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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Iranian Economic Review
- نوع مقاله: Journal Article
- کلمات کلیدی: C13,Keywords: Education Economics,Higher Education and Training,Global Competitiveness,Business sophistication,Canonical Correlation Analysis. JEL Classification: I25,I23,F00,M19
- چکیده:
- چکیده انگلیسی: Economics of education which investigates economic issues related to education - presents a framework which leads to better schedules and policy-making. On the other hand, the concept of competitiveness has drawn increasing attention of both scholars and governors in the past decade. The World Economic Forum (WEF) has published Global Competitiveness Index (GCI) in order to measure national competitiveness. The purpose of this paper is to investigate the interaction between the two sets of ‘Higher Education and Training’ (One of the pillars of GCI) and ‘Business sophistication’ both of which have been addressed by education of economics and not been profoundly investigated. To achieve the research aims, a descriptive correlational study has been used. The sample is 144 countries whose data were included in 2014-2015 report. Moreover, a canonical correlation analysis (CCA) has been employed to investigate the interaction between two sets of ‘Higher education and training’ and ‘Business sophistication’. The findings of the research revealed that a significant and positive relationship between two sets and more than 77.85% of changes in ‘Business sophistication’ can be predicted by changes in ‘Higher education and training’. In ‘Higher education and training’ sub-indexes ‘Local availability of research and training services’, ‘Extent of staff training’, ‘Internet access in schools’, and ‘Quality of management schools’ had the highest effect in creating this relationship.
- انتشار مقاله: 21-01-1395
- نویسندگان: Abbas Bazargan,Rohollah Ghasemi,Mohammad Eftekhar Ardebili,Mohammad Zarei
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Economic Review
- نوع مقاله: Journal Article
- کلمات کلیدی: Banking industry,Iranian Economy,Financial Sector,Mergers and Acquisitions (M&A),government policy and regulation,middle-east
- چکیده:
- چکیده انگلیسی: M any Middle-East countries, like Iran, have dynamic banking industries and have observed merger and acquisitions (M&A) waves. M&A waves are usually defined in the developed world context and some of their main drivers were identified as: market timing, environment's shocks, merger manias, government regulation and regulatory, and technological changes. It has been discussed that merger waves and their reasons are among the ten most important unsolved mysteries in the field of finance (Brealey and Myers, 1991, p. 923), and as a result of this, it was not possible to completely clarify the reasons behind emerging M&A waves, especially in developing countries; for this reason in these countries, there is a different story. In the past thirty years, the Iranian banking industry witnessed two waves of M&A. The later one commenced in 2011 and is still in progress. This study investigates the reasons behind emerging M&A waves in the industry by using the Exploratory Factor Analysis (EFA). The data for this study were collected from 113 bank managers. The results show that Iranian banking industry M&A wave is driven by three main forces/factors: macro, industrial, and corporate, which come from: I) Develop the business and acquire competitive advantage, II) Stakeholders’ pressures, III) Government pressure, IV) Lack of banking licenses, and V) Organize the money market by government.
- انتشار مقاله: 22-01-1393
- نویسندگان: Mohammad Zarei,Amir Alambeigi,Parveneh Karimi,Behrouz Zarei
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Mining and Geo-Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Simulation,Dynamic,Integrated,SIMULINK,mineral processing
- چکیده:
- چکیده انگلیسی: Operational variables of a mineral processing circuit are subjected to different variations. Steady-state
simulation of processes provides an estimate of their ideal stable performance whereas their dynamic
simulation predicts the effects of the variations on the processes or their subsequent processes. In this
paper, a dynamic simulator containing some of the major equipment of mineral processing circuits
(i.e. ball mill, cone crusher, screen, hydrocyclone, mechanical flotation cell, tank leaching and
conveyor belt) was developed. The dynamic simulator of each mentioned unit was also developed
according to population balance models with the help of MATLAB/Simulink environment and was
verified against the data from the literature. Comminution and separation sections were linked using
empirical models which correlate the separation and extraction kinetics to particle size. Applying the
developed simulator, the dynamic behavior of a grinding-leaching circuit was analyzed and the results
showed that such simulations are required for both designing and controlling the circuits.- انتشار مقاله: 25-01-1394
- نویسندگان: Fatemeh Khoshnam,Mohammad Reza Khalesi,Ahmad Khodadadi Darban,Mohammad Javad Zarei
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Nano Dimension
- نوع مقاله: Journal Article
- کلمات کلیدی: Nanofluid,Thermal conductivity,Triethylene Glycol,CuO Nanoparticle,Dehydration
- چکیده:
- چکیده انگلیسی: Liquid desiccants such as glycols are used in dehydration process, among which Triethylene Glycol (TEG) is considered as a common choice. The addition of nanoparticles to TEG as the base fluid is one of the prevalent method to improve thermal properties of TEG. In this study, an experimental investigation was performed on thermal conductivity of TEG-based nanofluids with 20 and 40 nm diameter copper oxide (CuO) nanoparticles analyzed at different conditions. Thermal conductivity was measured using a Decagon thermal analyzer (KD2 Pro Model) in the 20 °C-60 °C temperature range, and also 0.1- 0.9 wt.% range. The experimental results showed that thermal conductivity of the nanofluid enhances with temperature increasing. In addition, thermal conductivity of nanofluids increased with nanoparticle concentration in both cases of 20 and 40 nm nanoparticles. The highest enhancement was also ~ 13.5%, for the nanofluid with 20 nm nanoparticles at 60 °C and a 0.9 wt.% concentration.
- انتشار مقاله: 04-03-1398
- نویسندگان: Mohammad Javad Zarei,Peyman Keshavarz,Mohammad Mahdi Zerafat,Samad Sabbaghi
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Smart Electrical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Frequency estimation,disturbance,Phase-Locked Loop (PLL),Amplitude Estimation,Second-Order Generalized Integrator (SOGI),DC-offset
- چکیده:
- چکیده انگلیسی: This paper proposes a new method for parameter estimation of distorted single phase signals, through an improved demodulation-based phase tracking incorporated with a frequency adaptation mechanism. The simulation results demonstrate the superiority of the proposed method compared to the conventional SOGI (Second-Order Generalized Integrator)-based approach, in spite of the dc-offset and harmonic distortions.
- انتشار مقاله: 11-11-1394
- نویسندگان: Mohammad Zarei,Mohammad Karimadini,Mohsen Nadjafi,Abolfazl Salami
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Advanced Biological and Biomedical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: methanol extract,Tyrosinase,Inhibitor,A.siliquosus,V.phoeniceum
- چکیده:
- چکیده انگلیسی: Background:
Melanogenesis begins with the oxidation of L-tyrosine to L-Dopa by tyrosinase. Inhibition of tyrosinase could be effective in treatment of complications such as skin lesions, eczema and melasma. Inhibition of tyrosinase could be effective in treatment of those complications. The aim of this study was to determine inhibitory activity on tyrosinase and antioxidant activity of Astragalus siliquosus Bioss. and Verbascum phoeniceum L.
Methods:
Methanol extracts of organs of the plants were prepared by maceration. Inhibitory effects of the extracts were evaluated in 96 wells at 492 nm wavelength. The antioxidant activity of the extracts was evaluated using DPPH free radical scavenging index and iron reduction test.
Results;
For A.siliquosus, maximum inhibitory activity was of its flower extract (97% inhibition and IC50=1.58 mg/ml) and of its stem extract (100 % and IC50=2.1 mg/ml). For V.phoeniceum, the highest inhibitory activity was of its leaf extract (87% inhibition and IC50=3.2 mg/ml). Flower extract of A.siliquosus showed mixed Uncompetitive-Non-competitive pattern of inhibitory activity, while the extract of the V.phoeniceum leaf showed mixed Competitive-Non-competitive inhibitory pattern. All aerial parts of the A.siliquosus had 100% antioxidant activity with EC50s of 0.089, 1.78, 1.25 mg/ml for its flower, leaf and stem respectively. Leaves of the V.phoeniceum had a 100% antioxidant activity, with EC50 of 0.013 mg/ml.
Conclusions:
Methanol extracts of flower and leaf organs of A.siliquosus, and leaf organ of V.phoeniceum, had a reasonable inhibitory effect on tyrosinase activity. Feature studies could be focused on those organs to separate potential agents with pharmaceutical and cosmetic applications.- انتشار مقاله: 14-07-1398
- نویسندگان: Mohammad Ali Zarei,Masoumeh Babaei
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Advanced Biological and Biomedical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: diabetes,Alpha-glucosidase,Ferula haussknechtii,Haplophyllum acutifolium,Enzymatic inhibition
- چکیده:
- چکیده انگلیسی: Background:
α-Glucosidase Inhibition can significantly prevent glucose uptake after meal, and helps in controlling of some adverse effects in diabetics. So determination of α-Glucosidase inhibitory effect and antioxidant activity of the Haplophyllum acutifolium and Ferula haussknechtii aerial organs was the aim of this study.
Methods:
Inhibitory effect of hexane extracts from different organs was investigated in several concentrations at 405 nm wavelength using a microplate reader. Antioxidant activity of hexane extracts of various organs was also measured using DPPH and iron reduction tests.
Results;
The highest inhibitory activity of F.haussknechtii was observed at the 0.1 g/ml concentration of flower extract (100% inhibition and IC50= 0.1 μg /ml) and the most inhibitory activity of H.acutifolium, was related to the 1 g/ml concentration of flower extract (100% inhibition and IC50 = 10 μg /ml) and leaf extract (100% inhibition and IC50 = 60 μg /ml). Extract of H.acutifolium flower and leaves showed Non-competitive inhibition pattern and F.haussknechtii flower showed mixed (Competitive -Non-Competitive) inhibitory pattern at 0.001 g/ml and exhibit uncompetitive inhibitory pattern at the 0.1 g/ml. The results of antioxidant potential showed EC50 for F.haussknechtii flower and H.acutifolium leaves equalled 2.37 and 0.96 mg/ml, respectively.
Conclusions:
The hexane extract of the F.haussknechtii flower, and H.acutifolium flower and leaf organ have a significant inhibitory effect on the activity of α-Glucosidase, DPPH free radical scavenging activities and reducing power. So they are good resources for extraction of medicinal compounds to control blood level of glucose after meal, in diabetic patients.- انتشار مقاله: 17-05-1398
- نویسندگان: Mohammad Zarei,Hero Ghafaryan
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Advanced Biological and Biomedical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: diabetes,Alpha-glucosidase,Ferula haussknechtii,Haplophyllum acutifolium,Enzymatic inhibition
- چکیده:
- چکیده انگلیسی: Background:
α-Glucosidase Inhibition can significantly prevent glucose uptake after meal, and helps in controlling of some adverse effects in diabetics. So determination of α-Glucosidase inhibitory effect and antioxidant activity of the Haplophyllum acutifolium and Ferula haussknechtii aerial organs was the aim of this study.
Methods:
Inhibitory effect of hexane extracts from different organs was investigated in several concentrations at 405 nm wavelength using a microplate reader. Antioxidant activity of hexane extracts of various organs was also measured using DPPH and iron reduction tests.
Results;
The highest inhibitory activity of F.haussknechtii was observed at the 0.1 g/ml concentration of flower extract (100% inhibition and IC50= 0.1 μg /ml) and the most inhibitory activity of H.acutifolium, was related to the 1 g/ml concentration of flower extract (100% inhibition and IC50 = 10 μg /ml) and leaf extract (100% inhibition and IC50 = 60 μg /ml). Extract of H.acutifolium flower and leaves showed Non-competitive inhibition pattern and F.haussknechtii flower showed mixed (Competitive -Non-Competitive) inhibitory pattern at 0.001 g/ml and exhibit uncompetitive inhibitory pattern at the 0.1 g/ml. The results of antioxidant potential showed EC50 for F.haussknechtii flower and H.acutifolium leaves equalled 2.37 and 0.96 mg/ml, respectively.
Conclusions:
The hexane extract of the F.haussknechtii flower, and H.acutifolium flower and leaf organ have a significant inhibitory effect on the activity of α-Glucosidase, DPPH free radical scavenging activities and reducing power. So they are good resources for extraction of medicinal compounds to control blood level of glucose after meal, in diabetic patients.- انتشار مقاله: 17-05-1398
- نویسندگان: Mohammad Zarei,Hero Ghafaryan
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Advanced Biological and Biomedical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Plant extract,Diabetes Mellitus,Alpha-glucosidase,Inhibitor,Hexane
- چکیده:
- چکیده انگلیسی: Objective: Alpha-glucosidase, as a carbohydratase catalyses the liberation of alpha-glucose from the nonreducing end of some carbohydrates from foods in digestive tract. Consequently, retard absorption of glucose by the inhibition of carbohydrate hydrolyzing enzymes is one of the therapeutic approaches to decrease the postprandial hyperglycemia. Recently, a great deal of attention has been paid to natural products like plants, as a reliable source for bioactive compounds.The aim of this study was to find new potent inhibitors for Alpha-glucosidase among plant extracts. Methods: Hexan extracts of 60 plants species were screened for their Alpha-glucosidase inhibitory activity at 0.001, 0.01, 0.1 and 1 mg/mL concentration. Acarbose, dissolved in buffer, was used as a positive control. Every experiment was done in triplicate.Descurania Sophia (L.) Webb & Berth, Fumaria vailantii Loisel, Ferula Haussknechti Wolf ex Rech,Haplophyllum acutifolium (DC.)G.Don, Isatis cappadociaca Desv., Eremostachys laevigata Bunge, Silene aucheriana Boiss exhibited more than 60% alpha-glucosidase inhibitory activity.. Results: Among them, Descurania Sophia, Fumaria vailantii and Ferula haussknechti exhibited significant alpha glucosidase inhibitory activity with IC50 values of 0.9 µg/ml, 24.55 µg/ml and 2.71 µg/ml, respectively. Because of its high inhibitory activity and low IC50, Descurania Sophia extract would be interesting for further studies
- انتشار مقاله: 20-06-1394
- نویسندگان: Mohammad Ali Zarei,Mina Poursharifi
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Advanced Biological and Biomedical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Inhibition,Tyrosinase,Hexane extract,Gundelia,Tourneforti L
- چکیده:
- چکیده انگلیسی: Objective: Tyrosinase as the key enzyme in melanin biosynthesis, involves in determining the color of mammalian skin and hair. A variety of dermatological disorders, come up from an unnecessary level of epidermal pigmentation. Plants are low-cost and rich sources of active compounds. Methods: More than seventy native plants collected from the central region of Kurdistan province collected. Inhibitory effect of hexane extracts from aerial parts of them was tested on tyrosinase activity. All extracts were screened for their tyrosinase inhibitory activity at 1, 0.1, 0.01, 0.001 µg/ml concentrations. Assay method was based on Microplate spectrophotometric study of absorption in 492 nm, arbutin and kojic acid were used as positive controls. Results: Among the evaluated hexane extracts, only 10 cases showed more than 50% tyrosinase inhibitory activities, including Gundelia Tourneforti L., Astragalus vegetus Bunge, Vicia hyrcanica Fisch. & C.A. Mey, Campanula involucrate Auch.ex DC, Isatis cappadocica Desv, Sanguisorba minor Scop., Eremostachys laevigata Bunge, Ballota nigra L., Aristolochia bottae Jaub.&Spach, Astragalus caryolobus Bge, and among them Gundelia Tournefortii L. L., showed considerable inhibition with IC50 of 0.173 µg/ml. These results suggest that the most effective plant extracts, especially that of Gundelia Tourneforti L. be worthy of further investigation.
- انتشار مقاله: 01-10-1393
- نویسندگان: Farideh Hashemi,Mohammad Ali Zarei
- مشاهده