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Stable Fano-like plasmonic resonance: its impact on the reversal of far-and near-field optical binding force

Communications in Theoretical Physics 2020年第4期72卷 89-105页

作者： Hamim Mahmud Rivy M R C Mahdy Nabila Masud ziaur rahman jony Saikat Chandra Das Department of Electrical&Computer Engineering North South UniversityBashundharaDhaka1229Bangladesh School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang Ave639798 Singapore Pi Labs Bangladesh LTD ARA Bhaban39Kazi Nazrul Islam AvenueKawran BazarDhaka 1215Bangladesh

Even for a 100 nm interparticle distance or a small change in particle shape,optical Fano-like plasmonic resonance mode usually vanishes *** would be remarkable if stable Fano-like resonance could somehow be achieved in distinctly shaped nanoparticles for more than 1μm interparticle distance,which corresponds to the far electromagnetic field *** such far-field Fano-like plasmonic resonance can be achieved,controlling the reversal of the far-field binding force can be attained,like the currently reported reversals for near-field *** this work,we have proposed an optical set-up to achieve such a robust and stable Fano-like plasmonic resonance,and comparatively studied its remarkable impact on controlling the reversal of near-and far-field optical binding *** our proposed set-up,the distinctly shaped plasmonic tetramers are half immersed(***-benzene)in an inhomogeneous dielectric interface and illuminated by?circular?polarized *** have demonstrated significant differences between near-and far-field optical binding forces along with the Lorentz force field,which partially depends on the object’s shape.A clear connection is shown between the far-field binding force and the resonant modes,along with a generic mechanism to achieve controllable Fano-like plasmonic resonance and the reversal of the optical binding force in both far-and near-field configurations.

关键词： Fano resonance optical binding force Lorentz force plasmonic tetramer

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Dielectric or plasmonic Mie object at air–liquid interface: The transferred and the traveling momenta of photon

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Chinese Physics B 2020年第1期29卷 311-323页

作者： M R C Mahdy Hamim Mahmud Rivy ziaur rahman jony Nabila Binte Alam Nabila Masud Golam Dastegir Al Quaderi Ibraheem Muhammad Moosa Chowdhury Mofizur rahman M Sohel rahman Department of Electrical&Computer Engineering North South UniversityBashundharaDhaka 1229Bangladesh Pi Labs Bangladesh LTD ARA Bhaban39Kazi Nazrul Islam AvenueKawran BazarDhaka 1215Bangladesh Department of Computer Science&Engineering Military Institute of Science and TechnologyDhakaBangladesh Department of Physics University of DhakaDhakaBangladesh Department of Computer Science&Engineering Bangladesh University of Engineering and Technology ECE BuildingWest PalasiDhaka-1205 Department of Computer Science&Engineering United International UniversityDhakaBangladesh

Considering the inhomogeneous or heterogeneous background, we have demonstrated that if the background and the half-immersed object are both non-absorbing, the transferred photon momentum to the pulled object can be considered as the one of Minkowski exactly at the interface. In contrast, the presence of loss inside matter, either in the half-immersed object or in the background, causes optical pushing of the object. Our analysis suggests that for half-immersed plasmonic or lossy dielectric, the transferred momentum of photon can mathematically be modeled as the type of Minkowski and also of Abraham. However, according to a final critical analysis, the idea of Abraham momentum transfer has been rejected. Hence,an obvious question arises: whence the Abraham momentum? It is demonstrated that though the transferred momentum to a half-immersed Mie object(lossy or lossless) can better be considered as the Minkowski momentum, Lorentz force analysis suggests that the momentum of a photon traveling through the continuous background, however, can be modeled as the type of Abraham. Finally, as an interesting sidewalk, a machine learning based system has been developed to predict the time-averaged force within a very short time avoiding time-consuming full wave simulation.

关键词： Abraham–Minkowski controversy dielectric interface machine learning optical force laws optical pulling force optical tractor beams

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In Vitro Antioxidant and Radio Protective Activities of Lycopene from Tomato Extract against Radiation—Induced DNA Aberration

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Journal of Biosciences and Medicines 2024年第2期12卷 202-213页

作者： Safaiatul Islam Abu Hena Mostofa Kamal Md. ziaur rahman Protul Kumar Roy A.Y.K. Md. Masud Rana Molecular Radiobiology and Biodosimetry Division Institute of Food and Radiation Biology Bangladesh Atomic Energy Commission Savar Bangladesh

Background: The accumulation of free radicals is linked to a number of diseases. Free radicals can be scavenged by antioxidants and reduce their harmful effects. It is therefore essential to look for naturally occurring antioxidants that come from plants, as synthetic antioxidants are toxic, carcinogenic and problematic for the environment. Lycopene is one of the carotenoids, a pigment that dissolves in fat and has antioxidant properties. Materials and Methods: The antioxidant and free radical scavenging activity were assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The impact of lycopene on bacteria (E. coli) susceptibility to γ-radiation was examined by radio sensitivity assay. The study also examined the induction of strand breaks in plasmid pUC19 DNA and how lycopene extract protected the DNA from γ-radiation in vitro. Results: At varying concentrations, lycopene demonstrated its ability to scavenge free radicals such as 2, 2-diphenyl-1-picrylhydrazyl (DPPH). IC50 for lycopene was determined at 112 μg/mL which was almost partial to IC50 of standard antioxidant L-ascorbic acid. The D10 value 180 Gy of E. coli was found to be >2-fold higher in the extract-containing lycopene sample than in the extract-free controls. The lycopene extracts inhibited the radiation-induced deterioration of the plasmid pUC19 DNA. At an IC50 concentration, lycopene provided the highest level of protection. Conclusion: Lycopene functions as an efficient free radical scavenger and possible natural antioxidant source. For cancer patients and others who frequently expose themselves to radiation, lycopene may be a useful plant-based pharmaceutical product for treating a variety of diseases caused by free radicals.

关键词： Radio Protective Antioxidants Free Radical DNA Damage pUC19 Plasmid Gamma Irradiation DPPH

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Absorbed dose estimations of ^(131)I for critical organs using the GEANT4 Monte Carlo simulation code

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Chinese Physics C 2012年第11期36卷 1150-1156页

作者： ziaur rahman Shakeel ur Rehman Waheed Arshed Nasir M Mirza Abdul Rashid Jahan Zeb Health Physics Division Pakistan Institute of Nuclear Science & TechnologyNiloreIslamabad 45650Pakistan Department of Physics & Applied Mathematics Pakistan Institute of Engineering & Applied SciencesNiloreIslamabad 45650Pakistan

The aim of this study is to compare the absorbed doses of critical organs of 131I using the MIRD （Medical Internal Radiation Dose） with the corresponding predictions made by GEANT4 simulations. S- values （mean absorbed dose rate per unit activity） and energy deposition per decay for critical organs of 131I for various ages, using standard cylindrical phantom comprising water and ICRP soft-tissue material, have also been estimated. In this study the effect of volume reduction of thyroid, during radiation therapy, on the calculation of absorbed dose is also being estimated using GEANT4. Photon specific energy deposition in the other organs of the neck, due to 131I decay in the thyroid organ, has also been estimated. The maximum relative difference of MIRD with the GEANT4 simulated results is 5.64% for an adult＇s critical organs of 131I. Excellent agreement was found between the results of water and ICRP soft tissue using the cylindrical model. S-values are tabulated for critical organs of 131I, using 1, 5, 10, 15 and 18 years （adults） individuals. S-values for a cylindrical thyroid of different sizes, having 3.07% relative differences of GEANT4 with Siegel ＆ Stabin results. Comparison of the experimentally measured values at 0.5 and 1 m away from neck of the ionization chamber with GEANT4 based Monte Carlo simulations results show good agreement. This study shows that GEANT4 code is an important tool for the internal dosimetry calculations.

关键词： mean absorbed dose rate GEANT4 Monte Carlo simulation and 131I critical organs

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A Progressive Approach to Generic Object Detection: A Two-Stage Framework for Image Recognition

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Computers, Materials & Continua 2023年第6期75卷 6351-6373页

作者： Muhammad Aamir ziaur rahman Waheed Ahmed Abro Uzair Aslam Bhatti Zaheer Ahmed Dayo Muhammad Ishfaq College of Computer Science Huanggang Normal UniversityHuanggangHubei438000China FAST School of Computing National University of Computer&Emerging Science(NUCES)Karachi CampusKarachi75030Pakistan School of Information and Communication Engineering Hainan UniversityHaikou68000China

Object detection in images has been identified as a critical area of research in computer vision image *** has developed several novel methods for determining an object’s location and category from an ***,there is still room for improvement in terms of detection *** study aims to develop a technique for detecting objects in *** enhance overall detection performance,we considered object detection a two-fold problem,including localization and *** proposed method generates class-independent,high-quality,and precise proposals using an agglomerative clustering *** then combine these proposals with the relevant input image to train our network on convolutional ***,a network refinement module decreases the quantity of generated proposals to produce fewer high-quality candidate ***,revised candidate proposals are sent into the network’s detection process to determine the object *** algorithm’s performance is evaluated using publicly available the PASCAL Visual Object Classes Challenge 2007(VOC2007),VOC2012,and Microsoft Common Objects in Context(MS-COCO)*** only 100 proposals per image at intersection over union((IoU)=0.5 and 0.7),the proposed method attains Detection Recall(DR)rates of(93.17%and 79.35%)and(69.4%and 58.35%),and Mean Average Best Overlap(MABO)values of(79.25%and 62.65%),for the VOC2007 and MS-COCO datasets,***,it achieves a Mean Average Precision(mAP)of(84.7%and 81.5%)on both VOC *** experiment findings reveal that our method exceeds previous approaches in terms of overall detection performance,proving its effectiveness.

关键词： Deep neural network deep learning features agglomerative clustering localizations refinement region of interest(ROI) object detection

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Influence of thyroid volume reduction on absorbed dose in ^(131)I therapy studied by using Geant4 Monte Carlo simulation

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Chinese Physics C 2014年第5期38卷 62-68页

作者： ziaur rahman Sikander M Mirza Waheed Arshed Nasir M Mirza Waheed Ahmed Health Physics Division Pakistan Institute of Nuclear Science and Technology Department of Physics and Applied Mathematics Pakistan Institute of Engineering and Applied Sciences

A simulation study has been performed to quantify the effect of volume reduction on the thyroid absorbed dose per decay and to investigate the variation of energy deposition per decay due to β- and γ-activity of 131I with volume/mass of thyroid, for water, ICRP- and ICRU-soft tissue taken as thyroid material. A Monte Carlo model of the thyroid, in the Geant4 radiation transport simulation toolkit was constructed to compute the β- and γ-absorbed dose in the simulated thyroid phantom for various values of its volume. The effect of the size and shape of the thyroid on energy deposition per decay has also been studied by using spherical, ellipsoidal and cylindrical models for the thyroid and varying its volume in 1-25 cm3 range. The relative differences of Geant4 results for different models with each other and MCNP results lie well below 1.870%. The maximum relative difference among the Geant4 estimated results for water with ICRP and ICRU soft tissues is not more than 0.225%. S-values for ellipsoidal, spherical and cylindrical thyroid models were estimated and the relative difference with published results lies within 3.095%. The absorbed fraction values for beta particles show a good agreement with published values within 2.105% deviation. The Geant4 based simulation results of absorbed fractions for gammas again show a good agreement with the corresponding MCNP and EGS4 results （±6.667%） but have 29.032% higher values than that of MIRD calculated values. Consistent with previous studies, the reduction of the thyroid volume is found to have a substantial effect on the absorbed dose. Geant4 simulations confirm dose dependence on the volume/mass of thyroid in agreement with MCNP and EGS4 computed values but are substantially different from MIRD8 data. Therefore, inclusion of size/mass dependence is indicated for 131I radiotherapy of the thyroid.

关键词： mean absorbed dose rate Geant4 Monte Carlo simulation and 131I therapy

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Status of Selective Emitters for p-Type c-Si Solar Cells

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Optics and Photonics Journal 2012年第2期2卷 129-134页

作者： Mohammad ziaur rahman Department of Electrical and Electronic Engineering Ahsanullah University of Science and Technology Tejgaon I/A Dhaka Bangladesh

Crystalline silicon (c-Si) solar cells have the lion share in world PV market. Solar cells made from crystalline silicon have lower conversion efficiency, hence optimization of each process steps are very important. Achieving low-cost photovoltaic energy in the coming years will depend on the development of third-generation solar cells. Given the trend towards these Si materials, the most promising selective emitter methods are identified to date. Current industrial monocrystalline Cz Si solar cells based on screen-printing technology for contact formation and homogeneous emitter have an efficiency potential of around 18.4%. Limitations at the rear side by the fully covering Al-BSF can be changed by selective emitter designs allowing a decoupling and separate optimization of the metallised and non-metallised areas. Several selective emitter concepts that are already in industrial mass production or close to it are presented, and their specialties and status concerning cell performance are demonstrated. Key issues that are considered here are the cost-effectiveness, added complexity, additional benefits, reliability and efficiency potential of each selective emitter tech- niques.

关键词： Solar Cell Selective Emitter Efficiency c-Si

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A Dual-Tree Complex Wavelet Transform-Based Model for Low-Illumination Image Enhancement

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Wuhan University Journal of Natural Sciences 2021年第5期26卷 405-414页

作者： GUAN Yurong Muhammad Aamir ziaur rahman Zaheer Ahmed Dayo Waheed Ahmed Abro Muhammad Ishfaq HU Zhihua Department of Computer Science Huanggang Normal UniversityHuanggang 438000HubeiChina

Image enhancement is a monumental task in the field of computer vision and image *** methods are insufficient for preserving naturalness and minimizing noise in *** article discusses a technique that is based on wavelets for optimizing images taken in ***,the V channel is created by mapping an image’s RGB channel to the HSV color ***,the acquired V channel is decomposed using the dual-tree complex wavelet transform(DT-CWT)in order to recover the concentrated information within its high and low-frequency ***,an adaptive illumination boost technique is used to enhance the visibility of a low-frequency ***,anisotropic diffusion is used to mitigate the high-frequency component’s noise *** improve the results,the image is reconstructed using an inverse DT-CWT and then converted to RGB space using the newly calculated ***,images are white-balanced to remove color *** demonstrate that the proposed approach significantly improves outcomes and outperforms previously reported methods in general.

关键词： image enhancement dual-tree complex wavelet transform(DT-CWT) anisotropic diffusion low-light images

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Nonalcoholic steatohepatitis in nonalcoholic fatty liver disease patients of Bangladesh

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World Journal of Hepatology 2013年第5期5卷 281-287页

作者： Shahinul Alam Sheikh Mohammad Noor-E-Alam ziaur rahman Chowdhury Mahabubul Alam Jahangir Kabir Department of Hepatology Bangabandhu Sheikh Mujib Medical UniversityShahbagDhaka 1000Bangladesh

AIM: To explore the prevalence and risk factors for nonalcoholic steatohepatitis (NASH) in nonalcoholic fatty liver disease (NAFLD) patients. METHODS: We have included 493 patients with sonographic evidence of a fatty change, and 177 of these individuals were evaluated and confirmed after liver biopsy. The exclusion criteria consisted of significant alcohol abuse (< 20 g daily), evidence of hepatitis B and C, evidence of drug-induced fatty liver disease and other specific liver diseases such as hemochromatosis, Wilson’s disease or autoimmune liver disease. The patients were assessed for metabolic syndrome, and biochemical, anthropometric and histopathological evaluations were carried out. The degree of disease activity in the NAFLD patients was evaluated using the NAFLD Activity Score. The data were analyzed by SPSS, version 16.0. RESULTS: Females predominated among the study participants (250, 57.0%), and the mean age was 40.8 ± 10.2 years. The numbers of overweight, obeseⅠ and obese Ⅱ patients were 58 (13.2%), 237 (53.9%) and 93 (21.2%), respectively. However, there were 422 (96.2%) centrally obese patients. NASH was absent in 10 (5.6%) cases, borderline in 92 (52.6%) cases and present in 75 (42.4%) cases. The presence of diabetes could significantly (P = 0.001) differentiate NASH from simple steatosis. The following parameters did not influence the development of NASH: age, sex, basal metabolic index, waist circumference, serum high-density lipoprotein, triglyceride, insulin resistance index, hypertension and metabolic syndrome. The serum gammaglutamyl transpeptidase (GGT) level was significantly higher (P = 0.05, 51.7 ± 32.8 and 40.4 ± 22.6 U/L) in the NASH patients, with a sensitivity of 45% and a specificity of only 68%. The serum alanine aminotransferase and aspartate aminotransferase levels were not able to predict NASH. CONCLUSION: Females were the predominant sufferers of NAFLD in Bangladesh. The prevalence of NASH was high. Diabetes was found to be the

关键词： Fatty liver Gamma-glutamyl transpeptidase Nonalcoholic fatty liver disease Nonalcoholic steatohepatitis Alanine aminotransferase Obesity Basal metabolic index

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Retraction:Modeling Electrical Characteristics of a pn-Junction Silicon Solar Cell Using PSpice

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Smart Grid and Renewable Energy 2012年第2期3卷 133-138页

作者： Mohammad ziaur rahman Shahidul Islam Khan De- partment of Electrical and Electronic Engineering Bangladesh University of Engineering and Technology Dhaka Bangladesh. Department of Electrical and Electronic Engineering Ahsanullah University of Science and Technology Dhaka Bangladesh

Short Retraction Notice The article has been retracted due to the investigation of complaints received against it. The substantial portions of the text came from Luis Casta?er and Santigo Silvestre, " Modelling photovoltaic systems using PSpice".The scientific community takes a very strong view on this matter and we treat all unethical behavior such as plagiarism seriously. This paper published in Vol.3 No.2 133-138, 2012, has been removed from this site.

关键词： Solar Cell PSpice Short Circuit Current Quantum Efficiency Open Circuit Voltage Fill-Factor Efficiency

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