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Relationship between angle kappa,angle alpha and objective visual quality in patients with multifocal intraocular lens
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作者 Zhu Chaojie Long Tan +2 位作者 Ma Ting Yan Jie Wang Rui 《国际眼科杂志》 2025年第9期1399-1405,共7页
AIM:To investigate how angles kappa and alpha affect postoperative visual quality in patients with multifocal intraocular lens(mIOLs)implantation.METHODS:Retrospective cases series.A total of 46 patients(46 eyes)who u... AIM:To investigate how angles kappa and alpha affect postoperative visual quality in patients with multifocal intraocular lens(mIOLs)implantation.METHODS:Retrospective cases series.A total of 46 patients(46 eyes)who underwent phacoemulsification were subsumed.The correlation between Preoperative angles kappa and alpha,wave-front aberrations and objective visual quality of cornea,internal,and total eye after surgery were analyzed using iTrace.RESULTS:The magnitude of angle kappa was negatively correlated with internal and total modulation transfer function(MTF)at 3 mm;the magnitude of angle kappa was positively correlated with astigmatism,trefoil,higher-order aberrations(HOAs)of both internal and total eye at 3 mm.The magnitude of angle alpha was negatively correlated with total MTF and total Strehl ratio at 3 mm.The magnitude of angle alpha was positively correlated with corneal coma at 5 mm,internal astigmatism at both 3 mm and 5 mm,and total spherical aberration(SA)at 3 mm.Multivariate linear regression analysis showed that,among candidate independent variables(kappa,alpha,astigmatism,SA,coma,trefoil,and HOAs),astigmatism is the only independent factor for altering corneal MTF at 3 mm and 5 mm;astigmatism and HOAs emerged as independent factors for altering internal MTF at 3 mm and 5 mm,and total MTF at 3 mm;astigmatism,SA and HOAs emerged as independent factors for altering total MTF at 5 mm.CONCLUSION:With greater preoperative angle kappa or angle alpha,patients who accept mIOL implantation tend to have larger internal astigmatism and HOAs,which resulting in poor visual quality,especially those with small pupil size. 展开更多
关键词 angle kappa angle alpha modulation transfer function CATARACT Strehl ratio
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Alpha and Kappa angle on postoperative visual quality in cataract surgery
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作者 Xiao-Na Chen Ying-Yue Xiong +2 位作者 Jia Wei Bin Luo Ya-Li Gao 《International Journal of Ophthalmology(English edition)》 2025年第6期1023-1031,共9页
AIM:To explore the effect of Alpha angle and Kappa angle before multifocal intraocular lenses(MIOLs)implantation on postoperative visual quality of patients.METHODS:Before and 3mo after cataract surgery,Alpha angle an... AIM:To explore the effect of Alpha angle and Kappa angle before multifocal intraocular lenses(MIOLs)implantation on postoperative visual quality of patients.METHODS:Before and 3mo after cataract surgery,Alpha angle and Kappa angle were collected using IOL Master 700,iTrace,and Pentacam for clinical observation.Postoperative visual quality indicators,including high-order aberrations(HOA),modulation transfer function(MTF)and point spread function(PSF),were collected using iTrace.multiple linear regression analysis was used to analyze the correlation of the Kappa angle and the Alpha angle with age,axial length(AL),anterior chamber depth(ACD),keratometry(K),lens thickness(LT)and corneal white to white distance(WTW).Pearson correlation coefficient was used to analyze the correlation between Alpha angle and Kappa angle;Bland Altman analysis was used to evaluate the consistency of pairwise detection results of three instruments.RESULTS:The Alpha angle was modeled as Alpha=2.230+0.003×age-0.036×AL-0.025×K-0.058×WTW and the Kappa angle was modeled as Kappa=0.685+0.003×age-0.013×K-0.061×WTW.The correlation between the total Alpha angle and Kappa angle of the three instruments was weakly positive(r=0.291,P=0.000).Comparing the measurement of Alpha angle and Kappa angle using three instruments,only IOL Master 700 and iTrace showed good consistency in measuring Kappa angle(P=0.4254).After 3mo of surgery,the Alpha angle and Kappa angle significantly decreased(P=0.011,0.018;P=0.008,0.036).△Kappa=1.136-0.021×AL-0.013×K.Kappa angle could positively predict HOA(β=0.18,P=0.000),MTF(β=0.171,P=0.000),PSF(β=0.088,P=0.000),Alpha angle cannot(P>0.05).CONCLUSION:The patients with older age,flatter K and shorter WTW should be alert to the possibility of larger Alpha angle and Kappa angle.Alpha angle should also consider the factor of AL.When selecting patients with MIOLs implantation,there is no need to consider the Alpha angle.Careful consideration should be given to the Kappa angle,and the preoperative standard of<0.5 mm can refer to△Kappa=1.136-0.021×AL-0.013×K and be appropriately relaxed. 展开更多
关键词 kappa angle alpha angle postoperative visual quality cataract surgery ocular biometric instruments
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Alterations of the vitreous pathology and anterior chamber angle structures following transscleral cyclophotocoagulation
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作者 Xiao-Wei Yu Zhi-Jun Li +4 位作者 Dan-Ting Lin Yan Gao Jia-Xin Tian Zhi-Gang Fan Yan Shi 《International Journal of Ophthalmology(English edition)》 2025年第12期2246-2254,共9页
AIM:To describe the alterations of the vitreous pathology and anterior chamber(AC)angle structures following transscleral cyclophotocoagulation(TSCP)and better understand the mechanism of post-laser intraocular pressu... AIM:To describe the alterations of the vitreous pathology and anterior chamber(AC)angle structures following transscleral cyclophotocoagulation(TSCP)and better understand the mechanism of post-laser intraocular pressure(IOP)reduction in angle-closure glaucoma(ACG).METHODS:Porcine eyes ex vivo and rabbit eyes in vivo were used.In porcine eyes,permeability rates of the anterior vitreous cortex(AVC)and anterior hyaloid membrane(AHM)were assessed using Schirmer’s strips.Permeability rates in the circumlental space were compared with or without TSCP bursts.Fluorescein diffusion times from the vitreous to the AC were compared between eyes with and without TSCP.In rabbit eyes,changes in IOP and AC angle structures under ultrasound biomicroscopy(UBM)were evaluated at intervals of 30min,7d,and 14d after TSCP.Vitreous pathology was examined using scanning electron microscopy(SEM)immediately and 14d after TSCP.RESULTS:In porcine eyes(n=20),the median(range)permeability rates were 10.3(range 9.8–10.8)mm/min for the AVC and 4.3(range 3.9–4.9)mm/min for the AHM(P=0.009).Permeability rates in the circumlental space were 4.2(range 3.8–4.9)mm/min in areas without TSCP,6.2(range 5.7–6.8)mm/min in areas with non-burst TSCP,and 11.3(range 10.9–11.8)mm/min in areas with burst TSCP(P=0.002).The median(range)fluorescein diffusion time was 5(range 3–8)min in eyes undergoing TSCP,whereas it was 40min(range 35–68)in eyes without TSCP(P<0.001).In rabbit eyes(n=20),SEM showed immediate localized damage to the AHM,AVC,and posterior lens zonules in areas subjected to TSCP bursts,and obvious lens zonule loss with cellular infiltration and possible vitreous liquefaction by post-op day 14.Persistent widening of AC angles was noted at postoperative days 7 and 14,although a significant reduction in IOP was only observed at postoperative day 7.CONCLUSION:TSCP-induced damage on the zonules,AHM,and AVC potentially enhances fluid outflow from the vitreous,leading to a widened AC angle and vitreous liquefaction in rabbits.These observations offer insights into mechanisms of TSCP in lowering IOP and pathogenic roles of vitreous in ACG. 展开更多
关键词 vitreous pathology anterior chamber angle structures transscleral cyclophotocoagulation angleclosure glaucoma
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The Role of Dykes in Shaping Stream Junction Angles:A Case Study of the Rangavali River Basin,Northern Maharashtra
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作者 Sandeep B.Bhise Tushar P.Raut +1 位作者 Suchitra S.Pardeshi Sudhakar D.Pardeshi 《International Journal of Geosciences》 2025年第11期850-870,共21页
Dyke swarms frequently act as natural barriers,obstructing or deflecting stream courses.Streams tend to flow along the outcrop ridges of dykes,resulting in acute junction angles.Dykes serve as structural controls by i... Dyke swarms frequently act as natural barriers,obstructing or deflecting stream courses.Streams tend to flow along the outcrop ridges of dykes,resulting in acute junction angles.Dykes serve as structural controls by influencing the orientation of streams.The relationship between stream junction angles and dyke orientation is a significant factor in stream confluences.Terrain plays a crucial role in directing the river’s flow path and shaping its characteristics.This research paper investigates the impact of dyke orientation on stream junction angles through stream hierarchy analysis.The Rangavali River,a left-bank tributary of the Tapi River,flows for a distance of 45.65 km,crossing 21 East-West(E-W)trending dykes within a 215.95 km2 basin,which forms part of the Deccan Traps.To examine the relationship between dyke orientation and stream junction angles,inputs from Google Earth imagery,LISS III im ages,SOI topographical maps,quadrangle maps,and Cartosat DEM were used to delineate the Rangavali basin and extract dyke features.The Rangavali River basin is a sixth-order drainage system that exhibits a superimposed drainage pattern within the Tapi dyke swarm zone.The prominent linear dyke ridges are predominantly aligned in an East-West direction(average angle N81˚),with a dyke density of 0.51 km/km2.The average junction angle of streams within 100 m upstream and downstream of the dyke ridges is 81˚,compared to an av-erage of 78˚in non-dyke areas.The trend of acute junction angles is attributed to the orientation of the dykes and the distance of streams from the parallel-aligned dyke ridges.This study demonstrates that dyke ridges not only redirect stream flow but also control drainage density and network development.The findings have broader implications for watershed management,flood risk as sessment,infrastructure planning,and groundwater exploration in basaltic terrains and contribute significantly to the understanding of fluvial-structural in teractions in volcanic landscapes. 展开更多
关键词 Deccan Traps Tapi Dyke Swarms Google Earth LISS III Cartosat DEM Junction angles SOI Topographical Maps Quadrangle Maps
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功能矫治器对替牙期骨性AngleⅡ1错颌畸形患儿矫治效果的研究
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作者 肖亦芳 杨珍 +1 位作者 廖健强 邓妹 《黑龙江医学》 2025年第15期1798-1801,共4页
目的:观察功能矫治器对骨性AngleⅡ1错颌畸形患儿的矫治效果。方法:选取2022年5—12月广西科技大学第一附属医院口腔门诊收治的18例骨性AngleⅡ1错颌畸形患儿作为研究对象,通过自身对照,使用功能矫治器矫治12个月,对比矫治前后拍摄的头... 目的:观察功能矫治器对骨性AngleⅡ1错颌畸形患儿的矫治效果。方法:选取2022年5—12月广西科技大学第一附属医院口腔门诊收治的18例骨性AngleⅡ1错颌畸形患儿作为研究对象,通过自身对照,使用功能矫治器矫治12个月,对比矫治前后拍摄的头影测量定位侧位片变化,并通过问卷调查分析满意度和患儿口腔“知信行”的变化情况。结果:治疗12个月后,患儿凸面型变为基本直面型,尖、磨牙基本中性关系,测量值SNB、ANB,Wits值、U1-SN、U1-NA、U1-NA距、OJ值减小,U1-L1、Z角、TLL-E距、SPP-SPPW、U-MPW和TB-TPPW增大,差异均有统计学意义(P<0.05),SNA、FH-MP、SN-MP增大、TUL-E线距减小、L1-MP角、L1-NB角、L1-NB距变化,差异均无统计学意义(P>0.05)。矫治满意度100%,可视菌斑检出率明显下降。结论:对骨性AngleⅡ1错颌畸形患儿使用功能矫治器矫治后,面型改善明显,口颌系统整体功能得到改善,青少年患儿及家长满意度高,在矫治过程中养成了较好的口腔卫生习惯。 展开更多
关键词 骨性angleⅡ1 功能矫治器 替牙期
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Topographic factors associated with anterior chamber angle narrowing in patients with keratoconus 被引量:1
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作者 Hamed Soltan-Dehghan Abdollah Farzaneh +2 位作者 Hassan Hashemi Payam Nabovati Mehdi Khabazkhoob 《International Journal of Ophthalmology(English edition)》 2025年第1期67-73,共7页
AIM:To identify topographic determinants of the anterior chamber angle(ACA)in patients with keratoconus(KCN).METHODS:Four hundred and ten eyes of 294 patients with KCN were recruited for this study.First,complete ocul... AIM:To identify topographic determinants of the anterior chamber angle(ACA)in patients with keratoconus(KCN).METHODS:Four hundred and ten eyes of 294 patients with KCN were recruited for this study.First,complete ocular examinations were performed for all patients,including visual acuity measurement,refraction,and slit-lamp biomicroscopy.Then,all participants underwent corneal imaging by the Oculus Pentacam HR.RESULTS:The mean age of the participants was 32.40±8.52y(15-60y)and 69.5%of them were male.The mean ACA was 38.47°±5.75°(range:14.40°to 56.50°)in the whole sample,38.24°±6.00°in males,and 38.98°±5.11°in females(P=0.447).The mean ACA was significantly different among different groups of cone morphology,as patients with nipple cones showed the lowest mean ACA.Moreover,there were statistically significant differences in the mean ACA among different groups of cone locations,with patients having central cones exhibiting the lowest mean ACA(P<0.001).Anterior and posterior Q values were significantly,directly correlated with ACA(anterior Q:r=0.122,P=0.014,posterior Q:r=0.192,P<0.001).CONCLUSION:This study provides critical insights into the risk factors for ACA narrowing in KCN patients,which is essential for planning intraocular surgeries.Patients with nipple and central cones exhibited the most significant ACA narrowing.Additionally,more negative Q-values are associated with increased ACA narrowing,highlighting the need for targeted diagnostic and therapeutic strategies. 展开更多
关键词 KERATOCONUS anterior chamber angle cone morphology cone location
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Unsteady aerodynamic modeling and analysis of aircraft model in multi-DOF coupling maneuvers at high angles of attack with attention mechanism 被引量:1
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作者 Wenzhao DONG Xiaoguang WANG +1 位作者 Dongbo HAN Qi LIN 《Chinese Journal of Aeronautics》 2025年第6期349-361,共13页
Unsteady aerodynamic characteristics at high angles of attack are of great importance to the design and development of advanced fighter aircraft, which are characterized by post-stall maneuverability with multiple Deg... Unsteady aerodynamic characteristics at high angles of attack are of great importance to the design and development of advanced fighter aircraft, which are characterized by post-stall maneuverability with multiple Degrees-of-Freedom(multi-DOF) and complex flow field structure.In this paper, a special kind of cable-driven parallel mechanism is firstly utilized as a new suspension method to conduct unsteady dynamic wind tunnel tests at high angles of attack, thereby providing experimental aerodynamic data. These tests include a wide range of multi-DOF coupled oscillatory motions with various amplitudes and frequencies. Then, for aerodynamic modeling and analysis, a novel data-driven Feature-Level Attention Recurrent neural network(FLAR) is proposed. This model incorporates a specially designed feature-level attention module that focuses on the state variables affecting the aerodynamic coefficients, thereby enhancing the physical interpretability of the aerodynamic model. Subsequently, spin maneuver simulations, using a mathematical model as the baseline, are conducted to validate the effectiveness of the FLAR. Finally, the results on wind tunnel data reveal that the FLAR accurately predicts aerodynamic coefficients, and observations through the visualization of attention scores identify the key state variables that affect the aerodynamic coefficients. It is concluded that the proposed FLAR enhances the interpretability of the aerodynamic model while achieving good prediction accuracy and generalization capability for multi-DOF coupling motion at high angles of attack. 展开更多
关键词 Unsteady aerodynamics Aerodynamic modeling High angle of attack Wind tunnel test Attention mechanism
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Effects of bedding angles on rockburst proneness of layered anisotropic phyllites 被引量:1
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作者 Lei Xu Fengqiang Gong +1 位作者 Jinhao Dai Zhichao He 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4288-4313,共26页
To examine the effect of bedding angle upon burst proneness in terms of energy,phyllites with seven various bedding angles are selected for conventional uniaxial compression and single-cyclic loading eunloading uniaxi... To examine the effect of bedding angle upon burst proneness in terms of energy,phyllites with seven various bedding angles are selected for conventional uniaxial compression and single-cyclic loading eunloading uniaxial compression tests.The ejection and failure during compression process of phyllites are monitored in real-time by high-speed camera system.The results demonstrate that the phyllites with different bedding angles all consistently follow the linear energy storage and dissipation(LESD)law during compression.The ultimate energy storage of phyllites with varying bedding angles can be calculated precisely via using the LESD law.Based on this,four kinds of energy-based rockburst indices are applied to quantitatively assess the burst proneness for phyllites.Combined with the recorded images of high-speed camera system,ejection distance,and mass of rock fragments and powder,the burst proneness for phyllites with various bedding angles is qualitatively evaluated adopting the far-field ejection mass ratio.Next,burst proneness of anisotropic phyllites is assessed quantitatively and qualitatively.It is found that phyllites with bedding angles of 0°,15°,and 90°have a high burst proneness,and that with bedding angle of 30°has a medium burst proneness,whereas the ones with bedding angles of 45°,60°,and 75°have a low burst proneness.Finally,the published experimental data of shale and sandstone specimens with different bedding angles are extracted,and it is preliminarily verified that the bedding angle does not change the LESD law of rocks. 展开更多
关键词 Rock mechanics Bedding angle Rockburst proneness Linear energy storage and dissipation law Residual elastic energy
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Determination of angle of attack and dynamic stall loop in the complex vortical flow of a vertical axis wind turbine 被引量:1
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作者 Wenzhong Shen Tao Xie +2 位作者 Lingpeng Ge Jiamin Yin Zhenye Sun 《Theoretical & Applied Mechanics Letters》 2025年第1期9-16,共8页
To improve the vertical axis wind turbine(VAWT)design,the angle of attack(AOA)and airfoil data must be treated correctly.The present paper develops a method for determining AOA on a VAWT based on computational fluid d... To improve the vertical axis wind turbine(VAWT)design,the angle of attack(AOA)and airfoil data must be treated correctly.The present paper develops a method for determining AOA on a VAWT based on computational fluid dynamics(CFD)analysis.First,a CFD analysis of a two-bladed VAWT equipped with a NACA 0012 airfoil is conducted.The thrust and power coefficients are validated through experiments.Second,the blade force and velocity data at monitoring points are collected.The AOA at different azimuth angles is determined by removing the blade self-induction at the monitoring point.Then,the lift and drag coefficients as a function of AOA are extracted.Results show that this method is independent of the monitoring points selection located at certain distance to the blades and the extracted dynamic stall hysteresis is more precise than the one with the“usual”method without considering the self-induction from bound vortices. 展开更多
关键词 Vertical axis wind turbine Computational fluid dynamics angle of attack Dynamic stall
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Study and application of the influence of inclination angle on the cross-fusion mechanism of high gas thick coal seam 被引量:1
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作者 Pengxiang Zhao Zechen Chang +4 位作者 Shugang Li Risheng Zhuo Yongyong Jia Qiudong Shao Wen Lei 《International Journal of Mining Science and Technology》 2025年第1期69-85,共17页
In this study,to better decide the effect of coal seam dip angle upon the dynamic change of the crossfusion in gas transport and storage areas during the progress of working face in the high gas thick coal seam,a two-... In this study,to better decide the effect of coal seam dip angle upon the dynamic change of the crossfusion in gas transport and storage areas during the progress of working face in the high gas thick coal seam,a two-dimensional physical simulation experiment regarded as the theoretical research was conducted to properly explore the variation law of overburden fracture.The results demonstrated that the boundary of the gas transport zone was located in the region of fracture separation.The boundary of the gas storage area was located in the abrupt penetration zone.Also,according to the information theory,the state of the gas transport and storage areas was determined by the changing trend of the fracture rate and fracture entropy.The mathematical representation model of the dip effect in gas transport and storage areas was established.The criteria upon which the regional location of the gas transport area and gas storage area can be based were put forward.The cross-fusion evolution process of the dip effect in gas transport and storage areas was revealed as well.The research results could provide guidance for realising directional and accurate gas extraction. 展开更多
关键词 Coal seam dip angle Cross fusion High gas thick coal seam Overburden fracture Gas transport and storage areas
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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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Regulation of tiller angle by gravity-sensing genes in rice
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作者 Tao Yin Yao Sun +3 位作者 Yuxin Tai Zixiang Cheng Chuanyin Wu Yi Sui 《The Crop Journal》 2025年第4期1301-1304,共4页
Endodermal cells and starch-accumulating amyloplasts are well-known gravity sensors initiating shoot gravitropism in Arabidopsis thaliana.The transcription factors SHR and SGR1 regulate endodermal cell formation,while... Endodermal cells and starch-accumulating amyloplasts are well-known gravity sensors initiating shoot gravitropism in Arabidopsis thaliana.The transcription factors SHR and SGR1 regulate endodermal cell formation,while PGM has been demonstrated to regulate starch biosynthesis within chloroplasts,which eventually leads to starch accumulation in amyloplasts.However,the molecular mechanisms of gravity sensing in monocot shoots remain largely unexplored.In this study,we investigated the roles of these genes in rice(Oryza sativa),a model monocot,using CRISPR-Cas9 to generate single,double,and higher-order mutants.The rice genome harbors two orthologs each of SHR and SGR and a single ortholog of PGM.Our results revealed that single mutants of OsPGM,but not OsSHR or OsSGR,showed compromised shoot gravitropism.However,double mutants shr1shr2 and sgr1sgr2 displayed wider tiller angles and reduced gravity sensing,suggesting functional redundancy within each gene pair.Higher-order mutants exhibited progressively severe phenotypes,with quintuple mutants almost unresponsive to gravity stimulation.These findings suggest that these genes act additively through distinct but converging pathways in shoot gravitropism regulation.This study provides novel insights into the molecular mechanisms underlying gravity sensing in monocots and offers valuable knowledge for precision breeding to optimize rice architecture. 展开更多
关键词 Shoot gravitropism Gravity sensing Tiller angle RICE CRISPR-Cas9
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Strength and failure characteristics of hard rock containing a single structural plane under varied loading angles : A true triaxial investigation
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作者 XU Huai-sheng LI Shao-jun +3 位作者 XU Ding-ping LIU Xu-feng FENG Guang-liang WANG Zhao-feng 《Journal of Central South University》 2025年第5期1903-1921,共19页
The spatial relationship between structural planes and principal stresses significantly affects the mechanical properties of deep hard rock.This paper examines the effect of the loading angle under true triaxial compr... The spatial relationship between structural planes and principal stresses significantly affects the mechanical properties of deep hard rock.This paper examines the effect of the loading angle under true triaxial compression.While previous studies focused on the angleβbetween the maximum principal stress and the structural plane,the role of angleω,between the intermediate principal stress and the structural plane,is often overlooked.Utilizing artificially prefabricated granite specimens with a single non-penetrating structural plane,we set the loading angleβto range from 0°to 90°across seven groups,and assignedωvalues of 0°and 90°in two separate groups.The results show that the peak strength is negatively correlated withβup to 45°,beyond which it tends to stabilize.The angleωexerts a strengthening effect on the peak strength.Deformation mainly occurs post-peak,with the strain values ε_(1) and ε_(3) reaching levels 2−3 times higher than those in intact rock.The structural plane significantly influences failure mode whenω=0°,while failure localizes near the σ_(3) surface of the specimens whenω=90°.The findings enhance data on structural plane rocks under triaxial compression and inform theoretical research,excavation,and support design of rock structures. 展开更多
关键词 true triaxial compression hard rock structural plane loading angle STRENGTH failure characteristics
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Fixed-time cooperative interception guidance law with angle constraints for multiple flight vehicles
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作者 ZHAO Enjiao DING Xue +1 位作者 ZHANG Ke YUAN Zengyu 《Journal of Systems Engineering and Electronics》 2025年第2期569-579,共11页
This paper presents a fixed-time cooperative gui-dance method with impact angle constraints for multiple flight vehicles (MFV) to address the challenges of intercepting large maneuvering targets with difficulty and lo... This paper presents a fixed-time cooperative gui-dance method with impact angle constraints for multiple flight vehicles (MFV) to address the challenges of intercepting large maneuvering targets with difficulty and low precision. A coopera-tive guidance model is proposed, transforming the cooperative interception problem into a consensus problem based on the remaining flight time of the flight vehicles. First, the impact angle constraint is converted into the line of sight (LOS) angle con-straint, and a new fixed-time convergent non-singular terminal sliding surface is introduced, which resolves the singularity issue of the traditional sliding surfaces. With this approach, LOS angle rate and normal overloads can converge in fixed time, ensuring that the upper bound of the system convergence time is not affected by the initial value of the system. Furthermore, the maneuvering movement of the target is considered as a system disturbance, and an extended state observer is employed to estimate and compensate for it in the guidance law. Lastly, by applying consensus theory and distributed communication topology, the remaining flight time of each flight vehicle is syn-chronized to ensure that they intercept the target simulta-neously with different impact angles. Simulation experiments are conducted to validate the effectiveness of the proposed cooper-ative interception and guidance method. 展开更多
关键词 fixed-time control communication topology con-sensus theory impact angle cooperative guidance
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Effect of 3D printing angle on microstructure and mechanical properties of silica ceramic cores by stereolithography
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作者 Yue Gu Wen-yan Duan +3 位作者 Gong Wang Bing-shan Liu Xiao-dong Liu Shan Li 《China Foundry》 2025年第5期534-544,共11页
Ceramic cores fabricated by stereolithography exhibit great potential in casting turbine blades.Previous research on ceramic core molding was primarily conducted using vertical printing techniques,which not only resul... Ceramic cores fabricated by stereolithography exhibit great potential in casting turbine blades.Previous research on ceramic core molding was primarily conducted using vertical printing techniques,which not only resulted in lengthy molding durations but also compromised the mechanical strength.In this work,silica(SiO--_2)ceramic cores,with fine complex geometric shapes,were fabricated using 65vol.%ceramic slurry by digital light processing(DLP)with different printing angles.Printing angles significantly impact the surface accuracy,shrinkage,printing efficiency of green bodies,as well as the microstructure and mechanical properties of sintered ceramic core samples.As the printing angle in the green body increases,the bonding area decreases,surface roughness on the XY plane worsens,shrinkage in the Z direction becomes more pronounced,and the printing efficiency declines.Similarly,an increase in the printing angle in the sintered body leads to a reduction in bending strength.At a printing angle of 30°,the printing time is reduced to half of that at 90°,which improves the molding efficiency.Meanwhile,the obtained bulk density of 1.71 g·cm~(-3),open porosity of 24%,and fiexural strength of 10.6±1 MPa can meet the requirements of sintered ceramic cores.Therefore,designing and optimizing the printing angles can achieve the balance between shrinkage,printing efficiency,and fiexural strength. 展开更多
关键词 SILICA ceramic core digital light processing printing angle mechanical properties
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Phase angle as a prognostic biomarker in metastatic colorectal cancer: A prospective trial
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作者 Domina Kekez Juraj Prejac +6 位作者 Gordan Adzic Niksa Librenjak Irma Gorsic Danijela Jonjic Zeljko Krznaric Goran Augustin Stjepko Plestina 《World Journal of Gastrointestinal Oncology》 2025年第4期264-273,共10页
BACKGROUND Colorectal cancer(CRC)represents a major global public health issue,ranking as the third most common cancer worldwide.Given the substantial prevalence of CRC,there is a critical need to identify precise pro... BACKGROUND Colorectal cancer(CRC)represents a major global public health issue,ranking as the third most common cancer worldwide.Given the substantial prevalence of CRC,there is a critical need to identify precise prognostic and predictive biomar-ker tools for better treatment outcomes.Phase angle(PA)has been proposed as a prognostic marker in various non-malignant and malignant clinical conditions.AIM To investigate the relationship between PA and survival outcomes in the first-line treatment of metastatic CRC(mCRC).METHODS In this prospective observational study,we obtained data on patients who started first-line systemic chemotherapy from the beginning of 2020 until the end of 2022.The PA,assessed by the bioelectrical impedance analysis scale,was evaluated as a possible prognostic factor for treatment outcomes,which were measured as pro-gression-free survival(PFS)and objective response rate(ORR).RESULTS Using the cut-point value for PA set at 4.60°,144 patients were divided into two cohorts.The high PA group of patients exhibited a significantly longer median PFS than the low PA group,14.8 vs 10.5 months,respectively.No difference in ORR was observed.However,patients with PA≥4.60°had a higher disease control rate.CONCLUSION PA represents a novel and objective pre-chemotherapy prognostic factor to identify mCRC patients who are at increased risk of a worse survival outcome. 展开更多
关键词 Phase angle Bioimpedance scale Metastatic colorectal cancer Treatment outcomes First-line chemotherapy
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Stability assessment of inverter-dominated power systems considering coupling between phase angle and voltage dynamics
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作者 Cong Fu Shuiping Zhang +1 位作者 Shun Li Feng Liu 《iEnergy》 2025年第3期157-164,共8页
The integration of renewable energy sources(RESs)with inverter interfaces has fundamentally reshaped power system dynamics,challenging traditional stability analysis frameworks designed for synchronous generator-domin... The integration of renewable energy sources(RESs)with inverter interfaces has fundamentally reshaped power system dynamics,challenging traditional stability analysis frameworks designed for synchronous generator-dominated grids.Conventional classifica-tions,which decouple voltage,frequency,and rotor angle stability,fail to address the emerging strong voltage‒angle coupling effects caused by RES dynamics.This coupling introduces complex oscillation modes and undermines system robustness,neces-sitating novel stability assessment tools.Recent studies focus on eigenvalue distributions and damping redistribution but lack quantitative criteria and interpretative clarity for coupled stability.This work proposes a transient energy-based framework to resolve these gaps.By decomposing transient energy into subsystem-dissipated components and coupling-induced energy exchange,the method establishes stability criteria compatible with a broad variety of inverter-interfaced devices while offering an intuitive energy-based interpretation for engineers.The coupling strength is also quantified by defining the relative coupling strength index,which is directly related to the transient energy interpretation of the coupled stability.Angle‒voltage coupling may induce instability by injecting transient energy into the system,even if the individual phase angle and voltage dynamics themselves are stable.The main contributions include a systematic stability evaluation framework and an energy decomposition approach that bridges theoretical analysis with practical applicability,addressing the urgent need for tools for managing modern power system evolving stability challenges. 展开更多
关键词 Power system stability dynamic coupling inverter-interfaced device stability criteria phase angle dynamics voltage dynamics
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LeafPoseNet:A low-cost,high-accuracy method for estimating flag leaf angle in wheat
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作者 Qi Wang Fujun Sun +4 位作者 Yi Qiao Zongyang Li Shusong Zheng Hong-Qing Ling Ni Jiang 《The Crop Journal》 2025年第5期1543-1553,共11页
Flag leaf angle(FLANG)is one of the key traits in wheat breeding due to its impact on plant architecture,light interception,and yield potential.An image-based method of measuring FLANG in wheat would reduce the labor ... Flag leaf angle(FLANG)is one of the key traits in wheat breeding due to its impact on plant architecture,light interception,and yield potential.An image-based method of measuring FLANG in wheat would reduce the labor and error of manual measurement of this trait.We describe a method for acquiring in-field FLANG images and a lightweight deep learning model named LeafPoseNet that incorporates a spatial attention mechanism for FLANG estimation.In a test dataset with wheat varieties exhibiting diverse FLANG,LeafPoseNet achieved high accuracy in predicting the FLANG,with a mean absolute error(MAE)of 1.75°,a root mean square error(RMSE)of 2.17°,and a coefficient of determination(R2)of 0.998,significantly outperforming established models such as YOLO12x-pose,YOLO11x-pose,HigherHRNet,Lightweight-OpenPose,and LitePose.We performed phenotyping and genome-wide association study to identify the genomic regions associated with FLANG in a panel of 221 diverse bread wheat genotypes,and identified 10 quantitative trait loci.Among them,qFLANG2B.2 was found to harbor a potential causal gene,TraesCS2B01G313700,which may regulate FLANG formation by modulating brassinosteroid levels.This method provides a low-cost,high-accuracy solution for in-field phenotyping of wheat FLANG,facilitating both wheat FLANG genetic studies and ideal plant type breeding. 展开更多
关键词 WHEAT Flag leaf angle Lightweight network LeafPoseNet Genome-wide association study
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Effect of Rake Angle on DTMB Marine Propeller
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作者 Muhammad Suleman Sadiq Adil Loya +1 位作者 Imran Mushtaque Wasim Akram 《Sustainable Marine Structures》 2025年第1期21-34,共14页
The marine propeller typically functions within thefilowfiield generated by a water vehicle.Investigations into the geometric parameters of the propeller are commonly conducted under open‑water conditions as simultane... The marine propeller typically functions within thefilowfiield generated by a water vehicle.Investigations into the geometric parameters of the propeller are commonly conducted under open‑water conditions as simultaneously simulating both vehicle and propeller holds several computational challenges.While during operation,this propellant device must face several forces like gravity,hydrodynamic load,and centrifugal force,which cause different problems like cavitation and structural failure,etc.Since these issues affect performance,it necessitates comprehensive analysis.In this study,hydrodynamic analysis is performed by using commercial software STAR CCM+.In hydrodynamic analysis,the effect of the rake angles–5°,5°,10°and 15°on hydrodynamic coeffiicients and effiiciency of the DTMB 4119 in the open water is analyzed using Computational Fluid Dynamics(CFD)and the control volume approach.The Shear Stress Transport(SST)k‑ωturbulence model is used in Computational Fluid Dynamics(CFD)simulation.Hydrodynamic analysis reveals that the rake angles 5°and 10°cause the open water effiiciency of David Taylor Model Basin(DTMB)4119 to improve by 0.4 to 1.32%with exception of the rake angles–5°and 15°,which possess different effects on effiiciency.The angle–5°causes a decrease in propeller effiiciency under heavy loading situations(low advance coeffiicient)apart from a minorfiluctuation at light loading conditions(high advance coeffiicient),while the angle 15°produces a drop in effiiciency by higher advance ratios but little variation at lower advance ratios. 展开更多
关键词 DTMB 4119 Marine Propeller Rake angle Open Water Performance Unsteady Solution Hydrodynamic Analysis
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Aqueous humor adipokine profile of primary open angle glaucoma patients and cataract patients with or without metabolic disorders
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作者 Zi-Yao Xia Ke Xu +6 位作者 Wei-Jia Zhang De-Fu Wu Zhe Pan Hao-Cheng Xian Xue-Min Li Huai-Zhou Wang Chun Zhang 《International Journal of Ophthalmology(English edition)》 2025年第4期615-626,共12页
AIM:To investigate the role of adipokines in primary open angle glaucoma(POAG)by comparing the levels of these molecules in the aqueous humor among POAG patients and cataract patients with or without metabolic disorde... AIM:To investigate the role of adipokines in primary open angle glaucoma(POAG)by comparing the levels of these molecules in the aqueous humor among POAG patients and cataract patients with or without metabolic disorders.METHODS:In this cross-sectional study,aqueous humor samples of 22 eyes of POAG patients(POAG group),24 eyes of cataract patients without metabolic disorders(cataract group),and 24 eyes of cataract patients with metabolic disorders(cataract+metabolic disorders group)were assessed for 15 adipokines by Luminex bead-based multiplex array.The correlation between aqueous humor adipokines and clinical indicators of POAG was analyzed and compared across the groups.RESULTS:The analysis revealed that the levels of adiponectin,leptin,adipsin,retinol-binding protein 4(RBP4),angiopoietin-2,angiopoietin-like protein 4(ANGPTL4),chemokine(C-C motif)ligand 2(CCL2),interleukin-8(IL-8),and interleukin-18(IL-18)in the aqueous humor of the POAG group were significantly higher than those in the cataract group.Additionally,the level of angiopoietin-2 in the POAG group was higher than in the cataract+metabolic disorders group.However,no significant correlation was found between the levels of adipokines in the POAG group and intraocular pressure(IOP),severity of POAG,or the use of glaucoma medications.CONCLUSION:This study demonstrates significant differences in aqueous humor adipokine levels between POAG and cataract patients.The findings suggest that the levels of aqueous humor adipokines may reflect the inflammatory states in POAG and systemic metabolic abnormalities. 展开更多
关键词 glaucoma biomarkers ADIPOKINE primary open angle glaucoma aqueous humor metabolic disorder
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