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Constitutive model of stone masonry is an important foundation and prerequisite for physical calculation and finite element numerical simulation of stone masonry. In order to further study the constitutive relationship of stone masonry under uniaxial compression, based on the theory of damage mechanics, the two-parameter Weibull distribution function was applied to reflect the damage variable, and its parameters were determined according to the characteristic conditions of the whole process of the stress-strain curve of stone masonry under uniaxial compression. The uniaxial compression damage constitutive model of stone masonry was derived and established, and the correctness of the constitutive model was verified by the existing test data. The constitutive model was compared with the typical masonry constitutive model. Finally, the finite element analysis of the existing stone masonry arch bridge test was carried out to verify the applicability of the constitutive model. The results show that the model is in good agreement with the uniaxial compression test results of existing stone masonry. The established model verifies the general law of masonry damage evolution and accords with the general trend of typical masonry constitutive model. The model can be applied to the finite element analysis and calculation of masonry structure with good applicability. [ABSTRACT FROM AUTHOR]

In order to investigate the residual degradation of pyrazolin in pears and provide theoretical basis for safe drug use in production, field experiments were conducted in Shandong, Hebei, Hubei, Gansu and Anhui provinces in 2020 to investigate the residual degradation of pyrazolin in pears. The results showed that the dissipation equations of pyraclostrobin in pear samples fit the first-order kinetics equation. The half-lives in pear was 9. 9 d. The pyraclostrobin was sprayed by dilution of 1 000 times and 500 times on pear for 2-6 times and samples were collected 7, 14 and 21 d after the last application. The final residue of pyraclostrobin in the pear was 0. 001-3. 601 mg/ kg. After applying high concentration, samples from 6 regions had exceeded the standard in some cases. After low-concentration application, except the samples collected at 7 and 14 days, the samples at 21 days exceed the standard. It was suggested that pesticide labeling requirements such as pesticide concentration, application times and pre-harvest interval should be strictly controlled when applying pesticide on pears, and the application times should not be blindly increased to avoid excessive standard. [ABSTRACT FROM AUTHOR]

Presently, the practical teaching system for chemistry and chemical engineering students faces challenges such as a weak theoretical foundation, a disconnect between theory and practice, and a mismatch between knowledge and innovative skill application. To address these issues, a binary combination strategy integrating theory-engineering and research-teaching is proposed, aligning with emerging engineering education paradigms. This approach allows for a more comprehensive and reinforced knowledge system, achieved by merging theory with practice. Both real and virtual training methods are employed to enhance experimental skills. Furthermore, amalgamating scientific research with industry-focused education elevates the practical proficiency of students. Investigating this holistic approach to practical education, tailored to societal demands and talent growth, offers a more robust method for cultivating innovative and skilled graduates in the fields of chemistry and chemical engineering. [ABSTRACT FROM AUTHOR]

Buckwheat is the major food crop in high altitude areas such as Liangshan district, Sichuan province, China. In order to explore the cold resistance of buckwheat and screen excellent buckwheat germplasm resources adapted to Liangshan district, 5 common buckwheat (Fagopyrum esculentum Moench.) and 13 Tartary buckwheat [Fagopyrum tataricum (L.) Gaertn. ], the most extensive varieties and landrace, were used to evaluate the cold resistance during seed germination stage at 4℃(low temperature condition) and 22℃(control condition). Seven indices related to germination and growth were measured, including radicle length, germination rate and germination potential. Comprehensive cold resistance was reflected by subordinate function analysis, principal component analysis and cluster analysis. The results showed that under low temperature conditions, the seed germination of all buckwheat materials was delayed and the germination rate was retarded. Compared with Tartary buckwheat, seven germination and growth indexes of common buckwheat maintained a higher level, indicating that common buckwheat was more tolerant under low temperature environment. The comprehensive evaluation of the membership function results suggested that Jiuzhaigou common buckwheat had the strongest low temperature tolerance ability at the germination stage, followed by Pintian No.3, whereas Xiqiao No.6 was the most sensitive to low temperature. [ABSTRACT FROM AUTHOR]

Objective To analyze the serological markers and surgical indicators associated with biliary complications after orthotopic liver transplantation, explore their influencing factors and predictive indicators. Methods A retrospective analysis was performed for the clinical data of 101 patients who underwent orthotopic liver transplantation in Renmin Hospital of Wuhan University from January 2016 to June 2022, according to the presence or absence of biliary complication (BC) at 6 months after surgery, they were divided into BC group with 21 patients and non-BC group with 80 patients.The t-test or the Mann-Whitney U test was used for comparison of continuous data between groups, and the chi-square test was used for comparison of categorical data between groups.Univariate and multivariate Logistic regression analyses were performed, and the receiver operating characteristic (ROC) curve was used to evaluate the predictive performance of combined indicators. Results Among the 101 patients, 21(20.8%) experienced BC.The multivariate Logistic regression analysis showed that MELD score (odds ratio[OR]=0.134, 95% confidence interval[CI]: 0.031-0.590, P=0.008), SⅡ/Alb (OR=1.415, 95%CI: 1.181-1.696, P=0.001), and plasma transfusion volume (OR=1.001, 95%CI: 1.000-1.002, P=0.032) were independent risk factors for the development of BC in patients after liver transplantation.MELD score, SⅡ/Alb, plasma transfusion volume, MELD+SⅡ/Alb, and MELD+SⅡ/Alb+plasma transfusion volume had an area under the ROC curve of 0.712, 0.870, 0.712, 0.900, and 0.918, respectively, in predicting BC after liver transplantation. Conclusion SⅡ/Alb, plasma transfusion volume and MELD score are independent risk fators for BC after liver transplantation.The combination of three indicators has good predictive value and clinical guiding significance for BC after liver transplantation. [ABSTRACT FROM AUTHOR]

Gaomiao site is an important agricultural site of the middle and late Neolithic Age in Yuanjiang River basin, Hunan Province. Since 1991, Gaomiao site has been excavated three times and a lot of agricultural remains have been unearthed, which is the key to revealing the origin of prehistoric civilization and the evolution of agriculture in the Yuanjiang River basin, including four stages of embryonic, foundation, development and mature period. The historical, artistic, scientific, social, and cultural values of this site have provided the important prerequisite and foundation for scientific planning and construction of archaeological parks, as well as for the protection of large sites and heritage tourism. [ABSTRACT FROM AUTHOR]

An accurate and rapid identification of species is one of the most important parts of freshwater fish pre-treatment. However, deep learning-based freshwater fish classification cannot quantitatively describe the feature parameters of fish, due to the complicated feature extraction. This study aims to propose a deep learning-based fish feature point detection and freshwater fish classification. Firstly, an image acquisition device was built to acquire the images of five freshwater fish species: bream, bighead carp, grass carp, silver carp, and common carp. Secondly, the data enhancement was performed on the original images. LabelMe software was also used to label 20 feature points of the fish body, in order to construct a freshwater fish feature point detection dataset. The feature point of freshwater fish was detected using an improved AlexNet feature point detection model with the convolutional neural networks (CNN). The improved AlexNet model also adjusted the network structure of the traditional model, in order to accommodate the feature point detection task by the modified convolutional kernel size, the removal of the local response normalization layer, the addition of batch normalization layer, and the replacement of the loss function. The Euclidean distance between feature points was extracted as the feature value using the coordinates of the feature points. Feature vectors were constructed. Fisher discriminant analysis was used to identify the species of freshwater fish. A series of ablation experiments were conducted on the improved AlexNet model to clarify the impact of different improvement schemes on model performance. The results showed that the improved schemes were beneficial to improve the training efficiency and performance of the model. The average value of normalized mean error (NME) of the improved AlexNet model on the test set was 0.0099, the failure rate (FR) at thresholds of 0.02 and 0.03 were 2.50% and 0.83%, and the average detection time was 0.037 s, indicating the better accuracy and error distribution. The number of parameters and floating-point operations per second (FLOPs) of the improved AlexNet model were smaller than those of the VGG16 model. The test set detection was also better than that of the VGG16 model, compared with different feature extraction models. Although the number of parameters and FLOPs of the improved AlexNet model was larger, the average NME and the FR were lower than that of the MobileNetV2 model. The recognition accuracy of 98.0% was achieved in the freshwater fish species recognition using the model and Fisher discriminant analysis for five freshwater fish species. The average recognition time of a single image was 0.368s. The feature point detection model can be expected to detect the feature points of five species of freshwater fish with high accuracy. The finding can also facilitate freshwater fish species identification, size detection, and fish segmentation. The freshwater fish species identification using feature point detection and Fisher's discriminant analysis can lay the foundation for the development of an automated freshwater fish classification device. [ABSTRACT FROM AUTHOR]

Rural tourism is a vigorous drive force to the development of rural economy, and an important power to lead the rural revitalization strategy in China as well. After the Pandemic of COVID-19, the demand for rural tourism products and quality continues to expand. However, during the rapid development, rural tourism showed mismatch between supply and demand. This paper took the case of Kunshan City in Jiangsu Province, based on the data of tourist market investment, using the IPA analytical method and the gap model of service quality, tried to find out the problems and countermeasures in re-matching of supply and demand in Kunshan's rural tourism industry, especially from the supply-side. This paper constructed the logical frame‐ work of supply-demand matching governance policy of rural tourism based on China's Rural Re‐ vitalization strategy. The research result can provide reference to the promotion of the quality for China's rural tourism development. [ABSTRACT FROM AUTHOR]

Objective To investigate the risk factors of infection after hepatectomy for liver cancer, and to establish and validate a risk prediction model. Methods The clinical data of 167 patients with primary liver cancer who underwent hepatectomy in People's Hospital of Wuhan University from January 2020 to March 2022 were retrospectively collected. All patients were divided into postoperative infection group (n=28) and non-infection group (n=139) according to whether postoperative infection complications occurred. The t-test or 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. Univariate analysis and logistic regression analysis were used to screen the risk factors of infection after hepatectomy for hepatocellular carcinoma, and a nomogram risk prediction model for postoperative infection was established. All patients were randomly divided into training cohort (n=119) and the validation cohort (n=48) according to the ratio of 7∶ 3, the Bootstrap method was used for internal validation of the model, and the model calibration curve and ROC curve were used to evaluate the calibration and discrimination of the nomogram model. Results Postoperative infection occurred in 28 of 167 patients (16.8%). Logistic regression analysis showed that diabetes, CONUT score ≥4 points, preoperative NLR, operation time, intraoperative blood loss, and drainage tube placement time > 7 d were independent risk factors for infection after hepatectomy for liver cancer (all P < 0.05). Based on the nomogram constructed from the above six risk factors, the area under the ROC curve of the training cohort and the validation cohort was 0.848, and 0.853, respectively. The calibration curve of the nomogram model shows that the predicted value is basically consistent with the actual observed value, indicating that the accuracy of the nomogram model prediction is better. Conclusion The individualized nomogram risk prediction model based on diabetes, CONUT score ≥4 points, preoperative NLR, operation time, intraoperative blood loss, and drainage tube placement time > 7 d has good predictive performance and has high predictive value for high-risk patients. [ABSTRACT FROM AUTHOR]

The experiment was to screen the shared DEGs of important brain tissues related to heat stress in broilers and explore their molecular mechanisms. Two sets of gene chip data sets of chicken brain and hypothalamus processed by heat stress were obtained from GEO database, and bioinformatics data were mined again. The results showed that 32 DEGs shared by important brain tissues related to heat stress were screened, including 27 significantly up-regulated genes and five significantly down-regulated genes. Through the analysis of GO and KEGG, the above genes are mainly involved in seveen biological processes and three KEGG pathways. Used STRING database and Cytoscape software to construct protein interaction network, there were 16 nodes and 102 proteins interacting. The first to seventh genes were screened as differentially expressed up-regulated genes due to GC, FGG, FGA, FGB, PLG, APOB and FABP1. The study indicates that sharing DEGs may be related to damage and pathogenesis of different tissues or organs in broilers during heat stress. [ABSTRACT FROM AUTHOR]

Aiming at the problems of low calculation accuracy by using traditional bolt connection model and parameter identification of bolt structure dynamic model, the six parameter Iwan model was introduced to numerically solve the force displacement relationship equation and draw the nonlinear force displacement relationship curve of Iwan model. The universal testing machine tensile test and vibration experiment platform excitation test were combined to identify the parameters of the model and realize the model construction. The experimental results show that with the increase of bolt diameter, the macro sliding residual stiffness increases, and the energy dissipation of the model decreases. The research results can provide a reference for the design, analysis and calculation of bolt structure. [ABSTRACT FROM AUTHOR]

Tumor microenvironment is composed of tumor cells and their internal and external environment, and the components vary slightly between different types of tumor. Liver cancer microenvironment is a tumor-promoting microenvironment constructed by hepatoma cells and immune cells and can lead to the development, invasion, and metastasis of liver cancer by recruiting inflammatory cells, inhibiting antitumor immune response, promoting angiogenesis, and promoting drug resistance. This article discusses the characteristics of liver cancer microenvironment, the composition and role of liver cancer microenvironment, and the new advances in microenvironment-targeting therapy for liver cancer. [ABSTRACT FROM AUTHOR]

Objective To investigate the predictive value of heart rate-corrected QT (QTc) and heart rate-corrected Tp-Te (Tp-Tec) intervals combined with serum complement 1q/tumor necrosis factor-related protein 9 (CTRP9) levels for the development of ventricular arrhythmias (VA) after acute myocardial infarction (AMI). Methods A total of 156 patients with AMI were selected, VA occurred in 61 cases during hospitalization (VA group), and 95 cases (non-VA group) did not have VA. The QT and Tp-Te intervals were recorded on admission using a 12-lead ECG machine, and the QTc and Tp-Tec intervals were calculated. On the next day of admission, early morning fasting elbow venous blood was collected, centrifuged and serum was retained, and serum CTRP9 was measured by ELISA. We compared the general clinical data［including gender, age, BMI, smoking history, underlying diseases (hypertension, diabetes, hyperlipidemia)], disease-related data［including Killip classification on admission, left ventricular ejection fraction (LVEF) within 6 h after admission], laboratory examination data [including the four lipid items (TC, TG, HDL-C, LDL-C), blood creatinine (Scr), blood uric acid (UA), fasting plasma glucose (FPG) and serum CTRP9 level on the day after admission] and ECG examination data (including QTc, Tp-Tec interval) between the two groups. A multi-factor Logistic regression model was used to analyze the factors influencing the development of VA after AMI. Receiver operating characteristic (ROC) curves were used to analyze the predictive value of QTc, Tp-Tec intervals and serum CTRP9 levels in the development of VA after AMI. Results Compared with the non-VA group, the QTc and Tp-Tec intervals were significantly prolonged and serum CTRP9 levels were significantly lower in the VA group (all P<0. 05). No significant differences were found in the general clinical data and blood lipid, FPG, or Scr between the two groups (all P>0. 05). The ratio of Killip grade >Ⅱ in the VA group was higher than that in the non-VA group, while the LVEF was lower than that in the non-VA group (both P<0. 05). UA was higher in the VA group than in the non-VA group (P<0. 05). Multi-factor Logistic regression analysis showed that UA, QTc interval and Tp-Tec interval were all independent risk factors for the development of VA after AMI, while CTRP9 was an independent protective factor (all P<0. 05). ROC curve analysis showed that the area under the curve (AUC) for QTc and Tp-Tec intervals combined with serum CTRP9 levels in predicting VA after AMI was significantly higher than that of QTc interval, Tp-Tec interval, QTc interval + Tp-Tec interval, and CTRP9 in predicting VA after AMI (all P<0. 01). Conclusions Patients with VA after AMI had significantly longer QTc and Tp-Tec intervals and significantly lower serum CTRP9 levels. QTc and Tp-Tec intervals were independent risk factors for the development of VA after AMI, while CTRP9 was its independent protective factor. QTc, Tp-Tec intervals and serum CTRP9 levels all had some predictive value for the development of VA after AMI, but QTc and Tp-Tec intervals combined with serum CTRP9 levels had significantly higher predictive value for the development of VA after AMI. [ABSTRACT FROM AUTHOR]

Currently, multiple difficulties exist in clinical liver transplantation, such as shortage of donor liver, increasing quantity of patients waiting for liver transplantation and lack of matching donors, etc. Some children and adult patients have little chance of undergoing liver transplantation, which also limits the development of liver transplantation. In this context, split liver transplantation emerges, in which 1 donor liver can be applied to 2 or even more recipients. It may effectively increase the utilization rate of donor liver and alleviate the shortage of donor liver. With the development of split liver transplantation, the survival rate of split liver transplantation is comparable to that of total liver transplantation. Multiple transplantation centers have routinely adopted split liver transplantation. In this article, the development of split liver transplantation, the selection and matching of donors and recipients, the split and reconstruction techniques of donor liver and postoperative complications were reviewed, aiming to provide reference for subsequent development of split liver transplantation in clinical practice and increase the chance of liver transplantation for more patients diagnosed with end-stage liver diseases. [ABSTRACT FROM AUTHOR]

Feeding has been one of the most cost sources in fish farming so far. Artificial and mechanized feeding has been the most two widely-applied approaches to fish feeding in China. However, both feeding cannot be cost saving, due mainly to the amount of feed always depends on the experience rather than the real hunger situation of fish. Once the feed is superfluous, it is likely to the water contamination in many cases. It is necessary to appropriately adjust the amount of feed, according to the timely feeding information. As a result, a more flexible feeding has been a high demand to control the feed amount, according to the changes in fish behavior, in order to effectively reduce costs for more benefits. Intelligent feeding has been partially realized, whether via the detected information from the feeding process through various sensors, or via the developed predicting models as a feeding guideline for the decision-making. However, there are still great challenges to realizing completely intelligent feeding. However, the predicted information depends mainly on the complex farming environment and uncertain fish behavior. In this review, the most technical applications were categorized in the fish intelligent feeding over the recent decades, including fish feeding behavior, visually intelligent feed detection, acoustics, sensor, and biological model technology. Several types of commonly-used fish feeders were determined, including the gravity drop, pneumatic conveying, centrifugal throwing, and hydraulic conveying types. A better performance was achieved to avoid the labor costs and feed wasting, if the feeder was precisely selected to fit well the actual breeding operation, according to the various fish types or breeding modes. Some aspects of the feeder still need to be improved for the goal of complete intelligence. More advanced techniques can be required to meet the future requirements of the feeder in the long-distance precise transmission for large-scale fish farming, specifically including average feeding and wide-range feeding. By contrast, an accurate and reliable feeding can be achieved for the feeder in the factory intensive farming mode, with emphasis on the small-size design and technical revolution. Furthermore, there is also some change from the timer and quantitative feeding to intelligent feeding in machines. Finally, a systematic investigation was made to summarize the national and international research on the specific application scenarios and basic components of intelligent feeding systems. It indicated that the signal transmission and control system were dominated in the most intelligent machines of fish feeding, where the input data was generally collected from the farming environment and fish behavior in practice. The document analysis on intelligent feeding demonstrated that the instant behavior of fish was usually identified to guide the feeding operation under the experimental condition in fish farming. Yet, there was still something to do better: 1) Some exogenous factors can pose some elusive impacts on the actual feeding operation, such as the environmental fluctuations or human activities; 2) The feeding decision-making models can be required to upgrade or modify for the wide universality suitable for the more types of scenarios and fish; 3) The computing equipment can be more powerful to promote more reliable data sampling. In conclusion, the main purpose of an intelligent feeding system can be to fit much better with the various feeding situations, whether different fish types or different breeding modes. As such, a much more accurate judgment can be achieved to take more variables into the comprehensive consideration. Therefore, it is a promising potential way to combine more available disciplines like Aquaculture, Engineering, and Computer Science, or incorporate more accessible information, such as images, sounds, growth patterns, and biological characteristics. The multidisciplinary or multimedia fusing entity can greatly contribute to the fish feeding system for fully complete intelligence in the near future. [ABSTRACT FROM AUTHOR]

For improving the classification accuracy of high-resolution remote sensing imagery, an accurate and automatic land cover classification convolutional neural network (LCC-CNN) for high resolution remote sensing imagery based on deep learning is proposed. The training dataset is constructed by GF-2 and BJ-2 image. The LCCCNN is designed with different sizes of dilated convolution in extracting multiscale features from remote sensing imagery. A novel loss function is designed for distinguishing the fuzzy boundary among different land cover classification regions. With the structure of encoder-decoder, LCC-CNN export pixel-level classification result, the experiments show that the overall classification accuracy, IOU, and Kappa coefficient of LCC-CNN are 87. 17%, 0. 773 2, and 0. 829 1. Compared with the existing approaches, such as SVM and decision tree, the accuracy, IOU, and Kappa coefficient are improved by 8%, 10%, and 11%. The experiments also prove that LCC-CNN has strong applicability for high-resolution image classification without designing classification features and parameters. [ABSTRACT FROM AUTHOR]

Sustainable agricultural mechanization has been one of the most important strategies for the decision-making and operations in the management of crop production. An accurate and rapid evaluation can greatly contribute to promoting the quality of sustainable agricultural mechanization in China. However, many complex and changing factors are confined to the sustainable agricultural mechanization in recent years. Generally, four dimensions can be maintained for agricultural mechanization: the social and economic benefits, the operation level, the impact on the resources and environment, and the level of the agricultural engineering industry. In this study, a systematic evaluation was made on the influencing factors in the sustainable agricultural mechanization in Hubei Province of China using the combination of Decision-Making Trial and Evaluation Laboratory (DEMATEL) and Interpretive Structure Modeling (ISM). An evaluation index system was constructed to determine 13 indicators of sustainable agricultural mechanization, four parts of which were pressure (including the positive and negative factors), state, influence, and response, according to the hierarchical connections. A comparison was also made on the specific data of the 13 secondary indicators in the study area from 2004 to 2020. The quantitative data showed that the fuzzy DEMATEL-ISM performed better to integrate the subjective and objective opinions of influence indicators, further to determine the main influencing factors of sustainable agricultural mechanization. A pressure-state-impact-response model was selected to assess the index system of t sustainable agricultural mechanization. It was found that the pressure factors were the most significant driving factors in agricultural mechanization, accounting for more than 40% of the weights in the evaluation index system, followed by the State, and the lowest were Impact and Response. The results show that the economic factors were the most important development factors, while, the environmental factors dramatically increased to be the influencing factors. Furthermore, the input-output, scientific and technological factors of agricultural mechanization were also comprehensively evaluated in the index system. More importantly, the evaluation result showed that the sustainable agricultural mechanization in the study area was positive and orderly developed as a whole over the past ten years. Among them, the positive driving factors of the pressure and state-related indicators increased significantly, such as the economics, the agricultural engineering industry, as well as agricultural science and technology. The maximum contribution rate was attributed to the economic benefits and capacity development in sustainable agriculture manufacturing. The pressure part was remained basically stable, indicating the impact of labor reduction on agricultural mechanization. The agricultural machinery cost factors were basically maintained a small range of fluctuations. The adverse factors of the energy environment posed a great effect on income, output growth, and agricultural mechanization. At the first time, the response part was much higher than the pressure and impact parts, indicating the ever-increasing investment in the control of sustainable development. Much attention can be paid to the concept of sustainable development for the decision-making on the increasing investment, further offering greater opportunities and challenges for the sustainable agricultural mechanization in the end, some recommendations were also proposed for the future development of agricultural mechanization. [ABSTRACT FROM AUTHOR]

作为近年来快速发展的一种新的起搏治疗方法,希浦系统起搏相比传统的右心室起 搏,更符合生理性起搏的定义。 本文报告 1 例房颤伴三度房室阻滞患者植入单腔起搏器治疗, 术中发现并夺获右束支电位;将起搏器电极置于右束支区域起搏后,QRS 波时限为 90 ms,达 峰时间 37 ms,较术前无明显改变。 此例经右束支选择性起搏 QRS 波时限几乎正常,有利于维 持心电活动的同步性、保护左心功能。 [ABSTRACT FROM AUTHOR]

[Objective] The extraction and change monitoring of cultivated land information is one of the hotspots of remote sensing application research. Northern Guangdong is the main grain base of Guangdong Province, and is the key area of cultivated land change monitoring by business management departments.[Method] In the present paper, using GF-2 and Sentinel-2 remote sensing images, combined with the phenological period of late rice in the study area, the vegetation index, humidity index, brightness index, color index and texture features were extracted for multi-scale segmentation, and the multi-scale image of paddy field extraction was constructed. The index difference image and time series multi feature difference image were classified to extract the paddy field area and evaluate the results.[Result]（i) The highest extraction accuracy of paddy field in time series multi feature difference image was 0.98,and the minimum difference between paddy field area and late rice sowing area was 240.05 hm2,and the best paddy field extraction effect was based on time series multi feature difference image;（ii）The difference of index feature needed to use the key phenological characteristics of crops and combine with multi-scale segmentation of image to improve the accuracy of paddy field extraction;（iii）The machine forest method has faster operation speed and higher classification accuracy in data classification with high dimensional features. [Conclusion] The research of the paper is to explore the method of high-resolution remote sensing in rapid and accurate updating of cultivated land information, which can provide support for the application of cultivated land management business. [ABSTRACT FROM AUTHOR]

In order to improve the accuracy rate of state diagnosis of rolling bearing based on time domain signals, a novel diagnosis system which combined significance sequence of vibration signals and machine learning was proposed. Firstly, the residual spectral of the signal was obtained by subtracting the logarithmic amplitude spectrum from the mean logarithmic amplitude spectrum which was acquired by analyzing the normalized vibration signals in frequency domain. Then, the spectral residual of the vibration signals was mapped back to the time domain by inverse Fourier transform to obtain the significance sequence. Finally, the state diagnosis model was used to classify the significance sequence to achieve fault detection of the bearing state. The experiment results indicate that the significant sequence can effectively improve the classification accuracy rate comparing with the original vibration signal, especially for the vibration signal mixed with the different signal noise ratio (SNR) of Gaussian white noise, such as mixed with white Gaussian noise of-6 dB, using support vector machine (SVM) or convolution neural network (CNN) as the state diagnosis model respectively, the significance sequence can respectively improve the accuracy rate of state diagnosis by 9% and 10.75%. What’s more, this method can also effectively shorten the training time of the network model. [ABSTRACT FROM AUTHOR]

The fracture mechanics for thermoelectric materials with equilateral triangle holes subjected to uniform electric current densities and uniform energy fluxes at infinity was studied by means of the complex variable method. The analytic expressions of temperature fields and stress fields were obtained under the boundary conditions of electric insulation and thermal insulation. Effects of the triangle size, the applied electric current density and the energy flux on the thermoelectric material were analyzed. The results show that, the variations of the current density and the triangle size have obvious influences on the annular energy flux, the annular stress and the annular heat flux. [ABSTRACT FROM AUTHOR]

The purpose of this project is to guide students in independently designing experiments based on problemoriented approach, taking a commonplace phenomenon (white flocs formed during laundry) as the starting point. The measurement of surface tension is integrated into the process of exploring the underlying chemical principles of daily life phenomena, and an exploratory experimental model that follows a “problem identification-practical explorationtextbook consolidation” framework is established by combining a diverse array of techniques, thereby reinforcing the students’ understanding of colloid and interface chemistry. The revised experiment offers richer content, greater challenges, enhanced comprehensiveness, and increased engagement, effectively fostering students’ abilities to analyze and solve problems and nurturing their inquisitive thinking. Furthermore, this experiment ensures a high degree of safety, ease of operation, and requires no specialized equipment, making it highly suitable for undergraduate instructional labs. [ABSTRACT FROM AUTHOR]

The structure of medical compression nebulizer plays a decisive role in the atomized inhalation treatment of respiratory diseases. The effects of the nozzle structure, gas flow rate and liquid channel width of the medical compression nebulizer on the atomization effect were studied by the volume of fluid-discrete particle model (VOF-DPM). The results show that the kinetic energy of the droplets after compression atomization and the proportion of droplet size below 5 μm are proportional to the gas flow rate. With the increase of the width of the liquid channel, the kinetic energy of the droplets will increase after atomization, but the proportion of droplet size below 5 μm will be relatively reduced. The use of conical crushing baffle structure can not only improve the kinetic energy of the droplets after atomization, but also increase the proportion of droplet size below 5 μm by about 5% ~ 7% compared with the original. By changing the shape of the chemical solution crushing baffle, the proportion of droplet diameter below 5 μm, and the kinetic energy of the droplet after atomization of the chemical solution are increased, which improves the atomization effect of the atomizer. These analysis results have guiding significance for the performance characterization and structural optimization design of subsequent medical compression nebulizers. [ABSTRACT FROM AUTHOR]

Objective: To retrospectively compare the clinical efficacy of transoral oral vestibular approach and transthoracic breast approach in the treatment of papillary thyroid microcarcinoma (PTMC). Methods: The clinical data of 141 patients with unilateral PTMC who were admitted to Department of Thyroid and Vascular Surgery, Nanhai Hospital Affiliated to Southern Medical University from January 2019 to June 2021 were retrospectively analyzed. The patients were divided into group A ( n = 83 transthoracic breast approach) and group B (n=58, transoral oral vestibular approach) according to the different approaches. The operation-related indicators, traumatic stress indicators, cosmetic satisfaction, complications and follow-up prognosis were compared in the two groups. Results: The operation time in the group B was longer than that in the group A, the number of central lymph nodes dissected was more than that in the group A, the drainage volume on 1 d after operation and intraoperative blood loss were less than those in the group A, the neck VAS score on 1 d after operation and the total length of incision were less than those in the group A, and the postoperative hospital stay was shorter than that in the group A (P < 0.05) . There were no significant differences in white blood cell count (WBC), C-reactive protein (CRP), prostaglandin E2(PGE) and cortisol (Cor) between the two groups before operation and 2 d after operation (P > 0.05) . 0.2d after operation, the levels of WBC, PGE2, CRP and Cor in the two groups were significantly higher than those before operation, and the differences were statistically significant (P < 0.05) . The cosmetic satisfaction rate in the group B was higher than that in the group A ( p < 0 . 05). There was no difference in the incidence of complications in the two groups (P>0.05). At 1-year postoperative follow-up, the rates of death, recurrence, and cervical lymph node metastasis were 0 in both groups, with no differences between the two groups (P > 0.05) Conclusion: Transoral oral vestibular approach can achieve the same surgical effect as transthoracic breast approach in the treatment of PTMC. However, transoral oral vestibular approach removes more central lymph nodes, has less trauma, less postoperative pain, and has a higher cosmetic satisfaction. [ABSTRACT FROM AUTHOR]

【Objective】Land use is comprehensively affected by natural conditions and socio-economic factors, and the study of time series changes in land use is conducive to providing a scientific basis for the rational use of urban land resources.【Method】Landsat satellite remote sensing images of six periods were selected at five-year intervals for land use classification from 1995 to 2020, and the land use structure, dynamics and land use transfer in Guangzhou were analyzed. The influence intensity and interaction mechanism of various factors on land use change in different periods were discussed by using geographic detectors. 【Result】（i） Under the scenario of long time series（1995-2020） urban land use change, geodetector model could analyze the factors of urban land use change in different periods and reveal its change rules.（ii） From 1995 to 2020, the construction land in Guangzhou showed a trend of ‘stable-slow increase-sharp increase’, while the cultivated land showed a trend of ‘slow decrease-stable-substantial decrease’, and the transferred area mainly came from cultivated land and forest land. The forest land and grassland showed a monotonous decreasing trend, mainly transferred out as construction land and forest land. The water area fluctuated up and down, mainly from cultivated land. Unused land was gradually reduced, mainly converted into construction land.（iii）In different periods from 1995 to 2020, the influence of driving factors of land use change in Guangzhou was different. Among them, the influence of socioeconomic factors on land use change was higher than that of physical geography.（iv） In different periods from 1995 to 2020, the q value of the interaction factor was higher than that of the single factor q value, which showed that the interaction between the factors was two-factor enhancement. 【Conclusion】The impacts of human activities on land use change are obviously different in spatial distribution. The overlapping of multiple factors will aggravate the conflict of land use. Reducing the impact of human activities on the environment is an important way to achieve sustainable development. [ABSTRACT FROM AUTHOR]

Populational number of fish is of great significance in the intelligent aquaculture. An accurate and rapid target detection has been always obtained from the underwater images. Much attention is still paid on the single target during underwater fish detection so far. However, the overlapping target is largely limited to the applicative scenes. In this work, an overlapping fish detection model was proposed using image enhancement and an improved Faster-RCNN network, named after CP-Faster-RCNN. First, 15 healthy grass carps were fed in a test tank for 15 days, where the images of fish movement were collected by the equipped underwater camera. The total 2 077 available images were filtered to serve as the dataset for the modelling. The training, test, and validation set were divided, according to the rate of 6:2:2, respectively. In the training set, all recognized fishes in each image were labelled by the rectangle bounding boxes via a labelImg tool. Next, three most commonly-used detection models (YOLOv3-spp, SSD300, and YOLOv5x6), as well as the new proposed model (CP-Faster-RCNN) were trained using the training and test set, and then were verified by the validation set. Among them, the CP-Faster-RCNN model was optimized for such the overlapping fishes in the images. Hence, some improvements were made using the original Faster-RCNN model. The details were as follows. 1) The MSRCR combined with the adaptive median filtering was adapted to improve the definition of underwater images; 2) The ResNeXt101 network was served as the backbone network to enhance the feature extraction capability of the model; 3) A specific bilinear path aggregation network (Bi-PANet) with the Convolution Block Attention Module (CBAM) attention mechanism was designed to fully use the multi-scale feature maps, which was effectively reduced the interference of background information. 4) The PAM clustering was chosen to optimize the scale and number of initial anchors of the network, which was used to speed up the convergence of the model; 5) The Non-Maximum Suppression was replaced by the Soft Non-Maximum Suppression, in order to reduce the missed detection for the overlapping objects. The results showed that the mean Average Precision (mAP) values of CP-Faster-RCNN were 32.9, 12.3, and 6.7 percentage higher than those of YOLOv3-spp, SSD300, and YOLOv5x6, respectively, indicating the best performance of detection. Besides, 300 extra images were randomly selected from the validation set to test the actual performance of the four models. Statistical analysis demonstrated that there was the different detection accuracy at the different number of overlapping fishes in clusters. Once the number was from 2 to 5, the mAPs of CP-Faster-RCNN decreased orderly, which were 80.4%, 75.6%, 65.1%, and 55.6%, respectively. More importantly, the mAPs of CP-Faster-RCNN was rather higher than that of other three models in the same way, indicating the better suitable performance in the scenes of overlapping fishes. Last, five ablation tests were carried out to investigate the specific effects of five improvements, where the mAP was the index of assessment. It was found that the mAP of the CP-Faster-RCNN was 76.8%, which was the totally 8.4 percentage increase than that of the original Faster-RCNN network. The backbone network was replaced for the 5.7 percentage mAP increase, due to the more substantially complex model. Meantime, the pre-processing of dataset was also offered a 0.9 percentage increase of mAP. The other three improvements for the Faster-RCNN posed the positive impacts on the model complexity. All improvements were promoted the more accurate detection for the model. Therefore, the improved model can be expected to achieve the much more accurate fish detection, especially for the overlapping fish images in the complex underwater backgrounds. [ABSTRACT FROM AUTHOR]

Objective·To screen the potential hub genes associated with myocardial ischemia-reperfusion injury (MIRI) in mice by bioinformatics analysis based on gene expression omnibus (GEO) database. Methods·The mouse MIRI data sets GSE61592, GSE83472 and GSE160516 were obtained from GEO database. The differentially expressed genes (DEGs) in each data set were screened by limma package, and then robust DEGs were screened by robust sorting integration (RRA) method. The protein-protein interaction (PPI) network of robust DEGs was constructed, and the submodules and hub genes in the PPI network were screened. The clusterProfiler package was used to analyze the robust DEGs, the most important submodule genes and hub genes by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Eighteen male C57BL/6 J mice aged 6 ‒ 8 weeks were randomly divided into sham group and MIRI group, 9 mice each group. The MIRI model was constructed by left anterior descending coronary artery ligation for 30 min ischemia and 24 h reperfusion, and the mRNA expression of hub genes was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Results·RRA method identified 294 robust DEGs in three data sets. In PPI network, a total of 14 sub-modules were screened, of which module 1 was the most important and 17 hub genes were found. GO and KEGG analysis showed that the robust DEGs, module 1 genes, and the hub genes were mainly involved in regulating the migration of inflammatory cells, the activity of chemokines and cytokines and their receptors, Toll-like receptors and other biological function and signaling pathways. RT-qPCR results showed that compared with the sham group, the expressions of chemokine (C-C motif) ligand 4 (Ccl4), Ccl6, Ccl7, chemokine (C-X-C motif) receptor 4 (Cxcr4), chemokine (C-C motif) receptor 2 (Ccr2), signal-regulatory protein β1 (Sirpb1), low affinity immunoglobulin gamma Fc region receptor Ⅱb (Fcgr2b), leukocyte surface antigen CD53 (Cd53), arachidonate 5-lipoxygenase activating protein (Alox5ap), myeloid differentiation primary response gene 88 (Myd88), macrophage scavenger receptor 1 (Msr1), matrix metallopeptidase 14 (Mmp14), triggering receptor expressed on myeloid cells 2 (Trem2) and leupaxin (Lpxn) were up-regulated in the myocardium of the MIRI group, but there was no difference in low affinity immunoglobulin gamma Fc region receptor Ⅲ (Fcgr3), complement C1q subcomponent subunit B (C1qb) and a disintegrin and metalloproteinase domain-containing protein 8 (Adam8). By reviewing the literatures, Trem2, Lpxn, Cd53, Alox5ap, Sirpb1 and Fcgr2b were not reported to participate in MIRI. Conclusion·This study has unearthed 6 potential hub genes for MIRI in mice, and the results can provide new ideas and entry points for further exploring the molecular mechanism and therapeutic targets of MIRI. [ABSTRACT FROM AUTHOR]

The coastal waters along the northern Shandong Peninsula waters is rich in fishery resources, which is the passing fishing ground for economic organisms to enter the Bohai Sea to spawn and leave for winter. In recent years, overfishing and pollution have caused considerable damage to fishery resources there, and zooplankton has been adversely affected. Based on sampling data in this area from 2016 to 2017, the spatial and temporal distribution, structure community, dominant species and diversity indices of zooplankton community were analyzed. 39 species of zooplankton and 13 classes zooplankton larvae were record during the four surveys, which belonged to 11 phyla and most species were found in autumn. The dominant species had obvious seasonal change, Calanus sinicus, Labidocera bipinnata and Sagitta crassa were the main dominant species record, among them, Calanus sinicus was the dominant species in four surveys. Influenced by the Bolai coastal current, Yellow Sea warm current and Yellow Sea cold water mass, the seasonal variation of zooplankton abundance was obvious, with the highest abundance (147.1 ind·m–3) in spring and the lowest abundance (37.3 ind·m–3) in winter. The horizontal distribution of zooplankton abundance was uneven, with higher abundance in the western ocean near Zhifu Island in spring and autumn, while the concentration center located in the eastern ocean near Weihai in summer and winter. [ABSTRACT FROM AUTHOR]

In offshore fracturing operation, formulating a fracturing fluid with fresh water results in high transportation cost and long time of formulation. If seawater is used to formulate the fracturing fluid, a large amount of chelating agents which crosslink in alkaline environment shall be used, and this results in high material cost, while the ability of the fracturing fluid formulated to resist high temperature may not be satisfactory. To solve this problem, an organic titanium zirconium crosslinking agent is stepwise synthesized with reactants tetra-isopropyl titanate and zirconium sulphate etc. Characterization of the reaction product with NMR and SEM (after precipitation of the crosslinking agent) shows that the crosslinking agent is an organic chelating agent. The particle sizes of the crosslinking agent are distributed in a range of 1 nm to 100 nm, as measured with dynamic and static synchronous laser scattering instrument, and this indicates that the crosslinking agent has excellent reactivity. This crosslinking agent can crosslink in neutral conditions, a good property for formulating fracturing fluids with high salinity waters such as seawater. The microstructure of the crosslinking product is a stable honeycomb-like hexagonal grid structure. With this organic titanium-zirconium crosslinking agent, the fracturing fluids formulated have better viscoelasticity than the fracturing fluids formulated with crosslinking agents containing only titanium. The high temperature resistance of the fracturing fluids formulated using the organic titanium-zirconium crosslinking agent is 180 ℃. Field application of this new crosslinking agent in formulating a fracturing fluid with seawater for fracturing a high temperature well of CNOOC in south China Sea has obtained good results [ABSTRACT FROM AUTHOR]

Objective To explore the relationship between C-reactive protein (CRP) and blood glucose in prediabetic population through a cohort study, and to explore whether grip strength can regulate the correlation. Methods Based on the China health and retirement longitudinal study (CHARLS), the middle-aged and elderly people who participated in the baseline survey (2011) and the follow-up survey (2015) were selected. Multiple Logistic regression model was used to analyze the relationship between CRP and pre-diabetic people who developed into diabetes or returned to normal blood glucose as well as the regulatory effect of grip strength. Results A total of 2 811 subjects were included in this study. During the follow-up period, 441 (15.7%) developed diabetes, 1 762 (62.7%) maintained the status of prediabetes, and 608 (21.6%) returned to normal blood glucose. After adjusting the covariates, the results of multiple Logistic regression showed that compared with CRP first quartile (Quartile 1), both CRP third quartile (Quartile 3) and fourth quartile (Quartile 4) increased the risk of diabetes, their OR values and 95%CI being 1.63 (1.18-2.24) and 1.67 (1.14-2.17), respectively, and the probability of returning to normal blood glucose was reduced by 32% in Quartile 4 group. In the low grip strength group, the risk of developing diabetes in the Quartile 3 and Quartile 4 groups was 1.80 (95%CI:1.13-2.87) and 2.04 (95%CI:1.29-3.23) times higher than that in the Quartile1 group, while the Quartile 4 group reduced the chance of returning to normal blood sugar by 41%, but the association was not observed in the high grip strength group. Conclusion CRP is closely related to the change of blood glucose in pre-diabetic population, but high grip strength can regulate this correlation. [ABSTRACT FROM AUTHOR]

[Objectives] The paper aimed to investigate the inhibitory effect of 5 °C low temperature treatment on seed germination of celery and its regulatory mechanism. [Methods] The seeds of Shanghai yellow heart' were treated at 5 and 20 °C to explore the germination, gibberellin(GA) and abscisic acid(ABA) contents, the dynamic changes of key genes expression in metabolic pathways, and the dynamic changes of starch and soluble sugar contents. [Results]5 °C low temperature treatment significantly inhibited the seed germination rate, seedling emergence rate, relative water absorption and embryo growth of celery, while 20 °C treatment could rapidly promote the seed germination. And after the seeds treated at 5 °C for 15 days were transferred to 20 °C (T5-20 treatment), the seeds could quickly recover their germination vitality, which indicated that 5 °C low temperature did not cause irreversible damage to the seeds. The results of seed vitality staining also indicated that low temperature did not cause damage to the embryo structure. Low temperature at 5 °C also markedly inhibited the synthesis of GA during germination, and the expression of related metabolism and downstream genes was also markedly inhibited, while 20°C treatment significantly promoted the synthesis of GA, and the high expression of GA3ox1 gene in seeds treated at 20 °C and T5-20 meant that it might play a key role in the synthesis of GA. ABA content showed a dynamic change in 5 °C treatment, but GA/ABA showed a downward trend in adults. The expression of the ABA degrading gene CYP707A1 had a significant negative correlation with ABA content in the middle and late stages of seed germination 5 °C treatment. In addition, 5 °C also significantly inhibited the sugar metabolism capacity of celery seeds. The starch content of celery seeds treated at 5 °C was significantly higher than that treated at 20 °C, but the soluble sugar content was significantly lower than that treated at 20 °C. [Conclusions] Low temperature at 5 °C induced secondary dormancy of celery seeds. GA/ABA might be an with low temperature. in important signal of celery seeds' response to ambient temperature, and GA3ox1 and CYP707A1 were potential key genes to cope. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma（HCC）is the most common type of primary liver cancer. The boom in novel immunotherapies has topped the most remarkable progress in HCC treatment in the past decade. As members of the immune system，natural killer（NK） cells play a vital role in anti⁃tumor immunity. Chimeric antigen receptor（CAR）⁃NK cell therapy is a new type of tumor immunotherapy， in which NK cells are genetically engineered to specifically recognize tumor⁃associated antigens to produce more precise and efficient anti ⁃tumor efficacy. Focusing on CAR targets and related immune checkpoints，this review summarizes the challenges and possible solutions for CAR⁃NK in HCC treatment. Furthermore，it discusses potential strategies for boosting the efficacy of CAR⁃NK. [ABSTRACT FROM AUTHOR]

目的　观察小剂量艾司氯胺酮联合右美托咪定在阻塞性睡眠呼吸暂停低通气综合征 (OSAHS) 患者清醒 纤维支气管镜引导气管插管 (AFOI) 中的应用效果。方法　全麻下行悬雍垂腭咽成形术的OSAHS患者60例, 按随 机数字表法分为对照组和观察组各30例。对照组静脉注射舒芬太尼, 观察组静脉注射艾司氯胺酮, 两组均同时予 右美托咪定泵注, 右美负荷量泵注完毕即开始纤维支气管镜引导插管。分别于入室安静10 min时 (T0 ) 、纤维支气管 镜置入鼻腔时 (T1 ) 、纤维支气管镜置入声门时 (T2 ) 、气管导管置入声门时 (T3 ) 记录两组患者心率 (HR) 、平均动脉压 (MAP) 、呼吸频率 (RR) 、脉搏血氧饱和度 (SpO2 ) 、Ramsay镇静评分 (RSS) 及T3时点呼气末二氧化碳分压 (PETCO2 ), 记 录两组患者插管时间、插管条件评分、患者舒适度评分、操作医师满意度评分、不良反应发生情况。结果　与同组T0 时点比较, 对照组T1 、T2时点HR、MAP下降, T1 ～T3时点RR、SpO2下降; 观察组T2时点RR、SpO2下降 (P均<0. 05) 。与 对照组同时点比较, 观察组T1 、T2 时HR升高 (P均<0. 05), T1 ～T3时MAP、RR、SpO2升高 (P均<0. 05) 。观察组T3时点 PETCO2低于对照组; 与同组 T0 时点比较, 两组 T1 ～T3时点 RSS评分均升高 (P均<0. 05) ; 两组同时点 RSS评分比较差 异均无统计学意义。两组插管时间、插管条件、患者舒适度和操作医师满意度差异均无统计学意义, 观察组低血压、 低氧血症及插管知晓发生率低于对照组 (P均<0. 05) 。结论　小剂量艾司氯胺酮联合右美托咪定在OSAHS患者清 醒气管插管中镇静效果较好, 且应用安全。 [ABSTRACT FROM AUTHOR]

Objective To explore the clinical value of Hydrogen proton magnetic resonance spectroscopy (¹H-MRS) in the early diagnosis of Parkinson's disease (PD). Methods A total of 45 patients with early PD (PD group) and 40 healthy volunteers (control group) admitted to the Outpatient and Inpatient Departments of Yancheng First People's Hospital from May 2017 to May 2020 were selected as the research subjects. All subjects were examined by ¹H-MRS, and the ratios of N-acetylaspartic acid (NAA)/choline (Cho), NAA/creatine (Cr) and Cho/Cr in lentiform nucleus, globus pallidus, thalamus and substantia nigra of all subjects were compared and analyzed. Results The ratios of NAA/Cho, NAA/Cr in lenticular nucleus, globus pallidus and substantia nigra, and the ratios of NAA/Cho, NAA/Cr and Cho/Cr of the thalamus in the PD group were significantly lower than those in the control group, and the differences were statistically significant (P<0. 05). In the PD group, the ratios of NAA/Cho and NAA/Cr in lenticular nucleus, globus pallidus and substantia nigra, as well as the ratios of NAA/Cho, NAA/Cr and Cho/Cr in thalamus were negatively correlated with the Unified Parkinson's Disease Rating Scale (UPDRS) scores (P <0. 05). The area under curve (AUC) of the receiver operating characteristic curve of the NAA/Cho ratio in the lenticular nucleus, globus pallidus, thalamus 'and substantia nigra was 0. 796,0. 708, 0. 709 and 0. 723, respectively. The AUC of the NAA/Cr ratio was 0. 726,0. 726,0. 744 and 0. 913, respectively. The AUC of the Cho/Cr ratio was 0. 579, 0. 509,0. 637 and 0. 531, respectively. Conclusion It can be combined with' H-MRS on the peak changes of NAA, Cho and Cr in the lenticular nucleus, globus pallidus, thalamus and substantia nigra and the changes in the ratio of the three to diagnose early PD. ' H-MRS may have good diagnostic value for early PD. [ABSTRACT FROM AUTHOR]

Based on the maximum daily electric load of Changsha City from 2018 to 2020 and the daily meteorological data during the same period, variation pattern of the maximum daily electric load and the holiday/weekend effect on the maximum daily electric load are statistically analyzed. The trend method is used to isolate the weather sensitive load, and the correlation between the weather sensitive load and the meteorological elements is analyzed. The electric load is simulated and predicted by SVM method and the multiple linear regression method. The results show that there are two peaks in the maximum daily electric load of Changsha City in one year, which occur in summer and winter. The maximum daily electric load in Changsha shows an overall growth trend. The holiday/weekend effect of the maximum daily electric load is not obvious. In spring and autumn, the correlation between weather sensitive load and meteorological factors is relatively poor. In summer and winter, temperature is the most important meteorological factor affecting meteorological load. The SVM method has a better simulation effect on the maximum daily electric load of Changsha City, and the addition of comprehensive meteorological indexes makes the simulation result better. [ABSTRACT FROM AUTHOR]

Fresh water products is one of the most valuable nutrients in nature, due to the high protein content rich in amino acids and vitamins. Among them, the Asian swamp eel (Monopterus albus) is one of the most widely distributed freshwater fish in China. However, a great challenge is still remained in the aquatic products processing, due mainly to the manual sectioning with high labor intensity, low work efficiency and low safety, particularly for the Monopterus albus and pond loach (Misgurnus anguillicaudatus) freshwater fish. Taking the fresh Monopterus albus as the test object, this study aims to design and develop a new sectioning device, according to the fish habits and body characteristics. A series of experiments were carried out to determine the fish body clamping and force characteristics, in order to analyze the fish feeding, body positioning and clamping behavior. The sectioning device was composed of the tilting hopper, fish inlet channel, counter roller, and blade disc. Specifically, the structural parameters of the sectioning device were set, where the fish inlet channel was 180 mm long and the diameter at the fish inlet was 28 mm; the edge of the roller was serrated with a wide top and narrow bottom; and the diameter of the blade disc was 114 mm. The influencing factors of the sectioning were selected as the diameter of the roller, the initial gap of the roller, the rotation of the roller, and the exposed height of the blade disc. An optimization test was carried out with the impact factors of roller diameter, roller initial gap, roller rotation speed, and the exposed height of the blade disc as the influencing factors, and the acceptability score of the sectioning as the evaluation index. The results showed that the better clamping performance of the fish body was achieved in the roller diameter of 180 mm. The highest acceptability score of the abdominal section was obtained in the roller initial gap of 8 mm. Furthermore, the clamping performance was significantly better at the high roller rotation speed than that at the low one in the constant roller diameter. The acceptability score of the abdominal section increased gradually with the increase of the exposed height of the fish body support plate by the blade disc. The orthogonal test showed that the highest acceptability score of abdominal dissection was obtained, when the roller rotation rate was 180 r/min, the exposed height of the blade disc to the support surface was 22 mm, and the roller initial gap was 8 mm. The generality test showed that the new section device can be expected to better apply to freshwater fish with different body sizes, fully meeting the actual processing requirements. The optimal production capacity reached 24.3 pieces/min. The finding can also provide a strong reference to developing sectioning devices for freshwater fish. [ABSTRACT FROM AUTHOR]

As a substitute of protein, single cell protein (SCP) is a high value-added biological product. It has a good development prospect that single cell protein are transformed into animal feed products by using different organic nitrogen sources such as greenhouse gases and waste biomass and inorganic nitrogen sources in the environment. The paper reviews the production of bacteria and the production enhancement techniques, the raw materials and the application of single-cell protein in detail, to provide a reference for the application and development of SCP in the feed industry. [ABSTRACT FROM AUTHOR]

In order to solve the problem that the existing cardiopulmonary resuscitation（CPR）machines could not be adaptively adjusted according to the various situations of patients, an intelligent CPR machine based on the impedance control was designed. Firstly, the transmission scheme and structure of the CPR machine were introduced. The planned process of closed cardiac massage by using the force compliance of impedance control was introduced. The proposed machine could adjust the pressing movement according to the current situation of the patient. Then, the pumping effect and potential fracture risk of each closed cardiac massage were monitored. Based on the pumping effect and fracture risk, a fuzzy controller was designed. The fuzzy control was used for the adjustment of impedance parameters, and the trajectory of the pressing process was generated by the impedance controller. Finally, semi-physical experiments were carried out using the medical human body model and the mathematical model built by the computer. The compression effects of intelligent cardiopulmonary resuscitation machine and traditional cardiopulmonary resuscitation machine were compared. The experimental results show that the compression depth of the intelligent CPR machine reaches 5 cm to 7 cm. Comparing with the traditional CPR machine, the intelligent CPR machine increases the PETCO2 by 4.58 mmHg; on the premise of restoring the patient’s ability to breathe spontaneously, the proposed CPR machine can reduce the harm of closed cardiac massage to the patient and ensure safety. [ABSTRACT FROM AUTHOR]

Objective To evaluate the difference of Pressure Support vs T-Piece vs Automatic Tube Compensation Ventilation Strategies during Spontaneous Breathing Trials on lung aeration. Methods Sixty-nine cases of mechanically ventilated patients who were prepared to undergo the first spontaneous breathing trial （SBT） in EICU of an affiliated Hospital of Medical University from June 2020 to January 2021 were included. They were randomly divided into T-Piece group, Pressure Support Ventilation （PSV） group and Automatic Tube Compensation （ATC） group for 30 minutes of SBT. After successful SBT, the tracheal intubation was removed within 24 hours. We observed the patients’ Lung Ultrasound Scores （LUS） with ultrasound before the beginning of SBT （T0）, at the end of SBT （T1） and 30 minutes after extubation （T2） in all patients. Results At the end of SBT, the LUS of the three groups were not significantly different （P > 0.05）. The LUS of patients in T-Piece, there was no significant difference in the changes from T1 to T2 （P > 0.05）. The LUS of patients in the PSV group and ATC group increased from T1 to T2 （P < 0.05）. Conclusion SBT strategy with pressure support is helpful for patients to pass SBT and ensure lung ventilation during SBT, however, T-tube SBT seems to be a better predictor of lung ventilation after extubation. [ABSTRACT FROM AUTHOR]

Ion-induced secondary electron emission (SEE) was the fundamental physical process for low temperature plasmas.The dielectric surface charge played an important role in the process of SEE,which affects the dynamics of plasma discharge.Compared to the previous model which simplifies the electronic structure and the parameter of surface charges, a more accurate method based on Auger neutralization and the density functional theory (DFT) model was applied to calculate the secondary electron emission coefficient (SEEC) of MgO with accumulated surface charge in the atmospheric pressure helium dielectric barrier discharge (DBD) with nitrogen impurities.It discussed the influence of SEEC considering dielectric surface charge on the spatiotemporal characteristics of DBD.In order to observe the effect of dielectric surface charge on the secondary electron emission process, it introduced the peak-leveled voltage which carry little dielectric surface charge during the discharge process to compare with the sinusoidal voltage.The simulation results showed that when the SEE process considering the dielectric surface charge, the current waveform done not change obviously under the peak-leveled voltage.However, under the sinusoidal voltage, the phase of the discharge moment was advanced, the current amplitude was significantly reduced and the spatial distribution of electrons was more dispersed.The result further verifies the effectiveness of the DFT model in our work, and lays a theoretical foundation for the further study of the physical process of DBD discharge. [ABSTRACT FROM AUTHOR]

Phosphorus has been widely used as the essential component in the fertilizer and feed of agriculture, but it is a non-renewable resource. Biogas slurry rich in phosphorus can serve as a recyclable agricultural waste resource. Phosphorus recovery from the biogas slurry can be widely expected to realize nutrient management and utilization, particularly for the green and sustainable development of circular agriculture. Therefore, it is necessary to recover the phosphate from the biogas slurry for sustainable agriculture. Alternatively, adsorption is one of the main technologies in nutrient recovery. Different types of adsorbents have been developed to capture phosphate, including biochar, metal-based materials, minerals, functionalized silica, and various modified wastes. Among them, the layered double oxides (LDO) can often be coupled with the biochar-based materials, which are taken as an adsorbent and as a host substance, due to the multiple parent materials. The introduction of biochar materials can improve the recovery rate of phosphorus in a cost-saving way. More importantly, the biochar-based materials with unique pores and abundant surface functional groups can greatly contribute to the pore structure and surface functional group density of composites, where the ions can be highly concentrated in recycled materials. Herein, a new composite adsorbent of biochar-LDO was proposed to recover the nutrient elements from the biogas slurry using adsorption, in order to effectively recover the phosphorus for better resource utilization. The synthesis temperature of composite material was also evaluated to improve the adsorption performance of phosphorus. It was found that the layered bimetallic oxide (Mg/La0.1-LDO) synthesized by the quantitative control of magnesium and lanthanum presented rich interlayer ions and nanoparticles in the early stage, indicating an excellent performance in the phosphorus adsorption. However, the dispersion of nanomaterials in the solution and the high cost of raw materials relatively reduced the value of material recycling and application. Therefore, the straw of crops (rice and corn) was added to fix and strengthen the Mg/La0.1-LDO, where the biochar-magnesium/lanthanum bimetal oxide nanocomposite (BC-LDO) was prepared for the phosphorus recovery from biogas slurry using the co-pyrolysis at different temperatures (400, 500 and 600 ). The resulting BC ℃ ℃ ℃ -LDO was then characterized to determine the recovery capacity by the SEM-EDX/TEM/FTIR/XRD techniques. The results showed that the pyrolysis at a high temperature (600 ℃) was more conducive to the fixation of nanoparticles on the straw biochar (6YBC-LDO), which was rich in meso- and micro-porous materials. The particle size of the nanocomposite decreased significantly (between 12 and 20 nm), with the increase in pyrolysis temperature. These nanocomposites were also easier to combine with the phosphate to form LaPO4 precipitation and Mg3(PO4)2 inner-sphere complexation. According to the Langmuir equation, the maximum phosphate uptake of 6YBC-LDO was estimated to be 366.39 mg/g, which was significantly higher than that of 5YBC-LDO and 4YBC-LDO. The kinetic investigation showed that the 6YBC-LDO effectively adsorbed the high phosphorus (69 mg/g) within 30 min, and strongly enriched the straw biochar, indicating an excellent phosphate adsorbent. The 6YBC-Mg/La0.1-LDO presented a high selective adsorption capacity for the phosphate, which was reused many times after desorption. The 6YBC-LDO rapidly removed more than 90% phosphate in the biogas slurry, where the phosphate concentration was reduced to less than 8.25 mg/L within 1 h. Consequently, the 6YBC-LDO has an excellent application prospect in the nutrient recovery from the biogas slurry. [ABSTRACT FROM AUTHOR]

In this paper, wavelet analysis and Kalman filtering were combined to process the deformation data of Wuluwati dam, and the results of wavelet Decomposition and reconstruction and wavelet packet decomposition and reconstruction were compared and analyzed. Most of the high-frequency noise and gross errors in the original observation signal were filtered in advance and then used the model combined with wavelet and wavelet packet and standard Kalman filter to process the data again. The results show that the model further improves the reliability and accuracy of the data. According to the analysis of engineering examples, the data residuals of wavelet packet decomposition and reconstruction are small, closer to the original measured value, and have higher application value. The wavelet packet Kalman combination model is better than the wavelet and Kalman combination model for improving the accuracy of dam monitoring data analysis. [ABSTRACT FROM AUTHOR]

Aiming at the water injection development problems of low permeability reservoir in Nanpu oilfield, such as increasing pressure of water injection wells, decreasing water absorption index and decreasing liquid production of production wells, the natural core and injected water of low permeability reservoir in Nanpu 13-52 well are studied to evaluate the damage degree of reservoir permeability caused by factors such as reservoir sensitivity, water injection scaling and solid particles blockage. Sensitivity damage experiments show that the degree of reservoir water sensitivity damage is moderately strong; the variation of ion content of injected water at normal temperature and formation temperature indicates that the injected water is extremely unstable and there is a large amount of scale precipitation under the formation temperature ; the permeability damage rate increased linearly with the increase of solid content and median particle size in injected water, and the permeability damage rate of injected water due to solid particle blockage reached 64.84%. According to the comprehensive study, reservoir water sensitivity, scale formation of injected water and solid particle blockage are the main reasons for water injection difficulties in low-permeability reservoirs in Jidong oilfield. and solid phase particle blockage is the main factor of injection water damaging low permeability reservoirs. [ABSTRACT FROM AUTHOR]

In a wind tunnel test, the tail model support system of cantilever beam structure will produce vibration under the wind load, which may threaten test safety and affect test results. In order to suppress the vibration of the model and support system, an active vibration control method is studied and applied. Among them, the actuator of suppression system adopts piezoelectric material, and the control system is based on adaptive internal model control algorithm. This paper analyzes the structure and working principle of the adaptive internal model control algorithm, and introduces the model parameter identification in training mode and the adaptive adjustment process of control parameters in experimental mode. A control system based on the adaptive internal model control algorithm is established. A signal generator is used to simulate the excitation of the system on the ground simulation platform. The control algorithm is verified as the input of the control system. Combined with the wind tunnel test, the control effect of the system is verified under actual conditions. The results show that the active vibration control system based on adaptive internal model control algorithm can reduce the vibration by more than 70%. [ABSTRACT FROM AUTHOR]

Objective To identify the chemical components of Guanxin H formula, and explore its mechanism in the treatment of acute myocardial infarction. Methods In this study, the components of Guanxin H formula were identified w让h high performance liquid chromatography-mass spectrometrytandem mass spectrometry (HPLC-MS/MS), the targets of the detected components were screened by searching the TCMSP database, and the disease targets were screened by searching the GeneCards and OMIM databases. Then STRING was applied to build the network of PPI, and Bioconductor database was used to perform GO and KEGG enrichment analysis, and Cytoscape software was used to build the drug・ component-target-pathway-disease network diagram・ Core targets were then obtained by calculating topological parameters・ Finally, detected components and targets were identified by molecular docking・ Results Five chemical components of Guanxin H formula were detected, i・ e. ferulic acid, tanshinol, paeoniflorin, protocatechualdehyde, and hydroxysafflor yellow A (HSYA)・ Nine key targets were screened, including CHRM1, CHRM2, CHRM3, PTGS1, ADRA1A, PLAU, GABRA1, AR and IL6, with the neuroactive ligand-receptor interaction pathway, calcium signaling pathway, cholinergic synapse pathway, and actin cytoskeleton signaling pathway involved・ Molecular docking showed good binding activity between the detected components and CHRM1, and the molecular conformation was stable・ Conclusion Five quality control components of Guanxin H formula could be detected relatively quickly and accurately by HPLC-MS/MS・ By binding with CHRM1, the components of Guanxin H seem to protect cardiac myocytes through regulating the neuroactive ligand-receptor interaction pathway, calcium signaling pathway, cholinergic synapse pathway, and actin cytoskeleton signaling pathway, thus inhibiting oxidative stress, inflammatory damage and apoptosis after myocardial infarction. This study potentially provides a new idea and direction for further exploring the mechanism of Guanxin H formula in the treatment of acute myocardial infarction. However, further experimental proof is still needed to determine whether Guanxin H formula plays a role through the four pathways above, and to clarify the main targets and interaction between pathways. [ABSTRACT FROM AUTHOR]