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Utilizing quantile regressions to predict vertical distribution of branch size in Larix olgensis Henry:Capturing the differentiated responses of varying branch sizes to stand and tree factors
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作者 Zheng Miao Fengri Li +2 位作者 Xuehan Zhao Yumeng Jiang Lihu Dong 《Forest Ecosystems》 2025年第3期454-471,共18页
Branch size is a crucial characteristic,closely linked to both tree growth and wood quality.A review of existing branch size models reveals various approaches,but the ability to estimate branch diameter and length wit... Branch size is a crucial characteristic,closely linked to both tree growth and wood quality.A review of existing branch size models reveals various approaches,but the ability to estimate branch diameter and length within the same whorl remains underexplored.In this study,a total of 77 trees were sampled from Northeast China to model the vertical distribution of branch diameter and length within each whorl along the crown.Several commonly used functions were taken as the alternative model forms,and the quantile regression method was employed and compared with the classical two-step modeling approach.The analysis incorporated stand,tree,and competition factors,with a particular focus on how these factors influence branches of varying sizes.The modified Weibull function was chosen as the optimal model,due to its excellent performance across all quantiles.Eight quantile regression curves(ranging from 0.20 to 0.85)were combined to predict branch diameter,while seven curves(ranging from 0.20 to 0.80)were used for branch length.The results showed that the quantile regression method outperformed the classical approach at model fitting and validation,likely due to its ability to estimate different rates of change across the entire branch size distribution.Lager branches in each whorl were more sensitive to changes in DBH,crown length(CL),crown ratio(CR)and dominant tree height(H_(dom)),while slenderness(HDR)more effectively influenced small and medium-sized branches.The effect of stand basal area(BAS)was relatively consistent across different branch sizes.The findings indicate that quantile regression is a good way not only a more accurate method for predicting branch size but also a valuable tool for understanding how branch growth responds to stand and tree factors.The models developed in this study are prepared to be further integrated into tree growth and yield simulation system,contributing to the assessment and promotion of wood quality. 展开更多
关键词 branch diameter branch length Quantile regression Crown structure Wood quality
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A naturally occurring 31 bp deletion in TEOSINTE BRANCHED1 causes branched ears in maize
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作者 Ling Ai Ju Qiu +11 位作者 Jiuguang Wang Mengya Qian Tingting Liu Wan Cao Fangyu Xing Hameed Gul Yingyi Zhang Xiangling Gong Jing Li Hong Duan Qianlin Xiao Zhizhai Liu 《Journal of Integrative Agriculture》 2025年第9期3322-3333,共12页
The female inflorescence,or ear,of maize develops no branch meristem(BM),which differs from the male inforescence,or tassel.While the mutations of some well documented genes,such as fea2/3/4 and ramosa1/2/3,can cause ... The female inflorescence,or ear,of maize develops no branch meristem(BM),which differs from the male inforescence,or tassel.While the mutations of some well documented genes,such as fea2/3/4 and ramosa1/2/3,can cause the branched architecture of ears in maize,such mutations also change the normal phenotypic performance of the tassels.In the present study,a natural maize mutant with branched ears,named branched ear1(be1),was characterized.be1 shows several branched ears at the base of the central ear with unchanged architecture of the tassels.Besides,both the branched and central ears of be1 possess regularly arranged kerels.The phenotypic characteristics of be1 differ completely from those reported mutants of fasciated ears or RAMOSA-like ears in maize.An SEM survey at the very early development stage showed that meristems with three protrusions,similar to the BM in tassels,were present during the development of the branched ears in be1.Gene mapping and sequence alignment suggested that TEOSINTE BRANCHED1(TB1)was the candidate gene of BE1.Further verification showed that a be1-specific 31 bp deletion at the downstream of BE1 led to statistically reduced expression of this gene in the immature ear,which serves as the potential causal reason for the branched ears of be1.CRISPR/Cas9-based gene editing downstream of TB1 complemented the phenotypic architecture of branched ears,suggesting that TB1 was the target of BE1,and it was named as Zm TB1be1.The results of the present study implied a novel function of TB1 in female inforescence development,rather than shaping the plant architecture in maize.Meanwhile,further functional dissection of ZmTB1be1might shed new light on TB1,the most famous domestication related gene in maize. 展开更多
关键词 maize(Zea mays L.) branched ear1(be1) TEOSINTE branchED1(TB1) female inflorescence DELETION
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Regulation of tillering and panicle branching in rice and wheat 被引量:1
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作者 Ning Zhang Yuhao Liu +1 位作者 Songtao Gui Yonghong Wang 《Journal of Genetics and Genomics》 2025年第7期869-886,共18页
Branching is a critical aspect of plant architecture that significantly impacts the yield and adaptability of staple cereal crops like rice and wheat.Cereal crops develop tillers during the vegetative stage and panicl... Branching is a critical aspect of plant architecture that significantly impacts the yield and adaptability of staple cereal crops like rice and wheat.Cereal crops develop tillers during the vegetative stage and panicle or spike branches during the reproductive stage,respectively,both of which are significantly impacted by hormones and genetic factors.Tillering and panicle branching are closely interconnected and exhibit high environmental plasticity.Here,we summarize the recent progress in genetic,hormonal,and environmental factors regulation in the branching of rice and wheat.This review not only provides a comprehensive overview of the current knowledge on branching mechanisms in rice and wheat,but also explores the prospects for future research aimed at optimizing crop architecture for enhanced productivity. 展开更多
关键词 RICE WHEAT Crop architecture TILLERING Panicle branching
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Optical Observation of Streamer Branches in a 1 m Rod-Plate Air Gap under Positive Impulse Voltages
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作者 HE Zhaoxia Wu Chuanqi +2 位作者 CHEN Jun WANG Tao HE Hengxin 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2021年第1期107-114,共8页
In this study,based on two CMOS cameras,an orthogonal optical observation platform has been set up for positive streamer branches under 1 m rod-plate air gap.The Monopodia branch and the Dichotomous branch have been p... In this study,based on two CMOS cameras,an orthogonal optical observation platform has been set up for positive streamer branches under 1 m rod-plate air gap.The Monopodia branch and the Dichotomous branch have been proposed for steamer branch classification.The branch length,the branch angle and the optical diameter are statistical obtained and compared for the two branch types under different impulse voltages.The empirical function between the branch length Ls and the inception voltage Ui of the Monopodia branch has been obtained.The distributions of the branch angle and the axial angle of the two types have been given,and the mean optical diameters have been provided.Based on the comparisons,the formation mechanism of the two branch types has been proposed.This experimental result can provide the basic data to the numerical calculation of positive long air gap discharge. 展开更多
关键词 streamer branch orthogonal optical observation streamer inception branch type branch angle optical diameter of streamer branch
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Identification of QTLs for plant height and branching-related traits in cultivated peanut
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作者 Shengzhong Zhang Xiaohui Hu +5 位作者 Feifei Wang Huarong Miao Chu Ye Weiqiang Yang Wen Zhong Jing Chen 《Journal of Integrative Agriculture》 2025年第7期2511-2524,共14页
Plant height(PH),primary lateral branch length(PBL),and branch number(BN)are architectural components impacting peanut pod yield,biomass production,and adaptivity to mechanical harvesting.In this study,a recombinant i... Plant height(PH),primary lateral branch length(PBL),and branch number(BN)are architectural components impacting peanut pod yield,biomass production,and adaptivity to mechanical harvesting.In this study,a recombinant inbred population consisting of 181 individual lines was used to determine genetic controls of PH,PBL,and BN across three environments.Phenotypic data collected from the population demonstrated continuous distributions and transgressive segregation patterns.Broad-sense heritability of PH,PBL,and BN was found to be 0.87,0.88,and 0.92,respectively.Unconditional individual environmental analysis revealed 35 additive QTLs with phenotypic variation explained(PVE)ranging from 4.57 to 21.68%.A two-round meta-analysis resulted in 24consensus and 19 unique QTLs.Five unique QTLs exhibited pleiotropic effects and their genetic bases(pleiotropy or tight linkage)were evaluated.A joint analysis was performed to estimate the QTL by environment interaction(QEI)effects on PH,PBL,and BN,collectively explaining phenotypic variations of 10.80,11.02,and 7.89%,respectively.We identified 3 major and stable QTL regions(uq9-3,uq10-2,and uq16-1)on chromosomes 9,10,and 16,spanning1.43-1.53 Mb genomic regions.Candidate genes involved in phytohormones biosynthesis,signaling,and cell wall development were proposed to regulate these morphological traits.These results provide valuable information for further genetic studies and the development of molecular markers applicable to peanut architecture improvement. 展开更多
关键词 PEANUT plant height branching QTL mapping candidate gene
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Developing branch diameter and length models for the planted Larix kaempferi from different latitude regions in China
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作者 Yiwen Tong Dongsheng Chen +2 位作者 Huilin Gao Yunhui Xie Jiateng Liu 《Journal of Forestry Research》 2025年第5期160-174,共15页
Branch length and branch diameter are important characteristics that determine wood quality and yield.Development of static branch length and diameter models by incorporating individual tree variables,site quality and... Branch length and branch diameter are important characteristics that determine wood quality and yield.Development of static branch length and diameter models by incorporating individual tree variables,site quality and competition have been widely studied,while the climate effect has rarely been reported.In this study,mixed-effects climate-sensitive branch length and diameter models were developed based on 228 sample trees of Larix kaempferi from three latitude regions in China(approximate 42°N in Liaoning Province,33°N in Gansu Province,and 30°N in Hubei Province).Results revealed that diameter at breast height,and crown ratio,sum of the basal areas of trees larger than the subject trees,dominant tree height,mean warmest month temperature,and summer precipitation substantially improved branch length model.Diameter at breast height,and crown ratio,ratio of the sum of DBH in sample plot to the subject tree,dominant tree height,mean warmest month temperature,and spring precipitation significantly improved branch diameter model.Compared with base model,mean square error reduction of mixed-effects branch length and diameter models were 32.9%and 44.1%,respectively.The relative contributions of covariates to branch length model were tree size(59.1%),site quality(25.7%),competition(13.5%),and climate(1.7%),and branch diameter model were tree size(57.0%),competition(21.9%),site quality(18.3%),and climate(2.8%).Relative contributions of covariates on branch length and diameter models from different latitude regions were different.Effects of competition on branch length model in Liaoning and Hubei were larger than climate,whereas climate in Gansu was larger than competition.As for branch diameter model,competition in Liaoning was larger than site quality,whereas site quality in Hubei and Gansu was larger than competition.The present study strengthened the importance of considering climate variables in developing branch length and diameter model.It is desirable to disentangle the different sources of variations in affecting branch length and diameter from different latitude regions to reduce the uncertainty in predicting branch characteristics under the condition of climate changing. 展开更多
关键词 branch characteristic model Latitude regions CLIMATE Competition index Larix kaempferi
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Mechanochromic Branched Polyethylenes Synthesized through Ring-opening Metathesis Terpolymerization
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作者 Yan-Lin Zong Yi-Xin Zhang Zhong-Bao Jian 《Chinese Journal of Polymer Science》 2025年第7期1181-1189,共9页
Mechanochromic polyolefins represent a novel class of functionalized polyolefins,which still remains significant challenges.Pd(II)-catalyzed coordination-insertion copolymerization is a feasible method for achieving t... Mechanochromic polyolefins represent a novel class of functionalized polyolefins,which still remains significant challenges.Pd(II)-catalyzed coordination-insertion copolymerization is a feasible method for achieving this kind of polymers,yet with linear microstructures.Ringopening metathesis polymerization(ROMP)offers another promising avenue for affording functionalized polyolefins.This method exhibits high polar group tolerance and the ability to precisely regulate polymer branches.In this study,we report the method for producing mechanochromic branched polyethylenes via ROMP.By employing the terpolymerization of a well-designed monomer containing the mechanochromic group,NB-ABF,with cyclooctene(COE)and long-chain 5-hexylcyclooctene(COE-C6),following by hydrogenation process,we synthesized a range of functionalized branched polyethylenes characterized by varied branching density and polar monomer incorporation.These polymers bear a structural resemblance to functionalized ethylene-octene copolymers.After crosslinking,mechanochromophores are generated,and mechanochromism is achieved in uniaxial tensile testing.A comprehensive assessment reveals that both the incorporation of polar monomers and variations in branching density significantly influence their mechanical properties.Notably,upon stretching,these materials display pronounced visible color change,confirming the successful development of mechanochromic branched polyethylenes. 展开更多
关键词 Ring-opening metathesis polymerization POLYOLEFIN Functionalized branched polyethylene Mechanochromism
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An Image Manipulation Localization Method Based on Dual-Branch Hybrid Convolution
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作者 Chengliang Yan Lei Zhang Minhui Chang 《Journal of Electronic Research and Application》 2025年第5期172-184,共13页
In existing image manipulation localization methods,the receptive field of standard convolution is limited,and during feature transfer,it is easy to lose high-frequency information about traces of manipulation.In addi... In existing image manipulation localization methods,the receptive field of standard convolution is limited,and during feature transfer,it is easy to lose high-frequency information about traces of manipulation.In addition,during feature fusion,the use of fixed sampling kernels makes it difficult to focus on local changes in features,leading to limited localization accuracy.This paper proposes an image manipulation localization method based on dual-branch hybrid convolution.First,a dual-branch hybrid convolution module is designed to expand the receptive field of the model to enhance the feature extraction ability of contextual semantic information,while also enabling the model to focus more on the high-frequency detail features of manipulation traces while localizing the manipulated area.Second,a multiscale content-aware feature fusion module is used to dynamically generate adaptive sampling kernels for each position in the feature map,enabling the model to focus more on the details of local features while locating the manipulated area.Experimental results on multiple datasets show that this method not only effectively improves the accuracy of image manipulation localization but also enhances the robustness of the model. 展开更多
关键词 Image manipulation localization Content awareness Dual branch Hybrid convolution U-Net
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Research on the Current Situation and Quality Improvement Strategy for University Student Party Branch Construction
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作者 Fengqi Zhao 《Journal of Contemporary Educational Research》 2025年第1期39-43,共5页
University student Party branches serve as the Party’s grassroots organizations within universities and act as a bridge and link between the Party and students.Therefore,it is essential to strengthen the development ... University student Party branches serve as the Party’s grassroots organizations within universities and act as a bridge and link between the Party and students.Therefore,it is essential to strengthen the development of student Party branches and enhance the effectiveness of student Party member education and training.This paper summarizes and analyzes the issues in the construction of student Party branches in universities and explores strategies for improving their quality,aiming to provide a reference for relevant personnel. 展开更多
关键词 UNIVERSITY Student Party branch Quality improvement STRATEGY
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CURRENTS OF COOPERATION With 89 years of legacy,BOC Singapore Branch continues to drive China-Singapore ties while deepening engagement across ASEAN
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作者 Li Xiaolin 《China Report ASEAN》 2025年第8期62-63,共2页
In Chinese tradition,the term“耄耋”(Mào Dié)refers to those in their nineties,a stage of life associated with wisdom and longevity.As the Bank of China Singapore Branch(BOCSG)approaches its 90th anniversar... In Chinese tradition,the term“耄耋”(Mào Dié)refers to those in their nineties,a stage of life associated with wisdom and longevity.As the Bank of China Singapore Branch(BOCSG)approaches its 90th anniversary,this expression captures the spirit of an institution that has stood the test of time.Since its establishment in Singapore in 1936,the BOCSG has maintained a strong and enduring presence not only in Singapore but across Southeast Asia,serving as a bridge between China and Singapore,and more broadly,between China and the ASEAN region.Its continued growth has been underpinned by the mutual prosperity of both economies and the strength of their longstanding and harmonious ties. 展开更多
关键词 anniversary wisdom longevity ASEAN engagement LEGACY Bank China Singapore branch COOPERATION China Singapore ties
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Evaluating tree branch angle measurements of European beech using terrestrial laser scanning
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作者 Xi Peng Kim Calders +1 位作者 Louise Terryn Hans Verbeeck 《Forest Ecosystems》 2025年第2期220-230,共11页
Branch angles are an important plant morphological trait affecting light interception within forest canopies.However,studies on branch angles have been limited due to the time-consuming nature of manual measurements u... Branch angles are an important plant morphological trait affecting light interception within forest canopies.However,studies on branch angles have been limited due to the time-consuming nature of manual measurements using a protractor.Terrestrial laser scanning(TLS),however,provides new opportunities to measure branch angles more efficiently.Despite this potential,studies validating branch angle measurements from TLS have been limited.Here,our aim is to evaluate both manual and automatic branch angle measurements of European beech from TLS data using traditional field-measurements with a protractor as a reference.We evaluated the accuracy of branch angle measurements based on four automated algorithms(aRchiQSM,TreeQSM,Laplacian,SemanticLaplacian)from TLS data.Additionally,we assessed different ways of manual branch angle measurements in the field.Our study was based on a dataset comprising 124 branch angles measured from six European beech in a European deciduous forest.Our results show that manual branch angle measurements from TLS data are in high agreement with the reference(root-mean-squared error,RMSE:[3.57°-4.18°],concordance correlation coefficient,CCC:[0.950.97])across different branch length positions.Automated algorithms also are in high agreement with the reference although RMSE is approximately twice as large compared to manual branch angle measurements from TLS(RMSE:[9.29°-10.55°],CCC:[0.830.86])with manual leaf points removal.When applying the automatic wood-leaf separation algorithm,the performance of the four methods declined significantly,with only approximately 20 branch angles successfully identified.Moreover,it is important to note that there is no influence of the measurement position(branch surface versus center)for branch angle measurements.However,for curved branches,the selection of branch measurement length significantly impacts the branch angle measurement.This study provides a comprehensive understanding of branch angle measurements in forests.We show that automated measurement methods based on TLS data of branch angles are a valuable tool to quantify branch angles at larger scales. 展开更多
关键词 branch angle Measurement methods Quantitative structure models LAPLACIAN Semantic-laplacian Terrestrial laser scanning
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Tailoring End-Use Properties of Polypropylene through a Combination of Specific Nucleation and Long-Chain Branching
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作者 Lenka Gajzlerova Jana Navratilova +4 位作者 Martina Polaskova Lubomir Benicek David Jaska Sona Zenzingerova Roman Cermak 《Chinese Journal of Polymer Science》 2025年第1期101-109,I0009,共10页
The present study presents an assessment of the interrelations between long-chain branching,specific nucleation,and end-use properties of polypropylene blends:blends of linear polypropylene(L-PP)and long-chain branche... The present study presents an assessment of the interrelations between long-chain branching,specific nucleation,and end-use properties of polypropylene blends:blends of linear polypropylene(L-PP)and long-chain branched polypropylene(LCB-PP)modified by a specificβ-nucleating agent(NA).Specimens with various LCB-PP compositions with and without NA were prepared under complex flow fields by injection molding.Wide-angle X-ray scattering was employed to capture the X-ray patterns of both the skin and core of the specimens,determining the overall crystallinity and amounts of individual polymorphs.The increasing content of LCB-PP andγ-phase,at the same time,in the blends is reflected in both increasing crystallinity and improved mechanical properties,namely,yield stress and Young’s modulus.On the other hand,the composition of the blends had no significant effect on the impact strength,except for nucleated L-PP.It has been demonstrated that adding a relatively small amount of LCB-PP is sufficient to modify the mechanical properties of linear polypropylene.Even a very small amount of LCB-PP in the L-PP suppressed the effectiveness of NA. 展开更多
关键词 Polymeric blend Long-chain branched polypropylene Polymorphism Mechanical property
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Banking on Culture and Connections A glimpse into Bank of China Singapore Branch’s effort to promote cultural exchange between China and Singapore
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《China Report ASEAN》 2025年第12期48-49,共2页
As part of its longstanding commitment to advancing cultural exchange between China and Singapore,Bank of China Singapore Branch is supporting a major cultural initiative-the exhibition“Journeys through Mountains and... As part of its longstanding commitment to advancing cultural exchange between China and Singapore,Bank of China Singapore Branch is supporting a major cultural initiative-the exhibition“Journeys through Mountains and Rivers in Ming and Qing Painting”presented by the China Culture Centre in Singapore from November 1,2025,to January 18,2026. 展开更多
关键词 China Culture Centre cultural exchange Ming Qing painting Singapore branch Bank China
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Acceleration of Form Ⅱ-Ⅰ Transition in Polybutene-1 by H-shape Long-chain Branching: Critical Role of 1,9-Decadiene as Branching Agent and Synergy with Comonomer
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作者 Hui-Ping Yu Jin-Yong Dong 《Chinese Journal of Polymer Science》 2025年第12期2362-2372,I0014,共12页
Polybutene-1(PB-1) is a semi-crystalline polymer with excellent mechanical properties. However, its practical application is significantly hindered by the slow Form Ⅱ-Ⅰ transition, which can take up to several days ... Polybutene-1(PB-1) is a semi-crystalline polymer with excellent mechanical properties. However, its practical application is significantly hindered by the slow Form Ⅱ-Ⅰ transition, which can take up to several days to complete. While prior research established that long-chain branching(LCB) structures synthesized via ω-alkenylmethyldichlorosilane copolymerization-hydrolysis(ACH) chemistry markedly accelerate this transition, this work demonstrates that H-shaped LCB structures constructed through copolymerization with 1,9-decadiene exhibit the capability to facilitate Form Ⅱ-Ⅰ transition in most systems evaluated herein. However, low branching efficiency concurrently generates extended alkyl pendant chains, which impose pronounced steric-hindrance-driven suppression on the transition kinetics, thereby substantially diminishing the net acceleration effect of the LCB structures, even resulting in a net retardation effect in certain systems. Notably, a significant synergistic acceleration effect emerged between the H-shaped LCB structures and propylene comonomer units. These findings confirm that the H-shaped LCB structures play a role in promoting the Form II-I transformation process, which is independent of the synthetic pathways, thereby providing more strategies for addressing the long-standing processing problems of PB-1. 展开更多
关键词 POLYBUTENE-1 H-shape long-chain branching Propylene comonomer 1 9-Decadiene FormⅡ-Ⅰtransition
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Correlations between inflammatory biomarkers in peripheral blood and branch retinal vein occlusion
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作者 Xiao-Juan Lai Song-Yue Yang +2 位作者 Chun-Yan Lei Rui-Han Xiao Mei-Xia Zhang 《International Journal of Ophthalmology(English edition)》 2025年第10期1908-1913,共6页
AIM:To investigate the possible relationship between inflammatory biomarkers in the peripheral blood of patients with branch retinal vein occlusion(BRVO).METHODS:A total of 63 BRVO patients were enrolled in this cross... AIM:To investigate the possible relationship between inflammatory biomarkers in the peripheral blood of patients with branch retinal vein occlusion(BRVO).METHODS:A total of 63 BRVO patients were enrolled in this cross-sectional observational study.Meanwhile,63 age-and gender-matched cataract patients were included as controls.Complete blood count and biochemical tests were performed,and inflammatory biomarkers including platelet to lymphocyte ratio(PLR),red blood cell distribution width to albumin ratio(RAR),neutrophil to lymphocyte ratio(NLR),systemic immune inflammation index(SII),and monocyte to high density lipoprotein cholesterol ratio(MHR)were compared between the two groups.RESULTS:There were no significant differences between the two groups in terms of age,sex,and prevalence of diabetes mellitus.Compared with the controls,patients with BRVO had a higher prevalence of hypertension and higher body mass index(BMI).Red blood cell distribution width(RDW),triglycerides,MHR,NLR,and RAR were elevated,whereas lymphocyte count and high-density lipoprotein were decreased in the BRVO group.Multivariate logistic regression analysis revealed that NLR(adjusted OR=1.686,95%CI 1.075-2.646),RAR(adjusted OR=8.930,95%CI 1.911-41.730),and body mass index(BMI;adjusted OR=1.174,95%CI 1.010-1.365)were significantly associated with the risk of BRVO.In the receiver operating characteristic analysis,the area under the curve for NLR,RAR,and BMI were 0.602,0.630,and 0.603,respectively.The sensitivity and specificity were 61.9%and 60.3%,38.1%and 82.5%,and 61.9%and 57.1%,respectively.CONCLUSION:Peripheral blood inflammatory biomarkers are elevated in BRVO patients,suggesting systemic inflammation involvement.NLR,RAR,and BMI are positively correlated with BRVO.Monitoring NLR and RAR and strict weight control may be beneficial for the prevention and treatment of BRVO. 展开更多
关键词 branch retinal vein occlusion peripheral blood BIOMARKER
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Effect of Long Chain Branches of High Melt Strength Polypropylene on Its Supercritical CO_(2)Foaming Behavior
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作者 Ruiheng He Zilong Lv +3 位作者 Jichun Jiang Fangfei Xing Tao Liu Shicheng Zhao 《Carbon and Hydrogen》 2025年第2期214-225,共12页
Polypropylene(PP)has a relatively low melt strength due to its linear structure,which seriously limits its supercritical CO_(2)foaming performance.Introducing long-chain branches(LCBs)via grafting can significantly en... Polypropylene(PP)has a relatively low melt strength due to its linear structure,which seriously limits its supercritical CO_(2)foaming performance.Introducing long-chain branches(LCBs)via grafting can significantly enhance its melt strength.However,the relationship between the LCB level of high melt strength polypropylene(HMSPP)and its foaming behavior remains unclear.In this study,a series of HMSPP with different LCB levels was prepared using vinyl polydimethylsiloxane(VS)of varying viscosities as grafting monomers to investigate this relationship.Rheological analysis showed that the increase in viscosity of VS led to higher LCB levels in HMSPP.The melt strength of HMSPP increases with the increase of LCB levels,reaching up to 0.62 N,which is 13 times higher than that of the raw material.Supercritical CO_(2)foaming results revealed that the expansion ratio of HMSPP first increased and then decreased with the increase of melt strength,reaching a maximum of 39.4 times.Combining experiments with simulations,the influence of LCB levels on the dissolution and diffusion behavior of CO_(2)in HMSPP was clarified.This study deepens the understanding of the relationship between LCB and the foaming behavior of HMSPP,providing valuable insights for designing HMSPP with optimized foaming properties. 展开更多
关键词 high melt strength polypropylene long-chain branches supercritica CO_(2)foaming
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High-performance Flow Chemistry Platform for Scalable Continuous Synthesis of Branched Block Copolymers with Precise Chain Structures
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作者 Bang-Bang Wang Zhuang Zhang +3 位作者 Jing-Tao Wang Li Pan Yue-Sheng Li Dong-Po Song 《Chinese Journal of Polymer Science》 2025年第3期457-467,共11页
Cutting-edge research has primarily focused on flow synthesis of linear block copolymers,lacking the ability for manipulating chain architectures for more extensive applications.Herein,we develop a flow chemistry plat... Cutting-edge research has primarily focused on flow synthesis of linear block copolymers,lacking the ability for manipulating chain architectures for more extensive applications.Herein,we develop a flow chemistry platform for the continuous microflow synthesis of bottlebrush block copolymers(BBCPs)using a grafting-through method.This involves performing ring-opening metathesis polymerization(ROMP)of two different macromonomers within two microfluidic reactors connected in series.The microflow environment allows for complete monomer conversion within a few tens of seconds,benefiting from the superior mixing efficiency achieved in Z-shaped channels as indicated by both theoretical simulations and experimental results.Consequently,a library of well-defined BBCPs of up to 528 distinct samples can be produced within one day through automation of the continuous procedure,while keeping precise control on degree of polymerization(DP<4)and polydispersity indices(PDI<1.2).The synthetic method is generally applicable to different macromonomers with different compositions and contour lengths,yielding libraries of branched block copolymers with great diversity in physiochemical properties and chain architectures.This work presents a powerful platform for high-throughput production of branched copolymers,significantly lowering the costs of the materials for real applications. 展开更多
关键词 Continuous flow synthesis Ring opening metathesis polymerization branched copolymer
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Corrigendum:“Search for Binarity in Asymptotic Giant Branch Stars Utilizing the Future Chinese Space Station Telescope”(2025,RAA,25,085003)
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作者 Zhi-Meng Li Yong Zhang 《Research in Astronomy and Astrophysics》 2025年第9期246-246,共1页
1.The diamond symbol(■)should be labeled as[R UMa](was incorrectly labeled as[V Eri]);2.The hexagon symbol(■)should be labeled as[V Eri](was incorrectly labeled as[R UMa]).
关键词 binarity Chinese space station telescope asymptotic giant branch stars
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Dual-branch spatial-temporal decoupled fusion transformer for safety action recognition in smart grid substation
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作者 HAO Yu ZHENG Hao +3 位作者 WANG Tongwen WANG Yu SUN Wei ZHANG Shujuan 《Optoelectronics Letters》 2025年第8期507-512,共6页
Smart grid substation operations often take place in hazardous environments and pose significant threats to the safety of power personnel.Relying solely on manual supervision can lead to inadequate oversight.In respon... Smart grid substation operations often take place in hazardous environments and pose significant threats to the safety of power personnel.Relying solely on manual supervision can lead to inadequate oversight.In response to the demand for technology to identify improper operations in substation work scenarios,this paper proposes a substation safety action recognition technology to avoid the misoperation and enhance the safety management.In general,this paper utilizes a dual-branch transformer network to extract spatial and temporal information from the video dataset of operational behaviors in complex substation environments.Firstly,in order to capture the spatial-temporal correlation of people's behaviors in smart grid substation,we devise a sparse attention module and a segmented linear attention module that are embedded into spatial branch transformer and temporal branch transformer respectively.To avoid the redundancy of spatial and temporal information,we fuse the temporal and spatial features using a tensor decomposition fusion module by a decoupled manner.Experimental results indicate that our proposed method accurately detects improper operational behaviors in substation work scenarios,outperforming other existing methods in terms of detection and recognition accuracy. 展开更多
关键词 identify improper operations manual supervision avoid misoperation spatial temporal substation safety action recognition technology dual branch decoupled fusion enhance safety managementin
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Structural Parameters of Branched Polymers:Incorporation of Kinetic Monte Carlo Simulation with Adjacency Matrix
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作者 Xin-Xin Zhao Jiang-Tao Li +1 位作者 Fang Gu Hai-Jun Wang 《Chinese Journal of Chemical Physics》 2025年第6期807-818,I0011-I0014,I0238,共17页
We present an incorporation of the kinetic Monte Carlo(kMC)simulation with the adjacency matrix(AM)method to investigate structural parameters of randomly branched polymers.The AMs of branched polymers are obtained by... We present an incorporation of the kinetic Monte Carlo(kMC)simulation with the adjacency matrix(AM)method to investigate structural parameters of randomly branched polymers.The AMs of branched polymers are obtained by the growth generation model,which is employed in the kMC simulation based on Gillespie’s algorithm.Of particular interest is the effect of the branched units on the relevant structural parameters.As an application in randomly hyperbranched polymers formed by AB_(2)type of monomers,average maximum span length,average length of sub-chains,number distribution of branched units,and meansquare radius of gyration are calculated.It is shown that the branched units can give rise to a significant effect on these physical quantities,whereby such a structure-property relationship can be employed to optimize reaction conditions and implement material designs. 展开更多
关键词 Kinetic Monte Carlo simulation Adjacency matrix Number distribution of branched points Mean-square radius of gyration Maximum span length
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