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Coupled DEM-FDM analyses of the effects of falling rock’s shape and impact angle on response of granular cushion and rock shed
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作者 Jingyu Xue Chen Cao +2 位作者 Jianhua Yan Yaopeng Ji Jianping Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3353-3364,共12页
Rock shed is an effective protection measure against rockfall.To investigate the influences of falling rock’s shape and impact angle on the impact effect of the cushioned rock shed,a modeling approach for a rock shed... Rock shed is an effective protection measure against rockfall.To investigate the influences of falling rock’s shape and impact angle on the impact effect of the cushioned rock shed,a modeling approach for a rock shed with a cushion layer using PFC-FLAC.The granular cushion is modeled as an aggregate of discrete non-cohesion particles,while the concrete plate and the beam are modeled as zones.The falling rock with different sphericities and impact angles is modeled as a rigid assembly.The numerical model is validated by comparing the simulation results with experimental and numerical results from previous literature.This model is applied to analyze the effects of rock shape and impact angle on the dynamic interaction effects between falling rock and cushioned rock shed,including the impact force,transmitted bottom force,penetration depth,and plate deflection.The numerical results show that the variation in the falling rock’s shape has different effects on the falling rock with different impact angles.These findings could support rock shed design by revealing the limitations of the assumptions in the past research,which may result in unsafe rock sheds for some rockfall cases. 展开更多
关键词 Rockfall Coupled DEM-FDM analysis Rock’s shape Impact angle Granular cushion Rock shed
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A Procedure for Trisecting an Acute Angle (Method 2)
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作者 Lyndon O. Barton 《Advances in Pure Mathematics》 2024年第4期204-213,共10页
This paper presents an alternate graphical procedure (Method 2), to that presented in earlier publications entitled, “A Procedure for Trisecting an Acute Angle” and “A Key to Solving the Angle Trisection Problem”.... This paper presents an alternate graphical procedure (Method 2), to that presented in earlier publications entitled, “A Procedure for Trisecting an Acute Angle” and “A Key to Solving the Angle Trisection Problem”. The procedure, when applied to the 30˚ and 60˚ angles that have been “proven” to be nottrisectable and the 45˚ benchmark angle that is known to be trisectable, in each case produced a construction having an identical angular relationship with Archimedes’ Construction, as in Section 2 on THEORY of this paper, where the required trisection angle was found to be one-third of its respective angle (i.e. DE’MA = 1/3 DE’CG). For example, the trisection angle for the 30˚, 45˚ and 60˚ angles were 10.00000˚, 15.00000˚, and 20.00000˚, respectively, and Section 5 on PROOF in this paper. Therefore, based on this identical angular relationship and the numerical results (i.e. to five decimal places), which represent the highest degree of accuracy and precision attainable by The Geometer’s Sketch Pad software, one can only conclude that not only the geometric requirements for arriving at an exact trisection of the 30˚ and 60˚ angle (which have been “proven” to be not-trisectable) have been met, but also, the construction is valid for any arbitrary acute angle, despite theoretical proofs to the contrary by Wantzel, Dudley, and others. 展开更多
关键词 Archimedes Construction College Geometry College Mathematics angle Trisection Famous Problems in Mathematics Mechanism Analysis Geometer’s sketch Pad
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骨性Angle′s Ⅲ类错患者正畸手术前后下颌角矢量点位置的变化及意义 被引量:1
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作者 王晨星 高振杰 陈刚 《山东医药》 CAS 北大核心 2011年第22期98-99,共2页
目的观察骨性Angle′sⅢ类错患者下颌角矢量点(Gov点)位置变化,并探讨其临床意义。方法取天津地区健康人29例为对照组,接受正手术治疗的骨性Angle′sⅢ类错畸形患者15例为观察组。均拍摄头颅侧位X线片,测量Gov点的座标。结果观察... 目的观察骨性Angle′sⅢ类错患者下颌角矢量点(Gov点)位置变化,并探讨其临床意义。方法取天津地区健康人29例为对照组,接受正手术治疗的骨性Angle′sⅢ类错畸形患者15例为观察组。均拍摄头颅侧位X线片,测量Gov点的座标。结果观察组术前、术后及对照组Gov点横坐标分别为(-4.54±0.51)、(-5.10±0.69)、(-5.02±0.35)cm,纵坐标分别为(-7.76±0.40)、(-7.65±0.57)、(-7.50±0.43)cm,观察组术前Gov点横、纵坐标与术后及对照组比较P均<0.05,观察组术后与对照组Gov点横、纵坐标比较P均>0.05。对照组下颌神经孔与Gov点间距为(1.35±0.16)cm,观察组术前为(1.27±0.19)cm,两组相比P>0.05。结论骨性Angle′sⅢ类错患者Gov点位置向前下移位,正手术后得以纠正。Gov点位置可能与下颌功能状态存在内在联系,可以作为正手术术前制定手术计划及术后评估矫治效果的指标。 展开更多
关键词 骨性anglesⅢ类错 下颌角矢量点 二维X线头影测量
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Modified viscocanalostomy in the Chinese population with open angle glaucoma: a 10-year follow-up results 被引量:3
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作者 Ya Liang Hong Sun +4 位作者 Jie Shuai Kai Xu Fang-Fang Ji Sucijanti Zhi-Lan Yuan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第3期429-435,共7页
AIM: To study the long-term efficacy and safety of modified viscocanalostomy in Chinese people with open angle glaucoma(OAG).METHODS: This retrospective study included a total of 100 eyes from 100 Chinese patients wit... AIM: To study the long-term efficacy and safety of modified viscocanalostomy in Chinese people with open angle glaucoma(OAG).METHODS: This retrospective study included a total of 100 eyes from 100 Chinese patients with medically uncontrolled OAG. All the patients underwent modified viscocanalostomy with injection of viscoelastic material in the surgically created ostia of Schlemm's canal(SC). The modifications included peeling of the inner wall of SC and the juxtacanalicular meshwork, use of mitomycin C, and loosely suturing the superficial scleral flap. Intraocular pressure(IOP), visual acuity, number of medications, laser goniopuncture data and complications were recorded. The definition of complete(qualified) success was an IOP equal to or lower than 21, 18, 16 mm Hg without(with or without) anti-glaucoma medications. RESULTS: The mean IOP was 33.5±9.9 mm Hg before surgery, 15.2±3.6 mm Hg(mean IOP reduction of 51%) at 5 y after surgery, and 15.6±2.8 mm Hg(mean IOP reduction of 49.9%) at 10 y after surgery(P<0.001). The number of anti-glaucoma medications dropped from 2.39±0.5 preoperatively to 0.47±0.8 at 5 y and 0.67±0.8 at 10 y postoperatively(P<0.001). The follow-up period was 104.5±37.0 mo. The qualified success rate for an IOP of 21, 18 or 16 mm Hg or less was 84% [95% confidence interval(CI): 0.80-0.88], 73%(95%CI: 0.68-0.78), and 59%(95%CI: 0.52-0.66) after 5 y, and 80%(95%CI: 0.76-0.84), 69%(95%CI: 0.64-0.74), 51%(95%CI: 0.44-0.58) after 10 y, respectively. There was a relationship between age, preoperative IOP and success rate(P<0.01, P<0.05). A total of 31 eyes(31.3%)in 31 patients underwent laser goniopuncture, decreasing the IOP from 22.9±4.3 mm Hg to 16.3±2.5 mm Hg(P<0.01). Neither blebitis nor endophthalmitis occurred.CONCLUSION: Modified viscocanalostomy could be performed to lower IOP, decrease multiple anti-glaucoma drops use as well. It's a safe procedure with less complications over 10 y in Chinese individuals with OAG. 展开更多
关键词 non-penetrating GLAUCOMA surgery VIsCOCANALOsTOMY schlemm’s CANAL open angle GLAUCOMA laser goniopuncture
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Elevated urine formaldehyde in elderly patients with primary open angle glaucoma 被引量:3
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作者 Ying Cui Tao Su +6 位作者 Shao-Dan Zhang Ping Huang Ying-Ge He Ying Liu Chun Zhang Robert Ritch Rong-Qiao He 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第3期411-416,共6页
AIM:To investigate the risk factor of primary open angle glaucoma(POAG),which is the leading cause of irreversible blindness worldwide.An abnormally high level of endogenous formaldehyde(FA) has recently been fou... AIM:To investigate the risk factor of primary open angle glaucoma(POAG),which is the leading cause of irreversible blindness worldwide.An abnormally high level of endogenous formaldehyde(FA) has recently been found correlated with cell death and neurodegenerative disease,raising the possibility of a putative correlation of abnormal endogenous FA with POAG.· METHODS:Thirty-four elderly patients with POAG and sixteen healthy controls were enrolled.Glaucomatous visual defects were present at both the functional(visual field) and structural[retinal nerve fiber layer(RNFL)thickness]levels.Morning urine samples were obtained and were analyzed by high-performance liquid chromatography(HPLC) to detect the endogenous FA level in a double blind manner.· RESULTS:Patients with POAG(P 〈0.05) had significantly higher urine FA levels.The urine FA level of patients with severe visual field defects[mean deviation(MD)≥12 dB]was significantly(P〈0.001) greater than that of patients with mild to moderate defects(MD〈12 dB).By optical coherence tomography(OCT),the superior and inferior RNFL thickness of POAG group was significantly(P〈0.001) thinner than in controls.Furthermore,the superior and inferior thinning of the RNFL was correlated with the elevation of urine FA concentration.CONCLUSION:Endogenous FA level is positively correlated with the neuronal defects of POAG. 展开更多
关键词 primary open angle glaucoma urineformaldehyde Alzheimer's disease
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Cytochrome P450 2E1 genetic polymorphism and gastric cancer in Changle,Fujian Province 被引量:26
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作者 Lin Cai~1 Shun-Zhang Yu~2 Zuo-Feng Zhang~3 1 Department of Epidemiology,Fujian Medical University,Fuzhou 350004,Fujian Province,China2 Department of Epidemiology,Shanghai Medical University,Shanghai 200032,China3 Department of Epidemiology,UCLA School of Public Health,Los Angeles California,USA 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第6期792-795,共4页
AIM: Genetic polymorphism in enzymes of carcinogen metabolism has been found to have the influence on the susceptibility to cancer. Cytochrome P450 2E1 (CYP2E1) is considered to play an important role in the metabolic... AIM: Genetic polymorphism in enzymes of carcinogen metabolism has been found to have the influence on the susceptibility to cancer. Cytochrome P450 2E1 (CYP2E1) is considered to play an important role in the metabolic activation of procarcinogens such as N-nitrosoamines and low molecular weight organic compounds. The purpose of this study is to determine whether CYP450 2E1 polymorphisms are associated with risks of gastric cancer. METHODS: We conducted a population based case-control study in Changle county, Fujian Province, a high-risk region of gastric cancer in China. Ninety-one incident gastric cancer patients and ninety-four healthy controls were included in our study. Datas including demographic characteristics, diet intake, and alcohol and tobacco consumption of individuals in our study were completed by a standardized questionnaire.PCR-RFLP revealed three genotypes:heterozygote (C1/C2) and two homozygotes (C1/C1 and C2/C2) in CYP2E1. RESULTS: The frequency of variant genotypes (C1/C2 and C2/C2) in gastric cancer cases and controls was 36.3% and 24.5%, respectively. The rare homozygous C2/C2 genotype was found in 6 individuals in gastric cancer group(6.6%), whereas there was only one in the control group (1.1%). However, there was no statistically significant difference between the two groups (two-tailed Fisher's exact test P=0.066). Individuals in gastric cancer group were more likely to carry genotype C1/C2 (odds ratio, OR=1.50) and C2/C2 (OR=7.34) than individuals in control group (chi(2) =4.597, for trend P=0.032). The frequencies of genotypes with the C2 allele (C1/C2 and C2/C2 genotypes) were compared with those of genotypes without C2 allele (C1/C1 genotype) among individuals in gastric cancer group and control group according to the pattern of gastric cancer risk factors. The results show that individuals who exposed to these gastric cancer risk factors and carry the C2 allele seemed to have a higher risk of developing gastric cancer. CONCLUSION: Polymorphism of CYP2E1 gene may have some effect in the development of gastric cancer in Changle county, Fujian Province. 展开更多
关键词 Polymorphism Genetic Aged Asian Continental Ancestry Group Case-Control studies China Cytochrome P-450 CYP2E1 Female Gene Frequency Genetic Predisposition to Disease Humans male Middle Aged Research support Non-U.s. Gov't stomach Neoplasms
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A Simplified Graphical Procedure for Constructing a 10˚or 20˚Angle
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作者 Lyndon O. Barton 《Advances in Pure Mathematics》 2023年第7期442-448,共7页
This paper presents a simplified graphical procedure for constructing, using an unmarked straightedge and a compass only, a 10˚ to 20˚ angle, which is in other words, trisecting a 30˚ or 60˚ angle. The procedure, when... This paper presents a simplified graphical procedure for constructing, using an unmarked straightedge and a compass only, a 10˚ to 20˚ angle, which is in other words, trisecting a 30˚ or 60˚ angle. The procedure, when applied to the 30˚ and 60˚ angles that have been “proven” to be not trisectable, produced a construction having the identical angular relationship with Archimedes’ Construction, in which the required trisection angles were found to be 10.00000˚ and 20.00000˚ respectively (i.e. exactly one-third of the given angle or ∠E’MA = 1/3∠E’CG). Based on this identical angular relationship as well as the numerical results obtained, one can only conclude that the geometric requirements for arriving at an exact trisection of the 30˚ or 60˚ angle, and therefore the construction of a 10˚ or 20˚ angle, have been met, notwithstanding the theoretical proofs of Wantzel, Dudley, and others. Thus, the solution to the age-old trisection problem, with respect to these two angles, has been accomplished. 展开更多
关键词 Archimedes Construction College Geometry angle Trisection Trisection of an angle Famous Problems in Mathematics. Geometer’s sketch Pad Mechanisms Mechanism Analysis Kinematics Trisector
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On China's Economy: A Tentative Research from a Dual Visual Angle
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作者 Guibin Suo Zhiyong Shi 《Chinese Business Review》 2005年第4期80-81,共2页
Most economists approach the economy of China from a single visual angle considering it as a special economic modality of transition economy. Based on the analysis from the single visual angle, the paper puts forward ... Most economists approach the economy of China from a single visual angle considering it as a special economic modality of transition economy. Based on the analysis from the single visual angle, the paper puts forward a dual visual angle treating China's economy as one of both transition and transformation features, and attempts to research it from this dual visual angle. 展开更多
关键词 China's economy transition and transformation dual visual angle
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The Possibility of Angle Trisection (A Compass-Straightedge Construction) Kimuya M Alex
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作者 Kimuya M Alex 《Journal of Mathematics and System Science》 2017年第1期25-42,共18页
The objective of this paper is to provide a provable solution of the ancient Greek problem of trisecting an arbitrary angle employing only compass and straightedge (ruler). (Pierre Laurent Wantzel, 1837) obscurely... The objective of this paper is to provide a provable solution of the ancient Greek problem of trisecting an arbitrary angle employing only compass and straightedge (ruler). (Pierre Laurent Wantzel, 1837) obscurely presented a proof based on ideas from Galois field showing that, the solution of angle trisection corresponds to solution of the cubic equation; x3 - 3x - 1 = 0, which is geometrically irreducible [1]. The focus of this work is to show the possibility to solve the trisection of an angle by correcting some flawed methods meant for general construction of angles, and exemplify why the stated trisection impossible proof is not geometrically valid. The revealed proof is based on a concept from the Archimedes proposition of straightedge construction [2, 3]. 展开更多
关键词 angle trisection COMPAss Ruler straightedge) Classical Construction GeoGebra software Greek's geometry Cubic equation Plane geometry solid geometry
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A Key to Solving the Angle Trisection Problem
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作者 Lyndon O. Barton 《Advances in Pure Mathematics》 2023年第9期625-634,共10页
This paper describes the methodology (or approach) that was key to the solution of the angle trisection problem published earlier in article entitled, “A Procedure For Trisecting An Acute Angle.” It was an approach ... This paper describes the methodology (or approach) that was key to the solution of the angle trisection problem published earlier in article entitled, “A Procedure For Trisecting An Acute Angle.” It was an approach that required first, designing a working model of a trisector mechanism, second, studying the motion of key elements of the mechanism and third, applying the fundamental principles of kinematics to arrive at the desired results. In presenting these results, since there was no requirement to provide a detailed analysis of the final construction, this information was not included. However, now that the publication is out, it is considered appropriate as well as instructive to explain more fully the mechanism analysis of the trisector in graphical detail, as covered in Section 3 of this paper, that formed the basis of the long sought solution to the age-old Angle Trisection Problem. 展开更多
关键词 Archimedes Construction College Geometry College Mathematics angle Trisection Trisector Famous Problems in Mathematics History of Mathematics Mechanism Analysis Kinematics Geometer’s sketch Pad
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Numerical and Experimental Study on Droplet Spreading Motion after Impingement Considering Dynamic Contact Angle with CCUP (CIP-Combined Unified Procedure) Method
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作者 Soyoun Son Gwonhyun Ko Hongsun Ryou 《Journal of Energy and Power Engineering》 2013年第1期10-16,共7页
The contact angle is one of important parameters to simulate droplet spreading and impingement phenomena on the surface. In the most numerical research, it is assumed constant value and it is implemented as boundary c... The contact angle is one of important parameters to simulate droplet spreading and impingement phenomena on the surface. In the most numerical research, it is assumed constant value and it is implemented as boundary condition. However, contact angle is changed according to contact line velocity and time. Hence, for accurate simulation, dynamic contact angle which has various values as time elapsed is adopted. In the present study, the numerical analysis is performed on the droplet spreading phenomena considering dynamic contact angle function which is obtained from single droplet spreading experiment on the flat and bare surface. The CIP (cubic interpolated pseudo-particle) method by Yabe is used for analysis of interface between liquid and gas phases. The numerical results considering contact angle function which newly modeled as time and contact angle are compared with numerical results considering Hoffman's function and experimental data for range of Weber number which are 4.427 and 11.334. In contrast of numerical result considering Hoffman's function, the numerical result shows good agreement with experimental data as time elapsed in contact angle evolution, deformation of droplet spreading radius and height. Indeed, overall, the results display the increasing maximum spreading radius and the decreasing height as Weber numbers increased. 展开更多
关键词 CIP method droplet spreading height droplet spreading radius dynamic contact angle Hoffman's fimction.
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Clinical significance of Baumann's angle in the percutaneous pinning fixation for supracondylar fractures of the humerus in children
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作者 孔建中 《外科研究与新技术》 2005年第3期174-174,共1页
To evaluate the clinical significance of Baumann’s angle in the closed reduction and percutaneous pinning fixation for supracondylar fractures of the humerus in children.Methods There were 97 children (male 59,female... To evaluate the clinical significance of Baumann’s angle in the closed reduction and percutaneous pinning fixation for supracondylar fractures of the humerus in children.Methods There were 97 children (male 59,female 38,mean age of 6.8 years) with displaced supracondylar fracrtures of the humerus were treated in this hospital.Under fluoroscopy guidance,three-dimensional displacement of fractures was corrected by closed reduction.The percutaneous Kirschner wire pinning was applied only if the radiographs demonstrated that Baumann’s angle was less than 4 degree compared to that on the normal side.All of them were followed up for 34.5 months (range,12 to 48 months).Results There was one case with ulnar nerve palsy associated with the pinning.There were no Volkmann’s contracture in this group.X-ray examinations revealed an average 73.7 degrees of Baumann angle on the injured and 72.8 on uninjured side.An average 7.6 degrees of the carrying angle on the injured and 9.7 on uninjured side were also demonstrated by radiography.Five patients developed slight cubitus varus deformity.The result according to Flynn criteria were excellent in 85 patients (87.6%),good in 12 patients (12.4%).Conclusion The satisfactory results can be gained in children with displaced supracondylar fractures of the humerus by restoration of the normal Baumann angle and percutaneous pinning fixation.18 refs,2 figs. 展开更多
关键词 Clinical significance of Baumann’s angle in the percutaneous pinning fixation for supracondylar fractures of the humerus in children
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Comparative Studies on the Changes of Microtubule Distribution and Reorganization During the Meiotic Stages of Development in Normal (IR36) and a Temperature/photoperiod Sensitive Male Sterile Line (Peiai 64S) of Rice ( Oryza sativa ) 被引量:3
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作者 徐是雄 刘向东 +1 位作者 冯九焕 卢永根 《Acta Botanica Sinica》 CSCD 2001年第3期221-226,共6页
Changes in the pattern of organization of microtubules in the meiotic stages of development of pollen (i.e. from pre-meiotic interphase to more or less metaphase I) of a normal (IR36) and a temperature/photoperiod sen... Changes in the pattern of organization of microtubules in the meiotic stages of development of pollen (i.e. from pre-meiotic interphase to more or less metaphase I) of a normal (IR36) and a temperature/photoperiod sensitive male sterile line (Peiai 64S) of rice were studied using immunofluorescence confocal microscopy. In IR36, from pre-meiotic interphase to metaphase I, the pattern of microtubule distribution in the meiocytes underwent a series of changes. Some new organizational patterns of microtubules (that have not been described before) were observed during microsporogenesis, including the existence of a broad band of perinuclear microtubules at the diakinesis stage of development. The pattern of microtubule distribution in the meiocytes of the male sterile line, Peiai 64S, was quite different front that seen in IR36. In Peiai 64S, the microtubules showed abnormal patterns of distribution from pre-meiotic interphase to metaphase I. For example the broad band of perinuclear microtubules seen at diakinesis in IR36 was much disorganized and loosened in Peiai 64S. The spindles formed were also very abnormal and different from the normal spindle. The appearance of abnormal microtubule distribution in the early stages of microsporogenesis may contribute to the malformation and ultimate abortion of pollen in Peiai 64S. 展开更多
关键词 Oryza sativa temperature/photoperiod sensitive male sterile rice line microtubules Peiai 64s IR36 microsporocyte meiosis microsporogenesis
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Characterization of Reverse Thermo-sensitive Genic Male Sterile Lines in Cold Regions of China
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作者 高扬 谭炎宁 +2 位作者 孟昭河 段美娟 徐秋生 《Agricultural Science & Technology》 CAS 2017年第7期1183-1186,1201,共5页
Yannong S, a reverse thermo-sensitive genic male sterile (TGMS) line, is sterile at high temperature and fertile at low temperature. In the present study, the fertility of Yannong S and the japonica reverse TGMS lin... Yannong S, a reverse thermo-sensitive genic male sterile (TGMS) line, is sterile at high temperature and fertile at low temperature. In the present study, the fertility of Yannong S and the japonica reverse TGMS lines derived from it was in- vestigated in Harbin, Heilongjiang from 2013 to 2015. The results showed that Yan- nong S was completely male sterile in July and August (the hottest months of the year in Harbin), and the seed setting rate of bagged panicles was 0. We also in- ferred that the critical temperature for inducing the sterility of Yannong S was higher than 28 ℃. Most of the japonica reverse TGMS lines derived from Yannong S were completely aborted in July and August, with a seed setting rate of 0. It can be con- cluded that the reverse TGMS lines derived from Yannong S are genetically stable lines that have a long period of sterility in cold regions, so they may be the ideal genetic materials for the development and in-situ seed production of japonica hybrid rice. 展开更多
关键词 Japonica hybrid rice Reverse thermo-sensitive genic male sterile lines Cold regions Yannong s FERTILITY
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Recent advances in identification of male specificity determinant and its function in S-RNase-mediated gametophytic self-incompatibility
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作者 张琳 谭晓风 乌云塔娜 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期124-128,共5页
S-RNase-mediated gametophytic self-incompatibility (GSI) is controlled by a multiallelic S-locus at which two separate genes, the female (pistil) and male (pollen) specificity determinants, are tightly linked. T... S-RNase-mediated gametophytic self-incompatibility (GSI) is controlled by a multiallelic S-locus at which two separate genes, the female (pistil) and male (pollen) specificity determinants, are tightly linked. This review described both the identification of pollen specific F-box genes, SLF/SFBs, in Antirrhinum, Petunia and Prunus species and the demonstration of SLF/SFB as pollen determinant together with their functions in GSI response. Recent studies of how the pollen determinant functions in pollination reaction revealed that pollen determinant interacted with S-RNases in a non-allele-specific manner. It targeted all of the non-self S-RNases for ubiquitination through a functional SCF complex and subsequent degradation via 26S proteasome pathway in compatible reaction. It allows pollen tube to reach into the embryo sac and to finish double fertilization. In incompatible response, the intact self S-RNases were left to function as a cytotoxin that degrades self-pollen tube RNA, resulting in the cessation of pollen tube growth. 展开更多
关键词 Gametophytic self-incompatibility Pollen specific F-box genes male determinant sCF complex 26s proteasome pathway
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Norepinephrine transporter (NET) is expressed in cardiac sympathetic ganglia of adult rat 被引量:41
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作者 LiH MaSK 《Cell Research》 SCIE CAS CSCD 2001年第4期317-320,共4页
The sympathetic nervous system plays a cardinal role in regulating cardiac function through releasing the neurotransmitter norepinephrine (NE). In comparison with central nervous system, the molecular mechanism of NE ... The sympathetic nervous system plays a cardinal role in regulating cardiac function through releasing the neurotransmitter norepinephrine (NE). In comparison with central nervous system, the molecular mechanism of NE uptake in myocardium is not clear. In present study, we proved that in rat the CNS type of NE transporter (NET) was also expressed in middle cervical-stellate ganglion complex (MC-SG complex) which is considered to control the activity of heart, but not expressed in myocardium. The results also showed that NET expression level in right ganglion was significantly higher than in the left, rendering the greater capacity of NE uptake in right ventricle, a fact which may contribute to the maintenance of right ventricular function under pathologic state. 展开更多
关键词 Animals Heart male MYOCARDIUM Norepinephrine Plasma Membrane Transport Proteins RNA Messenger RATs Rats sprague-Dawley Research support Non-U.s. Gov't stellate Ganglion symporters
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Effects of progesterone on gastric emptying and intestinal transit in male rats 被引量:14
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作者 Paulus S.Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期338-341,共4页
AIM: To study the dose-dependent of progesterone (P) effect and the interaction between the oxytocin (OT) and P on gastrointestinal motility. METHODS: In order to monitor the gastric emptying and intestinal transit, t... AIM: To study the dose-dependent of progesterone (P) effect and the interaction between the oxytocin (OT) and P on gastrointestinal motility. METHODS: In order to monitor the gastric emptying and intestinal transit, the SD male rats were intubated via a catheter with normal saline (3 ml/kg) containing Na(2)(51)CrO(4) (0.5 microCi/ml) and 10% charcoal. OT was dissolved into normal saline and P was dissolved into 75% alcohol. RESULTS: Low does of P (1 mg/kg, i.p.) enhanced the gastric emptying (75+/-3%, P【0.05) and high dose of P (5 mg/kg, i.p.) inhibit it (42+/-11.2%, P【0.01). P (1 mg/kg) increased the intestinal transit (4.2+/-0.3, P【0.05) while the higher dose (10-20 mg/kg) had no effect. OT (0.8 mg/kg, i.p.) inhibited the gastric emptying (23.5+/-9.8%, P【0.01). The inhibitory effects of P(20 mg/kg) (32+/-9.7%, P【0.05) and OT (0.8 mg/kg) on gastric emptying enhanced each other when the two chemicals were administrated simultaneously (17+/-9.4%, P【0.01). CONCLUSION: Low dose of P increased GI motility while high dose of P decreased it. During the later period of pregnancy, elevated plasma level of OT may also participate in the gastrointestinal inhibition. 展开更多
关键词 ANIMALs Drug Interactions Gastric Emptying Gastrointestinal Transit male OXYTOCIN PROGEsTERONE Random Allocation RATs Rats sprague-Dawley Research support Non-U.s. Gov't
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PCR analysis of Yq microdeletions in infertile males, a study from South India 被引量:9
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作者 S. Ramesh Babu M. Swarna +1 位作者 P. Padmavathi P.P. Reddy 《Asian Journal of Andrology》 SCIE CAS CSCD 2002年第4期265-268,共4页
AIM: To estimate the frequency of microdeletions in the long arm of Y-chromosome of 20 infertile males from South India. METHODS: Polymerase chain reaction (PCR) amplification using Y-specific STS of azoospermia facto... AIM: To estimate the frequency of microdeletions in the long arm of Y-chromosome of 20 infertile males from South India. METHODS: Polymerase chain reaction (PCR) amplification using Y-specific STS of azoospermia factor (AZF) regions i.e., SY 84 for AZFa, SY 127 for AZFb and SY 254 for AZFc. RESULTS: Of the 20 infertile subjects 3 (15 %), one azoospermic and two oligozoospermic, showed microdeletions in the AZF region of Y-chromosome. CONCLUSION: The frequency of deletions involving AZF region of the Y-chromosome is 15 % in azoospermic and severely oligozoospermic infertile men. PCR amplification of AZF locus is useful for the diagnosis of microdeletions in the Y-chromosome. 展开更多
关键词 Chromosome Deletion Chromosomes Human Y Base sequence Chromosome Mapping Comparative study DNA Primers Female Gene Frequency Humans India Infertility male male OLIGOsPERMIA Polymerase Chain Reaction Reference Values Research support Non-U.s. Gov't seminal Plasma Proteins
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水稻散生与部分雄性不育突变体lpms1的鉴定与基因定位
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作者 周慧 林祯芃 +5 位作者 常志远 周海平 王成豹 钟林平 徐秀如 马国华 《核农学报》 CAS CSCD 北大核心 2024年第12期2270-2280,共11页
水稻分蘖角度是构建理想株型的关键因素,雄性不育株系是杂交水稻育种的重要种质资源。为进一步解析分蘖角度和花粉发育的调控机制,本研究通过农艺性状调查、育性检测、扫描和透射电镜观察等方法,比较野生型S40和经甲基磺酸乙酯(EMS)诱... 水稻分蘖角度是构建理想株型的关键因素,雄性不育株系是杂交水稻育种的重要种质资源。为进一步解析分蘖角度和花粉发育的调控机制,本研究通过农艺性状调查、育性检测、扫描和透射电镜观察等方法,比较野生型S40和经甲基磺酸乙酯(EMS)诱变得到的散生雄性不育突变体lpms1(lazy and partially male sterile 1)的表型差异。结果表明,与野生型相比,lpms1突变体的分蘖角度增大,育性降低,并伴随株高、粒长、穗粒数、结实率和千粒重等重要性状不同程度降低。扫描和透射电镜观察到lpms1的成熟花粉粒表面皱缩、空瘪,内容物不充实,花粉壁异常。实时荧光定量PCR(q RT-PCR)结果显示,lpms1突变会引起花粉发育相关基因的表达发生差异。遗传分析结果表明,lpms1是单基因隐性突变。利用株型紧凑材料与lpms1杂交构建F_(2)群体,结合分离群体分组分析测序方法(BSA-seq)和图位克隆方法进行基因定位。最终,LPMS1基因定位于第5号染色体插入缺失(Indel)标记A3与A4之间298 kb的范围内,该区间有38个开放阅读框(ORFs),但无分蘖角度和花粉发育相关基因报道。LPMS1是新的分蘖角度和花粉发育基因,该基因突变会同时引起水稻分蘖角度增加、育性降低。本研究结果为水稻分蘖角度和花粉发育的调控机制研究以及水稻株型和育性改良种质的创制提供了新的遗传资源。 展开更多
关键词 水稻 突变体 分蘖角度 雄性不育 基因定位
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Effects of Cow’s Milk on Reproduction in ICR Male Mice
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作者 YU-XIA MA NAOYUKI EBINE +2 位作者 KAZUO AOKI MASAHIRO KUSUNOKI AND JUNICHI MISUMI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第2期161-163,共3页
Objective To study the effects of Cow's milk on the reproduction in male mice. Methods Twenty-four male mice were divided randomly into two groups: milk group (M) and control group (C). Each mouse was given 10 m... Objective To study the effects of Cow's milk on the reproduction in male mice. Methods Twenty-four male mice were divided randomly into two groups: milk group (M) and control group (C). Each mouse was given 10 mL milk per day from 4 to 16 weeks in the group M. At the age of 17 weeks, all the mice were sacrificed. Results Serum testosterone was decreased in the group M (P=0.037). No significant difference was found in weight of testes, seminal vesicle or adrenal gland of mice between the groups C and M. However, the weight of seminal vesicle decreased when expressed in g/100 g body weight in the group M. Epididymal sperm concentration, motility, morphology, and sperm head number were not affected by milk. Conclusion Cow's milk has adverse effects on the reproductive system in ICR male mice. Further studies are needed to clarify the specific effects of milk on reproductive health. 展开更多
关键词 Cow's milk male mice Reproductive health
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