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Herbal medicine has been used for the management of complications of diabetes. The purpose of this paper is to examine the anti-diabetic effects of Achillea millefolium extract on diabetic rats.

To this aim, 32 male Wistar rats were randomly assigned into four groups in which each group comprised eight rats. The four experimental groups were as follows: control group, diabetic control (DC) group (STZ; 50 mg/kg), diabetic rats, receiving 250 mg/kg hydro-alcoholic extract of the A. millefolium (DAM) and diabetic rats, receiving 5 mg/kg glibenclamide (DG). After 21 days of the treatment course, tissues of the kidney and blood samples were collected for histopathological, biochemical and molecular analysis.

The concentration of malondialdehyde (MDA) and glucose serum were markedly reduced in the DC group while significantly increased in DG and DAM groups (1.11 ± 0.57 to 19.4 ± 3.5 and 17.8 ± 1.2 p = 0.002 and 325 ± 0.18 to 223 ± 0.11 and 211 ± 0.32 p = 0.02, respectively). Also, the activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) were markedly reduced in the DC group while significantly increased in DAM and DG groups (9.1 ± 2.21 to 18.7 ± 3.81 and 14.9 ± 3.1 p = 0.03 and p = 0.02, respectively). The concentrations of creatinine, blood urea nitrogen (BUN) and urea were substantially decreased in DAM and DG groups as compared with the DC group (0.49 ± 0.02 to 0.27 ± 0.01 and 0.25 ± 0.01 p = 0.01, 15.6 ± 2.1 to 7.2 ± 0.68 and 8.6 ± 1.2 p = 0.02 and 114 ± 9.4 to 59.8 ± 5.2 and 64 ± 5.2 p = 0.03, respectively). Also, Bcl-2-associated X protein (BAX) expression was significantly decreased in DAM and DG groups as compared with the DC group (1.3 ± 0.32 to 0.91 ± 0.03 and 0.93 ± 0.02 p = <0.01) and Bcl-2 expression were significantly increased in DAM and DG groups as compared with the DC group (0.42 ± 0.05 to 0.88 ± 0.07 and 0.85 ± 0.06 p = 0.01).

Diabetes led to degenerative damages in the kidney of rats and increased the mRNA level of Bax, while treatment with A. millefolium could protect the kidney tissue against diabetes complications and increased the mRNA expression of Bcl-2. This study indicated that A. millefolium extracts not only improves renal function as a result of anti-oxidant activity but also modulates some biochemical factors in diabetic rats.

A boiling surface with different initial roughness and under various nanoparticles volume fractions was studied in present work.

Develop a correlation and sensitivity analysis.

The results showed that for small (7.3 nm) and much larger (about 2,000 nm) surface roughness, compared to nanoparticle size of around 25 nm, the heat transfer rate of nanofluid diminishes relative to that of base fluid. The results also demonstrated that the boiling heat transfer rate is reduced by increasing the concentration of nanoparticles. For larger boiling surface roughness (480 nm) and nanoparticles volume fractions of less than 0.1 Vol.%, the value of heat transfer increases with the increase of nanoparticles concentration; and for those of more than 0.1 Vol.%, heat transfer rate decreases by adding more nanoparticles, significantly.

Finally, an equation was presented for estimating the wall superheat and the C_sf coefficient in terms of mentioned parameters.

The purpose of this study is simulation of of polymer electrolyte membrane fuel cell. Proton-exchange membrane fuel cells are promising power sources for use in power plants and vehicles. These fuel cells provide a high level of energy efficiency at low temperature without any pollution. The convection inside the cell plays a key role in the electrochemical reactions and the performance of the cell. Accordingly, the transport processes in these cells have been investigated thoroughly in previous studies that also carried out functional modeling.

A multi-phase model was used to study the limitations of the reactions and their impact on the performance of the cell. The governing equations (conservation of mass, momentum and particle transport) were solved by computational fluid dynamics (CFD) (ANSYS fluent) using appropriate source terms. The two-phase flow in the fuel cell was simulated three-dimensionally under steady-state conditions. The flow of water inside the cell was also simulated at high-current density.

The simulation results suggested that the porosity of the gas diffusion layer (GDL) is one of the most important design parameters with a significant impact on the current density limitation and, consequently, on the cell performance.

This study was mainly focused on the two-phase analysis of the steady flow in the fuel cell and on investigating the impacts of a two-phase flow on the performance of the cell and also on the flow in the GDL, the membrane and the catalyst layer using the CFD.

This paper aims to propose a new nonlinear function estimation fuzzy system as a novel statistical approach to estimate nanofluids’ thermal conductivity.

A fuzzy system having a product inference engine, a singleton fuzzifier, a center average defuzzifier and Gaussian membership functions is proposed for this purpose.

Results indicate that the proposed fuzzy system can predict the thermal conductivity of Al₂O₃/paraffin nanofluid with appropriate precision and generalization and it also outperforms the classic interpolation methods.

A new nonlinear function estimation fuzzy system was introduced as a novel statistical approach to estimate nanofluids’ thermal conductivity for the first time.

The purpose of this study is to develop a model to understand the relationships among technology, organizational and environmental (TOE) contexts, intention to adopt cloud computing (IACC) and actual usage of cloud computing (AUCC) in small and medium enterprises (SMEs) in Malaysia as a developing country. More specifically, this paper seeks to explore the mediation effect of IACC on the relationship between TOE context and AUCC.

A positivist research approach was selected for this study. Drawing largely upon the TOE framework, this study uses survey data from 209 Malaysian SMEs. Structural equation modelling (SEM) based on partial least squares (PLS) was used to assess the structural relations of the research model.

The results of the structural model show that data security, technology readiness, top management support, competitive pressure and innovativeness are the most significant factors in predicting the adoption of cloud computing in Malaysian SMEs. Further, the results indicate that intention to adopt cloud computing can play a mediating role between TOE factors and the actual usage of cloud computing.

The focus upon Malaysian SMEs may diminish the generalizability of the findings. This study provides profound insight into the management and foundation of cloud computing, different types of cloud services and deployment models that could facilitate the management of enterprise strategic resources and contribute to the performance improvement. This study also provides another important implication for practitioners regarding the absolute necessity of value drivers’ identification within enterprise and understand the causal relationships, which are vital in driving those values.

This study provides several practical guidance for practitioners in deploying cloud services which are most suitable option for their specific technology requirement in their enterprise to enjoy the full benefits of their intangible assets. Another significant implication of this study lies in the fact that it may require a different emphasis on nature and adoption design when there is a higher level of stress on technology-related and cloud computing resources.

This study contributes to the extant literature by developing an integrative model to identify how a wide set of contextual factors can determine the intention to adopt cloud computing and, in turn, influence the actual usage of cloud computing in SMEs in Malaysia as a developing country.

This paper aims to study the fluid flow and heat transfer through a spiral double-pipe heat exchanger. Nowadays using spiral double-pipe heat exchangers has become popular in different industrial segments due to its complex and spiral structure, which causes an enhancement in heat transfer.

In these heat exchangers, by converting the fluid motion to the secondary motion, the heat transfer coefficient is greater than that of the straight double-pipe heat exchangers and cause increased heat transfer between fluids.

The present study, by using the Fluent software and nanofluid heat transfer simulation in a spiral double-tube heat exchanger, investigates the effects of operating parameters including fluid inlet velocity, volume fraction of nanoparticles, type of nanoparticles and fluid inlet temperature on heat transfer efficiency.

After presenting the results derived from the fluid numerical simulation and finding the optimal performance conditions using a genetic algorithm, it was found that water–Al₂O₃ and water–SiO₂ nanofluids are the best choices for the Reynolds numbers ranging from 10,551 to 17,220 and 17,220 to 31,910, respectively.

To respect the patients’ physical privacy, they should be provided with proper clothing that prevents the exposure of unnecessary parts of the body. The purpose of this paper is to evaluate patient satisfaction upon wearing customized, high-coverage, procedure-specific dresses.

New designs of clothing adapted for different kinds of procedures, and offering a good coverage of the body and easy access to the required parts were compared with regular patient clothing. Patients from six different wards of a university hospital filled out a questionnaire inquiring about general and demographic variables, and patient satisfaction was evaluated based on six main features of the clothing design. p<0.005 was considered as the level of statistical significance.

Overall, 256 patients were entered into the regular-design and new-design groups (n=128 in each). In Group 1 (regular design), the rate of dissatisfaction was about 98, 84, 84, 78, 77 and 38 percent for ease of wearing, comfort, design, material, coverage level and size, respectively. In Group 2 (new design), the highest satisfaction rates were associated with ease of wearing, size, coverage level, material, design and comfort as 93.7, 91.4, 89.9, 87.1, 86, and 80.5 percent, respectively.

The present study is the first to investigate customized patient clothing and demonstrated that these clothes can improve the patients’ satisfaction in terms of coverage, comfort, design and size.

Water/Al₂O₃ nanofluid with volume fractions of 0, 0.3 and 0.06 was investigated inside a rectangular microchannel. Jet injection of nanofluid was used to enhance the heat transfer under a homogeneous magnetic field with the strengths of Ha = 0, 20 and 40. Both slip velocity and no-slip boundary conditions were used.

The laminar flow was studied using Reynolds numbers of 1, 10 and 50. The results showed that in creep motion state, the constricted cross section caused by fluid jet is not observable and the rise of axial velocity level is only because of the presence of additional size of the microchannel. By increasing the strength of the magnetic field and because of the rise of the Lorentz force, the motion of fluid layers on each other becomes limited.

Because of the limitation of sudden changes of fluid in jet injection areas, the magnetic force compresses the fluid to the bottom wall, and this behavior limits the vertical velocity gradients. In the absence of a magnetic field and under the influence of the velocity boundary layer, the fluid motion has more variations. In creeping velocities of fluid, the presence or absence of the magnetic field does not have an essential effect on Nusselt number enhancement.

In lower velocities of fluid, the effect of the jet is not significant, and the thermal boundary layer affects the entire temperature field. In this case, for Hartmann numbers of 40 and 0, changing the Nusselt number on the heated wall is similar.

Meeting the patients' requirements as customers of the health care sector is crucially important as a social responsibility. According to the resource constraints, only an efficient utilisation of health services can provide that purpose. This study aims to develop a quantitative assessment framework for radiology centres as a vital section in healthcare to translate the patients' requirements into service quality specifications. This would help to achieve quality improvement by emphasising the voice of customers.

A literature review is conducted to specify the service quality criteria and the patients' requirements related to healthcare and hospitals. Based on the experts' opinions, these criteria and requirements are later customised for the radiology centres. Moreover, the requirements are categorised into five dimensions of SERVQUAL. The interrelations between service elements are also determined through expert group consensus using Pearson correlation. Afterwards, by applying the QFD method, the relations between the requirements and criteria are explored. Additionally, a customer satisfaction survey is executed in Tehran public hospitals to prioritise these requirements and provide an importance-satisfaction analysis.

Based on the result of the case study, service elements are prioritised for improvement, and practical suggestions are provided using the Delphi technique for quality improvement. In addition, a cause-and-effect diagram is presented to highlight the improvement area and provide enhancement suggestions.

This study is the first empirical attempt to benefit from the VOC in evaluating and enhancing the quality of service delivered to radiology patients. In doing so, the study applies a hybrid approach of QFD and SERVQUAL as well as other tools to highlight the improvement area and provide enhancement suggestions. The findings can be readily used by the practitioners.

Porous medium has always been introduced as an environment for increasing heat transfer in cooling systems. However, increase in heat transfer and resolving pressure drop in the fluid flow have been focused on by researchers.The purpose of this paper is to study the effects of creating porous micro-channels inside porous macro-blocks to optimize system performance in channels.

To simulate flow field, a developed numerical code that solves Navier–Stokes equations by finite volume method and semi-implicit method for pressure linked equations (SIMPLE) algorithm will be used together with bi-disperse porous medium (BDPM) method. Working fluid is air with Pr = 0.7 in laminar state. Influence of permeability changes by creation of micro-channels containing porous medium in vertical, horizontal and cross-shape patterns will be investigated.

By creating porous micro-channels inside macro-blocks, not only does the heat transfer increase significantly but the pressure also drops remarkably. Increase in performance evaluation criteria (PEC) is more evident in lower Reynolds numbers that can increase the PEC to 75 per cent by creating cross-shape micro-channels. By changing the permeability of micro-channels, PEC will increase by reducing the pressure drop but it has minor changes in Nu.

The current work is applicable to optimizing system performance by decreasing the pressure drop and increasing the heat transfer.

The developed patterns are useful in increasing the system performance including the increase in heat transfer and decrease in pressure drop in systems such as air coolers required in electrical circuits.

Development and optimization of system performance by new patterns using BDPM in comparison to the previous patterns.