Showing 15 results for Ardekani
Volume 1, Issue 1 (2-2016)
Abstract
Background: we aimed to evaluate the effect of body weight and Body Mass Index (BMI) on Bone Mineral Density (BMD) in healthy postmenopausal Iranian women. Material and Methods: Two hundred postmenopausal women (age between 51 and 69 years) who had presented to the nuclear medicine center at Shariati Hospital in Tehran, Iran between April 2012 and August 2013 were included in this cross sectional study. Of these 46 healthy women who met the study criteria constituted for evaluation. After recording weight and height of individuals, Body Mass Index (BMI) (kg/m2) was calculated as weight (kg) divided by height square (m2). Bone Mineral Density (BMD) in Femoral Neck (FN) and lumbar spine sites (L1-L4) were measured by dual-energy X-ray absorptiometry (DEXA). Results: We observed statistically significant negative correlation between BMD measurements at femoral neck and lumbar1-4 spine with age and significant positive correlation with weight and BMI. Stepwise multiple linear regression analysis showed that only weight and age, after adjustments to BMI determined lumbar1-4 spine BMD (R² = 23%) and femoral neck BMD (R² = 28.6%). Conclusions: These results suggest that the relationship between body weights and BMD is Stronger than the relationship between BMI and BMD. Therefore, in comparison with body mass index, body weight alone is a better predictor of bone mineral density.
Volume 7, Issue 1 (5-2015)
Abstract
Since the formation of absolutist state by King Reza in Iran, there are so many approaches about how it has formed. There are, generally, two main approaches that stand against each other. One approach is monarchism, and its advocates, by following Marcs Weber, believe that King Reza’s absolutism state can be considered as monarchism, and choose an elitism approach. In contrast, some people insist on structural factors. In their opinion, structures play an important role in absolutism state formation and the agent (King Reza) cannot be so important. In this study, Gidenz structuration approach has been adopted that might be a medium approach; we tried to investigate the reciprocal role of structure and agent. Structuration is a method that concentrates on both the agent’s role in context, and cooperative and reciprocal transaction between structure and agent. With these considerations, the present article has been organized around two central questions: How to make and adopt an intermediate approach: and How the absolutist state was formed?
Volume 8, Issue 2 (10-2016)
Abstract
This article analyzes the rate of electoral participation during ten periods of presidential election in Iran within 1979-2009. The rate of electoral participation in Iran’s presidential elections has been problematic and not based on a regular pattern of change. Having proved this claim, the theory of democratic political system was chosen as the theoretical foundation of the paper in order to find a solution to the problem. The problem was related logically to the theory and inspired by the theory, the research question was formulated. On the theoretical level, it was argued that there is a relationship between party competition and electoral participation such that by an increase in the extent of party competition, the electoral participation will also increase. This argument was put through a regression analysis. Available evidence indicates that there exists a 45% positive correlation between electoral participation and party competition.
M. A. Ardekani, P. Asghari Tehrani,
Volume 10, Issue 3 (12-2010)
Abstract
Hot wire Anemometer (CTA) can be used to measure instantaneous flow velocity with high frequency. Since the principle of opearation of CTA is based on convective cooling, determination of the air flow direction is difficult. In this Research paper, we have used two cylindrical hot-film sensors placed in parallel to determine the flow direction. The wake effect and the heat due to the upstream sensor on the downstream sensor has been used to identity the flow direction. Effect of wake and presence of the upstream sensor on the downstream sensor has been studied. The results have been used to construct a probe consisting of two parallel sensors, sepereated by 1mm distance. Performance of the probe has been evaluated at various flow angles for laminar and turbulant flows. Findings of this study show that this probe provides the best performance at ±10 flow angles.
Volume 12, Issue 49 (10-2015)
Abstract
This study investigates the effect of olive oil on the caseinate‐based films. Edible films based on caseinate (5% (w/v)) and glycerol (30% (w/w)) by varying olive oil concentrations (0, 10, 20 and 30% (w/w), were prepared by casting method films. The impact of the incorporation of olive oil into the film matrix was studied by investigating the physical and mechanical properties of films. Scanning electron microscopy (SEM) was also used in order to analyse films microstructure. Increasing the olive oil concentrationup to30%(w/w) decreased values for thickness and solubility from 0.050mm and 92.18% to 0.042mm and 61.84% respectively and caused the films to become opaque. Also addition of olive oil to caseinate emulsion significantly improved the WVP (upto9×10-10g/s.m.pa)of prepared films, but lowered the mechanical properties. The results indicate that the structure and properties of caseinate edible films were modified and improved by the olive oil.
Hajar Hassani-Ardekani, Hanieh Niroomand Oscuii,
Volume 16, Issue 6 (8-2016)
Abstract
Molecular Dynamics (MD) method is a computer simulation for studying the physical movements of atoms and molecules of a N-body system by solving classical equations of motion. Here, this method is used to investigate the structural changes of a vital molecular bond in the body. This bond is created by the interaction of P-selectin, expressed on activated endothelium, and its counterpart P-selectin glycoprotein ligand-1 (PSGL-1) which is expressed on leukocytes. Frequent association and dissociation of these bonds allow the leukocyte to roll on the endothelium layer which is a pivotal step in inflammatory responses. Understanding the mechanism underlying the dissociation process of this bond is helpful in pathological researches. Here this process is simulated with MD method using the program NAMD and Visual Molecular Dynamics (VMD). The results indicate that the hydrogen bonds between ion Ca2+ and residue fucose of glycan group of PSGL-1 and also between sulfated tyrosine residues are the most effective bonds in binding.
Volume 16, Issue 87 (5-2019)
Abstract
Biodegradable edible coatings, their enrichment with essential oils and their use on the surface of fruits are influential approaches that can reduce the problems of post-harvest management, thereby maintaining the quality of the produce. In this study, different concentrations of Arabic gum (0, 6 and 8% w/v) were used in combination with different concentrations of Shirazi thyme essential oil (0, 0.3 and 0.5% w/v), and their effects were measured with respect to various qualitative characteristics of fresh pistachio nuts which were evaluated for a period of 36 days under conditions of storage at a temperature of 3 ± 1°C. The results showed that the growth of mold and yeast and the growth of aerobic bacteria on the samples were significantly less than in other samples when using the 6% Arabic gum concentration enriched with the essential oil of Shirazi thyme at 0.3 and 0.5%. Also, adding the essential oil of Shirazi thyme (at 0.3 and 0.5%) to the formulation of Arabic gum (6%) managed to reduce the occurrence of water loss from the fresh pistacia and significantly reduced the weight loss from the samples. The addition of essential oil to the Arabic gum coating contributed significantly to the preservation of carbohydrates, chlorophylls, phenolic compounds, and antioxidants in the kernels of the fresh pistachios. Therefore, the use of edible coatings of 6% Arabic gum containing Shirazi thyme essential oil (at 0.3 and 0.5%) can maintain the quality and increase the shelf life of fresh pistachio.
Volume 16, Issue 87 (5-2019)
Abstract
Date fruit (Phoenix dactylifera L.) is a rich source of sugar, fiber, some vitamins, minerals and antioxidant phenolic compounds. The physico-chemical, biochemical and microbial changes occurring in this fruit reduce its quality properties during storage time. In the present study, the effects of polyethylene film containing 1 and 2% zinc oxide nanoparticles as nanocomposite packaging and film without nanoparticles as a control were evaluated in order to maintain some quality characteristics of Mazafati date fruit in two storage temperatures of 4 and 25 °C for 120 days. The results of analysis of variance showed that the effects of nanocomposite film, temperature and storage time on the studied parameters of Mazafati date were significant (p <0.05). The least changes in quality parameters of weight loss, pH, titratable acidity, total soluble solids, total phenolic content and total and reducing sugar contents were observed in date samples packed in 2% nanocomposite film stored at 4 °C. The change in control sample stored at 25 °C was significantly higher than other samples. In addition, the use of nanocomposite packaging reduced the microbial growth rate (total aerobic mesophilic bacteria, and mold and yeast) compared to the control sample. With increasing storage temperature from 4 to 25 °C, an increasing trend was observed in microbial growth and changes in the quality parameters of all samples, which indicated a decrease in the quality characteristics of the date fruit. Considering the studied parameters, nanocomposite packaging containing 2% zinc oxide had better performance than nanocomposite packaging containing 1% zinc oxide. In general, the use of nanocomposite film containing 2% zinc oxide nanoparticles is suggested to maintain the quality characteristics of Mazatifi dates at a temperature of 4 °C.
Volume 17, Issue 6 (11-2015)
Abstract
Pistachio nut (Pistacia vera L.) is one of the most delicious and nutritious nuts in the world. In order to increase the added value of the pistachio nuts, it is necessary to develop new products to meet consumer needs. This is the first paper on pistachio halva. The product was developed using pistachio paste (as main ingredient), mixture of sugar-glucose, egg white and citric acid. The effect of soapwort root extract (from saponaria officinalis) and Glycyrrhizin (from Glycyrrhiza glabra) as whitening and emulsifying agent in three levels (0.00, 0.10, and 0.15%) on the oil separation, consumer acceptance, and texture of pistachio halva was investigated. Sensory evaluation was carried out after 4 months storage at 20±2°C. There was a significant difference (P< 0.05) between samples with and without soapwort and glycyrrhizin. The oil separation (R= 0.595, P=0.001), from halva were moderately correlated to the hardness. The sensory texture of halva was negatively correlated to the hardness (R= -0.694, P= 0.000) and oil separation (R= -0.730, P= 0.000). The sensory color (R= 0.652, P= 0.000) of halva was moderately correlated to the a-value. It is recommended that mixture of 0.10% soapwort root extract and 0.10% commercial Glycyrrhizin be used for the pistachio halva production. Using combination of soapwort root extract and Glycyrrhizin in the formulation of pistachio halva prevents oil separation from the product and increases its consumer acceptance. Development of pistachio halva would potentially increase the food uses of nuts and introduce consumers with a healthier non-animal snack food.
Saeed Farsad, Mohammed Ali Ardekani, Foad Farhani,
Volume 18, Issue 4 (8-2018)
Abstract
measurement accuracy. The angular response of the sensor describes the relationship between flow velocity vector and heat transfer from the sensor, which is determined by a sensitivity function. In this paper, two sensitivity functions, namely cosine law and Hinze equation, have been studied using wind tunnel experiments to evaluate the effect of various parameters such as flow conditions (velocity and direction), probe aspect ratio (l/d) and probe operational condition (sensor temperature) on the range of applicability of cosine law and magnitude of the sensitivity coefficient, k. Results show that the angular range of applicability of cosine law depends on flow and probe conditions. At 1% measurement error, the range of applicability of cosine law for flow measurements of velocities exceeding 10 m/s was found to be in the range of ±30º. Moreover, at geometrical ratios higher than 600, two-dimensional flow measurements using the cosine law presents results with acceptable accuracy. In addition, the sensitivity coefficient is completely dependent on flow condition and probe aspect ratio, and its value decreases with increase in flow angle and velocity and reduction in probe aspect ratio. The results of this research can be used in the selection and proper design of probes for two-dimensional flow measurements using hot wire anemometers.
Volume 19, Issue 1 (1-2017)
Abstract
Pistachio nut (Pistacia vera L.) is one of the popular and nutritious tree nuts in the world. Pistachio spread is a new product which is made from pistachio paste, icing sugar, Soy Protein Isolate (SPI), and Red Palm Oil (RPO). This study involved sensory acceptability (by 32 assessors) using Hedonic scale and development of suitable terminology for describing pistachio spread using Quantitative Descriptive Analysis (QDA). This study represents the first report on using QDA for sensory evaluation of pistachio products. The QDA method is used to determine the sensory profile of the two pistachio spreads with higher acceptability in the Hedonic scale (Formulation 12 including 50% pistachio paste, 30% icing sugar, and 20% RPO and Formulation 16 including 58.3% pistachio paste, 25% icing sugar, and 16.7% RPO). According to the results, RPO has a direct effect on the sensory acceptance of pistachio spread (P< 0.05). Eight panelists were selected for evaluation of pistachio spread. Twenty attributes (in terms of appearance (green color, visible particles, glossy), aroma (sweet, roasted, nutty, milky/creamy), flavor taste (beany, sweet, oily, bitter, nutty, creamy), texture (stickiness, oiliness, firmness, adhesiveness, spreadability), and aftertaste (bitter, astringency) were identified and developed for the product. No significant difference was observed in all pistachio spread formulations attributes, except for sweetness (P< 0.05).
S. Farsad, M.a. Ardekani, Foad Farhani,
Volume 19, Issue 5 (May 2019)
Abstract
In two-dimensional measurements using hot wire anemometer, the sensitivity of the sensor to change the flow direction of direction or of of particular importance.
flow velocity vector and heat transfer from the hot wire sensor is determined, using the Yaw sensitivity function and its coefficient. In some cases, negative values of Yaw sensitivity coefficient
are encountered, for which no specific reason has been presented. In this paper, reason of negative values of
for un-plated sensors of hot wire anemometer in two-dimensional measurements have been investigated experimentally. For this purpose, flow velocity field between the prongs of a model of a normal probe (SN) at different velocities and Yaw angles have been studied. Results show that the probe’s prongs produce flow disturbances, which cause a reduction in flow velocity and the deviation (rotation) of the flow adjacent to the prongs and the sensor. At different Yaw angles, the maximum reduction in flow velocity amounts to 3% and the deviation of flow direction has a maximum of 6.3°. It is supposed that this phenomenon affects the amount of heat transfer from the sensor and the effective velocity obtained by the hot wire anemometer, which eventually produces the reported negative
values.
Volume 20, Issue 3 (Fall 2016)
Abstract
The human need to energy is increasing constantly and fossil energy sources is decreasing. The indiscriminate use of fossil fuels pollute the environment and threaten life on Earth. Today in addition to modifying consumption, use of renewable energy is one of the ways to solve the energy crisis. The Solar energy is one of the renewable energies. In this study the application of GIS in the Assessment of using solar energy to supply lighting systems of Highway Zanjan - Tabriz by function of Solar Analyst has been studied. In this article, the DEM ASTER satellite’s data of the study area in the Arc GIS software were used to calculate the solar radiation reaching the Earth's surface for six months (May and October).The results of this investigation showed that the study area due to variation of topography has different surface radiation and confirmed the possibility of using solar photovoltaic systems to supply lighting systems of Highway Zanjan - Tabriz. In the matter of the most important factor which affects the received radiation to surface, function of Solar Analyst has the most correlation with the height and the lowest correlation with the slope aspect.
Volume 23, Issue 1 (1-2021)
Abstract
The combined coating-effects of Sodium Alginate (SA) and Thyme Essential Oil (TEO) was investigated at three levels of, respectively, (0.0, 1.0, and 1.5 %) and (0.0, 0.3, and 0.5%) on fresh pistachio during 6 weeks of cold (3±1°C) storage. Physiochemical parameters (hull and hard-shell color, hull hardness, soluble sugar, chlorophyll, and soluble solids content) and microbial load (plate count agar) were measured every 2 weeks of storage. Similarly, the sensory attributes of pistachio
were evaluated by trained panelists and Quantitative Descriptive Analysis (QDA) method from minimum (1) to maximum level (15) score. While weight loss of each pistachio sample increased during storage time, those treated with alginate had considerably less weight losses than other treatments. The pistachio treated with combination of
SA (1%) and TEO(0.3 or 0.5%) showed significantly higher hull hardness, L* values, soluble sugar, chlorophyll, and lower growth of microorganisms (mainly yeast and mold) than other treated and non-treated (control) samples. The highest sensory scores of 12.3 and 10.6 for hull color of pistachio were related to samples coated again with combinations of
SA (1%) and TEO (0.3 or 0.5%), respectively, and were significantly higher than the score of control sample (6.4). Since the pistachio treated with the above-mentioned concentrations of SA and TEO had significantly higher physiochemical, microbiological, and sensory attributes than the other samples, their quality indicators were superior to other treatments (including control samples) and, most probably, they had longer shelf lives and potential to preserve their natural characteristics of fresh pistachio during storage.
Ehsan Ardekani, Mohammad Ali Ardekani, Foad Farhani,
Volume 25, Issue 1 (January 2024)
Abstract
One of the methods to improve the performance of the vortex flowmeter, especially for low flowrate, is to use a dual bluff model that increases the vortex shedding frequency. In this experimental research work, the vortex shedding from a dual cylindrical bluff model of semicircular cross-section, at different l d ratios, where d is the diameter and l is the distance between the two semicircular cylinders in series is measured and investigated using a wind tunnel and hot-wire anemometer. Results show that the Strouhal number for dual bluff body depends on the Reynolds number and l d . In the range of 0/8≤ l d <2 , the Strouhal number has changes and jumps compared to the Reynolds number. Therefore, it is not suitable for vortex flowmeter application. also show that the velocity frequency spectrum, it can be determined that the highest value of the turbulent intensity is related to the oscillating velocity with the vortex shedding frequency, and therefore, to investigate the strength of vortex shedding frequency, the turbulent intensity was investigated, that the value of turbulent intensity depends on Reynolds number and l d . Considering the standard deviation of the repeatability of the Strouhal number reading and also the strength of the vortex shedding frequency (investigation of the turbulent intensity), for 0< l d <0/8 and 2≤ l d ≤3 , a dual cylindrical bluff model of semicircular cross-section, placed in series, is suitable for vortex flowmeter application
