiber volume fractions and fiber multiscale i.e. different fiber diameters (aspect ratio) and pore diameters between fibers was summarized in this paper. Finally, the prospective future of the research directions of aerogel/fiber composites were proposed, including heat resistance, improved mechanical properties and material interface bonding.

Owing to the unique lattice structure， graphene has very superior properties， but zero band gap has always restricted the development of graphene.Laser-induced graphene (LIG) technology can significantly enhance the performance of graphene，but LIG technology is still limited with small band gap， few capacitor sites and lamellar stacking problems.By doping LIG with heterogeneous atoms/nanoparticles， the microstructure， surface chemical activity and porosity of graphene can be regulated for improving the performance of LIG composite materials，which can provide the novel strategy of the development and application of LIG device.In this work， the doping systems of LIG in recent years were reviewed， and the effect of many heterogeneous atoms/nanoparticles doping on the structure and performance of LIG was analyzed.The characteristics of many LIG doping methods were expounded， and the application of doped LIG devices in various related fields was discussed，providing research ideas for developing artificial intelligence，energy storage and conversion，and health detection application devices by combining the characteristics of doped LIG with device performance.In the end， the LIG doped with heterogeneous atom/nanoparticles was summarized， and its development prospects were prospected.

Under the influence of mining, the overlying strata of shallow coal seam fully mechanized top coal caving face collapses and forms cracks that connect with the surface. The vertical air leakage caused by these cracks has a significant impact on the spontaneous combustion of coal in the goaf. In order to study the vertical air leakage law of surface in goaf of shallow coal seam under different seasonal conditions, SF6 gas tracing method is used to measure the vertical air leakage on the 122108 working face of Shaanxi Coal Caojiatan Mining Co., Ltd. in four seasons: winter, spring, summer, and autumn. The temperature, atmospheric pressure, and air leakage rate changes on the surface and underground goaf during different seasons are analyzed. The results show the following points. ① In winter, the temperature difference between the surface of the working face and the underground goaf is relatively large, with a maximum temperature difference of 37.7 ℃. In summer, the temperature difference between the surface of the working face and the underground goaf is relatively small, with a minimum temperature difference of only 0.9 ℃. The maximum pressure difference between the surface of the working face and the underground goaf in winter is 40.37 hPa. The maximum pressure difference between the surface of the working face and the underground goaf in summer is 22.47 hPa. The temperature difference and pressure difference between the surface and underground goaf of the working face in spring and autumn are not significantly different. ② The winter air leakage rate is relatively high, with an average maximum air leakage rate of 8.364 m/min. The air leakage rate in summer is relatively small, with an average maximum air leakage rate of 6.918 m/min. The air leakage rates in spring and autumn are not significantly different. ③ When close to the working face, the air leakage rate is relatively high. According to the vertical air leakage law on the surface, measures such as underground pressure equalization, sealing of inlet and outlet air corners, and surface crack coverage can be taken to ensure the safe mining of 122108 working face.

Deoxynivalenol (DON) contamination in cereals and cereal products has the potential to pose a threat to human health. The biodetoxification technique, which uses biological enzymes to transform mycotoxins into less toxic product, is an environmentally friendly and highly effective approach to detoxifying mycotoxins. In this study, a gene designated adh2, encoding DON detoxifying enzyme, was identified by homology search from the genome sequence of DON-detoxifying strain Devosia sp. FJ2-5-3. Subsequently. The adh2 gene was cloned and expressed. Then, the enzymatic properties of its encoding enzyme was further characterized. The results showed that the length of the adh2 gene in Devosia sp. FJ2-5-3 was 1770 bp and the encoded ADH2 enzyme consisted of 589 amino acids, with a signal peptide of 24 amino acids length present at the N-terminus and belonging to type I of the PQQ-dependent alcohol dehydrogenase family (Type I PQQ-ADH). The enzyme exhibited the optimal activity at pH 9 and a temperature of 35 °C, and it retained over 50% of enzyme activity after incubation at 65 ℃ for 4 hours, indicating its good thermal stability. In addition, Ca2+ was found to be an essential cofactor for ADH2, while both 1% of ethanol and isopropanol showed significant inhibitory effects on its activity. The Km and Kcat values of ADH2 for DON were 708.00±47.01 μg/mL and 3.37±0.11 S–1, respectively. These results could provide reference information for the subsequent industrial application of DON detoxification enzymes.

High-energy and high-intensity proton accelerators in the range of several MW are widely applied in the fields of the nuclear industry, civil applications and fundamental researches. In this scenario, a high power circular accelerator complex consisting of a 100 MeV pre-injector cyclotron, a 800 MeV injector ring cyclotron and a 2 GeV continuous wave (CW) fixed field alternating gradient accelerator (FFA) was proposed at China Institute of Atomic Energy. The development of the 44.4 MHz high power waveguide type RF cavity with high quality factor and high shunt impedance is extremely important for 2 GeV CW FFA. In order to acquire the fabrication technology and operation experience of the boat shape cavity, R&D on a 177.6 MHz quarter scaled prototype cavity was conducted. The power dissipated on the prototype surface can reach hundreds of kW, resulting in thermal stress of the cavity. Under the combined action of thermal stress, gravity, atmospheric pressure and mechanical constraint, the cavity frequency shifts. Therefore, it is necessary to resist the deformation of the cavity through various measures such as cooling water and changing the external forces on the cavity, and adjust the frequency to the design range. Solid-thermal coupling method and fluid-solid-thermal coupling method were used to carry out the multi-physical simulation of the cavity respectively, and the distribution of power loss in the surface, temperature field, stress field and deformation field of the boat shape cavity was calculated in the process. The effect of different force and the influence of the deformation of the cavity on the frequency were analyzed. The result by the fluid-solid-thermal coupling method shows that the cavity temperature near the inlet area is lower than that in the outlet area. However, the results calculated by solid-thermal coupling method show that the cavity temperature distribution on the two regions is almost equal. The above results show that the fluid-solid-thermal coupling method are more consistent with the actual physical process. The temperature field distribution obtained by the two methods has slightly different influence on the deformation field and the frequency adjustment range, but the solid-thermal coupling method requires less computer configuration, simpler model processing and slightly faster calculation speed. For the quarter scaled cavity, the results obtained by the two thermal simulation methods are generally consistent, and the solid-thermal coupling simulation methods in practical application are sufficient to meet the requirements of engineering design.

In order to investigate the mechanical properties of uncured rubber, uniaxial and cyclic tensile experiments are conducted on uncured rubber at different strain rates. From the experimental results, the rate-dependent nonlinear mechanical behaviors of uncured rubber can be clearly observed. With strain rate increasing, the stress level, hysteresis and Mullins effect get enhanced, and the residual strain decreases. To characterize the nonlinear visco-elastoplastic mechanical behaviors of uncured rubber, a three-network (TN) constitutive model that contains a hyperelastic network and two nonlinear viscoplastic networks is proposed. The eight-chain model is used to characterize the hyperelastic behavior while the Bergstr?m-Boyce flow model is applied in the viscoplastic networks to capture the nonlinear viscous flow. The proposed constitutive model is implanted into the finite element software Abaqus with which, the multistep tensile relaxation test is simulated. The simulation result is satisfactorily consistent with experimental results, which verifies the effectiveness of the TN model. Finally, the simplified molding process of a tire tread is simulated, which further verifies the stability of the TN model.

Objective To investigate relationship between vitamin D level and season, sleep quality and anxiety and depression in patients with chronic insomnia. Methods Total 246 patients with chronic insomnia and treated in The First Hospital of Hebei Medical University from August 2020 to August 2022 were included. Serum 25⁃hydroxy vitamin D [25 (OH) D] levels were determined. Pittsburgh Sleep Quality Index (PSQI) was used to evaluate sleep quality, Hamilton Anxiety Rating Scale⁃14 (HAMA⁃14) to evaluate anxiety, and Hamilton Depression Rating Scale⁃24 (HAMD⁃24) to evaluate depression. Results The incidence of serum 25 (OH) D deficiency ( < 20 ng/ml) in chronic insomnia patients was higher than that in control group (χ2 = 78.202, P = 0.000), and serum 25 (OH) D level was lower than that in control group (Z = ⁃ 6.677, P = 0.000). According to the onset season, 246 chronic insomnia patients were divided into winter and spring group (n = 156) and summer and autumn group (n = 90). PSQI score (Z = ⁃ 2.694, P = 0.007), HAMA⁃14 total score (Z = ⁃ 2.166, P = 0.030), somatic anxiety score (Z = ⁃ 2.545, P = 0.011) and HAMD⁃24 score (Z = ⁃ 2.065, P = 0.039) in winter and spring group were higher than those in summer and autumn group. Serum 25 (OH) D level in winter and spring group was lower than that in summer and autumn group (Z = ⁃ 2.681, P = 0.007). According to PSQI score, 246 patients with chronic insomnia were divided into mild ⁃ moderate insomnia group (n = 114) and severe insomnia group (n = 132). In severe insomnia group, the proportion of female (χ2 = 10.733, P = 0.001), HAMA⁃14 total score (Z = ⁃ 4.633, P = 0.000), mental anxiety score (Z = ⁃ 5.273, P = 0.000) and physical anxiety score (Z = ⁃ 2.859, P = 0.004), and HAMD⁃24 score (Z = ⁃ 5.430, P = 0.000) were higher than those in the mild⁃moderate insomnia group, and serum 25 (OH) D level was lower than those in the mild⁃moderate insomnia group (Z = ⁃1.986, P = 0.047). Correlation analysis showed that serum 25 (OH) D was negatively correlated with PSQI score (r = ⁃ 0.331, P = 0.000), HAMA ⁃ 14 total score (r = ⁃ 0.178, P = 0.005) and HAMD ⁃ 24 score (r = ⁃ 0.142, P = 0.027). Conclusions Patients with chronic insomnia have lower vitamin D level, and patients with winter and spring onset have lower vitamin D level, worse sleep quality, and more severe anxiety, depression and somatization symptoms. Patients with worse sleep quality had lower vitamin D level, and more anxiety and depression. Vitamin D deficiency is associated with sleep quality and risk of anxiety and depression in patients with chronic insomnia.

Radiopharmaceuticals derived from targeted molecules labeled with radioiodine have always been the research hotspots in the field of nuclear medicine. Radioiodine labeling also has a clear application demand in pharmacokinetic research. Methods for radioiodine labeling include direct labeling method and indirect labeling method. Direct labeling method has the advantages of rapid reaction, simple operation and high radiochemical yield, but it has the problems of narrow scope of application and deiodination in vivo; and for the indirect method, although radioiodine labeled drugs shows good stability in vivo, it has the problems as complicated process and low radiochemical yield. With the purpose of providing reference for the development of radioiodine labeled drugs and isotope pharmacokinetics study, this paper introduced the research progress, application scope, advantages and disadvantages of radioiodine labeling methods, and prospected the development of radioiodine labeling methods.

Objective·To compare the pregnancy outcomes of infertile women with bilateral severe hydrosalpinx receiving neosalpingostomy or salpingectomy.Methods·The single-center prospective cohort study from 2005 to 2012 focused on pregnancy outcomes of infertile women aged 20‒40 years, with bilateral severe hydrosalpinx, undergoing bilateral neosalpingostomy or salpingectomy in International Peace Maternal and Child Health Hospital, Shanghai Jiao Tong University School of Medicine. The choice for treatment was based on a shared decision approach, and the participants were divided into the neosalpingostomy group and salpingectomy group. After registration of baseline characteristics, including age, birth place, reproductive history, preoperative hysterosalpingography results, surgical findings, and pregnancy outcomes, women were followed up on an annual basis until July 2020 for the occurrence of live birth by outpatient follow-up or telephone questionnaire. Intention-to-treat analysis and per-protocol analysis were applied to compare the pregnancy outcomes. Kaplan-Meier analysis and COX proportional hazard model were used to analyze the reproductive outcomes. In addition, subgroup analysis was performed based on age stratification. The main outcome measures were live birth rate, cumulative live birth rate, and factors affecting live birth. Secondary outcome measures included the mode of conception, time to live birth, biochemical pregnancy rate, clinical miscarriage rate, and ectopic pregnancy rate.Results·A total of 113 women were included in the analysis, 58 women underwent bilateral neosalpingostomy, and 55 women underwent bilateral salpingectomy. The study demonstrated that in infertile women with bilateral severe hydrosalpinx, bilateral salpingectomy achieved higher cumulative live birth rate than bilateral neosalpingostomy (76.36% vs 62.07, HR=2.18,95%CI 1.37‒3.45). In the neosalpingostomy group, 34.48% (20/58) live births were obtained after in vitro fertilization treatment, and 27.59% (16/58) live births were obtained through spontaneous conception which mainly occurred within 3 years after initial neosalpingostomy, while all live births in the salpingectomy group were obtained after assisted reproductive therapy. However, the risk of ectopic pregnancy was higher in the neosalpingostomy group than that in the salpingectomy group (20.69% vs 1.82%, P

Bovine β-Lactoglobulin (BLG) induces severe cow’s milk allergy. This research investigated the effect of ultrasound-assisted luteolin (LUT) treatment on the structure and allergenicity of BLG. The structure of the treated BLG was characterized by Fourier transform infrared (FTIR) spectroscopy, circular dichroism (CD) spectroscopy, ultraviolet (UV) absorption spectroscopy and fluorescence spectroscopy, and its allergenicity was evaluated by enzyme-linked immunosorbent assay (ELISA) and cell experiments. It was found that the major interaction force between BLG and LUT was hydrophobic interaction both before and after ultrasonic treatment. Ultrasound-assisted LUT treatment significantly altered the secondary and tertiary structures of BLG, and reduced the IgE-binding ability and the release of interleukin-6, interleukin-4 and histamine from KU812 cells. Therefore, ultrasound-assisted LUT treatment changes the conformational epitope of BLG, reducing its allergenicity, and the best effect can be achieved by secondary ultrasound-assisted LUT treatment.

Background Recent small subcortical infarct (RSSI) is one of the manifestations of lacunar infarction. It is a common brain disease and can lead to the clinical outcome of disability or dementia in many patients. However, the relationship of infarction burden and cognitive impairment with blood glucose fluctuation in type 2 diabetes mellitus (T2DM) patients with RSSI is not very clear. Objective To explore the correlation of blood glucose variability (GV) with infarction burden and cognitive impairment in T2DM patients with RSSI, and based on this, to build a risk prediction model. Methods A total of 140 patients with T2DM and RSSI who were treated in the Second Affiliated Hospital of Zhengzhou University from January 2021 to June 2022 were retrospectively selected. The basic clinical data of the patients were collected. The 72-hour continuous blood glucose monitoring was performed. The infarct burden was evaluated by the magnetic resonance imaging performance (the study subjects were divided into the high infarction burden group including 45 cases and the low infarction burden group including 95 cases according to the imaging performance). The cognitive function was evaluated by the Montreal Cognitive Assessment (MoCA). Spearman correlation analysis was used to explore the correlation between GV and cognitive function (MoCA score). Multivariate Logistic regression analysis was used to explore the influencing factors of infarction burden and cognitive dysfunction in T2DM patients with RSSI. The receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of GV on cognitive impairment in T2DM patients with RSSI, and the nomogram predictive model was constructed and the predictive value was analyzed. Results In terms of GV-related indicators, the high infarction burden group had higher standard deviation (SD) and percentage of coefficient of variation (%CV) and lower time in range (TIR) than the low infarction burden group, with statistically significant differences (P

With the continuous exploration and development of shale gas in China, the complex structure area has become an important direction for further exploration. The Longmaxi shale samples collected from complex structure area in Northeast Chongqing were conducted scanning electron microscopy, mercury intrusion, low-pressure gas adsorption, isothermal adsorption. This study systematically characterized the pore structure and adsorption capacity of Longmaxi shale in different tectonic belts, analyzed the influencing factors of pore structure and adsorption capacity, and revealed the action mechanism of tectonic deformation on pore structure and adsorption capacity. The results showed that ① OM pores are relatively developed in the Longmaxi shales collected from thrust slip belt and thrust fold belt, but not in the Longmaxi shale from imbricate thrust belt, where mineral-related pores and fractures are mainly developed. ② Micropores (50 nm) are developed in the Longmaxi shale in the thrust slip belt, while mesopores and macropores are relatively developed in the thrust fold belt and imbricate thrust belt. ③ The “excess” adsorption capacity of Longmaxi shale rapidly increases with the increased pressure, and slowly decreases after reaching the maximum (6−9 MPa), while the absolute adsorption capacity monotonously increases with the increased pressure. ④ The pore structure is mainly controlled by TOC (Total Organic Carbon) and clay mineral content, and the adsorption capacity is closely related to TOC and micropores. In addition, tectonic deformation can also affect the adsorption capacity by modifying the pore structure. This study has a very important guiding significance for the evaluation and development of shale gas resources in complex tectonic areas.

Ougan (Citrus Suavissima Hort. ex Tanaka) as a long history of edible and medicinal fruit, has a unique taste, and can clear heat, detoxify, eliminate phlegm and relieve cough. However, because of its slight bitterness, it has a strong regional consumption and is not widely accepted. This review focuses on the preparation technology and content analysis of nutritional and functional components in Ou orange, summarizes the research and development status of the processing products of ou orange, such as traditional "Gan er wen" and tangerine peel, as well as new Ougan enzyme, fruit vinegar and fruit wine, and points out the future research direction in the field of deep processing of ou orange.

Background The worldwide COVID-19 pandemic has turned into a global catastrophic public health crisis, and the conclusion about the risk factors of hospital death in COVID-19 patients is not uniform. Objective To explore risk factors of in-hospital death in patients with COVID-19 by a meta-analysis. Methods Case-control studies about risk factors of in-hospital death in COVID-19 patients were searched from databases of the Cochrane Library, ScienceDirect, PubMed, Medline, Wanfang Data, CNKI and CQVIP from inception to October 1, 2021. Literature screening, data extraction and methodological quality assessment were conducted. Meta-analysis was performed using Stata 15.1. Meta-regression was used to explore the potential sources of heterogeneity. Results Eighty studies were included which involving 405 157 cases〔349 923 were survivors (86.37%) , and 55 234 deaths (13.63%) 〕, that were rated as being of high quality by the Newcastle-Ottawa Scale. Meta-analysis showed that being male〔OR=1.49, 95%CI (1.41, 1.57) , P

General practice research focuses on a range of topics, such as patients' physical health and mental health, physicians' competencies and career motivation, quality of healthcare and physician-patient relationships and cooperation. However, these are not resolved well only using quantitative research which is still dominated in the field of general practice. In this case, qualitative method is often required, although it is considered to be subjective, and is mainly used to describe a phenomenon that is little known in a small sample. Mixed methods research, which incorporates qualitative and quantitative research and combines the advantages of both, can analyze specific problems more extensively and intensively, is suitable for studying complex problems, and for general practice research as an approach integrating clinical medicine and sociology. However, mixed methods research in general practice is still in its early phase in China, and the standardization of its design and implementation needs to be improved. For better elaborating the key points in the design and implementation of mixed methods research, we detailed a study using mixed methods, providing a reference for general practitioners to carry out mixed methods research.

Using multi-walled carbon nanotubes (MWCNTs) as a novel sorbent and a new special anionic chromatographic column for pesticide residues, an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the simultaneous direct determination of glufosinate ammonium and its metabolites 3-methylphosphino-propionic acid and N-acetylglufosinate ammonium in milk. The samples were extracted with methanol, cleaned up using MWCNTs, and degreased by high-speed centrifugation at low temperature. The analytes were separated on an Anionic Polar Pesticide (2.1 mm × 100 mm, 5 μm) column using a mobile phase containing 0.9% formic acid solution (A) and 0.9% formic acid solution-acetonitrile (B). The instrument was operated in the negative ion scanning mode with multiple reaction monitoring. Glufosinate ammonium was quantified by an internal standard method, and its two metabolites by an external standard method. The calibration curves for glufosinate ammonium and its two metabolites were linear in the concentration range of 1–50, 2–50 and 2–50 μg/L with correlation coefficient (R2) greater than 0.99. For these compounds, the limits of detection were 2.5, 5.0 and 5.0 μg/kg, and the limits of quantification were 5.0, 10.0 and 10.0 μg/kg, respectively. The recoveries ranged from 79.35% to 101.80%, with relative standard deviation (RSD) between 1.15% and 8.63%. The proposed method is characterized by simple pretreatment, stable chromatographic conditions, low impurity interference, high sensitivity and good accuracy, and is suitable for the determination of glufosinate ammonium and its metabolite residues in milk.

The ex-core nuclear instrument equipment consists of the source range detector, the start-up and work range detector and the refueling monitoring range detector in Tianwan nuclear power plant (NPP). The neutron flux density of the reactor is monitored by the refueling monitoring range detector, which is a temporary device，installed into the measurement tubes before refueling and dismounted after refueling manually. It will increase radiation risk to worker, prolong overhaul period and have an impact on the economic benefits due to installing and dismounting the refueling monitoring range detector. To cope with the deficiency of neutron flux density monitoring method during refueling in Tianwan NPP, an optimization scheme was investigated to replace the refueling monitoring range detector with the source range detector to complete the neutron flux density monitoring during refueling. How to calculate source range detector neutron counting rate exactly was critical to this scheme. Firstly, the neutron emission rate versus burnup of spent fuel assemblies with initial enrichment of 2.4%, 3.6%, 4.0% and 4.9% were calculated using the ORIGENS program, mainly considering the spontaneous fission neutron and (α, n) neutron. Secondly, based on the actual core structure，the axial distribution of the neutron emission rate and the neutron emission spectrum of the spent fuel assembly calculated by the ORIGENS program，a Monte Carlo program MCNP was used to simulate the calculation of the neutron flux density where the source range detector was located. Finally, the neutron counting rates of the source range detector were calculated with considering about the deviation coefficient K and the conservative factor B and compared with the experimental data. In this paper，the calculation of the neutron counting rates of the source range detector were performed according to the two core refueling methods of all-in and all-out and core feeding. The calculation results show that: 1) The neutron counting rate of the 6th channel source range detector is affected mostly by the spent fuel assembly located at (15, 24); 2) The neutron counting rate of the source range detector is 0.5 s-1 when the burnup of the spent fuel assembly near the source range detector reachs a certain one, and which is in good agreement with the measured value. According to the fuel management strategy of Tianwan NPP unit 3, the burnup of the spent fuel assembly near the source range detector will reach 44 000 MW·d·tU-1 since the third cycle, which will ensure the neutron counting rate meets the monitoring requirement during refueling. It shows that the method of the source range detector can be used for the monitoring of the neutron flux density replacing the monitoring range detector during refueling.

With the development of multi-source AC/DC distribution networks, DC fault detection technology has become the key to DC protection. Aiming at the characteristics of large fault current with a rapid rise and difficulty to extract fault features when distribution line faults occur in the DC part, a fault detection technology of AC/DC distribution network based on deep belief network (DBN) is proposed combining feature extraction in the time domain and frequency domain. By analyzing the characteristics of the fault equivalent circuit, Fourier transform and phase-mode transform are used to extract the frequency domain and time domain characteristics of the fault current and voltage signals as the input of DBN, and the Softmax classifier is used to output the fault pole selection and fault area identification results. An AC/DC distribution network model is built on PSCAD to test the algorithm. The simulation result shows that the proposed detection method still has high accuracy and the strong ability to tolerate noise under the influence of line-distributed capacitance and control strategy. The further algorithm comparison experiment shows that the necessary combination of fault feature extraction and effective deep learning model training can complete the complex fault detection.

Wear is one of the main failure forms of metal parts， and the surface coating technology is one of the important methods to protect metals from wear. TiC-TiB2 dual-phase composite wear-resistant ceramic coating is widely used as a protective coating for material surface due to dual advantages of carbide and boride ceramics，such as higher hardness and better wear and corrosion resistance. In this paper，the research progress of in-situ TiC-TiB2 composite coating was reviewed from two aspects: preparation method and main metal binders of TiC-TiB2 coating.The advantages and disadvantages of different preparation methods for TiC-TiB2 coating were compared， and the problems and possible solutions in practical applications were referred. The synthesis mechanisms and the reasons for improving the performance of TiC-TiB2 coating after adding different metal binders were summarized. The advantages and disadvantages of various metal binders in actual applications were analyzed. Finally， the future optimization directions and urgent problems of the preparation process of TiC-TiB2coating were pointed out.

Aiming at the situation of surface coating spalling of water pipeline in a hydropower plant in South China due to extremely humid operating environment， the corrosion mechanism of carbon steel pipelines and the influence of different impressed currents on the corrosion of pipelines under the combined action of impressed current cathodic protection and coating were studied by using the simulation experiment device with the application of both impressed current cathodic protection and coating. Results showed that at the initial stage of corrosion， the more negative the cathodic protection potential applied to the sample，the lower the corrosion rate of the sample. However，with the extension of the corrosion time， the corrosion rate of the sample at the normal cathodic protection potential (-1.20 V≤E≤-0.85 V) (vs SCE， the same below) was the lowest after 60 days of corrosion， and the excessively negative cathodic protection potential (≤-1.20 V) would cause cathodic stripping of the surface coating on the sample. In addition，under normal (-1.20 V≤E≤-0.85 V) and over-protection (≤-1.20 V) cathodic protection potential， the corrosion products of samples were relatively compact and flat. By contrast， under the conditions of no cathodic protection and under-protected cathodic protection potential (≥-0.85 V)， the corrosion products of the samples were fine and loose particles.

In order to explore the law of proppant migration and placement under clean fracturing fluid, an Euler multiphase flow model was established through FLUENT numerical simulation software based on computational fluid dynamics(CFD). The model takes into account the rheological properties of fracturing fluid and the friction and collision of proppant particles. The influence of proppant size, density and sand ratio on the shape of the sand dike is studied by using the equilibrium height and equilibrium time as the characterization parameters. The results show that the clean fracturing fluid is easier to carry the proppant to the depth of the fracture than the conventional fracturing fluid, so that the proppant is evenly distributed in the fracture; proppant with large particle size and high density can easily settle in the fracture opening under the carrying of the clean fracturing fluid, while proppant with small particle size and low density can improve the sand carrying capacity of fracturing fluid and transport proppant into deep fracture. Increasing sand ratio in a certain range can improve the height and laying area of the sand dike, but excessive sand ratio has little effect on the shape of the proppant sand dike and is easy to cause sand blockage.

As an indispensable component in an active noise control system, the working states of the secondary sound sources affect directly noise reduction and the robustness of the system. Therefore, it is very crucial to detect the working states of the secondary sound sources in the process of active control in real time. In this study, a real-time fault detection method for secondary sound sources during the process of active control is presented, and the corresponding detection algorithm is numerically given and experimentally verified. By collecting the input voltage and output current of the speaker unit, the sound quality factor is calculated to comprehensively judge the working state of the secondary sound sources. The simulation and experimental results show that the present method is simple and has low computational cost, can accurately reflect accurately the working states of the secondary sound sources in real time, and provides a basis for judging the operation of the active noise control system.

Objective To determine the differences in the expression of serum complement （C） and IL-25 in systemic lupus erythematosus （SLE） involved with single or multi-organ systems， and analyze the correlation between serum C3， C4， CH50， IL-25， C-reactive protein （CRP） and anti-dsDNA antibody. Methods A total of 151 SLE patients were included in this study. According to the organ involvement status， all patients were divided into the SLE alone （n = 58）， SLE complicated with single organ injury （n = 67， 51 cases of lupus nephritis， 13 cases of blood system injury and 3 cases of other organ injury）， and SLE complicated with multi-organ injury groups （n = 26， 25 cases of lupus nephritis complicated with other organ injury and 1 blood system complicated with brain injury）. The levels of serum C3， C4， CH50， IL-25 and CRP， and positive rate of anti-dsDNA antibody were detected among three groups. The correlation among these indexes was analyzed. Results There was no significant difference in the C4， CH50， IL-25 and CRP levels among three groups. There were significant differences in the C3 level and positive rate of anti-dsDNA antibody among three groups （all P < 0.05）. In the multi-organ injury group， C3 level was significantly lower， whereas positive rate of anti-dsDNA antibody was significantly higher compared with those in the remaining two groups （all P < 0.017）. Spearman rank correlation test indicated that C3 level was positively correlated with C4 （rs = 0.73， P < 0.001） and CH50 levels （rs = 0.81， P < 0.01）， whereas negatively correlated with IL-25 level （rs = -0.14， P < 0.001）. Conclusions In SLE patients with multi-organ involvement， serum C3 level is significantly decreased， whereas positive rate of anti-dsDNA antibody is significantly increased. Detection of serum complement levels is of clinical significance for the prediction of multi-organ injury in SLE patients.

In view of the problem of water inrush from coal seam floor in China, the application effect of water inrush prevention measures of coal seam floor in recent years, such as the research on the mechanism of water inrush from coal seam floor under various conditions of different geological structures and high aquifer water pressure in China, and the widely used floor grouting reinforcement technology, the establishment of fault waterproof coal pillar and the drainage and pressure reduction before mining are summaried and analyzed, the shortcomings of the research on water inrush from coal seam floor are pointed out. The prospect of large mining depth, complexity, low cost, green, high efficiency and intelligent control of water inrush from coal seam floor is proposed.

Tiger nut (Cyperus esculentus L., TN), is a perennial sedge plant of the family Salicaceae, native to Africa, and has been introduced to China as an emerging crop that integrates food, oil, pasture and forage. The tubers are not only nutritious, but also have medical health functions such as lowering blood pressure, blood lipids and cholesterol. In this paper, the latest research progress of processing non-oil products of Olea europaea was described from several fields, such as Olea europaea staple food products, Olea europaea beverage products, Olea europaea fermented products, and other products. The future of processing development was also outlined to provide reference for the exploitation and utilization of Olea europaea tubers and its oil extraction by-products.

Spent nuclear fuel reprocessing is the key step of the nuclear fuel cycle. It also restricts the sustainable development of nuclear power. With the help of external neutron source in an accelerator driven advanced nuclear energy system(ADANES), spent nuclear fuel reprocessing only needs to remove some volatile fission products and neutron poisons, such as rare elements. Moreover, it is not necessary to separate the long-lived minor actinides Np, Am and Cm finely. These minor actinides can be refabricated as new nuclear fuels together with uranium dioxide for burn, transmutation, breeding, and power production in the accelerator driven advanced nuclear energy system. Based on this, our group proposed a technical route for spent nuclear fuel reprocessing and regeneration of accelerator driven advanced nuclear energy system, including high-temperature oxidation pulverization and volatilization, selective dissolution separation, and fuel regeneration. The recent research of our group is summarized, which has a great significance for implementation of accelerator driven advanced nuclear energy system.

In order to accurately grasp the fire hazard performance of coal mine cable, the light transmittance of coal mine cable fire smoke, ignition time, peak heat release rate(PHRR), total heat release(THR), peak smoke generation rate(PSPR) and total smoke production(TSP) under different thermal radiation intensity were measured by NBS smoke density test box and cone calorimeter, and then the fire hazard of coal mine cable was analyzed. The results show that the light transmission rate decreases rapidly, it is basically reduced to 0 at 130 s. Compared with coal mine cable at 30 kW/m2, the PSPR, TSP, and arrival time of PSPR of coal mine cable at 35 kW/m2 and 40 kW/m2 are significantly reduced. With the increase of thermal radiation intensity, the PHRR of coal mine cable increased. The THR at 40 kW/m2 is 1.99 and 2.43 times higher than that at 30 kW/m2 and 35 kW/m2. Besides, the greater the thermal radiation power is, the greater the fire risk of coal mine cable is.

With the development of intelligent technology and equipment in coal mine, it gets a lot of results in the intelligent ventilation system. However, there are many deficiencies in the catastrophic ventilation system. However, there are few studies on the management of ventilation system after disasters. As one of the means to prevent and control fresh air side disasters, the research on technology and equipment of ventilation system should be strengthened. Through the study of air counter technology in 3105 fully mechanized caving face of a coal mine, the wind control technology of main inlet roadway disaster and working face air inlet drift disaster is obtained. According to the wind control technology, the technical requirements of hardware such as air door, wind window, wind measurement, environmental acquisition sensor, voice broadcast and disaster avoidance command are analyzed, which provides technical and hardware equipment support for the ventilation system of similar mine working face.

Aiming at the problems of poor real-time ventilation monitoring, lack of remote regulation of ventilation facilities, complex and inefficient air volume regulation process in Hulusu Coal Mine, in order to realize the controllability, visualization and intelligence of air volume regulation, the construction of intelligent ventilation facilities such as accurate air volume measurement device and remote regulation air window, including ultrasonic wind speed sensor and full section wind measuring station, has been carried out in terms of functions, the integrated ventilation intelligent control system of Hulusu Coal Mine is designed and constructed, which realizes the real-time synchronous monitoring of mine air volume, remote regulation of air volume and fault diagnosis of ventilation system, and has the functions of ventilation equipment management, data management, early warning management, authority management and remote control.

The resistance temperature characteristics and thermal stability of graphite based flexible grounding materials were studied. With the method of current heating and constant temperature protection, the resistance of grounding body at each temperature was measured by voltammetry, and the average resistance temperature coefficient was derived. With the resistance temperature characteristic parameters of the grounding body obtained from the experiment, the maximum temperature rise of the graphite based flexible grounding body under the power frequency grounding fault current and lightning impulse current was calculated iteratively, which is verified by the calculation of the thermal stability coefficient. The experimental results show that the graphite based flexible grounding body has a negative temperature coefficient. When the maximum allowable service temperature of the graphite based flexible grounding body is 450 ℃, the maximum allowable current under 0.5 s power frequency current is about 1.4 kA, which is 8/20 μs the maximum allowable passing current amplitude of graphite based flexible grounding body under the impact of high frequency lightning current is 287.9 kA.

To further understand the film - forming properties of SEBS (styrene - ethylene - butylene - styrene) resins commonly used in solvent - based strippable coatings, the effects of paint film thickness, plasticizer usage and resin weight average molecular weight on the film - forming properties of SEBS resins were investigated respectively according to relevant national standards. Results showed that the cracking problem arose during the film formation of SEBS resins was caused by the internal stress resulting from the shrinkage of the paint film. Hence, a SEBS resin with a weight average molecular weight less than 140 000 shall be selected as far as possible when preparing a coating with SEBS resin.

Background Community-acquired pneumonia (CAP) is one of the common infectious diseases with high morbidity and heavy disease burden. Despite the continuous advancement of diagnostic technology and the launch of new antimicrobial drugs, the morbidity and mortality of CAP are still high. The clinical research of Shufeng Jiedu capsules in the adjuvant treatment of CAP is increasing, but there is still a lack of systematic review and meta-analysis. Objective To systematically evaluate the efficacy and safety of Shufeng Jiedu capsules in the treatment of CAP. Methods Randomized controlled trials (RCTs) about Shufeng Jiedu capsules in the treatment of CAP was retrieved in CNKI, Wanfang Data, VIP, SinoMed, PubMed, Cochrane Library and EMBase from inception to November 2021 by computer. The control group was treated with routine western medicine, and the experimental group was treated with Shufeng Jiedu capsules orally on the basis of the control group. The retrieval time was from the establishment of the database to November 2021. RevMan 5.3 software was used for data analysis, and GRADE criteria were used to evaluate the level of evidence for the outcome indicators. Results A total of 13 studies with 1 355 patients were included. The results of meta-analysis showed that the cure rate of the test group〔RR=1.49, 95%CI (1.28, 1.74), P

With the continuous expansion of power grid scale, the phenomenon of subsynchronous oscillation caused by series compensated long-distance transmission system occurs frequently. Therefore, in order to analyze the deep reasons for the instability of the series compensated transmission system, based on the open-loop mode resonance theory, an open-loop mode resonance analysis method is proposed to analyze the subsynchronous oscillation caused by the series compensated transmission line. The small signal model of the external series compensated transmission line of permanent magnet synchronous generator (PMSG) farm is established, and the dynamic interaction between the series compensated line and the PMSG farm is studied through the open-loop mode resonance analysis method. The results show that the closed-loop stability of the system decreases when the open-loop subsynchronous oscillation mode dominated by series compensation is close to the open-loop subsynchronous oscillation mode dominated by wind farm in the complex plane. Using residual theory can successfully predict the position of closed-loop mode under the condition of open-loop mode resonance, while changing PMSG parameters or adjusting series compensation can avoid the occurrence of dynamic interaction. The correctness of the above theoretical analysis is verified by an example system in this paper. It is proved that there is a certain risk of instability when the PMSG farm transmits power through the series compensation transmission line, which can provide a reference for the parameter setting of the series compensation transmission system to a certain extent.

In recent years, sub-synchronous oscillation incidents have been reported to happen globally, which seriously threatens the safe and stable operation of the power system. As the capacity of a single wind turbine generator is small, a wind farm with tens even hundreds of wind turbine generators makes the order of the model of the wind farm high with the wind turbine generators complex coupled with each other. Reasonable and effective equivalent modeling of the wind farm is the basis for the study on the reasons, characteristics and suppression of the oscillations in the wind power integrated power system. In this paper, the advantages and disadvantages of the existing relatively thorough methods for wind farm equivalent modeling is analyzed based on the recognition of the reasons for the sub-synchronous oscillations in the wind power integrated power system. Then the issues in the field of equivalent modeling of the wind farm that need to be further studied are summarized, hoping to provide references for the future study of small-signal dynamic equivalence of a wind power collecting system and sub-synchronous oscillations of the wind power integrated power system.

In this work, various latest design ideas and research methods regarding ZrN series ceramic hard films were summarized, the advantages and disadvantages of such research methods were examined, and the research direction of the film was prospected. The influence of advanced preparation methods and process parameters on coating were discussed based on the analysis of ZrN film’s physical and chemical properties. In addtion, the structure, composition, corrosion resistance and wear resistance of gradient films and multilayer films based on the ZrN phase were analyzed and discussed. It pointed out that the multilayer and gradient ceramic films had properties that a single ZrN phase film could not realize, and thus they would still be the research direction of the ZrN phase system ceramic hard film in the future.

Aiming at the corrosion and abrasion of the inner wall of the steam pipes caused by the piston wear under the high temperature of 150 ℃, based on the solvent-free epoxy resin system, a temperature-resistant and wear-resistant epoxy coating applicable to the inner wall of steam pipes with good comprehensive performance was developed through the selection of filler, additives, and the design of formula. The coating adopted a resin system modified by blending E-031 alicyclic epoxy resin and J-129 phenolic epoxy resin, and selected PTFE as the lubricating filler. Moreover, the effect of its different particle size and dosage on the wear resistance of the coating was researched, and it could be found that the wear resistance of the coating was better when the amount of PTFE powder with a particle size of 2 μm was 7%(mass fraction, the same below). Meanwhile, through the screening of silane coupling agent and the research of performance, the optimal dosage of KH-560 was determined as 1.5%, and finally a solvent-free, temperature-resistant and wear-resistant epoxy coating with good comprehensive performance meeting the use requirements was prepared.

Drag-reduction and fuel conservation,one of the significant benefits of active center of gravity(CG)control function,plays an important role in iterative and optimal design of function scheme. Based on its principle and scheme,the active CG control function of a certain aircraft is modeled,coupling with flight control system model,automatic flight control system model,fuel system model,aerodynamic model,engine model and aircraft 6-DOF(degree of freedom)model,with the consideration of effect of CG variations induced by fuel consumption. At the given altitude and Mach number,the benefits of active CG control function are estimated,through setting different target CG positions. The results show that it can bring considerable benefits to aircraft with the application of active CG control technology,especially,the more backward the target CG is,the more obvious benefits will be generated. The Mach number has an impact on the benefits of the function. Under the same conditions,the larger the Mach number is,the greater the return will be.

To explore the hazard zone of coal spontaneous combustion in the adiacent goaf at different stages of the roadway driving face, the 2202 working face and the 2201 adjacent goaf of Yingpanhao Coal Mine were taken as examples. The large-scale experiment was conducted to analyze the coal spontaneous combustion limit parameters of the 2201 goaf. The conditions for identifying the hazard zone of coal spontaneous combustion in the adjacent goaf were proposed. Monitoring the gas concentration and temperature in 2201 adjcent goaf by the drilling holes through coal pillar, and the numerical simulation was conducted to study the oxygen concentration distribution in 2201 adjcent goaf, and the hazard zone of coal spontaneous combustion in the adjacent goaf was obtained. The results show that during the mining period of the 2202 working face, the coal pillar was broken by the stress concentration, and the oxygen volume fraction of the adjacent goaf was in the range of 10.1% to 13.8%. The oxygen volume fraction of the adjacent goaf before the stop mining period was between 10.3% and 15%. During the mining period, a narrow area on the coal pillar side with width 55 m from the front 45 m and behind 119 m of 2202 working face in the adjacent goaf was the coal spontaneous combustion hazard zone. Before the stop mining period, a narrow area on the coal pillar side with width 42 m from the front 63 m and behind 107 m of 2202 working face in the adjcent goaf was in an oxidizing environment.

The implementation of targeted therapies for breast cancer has been a challenge. Saikosaponin D (SsD), a triterpene saponin derived from Bupleurum, exhibits potential therapeutic properties for cancer therapy. Here, the role of SsD in broad antiproliferation effects in breast cancer was investigated, and the SsD pharmaceutical efficacy was evaluated by metabolomics analysis. Low (0.4 mg/kg) and high (2.0 mg/kg) concentrations of SsDs were used to treat breast cancer tumors in mice by intraperitoneal injection. Blood samples of mice were collected and the serum samples were extracted after SsD administration for different days. Subsequently, the serum samples were analyzed by ultra-high performance liquid chromatography tandem Orbitrap mass spectrometry (UPLC-Orbitrap MS). According to the “80% rule”, UPLC-Orbitrap MS data were processed and proper ions were screened out for further analysis. Statistical methods including one-way analysis of variance (One-way ANOVA), principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were performed to cross validate the reasonable and accuracy of the models. Representational metabolite ions present significant differences acquired by comparison within/between control group, SsD low concentration group and SsD high concentration group. The results of animal survival experiments demonstrated that SsD had obvious therapeutic effect on tumor. Mice treated with low and high concentrations of SsD showed 60% and 80% survival rate, respectively, with a significant increase in survival compared to untreated control mice. Metabonomic results showed that 12 target metabolite ions including pipecolic acid, N-acryloylglycine, 3-methyleneindolenine, L-kynurenine, phenylethylamine, DL-2-aminooctanoic acid, N (6)-methyllysine, indoleacetaldehyde, 3-methylhistamine, hexanoylglycine, hypoxanthine and hexanoylcarnitine were obtained by intra-group (in control group) screening. The signal intensities of these 12 ions changed significantly in the process of tumor growth, which provided theoretical basis for the study of tumor development and evolution. Meanwhile, 7 important metabolite ions including 3-methylene-indolenine, phenylethylamine, pipecolic acid, L-kynurenine, indoleacetaldehyde, 5-acetylamino-6-formylamino-3-methyluracil and proline betaine were obtained by analyzing inter-group data (compared among three groups), and the first 5 metabolite ions were overlapped with the ions in the list of intra-group screening. Moreover, the biological significances of the selected ions with significant difference were investigated, and two highly correlated manifested metabolic pathways including amino acid metabolism and nucleotide metabolism were discussed. Overall, the results derived from intra-group metabolomic analysis were highly correlated with the inter-group results, and the metabolites along the relevant pathways deserve further attention. This study provides a practical strategy for targeting metabolic analysis using natural product to improve the survival of patients with breast cancer.

ObjectiveTo review the strengths and limitations of the development of general practice in China during the last decade (2010—2020) and to assess the opportunities and challenges for its future development.MethodsData were collected from statistic reports, journal articles and official policies and guidelines regarding general practice development in China from 2010—2020. Donabedian model was applied to examine and assess the quality of essential general practice services in China. SWOT analysis was used to identify internal and external determinants of general practice development in China.Results(1) Structural quality of general practice: the ten-year policies about general practice development were a continuation of the past relevant policies in essence but with developments, with highlights on continuous construction of general practice workforce and discipline, tiered diagnosis and treatment and regional medical consortium, but relevant fiscal and management policies still need improvements. The number of general medical workers has increased rapidly, while the lion's share of them are still allocated at tertiary hospitals. Full-time equivalent is suggested to be used to predict the staffing and assess the performance of these workers. The number of community health centres showed a steady increase, but its growth rate was still slower than that of hospital facilities. Relevant health economics data need to be further supplemented. (2) Process quality of general practice: in 2020, there were 2.045 billion visits in community health centers (stations) and township health centers, that is, 1.5 visits per person per year on average. There was a significant development when found only 1 visit per person per year for primary care in 2010. However, the frequency of visits for primary care was still lower than that of visiting hospital-based outpatients (an average of 2.7 visits per person per year) . The COVID-19 pandemic had a significant impact on community health services/general medical services, and the number of outpatient visits dropped by about 20%. The number of general practice research articles reached a peak in 2018, mainly focusing on bi-directional referrals, tiered diagnosis and treatment, general practitioners (GPs) /family doctors, general medicine, community health services, chronic disease management (especially hypertension and diabetes) , and analysis of factors associated with aspects involved in general medical services. General practice research is expected to provide more support for developing innovative and critical thoughts, more practice-based evidence for clinical services, and more assistance for service quality and patient outcomes improvement as the discipline advances. (3) Results of implementing general medical services: there is no sufficient evidence on the influence of general medical services on people's health. The experiences and views of people including healthy individuals and patients indicated that those receiving general medical services or contracted family doctor services perceived positive experience and expressed high satisfaction, but perceptions and views of general population in the community toward general medical services need to be explored. GPs' own experience and opinions on general practice were quite different. Gender, age, professional title, urban and rural areas, and geographical location may be associated with their experience and job satisfaction. There may be instability in the general practice workforce, mainly due to personal income, workload and time pressure. (4) The major strengths of developing general practice in China are as follows: strong policy-based promotion and government leadership; rapidly constructing and developing GPs teams owing to the excellent resource allocating ability shown by the centralized system from central to all local governments; significantly enhanced general practice education and training systems; increased core professionals as general practice educators and trainers; special development of general practice characterized by the integration of medical sciences and Chinese traditional humanistic theories. (5) The development of general practice in China has been facing limitations similar to those in other countries. Besides that, its special limitations include late development of the discipline, unsatisfactory quality of workforce, high work pressure and high prevalence of burnout in the workforce, as well as impact of generation gap on education and practice among GPs. In addition, the relation between specialists and GPs is on transition of from undifferentiated attachment to self-recognised uniquity, and further seeking transdisciplinary. The teaching competences of GPs teachers, especially those teaching community and clinical care, are inadequate. GPs team building and management need to advance from the formation to the storming and performing phases. (6) Opportunities for further development of general practice in China include strategies for achieving the goals of Healthy China, and an all-round well-off society, the important role of primary health care in sustainable development and universal health coverage reaffirmed by the Declaration of Astana, as well as significantly improved health literacy of people. (7) Challenges for the development of general practice in China include population ageing, and aging-related changes in burden of disease and socio-economic status, the aging and dynamic changes of GPs human resources, the variation of urban and rural areas and regional differences, and the inverted pyramid structure of allocation of medical and health resources (namely, the largest part is allocated to tertiary care while the smallest to primary care) . Relevant recommendations to address these challenges comprise strengthening the advocacy of the development of general practice services, establishing a wide-ranging community collaborative network, and developing general practice professional organizations.ConclusionThe development of general practice in China is advancing, which is manifested as rapidly increased number of general medical workers, strong government promotion, quickly improved accessibility of essential medical services, and notably increased utilization rate of primary care services. However, the development is facing challenges, such as high discipline and social expectations regarding general practice, instability in the workforce due to high work pressure of the knowledge- and labor-intensive job, GPs' insufficient recognition of their self-identity, and unclear status of financial funding for general practice development. Given that there are unprecedented favorable conditions for general practice development, medical industries and general medical workers are suggested to make efforts to turn challenges into opportunities to develop general medical services, thereby universal health outcomes will be improved.