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Analgesic effect and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive inguinal hernia surgery 被引量:1
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作者 Qian-Xing Lou Ke-Ping Xu 《World Journal of Gastrointestinal Surgery》 2025年第3期161-170,共10页
BACKGROUND Currently,very few studies have examined the analgesic effectiveness and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for ... BACKGROUND Currently,very few studies have examined the analgesic effectiveness and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for inguinal hernia.AIM To investigate the analgesic effect and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for inguinal hernia.METHODS In this retrospective study,94 patients scheduled for laparoscopic minimally invasive surgery for inguinal hernia,admitted to Yiwu Central Hospital between May 2022 and May 2023,were divided into a control group(inhalation combined general anesthesia)and a treatment group(dexmedetomidine-assisted intrave-nous-inhalation combined general anesthesia).Perioperative indicators,analgesic effect,preoperative and postoperative 24-hours blood pressure(BP)and heart rate(HR),stress indicators,immune function levels,and adverse reactions were com-pared between the two groups.RESULTS Baseline data,including age,hernia location,place of residence,weight,monthly income,education level,and underlying diseases,were not significantly different between the two groups,indicating comparability(P>0.05).No significant difference was found in operation time and anesthesia time between the two groups(P>0.05).However,the treatment group exhibited a shorter postoperative urinary catheter removal time and hospital stay than the control group(P<0.05).Preoperatively,no significant differences were found in the visual analog scale(VAS)scores between the two groups(P>0.05).However,at 12,18,and 24 hours postoper-atively,the treatment group had significantly lower VAS scores than the control group(P<0.05).Although no significant differences in preoperative hemodynamic indicators were found between the two groups(P>0.05),both groups experienced some extent of changes in postoperative HR,diastolic BP(DBP),and systolic BP(SBP).Nevertheless,the treatment group showed smaller changes in HR,DBP,and SBP than the control group(P<0.05).Preoperative immune function indicators showed no significant differences between the two groups(P>0.05).However,postoperatively,the treatment group demonstrated higher levels of CD3+,CD4+,and CD4+/CD8+and lower levels of CD8+than the control group(P<0.05).The rates of adverse reactions were 6.38%and 23.40%in the treatment and control groups,respectively,revealing a significant difference(χ2=5.371,P=0.020).CONCLUSION Dexmedetomidine-assisted intravenous-inhalation combined general anesthesia can promote early recovery of patients undergoing laparoscopic minimally invasive surgery for inguinal hernia.It ensures stable blood flow,improves postoperative analgesic effects,reduces postoperative pain intensity,alleviates stress response,improves immune function,facilitates anesthesia recovery,and enhances safety. 展开更多
关键词 DEXMEDETOMIDINE Intravenous-inhalation combined general anesthesia Inguinal hernia Laparoscopic minimally invasive surgery Analgesia SAFETY
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Transforming Education with Photogrammetry:Creating Realistic 3D Objects for Augmented Reality Applications
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作者 Kaviyaraj Ravichandran Uma Mohan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期185-208,共24页
Augmented reality(AR)is an emerging dynamic technology that effectively supports education across different levels.The increased use of mobile devices has an even greater impact.As the demand for AR applications in ed... Augmented reality(AR)is an emerging dynamic technology that effectively supports education across different levels.The increased use of mobile devices has an even greater impact.As the demand for AR applications in education continues to increase,educators actively seek innovative and immersive methods to engage students in learning.However,exploring these possibilities also entails identifying and overcoming existing barriers to optimal educational integration.Concurrently,this surge in demand has prompted the identification of specific barriers,one of which is three-dimensional(3D)modeling.Creating 3D objects for augmented reality education applications can be challenging and time-consuming for the educators.To address this,we have developed a pipeline that creates realistic 3D objects from the two-dimensional(2D)photograph.Applications for augmented and virtual reality can then utilize these created 3D objects.We evaluated the proposed pipeline based on the usability of the 3D object and performance metrics.Quantitatively,with 117 respondents,the co-creation team was surveyed with openended questions to evaluate the precision of the 3D object created by the proposed photogrammetry pipeline.We analyzed the survey data using descriptive-analytical methods and found that the proposed pipeline produces 3D models that are positively accurate when compared to real-world objects,with an average mean score above 8.This study adds new knowledge in creating 3D objects for augmented reality applications by using the photogrammetry technique;finally,it discusses potential problems and future research directions for 3D objects in the education sector. 展开更多
关键词 Augmented reality education immersive learning 3D object creation PHOTOGRAMMETRY and StructureFromMotion
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Optimizing CNN Architectures for Face Liveness Detection:Performance,Efficiency,and Generalization across Datasets 被引量:1
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作者 Smita Khairnar Shilpa Gite +2 位作者 Biswajeet Pradhan Sudeep D.Thepade Abdullah Alamri 《Computer Modeling in Engineering & Sciences》 2025年第6期3677-3707,共31页
Face liveness detection is essential for securing biometric authentication systems against spoofing attacks,including printed photos,replay videos,and 3D masks.This study systematically evaluates pre-trained CNN model... Face liveness detection is essential for securing biometric authentication systems against spoofing attacks,including printed photos,replay videos,and 3D masks.This study systematically evaluates pre-trained CNN models—DenseNet201,VGG16,InceptionV3,ResNet50,VGG19,MobileNetV2,Xception,and InceptionResNetV2—leveraging transfer learning and fine-tuning to enhance liveness detection performance.The models were trained and tested on NUAA and Replay-Attack datasets,with cross-dataset generalization validated on SiW-MV2 to assess real-world adaptability.Performance was evaluated using accuracy,precision,recall,FAR,FRR,HTER,and specialized spoof detection metrics(APCER,NPCER,ACER).Fine-tuning significantly improved detection accuracy,with DenseNet201 achieving the highest performance(98.5%on NUAA,97.71%on Replay-Attack),while MobileNetV2 proved the most efficient model for real-time applications(latency:15 ms,memory usage:45 MB,energy consumption:30 mJ).A statistical significance analysis(paired t-tests,confidence intervals)validated these improvements.Cross-dataset experiments identified DenseNet201 and MobileNetV2 as the most generalizable architectures,with DenseNet201 achieving 86.4%accuracy on Replay-Attack when trained on NUAA,demonstrating robust feature extraction and adaptability.In contrast,ResNet50 showed lower generalization capabilities,struggling with dataset variability and complex spoofing attacks.These findings suggest that MobileNetV2 is well-suited for low-power applications,while DenseNet201 is ideal for high-security environments requiring superior accuracy.This research provides a framework for improving real-time face liveness detection,enhancing biometric security,and guiding future advancements in AI-driven anti-spoofing techniques. 展开更多
关键词 Face liveness detection cross-dataset generalization real-time face authentication transfer learning DenseNet201 VGG16 InceptionV3 deep learning
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Syn-Aug:An Effective and General Synchronous Data Augmentation Framework for 3D Object Detection
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作者 Huaijin Liu Jixiang Du +2 位作者 Yong Zhang Hongbo Zhang Jiandian Zeng 《CAAI Transactions on Intelligence Technology》 2025年第3期912-928,共17页
Data augmentation plays an important role in boosting the performance of 3D models,while very few studies handle the 3D point cloud data with this technique.Global augmentation and cut-paste are commonly used augmenta... Data augmentation plays an important role in boosting the performance of 3D models,while very few studies handle the 3D point cloud data with this technique.Global augmentation and cut-paste are commonly used augmentation techniques for point clouds,where global augmentation is applied to the entire point cloud of the scene,and cut-paste samples objects from other frames into the current frame.Both types of data augmentation can improve performance,but the cut-paste technique cannot effectively deal with the occlusion relationship between the foreground object and the background scene and the rationality of object sampling,which may be counterproductive and may hurt the overall performance.In addition,LiDAR is susceptible to signal loss,external occlusion,extreme weather and other factors,which can easily cause object shape changes,while global augmentation and cut-paste cannot effectively enhance the robustness of the model.To this end,we propose Syn-Aug,a synchronous data augmentation framework for LiDAR-based 3D object detection.Specifically,we first propose a novel rendering-based object augmentation technique(Ren-Aug)to enrich training data while enhancing scene realism.Second,we propose a local augmentation technique(Local-Aug)to generate local noise by rotating and scaling objects in the scene while avoiding collisions,which can improve generalisation performance.Finally,we make full use of the structural information of 3D labels to make the model more robust by randomly changing the geometry of objects in the training frames.We verify the proposed framework with four different types of 3D object detectors.Experimental results show that our proposed Syn-Aug significantly improves the performance of various 3D object detectors in the KITTI and nuScenes datasets,proving the effectiveness and generality of Syn-Aug.On KITTI,four different types of baseline models using Syn-Aug improved mAP by 0.89%,1.35%,1.61%and 1.14%respectively.On nuScenes,four different types of baseline models using Syn-Aug improved mAP by 14.93%,10.42%,8.47%and 6.81%respectively.The code is available at https://github.com/liuhuaijjin/Syn-Aug. 展开更多
关键词 3D object detection data augmentation DIVERSITY generalIZATION point cloud ROBUSTNESS
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Dual encoding feature filtering generalized attention UNET for retinal vessel segmentation
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作者 ISLAM Md Tauhidul WU Da-Wen +6 位作者 TANG Qing-Qing ZHAO Kai-Yang YIN Teng LI Yan-Fei SHANG Wen-Yi LIU Jing-Yu ZHANG Hai-Xian 《四川大学学报(自然科学版)》 北大核心 2025年第1期79-95,共17页
Retinal blood vessel segmentation is crucial for diagnosing ocular and cardiovascular diseases.Although the introduction of U-Net in 2015 by Olaf Ronneberger significantly advanced this field,yet issues like limited t... Retinal blood vessel segmentation is crucial for diagnosing ocular and cardiovascular diseases.Although the introduction of U-Net in 2015 by Olaf Ronneberger significantly advanced this field,yet issues like limited training data,imbalance data distribution,and inadequate feature extraction persist,hindering both the segmentation performance and optimal model generalization.Addressing these critical issues,the DEFFA-Unet is proposed featuring an additional encoder to process domain-invariant pre-processed inputs,thereby improving both richer feature encoding and enhanced model generalization.A feature filtering fusion module is developed to ensure the precise feature filtering and robust hybrid feature fusion.In response to the task-specific need for higher precision where false positives are very costly,traditional skip connections are replaced with the attention-guided feature reconstructing fusion module.Additionally,innovative data augmentation and balancing methods are proposed to counter data scarcity and distribution imbalance,further boosting the robustness and generalization of the model.With a comprehensive suite of evaluation metrics,extensive validations on four benchmark datasets(DRIVE,CHASEDB1,STARE,and HRF)and an SLO dataset(IOSTAR),demonstrate the proposed method’s superiority over both baseline and state-of-the-art models.Particularly the proposed method significantly outperforms the compared methods in cross-validation model generalization. 展开更多
关键词 Vessel segmentation Data balancing Data augmentation Dual encoder Attention Mechanism Model generalization
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Study on Color Difference of Color Reproduction of 3D Objects
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作者 GU Chong DENG Yi-qiang 《印刷与数字媒体技术研究》 北大核心 2025年第4期33-38,69,共7页
To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,a... To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,and TL84)on 3D color difference evaluations,50 glossy spheres with a diameter of 2cm based on the Sailner J4003D color printing device were created.These spheres were centered around the five recommended colors(gray,red,yellow,green,and blue)by CIE.Color difference was calculated according to the four formulas,and 111 pairs of experimental samples meeting the CIELAB gray scale color difference requirements(1.0-14.0)were selected.Ten observers,aged between 22 and 27 with normal color vision,were participated in this study,using the gray scale method from psychophysical experiments to conduct color difference evaluations under the four light sources,with repeated experiments for each observer.The results indicated that the overall effect of the D65 light source on 3D objects color difference was minimal.In contrast,D50 and A light sources had a significant impact within the small color difference range,while the TL84 light source influenced both large and small color difference considerably.Among the four color difference formulas,CIEDE2000 demonstrated the best predictive performance for color difference in 3D objects,followed by CMC(1:1),CIE94,and CIELAB. 展开更多
关键词 Color difference formula 3D objects Light source Gray scale Normalized residual sum of squares
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2024 US General Election and Changes in its Party Politics
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作者 Xie Tao 《Contemporary World》 2025年第1期44-48,共5页
The US 2024 general election ended with the Republican Party winning the presidential, House and Senate elections at the same time. In the presidential election, the Republican Party not only won more popular votes in... The US 2024 general election ended with the Republican Party winning the presidential, House and Senate elections at the same time. In the presidential election, the Republican Party not only won more popular votes in over 90% counties than in the 2020 general election, but also won seven highly contested swing States with greater edges. This also marks the first time since 2004 that the Republican Party has won a relative majority of popular votes in the presidential election. 展开更多
关键词 House elections US general election presidential election general election Senate elections republican party Republican Party popular votes
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A Generalized Satellite Digital Twin System for Satellite Operations
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作者 LIN Jiawei ZHANG Yujie +1 位作者 WU Xiaoming LIU Jianhua 《Aerospace China》 2025年第1期14-23,共10页
Digital twin shows broad application prospects in the aerospace field.This paper introduces a generalized satellite digital twin system in detail.With the innovative design concepts of modularization,generalization an... Digital twin shows broad application prospects in the aerospace field.This paper introduces a generalized satellite digital twin system in detail.With the innovative design concepts of modularization,generalization and modeling,on the one hand,the system has successfully achieved the reuse of software modules among different satellite models;on the other hand,it has achieved the reuse of software modules between the digital twin and the testing system,significantly improving the development efficiency of the digital twin system.The paper elaborates on the technical architecture and application fields of this digital twin system,and further prospects its future development.At the same time,through a real inorbit case,the engineering value of the digital twin system is strongly demonstrated. 展开更多
关键词 satellite operation generalIZATION digital twin
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Stress-Induced Endogenous Cannabinoid Signaling Contributes to Fear Generalization
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作者 Yanan Yue Xia Zhang Yuan Dong 《Neuroscience Bulletin》 2025年第6期1123-1126,共4页
The phenomenon of fear memory generalization can be defined as the expansion of an individual's originally specific fear responses to a similar yet genuinely harmless stimulus or situation subsequent to the occurr... The phenomenon of fear memory generalization can be defined as the expansion of an individual's originally specific fear responses to a similar yet genuinely harmless stimulus or situation subsequent to the occurrence of a traumatic event[1].Fear generalization within the normal range represents an adaptive evolutionary mechanism to facilitate prompt reactions to potential threats and to enhance the likelihood of survival. 展开更多
关键词 STRESS adaptive mechanism originally specific fear responses fear memory generalization endogenous cannabinoid signaling fear generalization adaptive evolutionary mechanism enhance likelihood survival
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StM:a benchmark for evaluating generalization in reinforcement learning
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作者 YUAN Kaizhao ZHANG Rui +5 位作者 PAN Yansong YI Qi PENG Shaohui GUO Jiaming HE Wenkai HU Xing 《High Technology Letters》 2025年第2期118-130,共13页
The challenge of enhancing the generalization capacity of reinforcement learning(RL)agents remains a formidable obstacle.Existing RL methods,despite achieving superhuman performance on certain benchmarks,often struggl... The challenge of enhancing the generalization capacity of reinforcement learning(RL)agents remains a formidable obstacle.Existing RL methods,despite achieving superhuman performance on certain benchmarks,often struggle with this aspect.A potential reason is that the benchmarks used for training and evaluation may not adequately offer a diverse set of transferable tasks.Although recent studies have developed bench-marking environments to address this shortcoming,they typically fall short in providing tasks that both ensure a solid foundation for generalization and exhibit significant variability.To overcome these limitations,this work introduces the concept that‘objects are composed of more fundamental components’in environment design,as implemented in the proposed environment called summon the magic(StM).This environment generates tasks where objects are derived from extensible and shareable basic components,facilitating strategy reuse and enhancing generalization.Furthermore,two new metrics,adaptation sensitivity range(ASR)and parameter correlation coefficient(PCC),are proposed to better capture and evaluate the generalization process of RL agents.Experimental results show that increasing the number of basic components of the object reduces the proximal policy optimization(PPO)agent’s training-testing gap by 60.9%(in episode reward),significantly alleviating overfitting.Additionally,linear variations in other environmental factors,such as the training monster set proportion and the total number of basic components,uniformly decrease the gap by at least 32.1%.These results highlight StM’s effectiveness in benchmarking and probing the generalization capabilities of RL algorithms. 展开更多
关键词 reinforcement learning(RL) generalIZATION BENCHMARK environment
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Honoring Ties,Embracing the Future Congratulatory message from the Consul General of Myanmar in Nanning on CAEXPO 2025
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《China Report ASEAN》 2025年第9期21-21,共1页
Mingalarpar!On behalf of the Consulate-General of the Republic of the Union of Myanmar in Nanning,I would like to express my sincerest congratulations to CAEXPO on reaching the remarkable milestone of over 20 years—a... Mingalarpar!On behalf of the Consulate-General of the Republic of the Union of Myanmar in Nanning,I would like to express my sincerest congratulations to CAEXPO on reaching the remarkable milestone of over 20 years—an incredible journey filled with numerous achievements. 展开更多
关键词 consulate general CAEXPO milestone CONGRATULATIONS TIES ACHIEVEMENTS Nanning future
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Transorbital craniocerebral injury caused by metallic foreign objects
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作者 Chongqing Yang Hongguang Cui +2 位作者 Xiawei Wang Chenying Yu Yan Long 《World Journal of Emergency Medicine》 2025年第3期277-279,共3页
Transorbital craniocerebral injury is a relatively rare type of penetrating head injury that poses a significant threat to the ocular and cerebral structures.^([1])The clinical prognosis of transorbital craniocerebral... Transorbital craniocerebral injury is a relatively rare type of penetrating head injury that poses a significant threat to the ocular and cerebral structures.^([1])The clinical prognosis of transorbital craniocerebral injury is closely related to the size,shape,speed,nature,and trajectory of the foreign object,as well as the incidence of central nervous system damage and secondary complications.The foreign objects reported to have caused these injuries are categorized into wooden items,metallic items,^([2-8])and other materials,which penetrate the intracranial region via fi ve major pathways,including the orbital roof (OR),superior orbital fissure (SOF),inferior orbital fissure(IOF),optic canal (OC),and sphenoid wing.Herein,we present eight cases of transorbital craniocerebral injury caused by an unusual metallic foreign body. 展开更多
关键词 transorbital craniocerebral injury ocular cerebral structures foreign objectas central nervous system damage penetrating head injury foreign objects metallic foreign objects clinical prognosis
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Depression levels of the general public increases during the COVID-19 pandemic in China:A web-based cross-sectional survey
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作者 Qin-Ming Qiu Yu Xiao 《World Journal of Psychiatry》 2025年第2期109-117,共9页
BACKGROUND The coronavirus disease 2019(COVID-19)outbreak lasted several months,having started in December 2019.This study aimed to report the impacts of various factors on the depression levels of the general public ... BACKGROUND The coronavirus disease 2019(COVID-19)outbreak lasted several months,having started in December 2019.This study aimed to report the impacts of various factors on the depression levels of the general public and ascertain how emotional measures could be affected by psychosocial factors during the COVID-19 pandemic.AIM To investigate the depression levels of the general public in China during the COVID-19 pandemic.METHODS A total of 2001 self-reported questionnaires about Beck Depression Inventory(BDI)were collected on August 22,2022 via the website.Each questionnaire included four levels of depression and other demographic information.The BDI scores and incidences of different depression levels were compared between various groups of respondents.χ2 analysis and the two-tailed t-test were used to assess categorical and continuous data,respectively.Multiple linear regressions and logistic regressions were employed for correlation analysis.RESULTS The averaged BDI score in this study was higher than that for the non-epidemic periods,as reported in previous studies.Even higher BDI scores and incidences of moderate and severe depression were recorded for people who were quarantined for suspected COVID-19 infection,compared to the respondents who were not quarantined.The participants who did not take protective measures were associated with higher BDI scores than those who made efforts to keep themselves relatively safer.Similarly,the people who did not return to work had higher BDI scores compared to those managed to.A significant association existed between the depression levels of the subgroups and each of the factors,except gender and location of residence.However,quarantine was the most relative predictor for depression levels,followed by failure to take preventive measures and losing a partner,either through divorce or death.CONCLUSION Based on these data,psychological interventions for the various subpopulations in the general public can be implemented during and after the COVID-19 pandemic.Other countries can also use the data as a reference. 展开更多
关键词 COVID-19 EPIDEMIC Depression general public Psychosocial factors
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Towards the Grassroots:Reform and Optimization of the Training Mode of General Medicine Talents in Traditional Chinese Medicine Colleges and Universities
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作者 Bingbing Chen Niqin Xiao +7 位作者 Heguo Yan Sanjin Zeng He Qian Xi Liu Kuanmeng Chi ZhaohuXie Zhaofu Li Jing Xie 《Journal of Contemporary Educational Research》 2025年第8期19-25,共7页
Primary healthcare service is the first line of defense to guard the health of the nation,and traditional Chinese medicine(TCM),with its characteristics of“simplicity,testing and inexpensiveness,”holistic outlook,an... Primary healthcare service is the first line of defense to guard the health of the nation,and traditional Chinese medicine(TCM),with its characteristics of“simplicity,testing and inexpensiveness,”holistic outlook,and the concept of treating the disease before it occurs,has a unique advantage in primary healthcare and a great demand for it.This paper analyzes the core challenges facing the cultivation of general medicine talents in TCM colleges and universities,such as the disconnection between cultivation goals and grassroots,the misalignment between practical ability and grassroots demand,and the lack of career attraction.On this basis,it puts forward a systematic reform path with the core concept of“rooting at the grassroots,highlighting characteristics,and strengthening competence”to cultivate talents that meet grassroots needs,aiming to provide theoretical references for TCM colleges and universities to cultivate excellent TCM talents who are“able to go down to the grassroots,be useful,stay in the field,and have development”,and to provide theoretical reference for the training of excellent TCM talents.The aim is to provide a theoretical reference for Chinese medicine colleges to cultivate excellent Chinese medicine talents who can“get down,use,stay and develop,”and to help the construction of a healthy China. 展开更多
关键词 Primary care Chinese medicine general medicine Talent training OPTIMIZATION
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Exploration of the Cultivation Mode of Applied,Composite,and Innovative Talents in General Medicine under the Background of New Medicine
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作者 Zhaoxiang Yu Xiping Yang +4 位作者 Ya Li Yuanyuan Jia Yaodong Li Shuijuan Zhang Xuekun Zhou 《Journal of Contemporary Educational Research》 2025年第6期250-256,共7页
The construction of new medicine is a strategic plan proposed by the Party and the state for the development of medical education in the new era,which brings new opportunities and challenges to the cultivation of gene... The construction of new medicine is a strategic plan proposed by the Party and the state for the development of medical education in the new era,which brings new opportunities and challenges to the cultivation of general medical talents.Based on the connotation of the new medical construction,we will promote the construction of a comprehensive medical talent training system.By creating a characteristic general education curriculum system,building a high-level clinical practice teaching base,creating an innovation and entrepreneurship education platform for the First Affiliated Hospital of Xi’an Medical University,and reforming and improving the internal incentive mechanism for teachers,we aim to cultivate comprehensive medical talents who are“useful,competent,capable,and able to stay,”and contribute to the construction of a healthy China. 展开更多
关键词 New Medicine general medical education Talent cultivation
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Gravitational Collapse and Expansion in the Newton Theory and General Relativity
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作者 Valery V. Vasiliev Leonid V. Fedorov 《Journal of Modern Physics》 2025年第2期294-309,共16页
The paper is devoted to the study of the gravitational collapse within the framework of the spherically symmetric problem in the Newton theory and general relativity on the basis of the pressure-free model of the cont... The paper is devoted to the study of the gravitational collapse within the framework of the spherically symmetric problem in the Newton theory and general relativity on the basis of the pressure-free model of the continuum. In application to the Newton gravitation theory, the analysis consists of three stages. First, we assume that the gravitational force is determined by the initial sphere radius and constant density and does not change in the process of the sphere collapse. The obtained analytical solution allows us to find the collapse time in the first approximation. Second, we construct the step-by-step process in which the gravitational force at a given time moment depends on the current sphere radius and density. The obtained numerical solution specifies the collapse time depending on the number of steps. Third, we find the exact value of the collapse time which is the limit of the step-by-step solutions and study the collapse and the expansion processes in the Newton theory. In application to general relativity, we use the space model corresponding to the special four-dimensional space which is Euclidean with respect to space coordinates and Riemannian with respect to the time coordinate only. The obtained solution specifies two possible scenarios. First, sphere contraction results in the infinitely high density with the finite collapse time, which does not coincide with the conventional result corresponding to the Schwarzschild geometry. Second, sphere expansion with the velocity which increases with a distance from the sphere center and decreases with time. 展开更多
关键词 Gravitational Collapse Newton Gravitation Theory general Relativity
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Insight into molecular and neural mechanisms of general anesthesia from the invertebrate model Drosophila melanogaster
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作者 Jia-Yue Gao Tao Luo Chang Liu 《Zoological Research》 2025年第4期792-810,共19页
General anesthesia(GA)is a pharmacologically induced,reversible state characterized by unconsciousness,amnesia,analgesia,and immobility in response to noxious stimuli.Accumulating evidence from animal models has eluci... General anesthesia(GA)is a pharmacologically induced,reversible state characterized by unconsciousness,amnesia,analgesia,and immobility in response to noxious stimuli.Accumulating evidence from animal models has elucidated diverse mechanisms of the action underlying GA,including disruption of large-scale brain network connectivity,regulation of multiple neural pathways,and modulation of specific receptors and ion channels.Despite advances in dissecting the neurobiological basis of anesthetic action,the precise cellular and circuit-level processes remain incompletely understood,limiting the development of safer and more effective strategies.Recent studies in Drosophila melanogaster,a genetically tractable model organism offering robust genetic analysis,advanced imaging capabilities,and compact neural architecture,have yielded critical insights into the conserved neurobiological mechanisms of GA,offering translational value for mammalian systems.This review outlines:1)experimental paradigms used to evaluate anesthetic sensitivity and behavioral responses in Drosophila;2)molecular targets and their mechanistic roles in mediating GA;and 3)neural circuit architectures and activity patterns shared by GA and sleep.Cross-species comparisons are integrated to highlight conserved mechanisms that may guide the development of more refined anesthetic strategies. 展开更多
关键词 general anesthesia Molecular mechanism Neural circuits Synaptic release SLEEP DROSOPHILA
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Observation on the Effect of Dexmedetomidine in Suppressing Cough Reflex During Tracheal Extubation in Pediatric Patients Undergoing General Anesthesia
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作者 Jian Wu Lijuan Chen Jinwen Zeng 《Journal of Clinical and Nursing Research》 2025年第10期248-253,共6页
Objective:To investigate the suppressive effect of dexmedetomidine on the cough reflex during tracheal extubation in pediatric patients undergoing general anesthesia and its impact on vital signs.Methods:A total of 60... Objective:To investigate the suppressive effect of dexmedetomidine on the cough reflex during tracheal extubation in pediatric patients undergoing general anesthesia and its impact on vital signs.Methods:A total of 60 pediatric patients undergoing elective surgery admitted to our hospital from January to August 2025 were selected and randomly divided into an observation group and a control group,with 30 cases in each group,using a random number table method.The control group received an intravenous infusion of 0.9% sodium chloride injection 30 minutes before the end of surgery,while the observation group received an intravenous pump infusion of dexmedetomidine(1μg/kg,diluted to 4μg/ml with normal saline).The severity of cough(graded from 0 to 3)and vital signs,including heart rate(HR),systolic blood pressure(SBP),diastolic blood pressure(DBP),and pulse oxygen saturation(SpO₂),were recorded 5 minutes before extubation,at the time of extubation,and 5 minutes after extubation in both groups.Results:The severity of cough in the observation group was significantly milder than that in the control group(P<0.05),with a significantly higher proportion of grade 0 cough in the observation group(23.33%vs 3.33%).At extubation and five minutes post-extubation,the observation group exhibited significantly lower HR,SBP,and DBP than the control group(P<0.05).In contrast,SpO_(2)levels remained comparable between the groups(P>0.05).Conclusion:Dexmedetomidine can effectively suppress the cough reflex during tracheal extubation in pediatric patients undergoing general anesthesia,reduce the severity of cough,stabilize hemodynamic parameters,and has no significant impact on respiratory function,demonstrating good clinical safety. 展开更多
关键词 Cough reflex DEXMEDETOMIDINE Tracheal extubation period general anesthesia Pediatric patients
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DDIRNet:robust radar emitter recognition via single domain generalization
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作者 WU Honglin LI Xueqiong +2 位作者 HUANG Junjie JIN Ruochun TANG Yuhua 《Journal of Systems Engineering and Electronics》 2025年第2期397-404,共8页
Automatically recognizing radar emitters from com-plex electromagnetic environments is important but non-trivial.Moreover,the changing electromagnetic environment results in inconsistent signal distribution in the rea... Automatically recognizing radar emitters from com-plex electromagnetic environments is important but non-trivial.Moreover,the changing electromagnetic environment results in inconsistent signal distribution in the real world,which makes the existing approaches perform poorly for recognition tasks in different scenes.In this paper,we propose a domain generaliza-tion framework is proposed to improve the adaptability of radar emitter signal recognition in changing environments.Specifically,we propose an end-to-end denoising based domain-invariant radar emitter recognition network(DDIRNet)consisting of a denoising model and a domain invariant representation learning model(IRLM),which mutually benefit from each other.For the signal denoising model,a loss function is proposed to match the feature of the radar signals and guarantee the effectiveness of the model.For the domain invariant representation learning model,contrastive learning is introduced to learn the cross-domain feature by aligning the source and unseen domain distri-bution.Moreover,we design a data augmentation method that improves the diversity of signal data for training.Extensive experiments on classification have shown that DDIRNet achieves up to 6.4%improvement compared with the state-of-the-art radar emitter recognition methods.The proposed method pro-vides a promising direction to solve the radar emitter signal recognition problem. 展开更多
关键词 radar emitter recognition domain generalization DENOISING contrastive learning data augmentation.
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Thirst experience and nursing needs in older patients after general anesthesia for gastrointestinal surgery:A qualitative study
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作者 Ting Li Wen-Hui Dong +2 位作者 Shuo Wang Ying Wu Shu-Yan Wang 《World Journal of Gastrointestinal Surgery》 2025年第5期257-265,共9页
BACKGROUND Older patients often experience thirst after general anesthesia for gastrointestinal surgery,particularly during the post-anesthesia care unit(PACU)phase.Thirst not only compromises patient comfort but also... BACKGROUND Older patients often experience thirst after general anesthesia for gastrointestinal surgery,particularly during the post-anesthesia care unit(PACU)phase.Thirst not only compromises patient comfort but also induces anxiety,which may hinder recovery.Although previous studies have addressed postoperative thirst,research specifically examining thirst experiences and nursing needs in older patients remains limited.AIM To explore thirst experiences and nursing needs of older PACU patients following gastrointestinal surgery,aiming to inform targeted interventions.METHODS This study employed a phenomenological approach within a qualitative research framework.A purposeful sampling method was used to select 12 older patients who underwent gastrointestinal surgery under general anesthesia at a tertiary hospital in Shanghai between November and December 2024.Data were collected through semi-structured interviews and analyzed using Colaizzi’s seven-step method.Themes were extracted from the interview data.RESULTS Analysis of the interview data identified four main themes and eight subthemes:(1)Intense sensations of thirst post-surgery(subjective experience of thirst and duration of thirst);(2)Emotional experiences of thirst-related discomfort(anxiety,irritability,and helplessness);(3)Practical challenges in relieving thirst(limitations of current interventions and nursing response time);and(4)Patient expectations of nursing care(desire for more timely interventions and expectation for more proactive attention from nursing staff).CONCLUSION Older patients frequently experience substantial thirst discomfort after gastrointestinal surgery under general anesthesia.A multidisciplinary perioperative intervention plan is essential to alleviate these symptoms and enhance postoperative comfort. 展开更多
关键词 Older people general anesthesia Gastrointestinal surgery Thirst experience NURSING Qualitative research
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