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Volume 0, Issue 0 (2-2024)
Abstract
The present study aimed to evaluate pragmatic skill of adult right and left hemispheres damaged Persian speaking patients using the Persian version of the Montreal Protocol for the Evaluation of Communication (M.E.C.). The statistical populations of the study were 10 adults, right and left hemispheres damaged Persian speaking patients due to cerebrovascular accident (CVA). Two sets of tests were used in the present study. The first ones were screening tests included Lateral Preference Inventory (Corn test), Mini Mental State Examination (MMSE) and Persian Diagnostic Aphasia Battery (EQ1). The Performance of patients in protocol subtests were evaluated and compared with each other individually, intragroup and intergroup. Data were analyzed using inferential statistical methods and no meaningful relations were found between them. These findings indicated that damage to the right and left hemispheres of the brain leads to pragmatic impairments. However, damages to the right hemisphere increases the severity of pragmatic impairments more than damages to the left hemisphere.
Volume 0, Issue 0 (2-2024)
Abstract
The aim of this study was to investigate the effect of cognitive functions on verbal fluency. For this purpose, some cognitive functions and verbal fluency in adult patients with right hemisphere damage were evaluated. The methodological nature of this study is descriptive-analytical. The statistical population of the study consists of 18 adult patients with right hemisphere damage and 18 healthy adults. Selective attention test, memory test, clock drawing test (visual neglect) and verbal fluency test were used to evaluate cognitive functions and linguistic skill of the subjects. Research data were analyzed using descriptive and inferential statistics. The findings showed that there is a significant difference between performance of adult patients with right hemisphere damage and healthy adults in the cognitive tests (P< 0.05). Likewise, in the verbal fluency test, there is a significant difference between performance of adult patients with right hemisphere damage and healthy adults (P< 0.05). In addition, the research findings showed that there is a correlation between cognitive functions and verbal fluency. Also, the results showed that damage to the right hemisphere of brain can lead to disorders in cognitive functions of patients with right hemisphere damage. Furthermore, it seems that impairment in cognitive functions can cause problems in language skills.
Volume 0, Issue 0 (8-2024)
Abstract
The effective design of structures resistant to seismic vibrations is one of the main concerns of structural engineers to deal with damages caused by earthquakes, which can withstand more earthquake forces with methods such as energy dissipation. Recent earthquake records show that the earthquake record characteristic of the near area differs from the earthquake records of the far area. Among these characteristics, it can be mentioned that the pulse-type state of these records, as well as the high maximum speed and ground displacements. For this reason, these types of records increase the seismic requirements of the structure compared to normal earthquakes. The map of faults and seismic zoning of Iran shows that important urban points such as Tehran, Tabriz, etc. have high seismicity and are located near the fault. Therefore, it is necessary to design and build structures that can properly withstand the features of near-fault earthquakes, this issue reveals the understanding and recognition of the behavior of structural systems and the structure's response to the special features of near-fault earthquakes. This article first investigated the seismic evaluation of three existing 4, 8, and 12-story steel structures with lateral load-resisting systems. Then the desired structure was strengthened using a friction damper, and finally, the acceleration recorder was applied to the structure in the near- and far-fault earthquake zone case study. The seismic demand of the retrofitted structure was investigated in ANSYS Workbench finite element software, which was done in the form of modal analysis, floor drift displacement, structure acceleration response, and von Mises stress. For seismic validation, a two-story, single-span steel frame has been used. The dynamic load used was 0.5g based on the north-south component of the El Centro earthquake (1940) with a maximum acceleration scaled to 50 cm/s. To validate the numerical results, the horizontal displacement of two points on the first and second floor was compared with experimental data, and an acceptable accuracy was obtained. The results of the maximum acceleration at the highest point of the building showed that in a far-fault earthquake zone, the best effect of dampers was on 8-story buildings with a 77% decrease, and in a near-fault earthquake zone, it was related to a 4-story building with a 66.4% decrease in acceleration. Stress in near- and far-fault earthquake zones, the best effect of dampers was on 4-story buildings with 83% and 84% reduction, respectively. In a far-fault earthquake zone, the best effect of dampers was on 8-story buildings with a 44% reduction in maximum displacement, and in a near-fault earthquake zone, it was related to a 4-story building with a 61% reduction in acceleration.
Volume 0, Issue 0 (8-2024)
Abstract
Masonry infills are generally assumed as non-structural elements in structural calculations and are not modeled. However, observations after past earthquakes have shown that masonry infills have significant effects on the seismic performance of structures and their seismic behavior should not be neglected. Additionally, the absence of masonry infills in the first story, which is common in structures for commercial and architectural reasons, has led to the occurrence of the soft story phenomenon in past earthquakes. The maximum interstory drift ratio (MD) is the most important criterion for assessing seismic damage and the occurrence of collapse in structures. In this study, the seismic performance of 3- and 9-story steel moment resisting frames (MRFs) with masonry infills was evaluated using a probabilistic framework considering the record-to-record variability. Two configurations were considered for the masonry infills including fully infilled and open ground story configurations. The seismic performance of the MRFs with these two configurations was compared to that of bare MRFs. The OpenSees software was employed for nonlinear modeling of the structures and masonry infills were modeled using single compression-only struts. The fundamental periods of structures with masonry infills significantly increase after the failure of the masonry infills. To evaluate these effects, Rayleigh damping was modeled using the conventional method and a modified method, which considers the severe elongation of fundamental period due the failure of infills, and the responses obtained from the two methods were compared. By performing incremental dynamic analyses using 78 far-field ground motion records, drift margin ratios (DMRs), drift fragility curves and mean annual frequencies of exceeding four MD levels of 0.7%, 2.5%, 5%, and 15% (λMD) were obtained for the structures. The MD levels of 0.7%, 2.5%, and 5% correspond to the performance levels of immediate occupancy, life safety, and collapse prevention, respectively. The MD level of 15% corresponds to the seismic collapse of the structures. The results indicate that the presence of masonry infills improves the drift performance of the MRFs with the fully infilled configuration. However, since the masonry infills experience failure at higher drift levels, their effectiveness decreases at these drift levels. Furthermore, the absence of masonry infills in the first story leads to the soft story phenomenon at lower drift levels, and therefore, the performance of the structures with the open ground story configuration is worse than that with the fully infilled configuration. It should be mentioned that at higher drift levels, due to the failure of masonry infills, the structures with the two configurations for infills have almost the same performance and close to the performance of the bare MRFs. The amplification of the soft story phenomenon in the 9-story structure causes the performance of the structure with the open ground story configuration given some drift levels to be even worse than that of the bare structure. For example, by using the modified damping method for the 3-story structure with the fully infilled configuration, the masonry infills reduce the λMD value given MD = 0.7% by 43%, but the reduction in the λMD given MD = 15% is 19%. Based on the results obtained, the conventional Rayleigh damping method in the technical literature underestimates the responses.
Volume 0, Issue 0 (8-2024)
Abstract
The design of earthquake-resistant structures and the reduction of damages caused by them have always been considered. One of the ways to reduce earthquake vibrations in steel frames is to use cable braces. In addition, one of the ways to improve the behavior of the structure against seismic loads is the use of dampers. In this research, magnetorheological damper and cable brace are used simultaneously. To check the effectiveness of the proposed system, four steel frames including, a steel frame without cables and dampers, a steel frame with cable braces, a steel frame with magnetorheological dampers and, a steel frame with cable braces along with magnetorheological dampers, which have one-span and two spans, were selected and the behavior of this frame Assuming different conditions, under nonlinear static lateral load and seismic loads, it has been checked in SAP2000 software. By examining the results obtained from the nonlinear static analysis of the case of a one span, it is concluded that the steel frame with cable brace and magnetorheological damper reduces the lateral displacement of the frame and often the internal forces of the beam and column more than other frames. gives by examining the results of the time-history dynamic analysis of one-span and two-span conditions, it is concluded that the proposed system reduces the lateral displacement of the frame and the internal forces of the beam and column more than other frames in most of the investigated earthquakes. In other words, using the proposed systems improves the performance of the structure against lateral loads.
Volume 0, Issue 0 (8-2024)
Abstract
Climate change has become one of humanity's greatest challenges. Rising temperatures, weather fluctuations, and especially changes in precipitation and wind patterns have profound impacts on infrastructure and urban structures. These changes not only increase the risk of natural disasters but also affect the design and construction of buildings. Therefore, the development of innovative solutions to enhance the seismic performance and resilience of these buildings, especially in regions susceptible to climate change, is crucial. This study examines the performance of an 8-story steel structure with geometric irregularity in its plan against the effects of climate change, focusing on wind loading under three different wind speed increase scenarios including:1-low 2-moderate, and 3-severe. To mitigate the negative effects of these changes on the seismic performance of the structure, magnetorheological damper was employed. The entire floor slabs of the structure were considered rigid. The modified Bouc-Wen method was used to indicate damper behavior in dynamic equations of the structure and two control scenarios including passive control and active control were considered. NatHaz online wind simulator data base was used for modeling wind loading on structure and the Simulink environment of MATLAB was used to model the structure equipped with a magnetorheological damper under wind loading.
The results indicated that a slight increase in wind speed led to an average increase of 35%, while a moderate increase resulted in over 60%, and a severe increase in wind speed caused more than a 100% rise in maximum displacement, drift, and base shear responses of structure. By adding magnetorheological damper to improve the negative effects of increased wind speed on the seismic performance of the structure, the damper was able to reduce the maximum displacement, drift, and base shear of the floor where it was installed by 14%, 32%, and 38% respectively in scenario (1), by 16%, 40%, and 32% respectively in scenario (2), and by 8%, 28%, and 29% respectively in scenario (3). This indicates that the damper effectively controlled the response of the floor it is installed on and was able to mitigate the negative effects of climate change. Furthermore, this damper not only positively affected the floor it was installed on but also improved the seismic response of the roof level, maintaining its effectiveness across all three climate change scenarios. Additionally, the results indicated that the damper performs better in active control mode compared to passive mode. However, the parameters related to maximum acceleration of the floor indicates a significant increase in the active control scenario, while in the passive control scenario, no significant changes were observed. The best results were achieved in the low and moderate wind speed increase scenarios. Although in the severe wind speed increase scenario, the damper maintained its effective performance. In conclusion, it can be said that the force generated by the magnetorheological damper has intelligent adjustability, which can change based on environmental conditions and loading. This feature allows structures to respond more quickly to sudden environmental changes and provides greater safety against damage caused by climatic conditions as well as enhancing the resilience of structures against adverse weather conditions.
Volume 1, Issue 1 (4-2014)
Abstract
Background: Differentiation ofmesenchymal stem cells (MSCs) to hepatocyte-like cells could be associated with development of liver function factors. The impact of differentiation-dependent changes on DNA integrity is not well understood. In this study, hepatocytes and their progenitor stem cells were treated with aflatoxin B1 (AFB1) and amplification of selected genes linked to DNA damage was examined. Methods: MSCs and CD34+ cells isolated from umbilical cord blood (UCB) were treated with AFB1 (0, 2.5, 10 and 20 µM) in selective media supporting the hepatocyte differentiation. After 24 htreatment the DNA damage (Comet assay) and amplification rates ofP53 and β-globin genes were measured using real time polymerase chain reaction (QPCR). Results:The results show that AFB1 treatments resulted in a concentration- dependent increase in the DNA damage and suppression of the specific gene amplification. The extent of DNA damage was significantly greater in hepatocytes differentiated from MSCs when compared to those obtained from CD34+ cells. The effects of AFB1 on the rate of selected gene amplification in QPCR showed that the lesions (expressed as lesions/10 kb) in P53 and β-globin genes was significantly greater in hepatocytes derived from MSCs as compared to the cells derived from CD34+ cells. Conclusions: These data together with the results of cytochrome P450 (CYP3A4) expression in the cells suggest that the non-differentiated stem cells are probably less vulnerable to genotoxic agents as compared to hepatocytes differentiated from them.
Volume 1, Issue 3 (10-2008)
Abstract
Volume 1, Issue 3 (10-2014)
Abstract
Background: Accumulation of triglycerides in the liver i.e. steatosis, is a well-known side-effect of tamoxifen administration to patients suffering from breast cancer. Cichoriumintybus (chicory) is a plant used as traditional medicine for curing liver disorders. In this study, the effects of extract prepared from chicory roots on tamoxifen-induced liver steatosis and related biochemical factors in animal model using rats has been investigated. Methods: Female rats of Wistar strain were divided into four groups and treated as follows; 1-Control: received vehicle; 2- Chicory root-extract treated: rats were given by gavage the aqueous chicory root extract (1 g/kg body weight/day for 14 days).3- Tamoxifen-treated: rats received tamoxifen (1 mg/kg body weight/day, for 7 days). 4- Tamoxifen+chicory-group: animals received tamoxifen (1 mg/kg body weight/day for 7 days) followed by chicory extract given by gavage (1 g/kg body weight/day for 14 days). After treatment, blood was collected by cardiac puncher, plasma was separated and plasma levels of glucose, total protein, triglyceride, cholesterol,LDL-C, HDL-C and activities of ALT, AST and ALP were measured. Liver tissues were homogenized used for measuring tissue triglyceride and histological examinations. Results: The data show that tamoxifen treatment caused a significant decrease in the level of serum cholesterol, HDL-C and total protein. However, serum ALT level was increased in tamoxifen-treated rats compared to controls. Increased serum ALT in tamoxifen-treated rats was recovered in rats treated with plant extract (tamoxifen+chicory-group). HDL-C and total protein levels were unaffected in rats fed chicory extracts. Tamaxifen-treated animals showed signs of liver steatosis as shown by histological examination and accumulation liver triglyceride. The steatosis markers such as accumulated triglyceride in liver was significantly reduced due to the plant extract treatments when compared to tamoxifen-group. Conclusions: Dietary extract prepared from chicory roots is effective in modulation of tamoxifen-induced liver damage and steatosis.
Volume 2, Issue 1 (12-2019)
Abstract
Fundamentalism is one of the most important security issues in today’s world, in a way, territoriality has drawn a large part of the world’s security literature. Over the past decade, the North African region became locality of internal crisis, regional ideological and rivalries, and intra-regional powers intervention and expansion of extremist ideas that has cost and effects on both internal, regional and international levels. In the meantime, the north of the African continent, and specially Tunisia country, has created opportunities for the growth and development of ISIL’s fundamentalist organization. The present study is a descriptive-analytical research and its data and information gathering by the library method. Hypothesis of this study based on unified Field Theory of Stephen B. Jones and belive that Territoriality of Fundamentalist Organizations in Tunisaia affected by internal factors (social crisis) and external factors (intervention powers). The result of the study showed that the fragility of the government, the geographical structure, and geopolitical integration in Tunisia, along with the political and international limitations caused territoriality of fundamentalist organization and acted as an obstacle for emerging and developing of a new political entity in this country.
Volume 2, Issue 2 (6-2013)
Abstract
Hippodamia variegata is an efficient and most abundant predatory coccinellids in many countries. Understanding the ability of long-term low temperature survival in beneficial insects can be used to make better predictions about subsequent abundance and hence the biological control potential in the next spring and summer. So in this study, effects of long-term temperatures were investigated on mortality and supercooling point (SCP) of field collected (pre-diapausing) and overwintering aggregations of H. variegata adults. Unlike the pre-diapausing insects, aggregated coccinellids could easily survive at -3 and 0 °C for one month. One month acclimation at 10 °C caused more than 80% mortality in overwintering adults, indicating the higher temperatures were not appropriate for overwintering aggregated coccinellid. In December and January, when diapause was in its highest level, changing the habitat temperature did not affect SCP. Acclimation at 5 and 0 °C for one month decreased SCP of pre-diapausing adults, collected from aphid infested plants in October. Our study revealed that exposure to temperatures below 0 °C happened usually in natural condition for a long term period, may be necessary for overwintering of the coccinellid.
Volume 2, Issue 4 (12-2022)
Abstract
In his book, Finite and Infinite Goods, The prominent Christian philosopher, Robert Adams, defends a weak version of divine command theory. According to this view, the nature of moral obligations is identical with being commanded by God. His argument for view has two stages. In the first stage he tries to show that the notion of moral obligation is essentially social in its nature. That is, moral obligations are constituted by social notions such as demands or commands of a third party such as a third person or the moral community. In the second stage he argues that this third party cannot be anything but God. In this paper I will try to criticize his argument in its first stage. I will show that his reasons and arguments for the claim that moral obligations have a social nature are inconclusive.
Volume 3, Issue 2 (6-2014)
Abstract
Rosy apple aphid, Dysaphis plantaginea (Passerini), with worldwide distribution is an important pest of apple orchards. Host plant resistance is an essential component of integrated management of this insect pest. We investigated the resistance of seven apple cultivars, Malus domestica (Borkhausen), namely Granny Smith, Starkrimson, Golden Smoothee, Red Delicious, Golden Delicious, Boshghabi, and Shaki to rosy apple aphid under field and greenhouse conditions. The damage level by rosy apple aphid was significantly different among the tested cultivars precisely three weeks after infestation in both field and greenhouse conditions. The least leaf curling was observed on Shaki, while the most deformation was detected on Golden Delicious. There was positive correlation between damage in greenhouse and field studies. In addition, the lowest and highest numbers of aphids were observed on Shaki and Golden Delicious, respectively. Consequently, our results demonstrated that among the cultivars tested the Shaki cultivar is moderately resistant to rosy apple aphid and has the potential to be used in the integrated management of this aphid.
Volume 3, Issue 2 (6-2015)
Abstract
Shahrechay Dam is located at 12th Km of Shahrechay River in Urmia. This study was conducted for a year (Spring to fall, 2007) to identify different species of benthic organisms in the dam. Considering the relevant topographic status like the local depth and water speed, 6 sampling stations were chosen and sampling was done in shallow locations of the river by means of superficial method. In this study, 2 phylums, 2 orders, 13 families and 21 species of benthic organisms were identified in Shahrechay Dam Lake. The results indicated that the highest species diversity belonged to Ecdyonuridae family (Eperous Genus). In terms of frequency, it belonged to Tibuficidae (Tubifex Genus), with 43%, 23%, and 11% ratios for spring, summer, and fall, respectively. The final result of the research demonstrated the poverty of lake bed from view of the benthic quantity and density. Therefore, the Shahrechay Dam was not a suitable candidate to develop fishery’s purposes, especially releasing and growing Cyprinidae fishes and other benthos-feeder aquatics.
Volume 3, Issue 3 (9-2014)
Abstract
The ladybird beetle, Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae) is one of the most important natural enemies of the common pistachio psylla, Agonoscena pistaciae Burckhardt and Lauterer (Hemiptera: Psyllidae). The effects of hexaflumuron and spirodiclofen were investigated on development and carbohydrates and total lipid contents of 4th instar larvae of H. variegata. The insecticides had significant effects on the mortality of eggs, but no significant effects on mortality of larvae or pupae. Hexaflumuron significantly increased the length of development of eggs (2.89 days) and first instar larvae (3.28 days), but had no significant effects on other instars or pupae. Spirodiclofen had no significant effects on developmental stages of H. variegata. Glycogen content was significantly reduced by spirodiclofen (17.42 mg/g fresh body weight) and hexaflumuron (16.07 mg/g fresh body weight). Trehalose content in hexaflumuron (1.89 mg/g fresh body weight) and spirodiclofen-treated larvae (2.02 mg/g fresh body weight) was significantly lower than control (8.01 mg/g fresh body weight). Glucose content in spirodiclofen-treated larvae (0.96 mg/g fresh body weight) was significantly higher than in hexaflumuron-treated larvae (0.24 mg/g fresh body weight) and control (0.15 mg/g fresh body weight). Significant reduction in the amount of lipid was observed in spirodiclofen-treated larvae (5.29 mg/g fresh body weight), but not in hexaflumuron-treated larvae (7.11 mg/g fresh body weight). These results suggest that substantial physiological events in the life of larvae are affected in response to the action of the tested insecticides.
Volume 3, Issue 3 (9-2015)
Abstract
The main diatomic structure-forming species of the Zayandehrud Reservoir was investigated by collecting samples from the surface, five, seven and 10 m depths from January 2011 to October 2012 along four linear transects. Asterionella formosa Hassall, Cyclotella ocellata Pantocsek and Fragilaria crotonensis Kitton were revealed as the three structure-forming species among diatomic algae in the reservoir. The number of these diatomic cells increased from the reservoir banks to its central areas, but their abundance was non-uniformly distributed at the 10-meter water column at different sites, except for C. ocellata that showed a practically uniform distribution at the peak of its maximum growth. Overall, the frequency and cover of these structure-forming diatoms changed under the influence of different abiotic variables such as electrical conductivity (EC) and nitrate (NO3-N).
Volume 3, Issue 4 (12-2023)
Abstract
What is called language? In the history of Western philosophy, we have different answers to this question. However, according to Wittgenstein and Gadamer, these different answers are basically similar, and both criticize this basic approach. Gadamer refers to the history of Western philosophy as the history of forgetfulness of language. But he regards Augustine as an exception in this history; for Gadamer, Augustine has appreciated the central status of language and the vital relation between language and thought through his idea of the inner word. However, Wittgenstein introduces Augustine as the main agent of the basic approach of Western philosophy to language, raising his criticisms of this basic approach by objecting to Augustine's claims. In this article, I review these two different interpretations and think about the possibility of making an affinity and compromise between Gadamer's narration of Augustine's idea of the inner word and Wittgenstein's philosophy of language.
Volume 4, Issue 2 (6-2015)
Abstract
Spotted Amber Ladybird, Hippodamia variegata (Goeze, 1777) (Coleoptera: Coccinellidae) is an important predator of aphids and some other insect pests. Since shape and size variation may affect biological characteristics of an insect, multivariate analysis of shape variations in four geographically isolated populations of H. variegata (Isfahan, Shahrekord, Shiraz, Yasuj) was performed based on eight landmarks of hind wing. According to the analysis, significant difference in weight matrices (as shape variable) was detected. The cluster analysis separated Isfahan population from other populations. According to ANOVA, we found significant difference in centroid size (as size variable), so that the two populations, Isfahan and Shahrekord, had larger wings than the two other populations. Distribution of 80 individuals based on partial warps on the relative warp axis placed Isfahan population in a separate group while the others had overlap and irregular distribution.
Volume 4, Issue 4 (12-2022)
Abstract
An analysis of the state of Iran's water resources shows that hydro-political challenges have shifted from the national scale to the sub-national scale (at the catchment level) and the conflict of interests of users has led to a contradiction in the approach of agents, especially in times of drought. Meanwhile, Karkheh catchment in Khuzestan feeds by Kashkan river in Lorestan province. On the other hand, climate change and Kashkan floods have often been associated with losses. The basic agricultural livelihood of Delfan city and the prevention of floods have made the construction of Gaushmar dam on Kashkan inevitable. The construction of this dam has reduced the volume of water entering the downstream cities of the dam and the Karkheh catchment in Khuzestan, especially during dry seasons. The construction of this dam has led to the conflict of interests of the actors and the emergence of hydro-political challenges on a subsidence scale. The present article is applied and the methodology of the text is explanatory-analytic. The data and information required for the research were collected by library and field methods (interview). The result of the research showed that with the construction of Gaushmar Dam, hydro-political relations within the province (Lorestan) and extra-provincial relations between Khuzestan and Lorestan provinces have been brought hydro-political tension. The adaptation of these conflict of interests eventually led to a reduction in the height of the dam and the volume of water stored behind the dam due to the authorities’ policies.
Volume 5, Issue 1 (5-2024)
Abstract
Aims: Localization of development agency based on unique civilizational-cultural characteristics is one of the concerns and challenges facing urban planners in policy making in Iran. The purpose of this study is to extract and analyze those factors of urban morphology in local studies that have been evaluated as effective on social vulnerability in order to reach a clear definition of the dimensions, components and elements of each of them. Methods: Based on the purpose, this research is applied-developmental, and with a quantitative approach, meta-analysis method has been used to extract the influential criteria and components of urban morphology on social vulnerability. Findings: results show that urban morphology is influenced by the four aspects of: urban economy, transportation management and urban logistics, macro policies of horizontal and vertical development of the city and the urbanization paradigm. Social damage caused by urban form affected by land use management, roads geometry, type of texture in terms of wear and tear, geometry of filled and empty masses and creation of voids, transparency and readability of urban texture, vitality, accessibility and lighting of roads at night, the degree of realization of spatial justice It is for all sections of society and safety in the urban space during natural hazards such as floods and earthquakes. Conclusion: The main approaches to the studies of the dimensions and components of urban morphology are physical, local-climatic, environmental perception and behavioral sciences, historical and geographical, economic-political, social sciences, humanities and cultural-contextual dimensions.