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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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Detection of tracheal branching with computerized tomography:The relationship between the angles and age-gender 被引量:1
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作者 Şevket Kahraman Mesut Furkan Yazar +2 位作者 Hüseyin Aydemir Mecit Kantarci Sonay Aydin 《World Journal of Radiology》 2023年第4期118-126,共9页
BACKGROUND The data obtained on the anatomical knowledge of the tracheobronchial system can be used for diagnosis,treatment and interventional interventions in areas such as anesthesia,thoracic surgery,pulmonary physi... BACKGROUND The data obtained on the anatomical knowledge of the tracheobronchial system can be used for diagnosis,treatment and interventional interventions in areas such as anesthesia,thoracic surgery,pulmonary physiology.AIM To determine the tracheobronchial branching angles in pediatric and adult populations by using the multislice computed tomography(CT)and minimum intensity projection(MinIP)technique,which is a non-invasive method.METHODS Our study was carried out retrospectively.Patients who underwent contrast and non-contrast CT examination,whose anatomically and pathophysiologically good tracheobronchial system and lung parenchyma images were obtained,were included in the study.Measurements were made in the coronal plane of the lung parenchyma.In the coronal plane,right main bronchus-left main bronchus angle,right upper lobe bronchus-intermedius bronchus angle,right middle lobe bronchus-right lower lobe bronchus angle,left upper lobe bronchus-left lower lobe bronchus angle were measured.RESULTS The study population consisted of 1511 patients,753 pediatric(mean age:13.4±4.3;range:1-18 years)and 758 adults(mean age:54.3±17.3;range:19-94 years).In our study,tracheal bifurcation angle was found to be 73.3°±13.7°(59.6°-87°)in the whole population.In the pediatric group,the right-left main coronal level was found to be higher in boys compared to girls(74.6°±12.9°vs 71.2°±13.9°,P=0.001).In the adult group,the right-left main coronal level was found to be lower in males compared to females(71.9°±12.9°vs 75.8°±14.7°,P<0.001).CONCLUSIONS Our study,with the number of 1511 patients,is the first study in the literature with the largest number of patient populations including pediatric and adult demographic data,measuring the angle values of the tracheobronchial system using multislice CT and MinIP technique.Study data will not only be a guide during invasive procedures,but it can also guide studies to be done with imaging methods. 展开更多
关键词 Tracheobronchial branching angles Subcarinal angle Multislice computerized tomography Minimum intensity projection technique
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Anchorage properties at the interface between soil and roots with branches 被引量:8
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作者 Xiaodong Ji Lihua Chen Ao Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第1期83-93,共11页
Roots play an important role in stabilizing and strengthening soil. This article aims to study the mechanical properties of the interface between soil and roots with branches, using the pullout test method in the labo... Roots play an important role in stabilizing and strengthening soil. This article aims to study the mechanical properties of the interface between soil and roots with branches, using the pullout test method in the laboratory. The mechanical properties of the soil-root with branches interface is determined through the pullout-force and root-slippage curve (F-S curve). The results of investigating 24 Pinus tabulaeformis single roots and 55 P. tabulaeformis roots with branches demonstrated three kinds of pullout test failures: breakage failure on branching root, breakage failure on branching node, and pullout failure. The branch angle had a remarkable effect on the failure mode of the roots with branches: the maximum pullout force increased with the sum of the branch diameters and the branch angle. The peak slippage and the initial force had a positive correlation with the sum of the branch diameter. The sig- nificance test of correlation between branch angle and the initial force, however, showed they had no correlation. Branch angle and branch root diameter affect the anchorage properties between root system and soil. Therefore, it is important to investigate the anchorage mechanics of the roots with branches to understand the mechanism of root reinforcement and anchorage. 展开更多
关键词 Root-soil interface mechanics Pullout test method Root branches branch angle
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Branching angles in the modulation of plant architecture:Molecular mechanisms,dynamic regulation,and evolution 被引量:1
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作者 Chen Yun Wanzhuang Ma +1 位作者 Jun Feng Lanxin Li 《Plant Communications》 2025年第4期68-82,共15页
Plants develop branches to expand areas for assimilation and reproduction.Branching angles coordinate with branching types,creating diverse plant shapes that are adapted to various environments.Two types of branching ... Plants develop branches to expand areas for assimilation and reproduction.Branching angles coordinate with branching types,creating diverse plant shapes that are adapted to various environments.Two types of branching angle—the angle between shoots and the angle in relation to gravity or the gravitropic set-point angle(GSA)along shoots—determine the spacing between shoots and the shape of the aboveground plant parts.However,it remains unclear how these branching angles are modulated throughout shoot development and how they interact with other factors that contribute to plant architecture.In this review,we systematically focus on the molecular mechanisms that regulate branching angles across various spe-cies,including gravitropism,anti-gravitropic offset,phototropism,and other regulatory factors,which collectively highlight comprehensive mechanisms centered on auxin.We also discuss the dynamics of branching angles during development and their relationships with branching number,stress resistance,and crop yield.Finally,we provide an evolutionary perspective on the conserved role of auxin in the regu-lation of branching angles. 展开更多
关键词 branching angles plant architecture AUXIN TROPISMS anti-gravitropic offset EVOLUTION
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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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ZmTCP23 regulates leaf angle and tassel branch angle formation in maize by modulating LG1 expression and abscisic acid catabolism
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作者 Panpan Yang Kailin Zeng +8 位作者 Hu Hailing Wang Xiaoting Zhuang Juntao Wu Zerong Chen Zhuojun Zhong Yongming Liu Dexin Kong Haiyang Wang Yuting Liu 《Journal of Integrative Plant Biology》 2025年第10期2744-2759,共16页
Leaf angle(LA)and tassel branch angle(TBA)are two important agronomic traits influencing maize plant architecture,thereby affecting its adaptability to high-density planting.Liguleless1(LG1)acts as a key regulator of ... Leaf angle(LA)and tassel branch angle(TBA)are two important agronomic traits influencing maize plant architecture,thereby affecting its adaptability to high-density planting.Liguleless1(LG1)acts as a key regulator of LA and TBA,yet its precise regulatory mechanism remains largely obscure.In this study,we have identified ZmTCP23,a teosinte branched1/CYCLOIDEA/proliferating cell factors(TCP)transcription factor that is highly expressed in tassel and leaf primordia,serving as a pivotal upstream transcriptional regulator of LG1.The functional loss of ZmTCP23 results in a significant reduction in both TBA and LA ranges.Moreover,in vitro and in vivo studies revealed that LG1 directly represses the expression of ZmXERICO1,a gene encoding an inhibitor of abscisic acid(ABA)degradation that can also influence LA and TBA upon overexpression.Additionally,ZmTCP23 physically interacts with the previously identified TBA regulator BAD1,forming a complex that co-activates the expression of LG1 via direct binding to its promoter.This dynamic duo established a positive feedback loop,mutually enhancing each other's expression within the tassels,and consequently influencing TBA.Our findings establish a ZmTCP23-LG1-ZmXERICO1 transcriptional regulatory cascade that orchestrates LA and TBA through influencing ABA content,and provide new targets for the genetic manipulation of LA and TBA for molecular breeding of high-density tolerant maize cultivars. 展开更多
关键词 ABA leaf angle LG1 maize tassel branch angle ZmTCP23
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