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ObjectiveTo establish the structural confirmation methods of three suspected new psychoactive substances （NPSs）, and explore a more general qualitative testing method.MethodsInfrared absorption spectroscopy （IR）, gas chromatography-mass spectrometry （GC-MS）, 1H-nuclear magnetic resonance spectroscopy （1H-NMR）, 13C-nuclear magnetic resonance spectroscopy （13C-NMR）, 19F-nuclear magnetic resonance spectroscopy （19F-NMR） and other techniques were used to identify the composition and structure of 5 samples containing suspected NPS submitted by public security bureaus.ResultsNPSs were found in the above 5 samples, and 3 were confirmed as NPS included in the newly listed controlled substances on July 1, 2024, namely 2-（methylamino）-2-（2-methylphenyl）cyclohexan-1-one （2-MDCK）, 2-（ethylamino）-2-（2-fluorophenyl）cyclohexan-l-one （2-FXE）, 1-（3,4-methylenedioxyphenyl）-2-（dimethylamino）pentan-1-one （dipentylone）, respectively. The first two substances were phencyclidine NPS, and the third substance was synthetic cathinone NPS.ConclusionThis study systematically summarizes the distinguishing features of the infrared absorption spectrometry, nuclear magnetic resonance spectroscopy and mass spectrometry of three NPSs, which can provide a reference for the qualitative identification of unknown substances.

In the era of globalized geo-economics, international big channel are changing the way geo-economic elements flow across borders, expanding cooperation spaces such as ports and border-free trade zones to more distant inland areas and shaping new ways of cross-border geo-economic cooperation. As an international land and sea channel connecting China and Myanmar, the China-Myanmar Indian Ocean New Channel (hereinafter "the Channel") is of great importance for promoting geo-economic cooperation between the two countries and the construction of the Belt and Road Initiative. However, owing to various obstacles in geo-economic cooperation, the geo-economic effect of the Channel has not been effectively brought into play. In this study, the obstacles to geo-economic cooperation in the Channel and its collaborative mechanisms were analyzed to provide important scientific and technological support for enhancing its geo-economic effects and strengthening geo-economic cooperation between China and Myanmar. The natural geography of the region with its high mountains and deep valleys and the frequently occurring natural disasters are natural obstacles that limit the geo-economic effect of the Channel. Moreover, the difference in economic development between China and Myanmar is not conducive to the deepening of geo-economic cooperation in the Channel. Complex armed conflicts have disrupted the construction of the Channel and China's investment in its route, and the potential intervention of India and the United States will become an added constraint on its further development. Furthermore, the multiple stakeholders game in the construction of the Channel may bring geo-risks. Contrary to preconceived notions, geo-economic cooperation in the Channel is not a strategy for regional control, but rather to create an international trade corridor deeply related to transportation logistics, supply chains, industrial chains and value chains. To promote geo-economic cooperation in the Channel, its construction should be based on a multi-level collaborative mechanism for geo-economic cooperation. At the national level, the docking of development strategies between China and Myanmar should be strengthened by promoting integration of the Channel into the Belt and Road Initiative, strengthening the docking of China-Myanmar policy communication mechanisms, and formulating a long-term development strategy plan for the Channel. At the channel level, the geo-economic effect of the Channel should be upgraded by promoting the linkage of internal and external infrastructures, strengthening geo-economic element cross-border flow and industrial cooperation, and deepening economic and trade cooperation with Myanmar and the Indian Ocean region. At the stakeholder level, a consultation mechanism involving multi-stakeholder participation should be established by strengthening the docking of multi-stakeholder interests, coordinating the mechanism of China-Myanmar port docking, and creating a three-dimensional risk prevention mechanism for the Channel.

The scientific and sustainable utilization of marine space resources is of great significance for the high-quality development of China’s marine economy and the Ocean Power Strategy. This paper constructs the index system of marine space resources utilization intensity, analyzes the evolution law of China’s marine space resources utilization intensity and its influencing factors. The research results indicate that: (1) The overall utilization intensity of China’s marine space resources utilization is continuously increasing, and the imbalance in provincial utilization intensity of marine space resources was intensifying. (2) The utilization intensity of marine space resources in Tianjin increased significantly, while the utilization intensity of marine space resources in Shanghai fluctuated greatly. The utilization intensity of marine space resources in Zhejiang, Hainan, and Fujian remained at higher intensity and high intensity. The utilization intensity of marine space resources in Liaoning, Shandong, and Guangdong was at medium intensity and high intensity, while the utilization intensity of marine space resources in Jiangsu and Guangxi was at medium intensity and low intensity. The utilization intensity of marine space resources in Hebei remained at low intensity. (3) The overall utilization intensity of marine production space in 11 coastal provinces and cities was higher than that of marine ecological space and marine living space. The overall utilization intensity of marine living space shows a positive growth in 11 coastal provinces and cities, while the overall utilization intensity of marine ecological space shows a significant downward trend. (4) The economic level has the greatest positive effect on the utilization intensity of marine space resources, and industrial structure, government investment, and opening up also have significant positive effects on the utilization intensity of marine space resources. Coastline resources, marine-related employment, and environmental protection has negative effect on the utilization intensity of marine space resources.

[Objective] Rainfall is the driving force of hydraulic erosion in black soil sloping farmland. It is of great significance to study soil erosion characteristics under natural rainfall conditions for soil erosion control. [Methods] Based on 43 erosive rainfall events observed at different ridge-row runoff plots (3°, 5° and 7°) along the slope in Guangrong Small Watershed, Hailun City, Heilongjiang Province during 2021—2022, K-Mean clustering method was used to compare the characteristics of runoff and sediment transport under different rain patterns and slopes, and the influencing factors on runoff and sediment transport were discussed. [Results] The rainfall of short duration, heavy rain and light rainfall (rain type 3) is the main one, followed by the rainfall of medium duration, medium rain intensity and medium rainfall (rain type 2), and the rainfall of long duration, light rain intensity and heavy rainfall (rain type 1) rarely occurs. Under the same rain pattern, the cumulative runoff depth and sediment transport increased with the increase of slope. Under the same slope, different rainfall types have different responses to cumulative runoff depth. Overall, rainfall type 3 has the highest contribution (50.90%～57.90%), rainfall type 2 has the second contribution (37.60%～44.10%), and rainfall type 1 has the lowest. In the event of rain type 2, rainfall erosivity and slope have direct influence on runoff depth, and runoff depth and slope have direct influence on sediment transport. In the event of rain type 3, rainfall erosivity affects runoff depth and then sediment transport through direct and indirect effects. [Conclusion] For all rainfall-type events, rainfall erosivity and slope are the main controlling factors affecting the runoff depth, and the runoff depth and slope are the main controlling factors affecting the sediment transport.

The development of new technologies such as artificial intelligence has promoted the digital transformation of education around the world. ChatGPT, as a representative of generative artificial intelligence, poses new challenges to the field of education and also puts forward new requirements for teacher quality. Artificial intelligence literacy is the core qualitythat teachers need to adapt to the era of AI. Based on the analysis of the connotation of quality, teacher qualityand artificial intelligence literacy, teacher artificial intelligence literacy refers to the qualitythat teachers, as human-machine collaborative teachers, need to understand and use artificial intelligence educational application products in the context of the artificial intelligence era. In the AI era, teachers'artificial intelligence literacy includes three primary elements: AI knowledge, AI skills, and AI attitude and ethics, as well as fifteen secondary elements like knowledge of AI fact, knowledge of AI principle, skills of identifying AI, skills of analyzing AI, guarantee of student safety, and protection of student privacy, etc.It is effective tocultivate teachers' artificial intelligence literacy from three levels: government, school and teachers themselves.

False data injection attack (FDIA) is a serious threat to the security and stable operation of smart grids. In this paper, a FDIA detection algorithm that combines unsupervised and supervised learning is proposed, solving the problems of scarce labeled data and extremely imbalanced normal and attack samples. Firstly, contrastive learning is introduced to capture the features of a small amount of attack data, and it generates new attack samples to achieve data augmentation. Then, various unsupervised detection algorithms are used to perform feature self-learning on a large number of unlabeled samples, addressing the problem of scarce labeled samples. Finally, the features extracted by the unsupervised algorithm are fused with the historical feature set, and a supervised XGBoost classifier is constructed to identify and output the detection results. The results on the IEEE 30-node system show that the proposed method can enhance the stability of the FDIA detection model under scarce labeled samples and imbalanced data, compared with other FDIA detection algorithms. The proposed method can improve recognition accuracy and reduce false alarm rate.

Aiming at the contradiction between the rapidity requirement of online calculation of transient stability preventive control and the computational complexity of time-domain equations, a stacking ensemable learning driven optimization method for power system transient stability preventive control was proposed. Firstly, a transient stability estimator based on a stacking ensemble deep belief network was constructed to replace the nonlinear differential algebraic equation solution process required for transient stability determination. Secondly, the trained transient stability estimator was used as a transient stability constraint discriminator, which was embedded in the iterative optimization process of the Aptenodytes Forsteri optimization algorithm. Finally, with the goal of minimizing the cost of preventive control, a stacking ensemble learning driven power system transient stability preventive control optimization algorithm was established. The algorithm realized the efficient judgment of transient stability constraints in preventive control, and improved the decision-making level of preventive control for power generation rescheduling. Based on the IEEE39 bus system, the proposed preventive control method was verified by experiments. The results show that the method has achieved good results in both evaluation accuracy and calculation efficiency.

Error analysis of inertial navigation systems is one of the important tasks in inertial navigation research. Through error analysis, the contribution of each error in the system to the total error can be obtained. This work is particularly important in the rotary modulation inertial navigation system, because it is necessary to evaluate the suppression effect of the rotation strategy on various error sources through error analysis. Firstly, a state space model of the error has been established based on the system error model, and the total navigation error is divided into linear combinations of various error factors through recursion and decomposition. The derived covariance update equation can be used to quickly and accurately obtain the contribution of various errors including initial error and device error to the total system error. Simulation results of strapdown, single-axis and two-axis modulation systems verifies that the error propagation rules calculated by the proposed method are in agreement with the known conclusions. Simulation of different modulation strategies shows that the proposed method is fast and intuitive in evaluating rotation strategies.

Biotechnology is crucial for the sustainable development of the aquatic seed industry. Therefore, improving the innovation capability in aquatic breeding and making seed sources independent are significant for ensuring food security in China. This study summarizes the development status and problems of aquatic breeding in China and analyzes the status of research and application of seven types of biotechnology for aquatic breeding, namely, transgenic breeding, ploidy breeding, molecular-marker-assisted breeding, genomic selection breeding, genome editing breeding, molecular design breeding, and germline stem cell transplantation; future research and development demand for these technical fields in China is further analyzed. Moreover, future development goals and major tasks are suggested, including collecting, preserving, and accurately identifying excellent germplasm resources of aquatic organisms, profoundly analyzing the genetic basis and regulatory mechanism of critical traits, developing efficient and accurate breeding technologies, and achieving breakthroughs in the creation of new varieties. Furthermore, following suggestions are proposed: optimizing development policies of the aquatic seed industry, promoting technological innovation in aquatic breeding, establishing platforms for aquatic variety creation and transformation, and setting up special projects to accelerate technological innovation and development of the aquatic seed industry.

Objective To investigate the effect of Baduanjin exercise combined with Jue-tone Music therapy on anxiety and depression in patients with psoriasis vulgaris. Methods Totally 88 patients with psoriasis vulgaris who discharged from the hospital were randomly divided into three groups: control group (n=29), intervention group A (n=29) and intervention group B(n=30). The control group received routine follow-up after discharged from hospital, the intervention group A received Baduanjin exercise, and the intervention group B received Baduanjin exercise combined with Jue-tone music therapy. The Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS)were used to assess the anxiety and depression status of patients. Results At one month after discharge form hospital, scores of SAS and SDS in intervention group A and intervention group B were lower than those in the control group, respectively(P＜0. 05), and scores of SAS and SDS in intervention group B were lower than those intervention group A(P＜0. 05). Conclusion Baduanjin exercise combined with Jue-tone music therapy during follow-up is effective to relieve the anxiety and depression of patients with psoriasis. (目的 分析健身气功八段锦联合角调式音乐对寻常型银屑病患者焦虑抑郁症状的干预效果。方法 选取医院收治的寻常型银屑病出院患者88例为研究对象, 采用随机数字表法分为对照组(n=29)、干预1组(n=29)和干预2组(n=30), 对照组采用常规出院随访, 干预1组仅练习健身气功八段锦, 干预2组练习健身气功八段锦联合聆听角调式音乐。采用焦虑自评量表(SAS)和抑郁自评量表(SDS)评估患者焦虑抑郁程度。结果 出院后1个月时, 干预1组和干预2组SAS、SDS评分均低于对照组(P＜0. 05), 且干预2组SAS、SDS评分低于干预1组(P＜0. 05)。结论 在寻常型银屑病患者出院后采用中医特色护理手段, 可帮助患者调节不良情绪, 改善患者焦虑抑郁症状。)

This paper summarized the skin care process of a patient with sigmoid colon malignant tumor after two courses of chemotherapy and targeted therapy with Capecitabine and Cetuximab injection. The application of licorice oil, a traditional Chinese Medicine, instead of normal saline for debridement can promote the softening of scab and relieve the pain of debridement. During the treatment, comprehensive nursing interventions on mental health, dietary and home-based education were carried out to reduce the risk of recurrence. (本文总结1例抗肿瘤药物引起皮肤毒性反应患者的护理经验。应用中药制剂甘草油替代生理盐水进行清创, 促进痂皮软化, 减轻患者清创疼痛; 同时给予患者心理、饮食、居家护理指导, 避免复发。)

Spatial load forecasting faces the problems of multiple characteristic factors and data shortage. A spatial load forecasting method based on double-layer extreme gradient boosting (XGBoost) and data enhancement is proposed. Firstly, the area to be predicted is divided into several sub regions according to the supply range of feeder power. Secondly, a feature selection model based on double-layer XGBoost is constructed. The first layer XGBoost scores and sorts the features. The combined features are loaded into the second layer XGBoost for sub regional load forecasting. The best feature variables of each sub region are selected according to the load forecasting results. Then, the training set samples of each sub region are enhanced by the generative adversarial network (GAN), and the load of sub regions is forecasted through the extreme learning machine (ELM). Finally, the predicted values of sub regions are added to obtain the load of the region to be predicted. Taking local areas of Shanghai as an example, the simulated experiment and comparative analysis are carried out. The results show that the proposed method can solve the problems of characteristic variable selection and data shortage at the same time, and has high prediction accuracy.

As the typical provincial transmission power grid,Jiangsu power grid is faced with the pressures and challenges induced from system-integration of rapid developments of renewable energy during the energy transition period,which needs to be upgraded in "source-network-load-storage" and other aspects. Through the analysis of energy development from load,power supply,grid structure in Jiangsu,challenges faced by Jiangsu power grid such as insufficient transfer abilities of important transmission sections are put forward. Considering the large-scale integrated renewable energy and structure characteristics of Jiangsu transmission power grid,transmission-capacity demands of the Yangtze-river-crossing section during the "14th Five-Year Plan" and future are emphatically analyzed. Afterwards embedded DC transmission technology that both the transmission-and receiving-ends are located in Jiangsu AC network and distributed on both sides of the Yangtze River are proposed. Comparing with the traditional long-distance and high-capacity DC transmission technology constructed under the interconnection mode,the embedded DC transmission technology proposed in this paper usually uses the existing overhead transmission lines or existing/reserved AC cable channels to construct the AC-DC hybrid power grid in Jiangsu,greatly improving transmission capacities of important sections with limited transmission corridor spaces and power supply potential abilities of the existing power system to satisfy the development demands of Jiangsu power system.

Multiple Input Multiple Output (MIMO) detection algorithm is used to compensate the Mode Dependent Loss (MDL) in Mode Division Multiplexing (MDM) optical fiber channel. The problem of MIMO detection algorithm is that the computational complexity is too high and the performance is degraded with a large number of modes. This paper proposes to apply Massive-MIMO detection algorithms to the fiber channel, The algorithms include Minimum Mean Square Error (MMSE) , Conjugate Gradient (CG) , Gauss Seidel (GS) , and Alternating Direction Method of multipliers based Infinity-Norm (ADMIN) , and Optimized Coordinate Descent based BOX constraint (OCDBOX) . The result shows that the OCDBOX has the best Bit Error Rate (BER) performance in MDL-impaired MDM optical fiber communication system while higher complexity. The ADMIN has the second best BER performance and lower computational complexity. Therefore, the ADMIN detection algorithm can represent a good candidate in the MDM system with MDL.

In order to solve the problems of unreasonable node distribution and complex connection of pressure energy lines in the current mine ventilation network pressure energy distribution diagram, a new method with independent disjoint roads as the main skeleton, and the node distribution method of the mine ventilation network pressure energy graph distributed on both sides of the remaining connected nodes is proposed. According to the spatial relationship between independent disjoint roads and the remaining nodes and the remaining nodes, the drawing method of the branch shape between the nodes is analyzed and the drawing algorithm is designed. The drawing results of the drawing algorithm show that the algorithm can use the existing data to reasonably convert the mine ventilation network diagram into the pressure energy distribution diagram of the mine ventilation network, and the nodes in the pressure energy distribution diagram are distributed in an orderly manner, and the pressure energy lines between the nodes are connected normally, which can not only reflect the network relationship between nodes, but also reflect the pressure energy distribution of nodes. The algorithm can provide a reference for intelligent mine ventilation and underground fire prevention and risk avoidance.

In view of the problem that quadrature amplitude modulation has 1.53 dB capacity gap at the Shannon limit in high signal noise ratio, the paper proposes a joint shaping method of geometry and probability based on mutual information neural estimation. Geometric shaping and probability shaping are combined to improve the mutual information of the communication system. In this paper, the mutual information neural estimation is used to calculate the mutual information of the system, and the encoder of the transmitter is trained for the purpose of maximizing the mutual information, so as to realize geometric shaping and probability shaping. Through the simulation of Additive White Gaussian Noise (AWGN) channels with different signal noise ratios, it is proved that the performance of joint shaping of geometry and probability based on mutual information neural estimation is better than that of geometric shaping or probabilistic shaping separately. In AWGN channel with signal-to-noise ratio of 10 dB, the mutual information of the system has a gain of 0.041 7 bit/symbol over geometric shaping, and a gain of 0.027 9 bit/symbol compared over probability shaping.

In order to obtain the characteristic parameters of dampness status of resin impregnated paper (RIP),the time domain dielectric response technique is performed on the dampness status evaluation,and the RIP moisture contents are intensively studied based on polarization and depolarization current (PDC) method. Firstly,RIP insulation samples with different moisture contents are prepared in the laboratory and the PDC curves are measured. Then,the optimization algorithm combining genetic algorithm and interior point method is introduced,and the parameters of extended Debye model are obtained by Matlab simulation. Finally,two characteristic parameters of dampness status are extracted,which are the relaxation contribution coefficient of the maximum time constant branch A 9 and the stable depolarization charge quantity Q d-5000. Conclusions from the research results are as follows. The PDC curve moves upward as the moisture content increases. The dampness of the RIP insulation results in the increase of its conductivity and the decrease of its insulation resistance,absorption ratio andpolarization index. The parameters of the 9-branch extended Debye model are sensitive to the RIP insulation dampness status,and the A 9 shows a linear relationship with moisture content. The depolarization charge quantity is sensitive to moisture content,and the Q d-5000 shows an exponential relationship with moisture content.

Cryptographic cores are the key components to enforce information security properties related to confidentiality and integrity. Since the security of a cryptographic core implementation and the security of the cryptographic algorithm itself from the mathematical perspective are two different problems, cryptographic cores may contain hidden security vulnerabilities such as design flaws and side channels. Security analysis methods based on functional verification rely heavily on the quality of test vectors and usually have low test coverage, which is difficult to meet the security verification requirements of security-critical components like cryptographic cores. This work proposes a cryptographic core security verification and vulnerability detection method from the perspective of information flow security. The proposed method can accurately measure all logical information flows in cryptographic core designs to formally verify security properties such as confidentiality and integrity. It can detect potential security vulnerabilities in cryptographic implementations by capturing harmful information flows. Experimental results show that our information flow security verification method is effective in detecting sensitive information leakage caused by the design vulnerabilities and side channels in cryptographic cores.

The current electricity transaction process in the electricity market has problems such as high risk, time-consuming, and low efficiency. In order to solve such problems, an improved smart contract electricity transaction model based on blockchain is proposed. The blockchain is a decentralized database with advantages such as non-tampering and encryption security. The blockchain has the advantages of decentralization and high securing. The blockchain and smart contract are applied in the proposed model to improve the efficiency and security of the electricity transaction process. Firstly, the existing problems of the current electricity transaction model are analyzed. Risk assessment is carried out. A decentralized electricity transaction scenario is constructed. Secondly, the reliability coefficient is combined with smart contracts to establish an improved smart contract electricity transaction model based on blockchain. Finally, the feasibility of the model is verified by simulating electricity transaction. The results show that the improved smart contract electricity transaction model proposed is more efficient than the existing transaction model. The model effectively reduces the risk of being attacked and maintain the power market transaction order, thus providing a new idea for the electricity market transaction mode.

Telomerase reverse transcriptase is a subunit of telomerase, which plays an important role in activating telomerase and regulating cell cycle. Human telomerase reverse transcriptase(hTERT) is mainly expressed in germ cells, embryonic stem cells and tumor cells, only a few expressed in normal cell. hTERT is mainly located in nucleus and also distributed in mitochondria. hTERT migration from nucleus into mitochondria is called the mitochondrial translocation of hTERT. Mitochondrial translocation of hTERT functions in the process of apoptosis, immortalization and drug resistance. Control of hTERT is a potential breakthrough in the treatment of diseases.

Existing polyhedral compilation tools often use some simple heuristic strategies to find the optimal loop fusion decisions.It is necessary to manually adjust the loop fusion strategy to get the best performance for different programs.To solve this problem,a fusion strategy based on data reuse analysis is proposed for multi-core CPU platform.This strategy avoids unnecessary fusion constraints that affecting the mining of data locality.For different stages of scheduling,the parallelism constraint for diffe-rent parallel levels is proposed.And a tiling constraint for CPU cache optimization is proposed for statements with complex array accesses.Compared with the previous loop fuion strategies,this strategy takes into account the changes in spatial locality when calculating the fusion profits.This strategy is implemented based on the polyhedral compilation module Polly in the LLVM compilation framework,and some test cases in test suites such as Polybench are selected for testing.In the case of single-core testing,compared with the existing fusion strategies,the average performance is improved by 14.9%~62.5%.In the case of multi-core testing,compared with the existing fusion strategies,the average performance is improved by 19.7%~94.9%,and the speedup is up to 1.49x~3.07x.

Thermal barrier coating (TBC) is a kind of thermal insulation and protective ceramic material, which can effectively improve the working temperature and service life of aero-engine. It has important economic value and strategic position in this field. With the further improvement of thrust-to-weight ratio, the traditional YSZ coating no longer can meet the technical requirements of the new generation engine. In recent years, scholars both at home and abroad have shown that rare earth doping can improve the performance of TBCs to a certain extent. Therefore, rare earth doping modification has become the focus of the development of new high-performance TBCs. In this paper, the applications of rare earth doping in high-performance TBCs are summarized, with emphasis on the effects of rare earth doping on the mechanical, thermal-physical and corrosion resistance of TBCs to molten CMAS. The problem of performance deterioration of TBCs when rare earth is over doped and the deficiency in rare earth selection standard is discussed. Moreover, it is considered that the selection basis of rare earth doping amount and type will be the research focus of TBC materials in the next generation. How to further improves the performance of TBCs is the future development direction of rare earth doped TBCs.

Aiming at the application research of polar code in optical communication system, this paper proposes the combination of polar coding modulation and optical fiber Module Division Multiplexing (MDM) system. We construct an MDM system based on bit interleaved polar coding modulation, and study the performance of Maximum Likelihood (ML) detection algorithm. The simulation results show that the addition of polar code greatly improves the system performance. Compared with the MDM system without coding, the MDM system with bit interleaved polar coding modulation improves the system performance by about 8 dB under the same Mode Dependent Loss (MDL) . The paper also shows the performance of ML detection algorithm and Minimum Mean Square Error (MMSE) detection algorithm in MDM system. The impact of different mode loss on system performance is also studied. Compared with MMSE detection algorithm, ML detection algorithm improves the bit error performance by about 3 dB.

6-(4-chlorophenoxy)-tetrazolo[5,1-a]phthalazine is a national class I innovative antiepileptic drug candidate in clinical trials with independent intellectual property rights. The 1H, 13C and 15N NMR spectra of the compound were acquired at 500 MHz. Aided by GIAO (Gauge-Independent Atomic Orbital)-NMR quantum chemistry calculation, the chemical shifts of the compound were assigned, providing elaborate structural information of the compound. Linear regression comparison results showed good consistency between the theoretical predictions and the experimental data for structural elucidations.

Objective Discussion on the application value of a competence-based teaching mode in the teaching of prenatal ultrasound. Methods Eighty-seven people from a teaching hospital from July 2015 to December 2019 in the ultrasound were selected.Forty-five students in the experimental group were trained with a new model targeted at “post competence”, while forty-two students in the control group were trained on the traditional teaching mode. Results The theoretical and technical scores of the experimental group are higher than those of the control group.The total theoretical and technical scores of the students with working experience are higher than those of the non-experienced group.The total theoretical and skills scores of master candidates are higher than the undergraduate group. Conclusions The teaching mode targeting at“post competence” can achieve good results in prenatal ultrasound teaching.

Objective To investigate the expression of CD248 (endosialin) in clear cell renal cell carcinoma (ccRCC) tissues and its clinical significance. Methods We collected fresh specimens from 17 ccRCC tissues and adjacent tissues, as well as paraffin specimens from 115 ccRCC tissues and adjacent tissues. qRT-PCR was used to detect the expression of CD248 mRNA in 17 cases of ccRCC tissues and corresponding adjacent tissues. Immunohistochemistry was used to detect the level of CD248 protein in paraffin-embedded specimens of 115 ccRCC patients. The correlation of CD248 expression with clinicopathological indicators and prognosis of ccRCC patients were analyzed. Results Compared with adjacent noncancerous tissues, CD248 mRNA expression (P=0.0026) and the average tissue immune response score (P=0.0061) were significantly higher in ccRCC specimens. The positive signal of CD248 protein was localized in the cytoplasm and part of the nucleus. The overall survival (OS) of high CD248 expression group was significantly lower than that of low CD248 expression group (44.4 vs. 57.2 months, P=0.017). Conclusion CD248 expression may be involved in the development of ccRCC. Compared with adjacent tissues, CD248 is highly expressed in ccRCC tissues. ccRCC patients with high CD248 expression have shorter survival time.

As a strong candidate for the new type of non-volatile memories and artificial synaptic devices, memristor has a huge development prospect in aerospace, Mars exploration and other space science and application fields. Once large-scale application of memristor requires extremely stringent radiation resistance performance for the memristors. In order to improve the radiation resistance of memristors, it is necessary to explore the radiation effect mechanism and develop an effective radiation resistance technology. This paper summarizes the research status and trends of irradiation effects on memristors, describes the mechanism and analysis method of irradiation damage of memristor, and focuses on the irradiation effects of the memristors with transition metal oxide material system. Additionally, the possibility of scientific problems and key technologies are discussed, so as to provide some ideas for the radiation hardening and space application of memristor.

Aluminum (Al) can be easily contaminated or damaged after exposure in damp environments, which can adversely affect its aesthetic appearance and desired functionalities. To improve its corrosion resistance, a superhydrophobic coating was fabricated on Al by electrochemical anodization followed by modification with myristic acid. The surface morphology and chemical composition were characterized by using a field emission scanning electron microscope (FESEM) with attached energy dispersive X-ray spectrum (EDS). The surface wettability, mechanical stability as well as corrosion resistance were also investigated by contact angle measuring system, sandblasting test and electrochemical measurements. The results show that the optimal Al-based superhydrophobic coating with a static water contact angle of (155.2±0.5)° and a sliding angle of (3.5±1.3)° is obtained at the anodization voltage of 20V. The corresponding corrosion current density (Icorr) is reduced by 2 orders of magnitude and the corrosion potential (Ecorr) shifts from -0.629V to -0.570V compared to the bare Al substrate, indicating excellent corrosion resistance. Besides, the as-prepared optimal Al-based superhydrophobic coating also suggests good mechanical stability.

Based on the diamond and inorganic sol, spray-drying method was used to prepare diamond-vitrified bond composite powders and then the bulk samples were obtained after pressing and sintering the powders. The surface morphology and particle size distribution of the composite powders were examined by scanning electron microscope and laser particle size analyzer,the sintering temperature of the composites was selected with the aid of the comprehensive thermal analysis instrument,the bending strength, fracture morphology and crystal phases of sintered samples prepared by spray-drying method and melting method were characterized by motorized bending tester, scanning electron microscope and X-ray diffraction, respectively. The results show that the composite powders prepared by spray-drying are spherical,which is beneficial to mould forming. Their wide size distribution helps to improve the density of diamond-vitrified bond green body. The sintering temperature of the composites is 820℃.The bonding and wrapping of diamond can be realized at this temperature. With the increase of bond content, the bending strength of sintered samples prepared by two methods increases and porosity decreases. When the vitrified bond content is 32%(mass fraction), the microstructure of samples prepared by spray-drying is uniform and is easy to be crystallized, and the bending strength and porosity are 99.46MPa and 38.55%;while for samples obtained from melting method, the corresponding figures are 72.42MPa and 39.89%.

This paper presents a novel texture feature extraction method based on a Gabor filter and Three-Patch Local Binary Patterns (TPLBP) for Synthetic Aperture Rader (SAR) target recognition. First, SAR images are processed by a Gabor filter in different directions to enhance the significant features of the targets and their shadows. Then, the effective local texture features based on the Gabor filtered images are extracted by TPLBP. This not only overcomes the shortcoming of Local Binary Patterns (LBP), which cannot describe texture features for large scale neighborhoods, but also maintains the rotation invariant characteristic which alleviates the impact of the direction variations of SAR targets on recognition performance. Finally, we use an Extreme Learning Machine (ELM) classifier and extract the texture features. The experimental results of MSTAR database demonstrate the effectiveness of the proposed method.

Increasingly, detecting systems are facing the common problem of information processing owing to low SNR, low data rate, low resolution, and low information dimensions, and it is called the weak observation problem. This paper analyzes its origin and proposes the concept of information assembling by using the repetition and prediction properties of the object of interest. Then, the probability of the cloud inference method based on Bayesian theory is proposed to address a weak observation problem such as state estimation. Eventually several new requirements for sensor design, information processing, and system control are discussed, which are three crucial factors in information system design.

In view of problems of uncertainty and locality of information obtained by a single sensor in process of fault diagnosis of belt conveyor, the paper proposed a fault diagnosis method based on multi-sensor fuzzy information fusion. The method fuzzes information of belt conveyor obtained by temperature sensor, dust sensor and smoke sensor, fuses the information through synthetic operation and decision rule in fusion center, so as to get accurate estimation and judge of state of the belt conveyor. The experimental result shows that the method improves accuracy and reliability of the fault diagnosis of belt conveyor.

It is imperative to efficiently track and catalogue the extensive dense group space objects for space surveillance. As the main instrument for Low Earth Orbit (LEO) space surveillance, ground-based radar system is usually limited by its resolving power while tracking the small space debris with high dense population. Thus, the obtained information about target detection and observation will be seriously missed, which makes the traditional tracking method inefficient. Therefore, we conceived the concept of group tracking. The overall motional tendency of the group objects is particularly focused, while the individual object is simultaneously tracked in effect. The tracking procedure is based on the Bayesian frame. According to the restriction among the group center and observations of multi-targets, the reconstruction of targets’ number and estimation of individual trajectory can be greatly improved on the accuracy and robustness in the case of high miss alarm. The Markov Chain Monte Carlo Particle (MCMC-Particle) algorism is utilized for solving the Bayesian integral problem. Finally, the simulation of the group space objects tracking is carried out to validate the efficiency of the proposed method.

Objective To investigate the application value of Yishen Huayu Xugu prescriptionin the management of osteoporotic lumbar compression fracture among elderly patients. Methods From March 2022 to August 2023, all elderly patients with osteoporotic lumbar compression fractures were enrolled in our hospital and randomly assigned into two groups. The patients were diagnosed with kidney deficiency and blood stasis syndrome through physical identification. After admission, both groups (85 cases each) underwent percutaneous kyphoplasty. The control group received conventional Western medicine treatment post-surgery, while the observation group was administered Yishen Huayu Xugu prescription. This herbal formula was prepared by decocting 300 mL of juice in water, divided into two doses, and taken warmly after breakfast and dinner for a duration of 12 weeks. Therapeutic effects were compared after completion of the 12-week treatment period. Results After treatment, the serum levels of D-dimer (D-dimer, D-D) were (5.02 ± 0.63), interleukin-17 (IL-17) was (53.68 ± 5.47), p-collagen special sequence (p-CTX) was (0.37 ± 0.06, interleukin-6 (IL-6) was (69.38 ± 8.27) compared to the control group; bone morphogenetic protein-2 (BMP-2) was (2.69 ± 0.31), 25-hydroxyvitamin D was (58.93 ± 7.17), and vascular endothelial growth factor (VEGF) was (309.81 ± 51.49) which were higher than those in the control group with more sig-nificant improvement observed in the intervention group (P < 0.05). Bone mineral density (BMD) increased at both week 6 and week12 after treatment with a more pronounced improvement seen in the intervention group (P < 0.05). After treatment, the observation group exhibited a more significant reduction in the total Traditional Chinese Medicine ( TCM ) symptom score, Cobb Angle, and ODI, compared to the control group (P < 0.05 ). Furthermore, the observation group demonstrated a higher total effective rate of 95.29% (81/85) compared to 85.88% (73/85) in the control group after treatment, "with a statistically significant difference between the two groups (P < 0.05). Conclusion The Yishen Huayu Xugu prescription holds significant positive implications for this particular medication, as it exhibits enhanced efficacy in reducing inflammation, regulating bone metabolism, improving lumbar function, promoting disease amelioration, and enhancing clinical outcomes. [ABSTRACT FROM AUTHOR]

Objective To investigate the pollution characteristics of major heavy metals in PM2.5 in urban areas of Haikou City, and to assess their potential health risks to humans. Methods From 2021 to 2022, samples of atmospheric PM2.5 were monthly collected from the typical urban areas of Haikou, and the concentrations of nine heavy metal elements including arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), manganese (Mn), nickel (Ni), copper (Cu), vanadium (V), and zinc (Zn) were measured using the inductively coupled plasma mass spectrometry (ICP-MS). The health risk assessment of these heavy metals was conducted using a health risk model. Results The average mass concentration of PM2.5 in Haikou was (20.506±13.054) µg/m³, with a range of 4.000 to 64.000 µg/m³ during the year 2021 and 2022. The PM2.5 concentrations showed significant seasonal variations: highest in winter, followed by autumn and spring, and lowest in summer. The total concentration of the nine heavy metal elements ranged from 0.030 to 138.000 ng/m³, with Zn, Mn, and Pb having the highest concentrations, particularly notable during the autumn and winter seasons. Enrichment factor (EF) analysis indicated moderate enrichment (10-5 to 3.068x10-1), with the HQ values ordered as follows: Mn > Cd > Cr > As > Pb > V > Zn > Cu > Ni. The total non-carcinogenic hazard index (HI) ranged from 0.171 to 0.361. The inhalation incremental lifetime carcinogenic risk values (ILCR) for the four elements Cr, As, Cd, and Ni ranged from 2.911x10-7 to 1.558x10-5, with ILCR decreasing in that order. The total carcinogenic risk index (TR) varied between 1.502x10-5 and 3.169x10-5, with risk intensities for HI and TR in the order: children > adult males > adult females. Conclusions The average PM2.5 concentration in the Haikou urban area is lower than the 24-hour average concentration limit of Grade I (35 µg/m³) in the "Environmental Air Quality Standard" (GB 3095-2012), but still higher than the control standard recommended by the WHO in 2021 (15 µg/m³). The non-carcinogenic health risks of the nine heavy metal elements detected in PM2.5 are not significant, but Cr and As have potential carcinogenic risks, with children being more vulnerable than other populations. [ABSTRACT FROM AUTHOR]

Swamp eel (Monopterus albus) is an important freshwater culture fish in China and has the characteristic of hermaphroditism and natural sexual reversal. Currently, there is a lack of artificial varieties within swamp eel cultivation, and the fry of mainly rely on the wild catching. Gynogenesis, a method for rapidly obtaining fish population with stable heredity and excellent character, was explored in this study. Meiogynogenesis induction was established in swamp eel, resulting in the creation of three gynogenic populations characterized by deep-yellow coloration. Flow cytometry analysis showed that the cellular DNA contents of gynogenic eels were consistent with those of wild type fish, and chromosome counting confirmed the diploid nature with 48 chromosomes. Histological analysis demonstrated the development of ovaries in the gonads of gynogenic eels, indicating normal diploid functionality. Microsatellite diversity analysis showed that the effective number of alleles (Ne), Shannon's information index (I), polymorphism information content (PIC), observed heterozygosity (Ho) and expected heterozygosity (He) in gynogenic eels were significantly lower than those in the wild population. The genetic homozygosity in gynogenetic eels exhibited a significant improvement. The genetic distance increased and the genetic similarity decreased between gynogenetic groups. In summary, the gynogenetic population of the deep-yellow swamp eels provides new materials for breeding excellent varieties. [ABSTRACT FROM AUTHOR]

Medical image segmentation has broad application prospects in the field of medical image processing, providing auxiliary information for diagnosis and treatment by locating and segmenting interested organs, tissues, or lesion areas. However, there is a domain offset problem between different modalities of medical images, which can lead to a significant decrease in the performance of the segmentation model during actual deployment. Domain adaptation technology is an effective way to solve this problem, especially unsupervised domain adaptation, which has become a research hotspot in the field of medical image processing because it does not require target domain label information. At present, there are relatively few review reports on unsupervised domain adaptation research in medical image segmentation. Therefore, this paper summarizes, analyzes, and prospects the future of unsupervised domain adaptation research in medical image segmentation in recent years, hoping to help relevant researchers quickly understand and familiarize themselves with the current research status and trends in this field. [ABSTRACT FROM AUTHOR]

Opening agent is used in the production of plastic films, which can effectively improve the opening properties of the film. In this paper, four kinds of silica (SiO2) opening agents were synthesized by precipitation method, and four kinds of LLDPE/SiO2 masterbatch were prepared by melt blending with linear low density polyethylene (LLDPE) under the same processing conditions. The results show that the four kinds of opening agents can meet the requirements of anti-sticking and opening performance of LLDPE film, and the dynamic/static friction coefficients are all reduced to less than 0.11 (belonging to high smoothness). After compacting at 50 °C and 7 kPa for 24 h, there was no adhesion between the four LLDPE/SiO2 films, but pure LLDPE films had some adhesion. AFM test shows that there are micro pits near the submicron SiO2 opening agent particles, which play a key role in reducing negative pressure and van der Waals force, thus reducing the adhesion of LLDPE/SiO2 films. Based on the test data, a model of anti-sticking opening for LLDPE film is proposed, which is expected to be used to guide the production of opening agents with higher anti-sticking opening efficiency. [ABSTRACT FROM AUTHOR]

Aiming at the shortcomings of the existing methods of energy efficiency management level evaluation for hydropower stations, this paper introduces Analytic Hierarchy Process (AHP) method and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method into the evaluation process. The evaluation index system of energy efficiency management of hydropower station is constructed by considering the three aspects of economy, safety and management comprehensively. In order to overcome the shortcomings of the nine scale method, the paper uses the exponential scale method to determine the weight of each index. What's more, TOPSIS method and expert scoring method are used to score the quantitative indicators and the qualitative indicators, respectively, so as to further realize the comprehensive evaluation of the hydropower station energy efficiency management level. An actual hydropower station is taken as an example to analyze and calculate the score of the energy efficiency management level of the hydropower station from 2018 to 2022.The results show that the energy efficiency management level of the hydropower station is on the rise. [ABSTRACT FROM AUTHOR]

This paper introduces the construction background of intercity railway in Shenzhen Metropolitan Area and the operation and maintenance status of the signaling system, proposes the construction goal of the integrated intelligent operation and maintenance platform. By analyzing the operation and maintenance requirements of the equipment, a set of specific software and hardware construction schemes are given. After the completion of the platform, it is conducive to comprehensively improving the O&M and management level of the equipment, and is also conducive to the integration and optimal configuration of data resources. [ABSTRACT FROM AUTHOR]

Polyether polyol, toluene diisocyanate, diphenylmethane diisocyanate and plasticizer were used as raw materials to synthesize the prepolymer, and polyether polyol, dimethylthiotoluene diamine (DMTDA) and MOCA were used as raw materials to synthesize the curing agent. A two-component solvent-free polyurethane waterproof coating for railway bridges with high performance and environmental protection was prepared. When the molar ratio of TDI80 and MDI50 of isocyanate was 2:1, the root index of isocyanate was 1.15, the mass ratio of polyether polyol 3050 and polyether polyol 2000 was 2:1, and the molar ratio of DMTDA and MOCA was controlled at 1:2, high performance environmentally friendly polyurethane waterproof coating for high-speed railway bridge deck with tensile strength of 6.84 MPa, elongation at break of 535% and tear strength of 35.5 N/mm was prepared. [ABSTRACT FROM AUTHOR]

Li2O-Al2O3-SiO2 (LAS) system high crystallinity transparent glass ceramics with different ZrO2 content were prepared by conventional melt quenching and two-step crystallization approaches. The crystallization kinetics, phase evolution, structure and light transmittance of LAS glass ceramics were studied. The results show that when the content of ZrO2 increases to a certain amount, the crystallization mode of glass gradually changes from one-dimensional growth to two-dimensional growth, and its crystallization exothermic peak Tp value gradually increases, while its crystallization activation energy gradually decreases. In the process of crystal phase transformation, the glass precipitated crystal phases include lithium silicate (Li2SiO3) crystal, lithium permeating feldspar (LiAlSi4O10) crystal and lithium disilicate (Li2Si2O5) crystal. It is found that when lithium silicate (Li2SiO3) crystal is transformed into lithium disilicate (Li2Si2O5) crystal, the transmittance of glass increases. In additions, SEM results show that with the decrease of heating rate, the crystal size of glass precipitation gradually increases, and the crystal morphology is mainly spherical. [ABSTRACT FROM AUTHOR]

In this study, the cold shock treatment was used to induce triploid yellow drum (Nibea albiflora) and the ploidy was determined. The histology and gene expression analysis of reproduction-related genes were further used to characterize the gonadal development in triploid yellow drum. Firstly, the fertilized eggs were subjected to the cold shock treatment implemented at 3 °C for a period of 10 min commencing at post-fertilization 2.5min, and the fertilization rate and hatching rate in the cold shock treatment groups were (70.31±4.49)% and (21.5±6.63)%, respectively, which were significantly lower than that of diploid. Secondly, we found that the DNA relative content of triploid was 1.5 times larger than that of diploid by flow cytometer analysis, and the number of the chromosome in the triploid was 72, whereas the number of the chromosome in the diploid was 48 shown by karyotype analysis. The rate of the triploid was 100% in the present study. Thirdly, the gonadosomatic indexes of the triploids were significantly lower than that of the diploids. Histological results showed that the gonadal development of the triploids was slower than that of the diploids. At the age of 12 months, the testis and ovary of the diploids were both at the stage V, while the testis and ovary of the triploids were at stage III and stage I, respectively. Fourthly, the dmrt1 and vasa expression in the triploid testis and cyp19a expression in the triploid ovary were significantly lower than those in the diploid gonads (P<0.05), and the vasa expression in the triploid ovary was also lower than that in the diploids (P>0.05). The results indicated that the triploid yellow drum could be successfully induced by the cold shock treatment, and the gonadal development of the triploids was retarded. The results of present study will lay a basis for the application of the triploid in germ cell transplantation and the genetic improvement of yellow drum. [ABSTRACT FROM AUTHOR]

External apical root resorption is among the most common risks of orthodontic treatment, and it cannot be completely avoided and predicted. Risk factors causing orthodontic root resorption can generally be divided into patient- and treatment-related factors. Root resorption that occurs during orthodontic treatment is usually detected by radiographical examination. Mild or moderate root absorption usually does no obvious harm, but close attention is required. When severe root resorption occurs, it is generally recommended to suspend the treatment for 3 months for the cementum to be restored. To unify the risk factors of orthodontic root resorption and its clinical suggestions, we summarized the theoretical knowledge and clinical experience of more than 20 authoritative experts in orthodontics and related fields in China. After discussion and summarization, this consensus was made to provide reference for orthodontic clinical practice. [ABSTRACT FROM AUTHOR]

In order to prevent the faults caused by the overheating phenomena of gas insulated switchgear (GIS) contacts, it is necessary to monitor and predict the temperature of GIS contacts. In view of the problems that the temperature of contacts is not easy to be directly measured and the temperature is easily affected by the operation conditions and external factors, a prediction method of GIS contact temperature based on multiple parameters is proposed in this work. The temperature distribution law of GIS under different influencing factors is investigated by employing a three-dimensional simulation model. The influencing factors are contact resistance, load current, ambient temperature, wind speed, SF6 pressure and solar radiation intensity. The reliability of the model is validated by use of heat circuit model. The results indicate that the key factors to predict the contact temperature are the shell temperature rise, load current, wind speed, SF6 pressure and solar radiation intensity. At the same time, the influence of ambient temperature can be ignored. Further, the back propagation (BP) neural network is adopted to predict the temperature rise of the contacts with the above factors. The predicted temperature rise is compared with the calculated one of the model, and the error is in the range of -0.70~0.68 ℃. The method comprehensively takes into account the influence of various factors on the GIS temperature field, and it helps to give a reference for the temperature prediction of GIS contacts based on external sensors.

Objective To investigate the expression of COL6A1 in sarcoma tissue and its significance based on bioinformatics analysis. Methods The GEO database was used to download the GSE16088, GSE21122, and GSE49972 datasets to analyze the expression level of COL6A1-3. The Kaplan-Meier survival curves were used to analyze the impact of the expression level of COL6A1-3 on the prognosis of patients with sarcoma. A Spearman correlation analysis was performed using GSVA package to investigate the correlation between the expression level of COL6A1 and immune cell infiltration. The LinkedOmics database was used to analyze the genes co-expressed with COL6A1, and the ggstatsplot package of R software was used to investigate the correlation between COL6A1 and COL6A2. The ClusterProfiler package of R software was used to perform GO functional enrichment analysis and KEGG pathway analysis of the genes co-expressed with COL6A1. The GSEA analysis was used to investigate the important kinase, miRNA, and transcription factor targets of the genes co-expressed with COL6A1. Results Compared with normal tissue, there was a significant increase in the expression level of COL6A1 in osteosarcoma, soft tissue sarcoma, and clear cell sarcoma of the kidney. The survival analysis showed that the high expression of COL6A1 was associated with low overall survival rate and di-sease-specific survival rate (χ2=6.37,4.57,P

Inverted cone hydrocyclone, used as the downhole separator in the DOWS systems, could be affected by the particles in the produced water, which leads to the erosion on its inlet and the wall, damaging the wall quality, affecting the flow state, thus reducing the separation effect and affecting the service life. In order to investigate the erosion law of the solid particles on the hydrocyclone, the DPM model and the response surface method were used to simulate the interaction between the particles and the separator. The main parameters were found out in this paper along with a multiple regression fitting equation model of the maximum wear rate of the hydrocyclone's wall. The results show that under the action of sand-bearing well fluid, the flow velocity, the concentration and the size of the solid particles have significant effects on the inlet and cylindrical section of the downhole inverted cone hydroyclone with the tangential inlet. Within the range of operating parameters, the maximum wear rates of the inlet and cylindrical section increase significantly with the increase of these three parameters. The multiple regression fitting equation model can be used to predict the abrasion degree and service life of the inverted cone hydrocyclone, as the correlation coefficient R-squared is 0.9403, the maximum relative error is 4.91%, and the average relative error is 3.52%. [ABSTRACT FROM AUTHOR]