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Exploring the practice of common oral diseases among the patients visiting in the selected dental college and hospital in Bangladesh

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Life Research 2022年第4期5卷 1-5页

作者： Khalid Hasan Pasha md.Fazlul Karim md.mahmudur rahman Ashek Elahi Noor md.Mamunur Rashid Nahid Al Nomann Kazi Golam Mohiuddin Department of Oral&Maxillofacial Surgery Sapporo Dental College and HospitalDhaka-1230Bangladesh Department of Microbiology Kumudini Women’s Medical CollegeMirzapurTangail-1900Bangladesh Department of Gastroenterology Dhaka Medical College and HospitalDhaka-1312Bangladesh Department of Dental Public Health Sapporo Dental College and HospitalDhaka-1230Bangladesh New Labaid Diagnostic Center&Hospital Brahmanbaria-3400Bangladesh Department of Science of Dental Materials Sapporo Dental College and HospitalDhaka-1230Bangladesh

Background:Having the ability to identify potential health risk factors such as lifestyle,ethnicity,health status,and social determinants associated with oral health status risk,health care providers can take an active role in health screening to discover any need for clinical preventive services,including dental preventive services,and can detect health ***:A descriptive type of cross-sectional study was conducted to explore the practice of common oral diseases among the patients visiting in the selected dental college and hospital in Bangladesh from October 2019 to December *** 100 patients were interviewed through a semi-structured questionnaire,followed by an oral examination through a checklist and a face-to-face interview.A systematically random sampling technique was employed to select the study ***:Among them,the(21-30)year age group shows a maximum 20%,whereas the(71-80)year age group represents the minority with only 2%.Among them,56%were male and 44%were *** represent the majority of 26%,whereas others(day laborers)represent only 4%.Decayed teeth remained in 72%of cases,teeth were missing in 31%of cases,and filled teeth were present in 24%of cases.A majority of 71%clean teeth once daily,whereas only 29%clean teeth twice ***,only 30%brush teeth at night and a maximum of 95%brush teeth in the ***,a maximum of 68%use toothpaste and brushes,while only 4%use meswak for cleaning their *** 4%of cases with no debris,51%of cases with less than 1/3rd of the tooth with debris,32%of cases with 1/3rd-2/3rd of the tooth with debris,and 13%of cases with more than 2/3rd of the tooth with debris were ***,about 30%had no calculus,52%less than 1/3rd of tooth,16%in between 1/3rd and 2/3rd of tooth,and 2%more than 2/3rd of the calculus was *** 47%of mild,22%of moderate,6%of severe and 25%had no ***,for treatment purposes,20.69%was advised for scaling,19.66%for

关键词： dental caries abscess broken down root broken down crown decayed missing filled tooth root canal treatment orthopentomogram intra oral periapical cone beam computed tomography body mass index

Capturing transition and non-transition flows with a new shear stress transport model

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Chinese Journal of Aeronautics 2023年第3期36卷 121-136页

作者： md Mizanur rahman School of Mechanical Engineering Hangzhou Dianzi UniversityHangzhou 310018China

A new Shear Stress Transport(SST)k-ω model is devised to integrate salient features of both the non-transitional SST k-ω model and correlation-based γ-Re_(θ) transition *** exceptionally simplified approach is applied to extend the New SST(NSST)model capabilities toward transition/non-transition ***’s stress-intensity factor R_(b)=|-uv|/k can be parameterized with the wall-distance dependent Reynolds number Re_(y)=√ky/v;however,as the Re_(y)is replaced by a“flow-structure-adaptive”parameter R_(μ)=v_(T)/v,the resulting R_(b)is capable of capturing various transition phenomena *** prospective stress-intensity parameter R_(b)=R_(b)(Re_(y),R_(μ))is incorporated in the constitutive relations for eddy-viscosity v_(T) and production term P_(k).The proposed formulation is intrinsically plausible,having a dramatic impact on the prediction of bypass,separation-induced and natural transitions together with non-transitional *** extra viscous-production term P_(k)^(lim) is added with the k-equation to ensure proper generation of k at the viscous sublayer when computing separation-induced transition over a Low-Reynolds Number(LRN)*** demonstrate that the NSST k-ω model maintains an excellent consistency with both SST k-ω and γ-Re_(θ) models.

关键词： γ-Re_(θ)model Non-transition Stress-intensity parameter SST model Transition

Smart Semi-active PID-ACO control strategy for tower vibration reduction in Wind Turbines with MR damper

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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 887-902页

作者： mahmudur rahman Zhi Chao Ong Wen Tong Chong Sabariah Julai Department of Mechanical Engineering Faculty of Engineering University of Malaya

Wind turbine technology is well known around the globe as an eco-friendly and eff ective renewable power source. However, this technology often faces reliability problems due to structural vibration. This study proposes a smart semi-active vibration control system using Magnetorheological (MR) dampers where feedback controllers are optimized with nature-inspired algorithms. Proportional integral derivative (PID) and Proportional integral (PI) controllers are designed to achieve the optimal desired force and current input for MR the damper. PID control parameters are optimized using an Ant colony optimization (ACO) algorithm. The eff ectiveness of the ACO algorithm is validated by comparing its performance with Ziegler-Nichols (Z-N) and particle swarm optimization (PSO). The placement of the MR damper on the tower is also investigated to ensure structural balance and optimal desired force from the MR damper. The simulation results show that the proposed semi-active PID-ACO control strategy can signifi cantly reduce vibration on the wind turbine tower under diff erent frequencies (i.e., 67%, 73%, 79% and 34.4% at 2 Hz, 3 Hz, 4.6 Hz and 6 Hz, respectively) and amplitudes (i.e. 50%, 58% and 67% for 50 N, 80 N, and 100 N, respectively). In this study, the simulation model is validated with an experimental study in terms of natural frequency, mode shape and uncontrolled response at the 1st mode. The proposed PID-ACO control strategy and optimal MR damper position is also implemented on a lab-scaled wind turbine tower model. The results show that the vibration reduction rate is 66% and 73% in the experimental and simulation study, respectively, at the 1st mode.

关键词： ant colony optimization fi nite diff erence method magnetorheological damper PID-ACO controller semiactive control system identifi cation wind turbine tower

Effect of the antenna slot numbers and position on the performance of microwave ablation

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Medicine in Novel Technology and Devices 2023年第4期20卷 105-113页

作者： Sabiha Binte Aziz md Rejvi Kaysir md Jahirul Islam Torikul Islam mahmudur rahman Department of Biomedical Engineering(BME) Khulna University of Engineering&TechnologyKhulna-9230Bangladesh Photonics Research Group Department of EEEKhulna University of Engineering&TechnologyKhulna-9230Bangladesh Department of Electrical and Computer Engineering Waterloo Institute for NanotechnologyUniversity of Waterloo200 University AveWaterlooONCanada Department of Biomedical Engineering(BME) New Jersey Institute of TechnologyNewarkNJUSA Department of Electrical and Electronic Engineering Dhaka University of Engineering&TechnologyGazipur 1707Bangladesh

Microwave ablation(MWA)is a type of thermal ablation used for cancer treatment in interventional *** induce localized tissue heating MWA employs electromagnetic waves within the microwave energy spectrum,which is done by the precisely designed *** study substantially emphasizes the design and performance ameliorating of slot(both single and double)antennae and compares the results with conventional monopole antennae in terms of temperature distribution,specific absorption ratio(SAR),and thermal tissue damage *** simulation has been done in COMSOL by solving the Bioheat equation along with Maxwell electromagnetic equations using the finite element *** simulation results reveal that the double-slot antenna has the most accurate and directional heat dissipation for liver tumors as well as the highest tissue damage rate and *** highest SAR was found to be 3500 W/kg and 3350 W/kg at the implant depth of 61 mm and 63 mm for double and single-slot antennae,*** addition,the fastest tissue damage occurred near the upper slot of the double-slot *** study helps to understand the basic design parameters for enhancing single and doubleslot antennae performance.

关键词： Microwave ablation(MWA) Finite element method(FEM) Liver tumor Microwave antenna Specific absorption rate(SAR)

Test and performance optimization of nozzle inclination angle and swirl combustor in a low-tar biomass gasifier:a biomass power generation system perspective

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Carbon Resources Conversion 2022年第2期5卷 139-149页

作者： md Mashiur rahman Agricultural Engineering Division Regional Agricultural Research StationBangladesh Agricultural Research InstituteJamalpur2000Bangladesh DTU Chemical Engineering Technical University of Denmark(DTU)Frederiksborgvej 399DK 4000 RoskildeDenmark

A nozzle inclination angle and swirl combustor inside the low-tar biomass(LTB)gasifier reactor were tested and optimized to evaluate these effects on tar reduction to design tar-free producer *** tar reduction process is mainly based on the concept of a swirling flow created by the nozzle inclination angle,with the inclination angle of 55◦to the radial line,allowing good mixing between pyrolysis gases and gasifying agents.A separate swirl combustor has created large internal annular and reverses flow zones with the help of swirl flow,resulting in homogenized temperature inside the combustor and providing longer residence time;both have a positive effect on the combustion of mixed gasifying air-pyrolysis gases by the thermal cracking in the partial oxidation *** ratio(RR)and combustion degree of volatiles are the two optimization parameters for evaluating the performance of NIA and swirl *** result observed that outstanding tar reduction occurred in this novel *** 86.5 and 12.8%of tar compounds are broken down in the partial oxidation zone and pyrolysis zone using the novel swirl combustor and NIA,respectively;gas outlet has observed producer gas having tar concentration of less than 1%.The optimization results reveal that a lower recycling ratio(recycle gas/gasifying air)and a higher combustion degree of volatiles perform better in biomass ***,this system generated producer gas with the tar concentration at an extremely low level of 7.4 mg/Nm^(3)for a biomass moisture content of 9%and appeared the lower heating value of 4.6–5.1 MJ/Nm^(3).This lower tar concentration might be directly coupled with an internal combustion engine or a gas turbine for power generation.

关键词： Biomass gasification Downdraft moving bed gasifier Nozzle inclination angle Swirl combustor Swirl flow Tar Reduction

Influence of soil physicochemical properties,particle size fractions and mineralogy on the leaching potentials of arsenic and antimony in abandoned mine soils

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Pedosphere 2023年第5期33卷 744-753页

作者： A.S.M.Fazle BARI Dane LAMB Geoff R.MACFARLANE Mohammad mahmudur rahman Global Centre for Environmental Remediation(GCER) College of EngineeringScience and EnvironmentThe University of NewcastleCallaghanNSW 2308Australia Department of Soil Science Sher-e-Bangla Agricultural UniversityDhaka 1207Bangladesh Chemical and Environmental Engineering School of EngineeringRMIT UniversityMelbourneVictoria 3000Australia School of Environmental and Life Sciences The University of NewcastleCallaghanNSW 2308Australia

At abandoned mine sites,arsenic(As)-and antimony(Sb)-enriched soils are often disposed of through onsite burial or *** highly weathered mine sites,the mobility of As and Sb is typically controlled by iron(Fe)(III)/Fe(II)phases;thus,the suitability of such disposal methods and appropriate testing techniques are *** the present study,leaching potentials of As and Sb were examined using the toxicity characteristic leaching procedure(TCLP),waste extraction test(WET),and WET-extended procedure(WET-EXT)at three abandoned mine site soils in *** leached concentration of As regularly exceeded USEPA criteria(5 mg L^(-1)).The highest leached concentrations of As and Sb were observed in the finest particle size fraction(<0.053 mm)by WET-EXT(1040 mg L^(-1)for As and 21.10 mg L^(-1)for Sb)followed by WET(800 mg L^(-1)for As and 20.90 mg L^(-1)for Sb).The TCLP method resulted in the lowest concentrations of leached As(0.0009 mg L^(-1))and Sb(0.0003 mg L^(-1)).Crystalline and amorphous As-bearing Fe oxides were the main phases in the soils ***,the best correlations of leached As determined by TCLP(0.832),WET(0.944),and WET-EXT(0.961)were found with the non-specifically sorbed(NS1)As *** mineralogical and sequential extraction data clearly indicate the dominant role of Fe geochemistry in controlling leachability of As and *** TCLP method was unlikely to be suitable for assessing leachability,as it exhibited no relationship with leachable Fe and substantially lower leached As and Sb than the other two *** the high to extremely high leachable As and Sb concentrations,most of the soil samples would not be recommended for placement in capping works,old shafts,or reduction systems(e.g.,collection in drainage basins).

关键词： particle size fraction sequential extraction toxic element toxicity characteristic leaching procedure waste extraction test

Behaviour of self-centring shear walls——A state of the art review

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Frontiers of Structural and Civil Engineering 2023年第1期17卷 53-77页

作者： Mehdi JAVADI Reza HASSANLI md Mizanur rahman md Rajibul KARIM UniSA STEM University of South AustraliaAdelaide 5095Australia

The application of unbonded post-tensioning (PT) in structural walls has led to the development of advanced self-centring (rocking) shear wall systems that has significant advantages, including accelerated construction due to the incorporation of prefabricated elements and segmental construction for different materials (e.g., concrete, masonry, and timber), reduced residual drifts, and little damage upon extreme seismic and wind loads. Concrete, masonry, and timber are often used for the construction of unbonded PT structural wall systems. Despite extensive research since the 1980s, there are no well-established design guidelines available on the shear wall configuration with the required energy dissipation system, joint’s locations and acceptance criteria for shear sliding, confinement, seismic performance factors, PT loss, PT force range and residual drifts of shear walls subjected to lateral loads. In this research a comprehensive state-of-the-art literature review was performed on self-centring shear wall system. An extensive study was carried out to collect a database of 100 concrete, masonry, and self-centring shear wall tests from the literature. The established database was then used to review shear walls’ configurations, material, and components to benchmark requirements applicable for design purposes. The behaviour of concrete, masonry and timber shear walls were compared and critically analysed. The general behaviour, force-displacement performance of the walls, ductility, and seismic response factors, were critically reviewed and analysed for different self-centring wall systems to understand the effect of different parameters including configurations of the walls, material used for construction of the wall (concrete, masonry, timber) and axial stress ratio. The outcome of this research can be used to better understand the behaviour of self-centring wall system in order to develop design guidelines for such walls.

关键词： self-centring shear walls rocking walls energy dissipation seismic performance factors PT loss residual drift

Self-centring segmental retaining walls—A new construction system for retaining walls

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Frontiers of Structural and Civil Engineering 2021年第4期15卷 980-1000页

作者： Mehdi JAVADI Reza HASSANLI md Mizanur rahman md Rajibul KARIM UniSA STEM University of South AustraliaMawson Lakes5095Australia

This paper reports on an experimental study on a new self-centring retaining wall *** post-tensioned segmental retaining walls(PSRWs)were experimentally *** of the walls was constructed using seven T-shaped concrete segments with a dry *** walls were tested under incrementally increasing cyclic lateral *** effect of the wall height,levels of post-tensioning(PT)force,and bonded versus unbonded condition of PT reinforcement on the structural behavior of the PSRWs was *** results showed that such PSRWs are structurally adequate for water retaining *** to the results,increasing the wall height decreases initial strength but increases the deformation capacity of the *** larger deformation capacity and ductility of PSRW make it a suitable structural system for fluctuating loads or deformation,e.g.,*** was also found that increasing the PT force increases the wall’s stiffness;however,reduces its *** residual drift and the extent of damage of the unbonded PSRWs were significantly smaller than those of the bonded *** suggest that this newly developed self-centring retaining wall can be a suitable structural system to retain lateral *** to its unique deformation capacity and self-centring behavior,it can potentially be used for seawall application.

关键词： retaining wall segmental precast concrete unbonded post-tensioning water retaining wall seawall

The link between intracellular calcium signaling and exosomal PD-L1 in cancer progression and immunotherapy

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Genes & Diseases 2024年第1期11卷 321-334页

作者： md Rakibul Alam md Mizanur rahman Zhiguo Li Department of Toxicology and Cancer Biology College of MedicineUniversity of KentuckyLexingtonKY 40506USA Department of Medicine(Nephrology) Faculty of Medicine and DentistryUniversity of AlbertaEdmontonAlberta T6E2H7Canada

Exosomes are small membrane vesicles containing microRNA,RNA,DNA fragments,and proteins that are transferred from donor cells to recipient *** cells release exo-somes to reprogram the factors associated with the tumor microenvironment(TME)causing tu-mor metastasis and immune *** evidence revealed that cancer cell-derived exosomes carry immune inhibitory molecule program death ligand 1(PD-L1)that binds with re-ceptor program death protein 1(PD-1)and promote tumor progression by escaping immune ***,some FDA-approved monoclonal antibodies are clinicallyused for cancer treatment by blocking PD-1/PD-L1 *** notable treatment outcomes,some pa-tients show poor drug *** PD-L1 plays a vital role in lowering the treatment response,showing resistance to PD-1/PD-L1 blockage therapy through recapitulating the ef-fect of cell surface *** enhance therapeutic response,inhibition of exosomal PD-L1 is *** signaling is the central regulator of tumorigenesis and can regulate exosome biogenesis and secretion by modulating Rab GTPase family and membrane fusion ***-mune checkpoints are also connected with calcium signaling and calcium channel blockers like amlodipine,nifedipine,lercanidipine,diltiazem,and verapamil were also reported to suppress cellular PD-L1 ***,to enhance the PD-1/PD-L1 blockage therapy response,the reduction of exosomal PD-L1 secretion from cancer cells is in our therapeutic *** this review,we proposed a therapeutic strategy by targeting calcium signaling to inhibit the expression of PD-L1-containing exosome levels that could reduce the anti-PD-1/PD-L1 therapy resistance and increase the patient's drug response rate.

关键词： Calcium signaling CD8^(+)T cells Exosomal PD-L1 Exosomes biogenesis Immunosuppression Immunotherapy