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Aiming at the problems of unbalanced inter-modal optimization and inadequate fusion of multimodal features in multimodal sentiment analysis, a multimodal sentiment analysis model combining dynamic gradient mechanism and multi-view co-attention mechanism (DG-MCM) is proposed, which can effectively mine single-modal representation and fully integrate multimodal information. Firstly, the model uses pre-trained model BERT (bidirectional encoder representation from transformers) and stacked long short-term memory (SLSTM) to learn the features of text, audio and video, and proposes a dynamic gradient mechanism. By monitoring the contribution difference and learning speed of each mode, the feature learning of each mode is assisted. Secondly, the features of different modes obtained are fused using the multi-view co-attention mechanism. By projecting every two modes into multiple spaces for interaction, more adequate fusion features are obtained. Finally, fusion features and single-modal features are spliced together for sentiment prediction. Experimental results on CMU-MOSI and CMU-MOSEI datasets show that this model can fully learn information between single mode and different modes, and effectively improve the accuracy of multimodal sentiment analysis.

The nuclear thermal propulsion (NTP) boasts advantages such as high specific impulse, substantial thrust, and extended operating time, giving it a clear edge in deep space exploration and orbital maneuvers. To fully harness the potential of NTP, a comprehensive system performance analysis is crucial to ensure reliability and efficiency under various operational conditions. This study provided an overview of the historical development and current status of nuclear thermal propulsion system analysis programs, both nationally and internationally. It also conducted an in-depth analysis of programs utilized in projects such as NERVA and SNTP. Building on an examination of historical international program advancements and current research requirements, system performance analysis is categorized into three primary components:steady-state performance design and optimization, steady-state off-design performance analysis, and transient performance analysis. Based on the independently developed program for analyzing nuclear engine systems (PANES) at Institute of Nuclear and New Energy Technology, Tsinghua University, an integrated NTP system analysis program framework based on "flow network-heat network" was proposed. The one-dimensional flow network model employed a concept similar to the staggered grid commonly used in computational fluid dynamics (CFD). It separately handled the momentum conservation equation in the resistance/inertia segment and the continuity and energy conservation equations in the capacitance segment. The thermal network model was solved based on the solid energy equation considering heat capacity. Coupled calculations of the thermal network and flow network were achieved by considering heat exchange in the capacitance segment of the flow network. Specifically, a point reactor model based on backward Euler (BE) or Crank-Nicolson (CN) time discretization formats was established to facilitate the calculation of power produce processes. To enhance the understanding and optimization of turbine performance, a turbine model was developed, employing iterative methods to determine mass flow based on turbine inlet parameters, pressure ratios, and characteristic curves. Additionally, to accurately simulate centrifugal pump behavior, a centrifugal pump model based on Suter curves was implemented. The integration of these models provides a comprehensive approach for considering and effectively designing and optimizing the performance of turbine and pump components within the NTP system. This work lays a crucial foundation for further research and application of NTP system design methods, paving the way for future advancements in space exploration and offering exciting prospects for upcoming space missions.

The performance of space nuclear reactors and spacecraft is significantly influenced by the size and mass of shield, therefore shielding design and optimization are crucial for the development of space nuclear power systems. In this paper, shielding design and optimization process was proposed, and the effectiveness was verified through an optimized shielding design for the Jupiter Icy Moons Orbiter (JIMO) reactor. Building upon the open lattice reactor concept of the JIMO project, the neutronic design of the JIMO reactor was supplemented. The shielding design and optimization for the reactor employed a layered combination of beryllium (Be), boron carbide (B4C), tungsten (W), and lithium hydride (LiH). Considering the radial distribution of radiation dose, the Monte Carlo method was utilized to compute the neutron flux and the photon dose at the payload. Additionally, the neutron dose at the leading edge of the LiH was taken into account. Given the computational cost associated with the Monte Carlo method, the stepwise optimization approach was proposed after the analysis of the coupled transport characteristics of neutrons and photons and the shielding design principles. The stepwise optimization and analysis revealed several key findings. Firstly, the multi-layer Be-B4C configuration, compared to the single-layer Be plus single-layer B4C arrangement, effectively reduces reflected neutrons, thereby diminishing the mass required for photon shielding material. This reduction results from a decrease in the secondary photons generated within the leading-edge structural materials. Secondly, due to the lower photon doses at the outer edge resulting from the strong penetration ability of photons, the mass of the photon shielding material can be reduced by decreasing the photon shielding radius. Thirdly, a shielding configuration with a Be to B4C thickness ratio of 7:3 demonstrates excellent shielding effectiveness while maintaining a relatively small mass. Finally, placing W at 30 cm from the shielding leading edge not only reduces the photon shielding radius but also decreases the generation of the secondary photons, leading to an optimal shielding mass. The optimized shielding demonstrates equivalent radiation attenuation capabilities to the JIMO shielding, encompassing the attenuation of neutron flux and photon dose at the payload and neutron absorption dose at the leading edge of LiH. Simultaneously, the shielding mass is reduced by 98.41 kg. This underscores the effectiveness of the shielding optimization process. The developed shield and the associated design process have the potential to serve as a valuable reference for future shielding design and optimization for space nuclear reactors.

Object detection is one of the hottest directions in the field of computer vision. In order to further improve the performance of the object detection algorithm, a dynamic intersection over union loss (DYIoU Loss) based on the intersection over union (IoU) is proposed to solve the limitations of the position loss function in the training process. The relationship between the internal components of the position loss function is fully considered, and the weight of the position loss components can be given dynamically at different stages of the training to more specifically constrain the network. This enables the network to optimize different parts more effectively during the early, middle, and late stages of training to better align with the characteristics of the object detection task. In addition, in order to solve the deficiency of the feature fusion stage in the object detection network, deformable convolution is applied to the PAN (path aggregation network) structure, and a deformable path aggregation network neck (DePAN Neck) that can be plugged in is designed to improve the model’s ability to fuse multi-scale features and improve its detection performance on small objects. The above methods are applied to YOLOv6 models of YOLOv6-N, YOLOv6-T and YOLOv6-S sizes, and rich experiments are designed on the COCO2017 dataset to validate the effectiveness. The results show an average increase of 2.0 percentage points in the average precision (mAP).

Objective To study the effect of miR-499a-5p on injury induced by chemical hypoxia of pheochromocytoma cell(PC12). Methods PC12 cells were divided into control group, hypoxia group (treated with CoCl2 for 24 h), hypoxia+miR-NC or miR-mimic groups. Cell viability was detected by MTT assay; the expression of miR-499a-5p was detected by RT-qPCR; lactate dehydrogenase (LDH) activity was detected by kit; apoptosis was detected by flow cytometry; the expression of phosphatase and tensin homolog (PTEN) protein was detected by Western blot. The luciferase reporter gene was used to detect whether Pten was a direct target of miR-499a-5p. Results Compared with control group, the cell viability and miR-499a-5p expression decreased (P＜0.01 or P＜0.001), LDH activity and apoptosis increased (P＜0.01 or P＜0.001) in hypoxia group. Over-expression of miR-499a-5p enhanced survival rate and inhibited apoptosis of PC12 cells under hypoxia (P＜0.05 or P＜0.01). Pten was a direct target of miR-499a-5p. Conclusions miR-499a-5p alleviates hypoxic injury of PC12 cells through targeting at Pten.

Al-Zn-Mg series aluminum alloys have important applications in aerospace, transportation etc, for their excellent properties of low density and high strength. Further optimizing the microstructure to obtain higher mechanical properties and better corrosion resistance is the development direction of Al-Zn-Mg alloys. Microalloying has become an important means of improving the properties of aluminum alloys, owing to the limited space for alloy composition optimization and heat treatment processes improvement. The effects of microalloying elements on the mechanical properties, hot deformation behavior and corrosion resistance of Al-Zn-Mg alloys were briefly summarized, focusing on the different effects of the second phase particles formed by microalloying elements in different process stages, such as effectively refine grains and strongly hinder the movement of dislocations. The effects of pin grain boundaries, sub-grain boundaries and inhibiting recrystallization during hot deformation were discussed. The internal mechanism of improving the corrosion resistance of the alloy was explained. In addition, the further research direction of microalloying of Al-Zn-Mg aluminum alloy was prospected, understanding the interaction mechanism of microalloying elements and dual alloying-microalloying elements to realize the precise and accurate addition of microalloying elements will be one of the main research contents in the future. Clarifying the regulation effect of microalloying elements on deformation structures and dislocation configurations during hot working will provide a reference for improving the corrosion resistance of alloys.

Using SBAS-InSAR based on StaMPS and taking Antaibao Open-pit Coal Mine as research area, this paper carries out time series interferometry processing on 33 sentinel ascending and descending images, extracts ground deformation information of open pit coal mine for 7 months. According to SAR satellite imaging geometry, slant-range deformation information is decomposed, and cumulative deformation of open-pit coal mine in two-dimensional direction during data collection period is obtained. Deformation rate of open-pit coal mine is -258 mm/a. A large subsidence center is found in dump, and cumulative subsidence is 134 mm; large gradient deformation in decorrelation area is calculated by offset tracking technique. The combination of two techniques can better monitor deformation of open-pit coal mine at different gradients.

In this paper, tofu and plant ash were used as the main raw materials to prepare the plant ash culture tofu by ash culture, marinating and frying. The best formula of the plant ash culture tofu was determined by single factor and orthogonal experiment. The results showed that: the best formula of the plant ash culture tofu was as follows: the ash culture time of tofu was 6 days, adding 2.2% salt, 0.6% chili powder, 2% soy sauce, 1% sugar, 0.04% black pepper, 0.5% monosodium glutamate and 0.2% five spice powder to every 1000 milliliter soup. The prepared ash culture tofu has light soy sauce color, soft texture, moderate salty and spicy, and strong bean flavor. Compared with ordinary tofu, the hardness, elasticity, stickiness and chewiness of ash culture tofu were 5.17 times, 1.33 times, 6.24 times and 8.78 times of ordinary tofu, respectively.

As the lightest metal structural materials, magnesium and its alloys have great potential to achieve lightweight products in the future. However, magnesium has a high corrosion sensitivity, and the magnesium hydroxide film formed on the surface is loose and porous with little protection, which leads to its application being limited. How to improve the corrosion resistance of magnesium has become a worldwide problem that restricts its application. Alloying is one of the ways to radically improve the corrosion resistance of magnesium alloys. In this paper, the corrosion mechanisms of pure magnesium and the mechanisms of alloying elements on the corrosion performance of magnesium alloys are described in terms of the influence of alloying elements on the corrosion resistance of magnesium and its alloys. In addition, protection mechanisms produced by alloying elements on magnesium alloys were compiled, and the protection mechanisms and corresponding characteristics of beneficial elements on magnesium alloys were summarized. This can provide some reference for the development of new magnesium alloys and the improvement of the corrosion resistance of magnesium alloys. In addition, this paper contributes to a better understanding of the corrosion behavior of magnesium alloys. At present, there is no magnesium alloys can be as good as aluminum alloys or stainless steels corrosion resistance, so the development of corrosion-resistant magnesium alloys needs further research. This paper provides a theoretical basis for the interaction between elements in magnesium alloys, which can provide ideas for the development of new corrosion-resistant magnesium alloys. The synergy between the elements will have a significant impact on the design, process and performance of new corrosion resistant magnesium alloys, and as the research progresses, it is expected that new corrosion-resistant magnesium alloys similar to "stainless steel" will be constructed.

Objective Evaluate the learning outcoems of the flipped classroom teaching model applied to teaching of English case-discussion round for internal medicine in eight-year medical students. Methods Totally 88 eight-year clinical medical students of the Peking Union Medical College in 2019, applied the flipped classroom teaching mode in the internal medicine English case-discussion round. The mastery of knowledge was assessed by quiz before and after case-discussion round. The teaching effect was assessed by post-round feedback of five-score Likert Scale. Results The mastery of knowledge by pre self-learning are 29.3%, 37.3% and 17.3% of disease diagnosis and differential diagnosis, disease classification and degree, and treatment principles. Post-round the mastery can further achieved 84.8%, 60.9% and 45.7% respectively, through group discussions in class (P＜0.05). The average score of teaching feedback post-round was (4.01±1.02), the evaluation items with average scores ＞4 points accounted 66.7%. Conclusions The teaching mode of flipped classroom combined with small group learning can significantly improve learning outcomes as acknowledged by students.

Objective To explore the effect of the feedback of competency-based training and its evaluation in the Clinical Postdoctoral Program of Peking Union Medical College Hospital. Methods Taking 2018 clinical postdoctoral feedback and evaluation as the object of study, collecting feedback results with the 5-point Likert Scale and reviewing the descriptive comments, to discuss the application of feedback evaluation. Results 13 clinical departments were rated above 4 on average in “individualization” “degree of recognition” “preparation”. “Feedback skill” was rated 3.6. The skills of feedback needed an improvement. Conclusions The feedback evaluation system will contribute to the improvement of feedback and competency-based training quality, and further modification is needed.

Based on traditional processing methods, replacing rice vinegar with lactic acid, and then optimizing the hydrolysis process. The maximum degree of hydrolysis of the egg solution obtained by the optimal solution can reach 24.184%. On this basis, protease is used for enzymatic hydrolysis and various probiotics. When the bacteria were fermented, the maximum peptide content of the obtained sample could reach 1.526 mg/mL, which has obvious advantages over the traditional vinegar egg liquid and fermented egg liquid. It has been determined that the free amino acids in egg liquid after multiple hydrolysis are complete, and the content of inorganic elements such as calcium, iron, and zinc is high, and has good antioxidant capacity. The shell egg hydrolysis fermentation broth is sprayed and powdered, and seasoned and mixed to obtain a functional food with high calcium content, low cholesterol, rich in small molecule peptides, and good flavor.

Flame retardant expandable polystyrene foams were prepared by coating with melamine modified urea formaldehyde resin. The flame retardant system was based on ammonium polyphosphate, and the combination of three kinds of two-dimensional layered material and zinc borate was used as synergist. The influence of different flame retardants on fire resistance, smoke suppression and thermal stability was discussed. The experimental results show that the flame retardancy is significantly improved by the presence of expandable graphite and zinc borate with mass ratio of 2:1 and total additive amount of 24 phr. The limiting oxygen index of EPS foams is increased to 32.6%, with V-0 rating in UL-94 vertical burning test. The smoke density grade is decreased to 27.31. Compared with the sample containing only expandable graphite, the introduction of zinc borate enhances the strength of residue char from 14.3 to 86.1. Thermal analysis suggests that the thermal stability and char formation are improved by the presence of synergist. The residual char observation reveals that zinc borate is beneficial to form complete and integrated char layers with less crack and breakage.

Objective To explore the feasibility of using progression elevated gene-3 (PEG3) promoter, a tumor-specific promoter, to drive the specific expression of the reporter gene ferritin heavy chain 1 (FTH1) and the detection of FTH1 expression using in vitro magnetic resonance imaging (MRI) in bone marrow mesenchymal stem cells (MSCs) after malignant transformation. Methods A viral vector carrying the reporter gene FTH1 driven by PEG3 promoter was transfected into rat MSCs to obtain MSCs-PEG3-FTH1 cells, and the MSCs transfected with a viral vector carrying FTH1 driven by the CMV promoter (MSCs-CMV-FTH1 cells) and the MSCs without transfection served as the controls. The non-transfected MSCs, MSCs-PEG3-FTH1 cells, and MSCs-CMV-FTH1 cells were indirectly co-cultured with rat glioma C6 cells for 2 weeks to induce their malignant transformation (TMSCs, TMSCs-PEG3-FTH1 and TMSC-PEG3-FTH1 cells, respectively). The morphology, migration and proliferation, and the cell surface antigens CD29, CD34, CD45 and CD90 of the transformed cells were observed and analyzed, and their capacity of subcutaneous tumor formation was evaluated in nude mice. Western blotting, Prussian blue staining, transmission electron microscopy, and in vitro MRI were used to detect the changes in the expression of FTH1 gene in the cells after the transformation. Results Compared with MSCs, most of TMSCs were small in size with a spindle-like morphology and showed strong proliferation and migration abilities with increased expression of CD34 and CD45, decreased expression of CD90 (P < 0.05), and an ability of subcutaneous tumor formation in nude mice. Western blotting showed that FTH1 protein was not expressed or expressed at low levels in MSCs, MSCs-PEG3-FTH1 cells and TMSCs, while high FTH1 expression was detected in MSCs-CMV-FTH1, TMSCs-PEG3-FTH1 and TMSCs-CMV-FTH1 cells(P < 0.05). Prussian blue staining and transmission electron microscopy identified the presence of iron particles in MSCs-CMV-FTH1, TMSCs-PEG3-FTH1 and TMSCs-CMV-FTH1 cells, but not in MSCs, MSCs-PEG3-FTH1 cells or TMSCs. In vitro MRI showed obviously decreased T2 signal in TMSCs-PEG3-FTH1 cells as compared with MSCs-PEG3-FTH1 cells. Conclusion PEG3 promoter can drive the specific expression of FTH1 that allows MRI detection in rat MSCs after malignant transformation. cell transformation neoplastic

In view of importance of roof separation monitoring of mine roadway, the paper proposed a design scheme of monitoring system of roof separation. It gave structure and arrangement scheme of measured points and detailedly introduced hardware and software design of surrounding rock movement sensor which can measure displacement of roof separation. It also analyzed determination methods of position of roof separation and alarm threshold of displacement of roof separation. The actual test result showed that the system realizes real-time monitoring for displacement of roof separation with 2.5% measuring precision.

The factors of affecting crankshaft torsional fatigue strength and the causes of various torsional failure were analyzed by torsional fatigures test of crankshafts, and the corresponding improvement measures were put forward. It was pointed out that with the increase of engine explosion pressure, the torque of crankshafts increases accordingly, which leads to the increase of crankshaft torsional fatigue failures. The main torsional failure locations include pin journal oil hole, crank arm and pin journal bottom center of the crankshafts. The causes of failure are related to structural design, raw materials, machining, heat treatment and so on. The oil holes of pin journal are the most common part of torsional fatigue failures, and the crack sources are generally about 8~10 mm from the inner walls of oil holes to the journal surfaces. The torsional fatigue strength of crankshafts is more affected by induction hardening on the journal surfaces. The torsional fatigue strength of crankshaft reduces about 30% by surface induction hardening. The torsional fatigue strength of surface hardening crank shafts is increased more than 25% by polishing the internal surfaces of the oil holes. [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of injury time, postmortem interval (PMI) and postmortem storage temperature on mRNA expression of glycoprotein non-metastatic melanoma protein B (Gpnmb), and to establish a linear regression model between Gpnmb mRNA expression and injury time, to provide aimed at providing potential indexes for injury time estimation. Methods Test group SD rats were anesthetized and subjected to blunt contusion and randomly divided into 0 h, 4 h, 8 h, 12 h, 16 h, 20 h and 24 h groups after injury, with 18 rats in each group. After cervical dislocation, 6 rats in each group were collected and stored at 0°, 16° and 26°, respectively. The muscle tissue samples of quadriceps femoris injury were collected at 0 h, 12 h and 24 h postmortem at the same temperature. The grouping method and treatment method of the rats in the validation group were the same as above. The expression of Gpnmb mRNA in rat skeletal muscle was detected by RT-qPCR. The Pearson correlation coefficient was used to evaluate the correlation between Gpnmb mRNA expression and injury time, PMI, and postmortem storage temperature. SPSS 25.0 software was used to construct a linear regression model, and the validation group data was used for the back-substitution test. Results The expression of Gpnmb mRNA continued to increase with the prolongation of injury time, and the expression level was highly correlated with injury time (P<0.05), but had little correlation with PMI and postmortem storage temperature (P>0.05). The linear regression equation between injury time (y) and Gpnmb mRNA relative expression (x) was y=0.611 x+4.489. The back-substitution test proved that the prediction of the model was accurate. Conclusion The expression of Gpnmb mRNA is almost not affected by the PMI and postmortem storage temperature, but is mainly related to the time of injury. Therefore, a linear regression model can be established to infer the time of injury. [ABSTRACT FROM AUTHOR]

Soybean nutritional quality traits are generally quantitative traits and are regulated by multiple genes. At present, a large number of molecular markers related to quality traits have been located, but there were few available markers verified in soybean breeding populations. In this study, we selected 288 soybean varieties from Huang-Huai-Hai region and 19 wild/semi-wild soybean accessions as a natural population. We analyzed their protein, oil, fatty acid, and isoflavone contents by NIR, GC, and HPLC methods. We selected 18 SSR markers closely linked to quality traits to identify their genotypes by capillary electrophoresis method, and verify the molecular markers associated with nutritional quality traits using association analysis based on the Tassel 2.1 software. The results showed that there were three markers associated with oil content, three markers associated with the content of protein plus oil, one marker associated with palmitic acid, one marker associated with stearic acid, two markers associated with oleic acid, and two markers associated with linolenic acid, and the elite alleles of these loci were also investigated. Our study provided reliable molecular markers for soybean quality molecular breeding. [ABSTRACT FROM AUTHOR]

For the shortage that coal piling sensor based on limit switch cannot monitor fault signal of coal piling in time and accurately because the limit switch is easy to be influenced by external environment such as dust intrusion and humidity leading rust and corrosion, the paper proposed a design scheme of a novel mine-used I.S. sensor of coal piling based on mercury switch. The sensor uses mercury switch to send fault signal to protection and control system of belt conveyor once coal is piled up, so as to prevent continuous coal piling and protect belt conveyor. The practical application showed that the sensor is stable in running and has high reliability.

In order to remove the moisture and upgrade the quality of lignite with efficient methods, a specially-designed microwave equipment was used to remove water from the lignite and the key influencing factors during the process were analyzed. The effects of coal particle sizes, radiation powers and initial moisture contents on the dewatering process were investigated. The results indicate that there were conceptually four stages (preheating stage, pressurizing stage, constant-rate drying stage and falling-rate drying stage) during the whole drying process in microwave. The temperature of lignite rose quickly while the moisture content is nearly constant in preheating stage. The dehydration rate increases notably in the pressurizing stage as the seepage flow generated from the large pressure gradient between internal and external particles. The vapor pressure and dehydration rate is steady in the constant-rate drying stage. The dehydration rate decreases while the lignite temperature increases in the falling-rate drying stage. The peak drying rate could reach 11% per minute when the particle size is 0.6-3.0 mm. The drying rate increases with the increasing microwave output power when the power is less than 600 W. Generally, the high initial moisture content of coal would cause high drying rate, but slow increase in lignite temperature. [ABSTRACT FROM AUTHOR]

Important forensic diagnostic indicators of sudden death in coronary atherosclerotic heart disease, such as acute or chronic myocardial ischemic changes, sometimes make it difficult to locate the ischemic site due to the short death process, the lack of tissue reaction time. In some cases, the deceased died of sudden death on the first-episode, resulting in difficulty for medical examiners to make an accurate diagnosis. However, clinical studies on coronary instability plaque revealed the key role of coronary spasm and thrombosis caused by their lesions in sudden coronary death process. This paper mainly summarizes the pathological characteristics of unstable coronary plaque based on clinical medical research, including plaque rupture, plaque erosion and calcified nodules, as well as the influencing factors leading to plaque instability, and briefly describes the research progress and technique of the atherosclerotic plaques, in order to improve the study on the mechanism of sudden coronary death and improve the accuracy of the forensic diagnosis of sudden coronary death by diagnosing different pathologic states of coronary atherosclerotic plaques.

Objectives: To estimate postmortem interval (PMI) by analyzing the protein changes in skeletal muscle tissues with the protein chip technology combined with multivariate analysis methods., Methods: Rats were sacrificed for cervical dislocation and placed at 16 ℃. Water-soluble proteins in skeletal muscles were extracted at 10 time points (0 d, 1 d, 2 d, 3 d, 4 d, 5 d, 6 d, 7 d, 8 d and 9 d) after death. Protein expression profile data with relative molecular mass of 14 000-230 000 were obtained. Principal component analysis (PCA) and orthogonal partial least squares (OPLS) were used for data analysis. Fisher discriminant model and back propagation (BP) neural network model were constructed to classify and preliminarily estimate the PMI. In addition, the protein expression profiles data of human skeletal muscles at different time points after death were collected, and the relationship between them and PMI was analyzed by heat map and cluster analysis., Results: The protein peak of rat skeletal muscle changed with PMI. The result of PCA combined with OPLS discriminant analysis showed statistical significance in groups with different time points ( P <0.05) except 6 d, 7 d and 8 d after death. By Fisher discriminant analysis, the accuracy of internal cross-validation was 71.4% and the accuracy of external validation was 66.7%. The BP neural network model classification and preliminary estimation results showed the accuracy of internal cross-validation was 98.2%, and the accuracy of external validation was 95.8%. There was a significant difference in protein expression between 4 d and 25 h after death by the cluster analysis of the human skeletal muscle samples., Conclusions: The protein chip technology can quickly, accurately and repeatedly obtain water-soluble protein expression profiles in rats' and human skeletal muscles with the relative molecular mass of 14 000-230 000 at different time points postmortem. The establishment of multiple PMI estimation models based on multivariate analysis can provide a new idea and method for PMI estimation.

Talent is one of the basic and strategic supports for building a modern socialist country in all aspects. Since the 1980s, the establishment of forensic medicine major and the cultivation of innovative talents in forensic medicine have become hot topics in higher education in forensic medicine. Over the past 43 years, the forensic medicine team of Shanxi Medical University has adhered to the joint education of public security and colleges, and made collaborative innovation, forming a training mode of "One Combination, Two Highlights, Three Combinations, Four in One" for innovative talents in forensic medicine. It has carried out "5+3/X" integrated reform, and formed a relatively complete talent training innovation mode and management system in teaching, scientific research, identification, major, discipline, team, platform and cultural construction. It has made a historic contribution to China's higher forensic education, accumulated valuable experience for the construction of first-class major and first-class discipline of forensic medicine, and provided strong support for the construction of the national new forensic talent training system. The popularization of this training mode is conducive to the rapid and sustainable development of forensic science, and provides more excellent forensic talents for national building, regional social development and the discipline construction of forensic science.

Medical disputes are one of the common problems concerned by the whole world. All countries and regions have established their own medical dispute resolution mechanisms, in accordance with their own national conditions. Medical dispute identification opinions, as one of the important bases for identifying the responsibilities of both doctors and patients, play a pivotal role in the process of dispute settlement. A reasonable medical dispute resolution mechanism and standardized medical dispute identification model can help resolve disputes flexibly and reduce the conflict between doctors and patients. This paper briefly compares the medical dispute resolution mechanism and identification mode of China and several other representative countries (the United States, Britain, France, Germany, Italy, Japan, etc.), and discusses their respective characteristics and shortcomings, to bring some enlightenment to the medical dispute resolution and identification in our country.

Objectives: To select four algorithms with relatively balanced complexity and accuracy among deep learning image classification algorithms for automatic diatom recognition, and to explore the most suitable classification algorithm for diatom recognition to provide data reference for automatic diatom testing research in forensic medicine., Methods: The "diatom" and "background" small sample size data set (20 000 images) of digestive fluid smear of corpse lung tissue in water were built to train, validate and test four convolutional neural network (CNN) models, including VGG16, ResNet50, InceptionV3 and Inception-ResNet-V2. The receiver operating characteristic curve (ROC) of subjects and confusion matrixes were drawn, recall rate, precision rate, specificity, accuracy rate and F 1 score were calculated, and the performance of each model was systematically evaluated., Results: The InceptionV3 model achieved much better results than the other three models with a balanced recall rate of 89.80%, a precision rate of 92.58%. The VGG16 and Inception-ResNet-V2 had similar diatom recognition performance. Although the performance of diatom recall and precision detection could not be balanced, the recognition ability was acceptable. ResNet50 had the lowest diatom recognition performance, with a recall rate of 55.35%. In terms of feature extraction, the four models all extracted the features of diatom and background and mainly focused on diatom region as the main identification basis., Conclusions: Including the Inception-dependent model, which has stronger directivity and targeting in feature extraction of diatom. The InceptionV3 achieved the best performance on diatom identification and feature extraction compared to the other three models. The InceptionV3 is more suitable for daily forensic diatom examination.

Diatom test is the main laboratory test method in the diagnosis of drowning in forensic medicine. It plays an important role in differentiating the antemortem drowning from the postmortem drowning and inferring drowning site. Artificial intelligence (AI) automatic diatom test is a technological innovation in forensic drowning diagnosis which is based on morphological characteristics of diatom, the application of AI algorithm to automatic identification and classification of diatom in tissues and organs. This paper discusses the morphological diatom test methods and reviews the research progress of automatic diatom recognition and classification involving AI algorithms. AI deep learning algorithm can assist diatom testing to obtain objective, accurate, and efficient qualitative and quantitative analysis results, which is expected to become a new direction of diatom testing research in the drowning of forensic medicine in the future.

Objective: To investigate the anticancer efficacy and the hepatic and renal toxicity of As2O3-lipiodol emulsion via transarterial embolization in a rabbit VX2 liver tumor model., Methods: VX2 tumors were implanted in rabbit livers successfully, followed by transarterial embolization with high-dose As2O3(5 mg/kg with 0.2 mL lipiodol, n=10), low-dose As2O3(1 mg/kg with 0.2 mL lipiodol, n=10), and control(0.2 mL lipiodol, n=10). The growth ratios and microvessel densities(MVDs) of the tumors were estimated by multi-row spiral CT and CD34 immunohistochemical staining, respectively. Hepatic and renal function was also evaluated by means of blood biochemical analysis., Results: The growth ratios of the tumors differed significantly among three groups(P<0.01). The high-dose and low dose group showed significantly lower tumor growth ratios[44.05%(-36.40%~64.60%), 95.20%(-11.60%~159.40%)] than control group[145.55%(98.90%~250.30%), all P<0.05]. The MVDs of the tumors were significantly lower in the high-dose(21.4±10.6) and low-dose group(34.1±12.0) than those in control group(57.9±16.1,all P<0.05). The levels of blood ALT and AST obtained 28 days after transarterial embolization were significantly lower in the high-dose[(25.50±12.37)U/L,(24.25±10.89)U/L] and low-dose group[(45.00±14.04)U/L,(35.22±11.86)U/L] than in control group[(79.12±30.52)U/L,(75.25±25.89)U/L, all P<0.05]., Conclusion: As2O3-lipiodol emulsion via transarterial embolization has anticancer effect without significant hepatic and renal functional damage in rabbit VX2 liver tumors.

Objective: To explore the influence of signal noise ratio (SNR) on analysis of clear cell renal cell carcinoma (CCRCC) using DWI with multi-b values., Methods: The images of 17 cases with CCRCC were analyzed, including 17 masses and 9 pure cysts. The signal intensity of the cysts and masses was measured separately on DWI for each b value. The minimal SNR, as the threshold, was recorded when the signal curve manifest as the single exponential line. The SNR of the CCRCC was calculated on DWI for each b value, and compared with the threshold by independent Two-sample t Test., Results: The signal decreased on DWI with increased b factors for both pure cysts and CCRCC. The threshold is 1.29 ± 0.17, and the signal intensity of the cysts on DWI with multi-b values shown as a single exponential line when b ≤ 800 s/mm(2). For the CCRCC, the SNR is similar to the threshold when b = 1 000 s/mm(2) (t = 0.40, P = 0.69), and is lower when b = 1 200 s/mm(2) (t = -2.38, P = 0.03)., Conclusion: The SNR should be sufficient for quantitative analysis of DWI, and the maximal b value is 1000 s/mm(2) for CCRCC.

Objective: To evaluate the clinical value of PVE (portal vein embolism) prior to surgery in primary liver cancer (PLC) patients and the effect of liver cirrhosis on liver lobe hyperplasia after PVE., Methods: 13 patients with primary liver cancer non-suitable for curative hepatectomy underwent k sequential transcatheter arterial chemoembolization (TACE) (1-3 times) and percutaneous selective portal vein embolization (PVE) when the remnant liver volumes were predicted to be insufficient. All patients were divided into non-cirrhosis (n = 7) and cirrhosis group (n = 6). Left liver remnant volumes were assessed by computed tomography (CT) before and after PVE. Right liver resection was performed when the remnant liver volume was sufficient., Results: All patients underwent TACE treatment was successful. The frequency of TACE was 1-3. PVE was all successfully performed at weeks 2-4 after final TACE, all PVE patients subsequently underwent hepatic lobectomy. Left liver volume increased from (457.0 ± 121.0) cm(3) pre-PVE to (633.6 ± 120.2)cm(3) post-PVE. Hepatic lobe volume increased (44.4 ± 39.7)%. Statistical difference existed in left hepatic lobe volume before and weeks 4-6 after PVE (P = 0.000). The mean volume of left liver, calculated before and 4-6 weeks after PVE, increased from (442.0 ± 96.8) to (652.3 ± 115.8) cm(3) in non-cirrhotic group and from (474.5 ± 152.4) to (611.7 ± 132.3) cm(3) in cirrhotic group. Hepatic lobe volume increased (54.5 ± 50.7)% and (32.7 ± 19.9)% respectively. Statistical differences were both detected in left hepatic lobe volume before and 4-6 weeks after PVE (P = 0.011, P = 0.003). However, no significant inter-group difference existed at Weeks 4-6 weeks (P = 0.295) . Liver function damage was minimal after PVE and no serious complications occurred., Conclusion: Sequential transcatheter arterial chemoembolization, TACE and percutaneous selective PVE before surgery may cause remnant liver compensatory hypertrophy and increase the resection rate of primary liver cancer. Liver cirrhosis has no significant effect on liver lobe hyperplasia after PVE.

Objective: To explore the value of on-pump beating-heart coronary artery bypass grafting (OnP-BH CABG) for left-main patients with coronary heart disease through a comparative study with conventional coronary artery bypass grafting (CCABG)., Methods: The clinical data were retrospectively analyzed for 66 patients of OnP-BH and 48 control cases undergoing CCABG from January 2009 to January 2012 at Department of Cardiac Surgery, People's Hospital of Zhengzhou University., Results: OnP-BH group had a better clinical outcome than CCABG group. There were obvious statistical difference in cardiopulmonary bypass (CPB) time, mean ventilation time, intensive care unit stay and recovery time of plasma cardiac troponin I (OnP-BH group vs CCABG group:(89 ± 25) vs (117 ± 28) min, (15 ± 14) vs (27 ± 19) h, (57 ± 27) vs (79 ± 34) h, (6.2 ± 1.8) vs (7.0 ± 2.4) d, all P < 0.05). The data of preoperative cTnI showed no significant difference between two groups (P > 0.05) .However, after CPB, significant intergroup difference existed in the level of cTnI (µg/L) OnP-BH group vs CCABG group: (0.5 h after CPB: (0.132 ± 0.022) vs (0.265 ± 0.014) , 1 h after CPB: (0.341 ± 0.027) vs (0.572 ± 0.046) , 1 h after operation: (0.641 ± 0.036) vs (0.932 ± 0.047) , 6 h after operation: (1.212 ± 0.765) vs (1.627 ± 0.542) and 24 h after operation: (1.496 ± 0.263) vs (1.734 ± 0.328) , all P < 0.05)., Conclusions: On-pump beating-heart coronary artery bypass grafting is a feasible surgical approach for left-main patients. And it has a low risk and causes less myocardial damage.

Objective: In order to explore the regulating effects of Egr-1 promoter sequences in transcriptional targeting by 5-fluorouracil (5-Fu) on the expression of hematopoietic growth factor genes., Methods: The human GM-CSF cDNA and enhanced green fluorescent protein (EGFP) cDNA were linked together with IRES and then inserted into the expression vector pCIneo under control of the Egr-1 promoter (Egr-EG). The vector was transferred into human bone marrow stromal cell line HFCL by lipofectin(TM). The transfected cell clones (HFCL/EG) have been selected by the addition of G418. The cells are exposed to the clinically important anticancer agent 5-fluorouracil. The activity of EGFP in HFCL/EG cells was detected by flow cytometry. The post-chemotherapeutical expression of GM-CSF in HFCL/EG was confirmed with ELISA and Western blot and RT-PCR respectively. The effect of N-acetylcysteine (a free radical scavenger) on GM-CSF production post-exposure to 5-Fu was examined. The HFCL/EG cells were transplanted intravenously into B16 melanoma in C. B-17 combined immunodeficient (SCID) mice. 5-Fu was given i.p. at Day 3. The white blood cell number in peripheral blood, the expression of EGFP and GM-CSF and in human stromal cell engrafted in recipient mice were detected by flow cytometry and RT-PCR respectively. Tumor volume in tumor-bearing mice was calculated., Results: The results indicated that the activity of EGFP and the amounts of secreted GM-CSF in HFCL/EG cells exposed to 5-Fu increased as compared to non-5-Fu group with flow cytometry, RT-PCR and ELISA respectively. N-acetylcysteine significantly decreased the concentration of GM-CSF in HFCL/EG cells treated with 5-FU. In contrast to two control groups, HFCL/EG (Egr-1 regulatory element-derived expression of GM-CSF gene therapy) resulted in a proportionally obvious increase in the number of white blood cell after chemotherapy and no significant difference was found for tumor inhibition in recipient mice., Conclusions: These in vitro data provide an experimental basis for use of gene therapy of hematopoietic growth factor gene regulated by Egr-1 promoter to protect hematopoiesis from 5-Fu-injury effects.

Objective: To evaluate the efficacy of in vivo magnetic resonance imaging (MRI) of mesenchymal stem cells (MSCs) injected intravascularly in treatment of acute renal failure (ARF) , and to investigate the changes of renal function and pathology of ARF after MSC transplantation., Methods: Rat MSCs were isolated and labeled with Fe2O3-PLL in vitro. Thirty SD rats underwent intramuscular injection of glycerol so as to establish ARF models and then randomly divided into 3 equal groups: Group I undergoing injection of labeled MSCs into abdominal aorta via transcatheter, Group II injected with unlabelled MSCs, and Group III injected with normal saline as controls. MRI of kidney was conducted before injection, and 0.5 h, and 1, 2, and 5 days after injection. One and 2 days after the transplantation 3 rats from each group underwent MRI and extraction of blood samples from the abdominal aorta and then killed with their kidneys taken out, and 5 days after the rest rats were all killed after MRI with their kidneys taken out. Serum creatinine (Scr) and blood urea nitrogen (BUN) were examined so as to evaluate the renal function. Microscopy was conducted to observe the pathological changes. Prussian blue + CD68 antibody staining was performed to identify the labeled MSCs., Results: MRI showed decrease of signal intensity in renal cortex on the T2 *-weighted MR images up to 5 days after transplantation. Histological analysis showed that most Prussian blue-positive cells were in the glomerular capillaries, corresponding to the areas where signal intensity decrease was observed by MRI. The Scr and BUN levels 2 and 5 days after the implantation of Group I were both lower than those of the control group, and there were not significant differences in the Scr and BUN levels between Groups I and II. Renal tubular injury scoring showed that the renal tubular injury was significantly lighter than that of the control group., Conclusion: 1.5-T MRI seems a good in vivo technique to monitor the magnetically labeled MSCs administered into the abdominal aorta of ARF animals, which are distributed in the glomerular capillaries in the early stage after transplantation. MSCs may promote the recovery of ARF.

Objective: Accumulating evidence suggests that the endothelial progenitor cells (EPCs) can reendothelialization the injured endothelium. Superparamagnetic iron-oxide particles are being used for intracellular magnetic labeling of cells and in vivo cells tracking. The aim of this study was to investigate the possibility of depict and track magnetically labeled EPCs in vivo for carotid artery endothelium injured New Zealand White rabbit model by 1.5 T magnetic resonance imaging system after EPCs transplantation., Methods: The EPCs of New Zealand White rabbit were isolated, confirmed, expanded and then incubated with home synthesized Fe2O3-PLL for 24 hours, Prussian blue stain was performed for showing intracellular irons. The model of carotid arterial injury was performed by 2.5 F balloons. The group A of 5 rabbits were transplanted with magnetically labeled EPCs, the group B of 5 rabbits were received fluorescent-labeled EPCs, and 5 rabbits of the group C were received the same volume of saline injection immediately after the carotid artery endothelium was injured. The transfused EPCs were strictly restricted to the injury site. MR imaging and histology were performed and compared 7 days late., Results: The Epcs labeling efficiency of Fe2O3-PLL was more than 95% identified by Prussian blue stain. Seven days after the transplanted of EPCs, only in group A, the injured endothelium of carotid artery wall had the signal intensity loss in T(2)WI MRI, which corresponding to the injured endothelium where the most Prussian blue staining-positive cells were in histopathological analyses. While histopathological slides showed that the fluorescence-positive cells in the injured endothelium which had been transplanted Dil labeled EPCs also. The group C was either in negative., Conclusion: The rabbits endothelial progenitor cells can be effectively labeled with Fe2O3-PLL, 1.5 T magnetic resonance imaging system could depict and monitor the magnetically labeled endothelial progenitor cells homing to the injured endothelium of the artery, which may have much more potential values for studying the engraftment of EPCs in cardiovascular disease.

Objective: To observe whether bone mesenchymal stem cells (MSCs) have the potential to transdifferentiate into functional hepatocyte-like cells in the special "niche" as well as the therapeutic feasibility to repair damaged liver in mice., Methods: 20 nude mice were randomly divided into four groups (n = 5 in each group): Group A: 1.0 ml/kg of carbon tetrachloride (CCl(4)) (dissolved in olive oil by ratio of 1:1) was injected into the peritoneum of mice twice a week for 5 weeks. GFP-positive MSCs (1 x 10(6) cells) were injected into the caudal tail vein 1 week after the first dose of CCl(4); Group B: treated with CCl(4) as in A, but received the same volume of saline; Group C: normal nude mice with GFP-positive MSCs Transplanted in the same way as in A. Group D: normal controls. 4 weeks after the cell transplantation, all animal subjects were killed. Liver function tests (LFT), histology of HE and Masson staining as well as double immunofluorescent staining for GFP and albumin were studied in all groups., Results: The hepatic fibrosis in group A & B confirmed the success of model for liver damage and there was no marked difference in the percent of the area occupied by collagen between two groups (10.5 +/- 1.5 vs 12.7 +/- 1.6, t = -2.238, P > 0.05). GFP-positive MSCs were mainly observed around portal area or interspace of lobules in group A. Some of GFP-positive cells also express albumin (35% +/- 7%). While in group B, C or D, there is no such findings. The level of serum albumin in group A was higher than that in group B (24.4 g/L +/- 3.3 g/L vs 18.6 g/L +/- 2.9 g/L, P < 0.05) while the level of ALT was also different between two groups (121 U/L +/- 21 U/L vs 192 U/L +/- 29 U/L, P < 0.05)., Conclusion: The stimulus of persistent liver damage might enhances the migration of MSCs to the liver, in which some of the MSCs have the potential to transdifferentiate into hepatocyte-like cells. Transplantation of MSCs might amend the damaged tissue of host liver to a certain extent.

Objective: To investigate the inhibitory effect of antisense oligodeoxynucleotides targeting HER-2 mRNA on growth of breast cancer., Methods: Human breast cancer cells of the line SK-BR-3 that overexpresses HER-2 were injected subcutaneously into BALB/c nude mice. Seven to ten days after tumors were collected and made into homogenate. Antisense oligodeoxynucleotide HA6722 targeting HER-2 mRNA and its control sequence Scramble were synthesized. Forty-nine BALB/c nude mice were injected with homogenate of SK-BR-3 cells and then randomly divided into 7 equal groups: Group 1, injected intravenously with docetaxel (TXT) 7.5 mg.kg(-1).d(-1) once a week twice; Group 2, injected intravenously with TXT 15 mg.kg(-1).d(-1) once a week twice; Group 3, injected intravenously with TXT 7.5 mg.kg(-1).d(-1) once a week twice + HA6722 5 mg.kg(-1).d(-1) for 12 days; Group 4, injected intravenously with HA6722 5 mg.kg(-1).d(-1) for 12 days; Group 5, injected intravenously with TXT 7.5 mg.kg(-1).d(-1) once a week twice + Scramble6722 5 mg.kg(-1).d(-1) for 12 days; and Group 7, injected with normal saline. After the drug administration the mice were observed for additional 3-4 weeks to measure the size of tumor every other day. Then the mice were killed and the tumors were taken out to be examined. The inhibition rate was calculated., Results: The inhibition rate of tumor in Group 3 was 88.3%, not significantly different from that in Group 2 (88.7%, P > 0.05). The inhibition rate in Group 4 was 76.3%. The inhibition rates of tumor of Groups 2, 3, and 4 were all significantly higher than that in Group 7. However, the inhibition rate of tumor of Group 6 was not significantly different from that in Group 7., Conclusion: Antisense oligodeoxynucleotides targeting HER-2 mRNA inhibits the growth of breast cancer in a sequence specific and dose-dependent manner.