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Volume 0, Issue 0 (Articles accepted for Publication 2024)
Abstract
Aim and Introduction
One of the most important issues in Iran's economy is related to managing the exchange rate, inflation and budget deficit. During tightening of the sanctions, the oil revenues are limited which potentially leads to an increase in the budget deficit as well as a decrease in the currency supply which accelerates the exchange rate. On the other hand, with the increase in the budget deficit, the probability of borrowing from the banking system and also the issuance of bonds increases, which in turn rise the monetary base and liquidity. In addition, inflationary expectations also increase, which can be effective in improving assets prices. With an increase in inflation, based on the inflation-currency spiral, there is a possibility of a grow in exchange rate in order to maintain the competitiveness of domestic production. This can accelerate the price of imported commodities and cause domestic inflation again. With the increase in inflation and households spending, nominal wages will have a higher growth compared to normal conditions in order to maintain minimum purchasing power, which can again face the government with limited resources and more borrowing to meet current expenses. From the monetarists’ point of view and the classical economics, in general, the main stimulator in increasing inflation is the growth of money and liquidity. However, from the post-Keynesian economists’ point of view, inflation increases the demand of money and subsequently liquidity. On the other hand, with an increase in the exchange rate, the government's expenses usually increase more than its income, which can lead to an increase in the government's budget deficit. Also, considering the existence of a monopoly in currency supply by the central bank, the hypothesis of using currency exchange revenues (the difference between free and budget-approved currency) will be applicable and this issue can raise the impact of the budget deficit on the exchange rate. Therefore, there has always been a serious challenge among economists as well as macroeconomic decision-makers about the connectedness between macroeconomic variables. What is the main driver of the network between macro variables? Is there a different way of communication in different thresholds of their growth rate? These cases show that it is very important to examine the time-varying interrelationships between these macroeconomic variables.
Accordingly, there is a complex connection between exchange rate, inflation, budget deficit and liquidity, which can be varied in different years. Therefore, in this research, using the TVP-TVAR technique, the time-varying connectedness across exchange rate, inflation, budget deficit and liquidity is examined during March, 2006 to August, 2023.
Methodology
In the current research, the relationship between exchange rate fluctuations, inflation, government budget deficit and liquidity based on monthly data using the TVP-TVAR technique is investigated. It should be noted that all the required information is extracted from the economic indicators of the central bank, and the government's budget deficit data from 2017 onward are extracted from Iran's Program and Budget Organization.
Findings
The results show that exchange rate and liquidity are, respectively, the largest net transmitter of volatilities in the network. Moreover, inflation rate and government budget deficit, respectively, are the largest net receivers of shocks from network. On average, the TCI is 23%, and more than 70% of this interrelationship between variables is explained by other factors such as political ones. Moreover, if the variables underestimated grow up to 36% annually (3% monthly), the connection between them will be cut off. In the conditions of decreasing the growth rate of variables up to -3% per month, the exchange rate has played a dominant role and its volatilities are transferred more strongly to inflation rate and less strongly to the budget deficit and liquidity.
If the growth rate of the variables is up to 24% annually (threshold of +2% monthly growth rate), the exchange rate volatilities are transferred to inflation and no interconnectedness between other variables is observed.
Discussion and Conclusion
Our results show that, on average, the total connectedness index from 2012 to 2016 has been upward, which is caused by the tightening of sanctions and the increase in inflationary expectations, psychological factors and emotions. Moreover, the connectedness between them is increased in 2018 and 2019, which is related to the intensification of sanctions and the reduction of currency supply and the increase in inflation and budget deficit and subsequently the increase in the issuance of debt securities in the capital market in order to manage the budget deficit and as a result increase liquidity. The results show that exchange rate is a main net transmitter of volatilities in most years and the inflation rate is a main net receiver of volatilities in many years. From 2016 onwards, the budget deficit is the net receiver of shocks from network in most periods, except for one period in 2019. It is interesting to note that in 2019, with the increase in the budget deficit and the issuance of debt securities, the budget deficit is transmitter, liquidity is receiver and inflation is more receiver variable than liquidity in the network. Totally, the results show that exchange rate is the major net transmitter of shocks to other macro variables.
Moreover, based on the results of the sensitivity analysis and thresholds effect, if the growth rate of variables is up to 24% annually (threshold of +2% monthly growth rate), the exchange rate fluctuations will be transferred to inflation and no connection between other components is observed. This shows that the macroeconomic management of the economy is very sensitive to the growth rate of the thresholds of the macroeconomic components, and before the political economy and also the factors of expectations and emotions dominated the economy, the macroeconomic management, especially the exchange rate, is required. Otherwise, it is impossible to manage the investigated variables with monetary and fiscal policies. Therefore, the managed floating exchange rate should be taken into consideration and if the goal is to manage the network using macroeconomic theories, the variables should not be allowed to increase by more than 24% annual growth. Other factors such as the political economy, and especially inflationary expectations will get the dominant role in the economy
One of the most important issues in Iran's economy is related to managing the exchange rate, inflation and budget deficit. During tightening of the sanctions, the oil revenues are limited which potentially leads to an increase in the budget deficit as well as a decrease in the currency supply which accelerates the exchange rate. On the other hand, with the increase in the budget deficit, the probability of borrowing from the banking system and also the issuance of bonds increases, which in turn rise the monetary base and liquidity. In addition, inflationary expectations also increase, which can be effective in improving assets prices. With an increase in inflation, based on the inflation-currency spiral, there is a possibility of a grow in exchange rate in order to maintain the competitiveness of domestic production. This can accelerate the price of imported commodities and cause domestic inflation again. With the increase in inflation and households spending, nominal wages will have a higher growth compared to normal conditions in order to maintain minimum purchasing power, which can again face the government with limited resources and more borrowing to meet current expenses. From the monetarists’ point of view and the classical economics, in general, the main stimulator in increasing inflation is the growth of money and liquidity. However, from the post-Keynesian economists’ point of view, inflation increases the demand of money and subsequently liquidity. On the other hand, with an increase in the exchange rate, the government's expenses usually increase more than its income, which can lead to an increase in the government's budget deficit. Also, considering the existence of a monopoly in currency supply by the central bank, the hypothesis of using currency exchange revenues (the difference between free and budget-approved currency) will be applicable and this issue can raise the impact of the budget deficit on the exchange rate. Therefore, there has always been a serious challenge among economists as well as macroeconomic decision-makers about the connectedness between macroeconomic variables. What is the main driver of the network between macro variables? Is there a different way of communication in different thresholds of their growth rate? These cases show that it is very important to examine the time-varying interrelationships between these macroeconomic variables.
Accordingly, there is a complex connection between exchange rate, inflation, budget deficit and liquidity, which can be varied in different years. Therefore, in this research, using the TVP-TVAR technique, the time-varying connectedness across exchange rate, inflation, budget deficit and liquidity is examined during March, 2006 to August, 2023.
Methodology
In the current research, the relationship between exchange rate fluctuations, inflation, government budget deficit and liquidity based on monthly data using the TVP-TVAR technique is investigated. It should be noted that all the required information is extracted from the economic indicators of the central bank, and the government's budget deficit data from 2017 onward are extracted from Iran's Program and Budget Organization.
Findings
The results show that exchange rate and liquidity are, respectively, the largest net transmitter of volatilities in the network. Moreover, inflation rate and government budget deficit, respectively, are the largest net receivers of shocks from network. On average, the TCI is 23%, and more than 70% of this interrelationship between variables is explained by other factors such as political ones. Moreover, if the variables underestimated grow up to 36% annually (3% monthly), the connection between them will be cut off. In the conditions of decreasing the growth rate of variables up to -3% per month, the exchange rate has played a dominant role and its volatilities are transferred more strongly to inflation rate and less strongly to the budget deficit and liquidity.
If the growth rate of the variables is up to 24% annually (threshold of +2% monthly growth rate), the exchange rate volatilities are transferred to inflation and no interconnectedness between other variables is observed.
Discussion and Conclusion
Our results show that, on average, the total connectedness index from 2012 to 2016 has been upward, which is caused by the tightening of sanctions and the increase in inflationary expectations, psychological factors and emotions. Moreover, the connectedness between them is increased in 2018 and 2019, which is related to the intensification of sanctions and the reduction of currency supply and the increase in inflation and budget deficit and subsequently the increase in the issuance of debt securities in the capital market in order to manage the budget deficit and as a result increase liquidity. The results show that exchange rate is a main net transmitter of volatilities in most years and the inflation rate is a main net receiver of volatilities in many years. From 2016 onwards, the budget deficit is the net receiver of shocks from network in most periods, except for one period in 2019. It is interesting to note that in 2019, with the increase in the budget deficit and the issuance of debt securities, the budget deficit is transmitter, liquidity is receiver and inflation is more receiver variable than liquidity in the network. Totally, the results show that exchange rate is the major net transmitter of shocks to other macro variables.
Moreover, based on the results of the sensitivity analysis and thresholds effect, if the growth rate of variables is up to 24% annually (threshold of +2% monthly growth rate), the exchange rate fluctuations will be transferred to inflation and no connection between other components is observed. This shows that the macroeconomic management of the economy is very sensitive to the growth rate of the thresholds of the macroeconomic components, and before the political economy and also the factors of expectations and emotions dominated the economy, the macroeconomic management, especially the exchange rate, is required. Otherwise, it is impossible to manage the investigated variables with monetary and fiscal policies. Therefore, the managed floating exchange rate should be taken into consideration and if the goal is to manage the network using macroeconomic theories, the variables should not be allowed to increase by more than 24% annual growth. Other factors such as the political economy, and especially inflationary expectations will get the dominant role in the economy
Volume 0, Issue 0 (9-2025)
Abstract
Mayetiola destructor (Say, 1817) originated in the Fertile Crescent region of the Middle East and is one of the most serious pests of wheat, rye and barley and more than 16 Poaceae wild species. Here, we report the occurrence of this species as an invasive pest for the first time in Iran. It was detected in wheat fields and rye in Qüshchï Pass, Urmia environ, West Azarbaijan province (September 2020) as well as in wheat fields in Bil-e Savar, Ardabil province (July 2024). The diagnostic characters and its life history as well as the photographs of the adult male and female, larvae, puparium, male genitalia and wing venation are provided. This is the second species from the genus Mayetiola that has been reported from Iran. To prevent the spread of this destructive pest in Iran, suitable management practices are urgently needed.
Volume 0, Issue 1 (5-2011)
Abstract
Several models have been developed to estimate land degradation rate and evaluate desertification severity. This study attempts to apply the MEDALUS (Mediterranean Desertification and Land Use) model by considering existing conditions in the Hamoun wetland, located in south-eastern Iran. At first identification of the main factors affecting the desertification phenomenon was attempted, based on field survey. These factors include climate, soil, vegetation and management practices. Results showed that land management and extreme climate are the most important factors affecting the desertification process. In addition, in some land uses, lack of vegetation accelerates the prevalent wind intensity in the study area (known as “the 120Rozeh” (means 120 days and refers to the wind, with high speeds that blow from the North to the South during summer time) – the most famous Iranian winds) which continues its path without any barrier, and erodes the land surface. Results also indicated that the study area is mostly located in the critical desertification class. Based on the results, it is known that 14% of whole region (12,273 ha) is in the low-critical class, 48.2% (42,251 ha) in the medium-critical class, and 37.8% (33,134 ha) in the high-critical class.
Volume 0, Issue 2 (8-2011)
Abstract
Sediment-related environmental problems pose a serious threat to sustainable land management in many developing countries, including Iran. Information regarding sediment sources represents a key requirement from the management perspective since identification of sediment sources is a precursor to the design of effective sediment management and control strategies. The fingerprinting approach has increasingly been adopted as an alternative to assembling such information. A wide range of fingerprint properties has been used as a means of discriminating potential sediment sources. However, determining the ability of these properties is very important in the design of cost-effective catchment management strategies before each study. This contribution addresses the ability of two acid extractable metals (Co and Cr) that were used extensively in previous studies to be used to differentiate sediment sources. The results of the statistical analysis demonstrate that no single property is capable of classifying the source material samples into the correct source categories at the Amrovan drainage basins. In the case of the Atary drainage basin, Cr and Co were found in only 47.5 and 43.8% of the source material samples respectively. According to the result obtained, it is recommended that acid extractable metals for sediment sources differentiation in conjunction with the composite of other properties to improve sediment source discrimination.
Volume 1, Issue 1 (3-2013)
Abstract
Uncoated fish burgers were produced in order to expand the variety of products from Silver carp, Hypophthalmichthies molitrix ,and increase the consumption of this fish species. On the other hand in order to compare the effect of ascorbic acid and vacuum packaging on rancidity inhibition and microbial quality, 3 different treatments of fish burger were produced: 1. Burger with common packaging (Control group), 2. Burger with vacuum packaging 3. Burger with 500 ppm ascorbic acid in common packaging. All the treatments were stored in -18 ºC for 6 months after freezing by a spiral freezer in -35 ºC. Chemical, microbiological and sensory evaluations were determined from time 0 and after that monthly until the 6th month. The TVB-N value increased during the storage period but it never passed out of the standard range. The TBA value increased in all treatments but in ascorbic acid treatment it was significantly lower than the other two groups. The pH amounts during storage period decreased in all treatments homogeneously. Microbial counts in all treatments and especially in vacuum packed burgers decreased during the storage period. Organoleptic test demonstrated the preference of burgers treated by ascorbic acid. The shelf life of control group and burgers with vacuum packaging was determined 3 months at least. The shelf life of treated burgers with ascorbic acid was determined about 6 months specially based on the TBA index and sensory evaluation. Vacuum packaging was more effective to protect burgers of chemical and microbial changes compared to common packaging.
Volume 1, Issue 1 (3-2013)
Abstract
Aims: Drug users form the main HIV-affected group in Iran. About two-third of all the individuals affected by HIV in Iran are those who use drug through injection. The aim of this study is to determine the effect of health belief model (HBM) on prevention of HIV transmission among the opiate-dependent population in Zarandieh. Methods and Materials: This is a quasi-experimental intervention study carried out on 49 addicted men in Zarandieh. was collected using a questionnaire, based on HBM and the group completed the questionnaire. According to the pre-test, the educational intervention was designed and implemented. Three months after the intervention, the post-test was performed and analyzed using the primary questionnaire and χ2, T-test. Findings: The findings indicated that the mean scores of HBM Model constructs (self-efficacy, susceptibility, severity and benefit) increased significantly after intervention and the perceived barriers decreased (p< 0.001). Also, the history of HIV testing reported 8%before intervention, while the rate increased to 48.6% after intervention. Conclusions: This finding provides initial support for designing and implementation of health education program, based on the HBM on Preventing HIV transmission among Opiate-dependent population.
Volume 1, Issue 1 (NO. 1- 2011)
Abstract
One of the most important issues that organizations face is how to motivate employee to perform their roles well, thus ensuring that organization to retain its effectiveness. Indeed, specific set of employees' behaviors, discretionary ones that employees perform for organization that can significantly affect on organization’s success specifically. These behaviors are called organizational citizenship behaviors, defined as discretionary work behaviors that that have not been recognized directly or explicitly by the formal reward system, and in the aggregate, they promote the functioning of the organization. In this study has tried to investigate relationships between organization ethical values, organizational justice, organizational commitment, ethical behavior and organizational citizenship behaviors in Staff part employees of Payam Nour University (Tehran branch). In respect to purpose, this study is applied and in respect to doing method and data collection, is descriptive-analytic. LISREL and structural equation model were used for testing the hypotheses. The results of this study indicated that organization ethical values positively affects on procedural and distributive justice. Procedural and distributive justice positively affects on organizational commitment. Also organizational commitment positively affects on ethical behavior. Ethical behavior positively affect on sportsmanship and altruism dimensions of organizational citizenship behaviors.
Volume 1, Issue 1 (11-2009)
Abstract
Ethnocentrism is a kind of cultural belief, according to which an indivivalues, norms and life style of his/her own ethnic group superior to the other ones. Eethnocentrism is based on some stereotypes and in multiethnic societies, it hinders the development of interethnic social relationships. In this paper a secondary analysis of available data about eight Iranian ethnic groups of Azari, Kord, Lor, Arab, Fars, Balooch, Torkman and Talesh is done and the results indicate that ethnocentric attitude is high among all of the mentioned groups. The lowest and highest rates of ethnocentrism can be attributed to Arabs and Balooch ethnic groups respectively. Considering the effect of ethnocentrism on interethnic relations, our findings show that ethnocentrism weakens intensity, quantity and generality of communal, cultural and political interethnic relationships and increases conflict interethnic relationships. In addition ethnocentrism is an impediment to the formation of collective identity among the investigated ethnic groups. dual takes the
Volume 1, Issue 1 (9-2015)
Abstract
The list of forty one subgenera of the genus Andrena from Iran is given. The list provided here is based on a detailed study of all available published data. Four subgenera and five species are recorded for the first time from Iran, including Andrena (Cnemidandrena) fuscipes (Kirby, 1802), Andrena (Lepidandrena) curvungula (Thomson, 1870), Andrena (Lepidandrena) pandellei (Pérez, 1895), Andrena (Parandrena) sericata (Imhoff, 1868) and Andrena (Platygalandrena) tecta (Radoszkowski, 1876). Ecological notes on the newly recorded species are briefly discussed.
Volume 1, Issue 1 (2-2016)
Abstract
Background: Musculoskeletal disorders (MSD) represent one of the most frequently occurring and costly occupational issue in nursing. The nursing profession is one of the most stressful occupations today, because of the quantity and diversity of risk factors associated with the work environment. The aim of this study was to examine the relationship between burnout syndrome and musculoskeletal disorders. Material and Methods: In this cross-sectional study a questionnaire survey was carried out among 415 nursing personnel in five educational hospitals in Hamedan, Iran. Data were collected through two unnamed questionnaires including Maslach Burnout Inventory, Visual Analogue Scale (VAS). Results: Statistical analysis showed that the most commonly painful regions among the nurses were lower back (5.53%), left foot (5.08%), and head and neck (4.43%), right foot (4.90%), right knee (3.84%) and left knee (3.74%). The lowest pain, were found to be in right and left elbows (1.99%) and (1.91%), respectively. Also emotional exhaustion, depersonalization and personal accomplishment has significant correlation with musculoskeletal disorders (P = 0.000, r = 0.122). Conclusions: The results showed high prevalence of MDS among Iranian nurses that could be due to emotional exhaustion and depression.
Volume 1, Issue 1 (Autumn 2017)
Abstract
In this research,nanocomposite coatings based on epoxy containing pristine graphene oxide and starch-modified graphene oxide are prepared and characterized by Fourier transfer infrared spectroscopy, andtheir crosslinking behavior is studied using nonisothermal differential scanning calorimetry.These nanocomposites, because of having platelet-like nanomaterials inside and their organic origin, can be applied as coating on metal surface in diverse industries.The reason behind using starch was its natural basis and abundance of hydroxyl groups in its structure which can take part in crosslinking reaction with epoxide. Neat epoxy systems having amine curing agent, and nanocomposites containing epoxy, amine curing agent, andpristine or starch-modified graphene oxide nanosheets were cure at different heating rates to assess their curing behavior. Change in hearing rate of test caused change in onset and peak temperature of the exotherm curves and consequently heat of reaction changed. It was observed that the presence of the graphene oxide nanosheets hindered the crosslinking reactions, while surface modification of them with starch natural polymer compensated for such a hindrance via catalytic role of starch, and increased crosslink density of system.
Volume 1, Issue 1 (Autumn 2017)
Abstract
The adsorption of polymeric systems onto reservoir rock through altering the wettability of rock surface improves oil recovery and reduces the unwanted water production. . In this study, the adsorption behavior of dilute polymeric systems based on sulfonated polyacrylamide on the glass particles surfaces (representative of sandstone reservoirs) was investigated and the effect of this phenomenon on changing their surface properties was examined. Results show that crosslinked polymeric samples have lower adsorption on glassy surface comparing with uncrosslinked sulfonated polyacrylamide solution. Furthermore, the contact angle tests results showed that crosslinked samples change the surface property of glass particle less than sulfonated polyacrylamide solution. In addition the Langmuir isotherm model fitted the isotherm data better than the Freundlich model for these dilute polymeric systems. Furthermore, study of the thermodynamic of adsorption showed that their adsorption behavior on glassy surfaces is a spontaneous and exothermic process.
Volume 1, Issue 1 (Winter 2018)
Abstract
Abstract
Aims: Affected by natural and human phenomena, the spatial order forms the urban network. In a balanced urban system, due to hierarchical functions and activities in different cities, and fair provision of services to the existing population, there are hierarchical links between cities. The aim of this study was to investigate the urban network based on functional analysis and factors affecting the urban network deformation in Khorasan Razavi province.
Instruments and Methods: Using survey research method, the present descriptive-analytical study was conducted in 2015 among 118 experts of the provincial government, Road and Urban Development Office of Khorasan Razavi province, Governorate, Municipalities, University Jihad of Ferdowsi University, Geography professors of Ferdowsi University of Mashhad, and mayors of Khorasan Razavi province; In this study, convenience sampling method was used. The research tool was researcher made questionnaire. Factors affecting spatial imbalance were evaluated through structural equation modeling and confirmatory and exploratory factor analysis, using SPSS 22 and Lisrel 8.52 software.
Findings: Economic, infrastructural, and political factors had the greatest effect on spatial imbalance with factor loading of 0.77, 0.75, and 0.75, respectively.
Conclusion: Mashhad is at the highest and Bajgiran is at the lowest level in terms of development factors. Among the factors influencing the spatial imbalance, the changes in the country's division in the provincal level (change village to city), centralized system governance, the lack of attention to the role of the middle cities in division of labor (political factors), the focus of activities in metropolises, disproportionate allocation of credits at the provincial level, the focus of roles in Mashhad (economic factors), and the focus of superior educational and health-care services (infrastructural factors) have a more effective role.
Volume 1, Issue 1 (Winter 2023)
Abstract
Nowadays, application of enhanced oil recovery methods has increased; therefore it’s necessary to determine their impacts on environment and human life. So, this research investigates the environmental impacts of conventional enhanced oil recovery methods and new methods such as using electromagnetic waves, ultrasound waves, and nanoparticles. The investigations show that electromagnetic waves and ultrasound can effectively remove many environmental pollutants. Characteristics of the wave and the type of formation determine that these waves have different effects on the formation, and efforts should be made to understand these effects to prevent damage to the formation. Nanoparticles can also reduce the quantity of pollutants in the environment. According to the mechanisms of entrapment of nanoparticles in the porous medium, they may remain in the reservoir and find their way to the underground water over time, so their environmental effects should be considered in the long term. A better knowledge of new methods of increasing oil extraction will lead to the identification and use of more suitable methods with less environmental effects (compared to conventional methods).
Volume 1, Issue 1 (Winter 2023)
Abstract
Low Intensity Magnetic Separators (LIMS) are widely used in research and industry. The design of this separator is based on drum rotation inside a tank media, so that a permanent magnets placing inside the drum as an angle form, produces a magnetic field. In this study, the behavior of magnetic and none-magnetic particles of a pulp, flowing through a magnetic field in the wet LIMS, was simulated and validated by experimental results. The magnetic field variables were calculated in an FEM based simulator (COMSOL Multiphysics); while particles’ tracking was done applying CFD numerical method, enhanced by discrete phase model (DPM). The difference between the results of the simulation and the magnetic separation experimental test (recovery of magnetic particles in the concentrate product) was 16.4%. In order to quantify the results of the simulation, magnetic separation simulation was performed by changing two variables affecting the magnetic separation process (variables of particle size of the input pulp feed particles and solid percentage of input pulp) and corresponding experiments. Comparison of laboratory and simulation results showed that the trend of simulation results is consistent with laboratory results of the weight recovery (in both variables under study), so that the maximum simulation error is related to the size of 125 microns (16.5 %) and the lowest simulation error was in 180 microns (11.4 %). Also, the lowest simulation error in the weight recovery prediction was related to the pulp feed solid percentage of 15% (equivalent to 14%) and the highest simulation error was in 30% pulp feed solid percentage (16.9 %). This proposes that FEM-DPM-CFD coupling model, can be applied for simulation, optimization, design and construct
Volume 1, Issue 1 (Spring and Summer 2024)
Abstract
The relationship between Iran and Africa has had a long history including various aspects specially cultural issues. Their relationship, despite its ups and downs, has continued to work. The cultural relationship between the two countries has undergone many changes. These transformations have occurred both in Iran, Africa as well as the whole world. This study intends to examine and evaluate this era and the nature of these relations before and after Islamic revolution in Iran. The main question raised in this regard is that considering the good historical back ground, what has been the orientation of Iran's foreign policy in these periods? Studies point out that the relations between Iran and African countries affected by domestic or international approaches have had ups and downs. Apparently, during Pahlavi's regime, in spite of some measures taken to establish relations with African countries, these relations didn't have coherent policy and the relations with the North African countries has had more priorities over relations with sub-Saharan countries. Moreover, Iran’s relations with some countries such as the Apartheid government, or its military and financial support for some governments have provoked skepticism towards Iran among the other African countries, and has led to the cut off of the relations with Iran. However, victory of the revolution in Iran created a new development in relations with Africa, and considering the approaches and goals of this revolution, relations with Africa has been placed in the highest foreign policies of IRI. Although, even in this age, these relationships have gone under lots of ups and downs at the time of the ruling of various governments in IRI.
Volume 1, Issue 2 (6-2012)
Abstract
Biochemical characteristics of α-amylase in the digestive system and head glands of Cryptolaemus montrouzieri, a key predator of citrus mealybug, Planococcus citri (Pseudococcidae), were studied. The major isoform of α-amylase with the same molecular weight was detected in both gut and head glands loaded on polyacrylamide-starch gel electrophoresis. Moreover, a minor band with much lower intensity was observed in zymogram analysis of gut. Results showed that the specific activity of α-amylase from head glands (0.89 ± 0.02 μmol/min/mg protein) was significantly more than that of digestive system (0.76 ± 0.01 μmol/min/mg protein) in common condition (temperature equal to 25 ± 1 oC). The optimal pH and temperature for α-amylases activity were determined to be nearly 4 and 50°C in digestive system and 6 and 60 °C in head glands, respectively. EDTA (Ethylenediamine tetra acetic acid), Mg2+, Na+, Co2+, Fe2+ and Ca2+ inhibited the enzyme activity but Ba2+, Zn2+, Hg+ and K+ enhanced enzyme activity in digestive system. EDTA and all tested metal ions except Ba2+ inhibited the enzyme activity of head glands. Detectable levels of α-amylase activity in the insect reflect adaptation of the coccinellid for using starch granules or sugars (honeydew; sugary excreta of homopterans; and nectar) as a source of food in addition to predatory habits.
Volume 1, Issue 2 (6-2013)
Abstract
Volume 1, Issue 2 (6-2016)
Abstract
Background: Knee osteoarthritis (OA) is a major public health problem leading to chronic pain and increased years lived with disability This study aimed to assess lifestyle behavioral management in patients with Knee osteoarthritis among Iranian patients up to 6 months.
Methods and Materials: This study conducted at the Rheumatology Research Center of Tehran University of Medical Sciences (TUMS) in Tehran, Iran. In this educational controlled trial study, 130 eligible participants took part in control group (n = 66) and received just prescribed medications, or intervention group (n = 64) who received the lifestyle behavioral management plus medication. The program involved three two-hour and two one-hour group sessions over a one-week period. Data based on demographic characteristics and risky behaviors questionnaire as well as Functional Knee Assessment Test (FKAT) were collected at initial, 3-, and 6-month follow ups and analyzed by using SPSS18.
Results: Of 130 participants, five individuals from intervention and eight individuals from control group were excluded over 6 months. Totally, 117 eligible participants in two groups of intervention (n = 59), and control (n = 58) completed the study. The mean age of participants in intervention and control group at base line was 59. 03 ± 6. 13 and 57. 85 ± 9. 31 years respectively. Despite being the same at initial time (P > 0. 05), Repeated Measure ANOVA test showed Significantly better improved disability in intervention group over time (P < 0. 001). Compared with control group, preventive behaviors were improved significantly in intervention group (P < 0. 05)
Conclusions: This study revealed that the multidisciplinary program could significantly reduce risky behaviors and disability up to six months in intervention group. Thus, due to lack of lifestyle behavioral management in health care system of Iran, to embedding this program into clinical practice for managing knee OA pain is recommended.
Volume 1, Issue 2 (winter 2018)
Abstract
In general, temporary well plugging is essential for repairing of oil and gas wells due to their long life time. One of the newest methods used for this purpose is gel polymer plugging. The strength of the gel in the well conditions is one of the most important challenges in the application of gel polymer in the temporary well plugging in work over operation. In this study, silica nanoparticles were used to improve the strength of polymer hydrogels. The bottle and rheological tests were used to determine the gel strength in desired well conditions (high temperature and high salinity). Also, the gel strength properties and swelling behavior were studied in various conditions such as distilled water, formation water, tap water and oil. It was observed that the strength of the gel increased from 520Pa to about 36kPa (5000% increase) by adding nanoparticles. Also, the gel swelling in the aqueous solution has been significantly reduced. Based on the results obtained in this study, a polymer gel containing 9 wt.% of silica nanoparticles with structural strength and thermal stability at 90 °C was introduced for field studies.