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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.

Tea (Camellia sinensis L.) is one of the most important and traditional economic crops widely cultivated in the subtropical regions of China, which are usually developed from forestland. Soil enzyme activity is an important indicator of soil fertility and nutrient transformation. The purpose of this study is to investigate the seasonal dynamic characteristics of soil properties and enzyme activities of different planting patterns in Wuyishan city, and to provide theoretical basis for reasonable evaluation of soil ecological effects of organic tea cultivation. In this paper, three different planting patterns (forestland, conventional and organic tea gardens) were selected as the research objects. Soil samples were collected in May, August, November and February from 2021 to 2022. The soil properties and enzyme activities (urease, nitrate reductase, polyphenol oxidase, catalase, invertase and acid phosphatase) were determined in different seasons, and the dynamic changes with seasons were also investigated. The results show that: comparing with the forestland, the contents of soil ammonium nitrogen, total phosphorus, available phosphorus and available potassium increased significantly in the conventional tea garden, while the total potassium and pH decreased significantly. Compared with the conventional tea garden, the soil organic matter and total nitrogen contents increased significantly in the organic tea garden. The soil total phosphorus, available phosphorus, total potassium and available potassium contents decreased significantly. The soil pH also increased, and the proportion of soil nutrients was more coordinated. The effects of planting pattern and season and their interactions on urease and peroxidase activities were significant. Compared with the forestland, the soil urease, polyphenol oxidase, catalase and acid phosphatase activities decreased by 12.05% to 63.55% in the conventional tea garden, while urease activities significantly increased by 324.95% in the organic tea garden, and the soil nitrate reductase activities were not changed by planting mode. In general, the soil urease, polyphenol oxidase, invertase and acid phosphatase activities were significantly higher in summer and autumn (May and August) than those in winter and spring (November and February). The highest soil nitrate reductase and catalase activities were found in spring (February). The results of permutational multivariate analysis of variance show that the effect of planting pattern on the overall soil physical and chemical properties was much greater than that of seasonal changes. Redundancy analysis shows that soil environmental factors explained 77.03% of the variation in soil enzyme activity, and the soil organic matter, total nitrogen, ammonium nitrogen, total phosphorus, soil available phosphorus, total potassium, available potassium and pH were the main driving factors of soil enzymes. In summary, the conversion of forestland into tea gardens has a significant impact on soil properties and enzyme activities. Conventional planting leads to the accumulation of available phosphorus and potassium in tea garden soil and the decrease of soil enzyme activity, while organic planting improves soil enzyme activity and enhances soil carbon and nitrogen nutrient supply capacity, and thus is beneficial for maintaining a sustainable ecosystem in tea garden soil. [ABSTRACT FROM AUTHOR]

In order to develop the best formula for shrimp slide with Hypsizygus marmoreus, according to the main raw materials of shrimp slide with Hypsizygus marmoreus, the colour difference, texture, and sensory scores were used as the quality indicators. Then, the effects of different granularities, different additions of Hypsizygus marmoreus, starch, and egg white on the gelatin of minced shrimp with Hypsizygus marmoreus and shrimp slide were explored, in order to produce the high-quality shrimp slide with Hypsizygus marmoreus. The results showed that Hypsizygus marmoreus of homogenate particles and shrimp slide could be better fused, resulting in the higher whiteness of shrimp slide. Additionally, the maximum values for the gel of minced shrimp and the a* value, gel strength, and rupture force of shrimp slide were achieved with the addition of 7% Hypsizygus marmoreus. The maximum whiteness of shrimp slide was achieved with the addition of 5% starch, but when the amount of starch added was too much, the shrimp slide had obvious powder feeling, and the sensory score decreased sharply. On the other hand, the addition of 3% egg white resulted in the maximum whiteness, a* and gel strength of shrimp slide. An orthogonal test was used to optimize the best formulation of shrimp slide with Hypsizygus marmoreus, resulting in 7% homogenate of Hypsizygus marmoreus, 7.5% starch, and 3% egg white. According to the analysis of nutritional components, the contents of reducing sugar, dietary fibre, and sodium in shrimp slide with Hypsizygus marmoreus were significantly improved (P<0.05)under this formula compared with the shrimp slide without the addition of Hypsizygus marmoreus. [ABSTRACT FROM AUTHOR]

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.

The sapphire single crystal plate with size of 485 mm x 985 mm x 12 mm was successfully prepared by a large-size edgedefined film-fed growth (EFG) furnace designed and developed independently. After cutting and grounding, the crystal was formed into transparent armors composited with glass and polycarbonate. The surface density with the size of 352 mm x 351 mm x 33 mm is 79. 27 kg/m², and the surface density of the other is 79.38 kg/m² with the size of 351 mm x 342 mm x 33 mm. Targeting tests were conducted on the transparent armors using incendiary shells with diameters of 7.62 mm and 12.7 mm, respectively. The experimental results show that the transparent armor based on sapphire crystal plate has excellent impact resistance during firing at a normal angle of 0° and with a distance of 100 m which from target to the armors. [ABSTRACT FROM AUTHOR]

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 order to establish an accurate and feasible concrete adiabatic temperature rise model, based on the exponential model, hyperbolic model and composite exponential model, the exponential model and hyperbolic model were modified by fitting function regression method, and the degree of conformity between the calculated value of the adiabatic temperature rise of the modified model and the measured value was analyzed. Finally, the accuracy and feasibility of using the regression curve method of the fitting function to modify the model were evaluated. The research results show that there is a certain deviation between the calculated value of adiabatic temperature rise directly using exponential model and hyperbolic model, and the degree of deviation is more obvious with the increase of concrete strength grade. The composite exponential model is used as the correction formula of the exponential model, and its calculated adiabatic temperature rise agrees well with the measured value. The modified hyperbolic model is in good agreement with the actual adiabatic temperature rise, and the overall agreement is better than the composite exponential model. However, the modified exponential model still deviates greatly from the actual situation, and the modified method is not applicable to the exponential model. [ABSTRACT FROM AUTHOR]

This paper aims to solve the rent-seeking phenomenon in the process of green building promotion and improve the quality of green buildings. From the perspectives of government regulatory departments, third-party testing agencies, and green building developers, a green building quality supervision game model is constructed. The interactions among various parameters on the quality of green buildings is analyzed. Then, the model is further optimized with a dynamic reward and punishment mechanism. The results show that (1) the supervision of developers is the key to the quality supervision of green buildings. (2) Incremental costs and incremental risks were negatively correlated with green building quality. However, incremental benefits, rent-seeking costs, government rewards, and penalties were positively correlated with green building quality. (3) The dynamic reward and punishment mechanism may contribute to the improvement of green building quality. Finally, a number of policy recommendations were made to improve the quality of green buildings. [ABSTRACT FROM AUTHOR]

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]

Vapor equilibrium transport method is used to prepare near stoichiometric lithium tantalate crystals with high quality. However, it is difficult to prepare large-thickness crystals by this method due to its low solid diffusion rate. In this paper, based on the diffusion mechanism of lithium tantalate crystal, the diffusion of lithium tantalate crystal was carried out by asymmetric diffusion process with lithium rich atmosphere on one side of the wafer and congruent composition atmosphere on the other side. The composition and domain inversion field were characterized. The results show that the asymmetric diffusion technique provides a channel for the diffusion of anti-tantalum ion and increases the diffusion rate of anti-tantalum ion and lithium ion in the crystal, which is beneficial to the preparation of large-thickness near stoichiometric lithium tantalate crystal. [ABSTRACT FROM AUTHOR]

In recent years, radar target recognition based on deep learning has received great attention. However, there are time constraints and resource constraints in actual combat, and the problem of small sample recognition greatly iimits its pefformance in actual recognition tasks. To solve this problem, based on the meta learning algorithm, this paper improves the performance of new tasks by learning meta knowledge from multiple related tasks, introduces the idea of tranffer learning, proposes an improved small sample learning method, and analyzes the application boundary conditions of the method through detalled performance comparison experiments. The experimental resuits based on the measured high resolution range proille data show that the pefformance advantage of meta learning method is outstanding only when there are many target categories in the historical accumulated samples and in the case of minimal samples with high correlation with the target task, the proposed method can significantly improve its comprehensive recognition performance. [ABSTRACT FROM AUTHOR]

High protein content easily leads to nutrient imbalance in feed, reduces the efficiency of digestion and utilization of nutrients in fish, and increases the discharge of pollutants in aquaculture. It not only increases feed cost, but also easily causes water environment pollution. Reducing feed protein level can effectively reduce ammonia nitrogen emission in animal feces, but it may lead to the degradation of animal production performance. Supplementation of restricted amino acids can improve the protein utilization rate of animals and also reduce the nitrogen emission in the breeding process. Yellow catfish (Pelteobagrus fulvidraco) is a benthic small economic fish with a large aquaculture yield. This experiment with yellow catfish hybrid larvae as the research object, explore the supplemental methionine and lysine of low protein feed for yellow catfish hybrid larvae growth performance, body composition, transaminase activity and the influence of antioxidant capacity, to cross the yellow catfish hybrid nutrition requirements and related research, and health breeding to provide theoretical basis and reference. In this study, five experimental diets were formulated and there were three protein levels as 42% (control), 37% (LP1) and 32% (LP2). By using the control diet as standard, other two low-protein diets (37% and 32%) and supplementation with lysine and methionine (LP1+AA and LP2+AA) were formulated. Each diet was fed to triplicate groups of fish for 8 weeks, and the initial weight of fish was (0.96±0.01) g. At the end of the experiment, the growth performance, body composition, transaminase activity and antioxidant capacity of yellow catfish hybrid were measured. The results showed that compared with the control group, (1) the weight gain rate and specific growth rate of yellow catfish hybrid in LP1 group and LP2 group reduced significantly (P<0.05). There was no significant difference in weight gain rate and specific growth rate between LP1+AA and LP2+AA yellow catfish hybrid (P>0.05). (2) The relative expression levels of GH, IGF-1 in pituitary and GH in hypothalamus of yellow catfish hybrid in LP2 group and LP2+AA group decreased significantly (P<0.05), and there was no significant difference between the other groups with control group (P>0.05). (3) There was no significant difference in water content, crude protein, crude fat and crude ash content between muscle and whole fish in each experimental group (P>0.05). (4) There was no significant difference in AST activity in liver and serum among all the groups (P>0.05), and serum ALT activity in LP2 group was significantly higher than that in the control group and LP1+AA group (P<0.05). (5) CAT activity in serum, T-AOC, Cu/Zn-SOD, Mn-SOD and CAT mRNA relative expression in liver of both LP2 and LP2+AA groups decreased, and ROS content in liver and serum increased. There were no significant differences in SOD, CAT, T-AOC, MDA and ROS in liver and serum and Cu/Zn-SOD, Mn-SOD and CAT mRNA relative expression in liver of LP1+AA groups (P>0.05). These results showed that reducing the protein content of both 5% and 10% in the feed would negatively affect the growth performance and antioxidant capacity of yellow catfish hybrid. Reducing the protein content of the feed by 5% and adding lysine and methionine would not significantly affect the growth performance and antioxidant capacity of yellow catfish hybrid. Therefore, we suggest that the protein content in feed can be reduced by supplementing amino acid in feed production. [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.

Aiming at the problem of radar small shot target recognition, a comprehensive solution is proposed by combining meta learning and transfer learning, to provide appropriate model learning and classification methods according to different practical application scenarios, so as to improve the efficiency and accuracy of radar small shot target recognition. At the same time, through several groups of comparative experiments, the model performance changes of few shot learning algorithm in the actual radar target recognition scene are deeply analyzed, and two important conclusions that can effectively guide the engineering application are obtained. One is the performance of meta learning model is good when the source task information is sufficient and the difference between the source task and the target task is small, otherwise the transfer learning method is more suitable. The other one is the few shot learning model pay different attention to the external features of radar targets, so the recognition oriented radar imaging should focus on the salient features of the model requirements. [ABSTRACT FROM AUTHOR]

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To investigate the trade-off between the twig size and leaf size, we measured the total leaf mass, stem mass, individual leaf mass and leafing intensity of typical bamboo' s ( Phyllostachys edulis, Indocalamus tessellatus, Oligostachyum oedogonatume, Yushania hirticaulis and Yushania wuyishanensis) twigs at different altitudes in Wuyi Mountain. The results showed that the exponents of the scaling between total leaf mass and stem mass on twigs significantly decreased with increasing altitude for all the five bamboo species. The common scaling exponents of total leaf mass vs. stem mass for P. edulis, I. tessellatus and O. oedogonatum were 0.9, 0.85 and 0.8, respectively. A common slope of 0.79 was observed in total leaf mass vs. stem mass in Y. hirticaulis and Y. wuyis-hanensis. There was significant negative correlation between individual leaf mass and leafing intensity among bamboo species, except Y. wuyishanensis. A common slope of - 1.12 existed between individual leaf mass and leafing intensity for five bamboo species. In conclusion, bamboos at low altitudes tended to support more leaf biomass while preferring to invest more to stem biomass at high altitudes. Although the stem mass investment of different bamboo' s twig increased with altitude, the leafing intensity strategies based on stem mass were determined by the leaf size construction rather than altitude. [ABSTRACT FROM AUTHOR]

To explore the consumption of energy sources and swimming performance of juvenile Gambusia affinis and Tanichthys albonubes after starvation, contents of glycogen, lipid and protein, burst swimming speeds (Uburst), and critical swimming speeds (Ucrit) at different starvation times (0, 10, 20, 30 and 40 days) were evaluated. The results showed that, at 0 day, contents of glycogen and lipid were significantly lower in G. affinis than those in T. albonubes, whereas no significant difference in content of protein between two experimental fish was found. Swimming speeds in G. affinis were significantly lower than those in T. albonubes for all swimming performances. After different starvation scenarios, content of glycogen both in G. affinis and T. albonubes decreased significantly in power function trend with starvation time and were close to zero after starvation for 10 days, whereas the contents of lipid and protein were linearly significantly decreased. The slope of line regression equation between content of lipid and starvation time in G. affinis was significantly lower than that in T. albonubes, whereas there was a significantly higher slope of line equation between content of protein and starvation time in G. affinis. 40 days later, the consumption rate of glycogen both in G. affinis and T. albonubes were significantly higher than that of lipid, while the consumption rate of protein was the least. Consumption amounts of glycogen in all experimental fish were the least, G. affinis consumed more protein than lipid, and T. albonubes consumed more lipid than protein. Uburst and Ucrit decreased significantly linearly with starvation time for all experimental fish. Slope of linear equation between Uburst and starvation time was not significantly different between G. affinis and T. albonubes. However, the straight slope between Ucrit and starvation time was significantly lower in G. affinis than that in T. albonubes. These findings indicated that there was close relationship between the consumption of energy sources and swimming performance in starvation. Although the store amounts of energy sources and swimming performance were lower in G. affinis than those in T. albonubes, G. affinis mainly used protein during starvation. The result of more stable lipid content and Ucrit in G. affinis in starvation compared with that in T. albonubes indicated that G. affinis had a fair endurance to starvation, which helped them to adapt to the poor nutrition environment in stream habitat. [ABSTRACT FROM AUTHOR]

In order to solve the problems such as the low degree of automation of concrete curing room temperature control, the difficulty for the temperature control to meet the requirements of national standard, the parameter self-tuning fuzzy PID control algorithm was put forward. The algorithm through the real-time correction PID parameters to ensure the system accuracy and stability. The Matlab simulation results showed that the parameter self-tuning fuzzy PID control system has better stability and robustness than the traditional PID. [ABSTRACT FROM AUTHOR]

For the low accuracy rate of the primary user detection in the wireless channel environment, this paper proposes a method based on cyclostationary principal component analysis(PCA) and relevant vector machine(RVM) for spectrum sensing under the low signal to noise ratio( SNR) environment in cognitive radio. This method combines PCA with the RVM classification algorithm to solve spectrum sensing problem in cognitive network. A set of cyclic spectrum features are first calculated, and the PCA is applied to extract the most discriminate feature vector as training samples and testing samples for classification. The RVM is trained by training samples. Finally, the trained RVM is utilized to detect and decide the existence of the primary user. It is observed that the maximum increase of the detection probability of the proposed algorithm can be increased about 61. 6% in comparison with artificial neural network(ANN), support vector machine(SVM) and maximum-minimum eigenvalue (MME). Simulation results show the proposed algorithm can effectively detect primary user signals. [ABSTRACT FROM AUTHOR]

In this study, we developed a fast and non-destructive technology for the prediction of the nitrogen content in lettuce leaves based on hyperspectral imaging technology which contains abundant spectral and spatial information in an object. First, hyperspectral images of lettuce leaves in the visible and near infrared (390-1050 nm) regions were acquired by the hyperspectral imaging system, and then the corresponding nitrogen content in the lettuce leaves were obtained by Kjeldahl method successively. The binary mask image was successfully determined by the method of dividing the image of very high reflectance intensity by the image of very low reflectance intensity with a certain threshold, and ROI (Region of Interest) in the sample of lettuce leaf was determined by removing the regions of noise using the acquired binary mask image. As the hyperspectral imaging technology provided much more information including spectral and spatial information for all the samples of lettuce leaves, and in which some information is noisy and redundant. In fact, this leads to the difficulty of meeting the needs for fast and efficient detection of some objects. So it is very hard to be directly used for on-line industrial application in our daily life. Therefore, effective selection of several characteristic wavelengths is necessary for the hyperspectral images. In this paper, the initial investigation was carried out by using a principal component analysis (PCA) to identify a number of potential characteristic wavelengths (662.9 nm, 711.7 nm, 735.0 nm, 934.6 nm) according to the weight coefficient distribution curve of the first three principal component images (PC1, PC2, PC3) under the full wavelengths. Both spectral data and texture data based on a co-occurrence matrix were extracted from the four characteristic wavelength images on the ROI, and the texture data of the first three principal component images were also extracted simultaneously. Then spectral data from four characteristic wavelength images, texture data (from four characteristic wavelength images, from the first three principle component images) and the combined data were utilized to develop different SVR (support vector machine regression) models to predict the nitrogen content in the lettuce leaves respectively. According to the performance of all the SVR models in the calibration set and the prediction set, the experiment results show that, from the calibration performance index, the model based on spectral data combined texture data from four characteristic wavelength images is the best with a coefficient of determination (R2C =0.996) and the root-mean-square error (RMSEC) of 0.034. From the prediction performance index, however the model based merely on spectral data is the best with a coefficient of determination (R2p=0.86) and the root-mean-square error (RMSEP) of 0.22. This study provides valuable information for rapid and non-destructive nitrogen detection in crops. [ABSTRACT FROM AUTHOR]

Combined with the vocational education and practical teaching characteristics, through the analysis of the importance of practical teaching and the existing problems, we analyze from the aspects of the top-level design, teaching methods, examination method reform, so as to provide policy reference for practical teaching of computer courses. [ABSTRACT FROM AUTHOR]

The article focuses on the study which investigates the efficacy of valproic acid (VPA) on the developmental competence of porcine handmade cloning (HMC) reconstructed embryos from different donor cells. The study used histone deacetylase inhibitors VPA. The results of the study showed that the blastocyst formation rate was 48. 92% and the total blastosphere cellular rate was 80. 33.

Population characteristics deserve closer study when two kinds of conflict information spread over social network at the same time. According to complexity theory and sociology achievement, we developed conflict information spreading model by using SIR model on network. Here we introduced three manners for individual to resolve conflict information involving "first impressions are strongest", "herd effect" and "leader opinion" into the spreading process, and then conducted contrastive experiments of the model corresponding different behaviors on the large-scale social network. The experiment results show that social network structure and individual manners significantly affect the information spreading. From local interactions to collective behavior, global feature has more diverse trends than local feature, and this study will contribute to the explanation of large-scale population characteristics such as go to extremes and diversification. [ABSTRACT FROM AUTHOR]

Seed protein content, controlled by quantitative genes, is a very important trait for soybean. To idenlify the soybean quantitative trait loci (QTL) of seed protein content, which provides a base for MAS breeding and elite genes - discovering, a cross was made between the elite cultivar Zhonghuang 13, which exhibits a comprehensive excellent performance and has the higher protein content and the variety Dongshan 69 which has the lower protein content. The BC2F2 and BC2F3 backcross populations were further developed to identify protein composite interval mapping (ICIM), two QTLs flanked by the marker interval Satt396 to Satt180 and Sct_001 to Satt654 were both detecled in the BC2F2 and BC2F3 families. In the BC2F2 families, 3 QTLs were found on A1, C1 and J linkage groups, which accounted for 10.00%, 7.07% and 9.23% phenotypic variance, respectively. In the BC2F3 families, 4 QTLs were identified on B1, C1, I and J linkage groups, which explained 17. 57%, 3. 46%, 8. 53% and 11. 80% phenotypic variance, respectively. Region Sct_001 to Satt654 may be a new interval associated wilh protein content QTL. [ABSTRACT FROM AUTHOR]