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World Journal of Pediatric Surgery 2022年第2期5卷 29-33页

作者： mohammad ashkan moslehi Pediatric Interventional Pulmonology Division Medical SchoolShiraz University of Medical SciencesShirazIran

Background Several children are affected by airway foreign body aspiration(FBA)resulting from life-threatening *** has been considered the major symptom and is defined as airway blockage by a foreign body(FB),leading to marked morbidity or *** retrospective study indicates the possibility of misdiagnosis or rigid bronchoscope(RB)failure,which is the standard gold method for extracting FB in the *** Six children with airway FBA who failed treatment using RB between 2018 and 2019 were retrospectively *** inclusion criterion was a history of failure to extract FB using RB followed by flexible fiberoptic bronchoscopy(FFB).Results In the present study,among 63 patients who had undergone rigid bronchoscopy,airway FBs were successfully removed in 57(90.48%).Rigid bronchoscopy failed in 6(9.52%)*** age of cases at the time of bronchoscopy ranged from 11 months to 13 *** was performed to extract missing or remaining FBs and was done successfully in all *** patients made an uneventful recovery following FB extraction using the FFB *** It is not easy to diagnose and treat airway FB in *** bronchoscopy has been approved as a method to manage airway FB,but a negative bronchoscopy result must usually be interpreted *** is applicable as a proper and relatively safe diagnostic and therapeutic tool in managing airway FBs among the pediatric population,especially in cases where rigid bronchoscopy was performed but missed or failed to extract the FB.

关键词： airway rigid removed

Experimental investigation into effects of the natural polymer and nanoclay particles on the EOR performance of chemical flooding in carbonate reservoirs

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Petroleum Science 2024年第2期21卷 951-961页

作者： Amir mohammad Zamani ashkan Moslemi Kamran Hassani Department of Petroleum Engineering Islamic Azad University Science and Research BranchTehranIran Institute of Petroleum Engineering University of TehranTehranIran

This paper aims to investigate the tragacanth gum potential as a natural polymer combined with natural clay mineral(montmorillonite,kaolinite,and illite)nanoparticles(NPs)to form NP-polymer suspension for enhanced oil recovery(EOR)in carbonate *** gravimetric analysis(TGA)tests were conducted initially in order to evaluate the properties of tragacanth ***,scanning electron microscopy(SEM)and energy-dispersive X-ray(EDX)tests were used to detect the structure of clay *** various scenarios,the effects of natural NPs and polymer on the wettability alteration,interfacial tension(IFT)reduction,viscosity improvement,and oil recovery were investigated through contact angle system,ring method,Anton Paar viscometer,and core flooding tests,*** entire experiment was conducted at 25,50,and 75℃,*** to the experimental results,the clay minerals alone did not have a significant effect on viscosity,but the addition of minerals to the polymer solution leads to the viscosity enhancement remarkably,resulting mobility ratio *** clay NPs,the combination of natural polymer and kaolinite results in increased viscosity at all *** wettability alteration was also observed in the case of natural polymer and illite *** in combination with natural polymer showed an ability in reducing ***,the results of displacement experiments revealed that the combination of natural polymer and kaolinite could be the best option for EOR due to its substantial ability to improve the recovery factor.

关键词： Chemical flooding Tragacanth gum Clay nanoparticle Wettability IFT

A Chebyshev/Legendre polynomial interpolation approach for fingerprint orientation estimation smoothing and prediction

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第12期11卷 976-988页

作者： ashkan TASHK mohammad Sadegh HELFROUSH mohammad Javad DEHGHANI Faculty of Electrical Engineering Shiraz University of Technology Shiraz Iran

We introduce a novel coarse ridge orientation smoothing algorithm based on orthogonal polynomials, which can be used to estimate the orientation field (OF) for fingerprint areas of no ridge information. This method does not need any base information of singular points (SPs). The algorithm uses a consecutive application of filtering-and model-based orientation smoothing methods. A Gaussian filter has been employed for the former. The latter conditionally employs one of the orthogonal polynomials such as Legendre and Chebyshev type I or II, based on the results obtained at the filtering-based stage. To evaluate our proposed method, a variety of exclusive fingerprint classification and minutiae-based matching experiments have been conducted on the fingerprint images of FVC2000 DB2, FVC2004 DB3 and DB4 databases. Results showed that our proposed method has achieved higher SP detection, classification, and verification performance as compared to competing methods.

关键词： Coherence Consistency Fingerprint orientation Legendre/Chebyshev orthogonal polynomials

Risk factors for congenital nasolacrimal duct obstruction in children under two years of age

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国际眼科杂志 2025年第1期25卷 17-23页

作者： Rozhin Kasiri Gholamreza Khataminia Ali Kasiri mohammad Sadegh Mirdehghan mohammad Armin Kasiri Infectious Ophthalmologic Research Center Ahvaz Jundishapur University of Medical SciencesAhvaz ***Iran Islamic Azad University Tehran Medical Sciences Tehran ***Iran

·AIM:To identify various risk factors that may play a significant role in the development of congenital nasolacrimal duct obstruction(CNLDO).·METHODS:This observational case-control study included a case group of 122 children less than two years of age with CNLDO who underwent probing and irrigation treatment at the ophthalmology department of Imam Khomeini Hospital in Ahvaz,Iran,from June 2022 to June2024.A control group of 122 age-matched children without CNLDO was also included for *** was collected from the children's medical records.·RESULTS:The study found a significant correlation between the occurrence of CNLDO and several maternal factors,such as preeclampsia,the use of levothyroxine,hypothyroidism,having more than three pregnancies(gravidity>3),natural pregnancy,and gestational diabetes ***,in children,factors,such as oxygen therapy,anemia,reflux,jaundice,and a family history of CNLDO in first-degree relatives were associated with CNLDO,and maternal preeclampsia and hypothyroidism were found to significantly increase the risk of developing CNLDO in children.·CONCLUSION:Given that CNLDO affects both premature and full-term children,the present findings may potentially facilitate the early identification of children and infants at risk of nasolacrimal duct obstruction,thereby preventing the onset of chronic dacryocystitis.

关键词： risk factors congenital nasolacrimal duct obstruction children

The journey of multifunctional bone scaffolds fabricated from traditional toward modern techniques

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Bio-Design and Manufacturing 2020年第4期3卷 281-306页

作者： ashkan Bigham Firoozeh Foroughi Erfan Rezvani Ghomi mohammad Rafienia Rasoul Esmaeely Neisiany Seeram Ramakrishna Department of Biomaterials Tissue Engineering and NanotechnologySchool of Advanced Technologies in Medicine(ATiM)Isfahan University of Medical SciencesIsfahanIran Department of Materials Science and Engineering Faculty of EngineeringNational University of Singapore9 Engineering Drive 1Singapore 117576Singapore Department of Mechanical Engineering Center for Nanofibers and NanotechnologyNational University of SingaporeSingapore 119260Singapore Biosensor Research Center Isfahan University of Medical SciencesIsfahanIran Department of Materials and Polymer Engineering Faculty of EngineeringHakim Sabzevari University*** SabzevarIran

As a bone scaffold,meeting all basic requirements besides dealing with other bone-related issues-bone cancer and accelerated regeneration-is not expected from traditional scaffolds,but a newer class of scaffolds called *** a clinical point of view,being a multifunctional scaffold means reducing in healing time,direct costs-medicine,surgery,and hospitalization-and indirect costs-loss of mobility,losing job,and *** main aim of the present review is following the multifunctional bone scaffolds trend to deal with both bone regeneration and cancer *** consideration is given to different fabrication techniques which have been applied to yield these materials spanning from traditional to modern ***,the hierarchical structure of bone plus bone cancers and available medicines to them are introduced to familiarize the potential reader of review with the pluri-disciplinary essence of the ***,a brief discussion relating to the future trend of these materials is provided.

关键词： Multifunctional scaffolds Bone cancer Fabrication techniques Bone tissue regeneration

Numerical study of camber and stagger angle effects on the aerodynamic performance of tandem-blade cascades

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Propulsion and Power Research 2018年第1期7卷 30-42页

作者： Behshad Ghazanfari Mahdi Nili-Ahmadabadi ashkan Torabi-Farsani mohammad Hossein Noorsalehi Department of Mechanical Engineering Isfahan University of TechnologyIsfahan ***Iran

Jet engine manufacturers and designers are seeking for lighter and smaller type of axial *** the aerodynamic characteristics of blades is carried out by controlling the boundary *** way to control the boundary layer is using tandem ***-blade cascades are capable of using highly loaded stages for axial compressors because they provide more works than single-blade *** other words,tandem blades help to achieve a specified total pressure ratio with less number of ***,one of the most important problems for researchers is to optimize the aerodynamic parameters of tandem *** the geometrical parameters of blades is a method to achieve this *** this work,the stagger and camber angle of each blade are first changed while the other geometrical parameters such as overall camber,total stagger angle,the axial overlap,percent pitch and chord ratio are ***,the overall camber angle of tandem blade is changed by increasing the difference between the stagger angle of the first and second blade while the type of two airfoils,axial overlap and percent pitch,overall chord length and overall stagger angle are *** aerodynamic performances of the generated tandem-blade cascades are obtained using two-dimensional numerical solution of *** this,a viscous turbulent flow solver is used for solving the Navier-Stokes *** these simulations,inlet Mach number is fixed to 0.6.

关键词： Tandem blade Axial compressors Cascade Camber angle Stagger angle Flow deflection Loss coefficient

The combined effect of ultrasound treatment and leek (Allium ampeloprasum) extract on the quality properties of beef

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Food Bioscience 2022年第3期47卷 1060-1069页

作者： Ali Mehrabani ashkan Jebelli Javan mohammad Ali Hesarinejad Ali Mahdavi Mahnoosh Parsaeimehr Department of Food Hygiene Faculty of Veterinary MedicineSemnan UniversitySemnanIran Department of Food Processing Research Institute of Food Science and Technology (RIFST)MashhadIran

One of the most important physicochemical properties of meat is its *** impact of Leek (Allium ampeloprasum ) extract and ultrasound on meat quality and molecular weight distribution of Longissimus lumborum muscles was *** have been treated with ultrasound (100 and 300 W during 10,20,and 30 min) and Leek-derived exogenous proteases (16.9 and 33.8U/g) simultaneously and *** combined effect of enzyme and ultrasound in 10 and 20 min increased the pH *** was also increased the proteolytic activity of *** meat quality,the filtering residues,cooking loss,shear force,and hardness were reduced;water-binding capacity,emulsion capacity,and emulsion stability were *** electrophoretic pattern of myofibrillar proteins showed the muscle fibers were severely degraded in the combined *** can be concluded that this process could be used as an alternative to the chemical tenderizing agents in the meat industry.

关键词： Leek extract Proteolytic activity Quality properties Tenderization Ultrasound-assisted enzyme treatment

Static and Dynamic Pull-In Instability of Nano-Beams Resting on Elastic Foundation Based on the Nonlocal Elasticity Theory

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Chinese Journal of Mechanical Engineering 2017年第2期30卷 385-397页

作者： HAMID M Sedighi ashkan Sheikhanzadeh Mechanical Engineering Department Faculty of EngineeringShahid Chamran University of Ahvaz Departmentof Mechanical Engineering Najafabad BranchIslamic Azad Univesity

This paper provides the static and dynamic pullin behavior of nano-beams resting on the elastic foundation based on the nonlocal theory which is able to capture the size effects for structures in micron and sub-micron scales. For this purpose, the governing equation of motion and the boundary conditions are driven using a variational approach. This formulation includes the influences of fringing field and intermolecular forces such as Casimir and van der Waals forces. The differential quadrature （DQ） method is employed as a high-order approximation to discretize the governing nonlinear differential equation, yielding more accurate results with a Considerably smaller number of grid points. In addition, a powerful analytical method called parameter expansion method （PEM） is utilized to compute the dynamic solution and frequency-amplitude relationship. It is illustrated that the first two terms in series expansions are sufficient to produce an acceptable solution of the mentioned structure. Finally, the effects of basic parameters on static and dynamic pull-in insta- bility and natural frequency are studied.

关键词： Static and dynamic pull·in voltages Size dependent Nonlocal theory Euler·Bernoulli beam model Differential quadrature method Parameter Expansion method

Full-Quantum Simulation of Graphene Self-Switching Diodes

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Chinese Physics Letters 2019年第6期36卷 53-56页

作者： ashkan Horri Rahim Faez Department of Electrical Engineering Arak Branch Islamic Azad University Arak Department of Electrical Engineering Tehran Sharif University of Technology

We present a quantum study on the electrical behavior of the self-switching diode(SSD). Our simulation is based on non-equilibrium Green's function formalism along with an atomistic tight-binding model. Using this method,electrical characteristics of devices, such as turn-on voltage, rectification ratio, and differential resistance, are investigated. Also, the effects of geometrical variations on the electrical parameters of SSDs are simulated. The carrier distribution inside the nano-channel is successfully simulated in a two-dimensional model under zero,reverse, and forward bias conditions. The results indicate that the turn-on voltage, rectification ratio, and differential resistance can be optimized by choosing appropriate geometrical parameters.

关键词： Full-Quantum Simulation Graphene Self-Switching Diodes

Effect of alumina and silica nanocomposite based on polyacrylamide on light and heavy oil recovery in presence of formation water using micromodel

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Petroleum 2024年第2期10卷 338-353页

作者： ashkan Maleki Behnam Sedaee Alireza Bahramian Sajjad Gharechelou Nahid Sarlak Arash Mehdizad mohammad reza Rasaei Aliakbar Dehghan Science and Research Branch Islamic Azad UniversityIran Institute of Petroleum Engineering School of Chemical EngineeringUniversity of TehranIran School of Geology College of ScienceUniversity of TehranIran Department of Chemistry Lorestan University Iran Iranian Offshore Oil Company Iran

Increasing world request for energy has made oil extraction from reservoirs more *** novel EOR methods have been proposed and utilized for this *** nanocomposites in chemical flooding is one of these novel *** this study,we investigated the impact of six injection solutions on the recovery of light and heavy oil with the presence of two different brines as formation water using a homogenous glass *** of the injection solutions were based on a 40,000 ppm Na Cl synthetic seawater(SSW),one of which was additive free and the others were prepared by dispersing nanocomposite silica-based polyacrylamide(NCSP),nanocomposite alumina-based polyacrylamide(NCAP),the combination of both nanocomposites silica and alumina based on polyacrylamide(NCSAP),surfactant(CTAB)and polyacrylamide(PAM)with a concentration of 1000 ppm as *** Stability of nanocomposites was tested against the salinity of the brine and temperature using salinity and DSC tests which were *** stability tests,IFT,contact angle and oil recovery measurements were *** results revealed that in addition to the effect of silica and alumina nanocomposite in reducing interfacial tension and wettability alteration,control of mobility ratio caused a major improvement in sweeping efficiency and oil *** to the sweeping behavior of injected fluids,it was found that the main effect of surfactant was wettability alteration,for polyacrylamide was mobility control and for nanocomposites was the reduction of interfacial tension between oil and injected fluid,which was completely analyzed and checked ***,NCSAP with 95.83%and 70.33%and CTAB with 84.35%and 91%have the highest light oil recoveries at 250,000 ppm and 180,000 ppm salinity,respectively which is related to the superposition effect of interactions between nanocomposites,solution and *** on our results it can be concluded that the most effective mechanism in oil recovery was I

关键词： Enhanced oil recovery Micromodel Polyacrylamide Nanocomposite Salinity Alumina and silica nanoparticles