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Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract

Cette recherche, qui s’inspire particulièrement du « nudge », une approche innovante en stratégie comportementale, ainsi que de la sémiotique tensive, trouve sa motivation dans les incitations à consommer moins d’énergie. Tout au long de cette étude, nous cherchons à répondre à la question fondamentale de savoir si, en matière d'écologie, les « nudges » peuvent encourager les individus à adopter des modes de vie plus respectueux de l'environnement en modifiant les discours et en faisant ressurgir des situations éthiques oubliées. L’objectif de cette étude est de comprendre comment l'univers du discours est lié aux pratiques de vie et de fournir des solutions simples et pratiques en exploitant le pouvoir du langage et en analysant l'impact du discours indirect sur les mentalités, dans le but de guider les individus vers des choix énergétiques optimaux pour la création d'une ville durable. Étant donné que cette recherche est analytique, la méthode de présentation adoptée repose sur une étude de cas. Dans cette approche, nous avons commencé notre analyse par une description théorique de notre exemple choisi, puis l’avons analysé à travers les approches sémiotiques et la structure tensive. Les résultats des analyses ont démontré que l'approche du nudge peut créer une dynamique éthique, encourageant les individus à s'organiser pour contribuer à une meilleure forme de vie. En orientant subtilement les choix sans contrainte, cette méthode favorise des comportements responsables et solidaires, tout en renforçant la prise de conscience collective.

Volume 0, Issue 0 (ARTICLES IN PRESS 2024)
Abstract

This study aimed to increase the vase life of cut rose flowers by improving the regulation of Programmed Cell Death (PCD). Experiments were carried out on cut rose (Rosa hybrida cv. Dolce vita+) flowers under either physical treatment of Static Magnetic Field (SMF; 15 and 25 mT) for 3 hours, or chemical treatments of silver nano particle (Nano-Ag; 5 and 10 ppm), 6-Benzyladenine (BA; 25 and 50 mg L-1), 1% sucrose, and combinations of 5 and 10 ppm nano-Ag with 3 and 6% sucrose. Results showed that a 15 mT-SMF significantly increased vase life up to 25 days, compared to the controls and to all chemical treatments. Among the chemicals, 5 ppm Nano-Ag and 1% (w/v) sucrose increased vase life to 23 and 18 days, respectively. The smallest decline in fresh weight was observed in the 15 mT-SMF physical treatment. Markedly, the 15 mT-SMF treatment led to the least reduction in Chlorophyll (Chl) content. On the 17th day of the applied different treatments, both Water Uptake (WU) and Relative Fresh Weight (RFW) showed an inverse significant relationship with PCD in cut rose flowers, verifying there markable delayed PCD which is favored the market. As a whole, the most effective induced treatments (15 mT-SMF, 5 ppm Nano-Ag, and 1% Sucrose) are suggested to be promising for enhancing postharvest quality and prolonged vase life of cut rose flowers.


Volume 0, Issue 0 (ARTICLES IN PRESS 2024)
Abstract

The increasing demand for food, especially poultry products, highlights critical challenges to food security. In this context, agricultural entrepreneurship in the poultry sub-sector plays a vital role in addressing these challenges by enhancing food supply and contributing to economic growth and development. This study specifically focuses on fostering entrepreneurship within the poultry industry in Mashhad, emphasizing its pivotal role in Iran's economy and its contribution to food security. Using an exploratory research method along with SWOT and Ordinal Priority Approach (OPA) analysis, 18 factors influencing entrepreneurship in the poultry industry were identified and weighted, leading to the development and ranking of 14 strategies. The results indicate that strategies such as transferring the tasks related to the poultry industry from the government to the private sector (SO) and using the capacities of knowledge-based companies for innovation in the supply of poultry input (WT) have the highest scores. In contrast, strategies such as organizing workshops and training courses (WO) and hiring skilled labore (ST) have lower scores. The findings suggest practical concepts for poultry entrepreneurs, including branding, technology adoption, establishing international animal welfare standards, collaborating with knowledge-based companies, and privatization under government supervision. These strategies can foster regional development by promoting entrepreneurship, which in turn can increase employment, economic growth, and productivity, ensuring a balanced distribution of opportunities and resources

Volume 0, Issue 0 (ARTICLES IN PRESS 2024)
Abstract

Poly- gamma- glutamic acid (γ-PGA) is a natural polymer with diverse applications across multiple industries. However, its use in agriculture is limited due to high production costs. This study aimed to optimize the cost-effective production of γ-PGA through Solid-State Fermentation (SSF) using Bacillus velezensis UTB96, evaluate the concentration and molecular weight of γ-PGA suitable for agricultural applications, particularly in strawberry cultivation, and explore the impact of γ-PGA on extending the shelf-life of strawberry fruits during cold storage. Initially, the production of γ-PGA using SSF with B. velezensis UTB96 was investigated, along with an evaluation of the influence of physicochemical factors on the molecular weight of γ-PGA. Based on the results, three different molecular weights of γ-PGA were identified: 1156.43 kDa, 734.38 kDa, and 296.55 kDa. These were selected for greenhouse trials to assess their effectiveness in controlling gray mold on strawberry plants. The results showed that by utilizing agricultural wastes, including sesame flour, wheat straw, and banana peel in SSF methodology, γ-PGA could be produced at a rate of 70 g/kg of dry weight of the culture medium. Analyzing the impact of γ-PGA on reducing gray mold revealed that this compound could enhance the plant's defense. A significant increase in the activity of ascorbate peroxidase and phenylalanine ammonia-lyase (PAL) enzymes was observed, along with the production of polyphenolic compounds such as ellagic acid. Consequently, these mechanisms improved the plant's flexibility and tolerance to the fungus, helping to maintain the quality of the fruits during cold storage.


 

Volume 0, Issue 0 (in press 2024)
Abstract

The use of pozzolans is very necessary and inseparable for the sustainable development and better performance of the concrete industry. In the production of concrete, the combination of iron powder, fly ash, metakaolin and limestone powder under the name of fracking is used as materials and substitutes for cement in different percentages. The compressive strength of this concrete is higher than normal concrete. This type of concrete is a very new concrete that few tests have been done on it in the world, so there is not lot of information available about it. According to the studies, the most important features of this concrete are the use of iron waste, reduction of air and environmental pollution, cost savings and higher compressive strength than ordinary concrete. In this research, in order to protect the environment and reduce environmental pollution, fracking has been used as a relative substitute for cement. After obtaining the appropriate proportions, the frac mixture with percentages of 0, 3, 6, and 9 was considered as a substitute for cement. There were 8 tests in this research, 4 tests of the first category were carried out with the mentioned percentages of frac and 0% of steel fibers, but in the 4 tests of the second category, the volume of 1% of steel fibers was considered in the mixture. In this research, a total of 16 concrete samples were made, of which 8 of the first batch were used for pre-heating tests and 8 of the second batch were used to collect the results and performance of the concrete after heating. took After making the concrete samples and performing the necessary processes, the concrete samples were molded and placed on the vibrating table in order to make them denser and prevent voids in the concrete. After vibrating for a sufficient time, the samples were placed in the open space for 24 hours and then placed in the water basin for the processing process. A group of samples was taken out of the pond after 7 days to perform compressive and tensile strength tests (at the age of 7 days, due to the freshness of the concrete, exposure to high heat was not done) . After 28 days, the second batch was removed from the water and prepared for testing. The tests performed on these samples include compressive strength before and after heating, bending strength before and after heating, ultrasonic before and after heating, and water absorption before and after high heat. To test the performance of the samples after heating, the samples were placed in the furnace at a temperature of 450 degrees Celsius for 60 minutes (one hour) and after one hour, the samples were removed from the furnace and The samples were cooled at a temperature of 24 degrees Celsius. After the cooling of the samples, the tests were conducted on the samples, and the results indicated that the increase in the amount of frac leads to a 16% increase in the compressive strength before heating and improving its mechanical properties compared to ordinary concrete.

Volume 0, Issue 0 (in press 2024)
Abstract

Fire can not only lead to many human and financial losses, but also can cause structures to collapse and destroy them. For this reason, it is necessary and inevitable to protect buildings against fire and conduct more research in the field of better understanding the effects of combining different materials with each other and obtaining materials with greater resistance to fire. Concrete and concrete structures are always used by construction engineers due to their resistance, availability and resilience against fire. Ordinary concrete loses its strength at high temperatures, and the use of unreinforced concrete is not very useful due to its brittleness and weakness in tensile strength. In concrete, the tensile strength is lower than its compressive strength, and for this reason, researchers are trying to increase the resistance to fire and heating by improving the tensile strength of concrete. Reinforcing concrete with rebar is always a solution to increase the tensile strength in concrete parts, one of the most important weaknesses of using rebar in concrete is that the reinforcements form a small part of the concrete cross-section and actually cause the concrete to be inhomogeneous. In this research, double-bent steel fibers have been used to overcome the mentioned weakness and reinforce the concrete. It should be noted that concrete containing steel fibers has favorable compressive and tensile strength due to the high tensile strength of steel fibers. In order to achieve this goal and achieve fiber concrete that has good fire resistance, we defined seven different mixing plans with different percentages of steel fibers and lubricants. Concrete samples were produced using double-bent steel fibers in amounts of 0.5, 1, and 1.2 percent by volume of concrete and superlubricant in 0.5, 1, and 1.3 percent by weight of cement, and then in Cubic molds with dimensions of 10x10x10 cm and cylindrical ones were sampled as standard, and after setting the cement, the 28-day-old concrete samples, after heating and placing inside the electric heater with different temperatures, were divided into two The method of gradual cooling with ambient air and fog spraying (water spraying) is similar to what firefighters do when extinguishing a fire, after measuring the amount of weight loss of the heated samples, the weight loss values ​​were presented in the form of a diagram, then the samples were subjected to tests Compressive strength, tensile strength (Brazilian test) and ultrasonic wave speed (ultrasonic test) were placed, and the results and data of each of them for each mixing design were presented in the form of a diagram after examination and classification, so that the effect of high heat on Concrete containing steel fibers and super-lubricant should be determined. The results clearly showed the improvement of the tensile strength in three volume percentages of fibers by 14.6, 16.8 and 64.5%, respectively, compared to concrete without fibers, and also the compressive strength of concrete after bearing the heat of 250 degrees Celsius and cooling to the fogging method had 44.5, 31.6, and 9.3 percent, respectively, and in the gradual air cooling method, the compressive strength was 43.3, 44.9, and 50 percent, respectively.


 

Volume 0, Issue 0 (Articles accepted for Publication 2024)
Abstract

  Aim and Introduction
Ecological footprint accounting is composed of two metrics, the “demand-side” (ecological footprint) and the “supply-side” (biocapacity). While the ecological footprint calculates the demand for natural assets in global hectares, biocapacity symbolizes the supply capacity of nature to meet this demand with the same unit of measurement. Ecological deficit also shows the difference between ecological footprint and biological capacity. Globally, the degree of ecological deficits continued to expand over the last decade due to the increase in EF and reduction in biocapacity, which is caused by the following: increasing consumption of fossil fuel energy, overexploitation of natural resources, unsustainable production methods, and economic activities.
Iran is one of the countries that has a weak environmental performance. According to the Global Footprint Network, Iran's ecological footprint exceeded 333% of its biological capacity in 2022. Iran's ecological deficit, which was - 0.55 global per capita hectares in 1961, has increased by 554% to 2.50 global per capita hectares in 2022, and the destruction and pollution of the environment in Iran have reached unsustainable levels. Therefore, the analysis of the determinants of environmental quality can provide insights into the design of appropriate environmental policies in Iran. 
In this regard, the environmental effects of dependence on crude oil have attracted considerable attention. Crude oil is an important and largest source of energy, especially for developing countries such as Iran. It is a fossil-based fuel and a major source of carbon emissions in the world. Hence, many studies have linked oil price shocks to environment quality. In contrast to oil-importing economies, where oil price increases encourage a shift to cheaper and cleaner alternative energy sources, the environmental policy issue in oil-exporting countries is entirely different. Indeed, a fall in oil prices may be associated with a decreased investment in environmentally friendly energy sources. By comparison, an increase in oil prices revealed a reluctance to diversify the economy away from its reliance on non-eco-friendly fossil fuel energy.
Based on the explanations above, the main purpose of this article is to investigate the asymmetric impact of scaled oil price impulses on the environmental Load Capacity Factor (LCF) in Iran using the Non-linear Autoregressive Distributed Lag (MATNARDL) approach. The paper intends to make the following contributions to the literature. Firstly, this article is the first to look into the effect of oil prices on the LCF in Iran by applying asymmetric methodologies. Secondly, it is the first study with a reverse load capacity factor as an environmental sustainability indicator. Thirdly, this paper applied the advanced and newly developed MATNARDL for asymmetric and nonlinear analysis to provide a more robust result that exhibits relevant policy implications. Finally, this innovative study investigated the effects of oil prices on the LCF in Iran between 1961 and 2022 in the framework of the LCC hypothesis.
Methodology
The study compiles annual data for the period 1961-2022 for Iran from three different sources. According to Statista, OP represents average annual OPEC crude oil price (in US dollars per barrel). The data are obtained from the World Bank, GDP per capita, (constant 2015 dollars), Energy Consumption (EC) as kg of oil equivalent per capita, Ecological Footprint (per capita, gha) and LCF (the load capacity factor) are obtained from Global Footprint Network. Because the LCF includes biocapacity in the numerator and EF in the denominator, it allows for simultaneous environmental assessment on the supply and demand sides. A higher LCF indicates a better environment. The current paper's economic functions are illustrated in Equations (1):

LnLCFt=fLnOPt, LnGDPt,LnGDPt2,LnECt,εt                                               (1)
The main objective of this study is to examine the major, medium and minimal scales of positive and negative changes in oil price on the environmental quality index in Iran. For this purpose, the MATNARDL is used as an estimator to examine the effect of minor to major adverse shocks and minor to major positive surprises in the explanatory variable on the explained variable.
Findings
The bounds cointegration test results confirm a long-term relationship in the asymmetric model. The estimation of the model has been performed by categorizing the positive and negative impulses of the oil price in three small (quantiles less than the τ30 threshold), medium (quantiles between the τ30 and τ70 thresholds), and large (quantiles greater than the τ70 threshold) scales in the form of MATNARDL approach. The results indicate that in the long term, small scale of positive (negative) oil price impulses had a positive (negative) and significant effect on the load capacity factor; while these impulses have a negative effect on the load capacity factor in the long term in both medium and large scales. Based on other results, energy consumption has a negative and significant effect on the load capacity coefficient, and the environmental hypothesis of the load capacity curve (LLC) in Iran is confirmed.
Discussion and Conclusion
Based on the obtained results, it can be said that the effect of oil price on the load capacity factor in Iran is asymmetric. Among positive impulses, only with increase in small scale of oil price, we can see an increase in load capacity factor and environmental sustainability in the country. Moreover, the positive impulses of the oil price on both medium and large scales lead to the increase of environmental instability by prioritizing economic achievements and activities over environmental issues
  


Volume 0, Issue 2 (8-2011)
Abstract

The relationship between topography, soil factors, and distribution of ecological vegetation groups in the Nodoushan arid rangelands of Yazd province (Iran) was investigated. The present species were recorded in each vegetation group using a randomized-systematic sampling method. Plant cover and density were estimated quantitatively using the transect and quadrate methods, and the two-way indicator species analysis (TWINSPAN), after which vegetation was classified into different groups. Soil samples were taken from 0–30 cm in each quadrat. In each vegetation group, 20 environmental variables including altitude, slope, aspect, percentage of bare rock, grazing intensity, percentage of gravel, soluble ions (Na+, K+, Mg2+, Ca2+), total nitrogen, organic matter, lime, gypsum, EC, pH, and percentage of sand, silt and clay were measured. Multivariate techniques including detrended correspondence analysis (DCA) were used to analyze the collected data. The results showed that the vegetation distribution was related to elevation, slope, and soil characteristics such as texture, organic matter, gypsum, acidity, lime, and gravity percentage.

Volume 1, Issue 1 (3-2013)
Abstract

Otters at the top of the food chain and feeding largely on fish are likely to be especially vulnerable to the effects of bioaccumulating pollutants. This research reports the first data on mercury levels found in hairs of river otters (Lutra lutra) from Iran. Between June and December 2007, we collected museum and recent collections of river otter hair. These samples were collected from several provinces of three major regions of Iran. The mean of mercury concentration for all samples (recent and museum) was 5.819±1.557 mg/kg with 95% confidence interval for the mean. The concentrations of Total Hg (THg) in hair ranged from 0.293 to 12.382 mg/kg. No significant variation among the sample regions existed. A comparison of THg concentrations between two decades (1986-1996 and 1996-2006) showed that these differences were significant (p

Volume 1, Issue 1 (2-2016)
Abstract

Background: Osteoporosis is one of the most common metabolic bone diseases. The purpose of this study is to investigate the effect of a walking education program based on the health belief model (HBM) on osteoporosis among women. Material and Methods: In this quasi-experimental research design, 120 patients (60 experimental and 60 control),who were registered with the health centers in Fasa City of Fars Province, Iran, participated in the study in 2014. A questionnaire consisting of demographic information and HBM constructs was used at pre-intervention, immediately after their intervention, and then six months later. Bone mineral density (BMD) was recorded at the lumbar spine and femur prior to and six months post-intervention. Data were analyzed using SPSS19' through 'chi-square test, independent t-test, repeated measure ANOVA at a significance level of 0.05. Results: Immediately and six months after the intervention, the experimental group showed increased in knowledge, perceived susceptibility, perceived severity, perceived benefits, perceived barriers perceived, self-efficacy, perceived internal cues to action and walking performance compared to the control group. Six months after the intervention, the value of lumbar spine BMD T-Score in the experimental group increased to 0.127, while in the control group it decreased to -0.043. The value of the hip BMD T Score in the intervention group increased to 0.125 and in contrast, it decreased to-0.028 in the control group. Conclusions: This study showed the increased knowledge and walking behavior regarding walking benefits could improve bone density. Therefore, HBM model can be a basic framework for designing and 'carrying out' educational interventions for women’s osteoporosis.

Volume 1, Issue 1 (Autumn 2017)
Abstract

Oil resistant o-rings on the basis of acrylonitrile butadiene rubber (NBR) reinforced by nanoclay were produced via a traditional industrial method in accordance with aviation standard, AMS 7272. The production of nanocomposites comprised the compounding of nanocomposite with optimum mechanical properties and minimum contents of used carbon black and nanoclay, design and manufacturing of the required mold and finally compression molding of the oring. Mechanical and morphological properties of NBR/nanoclay compounds were optimized by introduction of proper contents of a compatibilizer containing a mixture of resorcinol and hexamethylene tetramine through using a master batch production method. The prepared nanocomposites were characterized using X-ray diffraction (XRD) analysis, curing measurements and tensile test analysis. The XRD analysis showed that the compatibilizer facilitates the intercalation of nanoclay silicate layers with the rubber chains which leads to the increase of their basal spacing. The cure characteristics of the nanocomposites showed a decrease of scorch time and increase the cure rate index with the nanoclay loadings. Furthermore, the minimum scorch time and maximum cure rate index could be achieved through using the appropriate content of compatibilizer. The results exhibit that the nanocomposites containing the compatibilizer have higher mechanical properties especially at higher deformations compared to the corresponding uncompatibilized nanocomposites

Volume 1, Issue 2 (Summer 2008)
Abstract

One of the important problems in Structuralist narratology is the relation between narrative and time and the manifestation of time in narrative.Some philosophers such as Paul Ricour believe that understanding time in an abstract form is very difficult but the action in narrative makes the time objective and concrete.According to Structuralists’ analysis, time, -with causality- is one of the essential components in developing the narrative.In addition, every narrative text has two times:the narrative’s signifier time ( the time it takes a reader to read a narrative text) and the narrative’s signified time ( the time taken up by the events of the narrative).The Structuralists, especially Genette, have posed three issues regarding the time in narrative: 1- Order,i.e.the way the events in the narrative are ordered and presented 2- Duration,i.e.the relation between the length of time of the story and the time of the speech or the signifier of the narrative 3- Frequency,i.e.the number of times an event occurs and the number of times that event is narrated.In addition,at the end of the article, different kinds of relations between the time of occurance of the events in the narrative and the time of their narration by the narrator are examined.

Volume 1, Issue 2 (10-2013)
Abstract

Nizami Ganjavi was a great Masnavi writer of the 6th century (AH.) and one of the founders of Persian poetic fiction. One of the attractions of Nizami’s Masnavi is blessing, litany, and ascensions that are seen in the beginning of each of his verses, which have been highly regarded by his followers due to their beauty and unutterable imagination. The current paper intends to make a comparative study of Nizami’s Khamsa (or five poems) and three Arabic ascensions before it; i.e. Kitab al-Maeraj of Qashiri, Maeraj al Nabi of Ibn Abbas and Al Isra’a va al Maeraj of Ibn Hajar Esghalani and Sayouti that have shown similarities and differences in structure and content. Hence, it is concluded that in spite of distinguishing features, Nizami has been much influenced by the aforementioned works in performing his ascensions. To this end, the literature of Nizami was matched with the evidences acquired from the above ascensions so that similarities become more apparent and obvious.

Volume 1, Issue 3 (9-2013)
Abstract

Mnemiopsis leidyi population activities first were recorded during the coastal observations in 2001 in which its population considerably increased afterward and now sustained the southern Caspian Sea. Maximum summer-autumn M. leidyi abundance was recorded in euphotic layer in 2002 (851±85 ind.m-3) and maximum biomass was in 2001 with 48.1±14.4 g.m-3) while minimum were in aphotic layer. In years 2003 to 2011, M. leidyi abundance and biomass sharply declined to 1-843 ind.m-3 and 0.07-37.7 g.m-3, respectively. The length-frequency distribution of Mnemiopsis showed larval, juveniles and transitional stages that made up 98.6% of the total population. In the southern Caspian Sea, Acartia tonsa was the highest number of mesozooplankton species (36 species) which decreased tenfold after Mnemiopsis invasion during 2001-2010. Fecundity experiments of Mnemiopsis showed the average of 8 eggs. day-1, with a maximum of 35 eggs.day-1which increased with increasing body length. The main food was larger amounts of zooplankton prey such as copepodites and adult of A. tonsa. It seems the sharp decreased of Mnemiopsis abundance could be related the decreasing of ova reproduction; and food ability is the main reasons of M. leidyi sustained in the southern Caspian Sea. The objective of present study was to provide information about parameters influencingthe M. leidyi decreased after initial bloom invasion in the southern Caspian Sea.

Volume 1, Issue 3 (Summer 2023)
Abstract

In this study, we investigated the effectiveness of both single and hybrid systems, incorporating UV photolysis and a Moving Bed Biofilm Reactor (MBBR), for treating synthetic wastewater contaminated with petroleum hydrocarbons. Petroleum hydrocarbons pose significant environmental threats due to their high toxicity, stability, accumulation potential, and resistance to biodegradation. In the hybrid system, the wastewater underwent chemical treatment first and then was introduced into the biological reactor. For the photolysis system, we explored the impacts of different concentrations and various radiation powers of UV-C lamps. Optimal conditions were determined to be a Chemical Oxygen Demand (COD) of 350 mg/L and a radiation power of 80 W. In the MBBR system, various concentrations were introduced into the reactor, achieving a maximum removal efficiency of 85% for an initial COD of 1000 mg/L over 72 hours with a 50% filling capacity. In the hybrid system, we achieved a remarkable hydrocarbon removal efficiency of 99% after 123 hours. Although the operational time of the hybrid system was relatively long, it demonstrated itself as a suitable treatment process compared to other conventional methods for removing these challenging, hard-to-biodegrade compounds.

Volume 1, Issue 4 (12-2013)
Abstract

Vetiver grass is known to survive under diverse soil and water conditions. In order to test its potential of salinity and aridity tolerance ability, the effect of salinity and aridity stress on the growth of the Vetiveria zizanioides was studied by growing plants in arid soils that receiving salinity stress. The experiment was conducted in a greenhouse, arrangement in a completely randomized design using 5 replications. Salinity levels of 4 (as control), 20, 30 and 40 dS m-1; Aridity levels of field capacity irrigation (as control), -6 and -10 bars were applied. There was no significant effect on growth, yield, water content and chlorophyll concentration with 20 dS m-1 salinity level. There was significant effect on Mentioned parameters with 30 and 40 dS m-1 salinity levels. The root and length weight in -6 bar were significantly greater than those in control. The water content and chlorophyll concentration were highest in 40 dS m-1 and -10 bars salinity-aridity. Water content and chlorophyll concentration were lowest in 4 dS m-1 and FC salinity-aridity treatments. Our results suggest that in EC between 20 to 30 dS m-1 with -6 to -10 bars water content Vetiveria zizanioides could be used for soil rehabilitation.

Volume 1, Issue 4 (12-2013)
Abstract

An 84-day feeding trial was carried out onfingerling (4.44 ± 0.06 g) rainbow trout (Oncorhynchusmykiss, Walbaum, 1792) to evaluate the effect of dietary supplementation with a commercial prebiotic GroBiotic®-A (G-A) on the growth, feed efficiency, haematology and immunlogical parameters. Ttreatments containing various inclusions of G-A (0 %, 0.5 %, 1.0 %, 1.5 %, 2.0 %, 2.5 %, and 3.0 %) were added to a commercial fish dietand were fed twice daily at 2-6 % of body weight. The highest weight gain (WG), specific growth rate (SGR) and average daily gain (ADG) were obtained in fish fed the diet containing 2.5 % G-A followed by 3.0 % inclusion (P<0.05). The highest feed efficiency (FE), protein efficiency ratio (PER) and net protein utilization (NPU) were also recorded in the 2.5 % G-A inclusion (P<0.05). Survival was significantly higher (P<0.05) in fish fed with 2 % and 2.5 % G-Asupplement (P<0.05). Although higher Hb, haematocrit, RBC, WBC, MCH, MCHC, MCV, lymphocytes, and neutrophils were observed at all  G-A supplemented diets, the differences among themwerenot significant (P>0.05). On the other hand,significantly higher differencee (P<0.05) in lysozyme and immunoglobulin (IgM) concentrations wereobserved in 2.5% G-A inclusion. The results of this study indicated that 2.5 % G-A inclusionhad a better performance on growth and haematoimmunological parameters in rainbow trout fingerling.
Naseh Abdollahzade, Samad Zare, Ramin Manaffar, Aliraza asem,
Volume 2, Issue 1 (9-2011)
Abstract

Abstract: In recent years, extension of Artemia applications in aquaculture and decreasing of natural resource, lead many of related studies to the distribution of Artemia population and new resource assessment studies. Urmia Lake as one the biggest habitat for Artemia because of ecological variations in the regions in which of its differentiations in cyst biometry and Artemia, moreover some genetic variations suggested to have some several Artemia populations in the Lake. In this project Artemia cyst samples were collected from 5 ecological stations of the Lake Urmia. The cyst hatching and the nauplii breeding up to adult Artemia stage were done according to optimum conditions in laboratory. Growth rate and survival of larva in days of 3, 5, 7, 11, 15, 20 of rearing period were measured in feeding with a complex of Dunaliella tertiolecta and Lanzy PZ for a period of 20 days in 75 and 150 ppt. Data and its statistical analysis revealed that according to previously records the growth rate of the Artemia was influenced by increasing the salinity from 75 to 150 ppt survival and growth rate of Artemia have been influenced by water salinity (P<0.05) but increasing the salinity only in two population of Bari and Eslami led decreasing of survival. The produced cysts in two salinity showed that Artemia population can produce the cysts with different diameter and there were not any statistic correlations between the salinity and populations. The Dandrogarm of population statistic analysis emphasized that according to growth rate and survival parameters and among populations under this test there were 4 different populations of Artemia urmiana in which had interesting differentiations in growth rate and survival. Keywords: Artemia, Survival, Growth rate, Salinity, Urmia Lake.

Volume 2, Issue 1 (4-2002)
Abstract

A time-domain approach is presented to calculate electromagnetic fields inside a large Electromagnetic Pulse (EMP) simulator. This type of EMP simulator is used for studying the effect of electromagnetic pulses on electrical apparatus in various structures such as vehicles, a reoplanes, etc. The simulator consists of three planar transmission lines. To solve the problem, we first model the metallic structure of the simulator as a grid of conducting wires. The numerical solution of the governing electric field integral equation is then obtained using the method of moments in time domain. To demonstrate the accuracy of the model, we consider a typical EMP simulator. The comparison of our results with those obtained experimentally in the literature validates the model introduced in this paper.

Volume 2, Issue 1 (3-2014)
Abstract

This research investigates the vegetation of 4600 ha of Polour semi-steppe rangelands in relation to edaphic and physiographical parameters in Mazandaran province. For this purpose, 23 land units were selected from overlaying slope, aspect and elevation maps using geographic information system (GIS). Within each unit, 3 parallel transects with 100 m length, each containing 10 quadrates (according to vegetation variation) were established. Sampling method was Random systematic. Measured soil properties included texture, organic matter, pH, electrical conductivity, nitrogen, phosphor, and litter. Soil and plant data were analyzed with redundancy analysis and SHAZAM 10 package. RDA analysis suggesting that there is a relatively high correspondence between vegetation and environmental factors that explain 93% of the total variance in data set. RDA results showed that soil slope, aspect, soil texture, acidity, phosphor, and litter were the major environmental factors responsible for variations in vegetation patterns. Furthermore, results also showed that for F .ovina and P .bulbosa, acidity and nitrogen, for A .gossypinus, organic matter and salinity and for D .glomerata, nitrogen have the most important role in plant presence and absence probability.

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