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Small particle drug-eluting beads-transarterial chemoembolization combined with targeted therapy in the clinical treatment of unresectable liver cancer
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作者 Jing-Song Qi Peng Zhao +2 位作者 Xiao-Bo Zhao Yong-Li Zhao Ying-Chang Guo 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第10期4157-4165,共9页
BACKGROUND Liver cancer is a highly malignant tumor with significant clinical impact.Chemotherapy alone often yields suboptimal outcomes in both the short and long term,characterized by high rates of local recurrence ... BACKGROUND Liver cancer is a highly malignant tumor with significant clinical impact.Chemotherapy alone often yields suboptimal outcomes in both the short and long term,characterized by high rates of local recurrence and distant metastasis,leading to a poor long-term prognosis.AIM To evaluate the clinical efficacy of small particle drug-eluting beads-transarterial chemoembolization(DEB-TACE)combined with targeted therapy for the treatment of unresectable liver cancer.METHODS We analyzed clinical data from 74 patients with unresectable liver cancer admitted between January 2019 and December 2020.Based on the different treatment regimens administered,patients were divided into the control(36 patients receiving sorafenib alone)and joint(38 patients receiving small particle DEB-TACE combined with sorafenib)groups.We compared liver function indicators[alanine aminotransferase(ALT),aspartate aminotransferase(AST),total bilirubin(TBIL),albumin(ALB)]and serum tumor markers[alpha fetoprotein(AFP)]before and after treatment in both groups.Short-term efficacy measures[complete response(CR),partial response,progression disease,stable disease,objective response rate(ORR),and disease control rate(DCR)]were assessed post-treatment.Long-term follow-up evaluated median overall survival(OS),progression-free survival(PFS),and adverse reaction rates between the two groups.RESULTS One month post-treatment,the joint group demonstrated significantly higher rates of CR,ORR,and DCR compared to the control group(P<0.05).Three days after treatment,the joint group showed elevated levels of ALT,AST,and TBIL but reduced levels of ALB and AFP compared to the control group(P<0.05).The median OS was 18 months for the control group and 25 months for the joint group,while the median PFS was 15 months for the control group and 22 months for the joint group,with significant differences observed(log-rank:χ2=7.824,6.861,respectively;P=0.005,0.009,respectively).The incidence of adverse reactions was not significantly different between the groups(P>0.05).CONCLUSION The combination of small particle DEB-TACE and sorafenib significantly improves both short-and long-term outcomes in the treatment of unresectable liver cancer while preserving liver function. 展开更多
关键词 small particle Drug-eluting beads-transarterial chemoembolization SORAFENIB TREATMENT Unresectable liver cancer
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Seismic performance evaluation of water supply pipes installed in a full-scale RC frame structure based on a shaking table test 被引量:1
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作者 Wu Houli Guo Endong +2 位作者 Wang Jingyi Dai Xin Dai Chenxi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期163-178,共16页
As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scal... As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scale reinforced concrete(RC)frame structure.Different material pipes and different methods for penetrating the reinforced concrete floors are combined to evaluate the difference in seismic performance.Floor response spectra and pipe acceleration amplification factors based on test data are discussed and compared with code provisions.A seismic fragility study of displacement demand is conducted based on numerical simulation.The acceleration response and displacement response of different combinations are compared.The results show that the combination of different pipe materials and different passing-through methods can cause obvious differences in the seismic response of indoor riser pipes. 展开更多
关键词 water supply pipe different materials shaking table test amplification factor seismic fragility
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Prevalence of Enteric Pathogens Associated with Infections among Table Egg Consumers in Some Primary Health Establishments in the Center Region of Cameroon
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作者 Mariane Lucie Ngueguim Bernard Viban Tangwa +2 位作者 Victor Ngu Ngwa Albert Ngakou Abdoulmoumini Mamoudou 《Advances in Infectious Diseases》 CAS 2024年第3期606-619,共14页
Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains o... Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains of stomach disorders after egg consumption. Data related to sociodemographic characteristics and other factors were collected using a structured based questionnaire. Stool culture of utmost importance in stomach disorders patients and serum were collected for typhoid serological test. Results: A total of 207 participants took part in the survey, Results indicated nontyphoidal Salmonella infections were highest in the 3 areas of study with Mfoundi (73.44%) having the highest level of infection compared to other bacterial infection. other enteric bacteria associated to this infection were E. coli serotype 157, Aeromonas, Citrobacter freundii, Enterobacter cloaca and typhi salmonella. Meanwhile salmonelosis caused by typhic salmonella had highest prevalence in the Lekie Division (13.11%) as a result of poor hygienic practices associated with the conservation and preparation of eggs, Stool culture was observed to detect more positive cases in the diagnosis of typhoid fever than Widal test, but with no statistically significant (p > 0.05) difference between the stool culture and Widal test in the 3 areas of study. Conclusion: this study revealed that egg consumers are pruned to enteric bacterial and salmonella infections depending on how and where egg is consumed. 展开更多
关键词 Enteric Pathogens table Eggs Consumption Center Region Cameroon
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Accelerated generation of holograms with ultra-low memory symmetrically high-compressed look-up table
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作者 杨燕 朱建英 +1 位作者 孙敏远 毕勇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期466-471,共6页
Computer-generated holography technology has been widely applied,and as research in this field deepens,the demand for memory and computational power in small AR and VR devices continues to increase.This paper presents... Computer-generated holography technology has been widely applied,and as research in this field deepens,the demand for memory and computational power in small AR and VR devices continues to increase.This paper presents a hologram generation method,i.e.,a symmetrically high-compressed look-up table method,which can reduce memory usage by50%.In offline computing,half of the basic horizontal and vertical modulation factors are stored,halving the memory requirements without affecting inline speed.Currently,its potential extends to various holographic applications,including the production of optical diffraction elements. 展开更多
关键词 computergenerated hologram look-up table HOLOGRAPHY
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The Periodic Table of Primes
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作者 Han-Lin Li Shu-Cherng Fang Way Kuo 《Advances in Pure Mathematics》 2024年第5期394-419,共26页
Over millennia, nobody has been able to predict where prime numbers sprout or how they spread. This study establishes the Periodic Table of Primes (PTP) using four prime numbers 2, 3, 5, and 7. We identify 48 integers... Over millennia, nobody has been able to predict where prime numbers sprout or how they spread. This study establishes the Periodic Table of Primes (PTP) using four prime numbers 2, 3, 5, and 7. We identify 48 integers out of a period 2×3×5×7=210 to be the roots of all primes as well as composites without factors of 2, 3, 5, and 7. Each prime, twin primes, or composite without factors of 2, 3, 5, and 7 is an offspring of the 48 integers uniquely allocated on the PTP. Three major establishments made in the article are the Formula of Primes, the Periodic Table of Primes, and the Counting Functions of Primes and Twin Primes. 展开更多
关键词 PRIMES COMPOSITES the Periodic table of Primes
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Postoperative efficacy,safety,predictability,and visual quality of implantable collamer lens implantation versus small incision lenticule extraction in myopic eyes:a Meta-analysis 被引量:4
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作者 Hong-Yu Li Zi Ye Zhao-Hui Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第3期442-452,共11页
AIM:To compare the postoperative efficacy,safety,predictability,and visual quality of implantable collamer lens(ICL)implantation versus small incision lenticule extraction(SMILE)in myopia eyes.METHODS:Pub Med,EMBASE,W... AIM:To compare the postoperative efficacy,safety,predictability,and visual quality of implantable collamer lens(ICL)implantation versus small incision lenticule extraction(SMILE)in myopia eyes.METHODS:Pub Med,EMBASE,Web of Science,Cochrane Library and several Chinese databases were searched at May 2021 to select relevant studies in comparison of clinical outcomes between ICL implantation and SMILE for myopia.The primary outcomes were efficacy,safety,and predictability.And the secondary outcomes were postoperative higher-order ocular aberrations(HOAs),modulation transfer function cutoff frequency(MTF),objective scatter index(OSI),contrast sensitivity and a quality of vision(Qo V)questionnaire.RESULTS:A total of 1036 eyes from 10 studies,of which 503 eyes underwent ICL implantation and 533 eyes underwent SMILE,were enrolled in this Meta-analysis.Pooled results revealed that ICL group had a better safety index and post-corrected distance visual acuity(CDVA)(P=0.007,<0.00001,respectively),and a lower percentage of eyes with a postoperative CDVA lost 1 line(P=0.007)than the SMILE group.No significant differences were found in comparison of the other primary outcomes.In the longterm follow-up(>6mo),ICL group had a lower total HOA,coma,and spherical aberration than SMILE group(P=0.003,<0.00001,0.04).Yet higher trefoil was found in ICL group at 6mo after surgery(P=0.003).Additionally,ICL group also had a higher MTF value(P=0.02),and a higher contrast sensitivity score for spatial frequencies of 1.5,6,and 12 cpds(P=0.02,0.005,0.02,respectively).And it also had a lower score of bothersome in Qo V questionnaire than SMILE group(P=0.003).CONCLUSION:ICL implantation and SMILE have similar and comparable outcomes in term of the efficacy and predictability for correcting high myopia.However,ICL group is relatively safer and also has better visual quality in comparison of SMILE group. 展开更多
关键词 implantable collamer lens small incision lenticule extraction MYOPIA refractive surgery META-ANALYSIS
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Opinions of Students on the Contribution of the DIVA 3D Virtual Dissection Table to the Teaching of Anatomy at the Faculty of Medicine and Odontostomatology of Bamako
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作者 Abdoulaye Kanté Tata Touré +8 位作者 Ousmane Toumany Chérif Haidara Uhl Jean François Mariam Daou Mamadou A. Keita Bakary Keïta Bréhima Bengaly Drissa Traoré Adégné Togo Nouhoum Ongoïba 《Forensic Medicine and Anatomy Research》 2024年第2期13-25,共13页
Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from Nov... Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from November 1 to December 30, 2023 at the clinical and morphological anatomy laboratory of the Faculty of Medicine and Odontostomatology of Bamako. Included in this study were students who participated in practical and tutorial sessions. The variables studied during this study were: the previous performance of dissection on a cadaver by the students, the opinion of the students on dissection on a cadaver, the replacement of dissection on a cadaver by virtual dissection in the absence of a body, the level student satisfaction. Results: We surveyed 130 participants. The average age was 22 ± 0.2 years with extremes of 17 and 29 years. 95.3% of participants were students. According to 66.7% of participants, virtual dissection is a good palliative in the absence of a corpse. 95.3% of participants found using the virtual dissection table easy with an average of 7.88 ± 1.4. The overall assessment was well rated by 99.3% of participants. Conclusion: According to the results of this study, the virtual dissection table should be improved by integrating commented videos. The use of the DIVA 3D virtual dissection table during practical and tutorial sessions is well appreciated by the students. We believe that the teaching of anatomy using 3D digital technology should be included in the study programs of the Faculty of Medicine and Odontostomatology. 展开更多
关键词 Student Opinion CONTRIBUTION DIVA 3D Virtual Dissection table Anatomy Teaching FMOS
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Improving Video Watermarking through Galois Field GF(2^(4)) Multiplication Tables with Diverse Irreducible Polynomials and Adaptive Techniques
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作者 Yasmin Alaa Hassan Abdul Monem S.Rahma 《Computers, Materials & Continua》 SCIE EI 2024年第1期1423-1442,共20页
Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4))... Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4)),and their interaction with distinct irreducible polynomials.The primary aim is to enhance watermarking techniques for achieving imperceptibility,robustness,and efficient execution time.The research employs scene selection and adaptive thresholding techniques to streamline the watermarking process.Scene selection is used strategically to embed watermarks in the most vital frames of the video,while adaptive thresholding methods ensure that the watermarking process adheres to imperceptibility criteria,maintaining the video's visual quality.Concurrently,careful consideration is given to execution time,crucial in real-world scenarios,to balance efficiency and efficacy.The Peak Signal-to-Noise Ratio(PSNR)serves as a pivotal metric to gauge the watermark's imperceptibility and video quality.The study explores various irreducible polynomials,navigating the trade-offs between computational efficiency and watermark imperceptibility.In parallel,the study pays careful attention to the execution time,a paramount consideration in real-world scenarios,to strike a balance between efficiency and efficacy.This comprehensive analysis provides valuable insights into the interplay of GF multiplication tables,diverse irreducible polynomials,scene selection,adaptive thresholding,imperceptibility,and execution time.The evaluation of the proposed algorithm's robustness was conducted using PSNR and NC metrics,and it was subjected to assessment under the impact of five distinct attack scenarios.These findings contribute to the development of watermarking strategies that balance imperceptibility,robustness,and processing efficiency,enhancing the field's practicality and effectiveness. 展开更多
关键词 Video watermarking galois field irreducible polynomial multiplication table scene selection adaptive thresholding
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Evaluation of the effects of EPS composite soil replacement on the dynamic performance of caisson structure using shaking table tests
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作者 Gao Hongmei Ji Zhanpeng +3 位作者 Zhang Xinlei Zhang Shushan Wang Zhihua Shen Guangming 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期829-843,共15页
The seismic performance of a caisson structure under two types of models with a saturated sandy foundation(CSS)and an expanded polystyrene(EPS)composite soil foundation(CES)are studied using shaking table tests.The ma... The seismic performance of a caisson structure under two types of models with a saturated sandy foundation(CSS)and an expanded polystyrene(EPS)composite soil foundation(CES)are studied using shaking table tests.The macro phenomena of the two different foundation models are described and analyzed.The effects of the replacement of EPS composite soil on seismic-induced liquefaction of backfill and the dynamic performance of a caisson structure are evaluated in detail.The results show that the excess pore water pressure generation in the CES is significantly slower than that in the CSS during the shaking.The dynamic earth pressure acting on the caisson has a triangular shape.The response of horizontal acceleration,displacement,settlement,and rotation angle of the caisson in the CES is smaller than that in the CSS,which means the caisson in the CES has a better seismic performance.Furthermore,the out-of-phase phenomenon between dynamic earth thrust and inertial force in the CES is more obvious than that in the CSS,which is beneficial to reduce the lateral force and improve the stability of the caisson structure. 展开更多
关键词 EPS composite soil foundation Caisson-type quay wall shaking table test phase difference rotation angle
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Numerical analysis on seismic performance of underground structures in liquefiable interlayer sites from centrifuge shaking table test
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作者 Yan Guanyu Xu Chengshun +2 位作者 Zhang Zihong Du Xiuli Wang Xuelai 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期781-798,共18页
When an underground structure passes through a liquefiable soil layer,the soil liquefaction may pose a significant threat to the structure.A centrifuge shaking table test was performed to research the seismic response... When an underground structure passes through a liquefiable soil layer,the soil liquefaction may pose a significant threat to the structure.A centrifuge shaking table test was performed to research the seismic response of underground structures in liquefiable interlayer sites,and a valid numerical model was obtained through simulation model test.Finally,the calibrated numerical model was used to perform further research on the influence of various distribution characteristics of liquefiable interlayers on the seismic reaction of underground structures.The key findings are as follows.The structure faces the most unfavorable condition once a liquefiable layer is located in the middle of the underground structure.When a liquefiable layer exists in the middle of the structure,the seismic reactions of both the underground structure and model site will increase with the rise of the thickness of the liquefiable interlayer.The inter-story drift of the structure in the non-liquefiable site is much smaller than that in the liquefiable interlayer site.The inter-story drift of the structure is not only associated with the site displacement and the soil-structure stiffness ratio but also closely associated with the slippage of the soil-structure contact interface under the condition of large deformation of the site. 展开更多
关键词 centrifuge shaking table test underground structure liquefiable interlayer sites seismic response validation of numerical model
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A novel control strategy for reproducing the floor motions of high-rise buildings by earthquake-simulating shake tables
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作者 Yuteng Cao Zhe Qu Xiaodong Ji 《Earthquake Research Advances》 CSCD 2024年第1期67-75,共9页
To enable the experimental assessment of the seismic performance of full-scale nonstructural elements with multiple engineering parameters(EDPs),a three-layer testbed named Nonstructural Element Simulator on Shake Tab... To enable the experimental assessment of the seismic performance of full-scale nonstructural elements with multiple engineering parameters(EDPs),a three-layer testbed named Nonstructural Element Simulator on Shake Table(NEST)has been developed.The testbed consists of three consecutive floors of steel structure.The bottom two floors provide a space to accommodate a full-scale room.To fully explore the flexibility of NEST,we propose a novel control strategy to generate the required shake table input time histories for the testbed to track the target floor motions of the buildings of interest with high accuracy.The control strategy contains two parts:an inverse dynamic compensation via simulation of feedback control systems(IDCS)algorithm and an offline iteration procedure based on a refined nonlinear numerical model of the testbed.The key aspects of the control strategy were introduced in this paper.Experimental tests were conducted to simulate the seismic responses of a full-scale office room on the 21^(st)floor of a 42-story high-rise building.The test results show that the proposed control strategy can reproduce the target floor motions of the building of interest with less than 20%errors within the specified frequency range. 展开更多
关键词 Shake table test Nonstructural element High-rise building Open-loop IDCS algorithm Off-line iteration
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Kinetic and thermodynamic synergy of organic small molecular additives enables constructed stable zinc anode 被引量:2
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作者 Yang Gao Mingshan Wang +10 位作者 Hao Wang Xinpeng Li Yuanwei Chu Zhicheng Tang Yuanlong Feng Jiaqi Wang Yong Pan Zhiyuan Ma Zhenliang Yang Dan Zhou Xing Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期62-72,共11页
An organic small molecule additive zinc formate is introduced to construct stable Zn metal interphase by electrochemical kinetic control and thermodynamic adjustment.It partially forms a water-formate concomitant dipo... An organic small molecule additive zinc formate is introduced to construct stable Zn metal interphase by electrochemical kinetic control and thermodynamic adjustment.It partially forms a water-formate concomitant dipole layer at the internal Helmholtz electrical double layers(HEDLs) under the preferential adsorption function of formate on Zn surface,reducing the occurrence of side reactions at phase interface.Meanwhile,free formate in HEDLs regulates the Zn^(2+) solvation sheath structure to accelerate the desolvation,transference,and deposition kinetics of Zn^(2+).Besides,the hydrolysis reaction of zinc formate increases the hydrogen evolution overpotential,inhibiting the thermodynamic tendency of hydrogen evolution.Consequently,it presents stable cycle for more than 2400 h at 5 mA cm^(-2),as well as an average Coulombic efficiency of 99.8% at 1 A g^(-1) after 800 cycles in the Zn‖VO_(2) full cell.The interphase engineering strategy zinc anode by organic small molecular brings new possibility towards high-performance aqueous zinc-ion batteries. 展开更多
关键词 Zn anode Organic small molecule Aqueous zinc-ion battery Zinc formate
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Pre-training transformer with dual-branch context content module for table detection in document images
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作者 Yongzhi LI Pengle ZHANG +2 位作者 Meng SUN Jin HUANG Ruhan HE 《虚拟现实与智能硬件(中英文)》 EI 2024年第5期408-420,共13页
Background Document images such as statistical reports and scientific journals are widely used in information technology.Accurate detection of table areas in document images is an essential prerequisite for tasks such... Background Document images such as statistical reports and scientific journals are widely used in information technology.Accurate detection of table areas in document images is an essential prerequisite for tasks such as information extraction.However,because of the diversity in the shapes and sizes of tables,existing table detection methods adapted from general object detection algorithms,have not yet achieved satisfactory results.Incorrect detection results might lead to the loss of critical information.Methods Therefore,we propose a novel end-to-end trainable deep network combined with a self-supervised pretraining transformer for feature extraction to minimize incorrect detections.To better deal with table areas of different shapes and sizes,we added a dualbranch context content attention module(DCCAM)to high-dimensional features to extract context content information,thereby enhancing the network's ability to learn shape features.For feature fusion at different scales,we replaced the original 3×3 convolution with a multilayer residual module,which contains enhanced gradient flow information to improve the feature representation and extraction capability.Results We evaluated our method on public document datasets and compared it with previous methods,which achieved state-of-the-art results in terms of evaluation metrics such as recall and F1-score.https://github.com/Yong Z-Lee/TD-DCCAM. 展开更多
关键词 table detection Document image analysis TRANSFORMER Dilated convolution Deformable convolution Feature fusion
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Unstable evolution of railway slope under the rainfall-vibration joint action
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作者 DONG Haoyu WANG Jiading +2 位作者 ZHANG Dengfei LI Lin XU Yuanjun 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1419-1431,共13页
Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of trains.However,as two major factors affecting the stability of railway slopes,few s... Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of trains.However,as two major factors affecting the stability of railway slopes,few scholars have explored the unstable evolution of railway slopes under the joint action of rainfall-vibration.Based on the model test of sandy soil slope,the unstable evolution process of slope under locomotive vibration,rainfall,and rainfall-vibration joint action conditions was simulated in this paper.By comparing and analyzing the variation trends of soil pressure and water content of slope under these conditions,the change laws of pore pressure under the influence of vibration and rainfall were explored.The main control factors affecting the stability of slope structure under the joint action conditions were further defined.Combined with the slope failure phenomena under these three conditions,the causes of slope instability resulting from each leading factor were clarified.Finally,according to the above conclusions,the unstable evolution of the slope under the rainfall-vibration joint action was determined.The test results show that the unstable evolution process of sandy soil slope,under the rainfall-vibration joint action,can be divided into:rainfall erosion cracking,vibration promotion penetrating,and slope instability sliding three stages.In the process of slope unstable evolution,rainfall and vibration play the roles of inducing and promoting slide respectively.In addition,the deep cracks,which are the premise for the formation of the sliding surface,and the violent irregular fluctuation of soil pressure,which reflects the near penetration of the sliding surface,constitute the instability characteristics of the railway slope together.This paper reveals the unstable evolution of sandy soil slopes under the joint action of rainfall-vibration,hoping to provide the theoretical basis for the early warning and prevention technology of railway slopes. 展开更多
关键词 Rainfall vibration joint action small scale model tests Unstable evolution process Unstable characteristics Inducing sliding and promoting sliding
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Impact of water table on hierarchically nested groundwater flow system
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作者 Jun Zhang Rong-zhe Hou +2 位作者 Kun Yu Jia-qiu Dong Li-he Yin 《Journal of Groundwater Science and Engineering》 2024年第2期119-131,共13页
Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flo... Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flow systems.Moreover,it remains challenging to identify characteristics of water table space variation through limited groundwater observations at the regional scale.Based on two ideal two-dimensional cross-section analytical models,this study presents a simplified approach to preliminarily assess the nonlinear interactions between water table variation and three driving factors:Topography,geol-ogy and climate.Two criteria,C1 and C2,are utilized to address issues at different scales ranging from basin to local:(i)the influence of various factors on water table configuration;and(ii)the influence of water table on groundwater flow pattern.Then,the Ordos Plateau is taken as an example to explore the role of the water table in nested groundwater systems using the provided approach and criterion.The applica-tion of this approach in the Ordos Plateau demonstrates its appropriateness as a practical method for prelim-inarily determining the characteristics of water table configuration and its impact on flow systems.The study explores the mechanism influencing spatial variation in the water table and improves understanding of the interaction between topography,geology,and climate on groundwater flow patterns. 展开更多
关键词 Water table configuration Groundwater flow pattern Analytical models Top boundary condi-tions Ordos Plateau
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基于AFF-Stablenet模型的小样本轴承故障诊断
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作者 郭康 王志刚 徐增丙 《现代制造工程》 CSCD 北大核心 2024年第9期144-151,53,共9页
针对滚动轴承在小样本条件下诊断准确率低和泛化性弱的问题,提出了一种基于注意力特征融合的深度稳定学习(Attention Feature Fusion and Deep Stable Learning,AFF-Stablenet)模型的故障诊断方法。该方法首先使用经验模态分解(Empirica... 针对滚动轴承在小样本条件下诊断准确率低和泛化性弱的问题,提出了一种基于注意力特征融合的深度稳定学习(Attention Feature Fusion and Deep Stable Learning,AFF-Stablenet)模型的故障诊断方法。该方法首先使用经验模态分解(Empirical Mode Decompositim,EMD)将样本分解成多段频率的子信号,求取子信号与原始信号的互相关系数,选择系数较高的前三阶子信号;利用连续小波变换(Continuws Narelet Transorm,CWT)将子信号转换为时频图表示,通过注意力特征融合的方式将这些时频图特征进行融合;最后将融合特征输入到深度稳定学习(Stablenet)模型进行训练与预测。为验证模型的有效性,采用凯斯西储大学轴承数据集进行各组对比试验,都灵理工大学轴承数据集进行验证。实验结果表明,AFF-Stablenet模型在小样本情况下的泛化性和鲁棒性均强于其他对比模型,证明了模型的优越性。 展开更多
关键词 注意特征融合 深度稳定学习 滚动轴承 小样本 故障诊断
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基于MobileNetV3Small-ECA的水稻病害轻量级识别研究 被引量:5
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作者 袁培森 欧阳柳江 +1 位作者 翟肇裕 田永超 《农业机械学报》 EI CAS CSCD 北大核心 2024年第1期253-262,共10页
为实现水稻病害的轻量化识别与检测,使用ECA注意力机制改进MobileNetV3Small模型,并使用共享参数迁移学习对水稻病害进行智能化轻量级识别和检测。在PlantVillage数据集上进行预训练,将预训练得到的共享参数迁移到对水稻病害识别模型上... 为实现水稻病害的轻量化识别与检测,使用ECA注意力机制改进MobileNetV3Small模型,并使用共享参数迁移学习对水稻病害进行智能化轻量级识别和检测。在PlantVillage数据集上进行预训练,将预训练得到的共享参数迁移到对水稻病害识别模型上微调优化。在开源水稻病害数据集上进行试验测试,试验结果表明,在非迁移学习下,识别准确率达到97.47%,在迁移学习下识别准确率达到99.92%,同时参数量减少26.69%。其次,通过Grad-CAM进行可视化,本文方法与其他注意力机制CBAM和SENET相比,ECA模块生成的结果与图像中病斑的位置和颜色更加一致,表明网络可以更好地聚焦水稻病害的特征,并且通过可视化和各水稻病害分析了误分类原因。本文方法实现了水稻病害识别模型的轻量化,使其能够在移动设备等资源受限的场景中部署,达到快速、高效、便携的目的。同时开发了基于Android的水稻病害识别系统,方便于在边缘端进行水稻病害识别分析。 展开更多
关键词 水稻病害识别 迁移学习 高效通道注意力机制 MobileNetV3small 移动端部署
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miRNA对褐飞虱鞘脂质代谢基因表达的影响及沉默NlSPT1和Nl SMase4的small RNA分析
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作者 王妮 施哲逸 +4 位作者 尤元政 张超 周文武 周瀛 祝增荣 《中国农业科学》 CAS CSCD 北大核心 2024年第20期4022-4034,共13页
【背景】鞘脂质是第二大类膜脂,作为信号转导物质参与细胞生长发育、繁殖及凋亡等过程。鞘脂质代谢酶调控鞘脂质代谢以维持生物体内代谢的稳态。【目的】以重要水稻害虫褐飞虱(Nilaparvata lugens)为研究对象,通过RNA干扰(RNA interfere... 【背景】鞘脂质是第二大类膜脂,作为信号转导物质参与细胞生长发育、繁殖及凋亡等过程。鞘脂质代谢酶调控鞘脂质代谢以维持生物体内代谢的稳态。【目的】以重要水稻害虫褐飞虱(Nilaparvata lugens)为研究对象,通过RNA干扰(RNA interference,RNAi)技术检测微小RNA(microRNA,miRNA)生物合成通路核心组分NlAgo1、NlDicer1和NlDrosha沉默后褐飞虱鞘脂质代谢通路相关基因的相对转录水平,结合small RNA测序分析沉默丝氨酸棕榈酰转移酶1(serine palmitoyltransferase 1,SPT1)和鞘磷脂酶4(sphingomyelinase 4,SMase4)基因的差异miRNA,探究miRNA在褐飞虱鞘脂质代谢中的作用,为害虫防治提供新的分子靶标。【方法】利用RNAi技术,分别对羽化后第1天(1 PAE,post adult eclosion)的雌成虫NlAgo1、NlDicer1和NlDrosha进行dsRNA注射,以ds GFP为对照;分别解剖羽化后第5天的卵巢组织,以β-actin作为内参基因,采用实时荧光定量PCR(qRT-PCR)方法检测NlAgo1、NlDicer1和NlDrosha沉默后鞘脂质代谢通路相关基因的表达量变化;根据已有的小RNA文库联合miRNA-靶基因预测软件对可能调控NlSPT1和NlSMase4表达的miRNA进行预测;通过small RNA测序技术对沉默NlSPT1和NlSMase4的差异miRNA进行鉴定和靶基因富集性分析。【结果】与对照组相比,沉默NlAgo1、NlDicer1或NlDrosha显著上调卵巢中NlSPT1和NlSMase4等鞘脂质代谢通路相关基因的表达;靶基因预测结果显示,有6条miRNA能与NlSPT1结合,13条miRNA能与NlSMase4结合;沉默NlSPT1和NlSMase4的差异miRNA的靶基因显著富集在细胞核和蛋白质结合等生物学过程以及内吞作用、内质网加工、MAPK信号通路、TOR信号通路、凋亡、脂质代谢等代谢通路。【结论】NlAgo1、NlDicer1和NlDrosha依赖性的miRNA通过影响鞘脂质代谢相关基因的表达影响鞘脂质代谢。NlSPT1和NlSMase4沉默引起褐飞虱卵巢miRNA表达水平的改变。研究结果可为基于鞘脂质代谢基因为靶标的害虫防治提供理论依据。 展开更多
关键词 褐飞虱 微小RNA 鞘脂质 RNA干扰 small RNA测序
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Stable isotopic composition of otoliths in identification of stock structure of small yellow croaker(Larimichthys polyactis) in China 被引量:5
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作者 WANG Yukun HUANG Jiansheng +2 位作者 TANG Xuexi JIN Xianshi SUN Yao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第6期29-33,共5页
Oxygen and carbon isotope ratios(δ^(18)O and δ^(13)C) in otoliths were used to identify the stock structure of small yellow croaker,Larimichthys polyactis.Otoliths were collected from fish at five locations ac... Oxygen and carbon isotope ratios(δ^(18)O and δ^(13)C) in otoliths were used to identify the stock structure of small yellow croaker,Larimichthys polyactis.Otoliths were collected from fish at five locations across the Yellow Sea and the Bohai Sea representing most of their distributional range and fisheries areas.The significant differences in the isotopic signatures showed that the five locations could be chemically distinguished and clearly separated,indicating stock subdivision.Correlation of δ^(18)O and δ^(13)C values suggested that population of L.polyactis could be divided into the Bohai Sea group,the southern Yellow Sea group and the central Yellow Sea group.Discriminant analysis of δ^(18)O and δ^(13)C values demonstrated a high significant difference with 85.7% classification accuracy.The spatial separation of L.polyactis indicated a complex stock structure across the Yellow Sea and the Bohai Sea.These results indicate that optimal fisheries management may require a comprehensive consideration on the current spatial arrangements.This study has provided further evidence that measurement of the stable isotopes ratios in otolith can be a valuable tool in the delineation of fishery management units. 展开更多
关键词 small yellow croaker OTOLITH stable isotope chemistry stock structure
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Small bowel capsule endoscopy in patients with cardiac pacemakers and implantable cardioverter defibrillators:Outcome analysis using telemetry review 被引量:6
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作者 Justin R Cuschieri Mohammed N Osman +2 位作者 Richard CK Wong Amitabh Chak Gerard A Isenberg 《World Journal of Gastrointestinal Endoscopy》 CAS 2012年第3期87-93,共7页
AIM:To determine if there were any interactions between cardiac devices and small bowel capsules secondary to electromagnetic interference (EMI) in patients who have undergone small bowel capsule endoscopy (SBCE).METH... AIM:To determine if there were any interactions between cardiac devices and small bowel capsules secondary to electromagnetic interference (EMI) in patients who have undergone small bowel capsule endoscopy (SBCE).METHODS:Authors conducted a chart review of 20 patients with a cardiac pacemaker (CP) or implantable cardioverter defibrillator (ICD) who underwent continuous electrocardiographic monitoring during their SBCE from 2003-2008.authors searched for unexplained electrocardiogram (ECG) findings,changes in CP andICD set parameters,any abnormality in transmitted capsule data,and adverse clinical events.RESULTS:There were no adverse events or hemodynamically significant arrhythmias reported.CP and ICD set parameters were preserved.The majority of ECG abnormalities were also found in pre-or post-SBCE ECG tracings and the CP behavior during arrhythmias appeared appropriate.Two patients seemed to have episodes of undersensing by the CP.However,similar findings were documented in ECGs taken outside the time frame of the SBCE.One patient was observed to have a low signal encountered from the capsule resulting in lack of localization,but no images were lost.CONCLUSION:Capsule-induced EMI remains a possibility but is unlikely to be clinically important.CPinduced interference of SBCE is also possible,but is infrequent and does not result in loss of images transmitted by the capsule. 展开更多
关键词 small bowel capsule endoscopy Cardiac PACEMAKERS Implantable cardioverter DEFIBRILLATORS Electromagnetic interference TELEMETRY REVIEW
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