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Anopheles gambiae larvicidal and adulticidal potential of Phyllanthus amarus(Schumach and Thonn,1827)obtained from different localities of Nigeria
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作者 Kingsley Uchenna Ozioko Chris Ikem Okoye +1 位作者 Fabian Chukwuemenam Okafor Rose Nduka Obiezue 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2021年第1期27-33,共7页
Objective:To screen phytochemicals in ethanolic leaf extracts of Phyllanthus amarus collected from three different geographical zones in Nigeria and evaluate their effects on larva and adult of Anopheles gambiae.Metho... Objective:To screen phytochemicals in ethanolic leaf extracts of Phyllanthus amarus collected from three different geographical zones in Nigeria and evaluate their effects on larva and adult of Anopheles gambiae.Methods:The sample extracts of Phyllanthus amarus prepared with ethanol solvent were tested against Anopheles gambiae at two important developmental stages of its life cycle using slightly modified WHO protocols.Results:Alkaloids,saponins,tannins,flavonoids,glycosides,phenols,and terpenes were detected in each extract.Among these samples,the extract from northwest exhibited the highest larvicidal activity(LC50=263.02 ppm),followed by southeast and southwest extracts(LC50=288.40 and 295.12 ppm,respectively after 48 h),while the extract from southwest exhibited the highest adulticidal activity(LC50=275.42 ppm),followed by northwest and southeast extract(LC50=301.99 and 316.22 ppm,respectively after 24 h).A 50%larva mortality was almost attained at 600 ppm after 48 h duration of exposure to the northwest extract.Conclusions:The tested samples possess strong larvicidal and adulticidal property against Anopheles gambiae which depends on their chemical composition and localities of collection.Further studies are needed to explore the insecticidal activity against a wider range of mosquito species,and to identify active ingredient(s)of the extract responsible for such activity. 展开更多
关键词 Adulticidal Anopheles gambiae Different localities LARVICIDAL Phyllanthus amarus
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Hierarchy of Rural Localities in the Niakhar Area (Fatick, Senegal)
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作者 Alphousseyni Ndonky Mouhamadou Moustapha Mbacké Ndour +2 位作者 Ibrahima Ndiaye Richard Lalou Pape Boubou Sow 《Journal of Geographic Information System》 2022年第3期221-239,共19页
Although the study of the hierarchy of localities presents an important social and economic stake, studies focused on the hierarchy of rural localities are relatively weak, especially in Africa. It is important to hig... Although the study of the hierarchy of localities presents an important social and economic stake, studies focused on the hierarchy of rural localities are relatively weak, especially in Africa. It is important to highlight the hierarchy of rural areas in order to reveal poles that can support sustainable growth. Our main objective is to study the hierarchy of rural localities in the Niakhar area, using a geographic approach. The data come from the Niakhar demographic, epidemiological and environmental observatory database and the Niakhar Atlas project of the French Research Institute for Development (IRD). The net flow method, the primacy index, the median population threshold method and the measurement of the correlation between level of centrality and population size are used to analyze the data. Our study allowed us to determine the main types of centrality and to establish the hierarchy of rural localities in the Niakhar zone. It also highlighted the strong correlation between the rank of localities and the size of the population of the latter. The main contribution of our work is to have highlighted, in order, the structuring localities of the rural space of the Niakhar area, by combining several indicators of centrality. 展开更多
关键词 HIERARCHY Rural localities CENTRALITY Population Size Service Functions ATTRACTIVENESS
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Xi Story:Blazing a High-Quality Development Path Suited to Local Conditions
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《Women of China》 2026年第3期6-7,共2页
BEIJING,Feb.25(Xinhua)-In a territory more than twice the size of the European Union and where per capita GDP varies up to fourfold across provincia level regions,the challenge of modernizing China with the right solu... BEIJING,Feb.25(Xinhua)-In a territory more than twice the size of the European Union and where per capita GDP varies up to fourfold across provincia level regions,the challenge of modernizing China with the right solutions for diverse localities has become a test of governance wisdom. 展开更多
关键词 high quality development per capita gdp local conditions modernizing china diverse localities governance wisdom
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Global-local feature optimization based RGB-IR fusion object detection on drone view 被引量:1
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作者 Zhaodong CHEN Hongbing JI Yongquan ZHANG 《Chinese Journal of Aeronautics》 2026年第1期436-453,共18页
Visible and infrared(RGB-IR)fusion object detection plays an important role in security,disaster relief,etc.In recent years,deep-learning-based RGB-IR fusion detection methods have been developing rapidly,but still st... Visible and infrared(RGB-IR)fusion object detection plays an important role in security,disaster relief,etc.In recent years,deep-learning-based RGB-IR fusion detection methods have been developing rapidly,but still struggle to deal with the complex and changing scenarios captured by drones,mainly due to two reasons:(A)RGB-IR fusion detectors are susceptible to inferior inputs that degrade performance and stability.(B)RGB-IR fusion detectors are susceptible to redundant features that reduce accuracy and efficiency.In this paper,an innovative RGB-IR fusion detection framework based on global-local feature optimization,named GLFDet,is proposed to improve the detection performance and efficiency of drone-captured objects.The key components of GLFDet include a Global Feature Optimization(GFO)module,a Local Feature Optimization(LFO)module and a Channel Separation Fusion(CSF)module.Specifically,GFO calculates the information content of the input image from the frequency domain and optimizes the features holistically.Then,LFO dynamically selects high-value features and filters out low-value features before fusion,which significantly improves the efficiency of fusion.Finally,CSF fuses the RGB and IR features across the corresponding channels,which avoids the rearrangement of the channel relationships and enhances the model stability.Extensive experimental results show that the proposed method achieves the best performance on three popular RGB-IR datasets Drone Vehicle,VEDAI,and LLVIP.In addition,GLFDet is more lightweight than other comparable models,making it more appealing to edge devices such as drones.The code is available at https://github.com/lao chen330/GLFDet. 展开更多
关键词 Object detection Deep learning RGB-IR fusion DRONES Global feature Local feature
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Screening and determination of 23 local anesthetics in cosmetics using UPLC-Q-TOF-MS and HPLC-QQQ-MS/MS
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作者 Ruotong Yang Fangyuan Wu +3 位作者 Guangqian Xu Guiwen Guo Haiyan Wang Lingyun Jia 《日用化学工业(中英文)》 北大核心 2026年第2期260-270,共11页
The laboratory established an efficient reversed-phase ultra-high-performance liquid chromatographyquadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS)qualitative method for screening more than 2000 kinds of ris... The laboratory established an efficient reversed-phase ultra-high-performance liquid chromatographyquadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS)qualitative method for screening more than 2000 kinds of risk substances(including local anesthetics,LAs)in cosmetics,which has been successfully applied in the analysis of actual samples.This work aims to develop a more convenient high performance liquid chromatography triple quadrupole mass spectrometry(HPLC-QQQ-MS/MS)method for the quantitative determination of LAs.Samples were ultrasonically extracted with methanol,separated on an Agilent Poroshell 120 EC-C18 column(2.1 mm×100 mm,2.7μm),and eluted with a gradient mobile phase consisting of 0.1%formic acid aqueous solution and methanol.Quantification was performed using the external standard method.The results show that all 23 LAs are effectively separated within 12 minutes,with good linearity in the corresponding concentration ranges and the correlation coefficients all greater than 0.99.The limits of detection(LOD)range from 0.0025 to 0.05μg/g,and the limits of quantification(LOQ)range from 0.01 to 0.1μg/g.The average recoveries of the 23 LAs in 5 blank cosmetic matrices are 80.68%-117.57%,with the relative standard deviations(RSDs)less than 5.98%.This method has good precision and high accuracy,and is suitable for the determination of LAs in 5 cosmetic matrices. 展开更多
关键词 local anesthetics chemical analysis ultra-high-performance liquid chromatography-quadrupole time-offlight mass spectrometry(UPLC-Q-TOF-MS) high performance liquid chromatography triple quadrupole mass spectrometry(HPLC-QQQ-MS/MS)
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Above,Below,and Beyond:Distinct Vertical-Plane Localization Profiles in Normal Hearing Listeners
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作者 Harshada Mali Nisha K.V. 《Journal of Otology》 2026年第1期27-34,共8页
Background and Objectives:The perception of sound in the vertical plane supports spatial hearing by enabling listeners to detect sources located above and below.Sounds originating from both the front and back elevatio... Background and Objectives:The perception of sound in the vertical plane supports spatial hearing by enabling listeners to detect sources located above and below.Sounds originating from both the front and back elevations along the mid-sagittal plane further contribute to a three-dimensional auditory experience.This study aimed to characterize the variability in vertical sound localization abilities among normal-hearing(NH)individuals using spatialized audio.Materials and Methods:Fifty-one NH participants(aged 18 to 35 years)completed three vertical localization tasks under headphones as part of a single-group,within-subject experimental study.These tasks included two-plane identification:(1)top-down localization,(2)front-back localization,and one discrimination task in the front plane.Hierarchical Cluster Analysis(HCA)was employed to identify distinct patterns in spatial localization profiles specific to the vertical-median plane.Fisher's Discriminant Function Analysis(FDA)was used to validate the accuracy of HCA and estimate classification error.Results:HCA revealed three distinct listener clusters:(1)cluster 1 with good performance across all three tasks,(2)cluster 2 with selective impairment in top-bottom identification,and(3)cluster 3 with selective deficits in front-back identification.FDA validated group membership of the clusters identified by the HCA,with a prediction accuracy of 98%.Conclusions:Individuals with clinically NH exhibited three distinct vertical localization profiles:uniform performers,those impaired in top-bottom identification,and those impaired in front-back identification.These profiles may be linked to the interplay between acoustic and non-acoustic perceptual factors. 展开更多
关键词 Vertical-plane sound localization Spatial Hearing Localization accuracy Virtual Assessment DISCRIMINATION
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A Deep Learning Framework for Heart Disease Prediction with Explainable Artificial Intelligence
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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
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Openness in a Century-Old Community
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作者 XIA YUANYUAN 《China Today》 2026年第3期44-47,共4页
Local residents,artists,and entrepreneurs who converge on Haikou’s historical Qilou Street are contributing to a new chapter in the story of Hainan’s opening-up.MORE than 100 years ago,the area alongQilou(Sotto Port... Local residents,artists,and entrepreneurs who converge on Haikou’s historical Qilou Street are contributing to a new chapter in the story of Hainan’s opening-up.MORE than 100 years ago,the area alongQilou(Sotto Portico)Street in Haikou,capital of Hainan Province,served asthe embarkation point for Hainanesesetting out on their maritime voyages to seek greener pastures. 展开更多
关键词 ARTISTS OPENNESS HAINAN local residents qilou street ENTREPRENEURS Haikou maritime voyages
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Multibipolar radiofrequency vs single needle microwave ablation for the treatment of newly diagnosed hepatocellular carcinoma
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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
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Polar-localized EXO70G1 regulates root development in Arabidopsis thaliana
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作者 Juan Li Zhendong Liu +9 位作者 Lixue Gong Shuju Zhao Qing Lu Shan Gao Su Jiang Xiaonan Liu Long Ma Guangyou Duan Dayong Cui Shipeng Li 《Journal of Integrative Plant Biology》 2026年第1期96-112,共17页
Cellular asymmetry,which represents a fundamental characteristic of cell polarity,is prominently illustrated by the apical-basal localization of PINFORMED(PIN)auxin efflux carriers in Arabidopsis thaliana.Although the... Cellular asymmetry,which represents a fundamental characteristic of cell polarity,is prominently illustrated by the apical-basal localization of PINFORMED(PIN)auxin efflux carriers in Arabidopsis thaliana.Although the maintenance of PIN polarity at the plasma membrane(PM)relies on endomembrane trafficking,the pivotal factors responsible for recruiting PIN proteins to the PM remain largely unknown.In this study,we discover that EXO70G1displays a polarized distribution at the PM in root cells.Acting as a putative subunit of the exocyst complex,which mediates the tethering of exocytic vesicles to the PM,EXO70G1 exhibits continuous recycling foci at the PM,and its dynamic behavior is akin to that of SEC6 and SEC8.Disruption of EXO70G1 and its homolog EXO70G2 in Arabidopsis reduces auxin accumulation and primary root length.Importantly,the recycling of PIN2 from the brefeldin A(BFA)compartment to the PM is compromised,and the abundance of PIN2 at the PM is reduced in the exo70G1 exo70G2 backgrounds.Interestingly,live-cell imaging reveals that the polarity of EXO70G1 is established during cytokinesis,prior to that of PIN2,and is maintained throughout the subsequent phases of cell elongation and differentiation.When the lipid raft was disturbed,the accumulation of EXO70G1 at the PM decreased.Our findings highlight the crucial role of EXO70G1 in root development by providing positional cues that facilitate the recycling efficiency of PIN2 to the PM. 展开更多
关键词 endomembrane trafficking EXO70 PIN polar localization root development
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Deep learning-based method for damage identification and localization of the maglev track stator surface
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作者 Shihua Huang Tiange Wang Guofeng Zeng 《High-Speed Railway》 2026年第1期21-26,共6页
The stator of the maglev track plays a crucial role in the operation of the maglev system.Currently,the efficiency of maglev track inspection is limited by several factors,including the large span of elevated structur... The stator of the maglev track plays a crucial role in the operation of the maglev system.Currently,the efficiency of maglev track inspection is limited by several factors,including the large span of elevated structures,manual visual inspection,short inspection window times,and limited GPS positioning accuracy.To address these issues,this paper proposes a deep learning-based method for detecting and locating stator surface damage.This study establishes a maglev track stator surface image dataset,trains different object detection models,and compares their performance.Ultimately,YOLO and ByteTrack object tracking algorithms were chosen as the basic framework and enhanced to achieve automatic identification of high-speed maglev track stator surface damage images and track and count stator surface localization feature images.By matching the identified damaged images with their corresponding stator segment and beam segment sequence numbers,the location of the damage is pinpointed to the corresponding stator segment,enabling rapid and accurate identification and localization of complex damage to the maglev track stator surface. 展开更多
关键词 Maglev track Damage recognition Precise localization Deep learning TRACKING
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Biomimetic Design of“Trunk-Branch-Leaf”Metallene Electrode for Efficient CO_(2) Electroreduction
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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
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Efficacy and safety of immune checkpoint inhibitors plus chemotherapy in esophageal cancer patients with liver metastases
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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
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Analysis of Histochemical Localization and Content Influencing Factors of Saponins in Pseudostellaria heterophylla
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作者 Huiqing PAN Yanda ZHANG +3 位作者 Zhenhua WANG Qi ZHAO Zuyun YE Xin WANG 《Medicinal Plant》 2026年第1期5-9,19,共6页
This paper provides a systematic review of the histochemical localization,content characteristics,and influencing factors of saponins in Pseudostellaria heterophylla based on an extensive literature survey.It provides... This paper provides a systematic review of the histochemical localization,content characteristics,and influencing factors of saponins in Pseudostellaria heterophylla based on an extensive literature survey.It provides an in-depth analysis and summary of the effects of biological factors,environmental conditions,agronomic practices,processing methods,and continuous cropping obstacles on the synthesis of P.heterophylla saponins,as well as their underlying mechanisms.Based on identified gaps in the current literature,future research directions and prospects are proposed.The findings of this review offer valuable insights for advancing the understanding of the saponin biosynthesis mechanisms in P.heterophylla and for enhancing its quality. 展开更多
关键词 Pseudostellaria heterophylla SAPONIN Histochemical localization Content influencing factors Research progress
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Multi-pass intermittent local loading process of large-scale rib-web component:Forming characteristics and implementing apparatus
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作者 Dawei ZHANG Peng DONG +2 位作者 Jingxiang LI Zijian YU Shengdun ZHAO 《Chinese Journal of Aeronautics》 2026年第1期601-625,共25页
The multi-pass intermittent local loading process,which features a more flexible processing path,can further enhance the second material distribution during local loading,improve the formability of components,and redu... The multi-pass intermittent local loading process,which features a more flexible processing path,can further enhance the second material distribution during local loading,improve the formability of components,and reduce forming loads.However,the absence of compatible forming equipment makes it difficult to control the constraint in the unloaded zones during the forming process.This difficulty complicates coordination and control of deformation,particularly for asymmetric rib-web components.Additionally,the current implementation involves multi-fire heating,a long process flow,and high energy consumption,which limits the popularization and application of the local loading process.In this study,a new multi-pass local loading hydraulic forming apparatus that can quickly and reliably switch between heavy-load deformation and low-load constraint for different local loading sub-dies was developed.A 10-tonne laboratory prototype was developed,and the forming characteristics during the forming process as well as the response characteristics of the hydraulic system during the multi-pass intermittent local loading of rib-web component were investigated using numerical simulations and physical experiments.Results indicated that,compared to a whole loading process with the same initial geometry of billet,the total forming load(i.e.,the sum of loaded and restrained loads)is reduced by more than 40%with the local loading process,and by nearly 50%with multi-pass local loading.The multi-pass local loading process allows for more effective control of material flow compared to single-pass local loading,leading to improved cavity filling and reduced flow line disturbance.For a large-scale,complex titanium alloy bulkhead,the cavity filling problem was addressed by optimizing the multi-pass local loading path with an unequal thickness billet.The dynamic performance of the multi-pass local loading hydraulic system was found to be robust,with stable pressure transitions during motion and load switching for the sub-die(s).The dynamic characteristic of the hydraulic cylinder when switching from non-moving/unloaded state to a moving/loading state are consistent whether a load is present or not.However,the dynamic characteristics differ when switching from a moving/loading state to non-moving/unloaded state,showing opposite behavior.The developed hydraulic drive mechanism provides a way for implementation of multi-pass local loading without auxiliary operation and extra heating.The results of the study provide a foundation for the industrial production of large-scale,complex components with reduced force requirement and low-energy consumption. 展开更多
关键词 Forming characteristics Hydraulic system Intermittent local loading process Material flow Rib-web component
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Beyond Wi-Fi 7:Enhanced Decentralized Wireless Local Area Networks with Federated Reinforcement Learning
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作者 Rashid Ali Alaa Omran Almagrabi 《Computers, Materials & Continua》 2026年第3期391-409,共19页
Wi-Fi technology has evolved significantly since its introduction in 1997,advancing to Wi-Fi 6 as the latest standard,with Wi-Fi 7 currently under development.Despite these advancements,integrating machine learning in... Wi-Fi technology has evolved significantly since its introduction in 1997,advancing to Wi-Fi 6 as the latest standard,with Wi-Fi 7 currently under development.Despite these advancements,integrating machine learning into Wi-Fi networks remains challenging,especially in decentralized environments with multiple access points(mAPs).This paper is a short review that summarizes the potential applications of federated reinforcement learning(FRL)across eight key areas of Wi-Fi functionality,including channel access,link adaptation,beamforming,multi-user transmissions,channel bonding,multi-link operation,spatial reuse,and multi-basic servic set(multi-BSS)coordination.FRL is highlighted as a promising framework for enabling decentralized training and decision-making while preserving data privacy.To illustrate its role in practice,we present a case study on link activation in a multi-link operation(MLO)environment with multiple APs.Through theoretical discussion and simulation results,the study demonstrates how FRL can improve performance and reliability,paving the way for more adaptive and collaborative Wi-Fi networks in the era of Wi-Fi 7 and beyond. 展开更多
关键词 Artificial intelligence reinforcement learning channels selection wireless local area networks 802.11ax 802.11be WI-FI
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Niche vs.habitat:Insights of aging microplastics and wetland types on bacterial community assembly
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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
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Influence of high-frequency vibration-absorbing fasteners on suppressing localized rail bending modal vibration
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作者 Zhecheng Tao Dadi Li +7 位作者 Lai Wei Chaozhi Ma Sheng Qu Caihong Huang Hao Gao Bin Zhu Huanyun Dai Yunguang Ye 《Railway Engineering Science》 2026年第1期159-183,共25页
Since the view that the localized rail third-order bending mode can cause high-order polygonization(mainly 18-23)of high-speed train wheels was put forward in 2017,many scholars have attempted to link a connection bet... Since the view that the localized rail third-order bending mode can cause high-order polygonization(mainly 18-23)of high-speed train wheels was put forward in 2017,many scholars have attempted to link a connection between the localized rail bending modes and wheel polygonization phenomenon and polygonal wheel passing frequency.This paper first establishes a flexible track model considering the structural and parametric characteristics of fasteners,verifies the model by using vehicle tracking test data,then investigates the influence of fastener parameter matching on the localized rail bending modes,and obtains the following conclusions:(1)There is nearly a 1:1 mapping relationship between the localized rail bending modal frequency and polygonal wheel passing(PWP)frequency,which supports that the localized rail bending mode is one of the causes of wheel polygonization.(2)The iron plate of the fastener system plays a role of dynamic vibration absorber in the vehicle-rail coupled system,and the fastener parameters significantly influence the localized rail bending modal vibration.Finally,this paper proposes a design principle of a high-frequency vibration-absorbing fastener,which provides a feasible solution to mitigate the localized rail bending modal vibration and high-order wheel polygonization.Meanwhile,it points out that this measure may induce other high-frequency vibration problems,e.g.,aggravating modal vibration above 800 Hz.Further,this paper proposes a concept of differentiated arrangement of fasteners,suggesting that different high-frequency vibration-absorbing fasteners be installed in different sections of the whole line to make the localized rail bending modal frequency of the whole line disordered,thus disrupting and further mitigating the development of the wheel polygonization. 展开更多
关键词 Localized rail bending mode High-speed train Fastener system Dynamic vibration absorber Parameter investigation
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