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Showing 13 results for Farshbaf


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

    Entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae are important and effective biocontrol agents against arthropod pests. Compared to chemical insecticides, insect pests do not easily develop resistance against these fungi. In this study, the mortality and phenol-oxidase activity of the Helicoverpa armigera 3rd instar larvae were evaluated after exposure to the B. bassiana and M. anisopliae. The LC50 values for B. bassiana and M. anisopliae were 0.795 ×106, and 5.972 ×107 spore ml-1, respectively. LC30 and LC10 of either entomopathogenic fungi were injected into body of larves, then, 24 and 48 hours after injection, their hemolymph was extracted. After 24 h the highest and lowest phenol-oxidase activity was observed in LC30 of M. anisopliae, and LC10 of B. bassiana, respectively. After 48 h of infection, phenol-oxidase activity increased in all treatments. At the LC30 of M. anisopliae, the highest phenol-oxidase activity was recorded, and other treatments also showed a significant difference compared to the control. Five types of hemocytes including prohemocytes, plasmatocytes, granulocytes, onocytoids, and spherulocytes were identified in the hemolymph of larvae.  The highest total hemocytes count (THC) was recorded in LC30 M. anisopliae at 9 h after initial infection. Our results showed that both fungi have the ability to affect phenol-oxidase enzyme activity. These microbial insecticides exhibited high potential for controlling the pest.



Volume 2, Issue 2 (6-2016)
Abstract

This study was conducted to collect and identify ichneumonid parasitoids of tephritid fruit flies (Diptera: Tephritidae) feeding on the plants of the family Asteraceae in the northwest of Iran during 2013-2015. Five species of ichneumon wasps on five species of fruit flies were reared. They were as follows: Cremastus lineatus on Urophora terebrans; Diadegma maculatum on Hypenidium robrowskii; Scambus brevicornis on Sphenella marginata, Scambus rufator on Terellia gynacochroma and Urophora sp. and Tranosema sp. on Tephritis sp. dioscurea group. Of them, Cremastus lineatus, S. rufator and Tranosema sp. are new records for ichneumonid fauna of Iran. All host-parasitoid-plant associations were newly established to the science. General distribution of these parasitoids and their biological associations were discussed.

Volume 4, Issue 1 (3-2018)
Abstract

Israelius carthami Richards, 1952 was recorded for the first time from Iran, based on reared specimens from three Asteraceae capitulum: Cirsium congestum Fisch. & C.A.Mey., Carthamus lanatus L. and Xeranthemums quarrosum Boiss. In our rearing, a fruit fly species [Terellia nigripalpis Hendel (Diptera: Tephritidae)] was obtained on C. congestum. All host-plant associations are newly established to the science. General distribution of this parasitoid and their biological associations were discussed.

Volume 9, Issue 4 (8-2020)
Abstract

Mediterranean flour moth, Ephestia kuehniella Zeller, is important for mass rearing of parasitoid insects such as Bracon wasps and it's feeding on cereals leads to economic losses in flour mills. In current research, the effects of four different diets: wheat, barley, oat, and maize flours, on protein content of larval and pupal whole-body, gut and fat bodies of the last instars and the digestive α-amylase activity were evaluated. In addition, their protein patterns were compared using polyacrylamide gel electrophoresis (SDS-PAGE). The protein contents of fifth instars whole-body, fat bodies, gut, and also pupa varied in different diets. On the whole, the lowest protein levels were found in all experiments in oat and the highest in barley and wheat. Other biological parameters such as insect weight and digestive α-amylase activity were also significantly affected by the decrease in protein content. The results obtained from the estimation of protein content by a colorimetric method and SDS-PAGE were consistent with each other; the low or high protein contents were also clearly visible in the gels. According to the results of enzyme activity and protein contents of insects reared on different diets, barley and wheat are reported to be appropriate diets for this pest, while oat and maize are not suitable diets.
 

Volume 9, Issue 6 (No. 6 (Tome 48), (Articles in Persian) 2018)
Abstract

         In systemic functional typology, which studies the systems of languages rather than the whole languages, linguists strive towards empirical generalizations that in principle apply to all languages around the world. In line with the above-mentioned goal of systemic functional typology and having examined the ideational (logical and experiential), interpersonal, and textual systems of the ‘clause grammar’ of different and various languages, Matthiessen (2004) has achieved a series of typological generalizations/universals. In connection with his proposed typological generalizations, Matthiessen (2004) has argued that they can be applied in the description of any language and in the attempt to expand the typological explanations in the framework of systemic functional grammar as well. However, he has immediately stated that “It is not yet possible to propose a generalized map; but we have to move in that direction.”
         In line with Matthiessen’s claim mentioned above, the present paper has attempted to describe the THEME system of Azeri Turkish on the one hand and compare it with the THEME system of Persian language on the other hand. This research has been conducted in terms of the following three typological parameters concerning the THEME system: (1) The treatment of unmarked and marked THEME (related to the subsystem of THEME MARKEDNESS), (2) The relationship between THEME and MOOD (related to the subsystem of THEME SELECTION), and (3) The relationship between experiential (topical) THEME and interpersonal and textual THEME (related to the subsystems of THEME TYPE, INTERPERSONAL THEME, and TEXTUAL THEME).
         Studying typological behaviors of the Azeri Turkish THEME system in the framework of Matthiessen (2004)’s typological generalizations and comparing those behaviors with the typological behaviors of the Persian THEME system show that the two languages of Persian and Azeri Turkish (1) have an almost identical thematic structure, (2) treat both unmarked and marked Themes similarly, (3) have multiple types of Themes beside simple ones, (4) treat the elements of a multiple Theme similarly, and (5) have a MOOD-free THEME system. These findings show that both languages, which are genealogically different, have a similar THEME system and specifically the three subsystems of THEME MRKEDNESS, THEME SELECTION, and THEME TYPE. This result is consistent with ‘axial principle of congruence’. According to this principle, languages tend to be more congruent with one another in terms of paradigmatic axis/system than in terms of syntagmatic axis/structure.
         In the end, it is suggested that the typological behaviors of the THEME system of other languages spoken in Iran be identified and introduced in the aforementioned framework.
 

Volume 11, Issue 1 (1-2022)
Abstract

The Sunn pest, Eurygaster integriceps (Puton) (Hem.: Scutelleridae), is an economic pest of wheat that reduces the quantitative and qualitative properties of wheat products. We investigated the effect of E. integriceps feeding on six different wheat cultivars (Ghermez (Red), Noodle, Antanius, Sabalan, Azar 2 (with two types of cultivation), and Sardari) on the protein content in the adult’s gut and fat body and their digestive enzymatic activity. All qualified values of the insect feeding on wheat cultivars differed significantly. The least amount of adult weight and protein content of gut and fat body were observed in the insects fed on Ghermez (Red) cultivar, and the highest amount belonged to the Sardari cultivar. The same results for protein content were obtained from SDS-polyacrylamide gel electrophoresis (SDS-PAGE). Also, the lowest and highest gut α-amylase, pectinase, and protease activities were in Ghermez and Sardari cultivars, respectively. Therefore, it was concluded that the type of wheat cultivar affects the food preference of this insect and, thereby, physiological parameters of the insect gastrointestinal tract. Planting a wheat cultivar like “Ghermez,” which may be resistant, can be a suitable and cost-effective method to decrease the chemicals applied against this pest.

Volume 12, Issue 2 (9-2023)
Abstract

The cotton bollworm, Helicoverpa armigera (Hübner), is one of the most important pests of crops. Like other insects, this insect has an immune system against external threats such as various diseases, parasitoids, and chemical compounds. Phenoloxidase is a key factor in the immunity of insects and other arthropods. The present study investigated the lethal effects of four insecticides, indoxacarb, profenofos, chlorfluazuron, and hexaflumuron, and their effects on phenolic oxidase activity in cotton bollworm. Among the studied insecticides, in two bioassays (mixture of insecticide with artificial food and immersion of sugar beet leaves), Chlorfluazuron had the highest toxicity (LC50 = 1.71 and 3.11 mg ai/liter, respectively). Also, the highest phenol-oxidase activity at 24 h was for larvae treated with chlorfluazuron and hexaflumuron. Also, when treated with chlorfluazuron and hexaflumuron, the larvae fed on an artificial diet had higher phenoloxidase activity than those fed on sugar beet cultivars.

Reza Farshbaf Zinati,
Volume 15, Issue 5 (7-2015)
Abstract

In the current work, a modified method of friction stir process (FSP) based on ultrasonic vibration and modified FSP tool design was developed to disperse multi-walled carbon nano-tube (MWCNT) throughout nylon 6 matrix. To this end, Field emission scanning electron microscopy, X-ray diffraction, Vickers’ micro-hardness, and visual inspection were used to evaluate the fabricated nano-composites. Also, a modified design of FSP tool together with ultrasonic vibration were used to improve the impact and efficiency of FSP. Several experiments were conducted to approach an optimum range of FSP parameters (rotational speed and traverse speed). The scanning electron microscopy observations and X-ray diffraction patterns (XRD) declare that MWCNT was dispersed homogeneously throughout nylon 6 matrix. Micro-hardness results illustrate that homogeneous dispersion of MWCNT throughout nylon 6 matrix results in 33% increase of micro-hardness. In general, the obtained results declare that ultrasonic vibration causes an increase in traverse speed and production speed of nano-composite without affecting the homogeneous dispersion and hardness of nano-particles throughout the matrix. Also, it is clear that ultrasonic vibrations did not noticeably affect superficial form of nano-composites due to low traverse speeds used in ultrasonic assisted friction stir process.

Volume 16, Issue 5 (9-2014)
Abstract

Trissolcus grandis (Thomson) (Hymenoptera: Scelionidae) is the most important egg parasitoid of the common sunn pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae) in Iran. Demographic characteristics may be used for preliminary screening of parasitoid species or populations as well as for predicting their efficiency under different physical conditions in the field. In this study, the demography of two northwestern populations of T. grandis was studied under five constant temperatures including 20, 23, 26, 29, and 32±1°C, at 50±5% RH and 16:8 h (L: D) photoperiod. The two populations responded differently to the temperatures, thus, many life history parameters were significantly affected not only by temperature itself but also in interaction with population. The highest value of intrinsic rate of increase for the Marand population was 0.344±0.057 females/female/day that occurred at 26°C. The same rate for the Tabriz population increased regularly with temperature increase and the maximum value (0.368±0.063) was obtained at 29°C. Further increase in temperature led to a negligible change in the value of this parameter. As a whole, the Marand population seemed to be adapted to cooler conditions compared to the Tabriz population
Mohammad-Reza Sayyed Noorani, Maryam Shoaran, Sahar Farshbaf,
Volume 16, Issue 12 (2-2017)
Abstract

Locomotion regulation of a robot according to path conditions is one of the main interests in the robotics, because it enables the robot to move in unknown environments. This can be realized using inspiration from the human and animals' bio-mechanism in generating various motion patterns called central pattern generator (CPG). These motion patterns are called “gaits” and changing between the motion patterns is called “gait transition”. Many models have been proposed to model CPGs and used for trajectory generating of various mobile robots. In this paper, a type of CPG network called 4-cell CPG model is studied to generate the rhythmic signals of the ankle joints in a bipedal locomotion gaits. This model is composed of four coupled identical cells whose internal dynamics is described by the Morris-Lecar nonlinear differential equations and the couplings between the cells follow the diffusive type. The generation of various locomotion gaits depends on the adjustment of the phase differences between rhythmic signals produced by the cells. The phase differences, in-turn, are obtained via properly adjusting the coupling weights between the cells. Here, we exploit a non-dominated sorting genetic algorithm (NSGA-II) to find the best set of coupling weights for maximally approaching the desired phase differences of the primary bipedal gaits of walk, run, two-legged jump, and two-legged hop. Also, some secondary bipedal gaits, especially one that called “hesitation walkˮ, are obtained by symmetry breaking bifurcations of the primary gaits. The “hesitation walkˮ has already predicted in [28], however the authers could not generate it.

Volume 18, Issue 7 (Supplementary Issue - 2016)
Abstract

Potato tuberworm, Phthorimaea operculella Zeller (Lepidoptera; Gelechiidae) is a worldwide pest of solanaceous crops. Larvae feed inside galleries in foliage, stems and tubers making chemical control unsuccessful, so other control methods should be applied. In recent years many plants have received genes that encode toxic proteins as a strategy to resist insect pests. In this study, optimal pH and temperature of digestive α-amylase and protease activities of potato tuberworm and the effect of triticale (X Triticosecale wittmack cv. Sanabad), rye (Secale cereale L. cv. Danko) and black nightshade (Solanum nigrum L.) seed proteinaceous extracts against enzymes activities were evaluated using starch 1% and azocasein 2% as a substrate, respectively. The optimum pH of α-amylase and protease activities was found to be highly alkaline. Enzymes inhibition assays showed that amylase activity was significantly affected by extracts from triticale and rye by pH (P= 0.05; maximum effect at pH 9) and influencing of protease activity by extracts mentioned above did not vary by pHs 8-11 and 9-11, respectively. Extracts from black nightshade seed had no effect on enzymes activity. Inhibition manner of various concentrations; 1.5, 0.75, 0.375, 0.187 and 0.093 (mg protein ml-1) of extracts were dose-dependent. Maximum inhibitory effect occurred at the highest concentration and the minimum was at the lowest concentration. In polyacrylamide gel assay, both enzymes, without inhibitors showed two isozymes, which at highest concentration of extracts, both bands disappeared or their intensity decreased. So, these proteins can be introduced to be encoded in producing resistant potato crops against potato tuberworm.

Volume 19, Issue 3 (5-2017)
Abstract

The aim of the present work was to purify cysteine protease inhibitors from rapeseed (Brassica napus L.), with potential activity on digestive protease of Colorado Potato Beetle (CPB), Leptinotarsa decemlineata (Say). Ammonium sulfate precipitated proteinaceous fractions; 30, 50, 70, and 100% showed 39.07, 57.03, 51.47, and 22.44% inhibition on the fourth instar larval gut general protease activity, respectively. Fraction 50% showed the highest inhibitory effect on digestive general protease activity of all developmental stages. Gel assays approved the inhibition of the enzyme activity. Fraction 50% was purified by using various chromatography techniques; ion-exchange using DEAE, gel filtration and affinity using SiO2-CPB larval gut homogenate. Three peaks of protein were eluted from ion exchange chromatography using NaCl step gradient, also from gel filtration chromatography. When Z-Ala-Arg-Arg-4mßNA was used as cysteine protease substrate, the purification fold of second fraction of ion exchange chromatography was obtained 24.80, also the yield was 59.09%, the third fraction of gel permeation resulted in a 25.60 fold purification with 28.53% of recovery, and the fraction of affinity chromatography obtained a 22.72 fold purification and yielded 36.35%. In the SDS-PAGE, apparent molecular mass of purified proteins were 34 and 32 kDa by ion-exchange and 24 and 22 kDa by affinity. However, gel filtration was not an appropriate method in this study, because the purified protein band(s) were not observed on the gel. Consequently, these chromatography methods were appropriate methods to purification of inhibitor cystatins, specially affinity which was prepared by using CPB gut enzyme as ligand and obtained specific inhibitor proteins of CPB gut protease activity.
M. Farshbaf, M.a. Mofid, M. Belbasi, M. Jafarzadegan, H. Naeimian,
Volume 20, Issue 10 (October 2020)
Abstract

Thermal spraying is economical and rapid coating process that creates a rough and clean surface. As a result it can be used for applying the interlayer in transient liquid phase bonding. In the present study, transient liquid phase bonding Al 2024 to Ti-6Al-4V was investigated using brass interlayer, where the interlayer was Cu-Zn foil Cu-Zn thermal spray coat on Al substrate, respectively. The results show that by using thermal spray coat as interlayer, because of the formation of different defects that can be considered as diffusion channels, diffusion potential of Ti and Al becomes higher at the interface. It is concluded that the mechanism of bonding formation involves the diffusion of Cu into Al and Ti base materials and formation of TiAl، TiAl، Cu2 Al and AlCuMg phases and also diffusion of Cu through Al grain boundaries and formation of eutectic phases across the grain boundaries. The formation of these intermetallic phases was confirmed by energy dispersive spectroscopy and X-ray diffraction. Dissolution of the base metals in the joint area and the isothermal solidification process of the thermal sprayed interlayer is more and faster than the foil interlayer. The joint with thermal spray brass coat as interlayer, gives higher shear strength of 25 MPa in comparison with the case of using brass foil as interlayer (14.6 MPa). The decrease in bond strength can be attributed to aggregation and growth of the brittle intermetallics near the joint interface due to lower diffusion potential of Ti and Al in the joint zone.

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