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Background Carotid atherosclerosis (CAS) is often considered an early warning signal for cardiovascular diseases (CVD). The diagnostic technique of carotid artery Doppler ultrasonography has not been included in public health service programs, and the Framingham Risk Score (FRS) lacks accuracy in assessing CAS risk, hindering the identification of CAS by primary healthcare personnel. Currently, there is a lack of research on machine learning methods to identify CAS in the medium-high risk population assessed by FRS. Objective To construct a CAS risk prediction model for the medium-high risk population assessed by FRS using machine learning methods, compare its discriminative efficacy, select the optimal model, and assist primary healthcare personnel in identifying CAS more conveniently and accurately. Methods Using convenience sampling method, a total of 674 local residents from two townships in Liuzhou City, Guangxi Zhuang Autonomous Region, who met the inclusion criteria from 2019 to 2021 and 2023, were selected as the study subjects. Relevant information was collected, and biochemical indicators were measured in fasting blood and urine samples. FRS was used to assess the risk of CVD occurrence, and carotid ultrasound was used to diagnose CAS. Among the 517 subjects from 2019 to 2021, a random 8∶2 split was used to create a training set and a validation set. The training set was used to build Logistic regression, Random Forest (RF), Support Vector Machine (SVM), Extreme Gradient Boosting (XGBoost), and Gradient Boosting Decision Tree (GBDT) models, while the validation set was used for internal validation. The 157 subjects from 2023 served as the test set for external validation. Feature variables were selected using Lasso regression analysis, and discriminative efficacy was evaluated using sensitivity, specificity, accuracy, F1 score, and area under curve (AUC) value. External validation assessed the generalization ability of the optimal model using AUC value, and the Shapley Additive exPlanation (SHAP) method explored the important variables influencing the optimal model's identification of CAS. Results Lasso regression analysis identified 15 feature variables: age, BMI, systolic blood pressure (SBP), smoking, drinking, hypertension, total cholesterol, high density lipoprotein cholesterol, C-reactive protein (CRP), fasting plasma glucose, apolipoprotein B (ApoB), lipoprotein a (LPA), aspartate aminotransferase (AST), AST/ alanine aminotransferase, urinary microalbumin creatinine ratio. The constructed Logistic regression, RF, SVM, XGBoost, and GBDT models exhibited high AUC values, with the GBDT model showing the best discriminative performance. Its sensitivity, specificity, accuracy, F1 score, and AUC value were 0.755 1, 0.836 4, 0.798 1, 0.778 9, and 0.834 9, respectively, and the external validation AUC value was 0.794 0. The SHAP method revealed that age, SBP, CRP, LPA, and ApoB were the top five factors influencing the GBDT model's identification of CAS. Conclusion Logistic regression, RF, SVM, XGBoost, and GBDT models for identifying CAS based on machine learning all demonstrated high discriminative performance, with the GBDT model exhibiting the best comprehensive discriminative efficacy and strong generalization ability.

This study was performed in order to investigate the impact of steaming and boiling on the color, free and ester-type astaxanthin contents and in vitro antioxidant activity of different parts of crayfish. The results demonstrated that both cooking treatments had significant effects on the astaxanthin contents, color, and antioxidant activity of the different parts of crayfish. The astaxanthin contents of all crayfish parts increased initially and then declined with cooking time. Fresh crayfish tail shells were found to contain free astaxanthin and five astaxanthin monoesters. Free astaxanthin and one astaxanthin monoester were found in boiled crayfish tail shells, suggesting that boiling could promote the hydrolysis of esterified astaxanthin and the consequent generation of 98% free astaxanthin. With cooking time increasing, the L* value of crayfish increased slowly, and the a* value initially increased and later decreased, while the W value showed no significant change. Moreover, the a* value was strongly correlated with the astaxanthin content (r > 0.4). Both hydroxyl and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity increased first and subsequently declined. All parts of crayfish maintained high scavenging capacity against 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radicals. For all parts of steamed crayfish, astaxanthin contents showed a strong correlation with DPPH radical scavenging capacity (r > 0.9), but had a significant positive correlation with hydroxyl radical scavenging capacity for both claws and meat (P 0.9, P < 0.05).

The structural heterogeneity and complexity of plant cell wall polysaccharides limit the release of phytonutrients in food processing, ultimately affecting the sensory quality, nutritional value, and shelf stability of products. Efficient enzymatic hydrolysis using plant cell wall polysaccharide-degrading enzymes (PCWPE) is a key step in overcoming the plant cell wall, a chemically complex structure composed mostly of polysaccharides, in food processing. PCWPE include cellulase, hemi-cellulase and pectinase, which specifically and efficiently hydrolyze glycosidic bonds in plant cell wall polysaccharides, significantly improving the sensory flavor and nutritional value of products, enhancing the stability of multiphase systems, and increasing the product yield. In recent years, PCWPE have been widely used in beverage processing, phytonutrient extraction, functional sugar preparation, and the processing of emerging sustainable plant-based food and thereby have become a research hotspot in the field of green food processing. This article summarizes the latest research on the mechanism of action of PCWPE, efficient enzymatic hydrolysis techniques and their application in the food industry, with a view to providing a reference for technological innovation in the field of high-quality plant-based food processing.

A flexible wipe paper for rapid nondestructive detection of ferbam residues on the surface of fruits and vegetables by surface-enhanced Raman scattering (SERS) was prepared using filter paper as the substate by a simple soaking method. The synthesis and storage conditions were optimized to ensure that the SERS method has excellent performance. The results showed that concentration factor of silver nanoparticles (AgNPs), soaking time in AgNP solution and drying method greatly affected the performance of the SERS wipe paper. The performance under the condition of soaking for 8 h in a 5-fold concentrate of AgNP solution was significantly better than that under other conditions. The SERS wipe paper prepared by vacuum drying had better performance that those prepared by other drying methods. After 9 days of storage at −20 ℃, the optimized substrate retained approximately 50% of the original peak value. Besides, it exhibited good sensitivity, uniformity, and repeatability. The limit of detection (LOD) for ferbam on a glass plate was 4.07 × 10-6 mg/mL, and the LOD for ferbam on the surface of spinach and nectarine were 0.043 and 0.062 mg/kg, respectively. This study provides an excellent basis for the development and utilization of SERS wipe paper.

Objective To establish and forensically verify a 42 microhaplotypes （mircohaps, MHs） multiplex assay system based on next-generation sequencing （NGS）, and to explore the application value of this system in the practice of forensic genetics. Methods A total of 42 highly polymorphic MHs were selected from previous studies, and sequenced by the MiSeq FGxTM platform to verify the repeata-bility, sensitivity, specificity, stability, and mixture analysis ability of the detection system. Through population genetic investigation of 102 unrelated Chinese Han individuals in Liyang City, Jiangsu Province, China, the application value of this system in forensic genetics was evaluated. Results The sequencing repeatability of the 42-plex MHs assay was 100% and the sensitivity was as low as 0.062 5 ng. The system had the ability to withstand the interference of indigo （≤2 500 ng/μL）, humic acid （≤9 ng/μL）, hemoglobin（≤20 μmol）, and urea （≤200 ng/μL） and to detect mixtures of 2 people （1∶19）， 3 people （1∶1∶9） and 4 people （1∶1∶1∶9）. Based on 102 individual data, the combined power of discrimination and the combined power of exclusion were 1-3.45×10-30 and 1-3.77×10-11, respectively, and the average effect value of alleles was 2.899. Conclusion The 42-plex MHs assay was successfully established in this study and this system has high repeatability and sensitivity, good anti-jamming ability and mixture analysis ability. The 42 MHs are highly polymorphism and have good application value in individual identification and paternity testing.

The nuclear criticality safety issue in spent fuel reprocessing facilities is closely related to the main process and is almost equally important. It is closely related to the design and operation of reprocessing facilities. The requirement of nuclear criticality safety greatly restricts the operational capacity of the spent fuel reprocessing process, thereby affecting the economic efficiency of reprocessing. In the post-processing process, both multiphase uranium-plutonium mixed systems and multi body interaction systems are involved. The system characteristics are complex, and experimental simulation is difficult, which greatly restricts the further improvement of the production and operation capabilities of the pilot plant. However, due to the criticality safety challenges caused by reactivity changes such as the non-uniformity, dynamic complexity, and instability of the solution in the reactor under boiling nitric acid during the dissolution process, it has become a key research topic in various countries. According to the criticality safety problem of nuclear fuel dissolution process, the criticality effect of nitric acid concentration was studied. The criticality experiment data of nuclear fuel dissolution process were obtained by keeping the concentration of nitric acid in the same fuel concentration. Four experiments were conducted with different concentrations of nitric acid. During the experiment, the subcritical extrapolation method, reactivity interpolation method, and stable power method were used to complete the criticality experiment. The experimental results show that with the increase of nitric acid concentration, the relative deviation of the criticality experiment data is 0.068%, and the relative deviation between the criticality experiment results and the theoretical calculated values is 0.39%. The research results show that the reactivity of the system gradually increases as the concentration of nitric acid decreases. Therefore, it is necessary to consider the reactivity changes caused by changes in the criticality safety of the spent fuel dissolution process, and high attention is needed. According to the agreement between the experiment and the theoretical calculation, it is appropriate to use the Monte Carlo code MONK to calculate and analyze the acidity effect of the solid-liquid two-phase solution system, which can be used as a nuclear criticality safety control engineering design process for the solid-liquid two-phase nuclear fuel dissolution system. This series of experiment data can be used for calculation, verification, and safety evaluation of critical analysis under solid-liquid coexistence conditions of nuclear fuel. This paper results provide data support for improving the criticality safety control level of critical post-processing equipment.

O—butyl—N—isobutyl thionocarbamate (NBIB) is a novel collector for copper sulfur flotation separation. The adsorption capacity of NBIB was measured using a UV–vis spectrophotometer. The effects of the adsorption temperature, pH value, stirring time, and collector concentration on the adsorption capacity of NBIB on chalcopyrite surfaces, as well as its adsorption thermodynamics and kinetics, were investigated. Results of a pure mineral flotation experiment indicate that NBIB has a high recovery rate for chalcopyrite, strong collection capacity, and little influence by pH. The adsorption capacity of NBIB on a chalcopyrite surface increases with an increase in the collector concentration at 288, 298, and 308 K and pH 6, 9, and 12, respectively. When the equilibrium concentration reaches 0.5×10−4 mol·L−1, the adsorption capacity has a small increase range. At the same pH value, the adsorption capacity increases with an increase in the adsorption temperature. It is speculated that NBIB adsorption on a chalcopyrite surface is an endothermic process. At pH 6 and 9, little difference exists in adsorption capacity, which slightly decreases when pH increases to 12. Meanwhile, the pulp pH value has little effect on the adsorption capacity, which is consistent with the flotation test results. The adsorption capacity data were linearly fitted by Langmuir and Freundlich isotherms, and the Langmuir equation has a better correlation coefficient of the fitting curve. The adsorption process of NBIB on the chalcopyrite surface is more consistent with the Langmuir adsorption model, and it is speculated that the adsorption process may be monolayer adsorption. The parameters of the Langmuir equation are considered based on a thermodynamic formula. The results indicate that the linear fitting results are good, ∆G is negative, and ∆H and ∆S are positive. Therefore, the process of chalcopyrite adsorbing NBIB may be spontaneous, entropy-driven, and endothermic chemical adsorption. Meanwhile, the adsorption capacity of NBIB on the chalcopyrite surface increases with an increase in the adsorption time at temperatures from 288 K to 308 K. The increasing trend of adsorption capacity slows down after the adsorption time reaches 20 min. Moreover, the adsorption capacity increases with increasing temperature. Evidently, the adsorption is an endothermic process, which is consistent with the results of the thermodynamic analysis. The kinetic calculation shows that the correlation coefficients of the second-order reaction fitting curve are greater than those of first-order reaction, indicating that the second-order reaction rate equation has a better linear fitting result. The equilibrium adsorption capacity calculated by the second-order reaction rate equation is closer to the experimental equilibrium adsorption capacity. Therefore, it is speculated that the NBIB adsorption on the chalcopyrite surface conforms to the second-order adsorption kinetic model.

The integration mechanism of medical treatment and prevention based on family doctor teams is a key way to break down the barrier between "medical" and "prevention". In this paper, we explain the definition and connotation of treatment-prevention integration, review the development history of family doctor teams, systematically review the typical practice strategies and the shortcomings of treatment-prevention integrationon family doctor teams in China. Measures should be taken to promote the treatment-prevention integration, including improve the talent training system, change views of "attaching importance to treatment and neglecting prevention", strengthen the organization and management, innovate the assessment and incentive mechanism, reform the medical insurance payment method, encourage diversified forms of services, etc. The study aims to provide reference for improving the quality of services and developing treatment-prevention integration in the future.

Background During the containment of COVID-19, the traditional face-to-face interventions conducted at the rehabilitation center were plagued by many limitations, while internet-based interventions can overcome the limitations of geographic location, working hours and transportation, with less medical costs. Objective To examine the effects of internet-based interventions on knowledge, attitude/belief and practice (KAP) toward rehabilitation exercises, physical activity (PA) level, and exercise compliance inpatients after PCI. Methods The subjects were 76 patients who received their first PCI in Department of Cardiology, Tangshan Gongren Hospital from November 2021 to June 2022. They were randomly and equally divided into two groups to receive either internet-based intervention with routine nursing (experimental group) or routine nursing (control group) . Before and three months after the intervention, the Rehabilitation Exercise Knowledge-Belief-Practice Scale for Patients with Coronary Heart Disease (REKBPCHD) , the International Physical Activity Questionnaire-Short Form (IPAQ-SF) , and Patients' Exercise Log were used to assess the KAP level, PA level, and exercise adherence, respectively. The impact of network intervention on exercise adherence in patients after PCI by univariate Logistic regression analysis. Results After 3 months of intervention, a significant increase was found in the average total score of REKBPCHD, and the average scores of the knowledge dimension, attitude dimension and practice dimension of the scale in the experimental group (P

Objective To explore the effect of copy number variation on the occurrence and development of hepatocellular carcinoma by using copy number variation and transcriptome experiment of hepatocellular carcinoma combined with public clinical data. Methods The copy number variation found in hepatoma cell lines HepG2 and Huh7 was identified by optical genome mapping. The function of the copy number variant genes in the two cell lines was analyzed, and the protein interaction network was mapped according to the enrichment pathway. Key genes in the core network of two cell lines were selected to analyze the relationship between copy number variation and gene expression in hepatocellular carcinoma. The relationship between gene expression and clinical survival was analyzed by GEPIA database. RNA-seq assay and public data were used to verify gene expression levels. Results HepG2 cells mainly showed increased copy number, and related genes were enriched in estrogen signaling pathway and Staphylococcus aureus infection pathway. Huh7 cells showed both increased and decreased copy number, and related genes mainly concentrated in olfactory conduction and cytokine-cytokine receptor interaction pathways. The copy number of key genes SRC, MAPK3 and MAP3K7 was proportional to gene expression, and survival was significantly reduced in patients with high expression of these genes (P＜0.05). Compared with HEK293T cell line, the expression of SRC and MAP3K7 genes in the two hepatocellular carcinoma lines was significantly increased(P＜0.001), suggesting the specific variation of hepatocellular carcinoma. MAPK3 had no difference. Conclusions The expression of copy number variant genes SRC and MAP3K7 in hepatocellular carcinoma is significantly correlated with the prognosis of patients, and may significantly affect the development and heterogeneity of hepatocellular carcinoma.

On July 23, 2022, the World Health Organization (WHO) declared the mpox epidemic as a Public Health Emergency of International Concern (PHEIC), indicating the seriousness of the mpox epidemic. Mpox is a rare zoonotic infectious disease caused by mpox virus infection, mostly occurred among the men who have sex with men (MSM), but general populations are susceptible to the infection and the risk of imported infection is high. In this paper, we discussed the strategy for prevention and control of mpox epidemic in China using strengths, weaknesses, opportunities and threats (SWOT) analysis based on the experience in the containment of severe acute respiratory syndromes (SARS) in 2003 and coronavirus disease 2019 (COVID-19) in recent three years, for providing a reference to relevant decision-making.

[Objective] The ecological and environmental effects of land use transition and their development trends were analyzed in order to provide a basis for promoting land use transition, low-carbon cycle development, and realizing the goal of "double carbon" . [Methods] We used land use data for Zunyi City of Guizhou Province in 2005, 2010, 2015, and 2020 and spatial analysis technology for this study. [Results] ① Land transformation from 2005 to 2020 was mainly manifested by the interconversion between carbon sink sites and the transformation of carbon sink sites to carbon source sites. ② Net carbon emission increased from 5.99×105 tons in 2005 to 9.87×106 tons in 2020, an increase of 9.27×106 tons (1 548.15%). However, the incremental amount gradually decreased, and the rate of increase gradually decreased. ③ The value of ecosystem services in Zunyi City increased from 7.64×1010 yuan in 2005 to 7.73×1010 yuan in 2020, showing a fluctuating upward trend, with a total increase of 9.14×108 yuan and a growth rate of 1.2%. ④ The gray prediction model showed that the net carbon emissions and ecosystem service value for Zunyi City will continue to increase in the future, with both showing a consistent upward trend. [Conclusion] Zunyi City continues to facing considerable pressure in terms of the ecological environment, and needs to increase efforts to enhance the value of ecosystem services while striving to achieve the goal of carbon peaking.

With the increasing inequality of network attack and defense in the Internet era, threat intelligence has become one of the important tools to narrow this gap.Based on the analysis of the research status of threat intelligence at home and abroad, a set of construction methods of threat intelligence systems suitable for telecom operators were proposed, including six steps: intelligence planning, intelligence production, intelligence analysis, intelligence management, intelligence sharing and intelligence application.Meanwhile a set of multi-source intelligence fusion assessment mechanisms was presented, and the technologies and methods were systematically expounded involved in the four stages of intelligence aggregation analysis, intelligence reputation analysis, intelligence correlation analysis and intelligence aging analysis, so as to help the telecom operators build the ability of intelligence fusion analysis.At the same time, the principles of intelligence production and synchronous application were given for intrusion and loss intelligence, which provided a useful reference for telecom operators to apply threat intelligence technology to build a security protection system.

There are obvious differences in spatial and temporal distribution characteristics of atmospheric water vapor and its relationship with precipitation under different topography and climate background conditions.Hexi Corridor located in inland arid region of Northwest China， so it is necessary to understand deeply and meticulously the changes of atmospheric precipitable water vapor.In this paper， based on precipitable water vapor data derived from ground-based GPS measurements （hereinafter referred to as GPS/PWV）， radiosonde data and ground conventional observation data at Zhangye National Climate Observatory from October 2016 to May 2019， the usability of GPS/PWV data was discussed firstly， then the temporal variation characteristics of PWV and its relationship with precipitation and surface water vapor pressure in arid area of the Hexi Corridor were analyzed.The results are as follows： （1） The GPS/PWV were higher consistent with calculated PWV by using radiosonde data.The root mean square error and average deviation were 2.01 mm and 1.16 mm respectively， and their correlation coefficient reached 0.97 and above.Therefore， GPS/PWV data had higher accuracy and availability.（2） The monthly distribution of atmospheric PWV appeared unimodal pattern， which was in good agreement with monthly precipitation.PWV was the maximum in August （23.24 mm） and the minimum in February （2.55 mm）.Precipitation was not only affected by PWV， but also related to precipitation conversion rate.The monthly precipitation peak behind the PWV peak because the precipitation conversion rate in July was higher than that in August.The diurnal variation of PWV was opposite to temperature， they had significantly negative correlation.The peak value of PWV appeared at 01:00 UTC， while the valley value appeared at 08:00 UTC.（3） The base value of PWV was 8.4 mm in arid area of the Hexi Corridor.When the rainfall occurs， PWV was mostly higher than the base value， and PWV increased sharply 7~11 hours before the precipitation， the increment generally exceeds 3.0 mm.The most rainfall started around the maximum PWV and ended the rapidly decreasing stage of PWV， and the maximum precipitation intensity and PWV appeared concurrently， or the maximum precipitation intensity was typically 1 hour behind the maximum PWV， which could be used as a reference index for precipitation forecast.（4） PWV on rainy days was significantly higher than that on non-rainy days.The analysis also showed that PWV had no obvious significance for the indication of snowy weather in arid areas.（5） There was a quadratic polynomial relationship between PWV and surface water vapor pressure in arid area of the Hexi Corridor.

Due to the detection sensitivity provided by the high nuclear spin polarization, hyperpolarized 129Xe has been employed in animal and human magnetic resonance imaging (MRI). However, during the accumulation-thawing process of hyperpolarized 129Xe, multiple factors lead to the relaxation of spin polarization and would hinder the wider application of 129Xe. In this research, the spin relaxation mechanism of hyperpolarized 129Xe during the accumulation-thawing process is investigated by both theoretical model analysis and experimental measurements. Meanwhile, the stability of the homebuilt device for the accumulation-thawing is measured. Our results demonstrate that the thawing mode and the cold trap material significantly affect the polarization loss; the automatic device is very stable during long-term operation and shows a high degree of automation, resulting in a polarization recovery ratio of 85.6% ± 4.7%. This research greatly helps to improve the efficiency of hyperpolarized 129Xe in animal and human MRI.

To solve the problem that existing contrastive prediction based self-supervised speech representation learning methods need to construct a large number of negative samples, and their performance depends on large training batches, requiring a lot of computing resources, a new speech representation learning method based on contrastive learning using only positive samples was proposed.Combined with reconstruction loss, the proposed method could obtain better representation with lower training cost.The proposed method was inspired by the idea of the SimSiam method in image self-supervised representation learning.Using the siamese network architecture, two random augmentations of the input speech signals were processed by the same encoder network, then a feed-forward network was applied on one side, and a stop-gradient operation was applied on the other side.The model was trained to maximize the similarity between two sides.During training processing, negative samples were not required, so small batch size could be used and training efficiency was improved.Experimental results show that the representation model obtained by the new method achieves or exceeds the performance of existing mainstream speech representation learning models in multiple downstream tasks.

Submarine pipelines are important means for offshore oil & gas transportation, and thus facilitating the development of submarine pipeline engineering technologies is of great significance to promote the development and construction of offshore oil and gas fields in China. Herein, the development status of submarine pipeline engineering technologies in China was expounded from the perspectives of the technical challenges faced by the submarine pipeline engineering, the development history and the progress of localization. In terms of technical challenges, the differences of the complex medium transported by submarine pipelines and the harsh marine, geological and geomorphic environments in China from those of international offshore oil and gas development were highlighted. In terms of development history, the development process of submarine pipeline industry in China was summarized and divided into five stages, i.e., the forming stage, the growth stage, the development stage, the expanding stage and the leap stage. Besides, the localization progress of submarine pipelines was traced back. In terms of engineering technology system, the development status of technologies was reviewed from the four points of gathering process, structure design, installation, and maintenance and emergency repair of China's submarine pipelines. Finally, the future development trend of submarine pipeline engineering technology and equipment in China was prospected.

In order to reveal the water consumption characteristics of typical alpine meadow and alpine swamp wetland on the Qinghai-Xizang Plateau， taking alpine meadow in Maqin area and alpine swamp wetland in Yushu Longbao area of Qinghai-Xizang Plateau as observation stations， the actual evapotranspiration was taken as the research object.The eddy correlation system was used to preprocess the original observation data by eddy correlation theory.The changes of actual evapotranspiration in different time scales and different underlying surfaces were analyzed， and the influence of typical environmental factors on actual evapotranspiration was explored.In the process of flux observation， the observation data will be abnormal and missing due to instrument failure， weather conditions， atmospheric stability， and power supply system failure.Therefore， data elimination and interpolation are needed to obtain a complete flux time series.In this study， combined with meteorological and hydrological factors （ net radiation， temperature， relative humidity， soil heat flux， wind speed， soil moisture content ）， Random Forest （ RF ） method was used to interpolate monthly evapotranspiration， and the interpolation accuracy was higher ［R2=0.80~0.91， RMSE=0.05~0.08 mm·（30min）-1， MAE=0.03~0.04 mm·（30min）-1］.The results showed that： （1） Evapotranspiration of alpine meadow and alpine swamp wetland mainly concentrated in May to September.The monthly average evapotranspiration of alpine meadow was 123.46 mm， and the highest evapotranspiration was 160.88 mm in July.The average monthly evapotranspiration of alpine swamp wetland was146.76 mm.Evapotranspiration peaked in August at 168.41 mm.Evapotranspiration peaked at 14-15 hours a day.The trend of daily evapotranspiration and monthly evapotranspiration was similar， and evapotranspiration was mainly concentrated in the growing season.（2） For different underlying surfaces， the correlation between evapotranspiration and meteorological factors is different.Among them， the correlation between evapotranspiration and meteorological factors in alpine meadow ranked the first three as net radiation， temperature， and relative humidity， indicating that radiation energy budget is the most critical factor affecting evapotranspiration in Maqin area.Soil heat flux， net radiation and relative humidity are the main factors of alpine swamp wetness.According to the importance estimation method in random forest model， the contribution of net radiation to evapotranspiration in alpine meadow is the most prominent， and the soil heat flux is low， while the contribution of soil heat flux to evapotranspiration in alpine swamp wetland is the largest， followed by net radiation， indicating that soil heat flux is the key factor affecting the evapotranspiration process when the underlying surface is alpine swamp wetland.（3） Analysis of variation characteristics of water consumption （IETP） of different underlying surfaces shows that the underlying surfaces of Maqin alpine meadow and Longbao alpine swamp wetland are dominated by water consumption， accounting for 69% and 80% respectively.Through understanding the actual evapotranspiration characteristics of alpine meadow and alpine wetland ecosystems， it provides reference and data support for the study of water cycle of alpine meadow and alpine wetland in Qinghai-Xizang Plateau.

To respond to the demand of achieving carbon peaking and carbon neutrality goals, and to construct a complete “source-grid-load-storage” new energy power system, a distributed photovoltaic net load forecasting model based on Hamiltonian Monte Carlo inference for deep Gaussian processes (HMCDGP) is proposed. First, direct and indirect forecasting methods are used to examine the accuracy of the proposed model and to obtain spot forecasting results. Then, the proposed model is used to perform probability forecasting experiments and produce interval prediction results. Finally, the superiority of the proposed model is verified through the comparative experiments based on the net load data of 300 households recorded by Australia Grid. After obtaining the exact net load probabilistic forecasting results, the photovoltaic production can be fully utilized via power dispatch, which can reduce the use of fossil energy and further reduce the carbon emission.

To solve the abuse of the Android application permission mechanism, a method of Android application access control based on virtual machine bytecode injection technology was proposed.The security policy in the form of virtual machine bytecode was generated according to the user’s security requirement and usage scenario, and injected into the coding unit of Android application that involves dangerous permission request and sensitive data access, to realize dynamic application behavior control.Tests on applications crawled from four mainstream domestic App stores show that the method can effectively intercept sensitive API calls and dangerous permission requests of legitimate App programs and implement control according to pre-specified security policies.Also, after injecting virtual machine bytecode, most of the App program operation is not affected by the injected code, and the robustness is guaranteed.The proposed method has a good universality.

The research focused on detecting solvent residues in two typical composite film bags made of biaxially oriented polypropylene/low-density polyethylene (BOPP/LDPE) and nylon/cast polypropylene (PA/CPP), and investigated their migration patterns. The non-compliance rate of solvent residue in the selected two typical material samples is 90%. After 18 months of storage at room temperature, the total solvent residue in BOPP/LDPE samples decreased by 95%, and the total solvent residue in PA/CPP samples decreased by more than 88.2%. Four different temperatures were tested, and after 1 hour at 80 °C, the residual solvents in the BOPP/LDPE samples evaporated completely; the total amount of solvent residue in PA/CPP samples decreased by more than 95.8%. Both an increase in experimental temperature and an extension of time will cause a decreasing trend in the total solvent residue and benzene residue in the composite film bag. The material, test temperature, and test time of plastic composite film bags for food have important effects on the migration pattern of solvent residues in two typical material samples. It is suggest revising the corresponding testing method standards, actively promoting the evaluation of green packaging for products, and better ensuring the quality of plastic composite film bags for food. [ABSTRACT FROM AUTHOR]

The controller placement is an important problem in software defined networks. Existing researches pay more attention to deploying controller planning for node failures and ignore the fact that the link failure can also effect the network drastically. To solve the problem, a mathematical model for the controller placement that plans ahead for the link failures to avoid a drastic increase failure recovery cost was proposed. To solve the model, an algorithm based on simulated annealing was designed. The simulation results show that the proposed model and algorithm can improve the robustness of the network. The maximum failure recovery cost is significantly reduced when a link falls in failures.

Different from the public chain, the consortium blockchain Hyperledger Fabric integrates the additional member management service(MSP) mechanism to provide channel-based data isolation protection. However, the data isolation protection mechanism still synchronizes the plaintext data within a channel, so there is a risk of data leakage. Besides, the channel-based data access control mechanism does not apply to some fine-grained privacy protection scenarios. To solve the problems of data privacy and security involved in the consortium chain Hyperledger mentioned above, a blockchain data access control scheme based on the CP-ABE algorithm was proposed. Based on the original existing Fabric-CA module in the Hyperledger, our scheme can realize the secure distribution of user attribute keys in the CP-ABE scheme while implementing the fine-grained security access control of blockchain data at the user level. The security analysis shows that the scheme achieves the security goals of ABE user attribute private key security distribution and data privacy protection. The performance analysis also shows that the proposed scheme has good usability.

本研究旨在瞭解我國初任教師在工作困擾、教學效能與專業表現的狀況，並分析在不同教學階段及任教區域的初任教師之差異。本研究使用教育部「師資培育長期追蹤資料庫整合型調查計畫」之「104 學年度初任教師調查」，該資料庫對我國 104 學年度初任教師進行普查， 回收樣本共 3,271 筆，其中有效樣本為 1,621 筆。本研究根據研究結果進行分析與討論，獲致以下結論：一、初任教師在教學上所面對的挑戰，以學生程度差異大及如何促進學生學習為主；二、不同教育階段與任教區域的初任教師在工作困擾、教學效能與專業表現上存在差異；三、初任教師的工作困擾與教學效能可以預測其專業表現。 This study explored the current job-related problems faced by beginning teachers, their teaching effectiveness, and professional performance in Taiwan. Additionally, it analyzes the difference between teachers at different teaching stages and in different teaching areas. This study used the Ministry of Education’s database of 104 school year beginning teacher survey. The sample population included 1,621 Taiwanese beginning teachers. The major results present the following: First, the main challenges faced by beginning teachers in teaching are the differentiation of student levels and how to facilitate student learning. Second, beginning teachers in different education stages and teaching areas show significant differences in terms of job problems, teaching effectiveness, and professional performance. Third, the job problems and teaching effectiveness of beginning teachers can predict their professional performance.

Objective To establish a linear relationship between age and the development process of the mandibular second, third molars in a northern Chinese population and test its accuracy in inferring whether the subject is over 18 years old. Methods The orthopantograms （OPGs） of 960 northern Chinese people aged between 10.00 to 25.99 years were selected. The gender, birth date, and date of the orthopantograms of each sample were recorded. The development stages of left mandibular second and third molars were divided with Demirjian method. The experimental group （760 individuals） constructed a Logistic regression equation to infer whether the subject is over 18 years old. The validation group （200 individuals） tested the accuracy of the equation. Results When only using third molar, the formula obtained for inferring whether the subject’s age is over 18 years is： logit P1=-18.276+0.494 x1+2.953 x3. When combining the second and the third molars, the formula is： logit P2=-21.045+3.177 x1+0.619 x2+2.088 x3. （x1 stands for gender, male is marked as 1 and female is marked as 2; x2 and x3 stand for the development stage of second molar and third molar, respectively）. The accuracy rates of this equation in estimating whether ages of subjects from the validation group were over 18 years old for males and females were 88.0%-92.0% and 85.0%-88.0%, respectively. Conclusion The age estimation formulas based on the development of mandibular second and third molars have important value in judging whether the individual is over 18 years old. Meanwhile, the accuracy of age estimation can be improved by combining the development of second and third molars together.

For the limitations of existing IPTV system in personal service,interactive service,the existing and developing dynamic media packaging technologies were studied.In order to make dynamic media packaging technologies easy to apply in the IPTV system,a method that adding the label information to the source for MPEG-2 standard encoding was proposed,and TS package technology was used to transmit,and finally decoding was achieved by the decoder.This technology had been used in realizing the system of nine screens hottest business system and had achieved practical application.

Objective To investigate the application of skull digital radiography (DR) during the follow-up after endovascular treatment of intracranial aneurysms. Methods Forty-three patients with intracranial aneurysms underwent endovascular coil embolization or stent angioplasty assisted by coil embolization. Three months later, they underwent skull DR and digital subtraction angiography (DSA) to observe the location and morphology of coils and whether there was recurrence of aneurysms. Results Among 43 patients, there were 14 cases of anterior communicating artery aneurysms, 17 cases of posterior communicating artery aneurysms, 5 cases of middle cerebral artery aneurysms, 5 cases of basilar artery aneurysms and 2 cases of posterior inferior cerebellar artery aneurysms. The coincidence of skull DR and DSA in detecting the form of coils was about 97.67% (42/43). DSA found 2 cases had recurrence, while skull DR found only one case with recurrence. There was no statistical difference between the two methods (χ2 = 0.345, P = 0.955). Conclusions Skull digital radiography is a safe and effective method with high accuracy in the follow-up examination after endovascular treatment of aneurysms. DOI: 10.3969/j.issn.1672-6731.2015.02.010

Objective To investigate the application of skull digital radiography (DR) during the follow - up after endovascular treatment of intracranial aneurysms. Methods Forty - three patients with intracranial aneurysms underwent endovascular coil embolization or stent angioplasty assisted by coil embolization. Three months later, they underwent skull DR and digital subtraction angiography (DSA) to observe the location and morphology of coils and whether there was recurrence of aneurysms. Results Among 43 patients, there were 14 cases of anterior communicating artery aneurysms, 17 cases of posterior communicating artery aneurysms, 5 cases of middle cerebral artery aneurysms, 5 cases of basilar artery aneurysms and 2 cases of posterior inferior cerebellar artery aneurysms. The coincidence of skull DR and DSA in detecting the form of coils was about 97.67% (42/43). DSA found 2 cases had recurrence, while skull DR found only one case with recurrence. There was no statistical difference between the two methods (χ² = 0.345, P = 0.955). Conclusions Skull digital radiography is a safe and effective method with high accuracy in the follow-up examination after endovascular treatment of aneurysms. [ABSTRACT FROM AUTHOR]

Regarding to the stability limitation of the traditional linear control,an improved nonlinear control strategy derived on Lyapunov direct method was proposed for the single phase Buck inverter. On the basis of the quasi steady state average model of the proposed system,a quadratic energy-like Lyapunov function was presented and as well as its control law,which a stable convergence of the proposed system. The duty cycle of the control equation was carried out by using integral reset circuit. Implementation of the proposed controller is simple. Moreover,the stability of the proposed system was verified in theory and system performace analysis was shown,including the model comparison results between the proposed system and the traditional PID control one. Finally,the experimental circuit was conducted. The proposed experiment results show the correctness of theoretical analysis and the feasibility of the proposed Lyapunov control scheme. [ABSTRACT FROM AUTHOR]

The test principle of a new six-freedom tire test bench and analytical method of tire load were studied. Using multi-body dynamics theory and rotational transformation matrix, the actuator lengths of tire test conditions were obtained. Considering the directions of the actuator forces, the force sensor measurement, the actuator vector, and the rotational transformation of the tire force when there was a side slip angle, the tire forces in three directions were solved. Using the actuator force vector, the vector of each actuator arm and the space vector operation, the tire moments were solved. A simulation model of the tire test bench was built. The camber test and the side slip test were simulated. Simulation results show that the solution method of the actuators motion law is correct. The tire multi-condition test was simulated. Simulation results indicate that the solution method for the six components computation of tire load is feasible. [ABSTRACT FROM AUTHOR]

Su Shi and Li Dun who is the father of Li Zhi are enrolled as candidates in the highest imperial examination held in the palace under the emperor's supervision. Thanks to the friendship between Su Shi and his father, Li Zhi keeps company with Su Shi and becomes one of "Six adherents of Su Shi". Li Zhi is poverty-haunted in all his life, but Su Shi especially treats him as the son of his friend, and helps Li Zhi a lot in the aspects of life or official career or literature. Su Shi treats Li Zhi kindly. Li Zhi whose father is dead in childhood esteems Su Shi as his father, often going in and out of master's home gate. He was the most diligent disciple in all the adherents of Su Shi. Except that Li Zhi takes up with Su Shi, he also makes friends with Su Zhe and the sons of Su Shi. [ABSTRACT FROM AUTHOR]

[Introduction] Accurate estimation of the Li-ion batteries' State of Health (SoH) is essential for future intelligent battery management systems. To solve the problems of poor quality of data features and difficulties in adjusting model parameters, this study proposes a method for estimating the SoH of lithium batteries based on singular value fixed-order noise reduction and the sparrow search algorithm which can optimize the gated recurrent unit (GRU) neural network.[Method] Firstly, three indicators highly correlated with SoH decay were extracted from the battery charge and discharge data. Noise reduction was applied to the features using singular value decomposition techniques to improve their correlation with SoH. Next, using the sparrow search algorithm to optimize the model structure and parameters of the GRU neural network improve the accuracy of estimation of SoH. Finally, the battery data sets from Centre for Advanced Life Cycle Engineering (CALCE) were used to verify the validity of the proposed model. [Result] The experimental results show that the model proposed in this study applies to the battery SoH estimation, with a maximum root mean square error (RMSE) of only 0.018 4. After data noise reduction and algorithm optimization, the RMSE of the GRU model is reduced by 55.41% compared to the initial model. [Conclusion] The method proposed in this paper accurately estimates SoH and can be used as a reference for practical engineering applications.

Biomass activated carbon was prepared from discarded durian shell and longan shell by KOH chemical activation method, and their adsorption capacity of methylene blue (MB) in water was also investigated. The surface area test (BET), Fourier infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the prepared biomass activated carbon, and the effects of activated carbon amount, initial concentration of MB solution, reaction time, temperature and pH on the adsorption of MB were studied. Results indicated that the maximum adsorption capacity of durian shell (longan shell) activated carbon was 363 mg/g under the optimum conditions (initial MB solution concentration of 200 mg/L, carbon amount of 30 mg, pH8.0, 120 min). The specific surface area of durian shell and longan shell activated carbon were 999.63 m2/g and 1377.95 m2/g, respectively, and their average pore sizes were 2.13 nm and 2.20 nm, respectively. In addition, the surface of durian shell and longan shell activated carbon had a large number of pores and a certain laminar structure. The existence of these pores provides rich adsorption sites for activated carbon adsorption, and compared with commercially available activated carbon, it has a more dense pore structure and has a stronger adsorption capacity for methylene blue.

Science popularization work on earthquake prevention and disaster reduction should keep pace with the times, play a greater role in public opinion guidance, and take more responsibility in public opinion governance. In this paper we discuss that science popularization of earthquake prevention and disaster reduction plays an important role in guiding public opinion from two aspects. First, the hotspots of public opinion provide an opportunity for science popularization of earthquake prevention and disaster reduction. Second, the hotspots of public opinion provide contents for science popularization of earthquake prevention and disaster reduction. I put forward the public opinion guidance strategy of science popularization of earthquake prevention and disaster reduction from three aspects. First, reasonably set the science popularization agenda and take the initiative to guide public opinion; Second, consciously guide public opinion by means of new media communication technology; The third is to play a good “combination boxing” to form the greatest resultant force for public opinion guidance. In the hotspots of public opinion, we should actively do a good job of science popularization of earthquake prevention and disaster reduction, innovate communication forms and methods, skillfully set the agenda, cover the whole time and space, and participate in the whole society, build a benign public opinion field for the exchange of information between the government, the media and the public, enhance the public’s risk awareness and disaster prevention ability, and truly build a people’s defense line for risk prevention and control.

Objective: To establish a method for the determination of shrimp allergens in meat products by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods: Meat products (cooked ham, sausages and meatballs) with complex matrix components were selected as the detection target. The samples were extracted by ultrasonic in phosphate buffer solution (PBS) for 30 min, and acetonitrile was added to remove fat after centrifugation (10000 r/min, 15 ℃, 10 min). Finally, trypsin (1 mg/mL, 10 μL) was added to the sample diluents which had been mixed with internal peptide (2.5 μmol/L, 40 μL), and the enzymolysis process lasted 16 h at 37 ℃ before UPLC-MS/MS analysis. The samples were separated on a T3 column, and eluted by gradient elution with 0.1% formic acid aqueous solution and acetonitrile. The data was collected by multiple reaction monitoring (MRM) in positive ion mode, and quantified by internal standard method. Results: The method was used to determine the content of shrimp allergen in meat products, and the quantitative peptide had a good linear relationship with the determination coefficients 1.0000 in the range of 0.001~2.0 μmol/L. The limits of detection was 0.67 mg/kg, and the limits of quantification was 2.00 mg/kg. The recovery was 83.2%~104.5% and the precision was 2.63%~7.92% at three spiked levels. Conclusion: The method has the advantages of strong specificity, high sensitivity and good recovery. It was suitable for the screening and quantification of shrimp allergens in meat products.

With the rapid development of mobile services, big data, cloud services, and artificial intelligence, traditional network services cannot no longer meet the requirements of current network development and solve the problems of the resource allocation and scheduling ossification in the current network. Therefore, by using network virtualization technologies, we can provide the flexible network resource configuration information for users to reduce network cost and improve network resource efficiency. The required bandwidth resources of each virtual link are divided into different transmission line rate by employing mixed line rate splitting. We propose an optimized cost approach for Virtual Optical Network (VON) mapping based on mixed line rate. Simulation results show that the proposed optimized cost approach of VON mapping based on mixed line rate can achieve better optimization and balance in terms of the network cost, frequency slot occupation, the configuration of optical transponders, and optical regenerators.

With the rapid development of bulk commodities and electronic technology, the network information carried by the Internet delivers quickly to the market and the participants in it. Using search engines that equip with massive open-source data, we propose in this paper a prediction model of the price of bulk commodities, by constructing Internet concern indices from the key searching information. Due to the support vector regression (SVR) model with different kernel functions, we build a prediction model respectively for the single market of crude oil, copper and corn. In addition, considering the co-movement among commodity markets, we further present a model with Internet concerns in terms of multiple markets. Empirical results demonstrate that the Internet concerns present a significant Granger causality on the variation of market price. Meanwhile, taking into account the Internet concern indices as well as information from related markets can improve the prediction accuracy in a remarkable amount. [ABSTRACT FROM AUTHOR]

In order to provide a feasible lubrication means under starved condition， the gear transmission effect and the optimal oil-air parameters using oil-air lubrication are explored. Through the design of a five-level orthogonal test， the lubrication influence degree and tooth surface temperature， which are caused by oil supply， air supply and nozzle height， are analyzed under different speeds and load conditions. Then the optimal level setting and optimal solution of oil-gas parameters are obtained. These parameters are used in a comparative test between oil-air lubrication and splash lubrication. The results show that the air supply has the greatest influence on the oil-air lubrication effect， and there is an optimal air supply quantity； the influence of oil supply is the second. An appropriate increase is conducive to lubrication， but the improvement of lubrication effect is limited after exceeding a certain value； the nozzle height has the least influence； however， the height has the optimal value. To ensure safety， it should be put away from the gear properly. Oil-air lubrication has good cooling effect， and the transmission efficiency is better than splash lubrication under the same load condition. This research could provide technical guidance for the application of oil-air lubrication in gear transmission.

In order to study the variation law of kinematic parameters in the process of multi intersection and replacement in the process of human-machine carrying exoskeleton walking，a kinematic model of exoskeleton is established based on D-H coordinate system，and the kinematic expression in the process of walking is calculated by Newton Euler recursive formula. In order to realize the carrying movement between exoskeleton and human body，the parameters of joints in the process of human walking are measured and analyzed by displacement attitude sensor. Based on the exoskeleton carried by the third generation human-machine of Southwest Jiaotong University as research object，a virtual prototype is established in Adams environment，and a kinematic simulation of exoskeleton driven by human motion parameters is carried out. Taking the process of multi leg replacement as the starting point，the simulation results are analyzed. The results can provide a reliable basis for the measurement and control system driven by human-machine exoskeleton.

ObjectiveTo provide the scientific basis for the prevention and control of diarrheagenic Escherichia coli （DEC） infection， the epidemiological characteristics of DEC infection in Shanghai was identified.MethodsThe epidemiological information of the collected diarrhea cases and the DEC test results from 30 foodborne disease surveillance sentinel hospitals in Shanghai from 2018 to 2020 were analyzed by the descriptive epidemiological methods.ResultsAccording to the result of 13 672 infectious diarrhea cases and specimens， the positive rate of DEC was 5.71% （781/13 672）， mainly ETEC and EAEC. The highest positive rate of DEC was often associated with child below the age of 7 and the farmers， and the highest positive rate of DEC was occurred between July and September. Compared with other patients， the positive rate of DEC in patients with fever and no vomiting or diarrhea 3-9 times/d was significantly higher. The positive rate of DEC was relatively high in cases with suspected food category of fruit and its products.ConclusionETEC and EAEC were the main virulence genotyping of DEC in Shanghai， and the peak of DEC infection occurred in summer. Specific clinical symptoms could play as indications for clinical diagnosis and treatment. The supervision and management of catering service industry and street food should be improved， and the publicity and training of public food safety awareness and good food safety habits should be strengthened.

ObjectiveTo analyze the epidemiological features of foodborne disease outbreaks in Shanghai and to find the risk factors.MethodsWe collected the data of foodborne disease outbreaks occurred in Shanghai between 2010 and 2020， analyzed the characteristics of outbreaks， including time and geographic distribution， pathogenic factors and possible reasons caused outbreaks.ResultsBetween 2010 and 2020， there were 108 foodborne disease outbreaks with 1 736 cases， 45 inpatient cases and 1 death. May to September was the epidemic period， with about 64.81% of the outbreak occurrence. 39.81% outbreaks occurred in Pudong， Songjiang and Chongming Districts. Most outbreaks occurred in small restaurants （25%） and most foodborne cases were in staff canteen outbreaks （27.53%）. The main possible reasons caused outbreaks were improper food storage （19.44%）， cross-contamination （14.81%） and improper cooking （12.04%）. The major pathogenic factor was biological， caused 75.92% outbreaks and 77.59% cases. Methanol poisoning caused 1 death. The main contaminated food caused outbreaks was meat （17.59%）， multiple food （12.04%） and aquatic products （11.11%）.ConclusionThe foodborne disease outbreaks in Shanghai caused inpatient cases and death. We should pay more attention to foodborne disease outbreaks and we can control the risk factors by strengthening supervision and carrying out health education to reduce foodborne disease outbreaks.

Since establishment of cadre E-learning of China Earthquake Administration，its work has been widely recognized within the seismic system. However，there are also many issues we’ve seen during these years. The system needs to be re-integrated and optimized in accordance with the real operating conditions，so as to serve the students more effectively.