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How crystal configuration affects the position detection accuracy in pixelated molecular SPECT imaging systems?

Nuclear Science and Techniques 2017年第4期28卷 24-30页

作者： Hojjat Mahani Gholamreza Raisali alireza kamali-asl Mohammad Reza Ay Radiation Application Research School Nuclear Science and Technology Research Institute Tehran Iran Research Center for Molecular and Cellular Imaging Tehran University of Medical Science Tehran Iran Radiation Medicine Department Shahid Beheshti UniversityTehran Iran Department of Medical Physics and Biomedical Engineering Tehran University of Medical Science Tehran Iran

It is well known that inter-crystal scattering and penetration(ICS-P) are major spatial resolution limiting parameters in dedicated SPECT scanners with pixelated *** this study,the effect of ICS-P on crystal identification in different crystal configurations was evaluated using GATE Monte Carlo simulation.A ^(99m)Tc pencil-beam toward central crystal element was *** incident angle was assumed to vary from 0° to 45° in 5° *** effects of various crystal configurations such as pixel-size,pixel-gap,and crystal material were *** influence of photon energy on the crystal identification(CI) was also *** detection accuracy(PDA) was defined as a factor indicating performance of the ***,a set of ^(99m)Tc point-source simulations was performed in order to calculate peak-to-valley(PVR) ratio for each *** results show that the CsI(Na)manifests higher PDA than NaI(TI) and YAP(Ce).In addition,as the incident angle increases,the crystal becomes less accurate in positioning of the *** a crystal-dependent critical angle,the PDA monotonically *** PDA reaches 0.44 for the CsI(Na) at 45° beam *** PDAs obtained by the point-source evaluation also behave the same as for the pencil-beam *** addition,the PVRs derived from flood images linearly correlate their corresponding *** conclusion,quantitative assessment of ICS-P is mandatory for scanner design and modeling the system matrix during iterative reconstruction algorithms for the purpose of resolution modeling in ultra-high-resolution SPECT.

关键词： Monte Carlo GATE Molecular SPECT Position detection accuracy Pixelated crystal

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Semi-automated carotid lumen segmentation in computed tomography angiography images

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The Journal of Biomedical Research 2017年第6期31卷 548-558页

作者： Hamid Reza Hemmati Mahdi Alizadeh alireza kamali-asl Shapour Shirani Radiation Medicine Engineering Department Shahid Beheshti UniversityTehran ***Iran Department of Neurosurgery Thomas Jefferson University HospitalPhiladelphiaPAl9107USA Department of Radiology Thomas Jefferson University HospitalPhiladelphiaPA 19107USA Department of Imaging Tehran University of Medical ScienceTehran ***Iran

Carotid artery stenosis causes narrowing of carotid lumens and may lead to brain infarction. The purpose of this study was to develop a semi-automated method of segmenting vessel walls, surrounding tissues, and more importantly, the carotid artery lumen by contrast computed tomography angiography（CTA） images and to define the severity of stenosis and present a three-dimensional model of the carotid for visual inspection. In vivo contrast CTA images of 14 patients（7 normal subjects and 7 patients undergoing endarterectomy） were analyzed using a multi-step segmentation algorithm. This method uses graph cut followed by watershed and Hessian based shortest path method in order to extract lumen boundary correctly without being corrupted in the presence of surrounding *** measurements of the proposed method were compared with those of manual delineation by independent board-certified radiologists. The results were quantitatively evaluated using spatial overlap surface distance indices. A slightly strong match was shown in terms of dice similarity coefficient（DSC） = 0.87±0.08; mean surface distance（Dmsd）= 0.32±0.32; root mean squared surface distance（Drmssd） = 0.49±0.54 and maximum surface distance（Dmax）=2.14±2.08 between manual and automated segmentation of common, internal and external carotid arteries, carotid bifurcation and stenotic artery, respectively. Quantitative measurements showed that the proposed method has high potential to segment the carotid lumen and is robust to the changes of the lumen diameter and the shape of the stenosis area at the bifurcation site. The proposed method for CTA images provides a fast and reliable tool to quantify the severity of carotid artery stenosis.

关键词： computed tomography angiography carotid atherosclerosis centerline extraction segmentation

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Detection of small bowel tumor in wireless capsule endoscopy images using an adaptive neuro-fuzzy inference system

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The Journal of Biomedical Research 2017年第5期31卷 419-427页

作者： Mahdi Alizadeh Omid Haji Maghsoudi Kaveh Sharzehi Hamid Reza Hemati alireza kamali asl alireza Talebpour Department of Bioengineering Temple University Philadelphia PAl9121 USA Department of Medicine Section of Gastroenterology School of Medicine Temple University Philadelphia PA 19140. USA Department of Radiation Medicine Engineering ShahidBeheshti University Tehran *** Iran. Department of Electrical and Computer Engineering ShahidBeheshti University Tehran *** Iran.

Automatic diagnosis tool helps physicians to evaluate capsule endoscopic examinations faster and more *** purpose of this study was to evaluate the validity and reliability of an automatic post-processing method for identifying and classifying wireless capsule endoscopic images, and investigate statistical measures to differentiate normal and abnormal images. The proposed technique consists of two main stages, namely, feature extraction and classification. Primarily, 32 features incorporating four statistical measures(contrast, correlation, homogeneity and energy) calculated from co-occurrence metrics were computed. Then, mutual information was used to select features with maximal dependence on the target class and with minimal redundancy between features. Finally, a trained classifier, adaptive neuro-fuzzy interface system was implemented to classify endoscopic images into tumor, healthy and unhealthy classes. Classification accuracy of 94.2% was obtained using the proposed pipeline. Such techniques are valuable for accurate detection characterization and interpretation of endoscopic images.

关键词： adaptive neuro-fuzzy inference system co-occurrence matrix wireless capsule endoscopy texture feature

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Effects of Magnetic Particles Entrance Arrangements on Mixing Efficiency of a Magnetic Bead Micromixer

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Nano-Micro Letters 2014年第1期6卷 30-37页

作者： Reza kamali Seyed alireza Shekoohi alireza Binesh School of Mechanical Engineering Shiraz University

In this study, a computer code is developed to numerically investigate a magnetic bead micromixer under different conditions. The micromixer consists of a microchannel and numerous micro magnetic particles which enter the micromixer by fluid flows and are actuated by an alternating magnetic field normal to the main flow. An important feature of micromixer which is not considered before by researchers is the particle entrance arrangement into the micromixer. This parameter could effectively affect the micromixer efficiency. There are two general micro magnetic particle entrance arrangements in magnetic bead micromixers: determined position entrance and random position entrance. In the case of determined position entrances, micro magnetic particles enter the micromixer at specific positions of entrance cross section. However, in a random position entrance,particles enter the microchannel with no order. In this study mixing efficiencies of identical magnetic bead micromixers which only differ in particle entrance arrangement are numerically investigated and *** results reported in this paper illustrate that the prepared computer code can be one of the most powerful and beneficial tools for the magnetic bead micromixer performance analysis. In addition, the results show that some features of the magnetic bead micromixer are strongly affected by the entrance arrangement of the particles.

关键词： Magnetic bead micromixer Mixing efficiency Particle entrance arrangement

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Operation and Flexibility Contribution of Natural Gas Tanks in Multi-carrier Energy Systems

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CSEE Journal of Power and Energy Systems 2021年第3期7卷 622-631页

作者： alireza Hamedi Ali Reza Seifi Dariush Keihan asl School of Electrical and Computer Engineering Shiraz UniversityShirazIran

Energy storage systems(ESSs)have an assistive role in the operation of multi-carrier energy *** paper presents a type of natural gas(NG)ESS called NG tank and studies the operation and flexibility contributions of this ESS in the *** tank modeling and formulation are unified the same as the electrical *** NG tank and the electrical ESS models are implemented on a large-scale multi-carrier energy network and the impressive effects of utilizing these units are investigated in the operational planning of the energy *** optimal operational problem is solved utilizing the teaching learning based optimization(TLBO)algorithm to minimize the operational cost of the system.

关键词： Electrical ESS multi-carrier energy system NG tank optimal operation

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Design, synthesis, and nanoengineered modification of spherical graphene surface by layered double hydroxide (LDH) for removal of As (Ⅲ) from aqueous solutions

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Chinese Journal of Chemical Engineering 2023年第1期53卷 374-380页

作者： Najma kamali Jahan B.Ghasemi Ghodsi Mohammadi Ziarani Sahar Moradian alireza Badiei School of Chemistry College of ScienceUniversity of TehranTehranIran Department of Organic Chemistry Faculty of ChemistryAlzahra UniversityVanak SquareTehranIran

In this study, new nano spherical graphene modified with LDH(Layered Double Hydroxide) was prepared and used to remove As(Ⅲ) ion from aqueous solutions. At first, graphene oxide was synthesized from graphite using a well-known Hammer method. The obtained graphene oxide solution was sprayed in octanol solution under different temperatures and sprayed speed as influenced variables. The structure and physical characterization of synthesized spherical graphene oxide were determined by various techniques,including FT-IR, N_(2) adsorption–desorption, SEM, TEM, and EDX. In the next step, the hydrothermal method was applied to deposition LDH on the spherical graphene oxide. The synthesized spherical graphene modified by LDH was used to remove As(Ⅲ) as a toxic heavy metal ion. The effect of influenced variables including p H, contact time, amount of sorbent, and type eluent studied and the optimum values were as 8, 30, 50, and HCl(0.5 mol·L^(-1)), respectively. After optimization, the studied sorbent was shown a high adsorption capacity(149.3 mg·g^(-1)). The adsorption mechanism and kinetic models exhibited good agreement with the Langmuir isotherm and pseudo-second-order trends, respectively. Besides, the synthesized product was tested for seven times without significant loss in its sorption efficiency.

关键词： Graphene-based spherical adsorbent Layered double hydroxide(LDH) Adsorption Spray-assisted deep-frying

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Ectoparasites of lesser mouse eared bat,Myotis blythii from Kermanshah Iran

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Asian Pacific Journal of Tropical Medicine 2010年第5期3卷 371-373页

作者： Vatandoost Hassan Telmadarraiy Zakkyeh Sharifi Mozafar Moradi alireza kamali Maryam Taran Mojtaba School of Public Health Tehran University of Medical SciencesP.O.Box:6446-14155TehranIran Biology Department Environment Research CenterKermanshah University of RaziKermanshahIran

Objective:To identify the ectoparasits of lesser mouse eared bat,Myotis blythii inside the MahiDasth cave in Kermanshah province,***:A total of 30 lasser mouse eared bat(Myotis blythii) in a cave close to Kermanshah city were hunted with special net and were transported to the *** anesthetizing by chloroform,ectoparasites from these bats were removed and ***:The ectoparasites include flies,ticks and *** 39 identified flies belonged to two families including Strebilidae(7.7%) and Nyctmbiidae(92.3%).A total number of 5 ticks of larval,nymphal and adult stages of Ixodes vespertilionis and 18 mites from Spiturnicidae family were ***:The result of this study is a clue for the identification of ectoparasites from bats and implication of possible prevention measures for diseases transmitted by ectoparasites.

关键词： Myotis blythii Bat flies ectoparasites Iran

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Experimental investigation into L-Arg and L-Cys eco-friendly surfactants in enhanced oil recovery by considering IFT reduction and wettability alteration

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Petroleum Science 2020年第1期17卷 105-117页

作者： Hamed Foroughi asl Ghasem Zargar Abbas Khaksar Manshad Mohammad Ali Takassi Jagar A.Ali alireza Keshavarz Department of Petroleum Engineering Abadan Faculty of Petroleum EngineeringPetroleum University of Technology(PUT)AbadanIran Department of Petroleum Engineering Ahwaz Faculty of Petroleum EngineeringPetroleum University of Technology(PUT)AhwazIran Department of Petroleum Engineering Faculty of EngineeringSoran UniversitySoranKurdistan RegionIraq Department of Petroleum Engineering College of EngineeringKnowledge UniversityErbilKurdistan RegionIraq School of Engineering Edith Cowan UniversityJoondalupWA 6027Australia

Surfactant flooding is an important technique used to improve oil recovery from mature oil reservoirs due to minimizing the interfacial tension(IFT)between oil and water and/or altering the rock wettability toward water-wet using various surfactant agents including cationic,anionic,non-ionic,and amphoteric *** this study,two amino-acid based surfactants,named lauroyl arginine(L-Arg)and lauroyl cysteine(L-Cys),were synthesized and used to reduce the IFT of oil–water systems and alter the wettability of carbonate rocks,thus improving oil recovery from oil-wet carbonate *** synthesized surfactants were characterized using Fourier transform infrared spectroscopy and nuclear magnetic resonance analyses,and the critical micelle concentration(CMC)of surfactant solutions was determined using conductivity,pH,and turbidity *** results showed that the CMCs of L-Arg and L-Cys solutions were 2000 and 4500 ppm,*** was found that using L-Arg and L-Cys solutions at their CMCs,the IFT and contact angle were reduced from 34.5 to 18.0 and15.4 mN/m,and from 144°to 78°and 75°,***,the L-Arg and L-Cys solutions enabled approximately 11.9%and 8.9%additional recovery of OOIP(original oil in place).It was identified that both amino-acid surfactants can be used to improve oil recovery due to their desirable effects on the EOR mechanisms at their CMC ranges.

关键词： Chemical EOR Amino-acid surfactant IFT Wettability Coreflooding

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Synthesis of Quinoxalinophenazine Derivatives and Reaction of 3,12-Dimethylbenzo[a]quinoxalino-[2,3-c]phenazine with Mercury(Ⅱ) Bromide: Spectral and Structural Characterization

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Chinese Journal of Structural Chemistry 2014年第10期33卷 1460-1466页

作者： Ahmad Poursattar Marjani Bayram Parsa Habashi Hojjatollah Rahchamani Jabbar Khalafy alireza Dadrass Hooman Yaghoobnejad asl Department of Chemistry Faculty of Science Urmia University Department of Chemistry Missouri University of Science and TechnologyRolla MO 65409 USA

A new series of quinoxalinophenazine derivatives were synthesized in good yields by the reaction of 2,3-dibromonaphthalene-1,4-dione with different aryl-1,2-diamines in DMF as solvent at 120-130℃ or under reflux conditions. 3,12-dimethylbenzo[a]quinoxalino[2,3-c] phenazine with bidentate character reacts with mercury（II） bromide to give suitable crystals. All products were confirmed by IR, ^1H and ^13C NMR, and the metal complex by single-crystal X-ray method. The crystal（C24H16Br2HgN4, Mr = 720.82） belongs to the triclinic system, space group P1 with a = 10.186（6）, b = 10.421（6）, c = 11.470（7） A, α = 98.670（7）, β = 95.069（7）, γ = 109.831（7）°, V = 1119.4（12） A3, Z = 2, Dc = 2.139 Mg/m^3, μ = 10.46 mm^-1, F（000） = 676, R = 0.043 and wR = 0.115 for 3982 observed reflections with I 〉 2σ（I）.

关键词： aryl-1 2-diamines 2 3-dibromonaphthalene-1 4-dione mercury complexes quinoxalinophenazine derivatives N N-chelating

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Cochlear Synaptopathy Following Noise Exposure in Guinea Pigs: Its Electrophysiological and Histological Assessments

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Sound & Vibration 2020年第3期54卷 163-177页

作者： Parvane Mahdi Akram Pourbakht Vahid Pirhajati Mahabadi alireza Karimi Yazdi Mahtab Rabbani Anari Mohammad kamali Rehabilitation Research Center Department of AudiologySchool of Rehabilitation SciencesIran University of Medical SciencesTehran15459-13487Iran Department of Neurosciences School of MedicineIran University of Medical SciencesTehran14496-14535Iran Department of Otorhinolaryngology Tehran University of Medical SciencesTehran14197-33141Iran Department of Rehabilitation Management Iran University of Medical SciencesTehran15459-13487Iran

Exposure to high level of noise,may cause the permanent cochlear synaptic *** present study,a model of noise induced cochlear synaptopathy was established and the electrophysiological and histological metrics for its assessment was designed.6 guinea pigs were subjected to a synaptopathic noise(octave band of 4 kHz at 104 dB SPL,for 2-h).The amplitude growth curve of Auditory Brainstem Response(ABR)wave-I and wave-III latency shift in presence of noise were *** indexes were considered in pre-exposure,1 day post exposure(1DPE),1 week post exposure(1WPE)and 1 month post exposure(1MPE)to ***,the samples were histologically *** wave-I amplitude was different between pre and 1DPE(p-value≤0.05).However,at 1WPE,it was recovered at low intensities but at 70 dB SPL and above,the differences persisted even till *** masked ABR,the latency shift of wave-III was different between pre and 3 post exposure assessments(p-value≤0.05).Electro-microscopic analysis confirmed the synaptic degeneration,as the ribbons were larger than normal,hollow inside,and spherical and irregular in shape,also,the post synaptic density was abnormally thick and missed its flat *** data revealed that noise at level below that can produce permanent hearing loss,can incur synaptic ***,noise is considered to be more damaging than previously ***,designing tools for clinical assessment of synaptopathy is beneficial in comprehensive auditory evaluation of those with history of noise exposure and also in hearing protection planning.

关键词： Cochlear synaptopathy noise induced hearing loss hidden hearing loss excitotoxicity hearing protection

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