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世界耳鼻咽喉头颈外科杂志英文版 2024年第4期10卷 270-274页

作者： Kalantari Shirin Zadheidar Sevrin Heydarifard Zahra Nejati Ahmad Sadeghi kaveh Malekshahi Somayeh Shatizadeh Ghavami Nastaran Mokhtari-Azad Talat Shafiei-Jandaghi Nazanin-Zahra Department of Virology School of Public Health Tehran University of Medical Sciences Tehran Iran Department of Virology Faculty of Medical Sciences Tarbiat Modares University Tehran Iran

Background and Objectives: Epstein-Barr virus (EBV) infection is ubiquitous all around the world. Tonsils seem to be candidate replication sites for EBV, and these tissues can be infected acutely or chronically. Some studies reported an association between EBV infection and tonsillar hypertrophy. In this study, we aimed to evaluate the presence and copy number of the EBV genome in tonsil tissue specimens of patients with tonsillar ***: A cross-sectional study was performed on 50 fresh tonsil tissue samples from children, who underwent tonsillectomy because of tonsillar hypertrophy. Patients'' tonsil tissues were evaluated using real-time polymerase chain reaction for EBV genome and viral load. Finally, the results were analyzed using SPSS ***: EBV genome was detected in 58% (29/50) of tonsillar tissues. The relationship between EBV genome detection rate and age groups was in the statistical significance range (P = 0.051). Among 29 positive cases, the average EBV viral load was (3.1 × 105) copy/g ± (0.5 × 105) copy/g. No significant difference was observed among different sex and age groups for EBV viral ***: Herein, EBV genome detection could support the colonization of EBV in the tonsils, which may have a direct or indirect association with the pathogenesis of tonsillar hypertrophy.

关键词： EBV Iran tonsillar hypertrophy

Acquisition of Weak Signals in Multi-Constellation Frequency Domain Receivers

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Positioning 2013年第2期4卷 144-152页

作者： kaveh Mollaiyan Rock Santerre René Jr. Landry Department of Electrical Engineering école de Technologie Supérieure Montreal Canada Department of Geomatics Sciences Université Laval Quebec Canada Department of Electrical Engineering école de Technologie Supérieure Montreal Canada

New positioning applications’ availability requirements demand receivers with higher sensitivities and ability to process multiple GNSS signals. Possible applications include acquiring one signal per GNSS constellation in the same frequency band and combining them for increased sensitivity or predicting acquisition of other signals. Frequency domain processing can be used for this purpose, since it benefits from parallel processing capabilities of Fast Fourier Transform (FFT), which can be efficiently implemented in software receivers. On the other hand, long coherent integration times are mainly limited due to large FFT size in receivers using frequency domain techniques. A new method is proposed to address the problems in frequency domain receivers without compromising the resources and execution time. A pre-correlation accumulation (PCA) is proposed to partition the received samples into one-code-period blocks, and to sum them together. As a result, the noise is averaged out and the correlation results will gain more power, provided that the relative phase between the data segments is compensated for. In addition to simplicity, the proposed PCA method enables the use of one-size FFT for all integration times. A post-correlation peak combination is also proposed to remove the need for double buffering. The proposed methods are implemented in a configurable Simulink model, developed for acquiring recorded GNSS signals. For weak signal scenarios, a Spirent GPS simulator is used as a source. Acquisition results for GPS L1 C/A and GLONASS L1OF are shown and the performance of the proposed technique is discussed. The proposed techniques target GNSS receivers using frequency domain processing aiming at accommodating all the GNSS signals, while minimizing resource usage. They also apply to weak signal acquisition in frequency domain to answer the availability demand of today’s GNSS positioning applications.

关键词： FFT Acquisition Frequency Domain Receiver Weak Signal Multi-Constellation

The Effect of Alluvial Foundation on the Earth Dams Settlement

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Open Journal of Geology 2017年第3期7卷 360-373页

作者： Masoud Ghaemi kaveh Ahangari Ali Noorzad Kamran Goshtasbi Department of Mining Engineering Science and Research Branch Islamic Azad University Tehran Iran Faculty of Water and Environmental Engineering Shahid Beheshti University Tehran Iran Faculty of Mining Engineering Tarbiat Modares University Tehran Iran

Careful monitoring in the earth dams, to measure deformation caused by settlement and movement has always been a concern for engineers in the field. In order to measure settlement and deformation of earth dams, usually the precision instruments of settlement set and combined Inclinometer that is commonly referred to IS instrument, will be used. In some dams, because the thickness of alluvium is high and there is no possibility of alluvium removal (technically and economically and in terms of performance), there is no possibility to place the end of IS instrument (precision instruments of Inclinometer-settlement set) in the rock foundation. Inevitably, have to accept installing pipes in the weak and the deformable alluvial foundation that this leads to errors in the calculation of the actual settlement (absolute settlement) in different parts of the dam body. The purpose of this paper is to present new and refine criteria for predicting settlement and deformation in earth dams. The study is based on conditions in three dams with a deformation quite alluvial (Agh Chai, Narmashir and Gilan-e Gharb) to provide settlement criteria affected by alluvial foundation. To achieve this goal, the settlement of dams was simulated by using finite difference method with FLAC3D software and then the modeling results were compared with reading IS instrument. In the end, the caliber of the model and validate the results, by using regression analysis techniques and scrutinized modeling parameters with real situations and then by using MATLAB software and Curve Fitting Toolbox, a new criteria for the settlement based on elasticity modulus, cohesion, friction angle, density of earth dam and alluvial foundation was obtained. The results of these studies show that, by using the new criteria measures, the amount of settlement and deformation for the dams with alluvial foundation can be corrected after instrument readings and the error rate in reading IS instrument can be greatly reduced.

关键词： Earth Dam Alluvial Foundation Settlement Finite Difference FLAC3D MATLAB Curve Fitting Refine Criteria IS Instrument

Most Frequent Comorbidities in Patients With Lichen Planopilaris:A Cross-Sectional Study

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International Journal of Dermatology and Venereology 2023年第4期6卷 229-232页

作者： kaveh Gharaei Nejad Reyhaneh Ghadarjani Hojat Eftekhari Saba Sheykholeslami Skin Research Center Razi HospitalGuilan University of Medical SciencesRasht ***Iran Department of Pathology Razi HospitalGuilan University of Medical SciencesRasht ***Iran.

Objective:Lichen planopilaris (LPP) is a rare skin disorder,but it is also the most common cause of scarring alopecia in *** main cause of this disease is unknown,but it is considered to be related to the immune status of the *** comorbidities are reportedly associated with LPP,such as hypertension,depression,thyroiditis,diabetes,and *** the present study,we aimed to investigate the frequency of comorbidities in patients with LPP who were referred to Razi Hospital in Rasht,Iran,from 2016 to ***:This cross-sectional study involved 60 patients with cicatricial alopecia patches (scarring and irreversible) and clinical signs and symptoms consistent with active *** association between demographic data and comorbidities in patients with LPP was evaluated with the chi-square test andt ***:The results showed that the most common comorbidities were vitamin D deficiency (24.3%),hypothyroidism (17.6%),anemia (16.2%),asthma and allergy (14.8%),hypertension (13.5%),diabetes (9.5%),and vitiligo (4.5%).There was no statistically significant association of sex,age,or body mass index with LPP according to the presence or absence of underlying disease (P = 0.440,P = 0.108,andP = 0.340,respectively);however,there was a statistically significant difference in the presence of comorbidities according to age (P = 0.018).Conclusion:The results illustrated that women with vitamin D deficiency are more prone to LPP than are patients with other pre-existing underlying diseases.

关键词： comorbidities lichen planopilaris skin disorder alopecia

Solution Combustion Synthesis of Nano-Crystalline Alumina Powders

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材料科学与工程（中英文版） 2010年第8期4卷 80-84页

作者： Shirin Saket Susan Rasouli Ebrahim Ghasemi kaveh Tahmasebi Department of Metallurgy and Materials Sciences Lamic Zad University Meibod Branch Meibod 89615/275 Iran Departement of Nanomaterials ＆ Nanocoatings Institute of Color Science and Technology （ICST） Tehran *** Iran Department of Metallurgy and Materials Sciences Shiraz University Shiraz 71345 Iran

Ohio solid organ transplantation consortium criteria for liver transplantation in patients with alcoholic liver disease

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World Journal of Hepatology 2016年第27期8卷 1149-1154页

作者： kaveh Hajifathalian Annette Humberson Mohamad A Hanouneh David S Barnes Zubin Arora Nizar N Zein Bijan Eghtesad Dympna Kelly Ibrahim A Hanouneh Department of Internal Medicine Cleveland Clinic Foundation Department of Transplant Social Work Cleveland Clinic Foundation Department of Gastroenterology and Hepatology Cleveland Clinic Foundation Department of General Surgery Cleveland Clinic Foundation

AIM To evaluate risk of recidivism on a case-by-case *** From our center's liver transplant program,we selected patients with alcoholic liver disease who were listed for transplant based on Ohio Solid Organ Transplantation Consortium(OSOTC) exception *** were considered to have either a low or medium risk of recidivism,and had at least one or three or more months of abstinence,*** were matched based on gender,age,and Model for End-Stage Liver Disease(MELD) score to controls with alcohol-induced cirrhosis from Organ Procurement and Transplant Network *** Thirty six patients with alcoholic liver disease were approved for listing based on OSOTC exception criteria and were matched to 72 *** patients(53%) with a median [Inter-quartile range(IQR)] MELD score of 24(13) received transplant and were followed for a median of 3.4 *** were matched to 38 controls with a median(IQR) MELD score of 25(9).At one and five years,cumulative survival rates(± standard error) were 90% ± 7% and 92% ± 5% and 73% ± 12% and 77% ± 8% in patients and controls,respectively(Log-rank test,P = 0.837).Four(21%) patients resumed drinking by last follow-up *** Compared to traditional criteria for assessment of risk of recidivism,a careful selection process with more flexibility to evaluate eligibility on a case-by-case basis can lead to similar survival rates after transplantation.

关键词： Alcohol-induced disorders Alcoholic liver cirrhosis Mortality Survival Liver transplantation

Protective Effects of Vitamin E on Diabetes-induced Oxidative Stress Status and Homocysteine in the Rat Heart

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Journal of Pharmacy and Pharmacology 2017年第10期5卷 708-716页

作者： Mojtaba Beyramzadeh Mohammad Hassan Khadem Ansari kaveh Azimzadeh Siamak Salami Faculty of Medicine Hacettepe University Ankara 06100 Turkey Faculty of Medicine Urmia University of Medical Sciences Urmia *** Iran Veterinary Faculty Urmia Branch Islamic Azad University Urmia *** Iran Faculty of Medicine Shahid Beheshti Medical University Tehran *** Iran

Objective： We aimed to investigate protective effects ofvit E on oxidative stress status and homocysteine （Hey） in cardiac tissue of diabetic rats. Methods： Sixteen Wistar male rats were treated with STZ （streptozotocin）（60 mg/kg） to induce diabetes. Diabetic rats were divided into two groups： NTD （non-treated diabetic） and VETD （vit E-treated diabetic） rats. The VETD group received 300 mg/kg vit E with daily feeding. Eight normal rats of the same age were used as the control group. After 6 weeks, the rats were anesthetized, their cardiac tissue was removed, and homogenated supernatant was separated. Samples were assayed for TAC （total antioxidant capacity）, LPO （lipid peroxidation）, nitrite （NO2）, nitrate （NO3）, and Hcy. Key Findings： The contents of LPO, NO3 and Hcy in NTD compared to control group indicate a significant increase, but the levels of these parameters decreased in VETD （p 〈 0.05）. There was a significant decrease in the amount of TAC in the NTD group but in VETD group, that significantly increased （p 〈 0.05）. The amount of NO2 in NTD and VETD groups, compared to the control group, did not show any significant changes （p 〉 0.05）. Conclusions： Significant decrease of oxidative stress and Hey in the cardiac tissue caused by vit E supplementation strongly indicated that this radical scavenger may promote a protective effect on diabetic cardiomyopathy through the attenuation of oxidative stress and increase antioxidant defense mechanism.

关键词： Vitamin E oxidative stress homocysteine diabetic rats.

SARS-COV-2 infection(coronavirus disease 2019)for the gastrointestinal consultant

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World Journal of Gastroenterology 2020年第14期26卷 1546-1553页

作者： kaveh Hajifathalian Srihari Mahadev Robert E Schwartz Shawn Shah Kartik Sampath Felice Schnoll-Sussman Robert S Brown Jr David Carr-Locke David E Cohen Reem Z Sharaiha Division of Gastroenterology and Hepatology Weill Cornell MedicineNew York-Presbyterian HospitalNew YorkNY 10021United States

The current pandemic due to the severe acute respiratory syndrome coronavirus 2 has caused an extreme burden for health care systems globally,and the number of cases is expected to continue to increase,at least in the immediate *** virus is estimated to have infected more than 1.5 million *** available reports suggest that gastrointestinal(GI)involvement in coronavirus disease 2019(COVID-19)is common and in some cases the GI symptoms may precede the respiratory *** addition to direct effects of severe acute respiratory syndrome coronavirus 2,the infected patients remain at risk for the complications commonly managed by gastroenterology and hepatology *** most commonly reported GI manifestation of COVID-19 is diarrhea,which is reported in a third to up to more than half of the *** to moderate elevation of the liver enzymes are also common,although no case of acute liver failure has been reported so *** of the medications used for treatment of COVID-19 can also be associated with GI symptoms or liver injury and can be included in the differential diagnosis in these *** the diagnosis of the infection is currently based on RNA analysis in respiratory samples,the available literature on fecal shedding of this virus suggests that fecal RNA testing might prove to be a useful diagnostic *** is reasonable to delay all non-urgent endoscopic procedures during the peak of the pandemic and use additional protective equipment such as N95 respirators during endoscopy while most patients can be considered high risk for having been exposed to the virus.

关键词： SARS-CoV-2 COVID-19 Gastroenterology Hepatology Liver

MR Visualization of Spinal Dural Arterio-Venous Fistula Using T2-Weighted 3D SPACE—A Spin-Echo Technique

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Journal of Biomedical Science and Engineering 2015年第5期8卷 327-332页

作者： Franz A. Fellner Christine M. Fellner Rene Chapot kaveh Akbari Institute of Radiology Kepler University Clinic Medical Faculty of the Johannes Kepler University Linz Austria Institute ofNeuroradiology Alfried-Krupp-Krankenhaus Essen Germany

Spinal dural arteriovenous fistulas (SDAVF) account for about 70% of all spinal AV shunts. We re-port on a 56-year-old male patient with progressive neurological symptoms. Pre- and post-contrast MR imaging of the spine, including contrast-enhanced MR angiography was done on a 1.5 T MR scanner. In addition a special (pre-contrast) 3D turbo-spin-echo sequence with variable flip angle evolution (SPACE) was performed providing a slice thickness of 0.9 mm. T2-weighted images showed extensive widened and tortuous vascular structures with typical flow voids intradurally due to dilated pial veins. The origin of the spinal dural arteriovenous fistula was found to be the radiculomeningeal artery at level D10/11 on the left side, visualized by the T2-weighted 3D SPACE sequence and CE MRA. After imaging the patient was referred to an interventional neuroradiology department for therapy. With the detailed information from MR imaging concerning the fistula level the interventional radiologist was able to find the fistula immediately and consequently treated it successfully by endovascular therapy. Interpreting the MR images of this obvious case of a SDAVF, SPACE sequence after post processing with 3D MPR software directly led to the location of the AV shunt at D10/11 on the left side, better than 3D contrast-enhanced MR angiography did. Therefore, SPACE can be a useful adjunct in further evaluation of spinal dural arteriovenous fistula and especially in defining fistula level.

关键词： Contrast Enhanced Magnetic Resonance Angiography (CE MRA) 3D Pulse Sequences 3D SPACE Spinal Dural Arterio-Venous Fistula (SDAVF)

Impact of severe plastic deformation on kinetics and thermodynamics of hydrogen storage in magnesium and its alloys

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Journal of Materials Science & Technology 2023年第15期146卷 221-239页

作者： kaveh Edalati Etsuo Akiba Walter J.Botta Yuri Estrin Ricardo Floriano Daniel Fruchart Thierry Grosdidier Zenji Horita Jacques Huot Hai-Wen Li Huai-Jun Lin Ádám Révész Michael J.Zehetbauer WPI International Institute for Carbon-Neutral Energy Research(WPI-I2CNER)Kyushu UniversityFukuokaJapan International Research Center for Hydrogen Energy Kyushu UniversityFukuokaJapan Departamento de Engenharia de Materiais Universidade Federal de São CarlosSao Carlos-SPBrazil Department of Materials Science and Engineering Monash UniversityClaytonVIC 3800Australia Department of Mechanical Engineering the University of Western AustraliaCrawleyWA 6009Australia School of Applied Sciences University of Campinas(UNICAMP)LimeiraSão PauloBrazil Institut Néel CNRS&UGA38042 GrenobleFrance JOMI-LEMAN SA 74890 FessyFrance Universitéde Lorraine Laboratory of Excellence on Design of Alloy Metals for low-mass Structures(DAMAS)MetzF-57070France Universitéde Lorraine Laboratoire d’Etude des Microstructures et de Mécanique des Matériaux(LEM3 UMR 7239)MetzF-57070France Graduate School of Engineering Kyushu Institute of TechnologyKitakyushuJapan Magnesium Research Center Kumamoto UniversityKumamotoJapan Synchrotron Light Application Center Saga UniversitySagaJapan Hydrogen Research Institute Universitédu QuébecàTrois-Rivières3351 des ForgesTrois-RivièresQC G9A 5H7Canada Hefei General Machinery Research Institute Hefei 230031China Institute of Advanced Wear&Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou 510632China Department of Materials Physics Eötvös UniversityBudapestH-1518P.O.B.32BudapestHungary Faculty of Physics University of ViennaBoltzmanngasse 5A-1090 WienAustria

Magnesium and its alloys are the most investigated materials for solid-state hydrogen storage in the form of metal hydrides,but there are still unresolved problems with the kinetics and thermodynamics of hydrogenation and dehydrogenation of this group of *** plastic deformation(SPD)methods,such as equal-channel angular pressing(ECAP),high-pressure torsion(HPT),intensive rolling,and fast forging,have been widely used to enhance the activation,air resistance,and hydrogenation/dehydrogenation kinetics of Mg-based hydrogen storage materials by introducing ultrafine/nanoscale grains and crystal lattice *** severely deformed materials,particularly in the presence of alloying additives or second-phase nanoparticles,can show not only fast hydrogen absorption/desorption kinetics but also good cycling *** was shown that some materials that are apparently inert to hydrogen can absorb hydrogen after SPD ***,the SPD methods were effectively used for hydrogen binding-energy engineering and synthesizing new magnesium alloys with low thermodynamic stability for reversible low/room-temperature hydrogen storage,such as nanoglasses,high-entropy alloys,and metastable phases including the high-pressureγ-MgH2 *** work reviews recent advances in the development of Mg-based hydrogen storage materials by SPD processing and discusses their potential in future applications.

关键词： Severe plastic deformation(SPD) Nanostructured materials Ultrafine-grained(UFG)materials Magnesium hydride(MgH_(2)) Magnesium-based alloys Hydrogen absorption Hydrogenation kinetics Hydrogen storage thermodynamics