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Article
Publication date: 24 October 2020

Maryam Mogheiseh, Reza Hasanzadeh Ghasemi and Reza Soheilifard

The purpose of this paper is to compare the stability of the three nanocarriers created by DNA origami method with different positions and numbers of crossovers

135

Abstract

Purpose

The purpose of this paper is to compare the stability of the three nanocarriers created by DNA origami method with different positions and numbers of crossovers

Design/methodology/approach

Nanocarriers are attractive components among a variety of nanostructures created by DNA origami and can have numerous applications in mechanical and medical engineering. For this reason, the current study compares three nanotubes with different positions and numbers of crossovers created by DNA origami method that can be utilized as nanocarriers. To investigate the structures, the DNA nanocarriers are studied at the human body temperature 310 K. Molecular dynamics simulations are used for this study. For a quantitative analysis of DNA nanocarriers, the areas of three hexagons at three different sites in each of the nanotubes are investigated. The results indicate that the number and position of crossovers are among the significant factors in the structure stability of nanocarriers. The analyses also revealed that although adding crossovers in locations with fewer crossovers increase structural stability, the position of crossovers can have different effects on the stability. DNA origami-based nanocarriers can be implemented in drug delivery, allow the nanocargoes to pass various surfaces and act as filters for passing cargoes of different dimensions and chemical structures.

Findings

The results indicate that the number and position of crossovers are among the significant factors in the structure stability of nanocarriers

Originality/value

In this paper, the stability of DNA origami nanocarriers with different positions and numbers of crossovers was investigated.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 2
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 28 March 2019

Reza Ghasemi, Hamid Reza Habibi, Masomeh Ghasemlo and Meisam Karami

The purpose of this paper, as an empirical investigation of a contingency theory, is to examine the relationship between technology (as a contingent variable) and management…

1891

Abstract

Purpose

The purpose of this paper, as an empirical investigation of a contingency theory, is to examine the relationship between technology (as a contingent variable) and management accounting system (MAS) characteristics on managerial performance. The main focus of this study is on the four information characteristics of MAS – scope, integration, aggregation and timeliness.

Design/methodology/approach

Based on the MAS characteristics defined by Chenhall and Morris, a contingency-based “intervening” model is proposed in which MAS plays a significant intervening role between technology (TECH) and managerial performance. Using survey data from managers in Iranian financial organizations and PLS–structural equation model analysis, the MAS characteristics are collectively analyzed in relation to technology and managerial performance.

Findings

The study uncovered the existence of direct relationships between technology and MAS, and between MAS and managerial performance. The study also confirmed that the relationship between technology and managerial performance is mediated by MAS. The findings provide valuable insight to guide managers in financial organizations to improve their performance through suitable MAS by applying new technologies and considering internal and environmental factors. Recommendations on how to improve MAS and managerial performance are provided accordingly.

Originality/value

Previous research studies show that there is no unique and universal MAS for all organizations, since this depends on internal firm characteristics and environmental features. However, there has been a lack of empirical evidence on MAS research studies in the service organizations.

Details

Journal of Accounting in Emerging Economies, vol. 9 no. 2
Type: Research Article
ISSN: 2042-1168

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Available. Content available
430

Abstract

Details

Research Journal of Textile and Apparel, vol. 27 no. 3
Type: Research Article
ISSN: 1560-6074

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Article
Publication date: 22 October 2024

Raheleh Khosravi, Maryam Mogheiseh and Reza Hasanzadeh Ghasemi

The present study aims to design and simulate various types of deoxyribonucleic acid (DNA) origami-based nanopores and explore their stability under different temperatures and…

39

Abstract

Purpose

The present study aims to design and simulate various types of deoxyribonucleic acid (DNA) origami-based nanopores and explore their stability under different temperatures and constraints. To create DNA origami nanopores, both one-layer and two-layer structures can be utilized.

Design/methodology/approach

One of the key applications of DNA origami structures involves the creation of nanopores, which have garnered significant interest for their diverse applications across multiple scientific disciplines. DNA origami nanopores can be studied individually and in combination with other structures. The structural stability of these nanopores across various temperature conditions is crucial for enabling the passage of diverse payloads.

Findings

Comparing these DNA origami structures can provide valuable insights into the performance of these nanopores under different conditions. The results indicate that two-layer nanopores exhibit better structural stability under various temperatures compared to one-layer nanopores. Additionally, small structural changes in two-layer nanopores enable them to maintain stability even at high temperatures.

Originality/value

In this paper, various DNA origami-based nanopores were designed and simulated, focusing specifically on one-layer and two-layer configurations. The two-layer nanopore consistently exhibited superior stability across both free and restrained scenarios, undergoing fewer structural changes compared to the one-layer nanopore. As temperatures increased, the two-layer nanopore remained less susceptible to deformation, maintaining closer to its original shape. Moreover, in the free scenario, the geometric shape of the two-layer nanopore demonstrated fewer variations than the one-layer nanopore.

Details

Multidiscipline Modeling in Materials and Structures, vol. 21 no. 1
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 1 August 2016

Reza Ghasemi, Noor Azmi Mohamad, Meisam Karami, Norkhairul Hafiz Bajuri and Ezzatollah Asgharizade

This study aims to examine the effect of interaction between market competition and management accounting system (MAS) characteristics on managerial performance. Scope of the…

2190

Abstract

Purpose

This study aims to examine the effect of interaction between market competition and management accounting system (MAS) characteristics on managerial performance. Scope of the study is concentrated on Iranian financial organizations and managers of these organizations were identified as respondents for the questionnaire survey.

Design/methodology/approach

This study used the SmartPLS to analyze the data, and the model of the study was estimated with structural equation modeling (SEM). It follows the recommended two-stage analytical procedures of SEM: assessing confirmatory measurement models (factor analysis) and confirmatory structural models (path analysis).

Findings

The study uncovered the existence of direct relationships between competition and MAS, and between MAS and managerial performance. The study also confirmed that the relationship between competition and managerial performance is mediated by MAS.

Research limitations/implications

The findings provide valuable insights to guide managers in financial organizations to improve their performance through suitable MAS by considering internal and environmental factors. Recommendations on how to improve MAS and managerial performance are provided accordingly.

Originality/value

Prior researches confirm that there is no unique and universal MAS for all organizations, as this depends on internal firm characteristics and environmental features. However, there has been a lack of empirical evidence on MAS researches in the service organizations.

Details

International Journal of Accounting and Information Management, vol. 24 no. 3
Type: Research Article
ISSN: 1834-7649

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Article
Publication date: 2 May 2017

Amirmahdi Ghasemi, R. Nikbakhti, Amirreza Ghasemi, Faraz Hedayati and Amir Malvandi

A numerical method is developed to capture the interaction of solid object with two-phase flow with high density ratios. The current computational tool would be the first step of…

196

Abstract

Purpose

A numerical method is developed to capture the interaction of solid object with two-phase flow with high density ratios. The current computational tool would be the first step of accurate modeling of wave energy converters in which the immense energy of the ocean can be extracted at low cost.

Design/methodology/approach

The full two-dimensional Navier–Stokes equations are discretized on a regular structured grid, and the two-step projection method along with multi-processing (OpenMP) is used to efficiently solve the flow equations. The level set and the immersed boundary methods are used to capture the free surface of a fluid and a solid object, respectively. The full two-dimensional Navier–Stokes equations are solved on a regular structured grid to resolve the flow field. Level set and immersed boundary methods are used to capture the free surface of liquid and solid object, respectively. A proper contact angle between the solid object and the fluid is used to enhance the accuracy of the advection of the mass and momentum of the fluids in three-phase cells.

Findings

The computational tool is verified based on numerical and experimental data with two scenarios: a cylinder falling into a rectangular domain due to gravity and a dam breaking in the presence of a fixed obstacle. In the former validation simulation, the accuracy of the immersed boundary method is verified. However, the accuracy of the level set method while the computational tool can model the high-density ratio is confirmed in the dam-breaking simulation. The results obtained from the current method are in good agreement with experimental data and other numerical studies.

Practical/implications

The computational tool is capable of being parallelized to reduce the computational cost; therefore, an OpenMP is used to solve the flow equations. Its application is seen in the following: wind energy conversion, interaction of solid object such as wind turbine with water waves, etc.

Originality/value

A high efficient CFD approach method is introduced to capture the interaction of solid object with a two-phase flow where they have high-density ratio. The current method has the ability to efficiently be parallelized.

Details

Engineering Computations, vol. 34 no. 3
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 9 August 2024

Mohammad Reza Jalilvand and Hamed Ghasemi

Augmented reality (AR) is revolutionizing the tourism and hospitality industry by offering immersive experiences as well as creating more engaging, informative and accessible…

390

Abstract

Purpose

Augmented reality (AR) is revolutionizing the tourism and hospitality industry by offering immersive experiences as well as creating more engaging, informative and accessible travel experiences that attract tourists from around the globe. From virtual tours and immersive historical site recreations to navigation assistance and cultural education, AR technology is transforming the way we explore and interact with the destinations. This study aims to identify benefits, risks, tools and techniques of AR in the tourism and hospitality literature.

Design/methodology/approach

The authors conducted a systematic literature review to answer six research questions. The authors also identified 33 primary studies, dated from January 2010 to February 2024 and coded them via a thematic analysis. Related studies were obtained through searching in Web of Science and Scopus.

Findings

The results identified nine themes for benefits, eight themes for risks/disadvantages and four tools and applications-related themes. Through the thematic analysis, the major benefits of AR in the tourism and hospitality were found to be differentiated travel experiences, improved performance of tourism value chain, more effective marketing efforts of tourism businesses, enhanced tourists’ engagement, enhanced performance of tourism destinations, stimulated behavioral intentions, tourist empowerment and providing more value, interactivity and integrity. Furthermore, eight risks were identified: physical, privacy and security, social, service failure, technical, psychological, managerial, information and knowledge gaps. The authors also recognized four tools and applications-related themes, namely, AR-enabled tools, AR applications, AR-enabled apps and AR-based techniques.

Originality/value

To the best of the authors’ knowledge, this review provides the first systematic exploration of the existing literature on usage of AR in the context of tourism and hospitality value chain.

Details

Journal of Science and Technology Policy Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2053-4620

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Article
Publication date: 12 June 2017

Meysam Amini, Esmaeil GhasemiKafrudi, Mohammad Reza Habibi, Azin Ahmadi and Akram HosseinNia

Due to the extensive industrial applications of stagnation flow problems, the present work aims to investigate the magnetohydrodynamics (MHD) flow and heat transfer of a magnetite…

101

Abstract

Purpose

Due to the extensive industrial applications of stagnation flow problems, the present work aims to investigate the magnetohydrodynamics (MHD) flow and heat transfer of a magnetite nanofluid (here Fe3O4–water nanofluid) impinging a flat porous plate under the effects of a non-uniform magnetic field and chemical reaction with variable reaction rate.

Design/methodology/approach

Similarity transformations are applied to reduce the governing partial differential equations with boundary conditions into a system of ordinary differential equations over a semi-infinite domain. The modified fourth-order Runge–Kutta method with the shooting technique which is developed for unbounded domains is conducted to give approximate solutions of the problem, which are then verified by results of other researchers, showing very good agreements.

Findings

The effects of the volume fraction of nanoparticles, permeability, magnetic field, chemical reaction and Schmidt number on velocity, temperature and concentration fields are examined and graphically illustrated. It was found that fluid velocity and temperature fields are affected strongly by the types of nanoparticles. Moreover, magnetic field and radiation have strong effects on velocity and temperature fields, fluid velocity increases and thickness of the velocity boundary layer decreases as magnetic parameter M increases. The results also showed that the thickness of the concentration boundary layer decreases with an increase in the Schmidt number, as well as an increase in the chemical reaction coefficient.

Research limitations/implications

The thermophysical properties of the magnetite nanofluid (Fe3O4–water nanofluid) in different conditions should be checked.

Practical implications

Stagnation flow of viscous fluid is important due to its vast industrial applications, such as the flows over the tips of rockets, aircrafts, submarines and oil ships. Moreover, nanofluid, a liquid containing a dispersion of sub-micronic solid particles (nanoparticles) with typical length of the order of 1-50 nm, showed abnormal convective heat transfer enhancement, which is remarkable.

Originality/value

The major novelty of the present work corresponds to utilization of a magnetite nanofluid (Fe3O4–water nanofluid) in a stagnation flow influenced by chemical reaction and magnetic field. It should be noted that in addition to a variable chemical reaction, the permeability is non-uniform, while the imposed magnetic field also varies along the sheet. These, all, make the present work rather original.

Details

World Journal of Engineering, vol. 14 no. 3
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 14 September 2010

Abdollah Ghasemi Pirbalouti, Arian Asadpoor, Behzad Hamedi and Ahmad Reza Golparvar

Plant materials continue to play a major role in primary health care as therapeutic remedies in many developing countries. Medicinal herbs contain physiologically active…

1425

Abstract

Purpose

Plant materials continue to play a major role in primary health care as therapeutic remedies in many developing countries. Medicinal herbs contain physiologically active principles that over the years have been exploited in traditional medicine for the treatment of various ailments as they contain antimicrobial properties. This paper aims to determine the antibacterial activity of Iranian endemic plants.

Design/methodology/approach

Antibacterial activities of ethanol extract and essential oil of ten Iranian folklore herbs including Heracleum lasiopetalum Boiss., Hypericum scabrum L., Thymus daenensis Celak., Ziziphora teniur L., Echiophora platyloba L., Dracocephalum multicaule Benth., Kelussia odoratissima Mozff., Mentha longifolia Hudson., Achillea kellalensis Boiss. and Arnebia euchroma (Royle.) Johnston. were investigated against Yersinia enterocolitica PTCC 1151 by agar disc diffusion and serial dilution assays.

Findings

Most of the extracts and essential oils showed some antibacterial activity against the tested bacteria with the diameter of inhibition zone ranging between 9 and 16 mm. Of the plants studied, the most active extracts were those obtained from essential oil of H. lasiopetalum fruits and ethanol extract of A. euchroma roots. The MIC values for active extract and essential oil ranged between 0.039 and 0.156 mg/ml.

Practical implications

The results obtained appeared to confirm the antibacterial potential of the plants investigated.

Originality/value

The essential oil <0.039 mg/ml of H. lasiopetalum fruits could be used as natural antibacterial agent Y. enterocolitica in the food preservation and human health.

Details

Nutrition & Food Science, vol. 40 no. 5
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 4 March 2014

Hamid Reza Golmakani and Morteza Pouresmaeeli

The purpose of this paper is to determine optimal replacement threshold and optimal inspection interval for an item subjected to condition-based maintenance (CBM). The primarily…

1483

Abstract

Purpose

The purpose of this paper is to determine optimal replacement threshold and optimal inspection interval for an item subjected to condition-based maintenance (CBM). The primarily assumption is that the item's failure replacement cost depends on the item's degradation state at which failure occurs and/or the time the item fails. The cost of inspection is also taken into account.

Design/methodology/approach

The control limit replacement policy framework, already reported by some research referred to in this paper, is first extended to include the non-decreasing failure replacement cost assumption. Then, for alternative inspection intervals, replacement thresholds together with their associated total cost including the inspection cost are computed. By comparing the total costs, the optimal inspection interval and its corresponding optimal replacement threshold are simultaneously identified.

Findings

The mathematical formulation required for the determination of optimal replacement threshold and optimal inspection interval for an item subjected to CBM under the assumption of non-decreasing failure cost is provided.

Practical implications

In some practical situations where CBM is implemented, the failure replacement cost may depend on the time the failure happens and/or may depend on the system's degradation state. In addition, inspections often incur cost. Under such circumstances, findings of this paper can be utilized for the determination of optimal replacement threshold and optimal inspection interval for the underlying system.

Originality/value

Using the approach proposed in this paper, one could obtain the optimal replacement threshold and the optimal inspection interval for a system subjected to CBM.

Details

Journal of Quality in Maintenance Engineering, vol. 20 no. 1
Type: Research Article
ISSN: 1355-2511

Keywords

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