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Dynamic Stability of Passive Bipedal Walking on Rough Terrain： A Preliminary Simulation Study

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Journal of Bionic Engineering 2012年第4期9卷 423-433页

作者： Parsa nassiri Afshar Lei Ren School of Mechanical Aerospace and Civil Engineering University of Manchester Manchester M13 9PL UK Key Laboratory of Bionic Engineering (Ministry of Education China) Jilin University Changehun 130022 P.R. China

A simplified 2D passive dynamic model was simulated to walk down on a rough slope surface defined by deterministic profiles to investigate how the walking stability changes with increasing surface roughness. Our results show that the passive walker can walk on rough surfaces subject to surface roughness up to approximately 0.1% of its leg length. This indicates that bipedal walkers based on passive dynamics may possess some intrinsic stability to adapt to rough terrains although the maxi- mum roughness they can tolerate is small. Orbital stability method was used to quantify the walking stability before the walker started to fall over, It was found that the average maximum Floquet multiplier increases with surface roughness in a non-linear form. Although the passive walker remained orbitally stable for all the simulation cases, the results suggest that the possibility of the bipedal model moving away from its limit cycle increases with the surface roughness if subjected to additional perturbations. The number of consecutive steps before falling was used to measure the walking stability after the passive walker started to fall over. The results show that the number of steps before falling decreases exponentially with the increase in surface roughness. When the roughness magnitude approached to 0.73% of the walker＇s leg length, it fell down to the ground as soon as it entered into the uneven terrain. It was also found that shifting the phase angle of the surface profile has apparent affect on the system stability. This is probably because point contact was used to simulate the heel strikes and the resulted variations in system states at heel strikes may have pronounced impact on the passive gaits, which have narrow basins of attraction. These results would provide insight into how the dynamic stability of passive bipedal walkers evolves with increasing surface roughness.

关键词： bipedal walking rough terrain dynamic stability human locomotion

Instanton Induced Charged Fermion and Neutrino Masses in a U（3）c × U（3）L × V（3）a Gauge Symmetry

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Chinese Physics Letters 2014年第6期31卷 52-54页

作者： S. nassiri Laboratory of High Energy Physics Modeling and Simulation Faculty of Science Rabat Morocco

Using instanton effects, we consider a U（3）c × U（3）L × U（3）R gauge symmetry obtained from intersecting D6-ranes. This is equivalent to the trinification model extended by the three U（1） factors that survive as globM symmetries in the low energy effective model. In the corresponding three-stack, the fermion masses are induced by the possible stringy corrections to the corresponding superpotential by using E2-instantons. Using the known data with neutrino masses mvr-1 eV, we show the magnitudes of the relevant scales.

关键词： Gages

Effect of periocular injection of celecoxib and propranolol on ocular level of vascular endothelial growth factor in a diabetic mouse model

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International Journal of Ophthalmology(English edition) 2016年第6期9卷 821-824页

作者： Samar nassiri Gholamreza Houshmand Mostafa Feghhi Alireza Kheirollah Mohammad Bahadoram Nariman nassiri Department of Ophthalmology Infectious Ophthalmic Research CenterSchool of MedicineAhvaz Jundishapur University of Medical SciencesAhvaz 61357-15794KhuzestanIran Department of Pharmacology School of PharmacyAhvaz Jundishapour University of Medical SciencesAhvaz 61357-15794KhuzestanIran Department of Biochemistry Cellular&Molecular Research CenterAhvaz Jundishapur University of Medical SciencesAhvaz 61357-15794KhuzestanIran Medical Student Research Committee and Social Determinant of Health Research Center Ahvaz Jundishapur University of Medical SciencesAhvaz 61357-15794KhuzestanIran Jules Stein Eye Institute David Geffen School of MedicineUniversity of California at Los AngelesLos Angeles 90095CaliforniaUSA

AIM： To investigate the effects of periocular injection of propranolol and celecoxib on ocular levels of vascular endothelial growth factor （VEGF） in a diabetic mouse model. METHODS： Forty 4-6wk BALB-C male mice weighing 20-25 g were used. The study groups included： nondiabetic control （group 1）, diabetic control （group 2）, diabetic propranolol （group 3）, and diabetic celecoxib （group 4）. After induction of type 1 diabetes by streptozotocin, propranolol （10 μg） and celecoxib （200 μg dissolved in carboxymethylcellulose 0.5%） were injected periocularly. The ocular level of VEGF was measured in all the study groups using enzyme-linked immuno sorbent assay （ELISA） method. RESULTS： Ocular VEGF level was significantly increased （1.25 fold） in the diabetic control group when compared to the non-diabetic group one week after induction with streptozotocin （P=0.002）. Both periocular propranolol and celecoxib significantly reduced ocular VEGF levels （P=0.047 and P〈0.001, respectively）. The effect was more pronounced with celecoxib, CONCLUSION： The periocular administration of propranolol and celecoxib can significantly reduce ocular VEGF levels in a diabetic mouse model.

关键词： diabetic retinopathy celecoxib propranolol vascular endothelial growth factor neovascularization diabetic mouse model

Design and study of a high-current 5-cell superconducting rf cavity

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Chinese Physics C 2010年第5期34卷 603-605页

作者：刘振超 A. nassiri G. Waldschmidt School of Physics Peking University Advanced Photon Source Argonne National Laboratory9700 S Cass Ave.ArgonneIL 60439 USA

The Advanced Photon Source （APS） at Argonne National Laboratory is considering the development of a superconducting linac-based fourth-generation hard X-ray source to meet future scientific needs of the hard X-ray user community. This work specifically focuses on the design of an optimized 5-cell superconducting radio-frequency structure well suited for a high-energy, high-beam-current energy recovery linac. The cavity design parameters are based on the APS storage ring nominal 7 GeV and 100 mA beam operation. A high-current 5-cell cw superconducting cavity operating at 1.4 GHz has been designed. In order to achieve a high current, the accelerating cavity shape has been optimized and large end-cell beam pipes have been adopted. The beam break-up threshold of the cavity has been estimated using the code TDBBU, which predicts a high threshold beam current for a 7 GeV energy recovery linac model. A copper prototype cavity has been fabricated that uses half-cell modules, initially assembled by clamping the cells together.

关键词： high current superconducting cavity higher order modes

Fuzzy logic classification of mature tomatoes based on physical properties fusion

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Information Processing in Agriculture 2022年第4期9卷 547-555页

作者： Seyed Mehdi nassiri Amir Tahavoor Abdolabbas Jafari Department of Biosystems Engineering Shiraz UniversityShiraz 71441Iran Lincoln Agritech Ltd. Lincoln UniversityLincoln 7616New Zealand

Grading of fruits and vegetables is an initial step after *** is also an essential operation before *** the present study,different fuzzy algorithms for classifica-tion of mature tomato were applied and evaluated based on combinations of fruit color,size and *** membership functions of hardness were established by subject-ing samples to Instron compression test as well as the rates of *** sample was also used for image processing to determine the color and size of fruit using Matlab image processing *** and size fuzzy membership functions were established by pub-lished *** fuzzy If-Then rules were applied to classify the samples within five group outputs viz.“grade I”,“grade II”,“grade I-far market”,“processing”,and“storage”.Eighty-one fuzzy rules were reduced to 25 rules by combining the compatible *** fuzzy algorithms with different fuzzifiers(zmf,sigmf,gbellmf)and defuzzifiers(bisector,mom,and centroid)were applied,and the outputs were compared to the panelists’classi-fications in cross *** to the classification results,fuzzy algorithms grouped the fruits into correct classes with 90.9%,92.3%,88.7%,87.4%,92.4%and 93.3%accuracy for 6 models,*** best result was observed with zmf and sigmf,and gbellmf as fuzzifier and mom as defuzzifier with 93.3%***,the results revealed that the fusion of aforementioned tomato properties based on fuzzy membership functions could accurately classify the tomatoes in correct groups for different markets.

关键词： Fuzzy logic Grading Hardness Tomato Sorting

Efficacy of topical chamomile on the incidence of phlebitis due to an amiodarone infusion in coronary care patients:a double-blind,randomized controlled trial

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Journal of Integrative Medicine 2017年第5期15卷 373-378页

作者： Maryam Sharifi-Ardani Leili Yekefallah Saeed Asefzadeh Marjan nassiri-Asl School of Nursing and Midwifery Qazvin University of Medical SciencesQazvin 341197-5981Iran Social Determinants of Health Research Center Qazvin University of Medical SciencesQazvin 341197-5981Iran Cellular and Molecular Research Center Department of PharmacologyQazvin University of Medical SciencesQazvin 341197-5981Iran

BACKGROUND：Amiodarone is a useful antiarrhythmic ***,caused by intravenous amiodarone,is common in patients in coronary care units（CCUs）.OBJECTIVE：The aim of this study was to evaluate the effect of topical chamomile on the incidence of phlebitis due to the administration of an amiodarone infusion into the peripheral ***,SETTING,PARTICIPANTS AND INTERVENTIONS：This was a randomized,double-blind clinical trial,conducted on 40 patients（n=20 per group）in two groups—an intervention group（chamomile ointment）and a control group（lanoline,as a placebo）,hospitalized in the CCUs and undergoing an amiodarone infusion into the peripheral vein over 24 *** the cannulation and commencement of the infusion,placebo or chamomile ointment was rubbed in,up to 10 cm superior to the catheter and repeated every eight hours for three *** cannula site was then assessed based on the phlebitis *** OUTCOME MEASURES：The incidence and time of occurrence of phlebitis,relative risk,severity of phlebitis were the main outcome ***：Nineteen patients（19/20）in the control group had phlebitis on the first day of the study and one patient（20/20）on the second *** the intervention group,phlebitis occurred in 13 cases（13/20）on the first day and another two（2/7）was found on the second *** incidence of phlebitis was significantly different between two groups（P=0.023）.The cumulative incidence of phlebitis in the intervention group（15/20）is significantly later and lower than that in the control group（20/20）during two days（P=0.008）.Two patients in the intervention group did not develop phlebitis at all during the 3-day ***,the relative risk of phlebitis in the two groups was 0.68（P=0.008 5）.A significant difference was not observed with regard to phlebitis severity in both ***：It seems that phlebitis occurred to a lesser extent and at a later time frame in the intervention group compared to control *** chamomile may be e

关键词： phlebitis amiodarone prevention chamomile clinical trial plants, medicinal

The design of a five-cell high-current superconducting cavity

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Chinese Physics C 2012年第1期36卷 74-79页

作者：李永明朱凤全胜文 Ali nassiri 刘克新 State Key Laboratory of Nuclear Physics and Technology Institute of Heavy Ion PhysicsPeking University Advanced Photon Source Argonne National Laboratory

Energy recovery linacs are promising for achieving high average current with superior beam *** key component for accelerating such high-current beams is the superconducting radio-frequency *** design of a 1.3 GHz five-cell high-current superconducting cavity has been carried out under cooperation between Peking University and the Argonne National *** radio-frequency properties,damping of the higher order modes,multipacting and mechanical features of this cavity have been discussed and the final design is presented.

关键词： high current superconducting cavity higher order modes

Potential therapeutic applications for Terminalia chebula in Iranian traditional medicine

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Journal of Traditional Chinese Medicine 2016年第2期36卷 250-254页

作者： Assie Jokar Fatemeh Masoomi Omid Sadeghpour Mohsen nassiri-Toosi Shokouhsadat Hamedi Iranian Traditional Medicine Faculty Tehran University of Medical SciencesTehran ***Iran Department of Iranian Traditional Medicine Mazandaran University of Medical SciencesSari ***Iran Department of Traditional Pharmacy Traditional Medicine FacultyTehran University of Medical SciencesTehran ***Iran Herbal and Traditional Medicine Department Research Institute for Islamic and Complementary MedicineIran University of Medical SciencesTehran ***Iran Department of Internal Medicine Tehran University of Medical SciencesTehran ***Iran Department of Persian Pharmacy School of Persian and Complementary MedicineMashhad University of Medical SciencesMashhad ***Iran

Terminalia chebula(family:Combretaceae)is widely used in the traditional medicine of India and Iran to treat diseases that include dementia,constipation,and *** tree is known in Iranian traditional medicine(ITM)as halileh or halilaj and the fruit is used to develop *** is described in ITM as an astringent that has a"cold"and"dry"*** to the medicinal properties of Terminalia chebula were collected from important ITM sources and from modern medical databases(Pub Med,Scirus,Science Direct,and Scopus).The medicinal properties described for thistree in ITM were compared with those reported in studies of modern *** results confirm that the tree referred to as halileh in traditional books is the Terminalia chebula used in present-day *** that have not been evaluated in modern phytotherapy but have been traditionally treated with Terminalia chebula include fever,and psychological and psychiatric *** article confirms the medicinal uses of Terminalia chebula.

关键词： Fructus chebula Phytochemicals Phar macology Iranian traditional medicine

Pancreatic neuroendocrine tumor in a child of 3.5 years old

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World Journal of Pediatrics 2015年第4期11卷 386-388页

作者： Shirin Sayyahfar Seyed Javad nassiri Mitra Mehrazma Mahnaz Sadeghian Department of Pediatrics Iran University of Medical SciencesAli Asghar Children HospitalVahid Dastgerdi StreetShariati StreetTehranIran Pediatric Surgery Iran University of Medical SciencesAli Asghar Children HospitalVahid Dastgerdi StreetShariati StreetTehranIran Pathology Iran University of Medical SciencesAli Asghar Children HospitalVahid Dastgerdi StreetShariati StreetTehranIran

Background:Pancreatic neuroendocrine tumor is rarely seen,particularly in *** of the symptoms of this tumor is jaundice that may be misdiagnosed as the sign of hepatitis A,especially in countries with a high prevalence of this infectious ***:We present a 3.5-year-old girl with four weeks of icterus,who was misdiagnosed with hepatitis ***:The patient wasfi nally diagnosed as having a low grade pancreatic neuroendocrine ***:Pediatricians should be aware of or consider a tumor in differential diagnosis of jaundice,especially prolonged one in children.

关键词： hepatitis A icterus neuroendocrine tumor pancreatic tumor