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ZmbZIP27 regulates nitrogen-mediated leaf angle by modulating lignin deposition in maize 被引量:1
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作者 Huan Chen Xiaoping Gong +3 位作者 Yu Guo Jingjuan Yu Wen-Xue Li Qingguo Du 《The Crop Journal》 SCIE CSCD 2024年第5期1404-1413,共10页
In grain crops such as maize(Zea mays),leaf angle(LA)is a key agronomic trait affecting light interception and thus planting density and yield.Nitrogen(N)affects LA in plants,but we lack a good understanding of how N ... In grain crops such as maize(Zea mays),leaf angle(LA)is a key agronomic trait affecting light interception and thus planting density and yield.Nitrogen(N)affects LA in plants,but we lack a good understanding of how N regulates LA.Here,we report that N deficiency enhanced lignin deposition in the ligular region of maize seedlings.In situ hybridization showed that the bZIP transcription factor gene ZmbZIP27 is mainly expressed in the phloem of maize vascular bundles.Under N-sufficient conditions,transgenic maize overexpressing ZmbZIP27 showed significantly smaller LA compared with wild type(WT).By contrast,zmbzip27_(ems)mutant showed larger LA under both N-deficient and N-sufficient conditions compared with WT.Overexpression of ZmbZIP27 enhanced lignin deposition in the ligular region of maize in the field.We further demonstrated that ZmbZIP27 could directly bind the promoters of the microRNA genes ZmMIR528a and ZmMIR528b and negatively regulate the expression levels of ZmmiR528.ZmmiR528 knockdown transgenic maize displayed erect architecture in the field by increasing lignin content in the ligular region of maize.Taken together,these results indicate that ZmbZIP27 regulates N-mediated LA size by regulating the expression of ZmmiR528 and modulating lignin deposition in maize. 展开更多
关键词 MAIZE NITROGEN Leaf angle Ligular region Lignin deposition
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An improved algorithm based on equivalent sound velocity profile method at large incident angle
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作者 Qianqian Li Qian Tong +3 位作者 Fanlin Yang Qi Li Zhihao Juan Yu Luo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期161-167,共7页
With the development of ultra-wide coverage technology,multibeam echo-sounder(MBES)system has put forward higher requirements for localization accuracy and computational efficiency of ray tracing method.The classical ... With the development of ultra-wide coverage technology,multibeam echo-sounder(MBES)system has put forward higher requirements for localization accuracy and computational efficiency of ray tracing method.The classical equivalent sound speed profile(ESSP)method replaces the measured sound velocity profile(SVP)with a simple constant gradient SVP,reducing the computational workload of beam positioning.However,in deep-sea environment,the depth measurement error of this method rapidly increases from the central beam to the edge beam.By analyzing the positioning error of the ESSP method at edge beam,it is discovered that the positioning error increases monotonically with the incident angle,and the relationship between them could be expressed by polynomial function.Therefore,an error correction algorithm based on polynomial fitting is obtained.The simulation experiment conducted on an inclined seafloor shows that the proposed algorithm exhibits comparable efficiency to the original ESSP method,while significantly improving bathymetry accuracy by nearly eight times in the edge beam. 展开更多
关键词 equivalent sound speed profile ray tracing method large incident angle edge beam deep sea error correction multibeam echo-sounder system
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Influence of Omega 3 Fatty Acid Supplementation on Phase Angle Values of People Living with HIV/AIDS with Lipodystrophy Secondary to Antiretroviral Therapy: A Randomized Clinical Trial
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作者 Thalita Bandeira Dantas Alline Peralta Castro +1 位作者 Fernando de Souza Flexa Ribeiro Filho Rosana Maria Feio Libonati 《Food and Nutrition Sciences》 CAS 2024年第1期58-70,共13页
Objective: The measurement of phase angles is an important monitoring parameter and supplementation with omega-3 could promote benefits by modulating the electrical potential of membranes and increasing body cell mass... Objective: The measurement of phase angles is an important monitoring parameter and supplementation with omega-3 could promote benefits by modulating the electrical potential of membranes and increasing body cell mass. This study aimed to evaluate the effectiveness of omega-3 fatty acid supplementation on the phase angle of people living with HIV/AIDS. Methods: In this study, 63 individuals of all genders who were undergoing outpatient follow-up and showed lipodystrophy due to highly active antiretroviral therapy were analyzed. Our sample consisted of two groups, one that received supplementation containing 2550 mg of omega-3/day (1080 mg of eicosapentaenoic acid and 720 mg of docosahexaenoic acid) for three months (n = 32) and another that underwent nutrition guidance (n = 31). Phase angle and body cell mass were assessed for both groups and compared at the beginning of research (T0) and after our intervention (T1) for each group separately. Results: Phase angle averaged 6.45° ± 1.06 SD. The comparison between T0 and T1 showed a significant increase in phase angle and body cell mass, whereas the guidance group showed a decrease in body cell mass at T1 in relation to T0, with a significant p-value. Variance in phase angle between moments showed significant values between T0 and T1 in the supplementation group for all genders. Conclusion: Omega-3 positively modulated patients phase angle and body cell mass, but we emphasize the need for other studies that can solidify knowledge about supplementation dosage and intervention time. 展开更多
关键词 HIV LIPODYSTROPHY Omega-3 Phase angle
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Identification of the BTA8 gene reveals the contribution of natural variation to tiller angle in rice
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作者 Junrong Liu Xingyu Wang +7 位作者 Jing Wang Junhua Ye Mengchen Zhang Qun Xu Yaolong Yang Xinghua Wei Baoyan Jia Yue Feng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2868-2871,共4页
Plant architecture is a collection of major agronomic traits that determines rice grain production,and it is mainly influenced by tillering,tiller angle,plant height and panicle morphology(Wang and Li 2006).Tiller ang... Plant architecture is a collection of major agronomic traits that determines rice grain production,and it is mainly influenced by tillering,tiller angle,plant height and panicle morphology(Wang and Li 2006).Tiller angle is one of the critical components that determines rice plant architecture,which in turn influences grain yield mainly due to its large impact on plant density(Wang et al.2022). 展开更多
关键词 angle PANICLE AGRONOMIC
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Visualizing the Local Twist Angle Variation within and between Domains of Twisted Bilayer Graphene
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作者 户佳玮 朱诗雨 +7 位作者 胡倩颖 王云昊 申承民 杨海涛 竺晓山 郇庆 许杨 高鸿钧 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期146-151,共6页
Moirésuperlattices in twisted two-dimensional materials have emerged as ideal platforms for engineering quantum phenomena,which are highly sensitive to twist angles,including both the global value and the spatial... Moirésuperlattices in twisted two-dimensional materials have emerged as ideal platforms for engineering quantum phenomena,which are highly sensitive to twist angles,including both the global value and the spatial inhomogeneity.However,only a few methods provide spatial-resolved information for characterizing local twist angle distribution. 展开更多
关键词 angle TWIST TWIST
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Experimental Study of Local Scour Around Four Piles Under Different Attack Angles and Gap Ratios
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作者 LIU Ming-ming TANG Guo-qiang +1 位作者 JIN Xin GENG Shao-yang 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期612-624,共13页
In an effort to investigate and quantify the patterns of local scour,researchers embarked on an in-depth study using a systematic experimental approach.The research focused on the effects of local scour around a set o... In an effort to investigate and quantify the patterns of local scour,researchers embarked on an in-depth study using a systematic experimental approach.The research focused on the effects of local scour around a set of four piles,each subjected to different hydromechanical conditions.In particular,this study aimed to determine how different attack angles—the angles at which the water flow impinges on the piles,and gap ratios—the ratios of the spacing between the piles to their diameters,influence the extent and nature of scour.A comprehensive series of 35 carefully designed experiments were orchestrated,each designed to dissect the nuances in how the gap ratio and attack angle might contribute to changes in the local scour observed at the base of pile groups.During these experimental trials,a wealth of local scour data were collected to support the analysis.These data included precise topographic profiles of the sediment bed around the pile groups,as well as detailed scour time histories showing the evolution of scour at strategic feature points throughout the test procedure.The analysis of the experimental data provided interesting insights.The study revealed that the interplay between the gap ratio and the attack angle had a pronounced influence on the scouring dynamics of the pile groups.One of the key observations was that the initial phases of scour,particularly within the first hour of water flow exposure,were characterized by a sharp increase in the scour depth occurring immediately in front of the piles.After this initial rapid development,the scour depth transitioned to a more gradual change rate.In contrast,the scour topography around the piles continuously evolved.This suggests that sediment displacement and the associated sculpting of the seabed around pile foundations are sustained and progressive processes,altering the underwater landscape over time.The results of this empirical investigation have significant implications for the design and construction of offshore multi-pile foundations,providing a critical reference for engineers and designers to estimate the expected scour depth around such structures,which is an integral part of decisions regarding foundation design,selection of structural materials,and implementation of scour protection measures. 展开更多
关键词 local scour PILES gap ratio attack angle
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In situ calibrated angle between the quantization axis and the propagating direction of the light field for trapping neutral atoms
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作者 郭瑞军 何晓东 +7 位作者 盛诚 王坤鹏 许鹏 刘敏 王谨 孙晓红 曾勇 詹明生 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期318-323,共6页
The recently developed magic-intensity trapping technique of neutral atoms efficiently mitigates the detrimental effect of light shifts on atomic qubits and substantially enhances the coherence time. This technique re... The recently developed magic-intensity trapping technique of neutral atoms efficiently mitigates the detrimental effect of light shifts on atomic qubits and substantially enhances the coherence time. This technique relies on applying a bias magnetic field precisely parallel to the wave vector of a circularly polarized trapping laser field. However, due to the presence of the vector light shift experienced by the trapped atoms, it is challenging to precisely define a parallel magnetic field, especially at a low bias magnetic field strength, for the magic-intensity trapping of85Rb qubits. In this work, we present a method to calibrate the angle between the bias magnetic field and the trapping laser field with the compensating magnetic fields in the other two directions orthogonal to the bias magnetic field direction. Experimentally, with a constantdepth trap and a fixed bias magnetic field, we measure the respective resonant frequencies of the atomic qubits in a linearly polarized trap and a circularly polarized one via the conventional microwave Rabi spectra with different compensating magnetic fields and obtain the corresponding total magnetic fields via the respective resonant frequencies using the Breit–Rabi formula. With known total magnetic fields, the angle is a function of the other two compensating magnetic fields.Finally, the projection value of the angle on either of the directions orthogonal to the bias magnetic field direction can be reduced to 0(4)° by applying specific compensating magnetic fields. The measurement error is mainly attributed to the fluctuation of atomic temperature. Moreover, it also demonstrates that, even for a small angle, the effect is strong enough to cause large decoherence of Rabi oscillation in a magic-intensity trap. Although the compensation method demonstrated here is explored for the magic-intensity trapping technique, it can be applied to a variety of similar precision measurements with trapped neutral atoms. 展开更多
关键词 quantization axis trapping laser angle compensating magnetic fields
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Suppression of Vortex-Induced Vibration Caused by A Terebridae-Inspired Cylinder with Different Helical Angles
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作者 YU Qi-dong MAO Zhao-yong +1 位作者 TIAN Wen-long WANG Wei 《China Ocean Engineering》 SCIE EI CSCD 2024年第5期739-754,共16页
Biomimetic design has recently received widespread attention.Inspired by the Terebridae structure,this paper provides a structural form for suppressing vortex-induced vibration(VIV)response.Four different structural f... Biomimetic design has recently received widespread attention.Inspired by the Terebridae structure,this paper provides a structural form for suppressing vortex-induced vibration(VIV)response.Four different structural forms are shown,including the traditional smooth cylinder(P0),and the Terebridae-inspired cylinder with the helical angle of 30°(P_(30)),60°(P_(60)),and 90°(P_(90)).Computational fluid dynamics(CFD)method is adopted to solve the flow pass the Terebridae-inspired structures,and the vibration equation is solved using the Newmark-βmethod.The results show that for P_(30),P_(60) and P_(90),the VIV responses are effectively suppressed in the lock-in region,and P_(60) showed the best VIV suppression performance.The transverse amplitude and the downstream amplitude can be reduced by 82.67%and 91.43%respectively for P_(60) compared with that for P0,and the peak of the mean-drag coefficient is suppressed by 53.33%.The Q-criterion vortices of P_(30),P_(60),and P_(90) are destroyed,with irregular vortices shedding.It is also found that the boundary layer separation is located on the Terebridae-inspired ribs.The twisted ribs cause the separation point to constantly change along the spanwise direction,resulting in the development of the boundary layer separation being completely destroyed.The strength of the wake flow is significantly weakened for the Terebridae-inspired cylinder. 展开更多
关键词 vortex-induced vibration(VIV) Terebridae CYLINDER SUPPRESSION helical angle
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Closed-form guidance law for velocity maximization with impact angle constraint
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作者 ZHANG Jiahui WEN Qiuqiu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1295-1303,共9页
Final velocity and impact angle are critical to missile guidance.Computationally efficient guidance law with compre-hensive consideration of the two performance merits is challeng-ing yet remains less addressed.Theref... Final velocity and impact angle are critical to missile guidance.Computationally efficient guidance law with compre-hensive consideration of the two performance merits is challeng-ing yet remains less addressed.Therefore,this paper seeks to solve a type of optimal control problem that maximizes final velocity subject to equality point constraint of impact angle con-straint.It is proved that the crude problem of maximizing final velocity is equivalent to minimizing a quadratic-form cost of cur-vature.The closed-form guidance law is henceforth derived using optimal control theory.The derived analytical guidance law coincides with the widely-used optimal guidance law with impact angle constraint(OGL-IAC)with a set of navigation parameters of two and six.On this basis,the optimal emission angle is determined to further increase the final velocity.The derived optimal value depends solely on the initial line-of-sight angle and impact angle constraint,and thus practical for real-world appli-cations.The proposed guidance law is validated by numerical simulation.The results show that the OGL-IAC is superior to the benchmark guidance laws both in terms of final velocity and missing distance. 展开更多
关键词 MISSILE guidance law proportional-navigation guidance impact angle
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Suicide risk in juvenile open angle glaucoma patients
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作者 Hye-Jeong Seong Sukyoung Jung Sooyeon Choe 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第10期1880-1886,共7页
AIM:To investigate the association between juvenile open angle glaucoma(JOAG)and mental health among Koreans.METHODS:This study used nationally representative data from the 8th Korea National Health and Nutrition Exam... AIM:To investigate the association between juvenile open angle glaucoma(JOAG)and mental health among Koreans.METHODS:This study used nationally representative data from the 8th Korea National Health and Nutrition Examination Survey(KNHANES)2021.Glaucoma diagnosis followed the International Society of Geographical and Epidemiological Ophthalmology criteria based on glaucomatous structural defects,visual field defects,corrected vision,and intraocular pressure.As outcomes,suicidal behaviors,psychiatric counseling,and depression were evaluated through mental health questionnaires.Odds ratios(ORs)with 95%confidence intervals(CIs)were estimated using logistic regression models,adjusting for covariates.RESULTS:Among 7090 participants,3446 met the inclusion criteria for analysis,and 88(2.6%)were diagnosed with open angle glaucoma(OAG).After adjusting for age,sex,and best-corrected visual acuity(VA),participants with OAG were revealed to have significantly higher odds of suicidal behaviors(i.e.,ideation,planning,or attempts)compared with those without OAG(OR:2.70;95%CI:1.12-6.54;P=0.028).This association remained significant after further adjustments for socioeconomic status,lifestyle factors,and presence of chronic conditions(P=0.031 and 0.035,respectively).However,there was no significant difference for the other two outcomes,psychiatric counseling and depression.An age-stratified analysis revealed a stronger association between OAG and suicidal behaviors in younger JOAG participants(<40y)than in older OAG participants(≥40y;OR:3.80 vs 2.22;95%CI:0.79-18.22 vs 0.56-8.80,respectively).CONCLUSION:OAG patients show a higher risk of suicidal behaviors than those without glaucoma particularly in JOAG patients. 展开更多
关键词 GLAUCOMA juvenile open angle glaucoma SUICIDE suicidal behavior
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Effect of attack angle on the electromagnetic wave transmission characteristics in the hypersonic plasma sheath of a re-entry vehicle
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作者 Xin AI Qiuyue NIE +4 位作者 Zhonglin ZHANG Peiqi CHEN Shulei ZHENG Changshi YAN Guoqiang WEI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第12期49-62,共14页
The attack angle may greatly affect the hypersonic plasma sheaths around the re-entry vehicle,thereby affecting the transmission characteristics of electromagnetic(EM)waves in the sheaths.In this paper,we propose an i... The attack angle may greatly affect the hypersonic plasma sheaths around the re-entry vehicle,thereby affecting the transmission characteristics of electromagnetic(EM)waves in the sheaths.In this paper,we propose an integrated three-dimensional(3D)model with various attack angles and realistic flying conditions of radio attenuation measurement C-II(RAM C-II)re-entry tasks for analyzing the effect of the attack angle on the transmission characteristics of EM waves in the sheaths.It is shown that the electron density and collision frequency of the sheath on the windward side can be increased by an order of magnitude with the increase of the attack angle.Meanwhile,the thickness of the sheath on the leeward side is increased where the electron density and collision frequency are reduced.The EM waves are mainly reflected on the windward plasma sheath due to the cutoff effect,and the radio-frequency(RF)blackout is mitigated if the antenna is positioned on the leeward side.Thus,by planning the trajectory properly and installing the antenna accordingly during the re-entry,it is possible to provide an approach for mitigation of the RF blackout problem to an extent. 展开更多
关键词 attack angle hypersonic plasma sheath re-entry vehicle transmission characteristics
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Acute primary angle closure during the Omicron outbreak
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作者 Dong Fang Wang-Ting Li +9 位作者 Jia Liang Lu Chen Ning-Xin Dou Hui-Yan Zheng Can-Feng Huang Ting Xie Yi-Jing Zhuang Peng-Feng Li Xing-Xing Mao Shao-Chong Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第7期1337-1343,共7页
AIM:To investigate Omicron’s impact on clinical presentation of acute primary angle closure(APAC)in China.METHODS:A consecutive case series with historical controls was conducted at Shenzhen Eye Hospital,the largest ... AIM:To investigate Omicron’s impact on clinical presentation of acute primary angle closure(APAC)in China.METHODS:A consecutive case series with historical controls was conducted at Shenzhen Eye Hospital,the largest specialized hospital in Shenzhen,China.Medical records from a two-month period during the Omicron pandemic(December 1,2022,to January 31,2023)were compared with records from two control groups(12/2018–1/2019 and 12/2021–1/2022)before pandemic.Patients with APAC were included,and the prevalence of APAC and demographic characteristics in Omicron-infected and noninfected patients were compared.RESULTS:Seventy-one(23.43%)out of 303 patients were diagnosed with APAC in the pandemic cohort,which was 2.98 and 2.61 times higher than that in control cohorts(7.87%in 2019,8.96%in 2022,P<0.001).The pandemic cohort has significantly higher Omicron-infected rate(78.87%vs 0 vs 0;P<0.001),lower proportion of glaucoma history(16.90%vs 42.86%vs 41.67%,P=0.005),higher surgical rate(95.77%vs 83.33%vs 78.57%,P=0.024),higher total medical costs and larger pupil diameter(5.63±0.15 vs 4.68±0.15 vs 4.69±0.22 mm,P<0.01).In 83%Omicron-infected patients,ocular symptoms appeared within 3d after systemic symptoms onset.In multivariate analysis,Omicron infection(P<0.001)was the only independent predictor of pupil diameter.CONCLUSION:In the Omicron epidemic in China,there is an increase of prevalence and severity of APAC,particularly focusing on the first 3d following infection. 展开更多
关键词 Omicron acute primary angle closure ocular symptoms
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Fine mapping of two recessive genes TaFLA1 and TaSPL8 controlling flag leaf angle in bread wheat
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作者 Qiushi Wang Jiaxing Bai +11 位作者 Hongchun Xiong Yongdun Xie Chaojie Wang Jiayu Gu Linshu Zhao Huiyuan Li Jinfeng Zhang Shirong Zhao Yuping Ding Zhengwu Fang Huijun Guo Luxiang Liu 《The Crop Journal》 SCIE CSCD 2024年第4期1159-1167,共9页
Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,j... Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,je0407,with an 84.34%-89.35%smaller flag leaf angle compared with the wild type.The mutant also had an abnormal lamina joint and no ligule or auricle.Genetic analysis indicated that the ligule was controlled by two recessive genes,which were mapped to chromosomes 2AS and 2DL.The mutant allele on chromosome 2AS was named Tafla1b,and it was fine mapped to a 1 Mb physical interval.The mutant allele on chr.2DL was identified as Taspl8b,a novel allele of TaSPL8 with a missense mutation in the second exon,which was used to develop a cleaved amplified polymorphic sequence marker.F3 and F4 lines derived from crosses between Jing411 and je0407 were genotyped to investigate interactions between the Tafla1b and Taspl8b alleles.Plants with the Tafla1b/Taspl8a genotype had 58.41%-82.76%smaller flag leaf angles,6.4%-24.9%shorter spikes,and a greater spikelet density(0.382 more spikelets per cm)compared with the wild type.Plants with the Tafla1a/Taspl8b genotype had 52.62%-82.24%smaller flag leaf angles and no differences in plant height or spikelet density compared with the wild type.Tafla1b/Taspl8b plants produced erect leaves with an abnormal lamina joint.The two alleles had dosage effects on ligule formation and flag leaf angle,but no significant effect on thousand-grain weight.The mutant alleles provide novel resources for improvement of wheat plant architecture. 展开更多
关键词 WHEAT Ligule Flag leaf angle Fine mapping Tafla1 Taspl8
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Experimental Study on the Variation of Optical Imaging Characteristics with Zenith Angle due to Internal Solitary Waves in Sunglint
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作者 LIU Tengfei SUN Lina +4 位作者 CHANG Zhe ZHANG Meng LIANG Keda MENG Junmin WANG Jing 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期943-952,共10页
Internal solitary waves(ISWs)change the roughness of the sea surface,thus producing dark and bright bands in optical images.However,reasons for changes in imaging characteristics with the solar zenith angle remain unc... Internal solitary waves(ISWs)change the roughness of the sea surface,thus producing dark and bright bands in optical images.However,reasons for changes in imaging characteristics with the solar zenith angle remain unclear.In this paper,the optical imaging pattern of ISWs in sunglint under different zenith angles of the light source is investigated by collecting optical images of ISWs through physical simulation.The experiment involves setting 10 zenith angles of the light source,which are divided into area a the optical images of ISWs in the three areas show dark-bright mode,single bright band,and bright-dark mode,which are consistent with those observed by optical remote sensing.In addition,this study analyzed the percentage of the dark and bright areas of the bands and the change in the relative gray difference and found changes in both areas under different zenith angles of the light source.The MODIS and ASAR images display a similar brightness-darkness distance of the same ISWs.Therefore,the relationship between the brightness-darkness distance and the characteristic half-width of ISWs is determined in accordance with the eKdV theory and the imaging mechanism of ISWs of the SAR image.Overall,the relationship between them in the experiment is almost consistent with the theoretical result. 展开更多
关键词 internal solitary waves optical imaging characteristic laboratory simulation zenith angle sunglint
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An approach for determination of lateral limit angle in kinematic planar sliding analysis for rock slopes
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作者 Xiaojuan Yang Jie Hu +1 位作者 Honglei Sun Jun Zheng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1305-1314,共10页
Planar sliding is one of the frequently observed types of failure in rock slopes.Kinematic analysis is a classic and widely used method to examine the potential failure modes in rock masses.The accuracy of planar slid... Planar sliding is one of the frequently observed types of failure in rock slopes.Kinematic analysis is a classic and widely used method to examine the potential failure modes in rock masses.The accuracy of planar sliding kinematic analysis is significantly influenced by the value assigned to the lateral limit angleγlim.However,the assignment ofγlim is currently used generally based on an empirical criterion.This study aims to propose an approach for determining the value ofγlim in deterministic and probabilistic kinematic planar sliding analysis.A new perspective is presented to reveal thatγlim essentially influences the probability of forming a potential planar sliding block.The procedure to calculate this probability is introduced using the block theory method.It is found that the probability is correlated with the number of discontinuity sets presented in rock masses.Thus,different values ofγlim for rock masses with different sets of discontinuities are recommended in both probabilistic and deterministic planar sliding kinematic analyses;whereas a fixed value ofγlim is commonly assigned to different types of rock masses in traditional method.Finally,an engineering case was used to compare the proposed and traditional kinematic analysis methods.The error rates of the traditional method vary from 45%to 119%,while that of the proposed method ranges between 1%and 17%.Therefore,it is likely that the proposed method is superior to the traditional one. 展开更多
关键词 Kinematic analysis Block theory Planar sliding Lateral limit angle Rock slope
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Effect of Sweptback Angle of a Delta Wing on Surface Pressure Distribution at Supersonic Mach Numbers
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作者 Shamitha Shetty Asha Crasta +2 位作者 Sher Afghan Khan Abdul Aabid Muneer Baig 《Fluid Dynamics & Materials Processing》 EI 2024年第10期2353-2376,共24页
The purpose of this work is to shed light on the effect of the pivot position on the surface pressure distribution over a 3D wing in different flight conditions.The study is intended to support the design and developm... The purpose of this work is to shed light on the effect of the pivot position on the surface pressure distribution over a 3D wing in different flight conditions.The study is intended to support the design and development of aerospace vehicles where stability analysis,performance optimization,and aircraft design are of primary importance.The following parameters are considered:Mach numbers(M)of 1.3,1.8,2.3,2.8,3.3,and 3.8,angle of incidence(θ)in the range from 5°to 25°,pivot position from h=0.2 to 1.The results of the CFD numerical simulations match available analytical data,thereby providing evidence for the reliability of the used approach.The findings provide valuable insights into the relationship between the surface pressure distribution,the Mach number and the angle of incidence. 展开更多
关键词 Mach number angles of incidence stability analysis performance optimization
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Analysis of SMOC2 gene variants in familial and nonfamilial primary open angle glaucoma Pakistani patients
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作者 Ashok Kumar Narsani Feriha Fatima Khidri +7 位作者 Muhammad Rafiq Jalpa Bai Hina Shaikh Yar Muhammad Waryah Syed Habib Ahmed Naqvi Preety Kumari Mahesh Kumar Lohano Ali Muhammad Waryah 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第12期2185-2191,共7页
AIM:To find out the association of secreted protein acidic and rich in cysteine(SPARC)-related modular calcium binding 2(SMOC2)gene variants rs2255680 and rs13208776 with genotypic and phenotypic characteristics in bo... AIM:To find out the association of secreted protein acidic and rich in cysteine(SPARC)-related modular calcium binding 2(SMOC2)gene variants rs2255680 and rs13208776 with genotypic and phenotypic characteristics in both familial and non-familial primary open angle glaucoma(POAG)patients.METHODS:A total of 212 POAG patients,comprising 124 familial and 88 non-familial,were enrolled.For genotyping the SMOC2 variant rs2255680,amplification refractory mutation system(ARMS)-polymerase chain reaction(PCR)method and PCR-restriction fragment length polymorphism(PCR-RFLP)were utilized for analyzing rs13208776 variant.RESULTS:The mean age of familial POAG patients was 50.92±9.12y,with 78 males and 46 females.The mean age of non-familial POAG patients was 53.14±13.44y,with 52 males and 36 females.The SMOC2 gene variant rs13208776 showed the significant association with POAG between familial and non-familial groups.The homozygous G/G variant was frequent among non-familial(60.2%)whereas the heterozygous G/A variant was more frequent in familial POAG patients(46%).There were significant differences in G/A variant between familial and non-familial glaucoma patients,and the risk was decreased to 0.53-fold in non-familial glaucoma patients[odds ratio(OR):0.53;95%confidence interval(CI):0.29-0.94;P=0.033]in codominant model.The risk was further reduced to 0.49-fold(95%CI:0.28-0.86;P=0.012)in dominant model for non-familial patients.No significant association of SMOC2 gene variant rs2255680 between familial and non-familial glaucoma patients was found in our population.The haplotype analysis showed the decreased risk for TA[OR:0.48(95%CI:0.29-0.79);P=0.004]and an increased risk for TG[OR=2.28(95%CI:1.22-4.25);P=0.01]haplotypes.CONCLUSION:Current findings show significant association of SMOC2 gene variant rs13208776 with POAG between familial and non-familial Pakistani patients. 展开更多
关键词 GLAUCOMA primary open angle glaucoma SMOC2 GENE VARIANT FAMILIAL non-familial
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A highly sensitive fluorescent probe RN-NA reveals peroxynitrite as a novel biomarker for primary open angle glaucoma
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作者 Bo Qin Yuan Lei +3 位作者 Luo Bao You-Jia Zhang Ke-Yin Liu Yu-Hong Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期219-227,共9页
AIM:To directly quantify peroxynitrite(ONOO-)using a highly sensitive fluorescence resonance energy transfer probe RN-NA,investigate the association between ONOOand primary open angle glaucoma(POAG),and clarify whethe... AIM:To directly quantify peroxynitrite(ONOO-)using a highly sensitive fluorescence resonance energy transfer probe RN-NA,investigate the association between ONOOand primary open angle glaucoma(POAG),and clarify whether RN-NA could be used as a potential tool for POAG diagnosis.METHODS:Plasma and aqueous humor(AH)samples were collected from POAG patients(n=100,age:59.70±6.87y)and age-related cataract(ARC)patients(n=100,age:61.15±4.60y)admitted to our hospital.Next,RN-NA was used to detect ONOO-in plasma and AH samples,and the relationship between ONOO-level and POAG was analyzed using binary logistic regression.Besides,Pearson correlation analysis was applied to characterize the correlation of the levels of ONOO-with the patients’age,intraocular pressure(IOP),and mean deviation of visual field testing.The ONOO-scavenger MnTMPyP was employed to treat the 3-morpholinosyndnomine(SIN-1)-induced ocular hypertension in mice(n=7,6-8wk).Finally,the IOP and ONOO-in both eyes were measured 30min after the last drug treatment.RESULTS:ONOO-levels of AH and plasma were significantly higher in the POAG group than in the ARC group(P<0.01).Additionally,ONOO-levels were closely correlated with POAG in a binary logistic regression analysis[odds ratio(OR)=1.008,95%confidence interval(CI):1.002-1.013,P<0.01 for AH;OR=1.004,95%CI:1.002-1.006,P<0.001 for plasma].Pearson correlation analysis showed that ONOO-levels in AH or plasma were positively associated with visual field defects(R=0.51,P<0.01 for AH;R=0.45,P<0.001 for plasma),and ONOO-levels in plasma and AH were correlated in the POAG group(R=0.69,P<0.001).However,administering MnTMPyP to mouse eyes reversed the elevated IOP caused by SIN-1(P<0.05).CONCLUSION:ONOO-levels in AH and plasma,detected by RN-NA,are significantly related to POAG and positively correlated with visual field defects in POAG patients.Hence,ONOO-is a potential biomarker of POAG,especially advanced POAG.Besides,anti-nitration compounds may be novel ocular hypotensive agents based on the animal study. 展开更多
关键词 PEROXYNITRITE fluorescent probe RN-NA primary open angle glaucoma 3-morpholinosyndnomine
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Blade Wrap Angle Impact on Centrifugal Pump Performance:Entropy Generation and Fluid-Structure Interaction Analysis
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作者 Hayder Kareem Sakran Mohd Sharizal Abdul Aziz Chu Yee Khor 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期109-137,共29页
The centrifugal pump is a prevalent power equipment widely used in different engineering patterns,and the impeller blade wrap angle significantly impacts its performance.A numerical investigation was conducted to anal... The centrifugal pump is a prevalent power equipment widely used in different engineering patterns,and the impeller blade wrap angle significantly impacts its performance.A numerical investigation was conducted to analyze the influence of the blade wrap angle on flow characteristics and energy distribution of a centrifugal pump evaluated as a low specific speed with a value of 69.This study investigates six impellermodels that possess varying blade wrap angles(95°,105°,115°,125°,135°,and 145°)that were created while maintaining the same volute and other geometrical characteristics.The investigation of energy loss was conducted to evaluate the values of total and entropy generation rates(TEG,EGR).The fluid-structure interaction was considered numerically using the software tools ANSYS Fluent and ANSYSWorkbench.The elastic structural dynamic equation was used to estimate the structural response,while the shear stress transport k–ωturbulence model was utilized for the fluid domain modeling.The findings suggest that the blade wrap angle has a significant influence on the efficiency of the pump.The impeller featuring a blade wrap angle of 145°exhibits higher efficiency,with a notable increase of 3.76%relative to the original model.Variations in the blade wrap angle impact the energy loss,shaft power,and pump head.The model with a 145°angle exhibited a maximum equivalent stress of 14.8MPa and a total deformation of 0.084 mm.The results provide valuable insights into the intricate flow mechanism of the centrifugal pump,particularly when considering various blade wrap angles. 展开更多
关键词 Centrifugal pump blade wrap angle entropy generation theory fluid-structure interaction hydraulic performance
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Effect of Nozzle Inclination Angle on Fuel-Air Mixing and Combustion in a Heavy Fuel Engine
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作者 Zhigang Wang Bin Zheng +4 位作者 Peidong Zhao Baoli Wang Fanyan Meng Wenke Xu Jian Meng 《Fluid Dynamics & Materials Processing》 EI 2024年第2期365-382,共18页
Heavy-fuel engines are widely used in UAVs(Unmanned Autonomous Vehicles)because of their reliability and high-power density.In this study,a combustion model for an in-cylinder direct injection engine has been imple-me... Heavy-fuel engines are widely used in UAVs(Unmanned Autonomous Vehicles)because of their reliability and high-power density.In this study,a combustion model for an in-cylinder direct injection engine has been imple-mented using the AVL FIRE software.The effects of the angle of nozzle inclination on fuel evaporation,mixture distribution,and combustion in the engine cylinder have been systematically studied at 5500 r/min and consider-ing full load cruise conditions.According to the results,as the angle of nozzle inclination increases,the maximum combustion explosion pressure in the cylinderfirst increases and then it decreases.When the angle of nozzle incli-nation is less than 45°,the quality of the mixture in the cylinder and the combustion performance can be improved by increasing the angle.When the angle of nozzle inclination is greater than 45°,however,the mixture unevenness increases slightly with the angle,leading to a deterioration of the combustion performances.When the angle of nozzle inclination is between 35°and 55°,the overall combustion performance of the engine is rela-tively good.When the angle of nozzle inclination is 45°,the combustion chamber’s geometry and the cylinder’s airflow are well matched with the fuel spray,and the mixture quality is the best.Compared with 25°,the peak heat release rate increases by 20%,and the maximum combustion burst pressure increases by 5.5%. 展开更多
关键词 Aviation heavy fuel piston engine nozzle inclination angle COMBUSTION fuel-air mixing
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