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Showing 15 results for Kheradmand
Volume 1, Issue 1 (3-2012)
Abstract
Abstract The aphid parasitoids, Aphidius colemnai Viereck and A. matricariae (Haliday) (Hymenoptera: Braconidae: Aphidiinae) have high potential as the most effective biological control agents for controlling the cotton aphis Aphis gossypii Glover (Hemiptera: Aphididae). In this investigation, the effect of five constant temperatures (10, 15, 20, 25 and 30 °C) on the reproductive parameters was studied at 65 ±5% relative humidity and a photoperiod of 16L: 8 D hours In this study, the newly laid (one- day old) eggs were reared on third instar nymphs of cotton aphid, and the pupal and adult stages of the parasitoids were recorded daily, until the last individual was found dead. The experiments were carried out with 15 replications at each temperature. The results revealed that the gross fecundity and fertility rates were significantly different at all tested temperatures for both species (P
Volume 2, Issue 2 (6-2017)
Abstract
Background: Addiction is considered as a social disease causes economic loss in family shared financial resources, increase in health care costs, and sexual dysfunctions in sexual relations. Due to the high prevalence rate and reduced age of addiction beginning, this study aimed to evaluate the prevalence rate of comorbidities (psychiatric disorders, liver and neuromuscular diseases) in patients with substance abuse problems.
Methods and Material: In this descriptive study, 200 drug abusers referred to Borzouyeh clinic in Tehran, Iran were selected by convenience sampling method. Data were collected with the help of a questionnaire, liver function tests, and clinical records of the patients during 2010-2016. Data were analyzed through the analysis of Chi-square test at the significance level of P < .05.
Results: Data analysis was performed using chi-square test in SPSS software version 23. The results showed that there was a significant relationship between addiction and liver diseases, psychiatric disorders, and neuromuscular pains (p < .05). According to the results, 44.9% of the patients consuming crack had psychiatric disorders, and also 49.1% of the patients consuming opium had liver diseases. Also, neuromuscular pains were found in drug users (opium, sap, heroin and crack) and not found in hallucinogenic and stimulant drug users.
Conclusions: The correlations between opium and liver diseases, drug users and neuromuscular pains, and also crack using and psychiatric disorders were determined.
Volume 4, Issue 3 (9-2015)
Abstract
A faunestic study on Stigmaeidae and Cryptognathidae families in Lorestan province was carried out during 2012-2013. In this study 18 species were collected and identified, of which Favognathus amygdalus and F. cordylus (Cryptognathidae) were new records for Iranian fauna, also all of the collected species in this study were new records for fauna of Lorestan province. Stigmaeidae with 14 species and Cryptognatidae with four species had the highest and lowest number of identified species, respectively.
Volume 9, Issue 1 (12-2020)
Abstract
The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) is one of the most important pest species, with an extended range of host plants in the world. Use of chemical acaricides is one of the principle ways of controlling this pest. Considering the resistance to acaricides, as well as undesirable effects of chemical compounds, finding a suitable alternative way to control this pest is necessary. In this study sublethal effects of Dayabon®, a herbal extract, were investigated on some biological parameter of T. urticae at 2.140 g/l (LC5), 2.682 g/l (LC10) and 3.526 g/l (LC20). The estimated LC50 for T. urticae adult was 5.950 g/l. When adults were treated with LC10 and LC20 of Dayabon, the oviposition period was significantly reduced compared to LC5. The highest and the lowest fecundity (number of eggs laid per female) were 56.02 offspring/individual in control and 39.11 offspring/individual at LC20 respectively. In addition the net reproductive rate (R0) was decreased as concentration increased. Whereas, intrinsic rate of increase (r) and finite rate of increase (λ) were not affected by Dayabon. Considering the detrimental effects of Dayabon on some biological parameters of T. urticae, it can be concluded that this product can be used to develop targeted interventions aimed at integrated management of T. urticae.
Volume 9, Issue 1 (12-2020)
Abstract
For successful implementation of integrated pest management (IPM) programs, having knowledge on lethal and low-lethal effects of pesticides on natural enemies is necessary. The present study evaluated the low-lethal effect of thiamethoxam on life table parameters of the subsequent generation of the predatory mite, Neoseiulus californicus McGregor (Acari: Phytoseiidae) fed on Tetranychus urticae Koch under laboratory conditions. The low-lethal concentrations LC5, LC10 and LC20 were determined based on a dose-effect assay. The raw data were analyzed based on age-stage two sex life table analysis. Exposure to the low-lethal concentrations of thiamethoxam had no significant effects on developmental time of offspring of treated mites. Compared with control treatment, the oviposition period of treated mites with LC5, LC10 and LC20 decreased significantly. The highest and lowest values of total fecundity were obtained at control (35.3 eggs/female/day) and LC20 (23.6 eggs /female/day), respectively. The net reproductive rate (R0) decreased with increasing dose from LC5 (22.6 offspring) to LC20 (15.0 offspring). The intrinsic rate of increase (r) and finite rate of increase (λ), were not affected by increasing concentrations. The mean generation time (T) decreased significantly at upper dose (LC20 = 13.2 d), compared with control (14.7 d). In consequence, the low-lethal concentration influences of thiamethoxam in combination with N. californicus in order to design management programs of T. urticae are discussed.
Volume 10, Issue 2 (2-2021)
Abstract
The two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) is one of the most important and destructive herbivorous mites in farm and greenhouse that has developed high levels of resistance to many acaricides. In this study, we investigated the effect of sublethal concentrations of hexythiazox at LC10, LC20, and LC30 on the development and reproduction parameters of Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) and its prey T. urticae. The crude data were analyzed based on age-stage, two-sex life table analysis. Hexythiazox (at LC20 and LC30 levels) reduced the oviposition period (9.68, 8.06 days), total lifespan (22.37, 20.88 days), and total fecundity (50.97, 46.21 eggs/female) compared to the control but did not affect those parameters of A. swirskii. The intrinsic rate of increase (r) and finite rate of increase (λ) were not significantly different at tested concentrations, but the net reproductive rate (R0), gross reproductive rate (GRR), and mean generation time (T) reduced significantly. Our study demonstrated lower toxicity of hexythiazox on A. swirskii compared to its prey. It could be concluded that the use of selective acaricides at lower concentrations may be helpful in integrated pest management programs.
Volume 12, Issue 1 (2-2023)
Abstract
The two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) is one of the most important pests of many crops worldwide. Combined tactics for pest management have a significant special effect on reducing pesticide use and maintaining the activity of natural enemies, which is the main objective of IPM programs. The effect of low-lethal concentrations of Eforia (24.7 SC, Syngenta Co.) at LC5, LC15, and LC25 were investigated on biological parameters of Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) under laboratory condition at 25 ± 1 °C, 70 ± 5% RH and 16:8 (L: D) h. The data were analyzed based on a two-sex life table procedure. The results showed that Eforia caused a significant reduction in fecundity (Control: 37.17; LC25: 23.04 eggs/female) and total life span (Control: 42.67 days; LC25: 24.65 days). The net reproductive rate (R0) was 22.31, 20.12, 15.14, and 14.98 eggs/individual, respectively, at control, LC5, LC15, and LC25. The maximum and minimum values for the intrinsic rate of increase (r) were recorded to be 0.17 (Control, LC5, and LC25) and 0.15 (LC15) day-1 for the treated mites. Based on the results, the application of low lethal concentrations of Eforia harms some biological parameters of this predatory mite, and the results of this study showed that Eforia may not be applied for the control of T. urticae pest together with A. swirskii.
Volume 13, Issue 2 (5-2022)
Abstract
Loan words, as one of the consequences of language contacts, can be widely used by native language speakers. The expansion of loanwords varies depending on many linguistic and non-linguistic factors. The present study, based on a descriptive-analytical method, aims to investigate the usage of loanwords in spoken Persian from three different perspectives: semantics, pragmatics, and sociolinguistics. For this purpose, 600 minutes of spoken Persian corpus of Al-Zahra University, including 14000 sentences in Persian for 100 different situations and subjects, used by 240 female speakers and 80 male speakers, have been extracted and studied according to loanwords’ “semantic fields”, “abstraction and non-abstraction”, and “usage frequency” as well as two sociolinguistics variables (“motivation” and “gender” of the speakers). The results of comparing the variety of loanwords and their usage frequency in different semantic fields show that the highest frequency of use belongs to the semantic fields of basic actions and technology, language and speech, and social and political relations. Moreover, research data indicate that loanwords are more related to abstract concepts and phenomena comparing to concrete ones. The research results, from the sociolinguistic view, also reveal that more women than men use loanwords with a common Persian equivalent. “Filling communication gaps in recipient language” and “social, cultural, political and scientific credibility of donor language” are the most important motivations for Persian speakers to use loanwords in their speech.
The usage of loanwords is not limited to a specific context or field of language. Speakers of each language may use different loanwords in their everyday speech, depending on their individual and social needs or motivations. The current study aims to investigate the usage of loanwords in the spoken Persian from three perspectives: semantics, pragmatics, and sociolinguistics.
Thus, the following research questions are raised:
1. Which semantic fields of loanwords have the highest frequencies in spoken Persian?
2. Are loadwords more related to abstract or concrete concepts?
3. Regarding the gender of speakers, which group mostly uses loanwords with a common Persian equivalent?
4. What are the most important motivations for the use of loanwords by Persian speakers?
A) Linguistic and sociological studies about loanwords, including Robins (1964), Sapir (1970) and Haspelmath (2009).
B) Corpus-based studies of Persian language, including Sharafi (2000), Mehryar (2003), Sattari (2009), Ketabi et al. (2010), Kargozari & Tafazzoli (2012), Mohammadi & Abdotajedini (2013).
A small number of the mentioned studies have been devoted to the invetigation of spoken Persian and the majority of researchers have studied loanwords in written literature. Moreover, in those limited number of works on spoken Persian, the reaseachers have expolred controlled data, mostly recorded radio and television programs, which are far from normal speech. Thus, as can be seen, this is the first time that the facts of spoken Persian have been studied in terms of the usage of loanwords.
The corpus of this study, being prepared in the Linguistics Department of Al-Zahra University, is the first and currently the only corpus of natural speech for spoken Persian recorded in various social situations. One of the most important features of this corpus is that, unlike other controlled databases, here the researchers have access to natural speech of native speakers. Since the participants are not aware of this fact that their words are being recorded, the results and findings can reveal facts of nature speech and consequently are less biased. There is no need to mention that all privacy concerns have been observed during data collection.
List 1: loan words of the corpus
List 2: Derived, compound, and Derived-compound words containing a non-Persian element
Men mostly use those loanwords which are often common words in Persian and don’t seem strange, and a small percentage of their loanwords are non-common and have a typical Persian equivalence; However, this percentage is higher for female participants. In other words, in most cases, men’s purpose of using loanwords is to “fill communication gaps in recipient language” and women's motivation is “the social, cultural, political and scientific credibility of donor language”.
- Introduction
The usage of loanwords is not limited to a specific context or field of language. Speakers of each language may use different loanwords in their everyday speech, depending on their individual and social needs or motivations. The current study aims to investigate the usage of loanwords in the spoken Persian from three perspectives: semantics, pragmatics, and sociolinguistics.
Thus, the following research questions are raised:
1. Which semantic fields of loanwords have the highest frequencies in spoken Persian?
2. Are loadwords more related to abstract or concrete concepts?
3. Regarding the gender of speakers, which group mostly uses loanwords with a common Persian equivalent?
4. What are the most important motivations for the use of loanwords by Persian speakers?
- Literature Review
A) Linguistic and sociological studies about loanwords, including Robins (1964), Sapir (1970) and Haspelmath (2009).
B) Corpus-based studies of Persian language, including Sharafi (2000), Mehryar (2003), Sattari (2009), Ketabi et al. (2010), Kargozari & Tafazzoli (2012), Mohammadi & Abdotajedini (2013).
A small number of the mentioned studies have been devoted to the invetigation of spoken Persian and the majority of researchers have studied loanwords in written literature. Moreover, in those limited number of works on spoken Persian, the reaseachers have expolred controlled data, mostly recorded radio and television programs, which are far from normal speech. Thus, as can be seen, this is the first time that the facts of spoken Persian have been studied in terms of the usage of loanwords.
- Methodology
The corpus of this study, being prepared in the Linguistics Department of Al-Zahra University, is the first and currently the only corpus of natural speech for spoken Persian recorded in various social situations. One of the most important features of this corpus is that, unlike other controlled databases, here the researchers have access to natural speech of native speakers. Since the participants are not aware of this fact that their words are being recorded, the results and findings can reveal facts of nature speech and consequently are less biased. There is no need to mention that all privacy concerns have been observed during data collection.
- Results
List 1: loan words of the corpus
| update, upload, application, atom, autobahn (freeway), autobus (bus), add, Adams (chewing gum), address, adrenaline, eau de Cologne (perfume), art brush, agency, SMS, ascenseur (elevator), spray, sport, speaking, spin, strategy, stress, story, astigmat (astigmatism), screen shot, skill, skill worker, slide, off, UK band (brand new), active, expire, express, expression, aklil (glitter), équipe (group), alarm, album, alzheimer's, ampoule, amphitheater, energy, Angry Birds, online, optic, average, urgence (emergency), origin, OK, Oh Yeah!, idea, ideal, immigration, email, intranet, internet, Internet Explorer, entry, battery, bascule (scale), baguette, band, … |
| Atomi (Atomic), energy darmani (energy therapy), ba-class (high-class), Buddayi (Buddhist), post-e- electronic (e-mail), pomp-e-benzon (gas station), testi (by test), telephoni (by telephone), randomi (randomly), size-bandi (sizing), miyan term (midterm), … |
- Conclusion
Men mostly use those loanwords which are often common words in Persian and don’t seem strange, and a small percentage of their loanwords are non-common and have a typical Persian equivalence; However, this percentage is higher for female participants. In other words, in most cases, men’s purpose of using loanwords is to “fill communication gaps in recipient language” and women's motivation is “the social, cultural, political and scientific credibility of donor language”.
Volume 16, Issue 1 (8-2013)
Abstract
Objective: Various approaches have been offered for resolution of pain resulting from spinal cord injuries. One approach is the use of herbal and natural products. In the present research, as a preliminary study, we investigate the effect of crocin on chronic pain induced by contusion in the rat spinal cord (SCI). Methods: We randomly divided female Wistar rats into five groups. Groups I and II were contused at the L1 level and immediately treated with crocin (50 mg/kg). These groups were sacrificed after 2 hours and 1 week, respectively. The remaining three groups consisted of group III (control group), group IV (treated with crocin and no contusion), and group V (the contused group that underwent no treatment). Groups III-V were sacrificed after one week. The mechanical behavioral test that used Von Frey hairs; the thermal behavioral test that used a hot-plate and the locomotor recovery test with Basso, Beattie and Bresnahn (BBB) scoring were conducted daily to evaluate the extent of injury and recovery of the rats. The calcitonin-gene related peptide (CGRP) was determined in the animals' plasma by the ELISA kit. Results: The results showed a significant increase in plasma CGRP of contused rats that significantly reduced following crocin treatment. The behavioral tests were not changed significantly due to this treatment. Conclusion: The present study shows the beneficial effects of crocin treatment that may occur by decreasing CGRP on chronic pain induced by SCI. This project is continuing using higher dose of crocin for longer time.
Volume 17, Issue 5 (9-2015)
Abstract
To introduce ecologically safe acaricide, effects of essential oils derived from Cuminum cyminum (Cumin), Syzygium aromaticum (Clove), and Mentha spicata (Spearmint) were determined on Tetranychus urticae at 25±1◦C, 65±5% RH and a photoperiod of 16:8 (L:D) hour. The essential oils extracted by hydro-distillation were characterized by means of GC and GC–MS. Bioassays were performed by filter paper diffusion without allowing direct contact. Cumin, clove, and spearmint oils contained α- Pinene (29.1%), eugenol (78.5%) and carvone (59.4%), respectively, as the major compounds. The lowest LC50value for adults was recorded for cumin oil (3.74 μL L-1 air) followed by clove (6.13 μL L-1 air) and spearmint (7.53 μL L-1 air). The highest ovicidal activity was recorded for cumin oil (LC50= 7.65 μL L-1 air) followed by clove (LC50= 8.73 μL L-1 air) and spearmint (LC50= 9.01 μL L-1 air). According to repellency tests, by increasing concentration of oils, the repellency effects were increased. The most potent repellency effect was recorded for clove, followed by spearmint and cumin oils. The three extracted essential oils seem to be suitable sources of active vapors that can be used as alternatives for chemical pesticides for controlling this pest.
Mohsen Agha Seyed Mirzabozorg, Saeid Kheradmand, Ali Roueini,
Volume 18, Issue 1 (3-2018)
Volume 18, Issue 1 (3-2018)
Abstract
In this paper, a C-programming code is produced to introduce the best propulsion system including an internal combustion engine combined with turbochargers. Because the power of internal combustion engine will reduce as the altitude increasing, it is required to use one or more turbochargers in order to compensate the loss of power which is caused by reduced ambient air pressure. For this purpose, a code is written that will be able to introduce the best turbochargers combination including intercoolers, according to the target power and the desired altitude of the UAV flight. In other words, input required parameters of the code is the target power of the engine and desired altitude of flight and output of the code is number and characteristics of the turbochargers with their exact manufacturing company names and also the number of intercoolers required for best performance of propulsion system. It should be noted that, if the turbochargers that is chosen by the program are not available, user can select of the similar turbochargers with similar characteristics without any significant difference in performance of the propulsion system.
M. Nazemi Babadi, S. Kheradmand ,
Volume 19, Issue 4 (April 2019)
Volume 19, Issue 4 (April 2019)
Abstract
In this paper, the numerical simulation of the diesel and gasoline fuels injection in a constant volume chamber is conducted under the operating conditions of a compression ignition engine with openFoam software. In order to check out the possibility of using gasoline instead of diesel to increase the volumetric efficiency of the compression ignition engine and reduction air pollution, the spray characteristics of the gasoline and diesel under injection pressures of 40 and 80MPa, as well as temperatures of 243, 273 and 313K, is investigated. The simulation results are compared with the experimental data derived from fast imaging techniques. The results show that under the same conditions, the vapor penetration length for the two fuels is approximately equal. Also, due to the lower volatility of the diesel fuel, its liquid penetration length in 40 and 80MPa injection pressure was found to be 7 and 9 mm higher than gasoline, respectively, and high volatility of gasoline leads to enough time to make air and fuel mixtures in compression ignition engine. In addition, the reduction in fuel temperature from 313K to 243K resulted an increase in the penetration of gasoline and diesel liquids by 12 and 10 mm, respectively, and decrease in the evaporation rate, which causes a non-homogeneous mixture and an increase in unburned hydrocarbons and emissions.
M. Faraji Kheyrabadi, S. Kheradmand,
Volume 19, Issue 6 (June 2019)
Volume 19, Issue 6 (June 2019)
Abstract
In the present work, an investigation and simulation of the air flow, containing solid suspended particles in the actual impactor particles under investigation are in the micron range. The results of this work can be illustrated by simulating the motion of particles in an actual impactor, investigating the effects of temperature changes on the surrounding environment, and the impedance plates on the accumulation efficiency. In the first part, by deriving the governing equations for this phenomenon and choosing the appropriate numerical method for solving these equations, the path of motion is simulated. By determining the path of the particles, it is possible to determine the number of particles deposited on collecting plate, and to the mentioned relations, the collection efficiency is obtained a laboratory experiment, which compared with laboratory values. This comparison indicates the acceptable accuracy of the chosen employed method. In the next section, by selecting particles with different densities, of the environment temperature and inlet air variations by assuming constant plate temperature, and collector plate temperature variation on the impactor efficiency have been investigated. The results show that the particle density affects the efficiency of and reduces the diameter of cut from 2.2 to 4.2 in Due to the increased viscosity of the air, the of reduces the efficiency of The results showed that temperature variation of the collection plate could also change the particle collecting efficiency.
M.m. Nabavi, S. Kheradmand,
Volume 19, Issue 11 (November 2019)
Volume 19, Issue 11 (November 2019)
Abstract
In this research, the heat sink performance of a laser diode with the different geometries was studied. A 3D simulation of flow and heat transfer has been used considering the natural convection. First, in order to test the validity, the simulation results were compared with the experimental results, which were in a good agreement. Then according to the chimney flow pattern, eight geometries were designed with two different heights of the fin and each one of them was evaluated by three heat fluxes of 200, 400 and 600 W/ . The aim of this research is to find the condition that minimizes the average temperature of the heat sink. The results showed that the average heat transfer coefficient in the heat sink is increased up to 40 percent by creating the slice in the fine. In the fins with the height of 21.3 millimeters, the fin with two similar symmetric slices and in the fins with the height of 32.6 millimeters and constant volume that the slices of fine are added to its teeth, for heat fluxes less than 400 W/ , symmetric fin with two similar slices in the middle section and a volume equal to the volume of the primary fin, had the best performance. For heat fluxes, more than 400 W/ , the average temperature of the symmetric fin with one slice in the middle and a volume equal to the volume of the primary fin was minimized. Fin average heat transfer coefficient, average Nusselt number, fin thermal resistance, fin average temperatures, flow streamline and isothermal contour plots in the fin plate were evaluated for each state.
Azam Beigi Kheradmand, Maryam Khalili,
Volume 24, Issue 9 (September 2024)
Volume 24, Issue 9 (September 2024)
Abstract
The aim of this study is to achieve an optimal chemical composition in the metal matrix composite (MMC) (Fe-C-Cu-SiC) to enhance the wear resistance of the composite and evaluate its mechanical properties based on the optimal amount of copper, making it suitable for use in brake pads for aircraft, locomotives, and racing cars. For this purpose, Fe, C, and BaSO₄ with a chemical composition of (6SiC-6.5C-6BaSO₄-Fe) and varying amounts of copper (3%, 7%, 11%, 15%, and 19%) were mechanically milled using powder metallurgy. The materials were then sintered in a furnace with protective gas and hot-pressed at 1000°C and 400 MPa, resulting in five test samples. Wear and friction coefficient tests were conducted under a load of 20 N, at 700 rpm, over a distance of 1000 m. Hardness tests, density measurements, microstructural examination with a scanning electron microscope (SEM), and EDAX analysis were also conducted to assess the wear mechanism. Examination of the worn surfaces indicated that during the initial sliding distance, the predominant mechanism was abrasion. As the sliding distance increased, abrasive and oxidation wear mechanisms, along with plastic deformation, became active. Test results showed that the Fe-15Cu-6.5C-6SiC-6BaSO₄ sample had higher wear resistance and a more suitable friction coefficient (within the acceptable range of 0.2 to 0.4) compared to the other four samples, suggesting its potential application for brake pads.
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