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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

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.

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

ObjectiveTo investigate the ability of combined baseline serum markers, i.e., HBV DNA, HBV RNA, HBsAg, and HBcrAg, to predict HBeAg seroconversion in patients with HBeAg-positive chronic hepatitis B (CHB) treated by nucleos(t)ide analogues. MethodsA retrospective analysis was performed for 83 HBeAg-positive patients selected as subjects from the prospective CHB follow-up cohort established by Difficult & Complicated Liver Diseases and Artificial Liver Center, Beijing YouAn Hospital, Capital Medical University, from June 2007 to July 2008, and the baseline serum levels of HBV DNA, HBV RNA, HBsAg, and HBcrAg were analyzed. The t-test or the Mann-Whitney U test was used for comparison of continuous data between two groups, and the chi-square test was used for comparison of categorical data between two groups. The Spearman method was used for correlation analysis. A Cox regression model was established to calculate HBeAg seroconversion prediction score, and the time-dependent receiver operating characteristic curve was used to evaluate the ability of combined markers in predicting HBeAg seroconversion. The Kaplan-Meier method was used to calculate cumulative seroconversion rate in each group, and the Log-rank test was used for comparison between groups. ResultsFor the 83 HBeAg-positive patients, the median follow-up time was 108 months, and 44.58%(37/83) of these patients achieved HBeAg seroconversion. Compared with the non-seroconversion group, the HBeAg seroconversion group had significantly lower baseline serum levels of HBV DNA ［6.23(1.99-9.28) log10IU/mL vs 7.69(2.05-8.96) log10IU/mL, Z=-2.345, P=0019］ and HBV RNA ［4.81(1.40-7.53) log10copies/mL vs 6.22(2.00-8.49) log10copies/mL, Z=-1.702, P=0010］, and there were no significant differences in the levels of HBsAg and HBcrAg between the two groups (P＞0.05). The Cox regression equation constructed based on the above serum markers showed a median score of 0.95(range 0.37-345) for predicting HBeAg seroconversion. In the total population, the combined score was negatively correlated with HBsAg, HBV DNA, HBV RNA, and HBcrAg (r=-0.697, -0.787, -0.990, and -0.819, all P＜0.001). Based on the median prediction score, the patients were divided into high HBeAg seroconversion group and low HBeAg seroconversion group; as for the prediction of HBeAg seroconversion rate at 36, 60, and 84 months, the high HBeAg seroconversion group had a seroconversion rate of 43.90%, 51.20%, and 63.10%, respectively, while the low HBeAg seroconversion group had a seroconversion rate of 9.60%, 17.00%, and 19.8%, respectively, and there was a significant difference between the two groups (χ2=11.6, P＜0.001). ConclusionThe combined prediction score based on baseline serum HBV markers can predict HBeAg seroconversion in CHB patients treated by nucleos(t)ide analogues.

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.

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.

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.

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.

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.

ObjectiveTo investigate the consistency between Shengxiang (S) and Xinbo (X) real-time PCR methods in the quantification of HBV RNA. MethodsIn the prospective follow-up cohort of 108 chronic hepatitis B (CHB) patients established from July 2007 to August 2008, 20 patients with HBeAg seroconversion were selected, and 20 patients without seroconversion were selected by propensity score matching at a ratio of 1∶1. The two quantification methods from S and X companies were used, and a retrospective analysis was performed for HBV RNA in serum samples at baseline and weeks 12, 24, and 48. The paired t-test was used for comparison of normally distributed continuous data between groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between groups; the chi-square test was used for comparison of categorical data. The Pearson correlation coefficient, intraclass correlation coefficient (ICC), and the Bland-Altman method were used to evaluate the consistency of the two quantification methods. ResultsA total of 132 serum samples were tested by S reagent, and 154 were tested by X reagent; the detection rate of HBV RNA was 100% by both reagents. A total of 131 serum samples were tested by both reagents, with 34 samples at baseline and 29, 35, and 33 samples, respectively, at weeks 12, 24, and 48 of follow-up; at these four time points, the HBV RNA quantification data detected by X reagent were significantly higher than those detected by S reagent (5.75±1.64/5.43±1.73/5.13±1.54/4.76±1.55 log10 copies/mL vs 4.80±1.48/4.52±1.53/4.10±1.50/3.92±143 log10 copies/mL, t=8.348, t=5.341, Z=-5.086, Z=-4.762, all P＜0.001). The correlation analysis of the two methods showed a Pearson correlation coefficient of 0.915 (95% confidence interval ［CI］: 0.836-0.957) and an ICC of 0.771(95%CI: -0.021 to 0.931) at baseline, a Pearson correlation coefficient of 0.849(95%CI: 0.701-0.927) and an ICC of 0.733(95%CI: 0.138-0.902) at week 12, a Pearson correlation coefficient of 0.951(95%CI: 0.905-0.975) and an ICC of 0.776(95%CI: -0.058 to 0942) at week 24, and a Pearson correlation coefficient of 0.933(95%CI: 0.867-0.967) and an ICC of 0.804(95%CI: -0.014 to 0944) at week 48 (all P＜0.05). The Bland-Altman analysis showed that the difference of 96.18%(126/131) samples tested by the two methods was within the mean difference±1.96 standard deviation. ConclusionHBV RNA quantification by X reagent is higher than that by S reagent, while the two real-time PCR quantification methods show a good consistency in CHB patients with HBeAg seroconversion and those without seroconversion.

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.

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.

Background With the deepening of health care reform in China, primary care and general practice researches have developed rapidly in recent years, and the number of papers published has increased rapidly. Objective Summarize and analyze the scientific research papers published in the field of primary care and general practice in China in 2021, explore the characteristics in the number of papers published, journals published, regions, institutions, research categories, research methods, and the number of authors. Methods Based on the disciplinary definition of the research concepts, themes and methods in this field, combining scoping review methods and bibliometric techniques, scientific research papers published by researchers in Chinese scientific research institutions in 2021 included in the CNKI, Wanfang, PubMed, and Web of Science database were retried, induced and analyzed. In this paper, combined with the scope review method and bibliometric technology, a systematic search and quantitative analysis were carried out on scientific research papers in the fields of primary care and general practice published by researchers in Chinese scientific research institutions in 2021 included in the CNKI, Wanfang, PubMed, and Web of Science databases. Results There are 3 122 original research papers published in the fields of primary care and general practice in China in 2021. The number of papers published by primary care institutions accounted for 57.69%, but most of the papers were completed by a single authoramong such institutions. Papers published by the eastern primary care institutions accounted for 80.12%. The research category is dominated by clinical research (58.23%) and health services researches (27.07%) , the co-occurrence analysis of keywords by VOSviewer shows that the research themes focus on "chronic disease management" and "contracted family doctor services", these papers mostly used randomized controlled trials (40.87%) and cross-sectional survey studies (36.71%) in research methods. The vast majority of papers in primary care and general practice field are published in non-core and non-SCI/SSCI journals (76.75%) , and only 6.98% of papers are published in SCI/SSCI journals. Conclusion The productivity level of primary care and general practice research in China has now reached the highest level in the world, of which the primary care institutions in the eastern region have made major contributions. The research topics in the primary care and general practice field are close to institutional practice and national health policy. However, there are still a series of problems and challenges in this field, such as the lack of cooperation among researchers in primary care institutions, the large number of studies using randomized controlled trial methods may have problems such as quality concerns and low recognition of research in this field in China by international SCI/SSCI journals.

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.

Established the double cold expansion simulation model, and investigated the effects of surface micromorphology characteristics on the fatigue performance of double cold expanded holes. The double cold expansion process and fatigue life of the strengthened holes was simulated by using ABAQUS and MSC. Fatigue software. The hole wall element was selected, and the surface micro-profile of the hole wall was represented as the semi-ellips micro-notches. The S-N curve of the material is modified by effective stress concentration factor Kf, and investigated the effects of surface micro-profile on the fatigue performance of double cold expanded holes.The results show that there existed compressive residual stress layer on the hole wall after the double cold expansion process, and the fatigue life of the expanded sample was increased. With the increasing of the number of micro-notches in the hole wall, the stress concentration factor can be alleviated effectively, and stress concentration factor Kt is positively correlated with the depth-width ratio b/a and the distance-width ratio d/（2a）. The double cold expansion process can reduce the surface roughness of the hole wall by 21%～49%, which can effectively alleviate the notch stress concentration and improve the fatigue performance of the hole.

As the international competitiveness of China’s manufacturing industry continues to improve, the manufacturing industry of China is developing toward a high-quality pattern that pursues quality and efficiency. Hence, constructing a standards system for the manufacturing industry becomes critical for upgrading and internationalizing China’s manufacturing industry as well as commercializing scientific research achievements of the industry. In this article, we summarize the development trends of the standards system for manufacturing, and study the construction of standards systems by focusing on four key areas: equipment manufacturing, new materials, new-generation information technology, and consumer goods; the frameworks, ideas, and key tasks of the standards systems for these areas are clarified. Furthermore, to promote the quality of China’s manufacturing industry, future focus should be laid on standards system research, standards application, standards management mechanism, and international standardization.

To address the current problems of insufficient vehicle detection accuracy and slow detection speed in complex traffic monitoring scenarios, a lightweight vehicle detection algorithm based on YOLOv8 model is proposed. Firstly, FasterNet is used to replace the backbone feature extraction network of YOLOv8, which reduces redundant computation and memory access, and improves the detection accuracy and inference speed of the model.Secondly, the SimAM attention module is added to the Backbone and Neck sections, which enhances the important features of the target vehicles without increasing the original network parameters, and improves the feature fusion capability. Then, to address the problem of poor detection of small-sized vehicles under dense traffic flow, a small target detection head is added to better capture the features and contextual information of small-sized vehicles. Finally, Wise- IoU, which can adaptively adjust the weight coefficients, is used as the loss function of the improved model, which enhances the regression performance of the bounding box and the robustness of the detection.The experimental results on the UA-DETRAC dataset show that compared with the original model, the improved method in this paper is able to achieve better detection accuracy and speed in the traffic monitoring system, with the mAP and FPS improved by 3.06 percengtage points and 3.36%, respectively, which effectively improves the problem of the poor detection of small-target vehicles in the complex traffic scenarios, and achieves a good balance between accuracy and speed. [ABSTRACT FROM AUTHOR]

To study the further evolution characteristics of the fracture plane or structural plane after rock failure, the granite was chosen and prepared as double penetration crack samples, and the friction sliding tests were conducted using twin-shear model.During the tests, the CCD camera was used to record the speckle images, and the digital speckle method was used to analyze the evolution characteristics of horizontal displacement field, vertical displacement and horizontal displacement in the process of friction sliding.The results show that: ① The major role in displacement evolution has changed from confining pressure to a combination of confining pressure and shear stress at the stage of slow growth in shear stress.The displacement evolution is dominated by shear stress at the stage of linear growth in shear stress.The increase and decrease of interface occlusal degree and horizontal alternate displacement can be used as precursors of rock interface friction slip.② The appearance and disappearance of the flow around the horizontal displacement field are the precursors of the local and global slip of the specimen, respectively.③ The relationship between confining pressure and shear stress is characterized by the central contour inclination in the nephogram of displacement field, so it can also be used as precursors of partial and global slip of the specimen.

It is of great significance to study the aerodynamic interference characteristics and the motion law of the airborne buoy during the launching process for the design of the safe launching scheme of the airborne buoy. Computational fluid dynamics (CFD) methods are used to simulate the release process of airborne buoy in reconnaissance and strike integrated unmanned aerial vehicle (R/S UAV). A dynamic chimera grid approach is used and coupled with 6-DOF movement equations to solve the unsteady N-S (Navier-Stokes) equations. The time-dependent interference between the stationary and moving boundaries is captured. All major parameters, such as displacement, angular orientations and force, and their change trends are obtained. The results show that free separation of buoy cover will have a significant impact on the safety of UAV during the release process of airborne buoy. Considering the state of the buoy cover attached to the buoy parachute, the closest range of buoy from the propeller is 0.151 m when the initial speed is 0 m/s, the safety margin is not enough; however, the closest range of buoy from the propeller is 0.671 m when the initial speed is 1.8 m/s, the safety margin is enough.

This paper mainly focuses on the classification of PPCPs in water bodies, their sources and their hazards, and focuses on the treatment technology of PPCPs in wastewater at home and abroad, comparing the advantages and disadvantages of each treatment technology and the current status of its application, with a view to discovering highly efficient measures for the treatment of PPCPs in wastewater, and providing reference for the development of wastewater treatment technology of PPCPs. [ABSTRACT FROM AUTHOR]

In view of the large number of joint power stations in the basin but the existence of disputes in the distribution of benefits, a more reasonable method of benefit distribution for cascade power stations is proposed. Based on Shapley value method and TOPSIS method, considering the contribution of power stations and the relative satisfaction of power stations with different objective allocation methods, this paper establishes a compensation benefit allocation model of cascade power stations based on TOPSIS-Shapley value method. At the same time, in order to solve the limitation of Shapley value method in solving the problem of joint scheduling gain allocation of multi-stakeholder cascade power stations, the paper introduces the idea of aggregation dimension reduction. The idea of the model is as follows : the increment of the cascade power generation benefits before and after the joint dispatching of the upstream power station is taken as the compensation benefit. Firstly, four different objective allocation methods are used to calculate the characteristic parameter indexes of the power station to form the basic decision matrix of TOPSIS. The TOPSIS principle is used to obtain the relative satisfaction of the power station to each allocation method. At the same time, the coalition game theory is used to calculate the power generation benefits of all possible coalition modes of the power station, and the compensation benefit allocation results based on Shapley value are obtained. Finally, the allocation coefficient obtained by TOPSIS principle is combined with the allocation coefficient obtained by Shapley value method to form a comprehensive allocation weight, which is applied to the compensation benefit allocation of eight-stage power station in the upper reaches of the Heihe River. The engineering application example shows that the method not only considers the marginal contribution of the union power station to the whole and the satisfaction degree of each power station, but also takes into account the difference of the characteristic index of the power station, and reasonably quantifies and distributes the power generation compensation benefit among the power stations. The allocation result is fair and reasonable and easy to be accepted by all parties, which can promote the power stations at all levels in the basin to participate in the joint dispatching so as to achieve the goal of maximizing the overall benefit. It has an important reference significance for the distribution of compensation benefits of a large number of cascade hydropower stations. [ABSTRACT FROM AUTHOR]

Understanding plant communities in desertification area is the scientific basis of evaluating the local eco-environmental quality and carrying out desertification control. According to longitude, we divided the desertification area in northwest Liaoning Province into three regions: the eastern region (122°50'37" -123°49'40" E), the middle region (121°16'41"-122°35'00" E), and the western region (119°20'03" -120°02'41" E), and investigated the plant communities in each region. The results showed that the proportion of forest and canopy density of tree layer increased from the west to the east. Ass. Pinus sylvestris var. moregolica and Ass. Populus sp. in the eastern, Ass. Pinus tabuliformis and Ass. Populus sp. in the middle, as well as Ass. P. tabuliformis and Ass. Prunus sibirica in the western were dominant communities, respectively. The proportion of brush community in the eastern, middle and western was 0, 22.2%, and 28.0%, respectively. Grasslands formed mainly by human disturbance in the eastern and middle regions. The total species numbers were 110 in the middle, 88 in the western and 75 in the eastern, respectively. Therophytes were dominant in the eastern and middle with proportions of 68.2% and 66.7%, respectively. Hemicryptophytes were the dominant type (36.3%) in the western region. The proportion of microphanerophyt, nanophanerophyte, chamaephyte, and geophyte increased from the eastern to the western. The species number, Shannon index, and Simpson diversity index of the middle were the highest among the three regions. Pielou evenness index increased gradually from the eastern to the western. Community similarity between the eastern and the western was the lowest, as shown by the β-biodiversity, and the similarity between the middle and the western was the highest. The community type, species number, characteristics of species composition and species biodiversity of the middle region had the characteristics of ecological transition zone. In general, vegetation status in the desertification area of northwest Liaoning Province was in good condition. There were still some problems including the monotonous vertical structure of forest and tree species as well as the serious human interference. [ABSTRACT FROM AUTHOR]

To determine the diversity of nitrogen-fixing and carbon-fixing microbial groups in aeolian sandy soil and the effects of sand-fixation plantation type on the structures of two microbial groups in the Horqin Sandy Land, we selected six representative sand-fixation vegetations with the same age, including Caragana microphylla, Artemisia halodendron, Salix gordejevii, Hedysarum fruticosum, Populus simonii, and Pinus sylvestris var. mongolica as well as their adjacent natural Ulmus pumila open forest as test objects to investigate the diversities and structures of nifH-and cbbL-carrying microbial communities in soil by high-throughput sequencing technique. The results showed that vegetation type significantly affected soil physical and chemical properties, microbiological activities, diversities and the main compositions of nitrogen-fixing and carbon-fixing microbial communities. The diversity of soil nitrogen-fixing microbial communities under S. gordejevii and P. simonii plantations and that of carbon-fixing microbial communities under P. sylvestris var. mongolica and P. simonii plantations were significantly higher than those of other plantations. Skermanella, Bradyrhizobium, Azospirillum, and Azohydromonas were dominant nitrogen-fixation genera, with the average relative abundance of 22.3%, 21.5%, 20.8%, and 17.8%, respectively. Soil carbon-fixation microbial communities were dominated by Pseudonocardia, Bradyrhizobium, Cupriavidus, and Mesorhizobium, with relative abundance of 22.4%, 18.5%, 10.5%, and 6.0%, respectively. Soil nitrogen-fixing microbial community under C. mirophylla plantation and carbon-fixing communities under S. gordejevii and P. simonii plantations were very close to those of natural U. pumila open forest. Soil organic matter, NH4+-N, and total phosphorus were the direct determining factors for nitrogen-fixing microbial community, while pH, soil moisture, and available phosphorus were main factors influencing carbon-fixing microbial community. These observations potentially provide the scientific foundations for evaluating the ecological benefits of revegetation practice in sandy lands. [ABSTRACT FROM AUTHOR]

[Objective] This study investigated the differences in fruit quality of Dawuxing loquat from different production regions to provide basis for high-quality production and cultivation of loquat. [Method] Dawuxing loquat from 7 production areas in China was collected, and appearance indicators including fruit weight, fruit shape index and chromatic aberration, main nutritional indicators including total sugar, titratable acid, vitamin C, total flavonoids and total phenols content, as well as soluble sugar components and organic acid components were measured and analyzed. The principal component analysis method was used to comprehensively evaluate fruit quality. [Result] There were significant differences in fruit characters and main components of Dawuxing loquat fruits from different producing areas (P<0.05). The fruit weight was 35.28-57.20 g with the highest in Ankang, Shaanxi, the edible rate was 78.03%-88.69% with the highest in Hechuan, Chongqing, and the fruit hardness was 3.23- 6.62 N with the highest in He-chuan, Chongqing. Chromatic aberration values L and b were the highest in Shaoguan, Guangdong, a was the highest in Mengzi, Yunnan, and the fruit was nearly round. The fruit water content was 85.46%-91.10% with the highest in Shaoguan, Guangdong, the total sugar content was 57.63 -126.27 mg/g with the highest in Mengzi, Yunnan, and the content of soluble solids was 8.79% -13.83% with the highest in Panzhihua, Sichuan. The titratable acid content was 0.20%-1.33% with the highest in Shaoguan, Guangdong, the solid acid ratio was 6.60-66.71 with the highest in Mengzi, Yunnan, and the content of vitamin C was 7.35-14.87 mg/hg with the highest in Mengzi, Yunnan. The carotenoid contents in Chengdu, Sichuan and Ankang, Shaanxi were significantly higher than those in other production areas (P< 0.05). The total flavone content was 26.37-92.43 mg/hg with the highest in Mengzi, Yunnan, and the total phenol content was 8.89-30.93 mg/hg with the highest in Hechuan, Chongqing. The soluble sugar components mainly included glucose, fructose and sucrose, and the main organic acid was malic acid. The comprehensive scores of loquat quality based on main nutritional components were in the decreasing order of Mengzi, Yunnan > Ankang, Shaanxi>Panzhihua, Sichuan> Chengdu, Sichuan> Hechuan, Chongqing>Xianning, Hubei> Shaoguan, Guangdong. [Conclusion] Climatic conditions such as latitude, altitude, light, temperature difference between day and night, rainfall and UV intensity were the key factors affecting loquat quality. [ABSTRACT FROM AUTHOR]

The state of health (SOH ) estimation of lithium batteries is low in accuracy while Gaussian process regression (GPR) is susceptible to local optimum and slow convergence speed. In this paper, the dragonfly algorithm (DA) is employed to optimize the hyperparameters of Gaussian process regression, and thus achieve accurate estimation of the nonlinear recession of lithium batteries. First, a number of features are selected from the charge/discharge cycle data of lithium batteries, including charging & discharging time and temperature change. Then, the correlation between these features and the SOH of lithium batteries is analyzed, and the features with higher correlation are selected as the health factors and taken as inputs to the model. The lithium battery degradation model is built by GPR and DA-GPR algorithms to predict the SOH of B0005, B0006 and B0007 on NASA battery datasets. The three sets of batteries are firstly charged in 1.5 A constant current mode (CC stage), and then changed to constant voltage mode when their voltage reaches the charging cut-off voltage of 4.2V (CV stage), and their charging is ended when the current of the batteries gradually decays to 20 mA. During the discharging process, the batteries are in 2A constant current mode until the battery B0005, B0006 and B0007 reaches the cut-off discharge voltage of 2.7 V, 2. 5 Vand 2. 2 V. Repeated charging and discharging will accelerate the aging process of lithium batteries. When the SOH of the test batteries is reduced to less than 70%, they reach their end of capacity and the experiment ends. The initial 75 cycles of B0005, B0006 and B0007 batteries are used as the training set and the remaining 90 cycles as the test set, in which the root mean square error (RMSE) for the Gaussian process regression (GPR) stands at 1.45, 0.285, and 2 768 4 respectively. In contrast, in the dragonfly algorithm-optimized Gaussian process regression (DA-GPR), the RMSE records at 0.119, 0.022 and 0.147, down by 91.79%, 92% and 94. 69% respectively. To verify the accuracy of DA-GPR prediction under limited number of samples, the first 10 cycles and the first 30 cycles of B0005 are selected as the training set, and the rest are used as the training set. Results show the RMSE of the first 10 cycles as the training set is 1.756 3, and that of the first 30 cycles as the training set is 0.150 71. To verify the generalizability of DA-GPR, B0006 and B0007 are chosen as training sets and B0005 as test set, whose RMSE reaches 0.74 4. In comparison with some other machine learning models, the RMSE of GPR reaches 1.545, of GA-BP (BP neural network optimized by genetic algorithm) 1 769 0, and of IGVO-SVR (support vector machine optimized by locust algorithm regression) 2.436. [ABSTRACT FROM AUTHOR]

ObjectiveTo investigate the expression profiles of sphingolipids in peripheral serum in patients with hepatitis B/C cirrhosis and those with non-viral hepatitis-related cirrhosis. MethodsA total of 104 patients with liver cirrhosis who were admitted to Difficult & Complicated Liver Diseases and Artificial Liver Center, Beijing YouAn Hospital, Capital Medical University, from July 2014 to May 2015 were enrolled as subjects, and finally 97 patients with liver cirrhosis were enrolled, among whom there were 66 patients (68.04%) with hepatitis B/C cirrhosis and 31 patients (31.96%) with non-viral hepatitis-related cirrhosis. High-performance liquid chromatography-mass spectrometry was used to measure the expression of 57 sphingolipids in peripheral serum. The t-test or the Mann-Whitney U test was used for comparison of continuous data between two groups, and the chi-square test was used for comparison of categorical data between two groups. The variables with statistical significance in the univariate analysis were included in the multivariate analysis. ResultsThere were no significant differences between the two groups in age, proportion of male patients, total bilirubin, direct bilirubin, and gamma-glutamyl transpeptidase (all P＞0.05). As for the 57 sphingolipids in peripheral serum, compared with the non-viral hepatitis-related cirrhosis group, the viral hepatitis-related cirrhosis group had significantly higher expression of Cer(d18∶1/12∶0) ［168.61 (16854-168.88) pmol/0.1 ml vs 168.53 (168.48-168.63) pmol/0.1 ml, Z=-2.54, P＜0.05］, HexCer (d18∶1/14∶1) ［213.93 (211.15-218.92) pmol/0.1 ml vs 212.26 (209.90-214.64) pmol/0.1 ml, Z=-2.03, P＜0.05］, and dhCer(d18∶0/24∶1)-1-P ［60.07 (59.40-61.23) pmol/0.1 ml vs 59.42 (59.28-59.87) pmol/0.1 ml, Z=-2.32, P＜0.05］. The logistic regression analysis revealed that high expression of dhCer(d18∶0/24∶1)-1-P was independently associated with hepatitis B/C cirrhosis (odds ratio=111, 95% confidence interval: 1.004-1.225, P=0.042). The subgroup analysis of the patients with viral hepatitis-associated cirrhosis showed that there were no significant differences between the patients with hepatitis B cirrhosis and those with hepatitis C cirrhosis in the expression of Cer(d18∶1/12∶0), HexCer (d18∶1/14∶1), and dhCer(d18∶0/24∶1)-1-P (Z=-0.563, -0.610, and -0.579, all P＞0.05). ConclusionThe sphingolipid dhCer (d18∶0/24∶1)-1-P in peripheral serum is closely associated with hepatitis B/C cirrhosis and may help to understand the features of viral hepatitis-related cirrhosis from the perspective of sphingolipids.

In order to make the research of digital steganography model develop synchronously with steganography research, three digital steganography models from general to specific are proposed, and each model was formalized. Through study on digital model, the essential principles of steganography algorithm were summarized to guide the further development of steganography. Firstly, aiming at the problem that the existing model cannot describe the emerging steganography algorithms, a general digital steganography model was proposed to describe nearly all steganography algorithms. Secondly, in view of the important position of the cover modification steganography algorithm in the research of steganography, a cover-modification digital steganography model was proposed. Then, for the current mainstream image adaptive steganography algorithm, a digital image adaptive steganography model with minimal distortion was proposed. Four typical steganography algorithm were selected as examples which were described by the proposed steganography model to validate the effectiveness of the proposed model.