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Showing 130 results for Ali Reza


Volume 0, Issue 1 (5-2011)
Abstract

Species diversity is an index for sustainability of rangeland ecosystems. We studied the effect of environmental factors (soil properties and aspects) on plant species diversity in Zagros mountainous rangelands (vegetation type: Festuca ovina-Astragalus parrowianus) in the west of Hamadan in March–July 2009. For this purpose, four aspects were defined in the study area. Vegetation types were studied by physiognomic-floristic method in the field. The factors of vegetation were measured by transects using a systematic-randomized method. Five transects (100 m) and five plots along each transect were used. One soil sample (composition, 0–40 cm) in each plot was collected by a randomized method and assessed the following factors: pH, OM, N, EC, P, K and texture in the laboratory. The multiple regression method was used to investigate the relationship between species diversity (dependent variables) and soil and topographical factors (independent variables). Results showed that soil characteristics and aspects had significant effects on diversity in which north, east and west aspects as well OM, N, EC and clay were the most prominent factors influencing diversity.

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 1, Issue 1 (3-2013)
Abstract

Study area is located in West of Iran with relatively rough topography. Lithologic units in the region belong from Jurassic and Cretaccous till recent era. The study area of the Alvand mountain region is related to the tectonic zone of the Sanandaj-Sirjan region and the area dominant neo-tectonic regime appears to be compressional-extensional type. One of the identification tools to find out the existence of recent neotectonic activities is tectonic geomorphology evaluation. In this study, we tried to measure the required parameters using topographic maps with scales of 1:50000 utilizing AutoCAD software. In order to identifying the morphologic landform anomalies we use asymmetry factor, transverse topographic symmetry factor and mountain-front sinuosity index. The neotectonic activity of the study area investigated by considering geologic, seismic and remote sensing evidences and with establishing relationship between these evidences and morphologic landforms. Results indicated that tilting occurred around NW-SE axis. There is a remarkable correlation between active mountain front, fault and cleavage identified (from satellite images) and position of earthquake epicenters of study area. Hence all of these evidence indicating the activity of the study area from neotectonic and instability of sub watersheds point of view.

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.

Volume 1, Issue 2 (12-2015)
Abstract

From 2009 to 2012, 16 species of Curculionidae (Coleoptera) from the subfamily Lixinae were collected on 17 species of food plants in Iranian rangelands. Identified species belong to seven genera in the tribes Lixini and Cleonini. The host plants from which they were collected were in the families Asteraceae, Fabaceae, Apiaceae, Campanulaceae, Brassicaceae and Zygophyllaceae. Of the 16 species that we captured, two (Lixus subfarinosus Desbrochers, 1893 and Larinus remissus Faust, 1889) represent the first records from Iran. These new data also extend the known ranges of several species (Larinus fucatus Faust, 1894, Larinus grisescens Gyllenhal, 1835, Microlarinus rhinocylloides Hochhuth, 1847 and Bangasternus planifrons (Brulle, 1832) in Iran. The distribution of beetles and their associated host plants are presented and ecological notes on each species are provided.

Volume 2, Issue 1 (3-2013)
Abstract

Soil-dwelling mites and among them Gamasina (Acari, Mesostigmata) are widely distributed in soils, rich in species and have great ecological significance in the respective ecosystems. A survey was conducted to study Laelapidae (Mesostigmata) mites in Ahwaz (Khuzestan province), Iran during 2010-2012. Samples were taken from soil and litters and then mites extracted using Berlese funnel, cleared in lactic acid and mounted in Hoyer's medium. Among some species of this family, Gaeolaelaps jondishapouri n. sp., collected from soil is described and illustrated. G. jondishapouri n. sp. is characterized by dorsal shield with 39 pairs of setae (including Px2-3), r6 and R1-6 being off dorsal shield on soft lateral cuticle; posterior part of dorsal shield with abrupt contraction between S4 and S5 setae; st1 on weakly sclerotized pre-sternal area out of sternal shield, iv1-2 slit-like. A key to the adult females of the species of Gaeolaelaps with abrupt constriction in dorsal shield (Karg’s angusta species group) is provided.

Volume 2, Issue 3 (9-2013)
Abstract

The carob moth is one of the most devastating pests of pomegranate and some other products. Various pest control measures have been undertaken in order to control this pest but none of them has been successful so far. In the current study the effects of cereal seed proteinaceous extracts including triticale and three wheat cultivars (MV17, Aflak, and Zare) have been studied on α-amylase and protease activity of salivary glands of this insect.Initial screening showed 38, 44, 28 and 76% inhibitory effect for triticlae, MV-17, Aflak, and Zare cereal seed extracts respectively on α-amylase activity. Further studies were performed with Zare wheat cultivar using various concentrations including 13, 6.5, 3.25, 1.625 and 0.8125 µg protein on the enzyme activity and results showed that they inhibited the enzyme activity by 76, 75, 68, 60, and 42%, respectively. Gel assays confirmed the spectrophotometric data i.e the effect of the seed extract on the enzyme was dose dependant. The same trend was observed when seed extracts were tested against proteinase activity. These data suggest that plants produce different proteins with different specificity toward herbivores digestive enzymes some of which could be used for insect control in IPM program.

Volume 2, Issue 3 (8-2014)
Abstract

Qazieh is comic literary style, which was created by Hedayat in his book “Vagh Vagh Sahab”. Beside its application in comic, Qazieh has not been recognized and followed strongly yet. In Qazieh, we confront with Naghizeh style, but features of language, form and content, make it outstanding. Two aspects of Qazieh that bold its prominence are: First confronting poem in a folksy style, and demolishing rhythm and intentionally. In addition, criticizing the hidden social, cultural, and literal problems of the society makes it unique. This essay re-analyzes Qazieh in Vagh Vagh Sahab, and indicates the methods that Hedayat uses in creating Qazieh.

Volume 3, Issue 1 (3-2014)
Abstract

A survey of cereal fields of Khuzestan province during 2008-2011 revealed that cereal cyst nematodes (CCNs) are widely distributed in this region. The CCNs were present in 37 and 35% of the 200 samples collected from wheat and barley fields respectively. The species were identified as Heterodera avenae type B and H. filipjevi the morphological and morphometric identifications of which were confirmed by rRNA-ITS RFLP. Population density of CCNs ranged from 2 to 103 cysts (mean 18)/100 g of dried soil with an average of 395 (0-3400) J2 and eggs in wheat samples. Whilst the number of cysts in barley samples were counted 3-71 cysts (mean 11) /100 g soil, the J2 and eggs averaged 166 (0-900). The lowest and the highest rates of infestation (8 and 83%) were observed in the regions of Ahvaz and Behbahan respectively. The number of J2 and eggs of CCNs in some regions were greater than the damage threshold level considered for CCNs and it is likely they could cause economic yield loss in these regions.  

Volume 3, Issue 2 (6-2014)
Abstract

Essential oils are volatile mixtures of hydrocarbons with diverse functional groups. In the current study the effect of essential oils from five medicinal plants including Zataria multiflora and Nepeta cataria (Lamiaceae), Tagetes minuta and Artemisia sieberi (Asteraceae), and Trachyspermum ammi (Apiaceae) were analyzed using GC-mass spectrometry. The toxicity of these plant essential oils against the adult stage of the cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae) was studied using a fumigant assay.GC/Mass analysis revealed that the main essential oils varied between species. The most abundant components in N. cataria, Z. multiflora, T. ammi, T. minuta and A. sieberi were 4a-α, 7-β, 7a-α-nepetalactone (76.8%), carvacrol (62.1%), γ-terpinene (27.1%), limonene (13.0%) and artemisia ketone (48.0%) respectively. The fumigant assays showed that all of these essential oils were toxic to B.brassicae in a dose-dependent manner. The essential oils of N. cataria at 126, 63, 31, 16, 8, and 3 μl L-1 air caused 94, 76, 52, 46, 36, and 24% mortality within 24 hours, respectively. The same trend was seen when essential oils of the other plants were tested against B. brassicae. These plant essential oils have great potential to be used in integrated pest management especially in greenhouses or other closed systems.

Volume 3, Issue 2 (Summer 2019)
Abstract

In current research, Pseudomonas putida @ Chitosan hybrid biosorbent capability for U(VI) biosorption in a fixed bed column was investigated. The results showed that the increase in inlet concentration from 50 to 200 mg/L increased the biosorption capacity from 188.75 to 429.28 mg/g. In the column system, the sorption capacity was higher than that of the batch system because fixed bed column make best use of the inlet concentration difference as sorption driving force. Decrease in inlet flow rate through increase in the residence time for better diffusion or interaction as well as greater access to binding sites for uranium ions caused an improvement in column performance. Decline in the biosorption capacity due to increase in the inlet flow rate demonstrated that intraparticle diffusion was the rate-controlling step. With decreasing in the sorbent particle size from 1.5 to 1 mm, a significant increase in the biosorption capacity from 179.02 to 296.87 mg/g was achieved. FTIR and potentiometric titration confirmed that while –NH3+ was the dominant functional group in the chitosan, –NH3+, –NH3, –OH, –COOH were responsible for the hybrid biosorbent. In conclusion, the present study indicated that Pseudomonas putida @ Chitosan could be a suitable biosorbent for U(VI) biosorption from aqueous solution in the continuous system.

Volume 5, Issue 2 (6-2016)
Abstract

The elm leaf beetle, Xanthogalerucella luteola (Muller) (Col.: Chrysomelidae) is a serious pest of elm trees and it has been distributed all over the world. The current study was undertaken to investigate the inhibitory effects of protein extracts of three weed seeds including datura Datura stramonium L., amaranth Amaranthus retroflexus L. and wild oat Avena fatua L. against X. luteola α-amylase using spectrophotometric assay as well as in gel assays. The effects of five concentrations of each seed proteinaceous extracts were tested on α-amylase activity of the larval gut. The results showed a dose dependent manner in inhibition of the insect enzyme. At the highest concentration of protein extracts (12 μg protein) of all three seed extracts including amaranth, wild oat and datura, the inhibition was 71, 79 and 31%, respectively. Whilst, at low concentration (0.75 μg protein), the inhibition observed was 15, 36 and 5%, respectively. Thus, the greatest inhibition percentage was obtained when proteinaceous extract of wild oat seed was used. These results were confirmed when in gel assays were performed. All three seed proteinaceous extracts had an optimum pH inhibition of 6.0. Thus, it is concluded that wild oat seed proteins are potentially good for detailed investigation in order to get a clear picture of its active compound/s and its structure-function relationship.    

Volume 5, Issue 2 (Summer 2021)
Abstract

Research subject: In this study, the occurrence of flooding due to the accumulation of sediment in the downcomer area, which led to an excessive increase in liquid on the upper trays of the distillation column was investigated in a refinery.
Research approach: Vacuum pressure in the upper area of the column, boiler feed water flow from the inlet to the condenser and the discharge of the net product as three very important and effective operational parameters in controlling the severity of the flooding phenomena and the amount of coking value as an important laboratory parameter to reduce the volume of inlet sediments entering the distillation column. Data and results of changes made on each of these three operational parameters showed their effectiveness in controlling the severity of the flooding phenomena.
Main results: In order to control and reduce the problems caused by the simultaneous flooding phenomena around the vacuum pump, the boiler feed water flow of the inlet to the condenser and the flow of the net output product were proportionally increased until the operating conditions of the distillation column are normalized. In this study, how to control the flooding phenomena and reduce the adverse effects due to the accumulation of sediments in the downcomer area of tray No. 22 and above was investigated.
To overcome these problems, first the vacuum pump rotation speed was increased from 850 rpm to 1250 rpm and the boiler feed water inlet to the condenser from 1.95 m3/hr to 3.2 m3/hr was increased. On the other hand, in order to prevent contamination of the pure product, the net output product flow rate also increased from 925 kg/hr to 2300 kg/hr. Also, with regular and accurate control of the coking value index as a very important laboratory parameter, the volume of coke sediments in the coal tar feed entering the distillation column was reduced from 37.5% by weight to 18.4% in a 30-day period after centrifugation.
Ali Reza Asadi,
Volume 5, Issue 17 (Spring 2012)
Abstract

This article continues the unfinished discussion of Tzvetan Todorov on the classification of ‘unreal literature’ in the West by expanding his idea about surrealist story as a genre. After defining the term surrealist story and its theory, the authors, drawing on the hypothesis that surrealism is an ancient phenomenon, analyze the components and atmosphere of a selection of mystical anecdotes. The results indicate that the surreal works in the East and the West, from the ancient times, have been grounded on similar theories and comparable elements.

Volume 6, Issue 4 (2-2017)
Abstract

Identifying the necessary infrastructures for an effective management of knowledge and making innovations in organizations are of the paramount importance. In previous investigations, infrastructures have been studied in isolation from other factors, but it has been tried in this research to survey and analyze the direct and indirect impact of the climate and organizational structure on innovation performance considering the mediation of knowledge management and social interaction, through a comprehensive model. Interaction in affecting leadership style & organizational climate on knowledge management also are reviewed. This study has been done using sample of 140 selling and marketing unit employers of the shuttle corporation in Tehran. This research is descriptive- survey and questionnaire used for data collection. Result showed that knowledge management and social reaction are not mediating. Effects of organizational structure on social interaction and organizational climate on knowledge management, social interaction on innovative performance are positive and meaningful, but other hypothesis were rejected.

Volume 7, Issue 1 (5-2015)
Abstract

The aim of this article is to review the process of plan changes from rectangular shapes to square, and the reasons for these changes through the Achaemenid dynasty. The innovation of using square plans in the second stage of Achaemenid architecture progressed with its developed style that fatherly left influence on domes construction in Parthian architecture. The ideology of “Darius The Great” and the impact of affiliated nations on his intellect were the reasons, for which the transformation of pre - Achaemenid rectangular to square plans was occurred. The cited phenomenon was studied to be the result of Greek’s cultural impression, regarding the use of numbers and figures in plans. Square plans stepped into Persian architecture as the perfect shapes with respect to Pythagorean philosophy and beliefs of some intellectuals, such as Plato. Square plans were, moreover, adapted to create a new style of architecture; since, they were the bases on which domes were constructed. 

Volume 7, Issue 1 (Winter 2021)
Abstract

Background: Calf scours (diarrhea) in unweaned calves play a major role in economic losses of animal farming industry worldwide. The present study was conducted to investigate and interpret the presence of BRV, BVDV, and Escherichia coli K99 by molecular and serological approaches simultaneously.
Materials & Methods: A total of 73 E. coli-negative diarrheic fecal samples were collected from one-week to less than one-month-old calves of Holstein dairy cattle herds of some provinces of Iran during autumn and winter. The samples were directed to antigen detection by ELISA (Enzyme Linked ImmunoSorbent Assay), RNA extraction by semi-manual approach, and cDNA synthesis for PCR amplification.
Findings: Out of 73 calves’ diarrheic  fecal samples, 28 (38.3%) and 1 (1.36%) were positive for BRV and BVDR by ELISA, respectively. However, 31 (42.4%) samples were positive for BRV and non for BVDV by RT-PCR. The Kappa coefficient showed significant differences in BRV and BVDR detection between ELISA and RT-PCR methods. The distribution of the BRV-positive samples among bovine diarrheic calves was 80, 52.6, and 50% in Eslamshahr, Qazvin, and Hamedan, respectively.
Conclusion: ELISA and RT-PCR indicated high prevalence rate of BRV in autumn and winter, respectively. The present study results showed that positive cases detected by RT-PCR were more than those detected by ELISA. Further studies are needed to achieve a comprehensive preventive and therapeutic strategy to address  diarrhea bovine pathogens.

Volume 7, Issue 3 (7-2018)
Abstract

The egg parasitoids of the genus Trichogramma have become one of the most important economic insects, for they are widely used in biological control of Lepidopteran key pests. For that reason, all aspects of their mass production including diapause have been considered over the last few years. In this study, the effect of host quality on the diapause induction of sexual and asexual T. brassicae Bezdenko (Hym: Trichogrammatidae) have been investigated at two temperatures. Maternal generation developed at two distinct temperatures (14 and 20 °C) and they oviposited on four different qualities of Ephestia kuehniella Zeller (Lep: Pyralidae) eggs including fresh eggs, frozen eggs, host eggs with developing embryo and low quality eggs. Data analysis revealed significant influence of temperature and host quality on diapause induction in both sexual and asexual strains. Maximum diapause happened in host eggs with developing embryo even though they were in fetal development. A higher level of diapause was observed in T. brassicae whose maternal generation had developed at 20 °C. The diapause induction in asexual T. brassicae was less than sexual wasps. The results imply that Wolbachia causes a disturbance in the diapause process. The outcomes of this study, which are new, indicate the complexity of diapause and the importance of factors such as host quality which have received less attention in diapause induction. 

Volume 7, Issue 4 (1-2008)
Abstract

The development in financial and banking sectors is an integral part of economic growth and development. The experiences of many developing countries show that reform driven policy in finance and banking system enhances economic prosperity and removes the macro investment impediment. This Paper evaluates the impact of Linearization policies (or financial restriction) and also changes in real interest rate on deposit and credit of financial sector development in Iran, over the period 1969-2003. The results show that there is a significant and negative relationship between restriction (and reserves control) and financial development. Also, there is significant relationship between changes in banking real interest rate (credit and deposit) and financial development. While the increase in real interest rate on informal markets leads to demand transfer from informal market to formal market and consequently towards the expansion of financial market in Iran. Therefore, low real interest rate, with regard to other policy considerations, would cause increase in potential investment and will improve the proper use of resources in the economy.

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