期刊文献+
共找到7,376篇文章
< 1 2 250 >
每页显示 20 50 100
Diagnostic challenges and treatment approaches for hydatid cysts in atypical localizations
1
作者 Konstantin Semash Mikhail Voskanov 《World Journal of Nephrology》 2025年第3期13-19,共7页
Hydatid disease,caused by the Echinococcus granulosus parasite,is traditionally associated with liver and lung involvement.However,recent years have seen an increase in cases with atypical localizations,such as the ki... Hydatid disease,caused by the Echinococcus granulosus parasite,is traditionally associated with liver and lung involvement.However,recent years have seen an increase in cases with atypical localizations,such as the kidneys,thyroid,soft tissues,and bones.The study by Celik et al presents a series of five clinical cases where hydatid cysts were found in these rare anatomical regions,challenging conventional diagnostic and therapeutic approaches.The paper emphasizes the importance of differential diagnosis,as these cases can mimic other conditions,such as cancer,abscesses,or cysts.Advanced imaging techniques,such as com-puted tomography,magnetic resonance imaging,and ultrasound,play a crucial role in accurate diagnosis and help avoid misdiagnosis.The study demonstrates that early diagnosis and appropriate treatment of echinococosis in atypical localiz-ations are critical for preventing complications like cyst rupture and secondary infections.The use of albendazole and surgical intervention,especially in combi-nation with modern imaging techniques,yields good outcomes in these patients.However,several unanswered questions remain:What are the precise criteria for selecting the optimal treatment method in each case?What is the long-term effect-iveness of different approaches?Do patients with hydatid cysts in atypical lo-cations require additional monitoring and preventive treatment to avoid recu-rrence?Addressing these questions requires further research,and a multidisci-plinary approach involving radiologists,surgeons,and infectious disease spe-cialists is essential to optimize diagnosis and treatment.Early and accurate diagnostic methods based on differential diagnosis play a key role in improving treatment outcomes and reducing morbidity. 展开更多
关键词 ECHINOCOCCOSIS Echinococcosis granulosus Hydatid disease Atypical localization Diagnosis SURGERY Imaging Multidisciplinary management
暂未订购
Echinococcus granulosus in atypical localizations:Five case reports
2
作者 Ayse Sena Celik Hacer Yosunkaya +2 位作者 Aysel Yayilkan Ozyilmaz Kemal Bugra Memis Sonay Aydin 《World Journal of Nephrology》 2025年第2期158-167,共10页
BACKGROUND Hydatid cyst disease,caused by Echinococcus granulosus,primarily affects the liver and lungs,but it can also develop in rare locations such as the kidneys,thyroid,subcutaneous tissues,bones,and the mediasti... BACKGROUND Hydatid cyst disease,caused by Echinococcus granulosus,primarily affects the liver and lungs,but it can also develop in rare locations such as the kidneys,thyroid,subcutaneous tissues,bones,and the mediastinum.These atypical presentations often pose diagnostic challenges,as they can mimic benign and malignant pathologies,leading to potential misdiagnoses and inappropriate treatments.Early and accurate detection of hydatid cysts in uncommon sites is crucial for optimal patient management.CASE SUMMARY This case report series presents five patients with hydatid cysts located in atypical anatomical regions:The kidney,lumbar subcutaneous tissue,gluteal soft tissue,posterior mediastinum,and thyroid gland.The patients exhibited diverse clinical symptoms,including hematuria,palpable masses,localized pain,and chronic cough.Diagnosis was confirmed through a combination of imaging techniquesultrasound,computed tomography,and magnetic resonance imaging-along with serological testing.All cases were managed with antiparasitic therapy(albendazole),and in selected cases,surgical excision was performed to prevent complications such as cyst rupture or secondary infections.Post-treatment follow-up demonstrated complete resolution or stable cystic lesions,with no signs of recurrence.CONCLUSION Recognizing hydatid cysts in atypical locations is essential to avoid misdiagnosis and ensure appropriate treatment strategies.Radiological imaging plays a key role in distinguishing hydatid cysts from other cystic and neoplastic conditions,while serological tests can aid in confirmation,particularly in endemic regions.A multidisciplinary approach,integrating radiology,clinical evaluation,and surgical expertise,is critical for effective diagnosis and management.This report highlights the need for increased awareness of extrapulmonary and extravisceral hydatid disease,emphasizing its significance in differential diagnosis and clinical practice. 展开更多
关键词 Hydatid disease Atypical localization Renal hydatid disease Extrapulmonary hydatid disease Case report
暂未订购
Multiple subcellular localizations and functions of protein kinase Cδ in liver cancer
3
作者 Kohji Yamada Kiyotsugu Yoshida 《World Journal of Gastroenterology》 SCIE CAS 2022年第2期188-198,共11页
Protein kinase Cδ(PKCδ)is a member of the PKC family,and its implications have been reported in various biological and cancerous processes,including cell proliferation,cell death,tumor suppression,and tumor progress... Protein kinase Cδ(PKCδ)is a member of the PKC family,and its implications have been reported in various biological and cancerous processes,including cell proliferation,cell death,tumor suppression,and tumor progression.In liver cancer cells,accumulating reports show the bi-functional regulation of PKCδin cell death and survival.PKCδfunction is defined by various factors,such as phosphorylation,catalytic domain cleavage,and subcellular localization.PKCδhas multiple intracellular distribution patterns,ranging from the cytosol to the nucleus.We recently found a unique extracellular localization of PKCδin liver cancer and its growth factor-like function in liver cancer cells.In this review,we first discuss the structural features of PKCδand then focus on the functional diversity of PKCδbased on its subcellular localization,such as the nucleus,cell surface,and extracellular space.These findings improve our knowledge of PKCδinvolvement in the progression of liver cancer. 展开更多
关键词 Protein kinase Liver cancer Subcellular localization Tumor suppression Tumor progression
暂未订购
Extriangulated ideal quotients and Gabriel-Zisman localizations
4
作者 Yu Liu Panyue Zhou 《Science China Mathematics》 2025年第3期507-532,共26页
Let(B,E,s)be an extriangulated category and S be an extension closed subcategory of B.In this article,we prove that the Gabriel-Zisman localization B/S can be realized as an ideal quotient inside B when S satisfies so... Let(B,E,s)be an extriangulated category and S be an extension closed subcategory of B.In this article,we prove that the Gabriel-Zisman localization B/S can be realized as an ideal quotient inside B when S satisfies some mild conditions.The ideal quotient is an extriangulated category.We show that the equivalence between the ideal quotient and the localization preserves the extriangulated category structure.We also discuss the relations of our results with Hovey twin cotorsion pairs and Verdier quotients. 展开更多
关键词 cotorsion pairs extriangulated categories localizations quotient categories
原文传递
Tailoring of electromagnetic field localizations by twodimensional graphene nanostructures 被引量:4
5
作者 Ze-Bo Zheng Jun-Tao Li +9 位作者 Teng Ma Han-Lin Fang Wen-Cai Ren Jun Chen Jun-Cong She Yu Zhang Fei Liu Huan-Jun Chen Shao-Zhi Deng Ning-Sheng Xu 《Light: Science & Applications》 SCIE EI CAS CSCD 2017年第1期497-504,共8页
Graphene has great potential for enhancing light−matter interactions in a two-dimensional regime due to surface plasmons with low loss and strong light confinement.Further utilization of graphene in nanophotonics reli... Graphene has great potential for enhancing light−matter interactions in a two-dimensional regime due to surface plasmons with low loss and strong light confinement.Further utilization of graphene in nanophotonics relies on the precise control of light localization properties.Here,we demonstrate the tailoring of electromagnetic field localizations in the mid-infrared region by precisely shaping the graphene into nanostructures with different geometries.We generalize the phenomenological cavity model and employ nanoimaging techniques to quantitatively calculate and experimentally visualize the two-dimensional electromagnetic field distributions within the nanostructures,which indicate that the electromagnetic field can be shaped into specific patterns depending on the shapes and sizes of the nanostructures.Furthermore,we show that the light localization performance can be further improved by reducing the sizes of the nanostructures,where a lateral confinement of λ0/180 of the incidence light can be achieved.The electromagnetic field localizations within a nanostructure with a specific geometry can also be modulated by chemical doping.Our strategies can,in principle,be generalized to other two-dimensional materials,therefore providing new degrees of freedom for designing nanophotonic components capable of tailoring two-dimensional light confinement over a broad wavelength range. 展开更多
关键词 chemical doping electromagnetic field localizations GRAPHENE graphene nanostructures graphene plasmons
原文传递
A Deep Learning Framework for Heart Disease Prediction with Explainable Artificial Intelligence
6
作者 Muhammad Adil Nadeem Javaid +2 位作者 Imran Ahmed Abrar Ahmed Nabil Alrajeh 《Computers, Materials & Continua》 2026年第1期1944-1963,共20页
Heart disease remains a leading cause of mortality worldwide,emphasizing the urgent need for reliable and interpretable predictive models to support early diagnosis and timely intervention.However,existing Deep Learni... Heart disease remains a leading cause of mortality worldwide,emphasizing the urgent need for reliable and interpretable predictive models to support early diagnosis and timely intervention.However,existing Deep Learning(DL)approaches often face several limitations,including inefficient feature extraction,class imbalance,suboptimal classification performance,and limited interpretability,which collectively hinder their deployment in clinical settings.To address these challenges,we propose a novel DL framework for heart disease prediction that integrates a comprehensive preprocessing pipeline with an advanced classification architecture.The preprocessing stage involves label encoding and feature scaling.To address the issue of class imbalance inherent in the personal key indicators of the heart disease dataset,the localized random affine shadowsampling technique is employed,which enhances minority class representation while minimizing overfitting.At the core of the framework lies the Deep Residual Network(DeepResNet),which employs hierarchical residual transformations to facilitate efficient feature extraction and capture complex,non-linear relationships in the data.Experimental results demonstrate that the proposed model significantly outperforms existing techniques,achieving improvements of 3.26%in accuracy,3.16%in area under the receiver operating characteristics,1.09%in recall,and 1.07%in F1-score.Furthermore,robustness is validated using 10-fold crossvalidation,confirming the model’s generalizability across diverse data distributions.Moreover,model interpretability is ensured through the integration of Shapley additive explanations and local interpretable model-agnostic explanations,offering valuable insights into the contribution of individual features to model predictions.Overall,the proposed DL framework presents a robust,interpretable,and clinically applicable solution for heart disease prediction. 展开更多
关键词 Heart disease deep learning localized random affine shadowsampling local interpretable modelagnostic explanations shapley additive explanations 10-fold cross-validation
在线阅读 下载PDF
Multibipolar radiofrequency vs single needle microwave ablation for the treatment of newly diagnosed hepatocellular carcinoma
7
作者 Cécilia Bahloul Agnès Rode +6 位作者 Pierre Pradat Laurent Milot Jérôme Dumortier Philippe Merle Jean-Yves Mabrut Loïc Boussel Angelo Della Corte 《World Journal of Gastroenterology》 2026年第2期104-113,共10页
BACKGROUND Data comparing the outcomes of hepatocellular carcinoma(HCC)ablation by multibipolar radiofrequency ablation(mbp-RFA)and microwave ablation(MWA)are lacking.This study compares safety and efficacy of the two... BACKGROUND Data comparing the outcomes of hepatocellular carcinoma(HCC)ablation by multibipolar radiofrequency ablation(mbp-RFA)and microwave ablation(MWA)are lacking.This study compares safety and efficacy of the two techniques in treatment-naive HCC.AIM To compare the risk of local tumor progression(LTP)according to the technique;secondary endpoints included technique efficacy rate at one-month,overall survival and major complication rate.METHODS A bi-institutional retrospective analysis of patients undergoing treatment-naive HCC ablation by either technique was performed.Inverse probability of treatment weighting was used to compare the two groups.Mixed effects multivariate Cox regression was applied to identify risk factors for LTP.RESULTS A total of 362 patients(mean age,66.1±6.2 years,308 men)were included,of which 242(323 tumors)treated by mbp-RFA and 120(168 tumors)by MWA.After a median follow-up of 27 months,cumulative LTP was 11.4%after mbp-RFA and 25.2%after MWA.Independent risk factors for LTP at multivariate analysis were MWA(hazard ratio=2.85,P<0.001)and tumor size(hazard ratio=1.08,P<0.001).Two-year LTP-free survival was higher after mbp-RFA than MWA regardless of size(<3 cm:96%vs 87.1%,P<0.01;≥3 cm:87.5%vs 74%,P=0.04).Technique efficacy rate was higher after mbp-RFA(94.1%vs 87.5%,P=0.01).No difference was observed in major complication rate(9.5%vs 7.5%,P=0.59),nor 5-year overall survival(63.6%vs 58.3%,P=0.33).CONCLUSION Mbp-RFA leads to better local tumor control of treatment-naïve HCC than MWA regardless of tumor size and has better primary efficacy,while maintaining a comparable safety profile. 展开更多
关键词 Local tumor progression Ablation MICROWAVE RADIOFREQUENCY Hepatocellular carcinoma
暂未订购
Biomimetic Design of“Trunk-Branch-Leaf”Metallene Electrode for Efficient CO_(2) Electroreduction
8
作者 Min Zhang Ronghao Bai +3 位作者 Yuan Liang Xun Zhu Qian Fu Qiang Liao 《Carbon Energy》 2026年第1期95-104,共10页
Controllable synthesis of ultrathin metallene nanosheets and rational design of their spatial arrangement in favor of electrochemical catalysis are critical for their renewable energy applications.Here,a biomimetic de... Controllable synthesis of ultrathin metallene nanosheets and rational design of their spatial arrangement in favor of electrochemical catalysis are critical for their renewable energy applications.Here,a biomimetic design of“Trunk-Branch-Leaf”strategy is proposed to prepare the ultrathin edge-riched Zn-ene“leaves”with a thickness of~2.5 nm,adjacent Zn-ene cross-linked with each other,which are supported by copper nanoneedle“branches”on copper mesh“trunks,”named as Zn-ene/Cu-CM.The resulting superstructure enables the formation of an interconnected network and multiple channels,which can be used as an electrocatalytic CO_(2) reduction reaction(CO_(2)RR)electrode to allow a fast charge and mass transfer as well as a large electrolyte reservoir.By virtue of the distinctive structure,the obtained Zn-ene/Cu-CM electrode exhibits excellent selectivity and activity toward CO production with a maximum Faradaic efficiency of 91.3%and incredible partial current density up to 40 mA cm^(−2),outperforming most of the state-of-the-art Zn-based electrodes for CO_(2) reduction.The phenolphthalein color probe combined with in situ attenuated total reflection-infrared spectroscopy uncovered the formation of the localized pseudo-alkaline microenvironment at the interface of the Zn-ene/Cu-CM electrode.Theoretical calculations confirmed that the localized pH as the origin is responsible for the adsorption of CO_(2) at the interface and the generation of *COOH and *CO intermediates.This study offers valuable insights into developing efficient electrodes through synergistic regulation of reaction microenvironments and active sites,thereby facilitating the electrolysis of practical CO_(2) conversion. 展开更多
关键词 carbon dioxide reduction local pH metallene reaction microenvironment trunk-branch-lea
在线阅读 下载PDF
Efficacy and safety of immune checkpoint inhibitors plus chemotherapy in esophageal cancer patients with liver metastases
9
作者 En-Hui Dai Shu-Hao Que +7 位作者 Huan Xu Guo-Qiang Zhong Zhen Zhang Xu Liang Shu-Wei Zhai Yue-Tong Li Jing-Jing Wang Wei Feng 《World Journal of Gastrointestinal Oncology》 2026年第1期135-149,共15页
BACKGROUND The liver represents a common site of distant metastasis in patients with esophageal cancer(EC).Conventional chemotherapy(CMT)presents limited efficacy for EC,and EC patients with liver metastases typically... BACKGROUND The liver represents a common site of distant metastasis in patients with esophageal cancer(EC).Conventional chemotherapy(CMT)presents limited efficacy for EC,and EC patients with liver metastases typically experience a poor prognosis,highlighting an urgent need to explore novel treatment approaches.This study evaluated the overall efficacy and safety of CMT vs CMT combined with immune checkpoint inhibitors(ICIs)in the treatment of EC patients with liver metastases.Furthermore,prognostic factors influencing outcomes in this patient population were identified.AIM To evaluate the efficacy and safety of first-line chemoimmunotherapy for EC patients with liver metastases and to analyze prognostic factors.METHODS This retrospective study included 126 EC patients with liver metastases at Zhejiang Cancer Hospital between 2014 and 2024.Patients receiving CMT were compared with those receiving CMT+ICI.Analyzed variables included clinicopathological features,treatment history,characteristics of metastasis,systemic and local treatments,overall survival(OS),and treatment-related adverse events(TRAEs).Prognostic factors were evaluated using univariate and multivariate Cox proportional-hazards regression models.Finally,efficacy outcomes and TRAE profiles were compared between the two groups.RESULTS A significant difference in median OS was identified between the two groups(10.8 months in the CMT group vs 20.8 months in the CMT+ICI group,P=0.004).The CMT+ICI group also demonstrated a significantly longer median progression-free survival of 11.7 months(P<0.001).Patients receiving combination therapy exhibited significantly improved systemic objective response rate and disease control rate.Multivariate analysis identified key factors significantly influencing OS in EC patients with liver metastases:Karnofsky Performance Status score≥70,receipt of local therapy for liver metastases,and the number of cycles of CMT and immunotherapy received.Furthermore,the incidence of TRAEs did not significantly differ between the CMT+ICI and CMT groups.CONCLUSION For EC patients with liver metastases,the combination of CMT and ICIs demonstrates significantly superior efficacy compared with CMT alone,while maintaining manageable TRAEs. 展开更多
关键词 Esophageal cancer Liver metastasis CHEMOTHERAPY IMMUNOTHERAPY Local liver-directed therapy
暂未订购
Niche vs.habitat:Insights of aging microplastics and wetland types on bacterial community assembly
10
作者 Yansong Shi Longrui Liang +1 位作者 Liang Meng Jingwen Hou 《Journal of Environmental Sciences》 2026年第1期221-232,共12页
Microorganisms can colonize the surface of microplastics(MPs)to form a distinctive microbiome,known as a“plastisphere”which is regarded as an anthropogenic niche for microbial growth.However,bacterial community asse... Microorganisms can colonize the surface of microplastics(MPs)to form a distinctive microbiome,known as a“plastisphere”which is regarded as an anthropogenic niche for microbial growth.However,bacterial community assembly in virgin and aging MP plastispheres across different habitats is poorly understood.This study aims to assess the variations in bacterial community assembly across different niches and habitats with an in situ ex-periment,in which constructed forest wetland(FW),natural lake wetland(LW),and lotus pond wetland(LP)were habitats,and plastispheres of virgin and aging low-density polyethylene(LDPE)MPs,as well as surround-ing wetland soils were niches.Significant niche-related differences in bacterial communities were observed,with lower diversity and enrichment of potential plastic-degrading bacteria in the plastisphere than in the soil bacterial communities.Furthermore,habitat-related differences exerted a more pronounced influence on the beta-diversity patterns of the bacterial communities.The linear regression analyses indicated that the local species pool con-tributed more to bacterial community assembly in the LW wetland,whereas the relative abundance of species was the primary factor in the LP wetland.The null model analysis indicated that plastisphere bacterial communi-ties were predominantly driven by the stochastic process,with a more deterministic assembly observed in the LP wetland and soil bacterial communities.Additionally,the primary ecological process shaping plastisphere com-munities shifted from drift in the virgin LDPE to homogenising dispersal in the aging LDPE.This study provides new insights into the fate and ecological impacts of MPs in wetlands,thereby facilitating the effective regulations of plastic pollution. 展开更多
关键词 Plastisphere Community assembly mechanism Local species pool Stochastic assembly Homogeneous process
原文传递
A Boundary Element Reconstruction (BER) Model for Moving Morphable Component Topology Optimization
11
作者 Zhao Li Hongyu Xu +2 位作者 Shuai Zhang Jintao Cui Xiaofeng Liu 《Computers, Materials & Continua》 2026年第1期2213-2230,共18页
The moving morphable component(MMC)topology optimization method,as a typical explicit topology optimization method,has been widely concerned.In the MMC topology optimization framework,the surrogate material model is m... The moving morphable component(MMC)topology optimization method,as a typical explicit topology optimization method,has been widely concerned.In the MMC topology optimization framework,the surrogate material model is mainly used for finite element analysis at present,and the effectiveness of the surrogate material model has been fully confirmed.However,there are some accuracy problems when dealing with boundary elements using the surrogate material model,which will affect the topology optimization results.In this study,a boundary element reconstruction(BER)model is proposed based on the surrogate material model under the MMC topology optimization framework to improve the accuracy of topology optimization.The proposed BER model can reconstruct the boundary elements by refining the local meshes and obtaining new nodes in boundary elements.Then the density of boundary elements is recalculated using the new node information,which is more accurate than the original model.Based on the new density of boundary elements,the material properties and volume information of the boundary elements are updated.Compared with other finite element analysis methods,the BER model is simple and feasible and can improve computational accuracy.Finally,the effectiveness and superiority of the proposed method are verified by comparing it with the optimization results of the original surrogate material model through several numerical examples. 展开更多
关键词 Topology optimization MMC method boundary element reconstruction surrogate material model local mesh
在线阅读 下载PDF
Intriguing role of the Golgi apparatus in astrocyte function:Implications for disorders
12
作者 Martina Polenghi Elena Restelli +1 位作者 Elena Taverna Laura Tapella 《Neural Regeneration Research》 2026年第7期2555-2562,共8页
Cell function has a tight relationship with cell architecture.Distribution of proteins to the correct compartment is one of the functions of the traffic pathway through the Golgi apparatus.The others are to ensure pro... Cell function has a tight relationship with cell architecture.Distribution of proteins to the correct compartment is one of the functions of the traffic pathway through the Golgi apparatus.The others are to ensure proper protein folding,the addition of post-translational modifications,and delivering to intracellular and extracellular destinations.Astrocytes are fundamental homeostatic cells,controlling multiple aspects of the central nervous system physiology,such as ion balance,nutrients,blood flow,neurotransmitters,and responses to insults.Astrocytes are polarized cells,and,such as neurons,extensively use the secretory pathway for secreting factors and exposing functional receptors,channels,and transporters on the plasma membrane.In this review,we will underline the importance of studying the Golgi apparatus and the secretory pathway in astrocytes,based on the possible tight connection between the Golgi apparatus and astrocytes’homeostatic function.Given the topic of this review,we will provide examples mostly about the Golgi apparatus structure,function,localization,and its involvement in astrocytes’homeostatic response,with an insight into congenital glycosylation disorders,as an example of a potential future field in the study of astrocyte homeostatic failure and Golgi apparatus alteration. 展开更多
关键词 ASTROCYTES congenital glycosylation disorders GLIA Golgi apparatus homeostatic function local protein translation neurodegeneration neuroinflammation neuronal development secretory pathway
暂未订购
Enabling Intrinsic Antiferroelectricity in Two-dimensional NbOCl_(2):Molecular Dynamics Simulations based on Deep Learning Interatomic Potential
13
作者 Jiawei Mao Yinglu Jia +2 位作者 Gaoyang Gou Shi Liu Xiao Cheng Zeng 《Chinese Physics Letters》 2026年第1期156-178,共23页
Compared to the well-studied two-dimensional(2D)ferroelectricity,the appearance of 2D antiferroelectricity is much rarer,where local dipoles from the nonequivalent sublattices within 2D monolayers are oppositely orien... Compared to the well-studied two-dimensional(2D)ferroelectricity,the appearance of 2D antiferroelectricity is much rarer,where local dipoles from the nonequivalent sublattices within 2D monolayers are oppositely oriented.Using NbOCl_(2) monolayer with competing ferroelectric(FE)and antiferroelectric(AFE)phases as a 2D material platform,we demonstrate the emergence of intrinsic antiferroelectricity in NbOCl_(2) monolayer under experimentally accessible shear strain,along with new functionality associated with electric field-induced AFE-to-FE phase transition.Specifically,the complex configuration space accommodating FE and AFE phases,polarization switching kinetics,and finite temperature thermodynamic properties of 2D NbOCl_(2) are all accurately predicted by large-scale molecular dynamics simulations based on deep learning interatomic potential model.Moreover,room temperature stable antiferroelectricity with low polarization switching barrier and one-dimensional collinear polarization arrangement is predicted in shear-deformed NbOCl_(2) monolayer.The transition from AFE to FE phase in 2D NbOCl_(2) can be triggered by a low critical electric field,leading to a double polarization–electric(P–E)loop with small hysteresis.A new type of optoelectronic device composed of AFE-NbOCl_(2) is proposed,enabling electric“writing”and nonlinear optical“reading”logical operation with fast operation speed and low power consumption. 展开更多
关键词 d monolayers local dipoles nonequivalent sublattices intrinsic antiferroelectricity two dimensional nbocl d antiferroelectricity experimentally accessible shear strainalong molecular dynamics simulations
原文传递
Subcellular Localizations of AS1 and AS2 Suggest Their Common and Distinct Roles in Plant Development 被引量:1
14
作者 Yan Zhu Ziyu Li +4 位作者 Ben Xu Hongda Li Lingjian Wang Aiwu Dong Hai Huang 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2008年第7期897-905,共9页
During leaf organogenesis, a critical step for normal leaf primordium initiation is the repression of the class 1 KNOTTED1-like homeobox (KNOX) genes. After leaf primordia are formed, they must establish polarity fo... During leaf organogenesis, a critical step for normal leaf primordium initiation is the repression of the class 1 KNOTTED1-like homeobox (KNOX) genes. After leaf primordia are formed, they must establish polarity for normal leaf morphogenesis. Recent studies have led to the identification of a number of genes that participate in the class 1 KNOX gene repression and/or the leaf polarity establishment. ASTMMETRIC LEAVES1 and 2 (AS1 and AS2) are two of these genes, which are critical for both of these two processes. As a first step towards understanding the molecular genetic basis of the ASl-AS2 action, we determined the subcellular Iocalizations of the two proteins in both tobacco BY2 cells and Arabidopsis plants, by fusing them to yellow/cyan fluorescent protein (YFP/CFP). Our data showed that AS1 and AS2 alone were predominantly localized in the nucleolus and the nucleoplasm, respectively. The presence of both AS1 and AS2 proteins in the same interphase cell demonstrated their co-localization in both nucleolus and nucleoplasm. In addition, AS1 alone was able to associate with the condensed chromosome in the metaphase cell. Our data suggest that AS1, AS2 and the ASl-AS2 protein complex may have distinct functions, which are all required for normal plant development. 展开更多
关键词 ARABIDOPSIS asymmetric leaves1/2 leaf development subcellular localization.
原文传递
Microscopic and ultramicroscopic localizations and quantitative analysis of 5-HT receptors in human placentas
15
作者 Weiquan Huang Chongli Zhang +1 位作者 Xinyu Di Lan Sun 《Chinese Science Bulletin》 SCIE EI CAS 1998年第10期804-809,共6页
The localizations of 5-hydroxytryptamine receptor (5-HTR) at light and electron microscopic levels and its quantitative analysis in human placentas were studied by using immunohistochemistry and in situ hybridization.... The localizations of 5-hydroxytryptamine receptor (5-HTR) at light and electron microscopic levels and its quantitative analysis in human placentas were studied by using immunohistochemistry and in situ hybridization. Both syncytiotrophoblast and cytotrophoblast in placental villi and fetal white blood cells in villose capillary cavity showed 5-HT receptor immunoreactivity, with 5-HT 1A receptor mRNA hybridized signal detected in cytoplasm. But the stromal cells and capillary endothelium in placental villi showed 5-HT receptor immunoreactivity in cytoplasm, without 5_HT\-1A receptor mRNA hybridized signal detected. This suggested that two layers of trophoblast cells may produce 5-HT 1 and 5-HT 2 receptors, that the stromal cells and capillary endothelium in placental villi may only produce 5-HT 2 receptor. By immunohistochemistry at electron microscopic level, the small flattened vesicles and large dense cored vesicle within trophoblast cells showed 5-HT receptor immunoreactivity. This suggested that it may be the result of 5-HT receptors internalization and transportion. Using a quantitative immunohistochemical method, the contents of 5-HT receptor in placenta were higher during the 6th week of gestation, and decreased in 7th and 8th, reoccurred the second peak in the 9th, reduced gradually during the 10th, 20th and 40th of the gestation period. These changes paralleled the contents of 5-HT in the authors’ studies, reflecting that 5-HT may be one of the most important bioactive substances in placental self-regulation. 展开更多
关键词 HT receptor localization quantitative determination IMMUNOHISTOCHEMISTRY in SITU HYBRIDIZATION human placenta.
在线阅读 下载PDF
BiO_(2-x)Nanosheets with Surface Electron Localizations for Efficient Electrocatalytic CO_(2)Reduction to Formate
16
作者 Zhonghao Tan Jianling Zhang +6 位作者 Yisen Yang Yufei Sha Ran Duan Jiajun Zhong Buxing Han Jingyang Hu Yingzhe Zhao 《CCS Chemistry》 CAS CSCD 2023年第1期133-144,共12页
To enhance the activity and selectivity of electrocatalytic CO_(2)reduction to formate is of great importance from both environmental and economical viewpoints.Herein,the BiO_(2-x)nanosheets with surface electron loca... To enhance the activity and selectivity of electrocatalytic CO_(2)reduction to formate is of great importance from both environmental and economical viewpoints.Herein,the BiO_(2-x)nanosheets with surface electron localizations were constructed and utilized for the efficient CO_(2)-to-formate conversion.The formate Faraday efficiency reaches 99.1%with current density of 12 mA cm^(−2)at^(−1).1 V versus the reversible hydrogen electrode(RHE)in an H-type cell while those in the flow cell are 91.3%and 319 mA cm^(−2)at^(−1).0 V versus RHE,respectively.Theoretical calculations indicate that the electron localization presenting in the BiO_(2-x)nanosheet favors OCHO*intermediate stabilization and suppresses H*intermediate adsorption,thus improving the CO_(2)-to-formate efficiency.The BiO_(2-x)electrocatalyst is nondopant,easily prepared,low-cost,highly active and selective for CO_(2)RR to formate,which has demonstrated potential for application in the Zn-CO_(2)battery.The maximum power density can reach 2.33 mW cm^(−2),and the charge/discharge cycling stability is>100 h(300 cycles)at 4.5 mA cm^(−2). 展开更多
关键词 BiO_(2-x) electron localization CO_(2)electroreduction FORMATE Zn-CO_(2)battery
在线阅读 下载PDF
Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel 被引量:1
17
作者 Mei Zhang Wenhao Li +3 位作者 Yangfei Chen Yang Jiang Xiaofei Guo Han Dong 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期369-379,共11页
The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile testing.In-situ observations under scanning electron microscopy,transmiss... The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile testing.In-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation mechanisms.These findings were discussed with the local strain measurements via digital image correlation.The results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of yielding.The small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier effect.The volume fraction of RA gradually decreased from 26.8%to 8.2%prior to fracture.In the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase. 展开更多
关键词 medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation
在线阅读 下载PDF
Local Rate of Convergence in the Functional Limit Theorem for Increments of a Fractional Brownian Motion 被引量:1
18
作者 LIU Yonghong DING Ding ZHOU Xia 《数学进展》 北大核心 2025年第1期197-211,共15页
In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):104... In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):1045-1049]and Monrad and Rootzén[Probab.Theory Related Fields,1995,101(2):173-192]. 展开更多
关键词 fractional Brownian motion INCREMENT local functional law of the iterated logarithm large deviation small deviation
原文传递
基于红外图像分割的复合绝缘子过热识别方法
19
作者 宁雪峰 李龙 +1 位作者 韦薇 袁超 《激光与红外》 北大核心 2025年第12期1897-1904,共8页
现有基于红外图像的绝缘子发热缺陷识别方法,存在目标区域提取精度有限、温度提取受环境因素影响较大等问题。为此,本文提出一种复合绝缘子过热识别新方法:首先改进单阶段绝缘子实例分割算法You Only Look At CoefficienTs(YOLACT),引... 现有基于红外图像的绝缘子发热缺陷识别方法,存在目标区域提取精度有限、温度提取受环境因素影响较大等问题。为此,本文提出一种复合绝缘子过热识别新方法:首先改进单阶段绝缘子实例分割算法You Only Look At CoefficienTs(YOLACT),引入嵌有Efficient Local Attention(ELA)机制的MobileNetV2作主干网络提升检测速度,融合特征金字塔网络(Feature Pyramid Network,FPN)各层特征图并加入聚焦纯卷积特征提取模块提高特征图质量;然后使用改进算法识别红外图像中复合绝缘子外轮廓,定位其棒芯位置;最后依据红外图像热矩阵获取棒芯温度矩阵,对比温度变化判断是否异常。实际生产环境中,本文方法整体准确率达到975,算法总耗时125ms;改进实例分割算法平均交互比(mIOU)为9297,平均像素准确率(mPA)为9615,每秒帧数(FPS)为19。结果显示,此方法分割定位效果好,能滤除多数环境因素导致的温度识别误差,为绝缘子温度异常识别提供新方案。 展开更多
关键词 红外图像 绝缘子发热缺陷 You Only Look At CoefficienTs实例分割算法 MobileNetV2网络 Efficient Local Attention机制 聚焦纯卷积特征提取模块
在线阅读 下载PDF
航空发动机涡轮叶片线阵CT断层图像轮廓提取与评价
20
作者 俞梦倩 吴伟 +1 位作者 宋艳艳 王克广 《航空制造技术》 北大核心 2025年第22期160-167,共8页
工业CT线阵扫描是获取航空发动机涡轮叶片内部特征结构的重要方法,提取重建断层灰度图像轮廓是测量叶片壁厚等尺寸的关键步骤。由于目前常用像素级无监督评价方法存在提取边缘模糊,以及尺寸测量精度不高的问题,本文提出一种基于智能参... 工业CT线阵扫描是获取航空发动机涡轮叶片内部特征结构的重要方法,提取重建断层灰度图像轮廓是测量叶片壁厚等尺寸的关键步骤。由于目前常用像素级无监督评价方法存在提取边缘模糊,以及尺寸测量精度不高的问题,本文提出一种基于智能参数优化的数模匹配亚像素级轮廓提取算法。首先采用LBF几何活动轮廓模型提取边缘,在CAD模型上获取对应截面点云;然后通过OBB方向包围盒算法将两者坐标统一,以Hausdorff距离建立评价函数;最后基于蜣螂智能优化算法,对LBF模型中正则项系数等4个参数寻优,使得轮廓提取达到最佳。叶片CT断层图像测试结果表明,相对误差小于1.6%,相比于传统的Canny、Ostu以及Zernike等边缘检测算法,本文算法可以显著提高测量精度。 展开更多
关键词 航空发动机涡轮叶片 CT断层图像 LBF(Local binary fitting)模型 蜣螂优化算法(Dung beetle optimizer DBO) 方向包围盒(OBB)
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部