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基于Batch Normalization的UNet视网膜血管分割算法
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作者 董恒 黄香平 +2 位作者 傅诏午 邹梓秀 林涌 《洛阳师范学院学报》 2024年第5期33-37,共5页
视网膜血管的提取可以通过卷积神经网络学习的方法,但这种方法容易受到初始图像质量的影响,存在网络学习速度慢、效率低的问题.针对这一问题,提出了一种融合Batch Normalization和UNet卷积神经网络的视网膜血管分割算法.以视网膜图像的... 视网膜血管的提取可以通过卷积神经网络学习的方法,但这种方法容易受到初始图像质量的影响,存在网络学习速度慢、效率低的问题.针对这一问题,提出了一种融合Batch Normalization和UNet卷积神经网络的视网膜血管分割算法.以视网膜图像的三原色通道作为网络的输入数据,然后利用融合批归一化的UNet卷积神经网络对分割模型进行训练,进一步优化网络效率.经过测试和验证,结果表明,在DRIVE公开数据集上,该方法能够更好地提取周围血管结构,灵敏度、准确度、特异性和曲线下面积均较好. 展开更多
关键词 血管分割 视网膜图像 UNet 归一化
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Selection and Validation of Reference Genes for Normalization of RT-qPCR Analysis in Developing or Abiotic-Stressed Tissues of Loquat (Eriobotrya japonica) 被引量:1
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作者 Shoukai Lin Shichang Xu +6 位作者 Liyan Huang Fuxiang Qiu Yihong Zheng Qionghao Liu Shiwei Ma Bisha Wu Jincheng Wu 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第4期1185-1201,共17页
Loquat(Eriobotrya japonica Lindl.)is a subtropical evergreen fruit tree that produces fruits with abundant nutrients and medicinal components.Confirming suitable reference genes for a set of loquat samples before qRT-... Loquat(Eriobotrya japonica Lindl.)is a subtropical evergreen fruit tree that produces fruits with abundant nutrients and medicinal components.Confirming suitable reference genes for a set of loquat samples before qRT-PCR experiments is essential for the accurate quantification of gene expression.In this study,eight candidate reference genes were selected from our previously published RNA-seq data,and primers for each candidate reference gene were designed and evaluated.The Cq values of the candidate reference genes were calculated by RT-qPCR in 31 different loquat samples,including 12 subgroups of developing or abiotic-stressed tissues.Different combinations of stable reference genes were screened according to a comprehensive rank,which was synthesized from the results of four algorithms,including the geNorm,NormFinder,BestKeeper andΔCt methods.The screened reference genes were verified by normalizing EjLGA1 in each subgroup.The obtained suitable combinations of reference genes for accurate normalization were GAPDH,EF1αand ACT for floral development;GAPDH,UBCE and ACT for fruit setting;EF1α,GAPDH and eIF2B for fruit ripening;ACT,EF1αand UBCE for leaves under heat stress;eIF2B,UBCE and EF1αfor leaves under freezing stress;EF1α,TUA and UBCE for leaves under salt stress;ACT,EF1αand eIF2B for immature pulp under freezing stress;ACT,UBCE and eIF2B for immature seeds under freezing stress;EF1α,eIF2B and UBCE for both immature pulp and seeds under freezing stress;UBCE,TUB and TUA for red-fleshed fruits under cold-storage stress;eIF2B,RPS3 and TUB for white-fleshed fruits under coldstorage stress;and eIF2B,UBCE and RPS3 for both red-and white-fleshed fruits under cold-storage stress.This study obtained different combinations of stable reference genes for accurate normalization in twelve subgroups of developing or abiotic-stressed tissues in loquat.To our knowledge,this is the first report to obtain stable reference genes for normalizing gene expression of abiotic-stressed tissues in E.japonica.The use of the three most stable reference genes could increase the reliability of future quantification experiments. 展开更多
关键词 LOQUAT Eriobotrya japonica reference genes qRT-PCR gene expression normalization developing tissues abiotic-stressed tissues
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Clinical manifestations,diagnosis and long-term prognosis of adult autoimmune enteropathy:Experience from Peking Union Medical College Hospital 被引量:1
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作者 Mu-Han Li Ge-Chong Ruan +9 位作者 Wei-Xun Zhou Xiao-Qing Li Sheng-Yu Zhang Yang Chen Xiao-Yin Bai Hong Yang Yu-Jie Zhang Peng-Yu Zhao Ji Li Jing-Nan Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第19期2523-2537,共15页
BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis an... BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis and prognosis.METHODS We retrospectively analyzed the clinical,endoscopic and histopathological characteristics and prognoses of 16 adult AIE patients in our tertiary medical center between 2011 and 2023,whose diagnosis was based on the 2007 diagnostic criteria.RESULTS Diarrhea in AIE patients was characterized by secretory diarrhea.The common endoscopic manifestations were edema,villous blunting and mucosal hyperemia in the duodenum and ileum.Villous blunting(100%),deep crypt lymphocytic infiltration(67%),apoptotic bodies(50%),and mild intraepithelial lymphocytosis(69%)were observed in the duodenal biopsies.Moreover,there were other remarkable abnormalities,including reduced or absent goblet cells(duodenum 94%,ileum 62%),reduced or absent Paneth cells(duodenum 94%,ileum 69%)and neutrophil infiltration(duodenum 100%,ileum 69%).Our patients also fulfilled the 2018 diagnostic criteria but did not match the 2022 diagnostic criteria due to undetectable anti-enterocyte antibodies.All patients received glucocorticoid therapy as the initial medication,of which 14/16 patients achieved a clinical response in 5(IQR:3-20)days.Immunosuppressants were administered to 9 patients with indications of steroid dependence(6/9),steroid refractory status(2/9),or intensified maintenance medication(1/9).During the median of 20.5 months of followup,2 patients died from multiple organ failure,and 1 was diagnosed with non-Hodgkin’s lymphoma.The cumulative relapse-free survival rates were 62.5%,55.6%and 37.0%at 6 months,12 months and 48 months,respectively.CONCLUSION Certain histopathological findings,including a decrease or disappearance of goblet and Paneth cells in intestinal biopsies,might be potential diagnostic criteria for adult AIE.The long-term prognosis is still unsatisfactory despite corticosteroid and immunosuppressant medications,which highlights the need for early diagnosis and novel medications. 展开更多
关键词 Autoimmune enteropathy Clinical manifestations Diagnostic criteria Pathological features long-term prognosis
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Supervised Feature Learning for Offline Writer Identification Using VLAD and Double Power Normalization
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作者 Dawei Liang Meng Wu Yan Hu 《Computers, Materials & Continua》 SCIE EI 2023年第7期279-293,共15页
As an indispensable part of identity authentication,offline writer identification plays a notable role in biology,forensics,and historical document analysis.However,identifying handwriting efficiently,stably,and quick... As an indispensable part of identity authentication,offline writer identification plays a notable role in biology,forensics,and historical document analysis.However,identifying handwriting efficiently,stably,and quickly is still challenging due to the method of extracting and processing handwriting features.In this paper,we propose an efficient system to identify writers through handwritten images,which integrates local and global features from similar handwritten images.The local features are modeled by effective aggregate processing,and global features are extracted through transfer learning.Specifically,the proposed system employs a pre-trained Residual Network to mine the relationship between large image sets and specific handwritten images,while the vector of locally aggregated descriptors with double power normalization is employed in aggregating local and global features.Moreover,handwritten image segmentation,preprocessing,enhancement,optimization of neural network architecture,and normalization for local and global features are exploited,significantly improving system performance.The proposed system is evaluated on Computer Vision Lab(CVL)datasets and the International Conference on Document Analysis and Recognition(ICDAR)2013 datasets.The results show that it represents good generalizability and achieves state-of-the-art performance.Furthermore,the system performs better when training complete handwriting patches with the normalization method.The experimental result indicates that it’s significant to segment handwriting reasonably while dealing with handwriting overlap,which reduces visual burstiness. 展开更多
关键词 Writer identification power normalization vector of locally aggregated descriptors feature extraction
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Relationship between body surface area and ALT normalization after long-term lamivudine treatment 被引量:1
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作者 Makoto Nakamuta Shusuke Morizono +14 位作者 Yuichi Tanabe Eiji Kajiwara Junya Shimono Akihide Masumoto Toshihiro Maruyama Norihiro Furusyo Hideyuki Nomura Hironori Sakai Kazuhiro Takahashi Koichi Azuma Shinji Shimoda Kazuhiro Kotoh Munechika Enjoji Jun Hayashi Kyushu University liver Disease Study Group 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第44期6948-6953,共6页
AIM: To further evaluate the relationship between BSA and the effects of lamivudine in a greater number of cases and over a longer period of observation than in our previous evaluation. METHODS: We evaluated 249 pat... AIM: To further evaluate the relationship between BSA and the effects of lamivudine in a greater number of cases and over a longer period of observation than in our previous evaluation. METHODS: We evaluated 249 patients with chronic hepatitis B. The effects of treatment for one year (n = 249), two years (n = 147), and three years (n = 72) were evaluated from the levels of serum ALT and HBVoDNA, as biological and virological effects (undetectable levels by PCR), respectively. Moreover, several variables that could influence the response to treatment, including ALT, albumin, bilirubin, platelet counts, BSA, HBVoDNA, and HBeAg were analyzed. RESULTS: For 1-year treatment, multivariate analysis revealed that BSA (P = 0.0002) was the only factor for the biological effect, and that ALT (P = 0.0017), HBV- DNA (P = 0.0004), and HBeAg (P = 0.0021) were independent factors for the virological effect. For 2-year treatment, multivariate analysis again showed that BSA (P = 0.0147) was the only factor for the biological effect, and that ALT (P = 0.0192) and HBeAg (P = 0.0428) were independent factors for the virological effect. For 3-year treatment, multivariate analysis, however, could not reveal BSA (P = 0.0730) as a factor for the normalization of ALT levels. CONCLUSION: BSA is a significant predictor for the normalizing the effect of lamivudine therapy on ALT for an initial 2-year period, suggesting that lamivudine dosage should be based on the individual BSA. 展开更多
关键词 LAMIVUDINE Hepatitis B virus Body surface area DOSE long-term treatment
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Robust Radiometric Normalization of the near Equatorial Satellite Images Using Feature Extraction and Remote Sensing Analysis
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作者 Hayder Dibs Shattri Mansor +1 位作者 Noordin Ahmad Nadhir Al-Ansari 《Engineering(科研)》 CAS 2023年第2期75-89,共15页
Relative radiometric normalization (RRN) minimizes radiometric differences among images caused by inconsistencies of acquisition conditions rather than changes in surface. Scale invariant feature transform (SIFT) has ... Relative radiometric normalization (RRN) minimizes radiometric differences among images caused by inconsistencies of acquisition conditions rather than changes in surface. Scale invariant feature transform (SIFT) has the ability to automatically extract control points (CPs) and is commonly used for remote sensing images. However, its results are mostly inaccurate and sometimes contain incorrect matching caused by generating a small number of false CP pairs. These CP pairs have high false alarm matching. This paper presents a modified method to improve the performance of SIFT CPs matching by applying sum of absolute difference (SAD) in a different manner for the new optical satellite generation called near-equatorial orbit satellite and multi-sensor images. The proposed method, which has a significantly high rate of correct matches, improves CP matching. The data in this study were obtained from the RazakSAT satellite a new near equatorial satellite system. The proposed method involves six steps: 1) data reduction, 2) applying the SIFT to automatically extract CPs, 3) refining CPs matching by using SAD algorithm with empirical threshold, and 4) calculation of true CPs intensity values over all image’ bands, 5) preforming a linear regression model between the intensity values of CPs locate in reverence and sensed image’ bands, 6) Relative radiometric normalization conducting using regression transformation functions. Different thresholds have experimentally tested and used in conducting this study (50 and 70), by followed the proposed method, and it removed the false extracted SIFT CPs to be from 775, 1125, 883, 804, 883 and 681 false pairs to 342, 424, 547, 706, 547, and 469 corrected and matched pairs, respectively. 展开更多
关键词 Relative Radiometric normalization Scale Invariant Feature Transform Automatically Extraction Control Points Sum of Absolute Difference
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The influence of lipid-extraction on theδ^(13)C of mesopelagic and demersal fish in the South China Sea:modification and application of lipid normalization models
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作者 Linyu Wang Fuqiang Wang +1 位作者 Zuozhi Chen Ying Wu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第1期35-43,共9页
Mesopelagic fish,the most important daily vertically migrating community in the oceans,are characterized by high lipid content which may obscure the interpretation of stable isotopes analysis.Demersal fish,which are i... Mesopelagic fish,the most important daily vertically migrating community in the oceans,are characterized by high lipid content which may obscure the interpretation of stable isotopes analysis.Demersal fish,which are important consumers in the food web dominated by mesopelagic fish,also have a high lipid content.Here we collected 127 fish samples from the South China Sea and evaluated the effect of lipid contents on△δ^(13)C of mesopelagic and demersal fish.In lipid-extracted mesopelagic fish,the C/N content ratio(<5.5)shows a clear correlation withΔδ^(13)C(the offset of bulk and lipid-extractedδ^(13)C values),especially in non-migratory and semi-migratory species;these values were less correlation in demersal fish.Based on our results,we suggest that mesopelagic and demersal fish in different regions of the South China Sea should be studied separately using appropriate correction models and less fit for the traditional model.Moreover,the C/N content ratio should be used cautiously for establishing the lipid normalization model,especially for the fish in migratory mesopelagic fish and demersal fish.Our results also reveal that mesopelagic fish across nearby regions could be analyzed together.The new models described here can be applied in future studies of mesopelagic and demersal fish in the South China Sea. 展开更多
关键词 mesopelagic fish demersal fish lipid normalization model C/N content ratio lipid content δ13C South China Sea
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Long-Term Performance and Microstructural Characterization of Dam Concrete in the Three Gorges Project
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作者 Chen Lyu Cheng Yu +3 位作者 Chao Lu Li Pan Wenwei Li Jiaping Liu 《Engineering》 SCIE EI CAS CSCD 2024年第2期237-262,共26页
This study investigates the long-term performance of laboratory dam concrete in different curing environments over ten years and the microstructure of 17-year-old laboratory concrete and actual concrete cores drilled ... This study investigates the long-term performance of laboratory dam concrete in different curing environments over ten years and the microstructure of 17-year-old laboratory concrete and actual concrete cores drilled from the Three Gorges Dam.The mechanical properties of the laboratory dam concrete,whether cured in natural or standard environments,continued to improve over time.Furthermore,the laboratory dam concrete exhibited good resistance to diffusion and a refined microstructure after 17 years.However,curing and long-term exposure to the local natural environment reduced the frost resistance.Microstructural analyses of the laboratory concrete samples demonstrated that moderate-heat cement and fine fly ash(FA)particles were almost fully hydrated to form compact micro structures consisting of large quantities of homogeneous calcium(alumino)silicate hydrate(C-(A)-S-H)gels and a few crystals.No obvious interfacial transition zones were observed in the microstructure owing to the longterm pozzolanic reaction.This dense and homogenous microstructure was the crucial reason for the excellent long-term performance of the dam concrete.A high FA volume also played a significant role in the microstructural densification and performance growth of dam concrete at a later age.The concrete drilled from the dam surface exhibited a loose microstructure with higher microporosity,indicating that concrete directly exposed to the actual service environment suffered degradation caused by water and wind attacks.In this study,both macro-performance and microstructural analyses revealed that the application of moderate-heat cement and FA resulted in a dense and homogenous microstructure,which ensured the excellent long-term performance of concrete from the Three Gorges Dam after 17 years.Long-term exposure to an actual service environment may lead to microstructural degradation of the concrete surface.Therefore,the retained long-term dam concrete samples need to be further researched to better understand its microstructural evolution and development of its properties. 展开更多
关键词 Three Gorges Dam long-term performance Microstructural analysis Moderate-heat cement Fly ash
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Soil bacterial and fungal communities resilience to long-term nitrogen addition in subtropical forests in China
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作者 Xinlei Fu Yunze Dai +3 位作者 Jun Cui Pengfei Deng Wei Fan Xiaoniu Xu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期95-108,共14页
Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have no... Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in China.The four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence networks.Nutrient-treated soils were more acidic and had higher levels of dissolved organic carbon than controls.There were no significant differences in microbial diversity and community composition across treatments.The addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,Chaetomium,and Aureobasidium).Low N addition increased microbiome network connectivity.Three rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased nutrients.The results indicate that the overall composition of microbial communities was stable but not static to long-term N addition.Our findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition. 展开更多
关键词 long-term nitrogen addition Old-growth subtropical forest METAGENOMICS Beneficial microorganisms Co-occurrence network
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Long-term thinning decreases the contribution of heterotrophic respiration to soil respiration in subalpine plantations
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作者 Longfei Chen Zhibin He +7 位作者 Wenzhi Zhao Xi Zhu Qin Shen Mingdan Song Zhengpeng Li Junqia Kong Shuping Yang Yuan Gao 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期189-204,共16页
Interest in the dynamics of soil respiration(R_(S))in subalpine forest ecosystems is increasing due to their high soil carbon density and potential sensitivity to environmental changes.However,as a principal silvicult... Interest in the dynamics of soil respiration(R_(S))in subalpine forest ecosystems is increasing due to their high soil carbon density and potential sensitivity to environmental changes.However,as a principal silvicultural practice,the long-term impacts of thinning on R_(S) and its heterotrophic and autotrophic respiration components(R_(h) and Ra,respectively)in subalpine plantations are poorly understood,espe-cially in winter.A 3-year field observation was carried out with consideration of winter CO_(2) efflux in middle-aged sub-alpine spruce plantations in northwestern China.A trench-ing method was used to explore the long-term impacts of thinning on Rs,Rn and R_(a).Seventeen years after thinning,mean annual Rs,Rn and R_(a) increased,while the contribu-tion of R_(h) to R_(s) decreased with thinning intensity.Thinning significantly decreased winter R,because of the reduction in R_(n) but had no significant effect on Ra.The temperature sensitivity(Q_(10))of R_(h) and R_(a) also increased with thinning intensity,with lower Q_(10) values for R_(h)(2.1-2.6)than for Ra(2.4-2.8).The results revealed the explanatory variables and pathways related to R_(n) and R_(a) dynamics.Thinning increased soil moisture and nitrate nitrogen(NO_(3)^(-)-N),and the enhanced nitrogen and water availability promoted R_(h) and R_(a) by improving fine root biomass and microbial activity.Our results highlight the positive roles of NO_(3)^(-)-N in stimulating R_(s) components following long-term thinning.Therefore,applications of nitrogen fertilizer are not recommended while thinning subalpine spruce plantations from the perspective of reducing soil CO_(2) emissions.The increased Q_(10) values of R_(s) components indicate that a large increase in soil CO_(2) emissions would be expected following thinning because of more pronounced climate warming in alpineregions. 展开更多
关键词 Heterotrophic respiration Autotrophic respiration long-term thinning impacts Cold seasons Subalpine plantations Temperature sensitivity
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Extraction of Acoustic Normal Mode Depth Functions Using Range-Difference Method with Vertical Linear Array Data
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作者 GAO Siyu LI Weilu +2 位作者 ZHANG Yinquan LI Xiaolei WANG Ning 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期871-882,共12页
Data-derived normal mode extraction is an effective method for extracting normal mode depth functions in the absence of marine environmental data.However,when the corresponding singular vectors become nonunique when t... Data-derived normal mode extraction is an effective method for extracting normal mode depth functions in the absence of marine environmental data.However,when the corresponding singular vectors become nonunique when two or more singular values obtained from the cross-spectral density matrix diagonalization are nearly equal,this results in unsatisfactory extraction outcomes for the normal mode depth functions.To address this issue,we introduced in this paper a range-difference singular value decomposition method for the extraction of normal mode depth functions.We performed the mode extraction by conducting singular value decomposition on the individual frequency components of the signal's cross-spectral density matrix.This was achieved by using pressure and its range-difference matrices constructed from vertical line array data.The proposed method was validated using simulated data.In addition,modes were successfully extracted from ambient noise. 展开更多
关键词 range difference depth function extraction normal mode
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Schur Forms and Normal-Nilpotent Decompositions
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作者 LI Zhen 《应用数学和力学》 CSCD 北大核心 2024年第9期1200-1211,共12页
Real and complex Schur forms have been receiving increasing attention from the fluid mechanics community recently,especially related to vortices and turbulence.Several decompositions of the velocity gradient tensor,su... Real and complex Schur forms have been receiving increasing attention from the fluid mechanics community recently,especially related to vortices and turbulence.Several decompositions of the velocity gradient tensor,such as the triple decomposition of motion(TDM)and normal-nilpotent decomposition(NND),have been proposed to analyze the local motions of fluid elements.However,due to the existence of different types and non-uniqueness of Schur forms,as well as various possible definitions of NNDs,confusion has spread widely and is harming the research.This work aims to clean up this confusion.To this end,the complex and real Schur forms are derived constructively from the very basics,with special consideration for their non-uniqueness.Conditions of uniqueness are proposed.After a general discussion of normality and nilpotency,a complex NND and several real NNDs as well as normal-nonnormal decompositions are constructed,with a brief comparison of complex and real decompositions.Based on that,several confusing points are clarified,such as the distinction between NND and TDM,and the intrinsic gap between complex and real NNDs.Besides,the author proposes to extend the real block Schur form and its corresponding NNDs for the complex eigenvalue case to the real eigenvalue case.But their justification is left to further investigations. 展开更多
关键词 Schur form normal matrix nilpotent matrix tensor decomposition vortex identification
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Shear mechanical properties and frictional sliding responses of rough joint surfaces under dynamic normal displacement conditions
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作者 ZHU Qiang YIN Qian +9 位作者 TAO Zhi-gang HE Man-chao ZHENG Bo-wen JING Hong-wen REN Shu-lin ZHANG Qiang MENG Bo BAI Dong-feng WU Sai-sai WU Jiang-yu 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2393-2410,共18页
A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating... A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating geological disasters.This study conducted shear experiments on rough rock joints under displacement-controlled dynamic normal loads,investigating the shear behaviors of joints across varying initial normal loads,normal loading frequencies,and normal loading amplitudes.Experimental results showed that the peak/valley shear force values increased with initial normal loads and normal loading frequencies but showed an initial increase followed by a decrease with normal loading amplitudes.Dynamic normal loading can either increase or decrease shear strength,while this study demonstrates that higher frequencies lead to enhanced friction.Increased initial normal loading and normal loading frequency result in a gradual decrease in joint roughness coefficient(JRC)values of joint surfaces after shearing.Positive correlations existed between frictional energy dissipation and peak shear forces,while post-shear joint surface roughness exhibited a negative correlation with peak shear forces through linear regression analysis.This study contributes to a better understanding of the sliding responses and shear mechanical characteristics of rock joints under dynamic disturbances. 展开更多
关键词 dynamic normal displacement shear strength variations phase lag phenomenon STICK-SLIP
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A novel mitigation measure for normal fault-induced deformations on pile-raft systems
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作者 Mohammadreza Jahanshahi Nowkandeh Mehdi Ashtiani 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期15-33,共19页
Evidence from recent earthquakes has shown destructive consequences of fault-induced permanent ground movement on structures.Such observations have increased the demand for improvements in the design of structures tha... Evidence from recent earthquakes has shown destructive consequences of fault-induced permanent ground movement on structures.Such observations have increased the demand for improvements in the design of structures that are dramatically vulnerable to surface fault ruptures.In this study a novel connection between the raft and the piles is proposed to mitigate the hazards associated with a normal fault on pile-raft systems by means of 3D finite element(FE)modeling.Before embarking on the parametric study,the strain-softening constitutive law used for numerical modeling of the sand has been validated against centrifuge test results.The exact location of the fix-head and unconnected pile-raft systems relative to the outcropping fault rupture in the free-field is parametrically investigated,revealing different failure mechanisms.The performance of the proposed connection for protecting the pile-raft system against normal fault-induced deformations is assessed by comparing the geotechnical and structural responses of both types of foundation.The results indicate that the pocket connection can relatively reduce the cap rotation and horizontal and vertical displacements of the raft in most scenarios.The proposed connection decreases the bending moment response of the piles to their bending moment capacity,verging on a fault offset of 0.6 m at bedrock. 展开更多
关键词 normal fault rupture failure mechanism pile-raft system pocket connection finite element modeling
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Depth-Guided Vision Transformer With Normalizing Flows for Monocular 3D Object Detection
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作者 Cong Pan Junran Peng Zhaoxiang Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期673-689,共17页
Monocular 3D object detection is challenging due to the lack of accurate depth information.Some methods estimate the pixel-wise depth maps from off-the-shelf depth estimators and then use them as an additional input t... Monocular 3D object detection is challenging due to the lack of accurate depth information.Some methods estimate the pixel-wise depth maps from off-the-shelf depth estimators and then use them as an additional input to augment the RGB images.Depth-based methods attempt to convert estimated depth maps to pseudo-LiDAR and then use LiDAR-based object detectors or focus on the perspective of image and depth fusion learning.However,they demonstrate limited performance and efficiency as a result of depth inaccuracy and complex fusion mode with convolutions.Different from these approaches,our proposed depth-guided vision transformer with a normalizing flows(NF-DVT)network uses normalizing flows to build priors in depth maps to achieve more accurate depth information.Then we develop a novel Swin-Transformer-based backbone with a fusion module to process RGB image patches and depth map patches with two separate branches and fuse them using cross-attention to exchange information with each other.Furthermore,with the help of pixel-wise relative depth values in depth maps,we develop new relative position embeddings in the cross-attention mechanism to capture more accurate sequence ordering of input tokens.Our method is the first Swin-Transformer-based backbone architecture for monocular 3D object detection.The experimental results on the KITTI and the challenging Waymo Open datasets show the effectiveness of our proposed method and superior performance over previous counterparts. 展开更多
关键词 Monocular 3D object detection normalizing flows Swin Transformer
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Neuroimaging in atypical normal tension glaucoma:debating routine implementation in the absence of classic neurological findings
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作者 Umay Güvenç Gülizar Demirok +1 位作者 Güner Üney Selma Uzman 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期509-517,共9页
●AIM:To assess the necessity of neuroimaging in patients with neurological or atypical findings of normal tension glaucoma(NTG)who do not exhibit typical glaucoma manifestations.●METHODS:A retrospective analysis was... ●AIM:To assess the necessity of neuroimaging in patients with neurological or atypical findings of normal tension glaucoma(NTG)who do not exhibit typical glaucoma manifestations.●METHODS:A retrospective analysis was conducted on 90 atypical NTG patients who underwent cranial magnetic resonance imaging(MRI)due to atypical symptoms.The demographic characteristics,clinical parameters,and radiological findings were recorded.●RESULTS:Among the patients,66.7%had abnormal radiology results,with the most common findings being gliosis(34.4%),sequelae of cerebrovascular events and vascular malformations(14.4%),and benign intracranial mass lesions(11%).Non-glaucomatous visual field defects were more frequently observed in patients with abnormal neuroimaging results.However,there were no significant differences in intraocular pressure,optic disc parameters,retinal nerve fiber layer thickness,and visual field indices between patients with normal and abnormal radiological results.The mean age of the patients was 58.74y.Interestingly,there was a significant age difference,with the abnormal radiology group having a higher median age(P=0.021).●CONCLUSION:The study highlights the importance of cranial imaging in older NTG patients to detect underlying pathologies and prevent misdiagnosis.It suggests that neuroimaging may be warranted in NTG patients with atypical visual field defects incompatible with glaucoma.However,routine neuroimaging in all NTG patients without classic neurological signs may not be necessary. 展开更多
关键词 normal tension glaucoma NEUROIMAGING atypical visual field defects
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Optimism,Social Support,and Caregiving Burden among the Long-Term Caregivers:The Mediating Effect of Psychological Resilience
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作者 Chia-Hui Hou Po-Lin Chen 《International Journal of Mental Health Promotion》 2024年第9期697-708,共12页
Background:As the elderly population grows,the demand for long-term care services is increasing.Despite significant investments in care quality and workforce training,long-term care workers often face challenges such ... Background:As the elderly population grows,the demand for long-term care services is increasing.Despite significant investments in care quality and workforce training,long-term care workers often face challenges such as work fatigue,heavy workloads,and inadequate support.These issues can impact job satisfaction,mental health,and care quality,leading to staff turnover.This study examines how optimism,social support,and psychological resilience relate to caregiving burden,aiming to understand their effects on caregivers’well-being and performance to enhance the quality of long-term care services.Methods:The participants were 542 long-term care workers.Descriptive statistics,t-tests,one-way ANOVA,and hierarchical regression were used for data analysis.Results:(1)Optimism and social support were significantly and positively correlated with psychological resilience and significantly and negatively associated with caregiving burden.(2)Regarding differences in optimism,social support,psychological resilience,and caregiving burden among long-term care workers,females scored significantly higher than males in“social support;”married workers scored significantly higher than unmarried workers in“optimism,”“social support,”and“psychological resilience”;workers aged 45–65 scored significantly higher than those aged 25–45 in“optimism”;workers aged 25–45 scored significantly higher than those aged 45–65 in“caregiving burden”;social workers scored significantly higher than nursing staff in“optimism.”(3)Psychological resilience partially mediated the relationship between social support and caregiving burden concerning explanatory and predictive power.Conclusions:These findings suggest that optimism,social support,and psychological resilience are essential factors in reducing the caregiving burden among long-term care workers.The study highlights the importance of promoting psychological resilience and providing social support to alleviate the burden of caregiving. 展开更多
关键词 long-term care OPTIMISM social support psychological resilience caregiving burden
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Development of a new Cox model for predicting long-term survival in hepatitis cirrhosis patients underwent transjugular intrahepatic portosystemic shunts
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作者 Yi-Fan Lv Bing Zhu +8 位作者 Ming-Ming Meng Yi-Fan Wu Cheng-Bin Dong Yu Zhang Bo-Wen Liu Shao-Li You Sa Lv Yong-Ping Yang Fu-Quan Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期491-502,共12页
BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)placement is a procedure that can effectively treat complications of portal hypertension,such as variceal bleeding and refractory ascites.However,there hav... BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)placement is a procedure that can effectively treat complications of portal hypertension,such as variceal bleeding and refractory ascites.However,there have been no specific studies on predicting long-term survival after TIPS placement.AIM To establish a model to predict long-term survival in patients with hepatitis cirrhosis after TIPS.METHODS A retrospective analysis was conducted on a cohort of 224 patients who un-derwent TIPS implantation.Through univariate and multivariate Cox regression analyses,various factors were examined for their ability to predict survival at 6 years after TIPS.Consequently,a composite score was formulated,encompassing the indication,shunt reasonability,portal venous pressure gradient(PPG)after TIPS,percentage decrease in portal venous pressure(PVP),indocyanine green retention rate at 15 min(ICGR15)and total bilirubin(Tbil)level.Furthermore,the performance of the newly developed Cox(NDC)model was evaluated in an in-ternal validation cohort and compared with that of a series of existing models.RESULTS The indication(variceal bleeding or ascites),shunt reasonability(reasonable or unreasonable),ICGR15,post-operative PPG,percentage of PVP decrease and Tbil were found to be independent factors affecting long-term survival after TIPS placement.The NDC model incorporated these parameters and successfully identified patients at high risk,exhibiting a notably elevated mortality rate following the TIPS procedure,as observed in both the training and validation cohorts.Additionally,in terms of predicting the long-term survival rate,the performance of the NDC model was significantly better than that of the other four models[Child-Pugh,model for end-stage liver disease(MELD),MELD-sodium and the Freiburg index of post-TIPS survival].CONCLUSION The NDC model can accurately predict long-term survival after the TIPS procedure in patients with hepatitis cirrhosis,help identify high-risk patients and guide follow-up management after TIPS implantation. 展开更多
关键词 Transjugular intrahepatic portosystemic shunt long-term survival Predictive model
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Long-Term Mortality of Children with Congenital Heart Disease Admitted to the Departmental University Hospital of Borgou/Alibori from 2011 to 2022
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作者 Serge Hugues Mahougnon Dohou Nicolas Hamondji Amegan +3 位作者 Ahmad Ibrahim Gérard Médétinmè Kpanidja Chabi Olaniran Alphonse Biaou Houétondji Léopold Codjo 《World Journal of Cardiovascular Diseases》 CAS 2024年第3期166-186,共21页
Background: Congenital heart disease is a public health issue due to its incidence and mortality rate. The aim of this study was to investigate the long-term mortality of children with congenital heart disease admitte... Background: Congenital heart disease is a public health issue due to its incidence and mortality rate. The aim of this study was to investigate the long-term mortality of children with congenital heart disease admitted to the Departmental University Hospital of Borgou/Alibori (CHUD-B/A) from 2011 to 2022. Methods: This descriptive longitudinal study with analytical aims covered 11 years (April 1, 2011 to December 31, 2022). It consisted of a review of the records of children under 15 years of age with echocardiographically confirmed congenital heart disease. This was followed by an interview with the parents to assess the children’s current condition. Data were entered using Kobocollect software and analyzed using R Studio 4.2.2. software. Results: A total of 143 complete files were retained. The median age at diagnosis was 14 months (IIQ: Q1 = 4;Q3 = 60) with a range of 2 days and 175 months, and the sex-ratio (M/F) was 0.96. Left-to-right shunts were the most frequent cardiopathy group (62.9%). Only 35 children (24.5%) benefited from restorative treatment. The mortality rate was 31.5%. Median survival under the maximum bias assumption was 114 months and 216 months under the assumption of minimum bias. Survival was significantly better in children with right-to-left shunts (p = 0.0049) under the assumption of minimum bias. The death risk factors were: age at diagnosis less than 12 months (aHR = 7.58;95% CI = 3.36 - 17.24;p Conclusion: The long-term mortality of congenital heart disease is high and favoured by the absence of restorative treatment. Local correction of congenital heart disease and medical follow-up will help to reduce this mortality. 展开更多
关键词 Congenital Heart Disease long-term MORTALITY Parakou Risk Factors
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Long-term performance of recycled asphalt mixtures containing high RAP and RAS
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作者 Jiangmiao Yu Zengyao Lin +3 位作者 Guilian Zou Huayang Yu Zhen Leng Yuan Zhang 《Journal of Road Engineering》 2024年第1期36-53,共18页
The application of reclaimed asphalt pavement(RAP)and reclaimed asphalt shingles(RAS)on asphalt pavement can reduce the asphalt paving cost,conserve energy and protect the environment.However,the use of high contents ... The application of reclaimed asphalt pavement(RAP)and reclaimed asphalt shingles(RAS)on asphalt pavement can reduce the asphalt paving cost,conserve energy and protect the environment.However,the use of high contents of RAP and RAS in asphalt pavement may lead to durability issues,especially the fatigue cracking and thermal cracking.It is necessary to conduct a series of analyses on asphalt mixtures containing high RAP and RAS,and seek methods to enhance their long-term performance.This paper provides a comprehensive over-view of the long-term performance of recycled asphalt mixtures containing high contents of RAP and RAS.The findings in this research show that rutting resistance of high recycled asphalt mixtures is not a concern,whereas their resistance to fatigue and thermal cracking is not conclusive.Recycling agents can be used to improve the thermal cracking resistance of high recycled asphalt mixtures.An optimum decision on recycling agents will improve the durability properties of high recycled asphalt mixtures.It is recommended that to use a balanced mixture design approach with testing of the blended asphalt binders will provide better understanding of long-term performance of recycled asphalt mixtures containing high RAP and RAS. 展开更多
关键词 Recycled asphalt mixture Recycling agents long-term performance CRACKING
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