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Eagle’s Syndrome: A Case Report of a Bilateral Elongated Styloid Process
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作者 Mahammad Davudov Surayya Isgandarova Parvin Hasanova 《International Journal of Otolaryngology and Head & Neck Surgery》 2023年第6期405-410,共6页
Eagle’s syndrome is symptomatic of the styloid process (SP) elongation or calcification of the stylohyoid and stylomandibular ligaments. As a result of Eagle’s various studies, 4 out of every 100 patients showed tha... Eagle’s syndrome is symptomatic of the styloid process (SP) elongation or calcification of the stylohyoid and stylomandibular ligaments. As a result of Eagle’s various studies, 4 out of every 100 patients showed that the styloid process was long. However only 4% of these cases are symptomatic [1]. Surgical traumas such as tonsillectomy or stylomandibular chronic irritation of the ligament, proc. of styloideusosteitis, ossifying periosteitis, tendinitis or mucositis why could it be [2]. The main symptoms are facial pain, dysphagia, sore throat, earache and headache. It may be unilateral or bilateral. The styloid process can be shortened through an intraoral or external approach. The case of Eagle syndrome in a 39-year-old female patient who was diagnosed to have bilateral elongated. 展开更多
关键词 Eagle’s Syndrome Throat Pain elongated Styloid Process Extraoral Approach
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Muco-submucosal elongated polyps of the gastrointestinal tract:A case series and a review of the literature 被引量:2
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作者 Char Loo Tan Sze Hwa Tan +1 位作者 Jimmy BY So Fredrik Petersson 《World Journal of Gastroenterology》 SCIE CAS 2013年第11期1845-1849,共5页
We present three cases of gastrointestinal muco-submucosal elongated polyps,two located in the duodenum and one in the descending colon.All three cases had a characteristic,"worm-like" endoscopic appearance ... We present three cases of gastrointestinal muco-submucosal elongated polyps,two located in the duodenum and one in the descending colon.All three cases had a characteristic,"worm-like" endoscopic appearance and were lined by unremarkable mucosa.The vascular component was located in the submucosa and was composed of a mixture of variably dilated blood vessels(capillaries and veins) and lymphatics.The duodenal polyps displayed lipomatous metaplasia of the submucosal stroma.The dual vascular phenotype of the vascular component was confirmed by immunohistochemistry with D2-40 and CD31. 展开更多
关键词 Muco-submucosal elongated POLYP Vascular MALFORMATION Endoscopic ultrasonography ANGIOMA Endoscopy
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Experimental study of gas-water elongated bubble flow during production logging 被引量:1
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作者 Lu Jing Wu Xiling 《Petroleum Science》 SCIE CAS CSCD 2011年第2期157-162,共6页
In order to improve the interpretation of production log data on gas-water elongated bubble (EB) flow in horizontal wells, a multi-phase flow simulation device was set up to conduct a series of measurement experimen... In order to improve the interpretation of production log data on gas-water elongated bubble (EB) flow in horizontal wells, a multi-phase flow simulation device was set up to conduct a series of measurement experiments using air and tap water as test media, which were measured using a real production logging tool (PLT) string at different deviations and in different mixed flow states. By understanding the characteristics and mechanisms of gas-water EB flow in transparent experimental boreholes during production logging, combined with an analysis of the production log response characteristics and experimental production logging flow pattern maps, a method for flow pattern identification relying on log responses and a drift-flux model were proposed for gas-water EB flow. This model, built upon experimental data of EB flow, reveals physical mechanisms of gas-water EB flow during measurement processing. The coefficients it contains are the specific values under experimental conditions and with the PLT string used in our experiments. These coefficients also reveal the interference with original downhole flow patterns by the PLT string. Due to the representativeness that our simulated flow experiments and PLT string possess, the model coefficients can be applied as empirical values of logging interpretation model parameters directly to real production logging data interpretation, when the measurement circumstances and PLT strings are similar. 展开更多
关键词 Horizontal wells elongated bubble flow flow patterns identification drift-flux model logging interpretation model
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Generalized flyby trajectories around elongated minor celestial bodies as a rotating mass dipole 被引量:3
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作者 Xiangyuan Zeng Baodong Fang +1 位作者 Junfeng Li Yang Yu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第3期535-545,共11页
The aim of this paper is to understand the common characteristics of the generalized flyby trajectory around natural elongated bodies. Such flyby trajectories provide a short-term mechanism to clear away vicinal objec... The aim of this paper is to understand the common characteristics of the generalized flyby trajectory around natural elongated bodies. Such flyby trajectories provide a short-term mechanism to clear away vicinal objects or temporally capture ejecta into circling orbits. The gravitational potential of elongated bodies is described by a unified approximate model, i.e., the rotating mass dipole which is two point masses connected with a constant massless rod The energy power is used to illustrate the flyby effect in terms of the instantaneous orbital energy. The essential of the single flyby trajectory is studied analytically, and the relationship between the flyby trajectory and its Jacobi integral is also illustrated. Sample trajectories are given to show the variational trend of the energy increment with respect to differen orbital periapsides. The distribution of natural ejecting orbits is presented by varying the parameters of the approximate model. 展开更多
关键词 Generalized flyby trajectory Natural elongated body Rotating mass dipole Natural ejecting orbits
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Generating Periodic Orbits for Explorations of Elongated Asteroids
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作者 Huihui Wang Yuntao Jiang +1 位作者 Long Xiao Yonglong Zhang 《Journal of Beijing Institute of Technology》 EI CAS 2020年第1期129-138,共10页
A practical method is proposed to search for periodic orbits of elongated asteroids.The method obtains required initial variables of periodic orbits by using the rotating mass dipole with appropriate parameters,and th... A practical method is proposed to search for periodic orbits of elongated asteroids.The method obtains required initial variables of periodic orbits by using the rotating mass dipole with appropriate parameters,and then implement local iterations to obtain the real orbits over an asteroid in the polyhedral model.In this paper the dipole and polyhedral models,and list detailed procedures of the searching method are introduced.A planar single lobe orbit is presented to evaluate the effectiveness of the method,with the asteroid 216 Kleopatra of the triple asteroid system as a representative elongated body.By applying the above method,ten families of periodic orbits around Kleopatra are identified and discussed with respect to their orbital stabilities and periods.One sample of the sombrero orbit is checked by calculating 1000 hours to examine its orbital behavior.Besides the above orbits,the intriguing head-surrounding orbit is also analyzed. 展开更多
关键词 periodic ORBITS elongated ASTEROIDS DIPOLE model numerical ITERATION
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ELONGATED-NEEDLE TREATMENT OF URINARY INCONTINENCE CAUSED BY APOPLEXY
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作者 张闻东 许能贵 董赟 《World Journal of Acupuncture-Moxibustion》 1996年第2期33-35,共3页
In the present paper, the effect of deep insertion of elongated needle onto pelvic nerve(pelvic plexus) for treatment of 32 cases of urinary incontinence caused by apoplexy was observed andcompared to that of filiform... In the present paper, the effect of deep insertion of elongated needle onto pelvic nerve(pelvic plexus) for treatment of 32 cases of urinary incontinence caused by apoplexy was observed andcompared to that of filiform needle group (25 cases). Results showed that the total effective rates ofthe elongated needle group and the filiform needle group were 96. 88 % and 68 % respectively, display-ing a significant difference (P【0.05) between the two groups. In addition, mechanisms of elongatedneedle in treatment of incontinence of urine were analyzed preliminarily. 展开更多
关键词 elongated NEEDLE CEREBRAL APOPLEXY INCONTINENCE of URINE
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TREATMENT OF 67 CASES OF GASTROPTOSIS WITH ELONGATED NEEDLE(芒针)
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作者 张连良 《World Journal of Acupuncture-Moxibustion》 1996年第2期3-6,共4页
Sixty-seven patients with gastroptosis were treated by stimulating Guanmen (ST 22)and Taiyi (ST 23) acupoints with elongated needles, obtaining a satisfactory result. Of them, 52 caseswere cured, 7 cases markedly effe... Sixty-seven patients with gastroptosis were treated by stimulating Guanmen (ST 22)and Taiyi (ST 23) acupoints with elongated needles, obtaining a satisfactory result. Of them, 52 caseswere cured, 7 cases markedly effective and 8 cases ineffective. The total effective rate was 88%. 展开更多
关键词 GASTROPTOSIS elongated NEEDLE THERAPY Guanmen and TAIYI ACUPOINTS
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CLINICAL OBSERVATION ON 540 CASES OF GASTROPTOSIS TREATED WITH ELONGATED NEEDLE
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作者 葛书翰 葛继魁 《World Journal of Acupuncture-Moxibustion》 1999年第3期20-24,共5页
Point penetration method by elongated needle and lifting manipulation were adopted totreat gastroptosis, getting marked effect. In this series of 540 cases, the cure rate was 40. 7 % and thetotal effective rate was 90... Point penetration method by elongated needle and lifting manipulation were adopted totreat gastroptosis, getting marked effect. In this series of 540 cases, the cure rate was 40. 7 % and thetotal effective rate was 90. 7 %. There was a close relationship between the therapeutic effect and thedegree of gastroptosis, the cure rate of I° gastroptosis was 77. 6%, while that of Ⅲ° gastroptosis wasonly 11. 8 %. There was a very significant difference between them(P < 0. 001 ) 展开更多
关键词 GASTROPTOSIS elongated NEEDLE POINT PENETRATION method
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Incidental Finding of an Elongated Styloid Process during Tonsillectomy Procedure
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作者 Loay Al-Ekri Abdulkarim Alsaei 《International Journal of Otolaryngology and Head & Neck Surgery》 2015年第3期236-240,共5页
Patients with recurrent throat pain, dysphagia, or facial pain symptoms might have Eagle’s syndrome due to abnormal length of the styloid process or calcification of stylohyoid ligament complex. In adults, the styloi... Patients with recurrent throat pain, dysphagia, or facial pain symptoms might have Eagle’s syndrome due to abnormal length of the styloid process or calcification of stylohyoid ligament complex. In adults, the styloid process is approximately 2.5 cm long. The etiology of this disease is not well understood, and usually asymptomatic. In some cases, the styloid tip, which is located between the external and internal carotid arteries, compresses the perivascular sympathetic fibers, resulting in a persistent pain. The disease can be diagnosed by physical examination through digital palpation of the styloid process in the tonsillar fossa or by radiographic workup that includes anterior-posterior and lateral skull films. We report a 33-year-old woman with an incidental finding of an elongated styloid process during a routine tonsillectomy procedure. 展开更多
关键词 elongated Styloid PROCESS Eagle’s SYNDROME
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Screening for Rice Germplasms with Specially-Elongated Mesocotyl 被引量:6
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作者 Wu Ming-guo ZHANG Guang-heng LIN Jian-rong CHENG Shi-hua 《Rice science》 SCIE 2005年第3期226-228,共3页
The lengths of mesocotyl in the seedlings of 84 lowland rice varieties and 12 upland rice varieties were measured following the treatments of daylight and darkness during germination. The elongation of mesocotyl in th... The lengths of mesocotyl in the seedlings of 84 lowland rice varieties and 12 upland rice varieties were measured following the treatments of daylight and darkness during germination. The elongation of mesocotyl in the varieties tested was inhibited under daylight condition, and the mesocotyl of all the varieties elongated variably under darkness condition. The elongated lengths of the mesocotyl in upland rice, ranging from 0.36 cm to 1,61 cm with an average of 0.81 cm, was obviously longer than those in lowland rice, ranging from 0.12 cm to 1.56 cm with an average of 0.42 cm. Among 14 rice varieties with over 1 cm of mesocotyl length, five belonged to upland rice, and nine to lowland rice. The possible utilization of the elongated-mesocotyl rice germplasm in varietal imorovement, direct-seeded plantina and seed ouritv testina were discussed. 展开更多
关键词 mesocotyl elongation SCREENING GERMPLASM RICE
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On-board modeling of gravity fields of elongated asteroids using Hopfield neural networks
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作者 Yingjie Zhao Hongwei Yang +1 位作者 Shuang Li Yirong Zhou 《Astrodynamics》 EI CSCD 2023年第1期101-114,共14页
To rapidly model the gravity field near elongated asteroids,an intelligent inversion method using Hopfield neural networks(HNNs)is proposed to estimate on-orbit simplified model parameters.First,based on a rotating ma... To rapidly model the gravity field near elongated asteroids,an intelligent inversion method using Hopfield neural networks(HNNs)is proposed to estimate on-orbit simplified model parameters.First,based on a rotating mass dipole model,the gravitational field of asteroids is characterized using a few parameters.To solve all the parameters of this simplified model,a stepped parameter estimation model is constructed based on different gravity field models.Second,to overcome linearization difficulties caused by the coupling of the parameters to be estimated and the system state,a dynamic parameter linearization technique is proposed such that all terms except the parameter terms are known or available.Moreover,the Lyapunov function of the HNNs is matched to the problem of minimizing parameter estimation errors.Equilibrium values of the Lyapunov function areused as estimated values.The proposed method is applied to natural elongated asteroids 216 Kleopatra,951 Gaspra,and 433 Eros.Simulation results indicate that this method can estimate the simplified model parameters rapidly,and that the estimated simplified model provides a good approximation of the gravity field of elongated asteroids. 展开更多
关键词 elongated asteroids simplified model Hopfield neural networks(HNNs) on-board learning gravity inversion
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Resonant orbit search and stability analysis for elongated asteroids
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作者 Yu-Hang Zhang Ying-Jing Qian +1 位作者 Xu Li Xiao-Dong Yang 《Astrodynamics》 EI CSCD 2023年第1期51-67,共17页
Periodic orbits are crucial in facilitating the understanding of the dynamical behavior of elongated asteroids.As a specific type of periodic orbit,resonant orbits can enrich the orbit design method of deep-space expl... Periodic orbits are crucial in facilitating the understanding of the dynamical behavior of elongated asteroids.As a specific type of periodic orbit,resonant orbits can enrich the orbit design method of deep-space exploration missions.Herein,a dipole segment model for investigating the orbital dynamics of elongated asteroids is briefly introduced.A new numerical algorithm named the modified path searching method for identifying spin-orbit resonant orbits is proposed.Using the modified path searching and pseudo-arclength continuation methods,four spin-orbit resonant families for asteroid 2063 Bacchus are obtained.The distribution of eigenvalues and stability curves for the four resonant families are presented.In particular,some critical points corresponding to period-doubling and tangent bifurcations appear in the stability curves. 展开更多
关键词 elongated asteroid dipole segment model spin-orbit resonant orbits stability
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Study of micro-elongated thermoelastic medium loaded with a piezoelectric layer under the influence of gravity using the dual-phase-lag model
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作者 Mohamed I.A.Othman Ebtesam E.M.Eraki Mohamed F.Ismail 《International Journal of Mechanical System Dynamics》 2023年第2期136-145,共10页
This paper aims to examine the influence of gravity on a thermoelastic microelongated layer when a piezoelectric layer is above it,utilizing the theory of Lord–Shulman(L–S)and also the model of dual‐phase‐lag(DPL)... This paper aims to examine the influence of gravity on a thermoelastic microelongated layer when a piezoelectric layer is above it,utilizing the theory of Lord–Shulman(L–S)and also the model of dual‐phase‐lag(DPL).A partial differential equation was transformed into an ordinary differential equation using the normal mode analysis.Aluminum epoxy numerical computations are carried out,and the results are presented in graphical format.The L–S theory and the model of DPL are compared in the presence and absence of gravity and it is found that gravity has quite a massive influence on all the physical quantities. 展开更多
关键词 PIEZOELECTRICS normal mode analysis GRAVITY micro‐elongated thermoelastic DPL model
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Chemokine platelet factor 4 accelerates peripheral nerve regeneration by regulating Schwann cell activation and axon elongation 被引量:1
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作者 Miao Gu Xiao Cheng +3 位作者 Di Zhang Weiyan Wu Yi Cao Jianghong He 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期190-195,共6页
Schwann cells in peripheral nerves react to traumatic nerve injury by attempting to grow and regenerate.Howeve r,it is unclear what factors play a role in this process.In this study,we searched a GEO database and foun... Schwann cells in peripheral nerves react to traumatic nerve injury by attempting to grow and regenerate.Howeve r,it is unclear what factors play a role in this process.In this study,we searched a GEO database and found that expression of platelet factor 4 was markedly up-regulated after sciatic nerve injury.Platelet factor is an important molecule in cell apoptosis,diffe rentiation,survival,and proliferation.Further,polymerase chain reaction and immunohistochemical staining confirmed the change in platelet factor 4 in the sciatic nerve at different time points after injury.Enzyme-linked immunosorbent assay confirmed that platelet factor 4 was secreted by Schwann cells.We also found that silencing platelet factor 4 decreased the proliferation and migration of primary cultured Schwann cells,while exogenously applied platelet factor 4 stimulated Schwann cell prolife ration and migration and neuronal axon growth.Furthermore,knocking out platelet factor 4 inhibited the prolife ration of Schwann cells in injured rat sciatic nerve.These findings suggest that Schwann cell-secreted platelet factor 4 may facilitate peripheral nerve repair and regeneration by regulating Schwann cell activation and axon growth.Thus,platelet factor 4 may be a potential therapeutic target for traumatic peripheral nerve injury. 展开更多
关键词 axon elongation bioinformatic analysis cell migration cell proliferation dorsal root ganglia peripheral nerve regeneration peripheral nerve trauma platelet factor 4 rat sciatic nerve Schwann cells
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High toughness alumina ceramics with elongated grains developed from seeds 被引量:1
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作者 谢志鹏 高立春 +2 位作者 李文超 徐利华 王习东 《Science China(Technological Sciences)》 SCIE EI CAS 2003年第5期527-536,共10页
In the present paper, the influence of a-Al2O3 seeds and sintering methods on elongated grain growth and fracture toughness is investigated. The preparation of alumina ceramics started with commercial aluminum hydroxi... In the present paper, the influence of a-Al2O3 seeds and sintering methods on elongated grain growth and fracture toughness is investigated. The preparation of alumina ceramics started with commercial aluminum hydroxide. Abrasives were introduced to the starting materials by wet-grinding of high-purity alumina milling balls. Abrasives, playing the role of seeds, lowered the transformation temperature of aluminum hydroxide to alumina. Microstructures with elongated grains were developed by hot-pressing for the above calcined powders containing a-Al2O3 seeds, and alumina grain shapes changed with the amount of seeds introduced. However, only equiaxed grains were observed for the samples pressureless sintered. Fracture toughness of the alumina ceramics was dramatically improved by elongated grains. For the sample hot-pressed at 1600℃ for 2 h under 40 MPa pressure, fracture toughness reached 7.1 MPam1/2, which is much higher than that of normal alumina ceramics without elongated grains. In addition, high flexural strength of 630 MPa for the hot-pressed samples was also obtained. 展开更多
关键词 ALUMINA elongated grains Α-AL2O3 seeds aluminum hydroxide fracture toughness.
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A rice mutant displaying a heterochronically elongated internode carries a 100 kb deletion 被引量:1
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作者 Mika Hayashi-Tsugane Masahiko Maekawa +3 位作者 Qian Qian Hirokazu Kobayashi Shigeru Iida Kazuo Tsugane 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2011年第3期123-128,共6页
We have isolated a recessive rice mutant, designated as indeterminate growth (ing), which displays creeping and apparent heterochronic phenotypes in the vegetative period with lanky and winding culms. Rough mapping ... We have isolated a recessive rice mutant, designated as indeterminate growth (ing), which displays creeping and apparent heterochronic phenotypes in the vegetative period with lanky and winding culms. Rough mapping and subsequent molecular characterization revealed that the ing mutant carries a large deletion, which corresponds to a 103 kb region in the Nipponbare genome, containing nine annotated genes on chromosome 3. Of these annotated genes, the SLR1 gene encoding a DELLA protein is the only one that is well characterized in its function, and its null mutation, which is caused by a single base deletion in the middle of the intronless SLR1 gene, confers a slender phenotype that bears close resemblance to the ing mutant phenotype. The primary cause of the ing mutant phenotype is the deletion of the SLR1 gene, and the ing mutant appears to be the first characterized mutant having the entire SLR1 sequence deleted. Our results also suggest that the deleted region of 103 kb does not contain an indispensable gene, whose dysfunction must result in a lethal phenotype. 展开更多
关键词 Heterochronic elongated intemode Large deletion Map-based cloning Rice genome
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Candidate genes conferring ethylene-response in cultivated peanuts determined by BSA-seq and fine-mapping
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作者 Yanyan Tang Zhong Huang +6 位作者 Shaohui Xu Wenjie Zhou Jianjun Ren Fuxin Yu Jingshan Wang Wujun Ma Lixian Qiao 《The Crop Journal》 SCIE CSCD 2024年第3期856-865,共10页
Ethylene plays essential roles in plant growth,development and stress responses.The ethylene signaling pathway and molecular mechanism have been studied extensively in Arabidopsis and rice but limited in peanuts.Here,... Ethylene plays essential roles in plant growth,development and stress responses.The ethylene signaling pathway and molecular mechanism have been studied extensively in Arabidopsis and rice but limited in peanuts.Here,we established a sand-culture method to screen pingyangmycin mutagenized peanut lines based on their specific response to ethylene(“triple response”).An ethylene-insensitive mutant,inhibition of peanut hypocotyl elongation 1(iph1),was identified that showed reduced sensitivity to ethylene in both hypocotyl elongation and root growth.Through bulked segregant analysis sequencing,a major gene related to iph1,named AhIPH1,was preliminarily mapped at the chromosome Arahy.01,and further narrowed to a 450-kb genomic region through substitution mapping strategy.A total of 7014 genes were differentially expressed among the ACC treatment through RNA-seq analysis,of which only the Arahy.5BLU0Q gene in the candidate mapping interval was differentially expressed between WT and mutant iph1.Integrating sequence variations,functional annotation and transcriptome analysis revealed that a predicated gene,Arahy.5BLU0Q,encoding SNF1 protein kinase,may be the candidate gene for AhIPH1.This gene contained two single-nucleotide polymorphisms at promoter region and was more highly expressed in iph1 than WT.Our findings reveal a novel ethylene-responsive gene,which provides a theoretical foundation and new genetic resources for the mechanism of ethylene signaling in peanuts. 展开更多
关键词 Ethylene-insensitive Hypocotyl elongation AhIPH1 Candidate gene Genetic resources
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Strigolactones modulate cotton fiber elongation and secondary cell wall thickening
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作者 Yunze Wen Peng He +3 位作者 Xiaohan Bai Huizhi Zhang Yunfeng Zhang Jianing Yu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1850-1863,共14页
Cotton is one of the most important economic crops in the world,and it is a major source of fiber in the textile industry.Strigolactones(SLs)are a class of carotenoid-derived plant hormones involved in many processes ... Cotton is one of the most important economic crops in the world,and it is a major source of fiber in the textile industry.Strigolactones(SLs)are a class of carotenoid-derived plant hormones involved in many processes of plant growth and development,although the functions of SL in fiber development remain largely unknown.Here,we found that the endogenous SLs were significantly higher in fibers at 20 days post-anthesis(DPA).Exogenous SLs significantly increased fiber length and cell wall thickness.Furthermore,we cloned three key SL biosynthetic genes,namely GhD27,GhMAX3,and GhMAX4,which were highly expressed in fibers,and subcellular localization analyses revealed that GhD27,GhMAX3,and GhMAX4 were localized in the chloroplast.The exogenous expression of GhD27,GhMAX3,and GhMAX4 complemented the physiological phenotypes of d27,max3,and max4 mutations in Arabidopsis,respectively.Knockdown of GhD27,GhMAX3,and GhMAX4 in cotton resulted in increased numbers of axillary buds and leaves,reduced fiber length,and significantly reduced fiber thickness.These findings revealed that SLs participate in plant growth,fiber elongation,and secondary cell wall formation in cotton.These results provide new and effective genetic resources for improving cotton fiber yield and plant architecture. 展开更多
关键词 STRIGOLACTONES fiber elongation secondary cell wall thickening COTTON
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Lateral root elongation in maize is related to auxin synthesis and transportation mediated by N metabolism under a mixed NO_(3)^(–) and NH_(4)^(+) supply
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作者 Peng Wang Lan Yang +4 位作者 Xichao Sun Wenjun Shi Rui Dong Yuanhua Wu Guohua Mi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期1048-1060,共13页
A mixed nitrate (NO_(3)^(–)) and ammonium (NH_(4)^(+)) supply can promote root growth in maize (Zea mays),however,the changes in root morphology and the related physiological mechanism under different N forms are sti... A mixed nitrate (NO_(3)^(–)) and ammonium (NH_(4)^(+)) supply can promote root growth in maize (Zea mays),however,the changes in root morphology and the related physiological mechanism under different N forms are still unclear.Here,maize seedlings were grown hydroponically with three N supplied in three different forms (NO_(3)^(–)only,75/25 NO_(3)^(–)/NH_(4)^(+)and NH_(4)^(+)only).Compared with sole NO_(3)^(–)or NH_(4)^(+),the mixed N supply increased the total root length of maize but did not affect the number of axial roots.The main reason was the increased total lateral root length,while the average lateral root (LR) length in each axle was only slightly increased.In addition,the average LR density of 2nd whorl crown root under mixed N was also increased.Compared with sole nitrate,mixed N could improve the N metabolism of roots (such as the N influx rate,nitrate reductase (NR) and glutamine synthase (GS)enzyme activities and total amino content of the roots).Experiments with exogenously added NR and GS inhibitors suggested that the increase in the average LR length under mixed N was related to the process of N assimilation,and whether the NR mediated NO synthesis participates in this process needs further exploration.Meanwhile,an investigation of the changes in root-shoot ratio and carbon (C) concentration showed that C transportation from shoots to roots may not be the key factor in mediating lateral root elongation,and the changes in the sugar concentration in roots further proved this conclusion.Furthermore,the synthesis and transportation of auxin in axial roots may play a key role in lateral root elongation,in which the expression of ZmPIN1B and ZmPIN9 may be involved in this pathway.This study preliminarily clarified the changes in root morphology and explored the possible physiological mechanism under a mixed N supply in maize,which may provide some theoretical basis for the cultivation of crop varieties with high N efficiency. 展开更多
关键词 MAIZE NO_(3)^(–)/NH_(4)^(+)ratio lateral root elongation N assimilation indole-3-acetic acid
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Generation and detection of pulsed terahertz waves in gas: from elongated plasmas to microplasmas
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作者 Fabrizio BUCCHERI Pingjie HUANG Xi-Cheng ZHANG 《Frontiers of Optoelectronics》 EI CSCD 2018年第3期209-244,共36页
The past two decades have seen an exponential growth of interest in one of the least explored region of the electromagnetic spectrum, the terahertz (THz) frequency band, ranging from to 0.1 to 10 THz. Once only the ... The past two decades have seen an exponential growth of interest in one of the least explored region of the electromagnetic spectrum, the terahertz (THz) frequency band, ranging from to 0.1 to 10 THz. Once only the realm of astrophysicists studying the background radiation of the universe, THz waves have become little by little relevant in the most diverse fields, such as medical imaging, industrial inspection, remote sensing, fundamental science, and so on. Remarkably, THz wave radiation can be generated and detected by using ambient air as the source and the sensor. This is accomplished by creating plasma under the illumination of intense femtosecond laser fields. The integration of such a plasma source and sensor in THz time-domain techniques allows spectral measurements covering the whole THz gap (0.1 to 10 THz), further increasing the impact of this scientific tool in the study of the four states of matter. In this review, the authors introduce a new paradigm for implementing THz plasma techniques. Specifically, we replaced the use of elongated plasmas, ranging from few mm to several cm, with sub-mm plasmas, which will be referred to as microplasmas, obtained by focusing ultrafast laser pulses with high numerical aperture optics (NA from 0.1 to 0.9). The experimental study of the THz emission and detection from laser-induced plasmas of submillimeter size are presented. Regarding the microplasma source, one of the interesting phenomena is that the main direction of THz wave emission is almost orthogonal to the laser propagation direction, unlike that of elongated plasmas. Perhaps the most important achievement is the demonstra- tion that laser pulse energies lower than 1 μJ are sufficientto generate measurable THz pulses from ambient air, thus reducing the required laser energy requirement of two orders of magnitude compared to the state of art. This significant decrease in the required laser energy will make plasma-based THz techniques more accessible to the scientific community, as well as opening new potential industrial applications. Finally, experimental observations of THz radiation detection with microplasmas are also presented. As fully coherent detection was not achieved in this work, the results presented herein are to be considered a first step to understand the peculiarities involved in using the micro- plasma as a THz sensor. 展开更多
关键词 terahertz waves Terahertz Air Photonics generation and detection elongated plasmas MICROPLASMAS
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