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Showing 6 results for Nafar
Volume 1, Issue 1 (3-2013)
Abstract
Rainfall is recognized as one of the main triggering factors of landslides. Researchers have long attempted to determine the amount of precipitation required to trigger slope failures. One of the landslide zones in Iran is Chaharmahal & Bakhtiari province where many landslides cause high casualties in recent decades. It is significant that most of these landslides occur after a rainy period. Thus, determination of rainfall thresholds in this province seems to be necessary as the first step to present an effective landslide warning system. In this research, we tried to introduce some antecedent rainfall thresholds for deep-seated landslides. The antecedent periods considered for the events examined in this study were 5, 10, 15, 20, 25, 28 and 30 days. Since most of landslides occurred by cumulative rainfall for more than 10 days, the results of 5 days and shorter time periods appear not logically connected. We have also established rainfall thresholds for the 15-day antecedent period and 2, 3 and 5 days rainfall events. Results indicate that for 10 to 30 days antecedent periods, mean total rainfall needed to induce landslides varies between about 140 and 280 mm. Finally, we recommend more research on relation between rainfall characteristics and destabilization of different soil classes in the study area (especially clayey-marly deposits).
Volume 1, Issue 2 (6-2013)
Abstract
Evapotranspiration is one of the most important components of the hydrological cycle which is directly influenced by atmospheric conditions. This study investigated annual and seasonal trends in reference evapotranspiration (ET0) and its key influencing climatic variables during 1966-2005 at 10 stations in southern Iran (with centrality of Fars province). First, multivariate regression analysis was performed to identify the major meteorological variables affecting ET0. Second, annual and seasonal trends in climatic variables as well as ET0 were assessed using the Mann-Kendall test, Spearman's rho, the Pearson correlation and linear regression to evaluate their contribution to the temporal trend in ET0. Results suggested that the more effective variables for ET0 were wind speed (U2), relative humidity (RH) and sunshine hours (n). Also, the majority of trends in seasonal and annual ET0 were non-significant and after that decreasing and increasing trends had higher frequencies. In addition, distributions of relative frequencies of trend types at all considered time-scales were similar for both parametric and non-parametric techniques. Hence, the disagreement between parametric and non-parametric trend results did not depend on the degree of normality in the annual and seasonal ET0 distributions in the study area.
Razieh Abdolvahabi, Abdolfatah Sarrafnejad, Mohsen Nafar, Aliakbar Amirzargar,
Volume 2, Issue 1 (3-2016)
Volume 2, Issue 1 (3-2016)
Abstract
Background: The innate immunity plays an important role in the host response to transplantation by Toll-like receptors and results in development of acute allograft rejection. The aim of this study was to evaluate the association of TLR2 and CD14 (co-receptor) gene polymorphisms with acute rejection in kidney transplant recipients. Methods : The study was conducted in a population of 239 subjects consisting of 71 patients with acute rejection, 71 patients without acute rejection (SGF) and 97 Healthy Control (HC). The allele and genotype frequencies of TLR2 (R753Q, rs5743708) and CD14 (-159 C>T, rs2569190) polymorphisms were genotyped by Real-time PCR in the study groups. Results : Genotype distribution of CD14 -159 polymorphism was significantly different in AR vs. SGF and HC. CD14 -159 TT genotype was more prevalent in rejection than SGF and HC (P<0.0001, P<0.007, respectively). Also Graft loss, defiened as need of dialysis after acute rejection, was occurred in 24 patients (33.8%) from AR group. The frequencies of three genotype in CD14 (TT, CT, CC) in rejection With Graft loss were 75.0%, 20.8% and 4.1% respectively, While 25.5%, 31.9% and 42.5% in rejection without Graft loss (P<0.0001 for TT vs. CT, CC). Many recipients with AR were involved with graft loss had CD14 -159 TT genotype, whereas only a few recipients without graft loss had TT genotype (p<0.0001). Conclusion : Therefore, due to the importance of CD14 polymorphism (-159 C/T, rs2569190) in disease progression and also as a biomarker, could be considered as a crucial therapeutic target in early prognosis of acute rejection
Volume 6, Issue 1 (winter 2021)
Abstract
Aim: This study aimed to investigate the effect of two weeks of vitamin D3 supplementation on some indices of Delayed Onset of Muscle Soreness (DOMS) after eccentric exercise.
Method and Materials: In this semi experimental study, 20 nonathletic male collegiate students (19.75±1.29 years) participated in the study voluntarily and were divided randomly into two groups of experimental (n=11) and placebo (n=9). The experimental group consumed vitamin D3 (Cholecalciferol) containing 50000 IU while the placebo group took apparently similar capsules containing starch like, two capsules for two weeks. To induce DOMS, participants performed a step protocol that included four sets (5 minutes for each set), with a 1-minute of rest interval between each set using a 46 cm-step. Range of Motion (ROM) of low extremity joints and circumferences, and Visual Analog Scale (VAS were measured before, immediately after (Time 0), and 24 hours (Time 1) and 48 hours (Time 2) after eccentric exercises.
Findings: This study showed that thigh Thigh circumference increased following eccentric exercise in the placebo group, while it did not change significantly in the experimental group (p>0.05). There was no significant difference between the two study groups regarding other variables (P>0.05). Vitamin D3 supplementation with the dosage and duration used in the present study reduced the limited symptoms of DOMS. Future studies of longer duration or higher dosage of vitamin D supplementation are recommended.
Conclusions: According to the finding of this study, vitamin D3 supplementation could not reduce the limited symptoms significantly. However, future studies are suggested to evaluate the effect of higher dose or longer duration of vitamin D supplementation on DOMS.
Method and Materials: In this semi experimental study, 20 nonathletic male collegiate students (19.75±1.29 years) participated in the study voluntarily and were divided randomly into two groups of experimental (n=11) and placebo (n=9). The experimental group consumed vitamin D3 (Cholecalciferol) containing 50000 IU while the placebo group took apparently similar capsules containing starch like, two capsules for two weeks. To induce DOMS, participants performed a step protocol that included four sets (5 minutes for each set), with a 1-minute of rest interval between each set using a 46 cm-step. Range of Motion (ROM) of low extremity joints and circumferences, and Visual Analog Scale (VAS were measured before, immediately after (Time 0), and 24 hours (Time 1) and 48 hours (Time 2) after eccentric exercises.
Findings: This study showed that thigh Thigh circumference increased following eccentric exercise in the placebo group, while it did not change significantly in the experimental group (p>0.05). There was no significant difference between the two study groups regarding other variables (P>0.05). Vitamin D3 supplementation with the dosage and duration used in the present study reduced the limited symptoms of DOMS. Future studies of longer duration or higher dosage of vitamin D supplementation are recommended.
Conclusions: According to the finding of this study, vitamin D3 supplementation could not reduce the limited symptoms significantly. However, future studies are suggested to evaluate the effect of higher dose or longer duration of vitamin D supplementation on DOMS.
Volume 10, Issue 3 (Summer 2019)
Abstract
Nanotechnology is currently one of the promising approaches for cancer diagnosis and treatment. Among different materials that so far have been used for drug delivery, the systems based on the polymers are more attractive, due to their simple manufacturing processes and diversity in polymer functionalization and modification methods. Polyethyleneglycol (PEG) and polycaprolactone (PCL) are two FDA approved and biocompatible synthetic polymers which frequently have been used in the pharmaceutical industry. Apart from the delivery carriers, the active ingredient’s safety is also very challenging in case of cancer therapeutics. The chemotherapy agent’s side effects are one of the main patients’ death in many cancers. The naturally extracted curcumin is one of the most interesting anti-cancer agents with a proven selective effect on the cancerous cells which results in minimum side effects during the treatment. Curcumin has been tested as the main agent or in combination therapy of various cancers. Numerous studies have shown the safety and efficacy of curcumin at different administered doses. However, the main obstacle in the application of curcumin is its low aqueous solubility and low and variable bioavailability after administration. For that, in this study, we tried to enhance the solubility of curcumin using a novel diblock copolymer of PEG-PCL nanoparticulate system. At first, the PEG-PCL copolymer was synthesized and then characterized by GPC, FTIR, and H NMR methods. After that, curcumin was loaded in the micellar structure of PEG-PCL at an optimized encapsulation approach and then the toxicity of the prepared nanoparticles was assessed in MCF-7 cell culture. The results showed that the prepared nanoparticles could efficiently entrap the hydrophobic molecules of curcumin, improve its solubility and increase in vitro activity against cancer cell line.
Volume 22, Issue 1 (Spring 2018)
Abstract
Introduction
While various political, social and economic factors have changed in Iran during the last decades, the urbanization rate has risen from 28% in 1921 to 74% in 2016. In the last few decades, reclassification of villages to cities can be noticed as one of the most important dimensions of urbanization process in Iran. Among these, factors affecting on reclassification of rural settlements as cities and the impacts of this change on urban system and spatial organization of regions have attracted a lot of attention among researchers. Although the process of reclassification of villages as cities varied with the degrees of intensity and speed across the country, but this has been more important in some regions. One of these regions is Guilan province located in the north of Iran. The existence of susceptible agricultural lands, existence of the most important forestry areas of the country, aggregation of urban and rural settlements in this region are some factors that make this more important subject for wider researches. Accordingly, the questions that this article seeks to respond is, what is the most dominant process in reclassification villages as cities in Guilan and what impacts had on this region's urban system?
Reclassification of villages as city refers to factors and processes that lead to the recognition of a village as a city. There are three points of view in this regard. The first emphasizes on the transformation of villages to city as a natural process. In this view, the growth of population size of rural communities leads to a change in economic, social and physical dimensions. Economically, the natural process is the same as market process in which economic forces freely lead to the reshaping of human settlements. The second view emphasizes on the involvement of political agents on the reclassification of villages as cities. The recognition of urban and non-urban centers in countries is important for various administrative and political tasks, such as distribution of governmental credits, allocation of facilities and etc. Therefore, it is important for governments to determine relevant criteria for the reclassification of rural settlements as urban areas. However, the reclassification of villages as cities with natural or political interventions cannot always be a reasonable and acceptable process, because of necessities in regional development. It is sometimes necessary to strengthen rural settlements as an urban settlement; that is the third point. The roots of this view, backs to 1960s and 1970s, and emergence of new perspectives between various views of regional development, can be described as small towns approach.
Methodology
This research can be considered as an inductive-deductive research. The method used in this research is a descriptive-evaluative method and data collection method is documentary. This paper tries to evaluate the status and processes associated with the reclassification of villages as cities in Guilan province in Iran. With the population more than 5,000 people has been assumed as the main criterion for natural changes. Political, centrality as an index for political intervention and introducing in development plans as a potential settlement for reclassifying as city was counted as planning factor.
Results and discussion
The Guilan province in Iran is always considered as one of the agricultural hubs of the country and is divided into 16 counties. In the two censuses before the Islamic Revolution (excluding the 1956 census as the basis), nine cities were added to this region's urban system, where only one city (Rudbar) had less than 5,000 people. In addition, all of these cities had municipalities before being counted as cities. Therefore, it can be said that before the Islamic Revolution, the political process of recognition of a city has preceded from natural changes. After the Islamic Revolution, it was attempted to reconcile the identification of urban areas in the censuses and administrative system. Statistical surveys of cities based on criteria's that set out in the theoretical framework, reveals that 19 cities have been shaped from natural process and 24 cities have been shaped due to political interventions. Study of urban system of this region shows that most of new cities in Guilan province have less than 5,000 inhabitants. Urban Primacy Index reveals that since 1996, there has been a great concentration on Rasht as the primate city. Rank-size rule analysis indicates imbalance in urban hierarchy of this province. Therefore, it can be said that the emergence of low-population cities in this province influenced mainly by the government's policies and decisions, couldn't lead to an efficient change in urban hierarchy of this province.
Conclusion
The results of this research show three basic issues on the Guilan province's urban system: 1) Dominance of Rasht as capital city, which according to the census of 2016, includes near of 42.4% of the province's urban population. 2) The absence of middle size cities in its true meaning, as consolidators of urban network, which has led to an urban bias between primate city and small cities. 3) Sharp increase in the reclassification of villages as cities over the last few decades, especially after the Islamic Revolution. The rapid rate of reclassification of villages as cities in recent decades, has caused these cities not to be able to provide a significant instance on the urban hierarchy. Therefore, the reclassification of villages as cities has not led to adjustment of urban system, and there is a need for some different strategies to reshaping spatial organization of this province. In this case, the middle-size cities development strategy can be considered as one of the efficient strategies.
While various political, social and economic factors have changed in Iran during the last decades, the urbanization rate has risen from 28% in 1921 to 74% in 2016. In the last few decades, reclassification of villages to cities can be noticed as one of the most important dimensions of urbanization process in Iran. Among these, factors affecting on reclassification of rural settlements as cities and the impacts of this change on urban system and spatial organization of regions have attracted a lot of attention among researchers. Although the process of reclassification of villages as cities varied with the degrees of intensity and speed across the country, but this has been more important in some regions. One of these regions is Guilan province located in the north of Iran. The existence of susceptible agricultural lands, existence of the most important forestry areas of the country, aggregation of urban and rural settlements in this region are some factors that make this more important subject for wider researches. Accordingly, the questions that this article seeks to respond is, what is the most dominant process in reclassification villages as cities in Guilan and what impacts had on this region's urban system?
Reclassification of villages as city refers to factors and processes that lead to the recognition of a village as a city. There are three points of view in this regard. The first emphasizes on the transformation of villages to city as a natural process. In this view, the growth of population size of rural communities leads to a change in economic, social and physical dimensions. Economically, the natural process is the same as market process in which economic forces freely lead to the reshaping of human settlements. The second view emphasizes on the involvement of political agents on the reclassification of villages as cities. The recognition of urban and non-urban centers in countries is important for various administrative and political tasks, such as distribution of governmental credits, allocation of facilities and etc. Therefore, it is important for governments to determine relevant criteria for the reclassification of rural settlements as urban areas. However, the reclassification of villages as cities with natural or political interventions cannot always be a reasonable and acceptable process, because of necessities in regional development. It is sometimes necessary to strengthen rural settlements as an urban settlement; that is the third point. The roots of this view, backs to 1960s and 1970s, and emergence of new perspectives between various views of regional development, can be described as small towns approach.
Methodology
This research can be considered as an inductive-deductive research. The method used in this research is a descriptive-evaluative method and data collection method is documentary. This paper tries to evaluate the status and processes associated with the reclassification of villages as cities in Guilan province in Iran. With the population more than 5,000 people has been assumed as the main criterion for natural changes. Political, centrality as an index for political intervention and introducing in development plans as a potential settlement for reclassifying as city was counted as planning factor.
Results and discussion
The Guilan province in Iran is always considered as one of the agricultural hubs of the country and is divided into 16 counties. In the two censuses before the Islamic Revolution (excluding the 1956 census as the basis), nine cities were added to this region's urban system, where only one city (Rudbar) had less than 5,000 people. In addition, all of these cities had municipalities before being counted as cities. Therefore, it can be said that before the Islamic Revolution, the political process of recognition of a city has preceded from natural changes. After the Islamic Revolution, it was attempted to reconcile the identification of urban areas in the censuses and administrative system. Statistical surveys of cities based on criteria's that set out in the theoretical framework, reveals that 19 cities have been shaped from natural process and 24 cities have been shaped due to political interventions. Study of urban system of this region shows that most of new cities in Guilan province have less than 5,000 inhabitants. Urban Primacy Index reveals that since 1996, there has been a great concentration on Rasht as the primate city. Rank-size rule analysis indicates imbalance in urban hierarchy of this province. Therefore, it can be said that the emergence of low-population cities in this province influenced mainly by the government's policies and decisions, couldn't lead to an efficient change in urban hierarchy of this province.
Conclusion
The results of this research show three basic issues on the Guilan province's urban system: 1) Dominance of Rasht as capital city, which according to the census of 2016, includes near of 42.4% of the province's urban population. 2) The absence of middle size cities in its true meaning, as consolidators of urban network, which has led to an urban bias between primate city and small cities. 3) Sharp increase in the reclassification of villages as cities over the last few decades, especially after the Islamic Revolution. The rapid rate of reclassification of villages as cities in recent decades, has caused these cities not to be able to provide a significant instance on the urban hierarchy. Therefore, the reclassification of villages as cities has not led to adjustment of urban system, and there is a need for some different strategies to reshaping spatial organization of this province. In this case, the middle-size cities development strategy can be considered as one of the efficient strategies.
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