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Sensing the heavy water concentration in an H_(2)O-D_(2)O mixture by solid-solid phononic crystals

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Chinese Physics B 2024年第4期33卷 493-498页

作者： Mohammadreza Rahimi Ali bahrami Optoelectronic and Nanophotonics Research Laboratory(ONRL) Faculty of Electrical EngineeringSahand University of TechnologyTabrizIran

A new method based on phononic crystals is presented to detect the concentration of heavy water(D_(2)O)in an H_(2)O-D_(2)O *** have been obtained and analyzed in the concentration range of 0%-10%and 90%-100%D_(2)O.A proposed structure of tungsten scatterers in an aluminum host is *** order to detect the target material,a cavity region is considered as a sound wave resonator in which the target material with different concentrations of D_(2)O is *** changing the concentration of D_(2)O in the H_(2)O-D_(2)O mixture,the resonance frequency undergoes a frequency *** 1%change in D_(2)O concentration in the H_(2)O-D_(2)O mixture causes a frequency change of about 120 *** finite element method is used as the numerical method to calculate and analyze the natural frequencies and transmission spectra of the proposed *** performance evaluation index shows a high Q factor up to 1475758 and a high sensitivity up to 13075,which are acceptable values for sensing *** other figures of merit related to the detection performance also indicate high-quality performance of the designed sensor.

关键词： phononic crystals sensor H_(2)O-D_(2)O mixture cavity

Stratigraphy of the Alveolina elliptica group from the Middle Eocene of Iran:Calibration with calcareous nannofossils biozones and description of Alveolina ozcani n. sp.

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Journal of Palaeogeography 2024年第1期13卷 54-79页

作者： Mehdi Hadi Lorenzo Consorti Ali bahrami Mohammad Parandavar Saeed Khorramdel Department of Geology Faculty of SciencesUniversity of IsfahanIsfahanIran Institute of Marine Sciences(ISMAR-CNR) Area Science ParkBasovizza34149 TriesteItaly National Iranian Oil Company Exploration DirectorateSheikh Bahaei SquareTehranIran Department of Geology Faculty of ScienceFerdowsi University of MashhadMashhadIran

Precise taxonomy and the chronostratigraphic calibration of the Middle Eocene Alveolina from Central Iran is here undertaken from the Chah-Talkh section of the southern Sabzevar region(Central Iran). We have identified Alveolina kieli, Alveolina stercusmuris and Alveolina nuttalli along with the new species Alveolina ozcani n. sp. that we include into the Alveolina elliptica group. We have also found Nummulites uroniensis, Nummulites obesus and Nummulites cf. verneuili and associated calcareous nannofossils that look reliable to make thoughtful correlations with the Shallow Benthic Zones(SBZ). The foraminiferal biostratigraphy suggests an assignment to the upper part of the lower Lutetian-lower part of the middle Lutetian,SBZ13(Middle Eocene), further strengthened through the identification of the calcareous nannofossil NP14b-NP15b or CNE8-CNE10 biozones, providing a solid correlation with the global stratigraphic standards.

关键词： Alveolina Calcareous nannofossil Central neo-tethys Central Iran Middle Eocene Biostratigraphy

Cancer cell cycle heterogeneity as a critical determinant of therapeutic resistance

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Genes & Diseases 2024年第1期11卷 189-204页

作者： Ebrahim H.Maleki Ahmad Reza bahrami Maryam M.Matin Department of Biology Faculty of ScienceFerdowsi University of Mashhad*** MashhadIran Jagiellonian Centre for Experimental Therapeutics(JCET) Jagiellonian University31-007 KrakowPoland Doctoral School of Exact and Natural Sciences Jagiellonian University30-348 KrakowPoland Industrial Biotechnology Research Group Institute of BiotechnologyFerdowsi University of Mashhad*** MashhadIran Novel Diagnostics and Therapeutics Research Group Institute of BiotechnologyFerdowsi University of Mashhad***MashhadIran Stem Cell and Regenerative Medicine Research Group Iranian Academic Center for EducationCulture and Research(ACECR)Khorasan Razavi Branch917751376 MashhadIran

Intra-tumor heterogeneity is now arguably one of the most-studied topics in tumor biology,as it represents a major obstacle to effective cancer *** tumor cells are highly diverse at genetic,epigenetic,and phenotypic levels,intra-tumor heterogeneity can be assumed as an important contributing factor to the nullification of chemotherapeutic effects,and recurrence of the *** on the role of heterogeneous subpopulations of cancer cells with varying cell-cycle dynamics and behavior during cancer progression and treatment;herein,we aim to establish a comprehensive definition for adaptation of neoplastic cells against *** discuss two parallel and yet distinct subpopulations of tumor cells that play pivotal roles in reducing the effects of chemotherapy:"resistant"and"tolerant"***,this review also highlights the impact of the quiescent phase of the cell cycle as a survival mechanism for cancer *** understanding the mechanisms under-lying the quiescence,it provides an insightful perspective on cancer stem cells(CsCs)and their dual and intertwined functions based on their cell cycle state in response to ***-over,CSCs,epithelial-mesenchymal transformed cells,circulating tumor cells(CTCs),and disseminated tumor cells(DTCs),which are mostly in a quiescent state of the cell cycle are proved to have multiple biological links and can be implicated in our viewpoint of cell cycle heterogeneity in ***,increasing our knowledge of cell cycle heterogeneity is a key to identifying new therapeutic solutions,and this emerging concept may provide us with new opportunities to prevent the dreadful cancer recurrence.

关键词： Cancer stem cells(CSCs) Carcinoma Cell cycle heterogeneity Quiescence Therapy resistance Therapy tolerance Tumor dormancy

Proposed numerical and machine learning models for fiber-reinforced polymer concrete-steel hollow and solid elliptical columns

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1169-1194页

作者： Tang QIONG Ishan JHA Alireza bahrami Haytham F.ISLEEM Rakesh KUMAR Pijush SAMUI School of Applied Technologies Qujing Normal UniversityQujing 655011China Department of Civil Engineering Indian Institute of Technology-BHUVaranasi 221005India Department of Building Engineering Energy Systems and Sustainability ScienceFaculty of Engineering and Sustainable DevelopmentUniversity of GävleGävle 80176Sweden Department of Civil Engineering National Institute of Technology-PatnaPatna 800005India

This study employs a hybrid approach,integrating finite element method(FEM)simulations with machine learning(ML)techniques to investigate the structural performance of double-skin tubular columns(DSTCs)reinforced with glass fiber-reinforced polymer(GFRP).The investigation involves a comprehensive examination of critical parameters,including aspect ratio,concrete strength,number of GFRP confinement layers,and dimensions of steel tubes used in DSTCs,through comparative analyses and parametric *** ensure the credibility of the findings,the results are rigorously validated against experimental data,establishing the precision and trustworthiness of the *** present research work examines the use of the columns with elliptical cross-sections and contributes valuable insights into the application of FEM and ML in the design and evaluation of structural systems within the field of structural engineering.

关键词： elliptical column fiber-reinforced polymer machine learning finite element method ABAQUS

Role of molecular imaging in prognosis,diagnosis,and treatment of gastrointestinal cancers:An update on new therapeutic methods

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World Journal of Methodology 2024年第4期14卷 43-60页

作者： Mobina Fathi Hayder Jasim Taher Sabah Jassim Al-Rubiae Shirin Yaghoobpoor Ashkan bahrami Reza Eshraghi Hossein Sadri Mahsa Asadi Anar Ali Gholamrezanezhad Student Research Committee School of MedicineShahid Beheshti University of Medical SciencesTehran ***Iran Department of Radiology Hilla University CollegeBabylon 00964Iraq Faculty of Medicine Kashan University of Medical SciencesKashan ***Iran Department of Radiology Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90033United States

One of the leading causes of cancer-related death is gastrointestinal cancer,which has a significant morbidity and mortality *** preoperative risk assessment is essential for directing patient care,its biological behavior cannot be accurately predicted by conventional imaging *** pathophysiological information in anatomical imaging that cannot be visually identified can now be converted into high-dimensional quantitative image features thanks to the developing discipline of molecular *** order to enable molecular tissue profile in vivo,molecular imaging has most recently been utilized to phenotype the expression of single receptors and targets of biological *** is expected that molecular imaging will become increasingly important in the near future,driven by the expanding range of biological therapies for *** this live molecular fingerprinting,molecular imaging can be utilized to drive expression-tailored customized *** technical aspects of molecular imaging are first briefly discussed in this review,followed by an examination of the most recent research on the diagnosis,prognosis,and potential future clinical methods of molecular imaging for GI tract malignancies.

关键词： Molecular imaging Personalized medicine Gastrointestinal cancers Positron emission tomography-computed tomography

Numerical investigation of flow and heat transfer behind a two-dimensional backward-facing step equipped with a semi-porous baffle

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Journal of Central South University 2021年第11期28卷 3354-3367页

作者： Hamid-Reza bahrami Department of Mechanical Engineering Qom University of TechnologyQom 37195Iran

The backward-facing step is a critical problem existing in many engineering and industrial *** this study,a semi-porous baffle(the root of the baffle is a porous medium and the tip is solid) is placed behind the *** effects of the length of the porous part,and the baffle location on the energy transfer and pressure drop are studied in different Reynolds numbers(Re=100,200,300,400,500).The effect of the Darcy number of the porous medium on the aforementioned parameters is also *** the local maximum and average relative Nusselt numbers(divided by the Nusselt of the base case with no baffle at the same Reynolds) and relative pressure drop(calculated as the relative Nusselt number) are *** results show that by adoption of the proper length of the porous medium,the average relative and maximum local Nusselt numbers could be enhanced by 20% and 90%,*** permeable porous media give better energy *** example,porous media with Da=10^(-5) give 30% better maximum local Nusselt number and about 7% higher average Nusselt number with respect to the same case with Da=10^(-2).

关键词： porous media enhanced heat transfer baffle backward-facing step two-dimensional channel

Nonalcoholic fatty liver disease in developing countries

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World Journal of Gastroenterology 2005年第24期11卷 3808-3809页

作者： Hossein bahrami Department of Epidemiology

TO THE EDITORNonalcoholic fatty liver disease (NAFLD) is an increasingly known medical entity with high prevalence, about 1 0 to 24 percent in general population and up to 74% in obese population[1]. The prevalence of the disease is expected to increase worldwide, as we are encountering the global obesity epidemic and the trend in developing countries toward the Western lifestyles. However, it looks that there are some differences between the demographic and epidemiologic features of NAFLD in developing and developed countries.

关键词： Nonalcoholic fatty liver Developing countries

Kinetic grain growth, shape memory and corrosion behavior of two Cu-based shape memory alloys after thermomechanical treatment

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Transactions of Nonferrous Metals Society of China 2013年第10期23卷 2896-2904页

作者： Ahmad Ostovari MOGHADDAM Mostafa KETABCHI Reza bahrami Department of Mining and Metallurgical Engineering Amirkabir University of Technology

Metallurgical and mechanical properties along with shape memory and corrosion behavior of Cu-11.8% AI-3.7% Ni-1 %Mn and Cu-11% A1 5.6% Mn shape memory alloys （SMAs） were comparatively studied. The influence of grain refinement on the properties was studied by optical microscopy （OM）, scanning electron microscopy （SEM）, differential scanning calorimetry （DSC）, potentiodynamic polarizations and bend and tensile tests. Static recrystallization and kinetic grain growth show a rapid recrystallization in the first 15 s of annealing at 800℃ followed by grain growths. The minimum grain sizes obtained after 15 s are 90 and 260 μm for Cu-A1-Ni-Mn and Cu-A1-Mn, respectively. Tensile tests show typical three-stage curves for both alloys, and it is seen that alloys exhibit high fracture stress and strain after grain refinement. Microstructural observations show zig-zag morphology of β 1martensite in the Cu-A1-Ni-Mn and coexistence of β1 and y1 in the Cu-A1-Mn, which were confirmed by differential scanning calorimetry results. The shape memory ratios （17） of the alloys before thermomechanieal treatment, and after thermomechanical annealing at 800 ℃ for different time up to 15 min followed by water quenching, were evaluated. In addition, corrosion behavior of alloys after grain refinement was analyzed by means of potentiodynamic polarization measurements. The results showed that the anodic reactions were dominated by dissolution of copper, and Cu-AI-Ni-Mn alloy exhibits a better corrosion resistance than Cu-A1-Mn alloy.

关键词： shape memory alloys (SMAs) grain refinement corrosion shape memory properties

Modified-DBR-based semi-omnidirectional multilayer anti-reflection coating for tandem solar cells

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Chinese Physics B 2014年第2期23卷 609-613页

作者： Ali bahrami Shahram Mohammadnejad Nima Jouyandeh Abkenar Nanoptronics Research Center Department of Electrical and Electronics EngineeringIran University of Science and Technology

In this paper, multilayer antireflection coatings are designed by modifying the thickness of two and three paired layer distributed Bragg reflector （DBR） structure. Our proposed DBR-based structures show antireflection behaviors, in spite of the reflection treatment in traditional DBR structures. Firstly, the proposed structures are designed to be equivalent to the theoretical ideal triple-layer （TL） antireflection coating （ARC）. Therefore, the problem of finding a suitable material for the middle layer of triple structure is solved. Simulation results show the significant equivalency for the reflectance of proposed structures to the ideal TL ARC at the same wavelengths and incident angles. Also, the design of the structure is changed in order to present the constant reflectance coefficient over a wide range of wavelengths. This structure enhances the omni-directionality of the multilayer ARC.

关键词： antireflection coating distributed bragg reflector solar cell