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Mayetiola destructor (Say, 1817) originated in the Fertile Crescent region of the Middle East and is one of the most serious pests of wheat, rye and barley and more than 16 Poaceae wild species. Here, we report the occurrence of this species as an invasive pest for the first time in Iran. It was detected in wheat fields and rye in Qüshchï Pass, Urmia environ, West Azarbaijan province (September 2020) as well as in wheat fields in Bil-e Savar, Ardabil province (July 2024). The diagnostic characters and its life history as well as the photographs of the adult male and female, larvae, puparium, male genitalia and wing venation are provided. This is the second species from the genus Mayetiola that has been reported from Iran. To prevent the spread of this destructive pest in Iran, suitable management practices are urgently needed.

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Drought is a complex natural phenomenon that can occur in any climate. Hydrologic drought in the river flow of arid and semi-arid areas causes serious shortages, threatens the quality of life, and impacts on the economy. Understanding this feature is then essential for the management of water resources. Hydrologic drought in the sense of deficient river flow is defined as the periods that river flow does not meet the needs of planned programs for system management. In the present study, changes in the monthly discharge of 14 hydrometric stations throughout the Gorganroud watershed over 30-year period (1980-2010) were studied. Then the deficit flow was determined based on threshold level method, and the results were analyzed. It was revealed that periods of severe shortages have happened in the very humid and semi-arid climates and the downstream of the study area, while longer periods (28 months) of low flows have occurred in the arid climate. The trend of severity and persistence in the central stations of the watershed was increasing. Also shortages occurred with greater frequency at the end of the study period, and river flow shortage during the years 1998-99, 2007-2008, 2008-2009 and 2009-2010 has occurred in most of the stations. So in these years, flow deficit has happened in 50, 85.9, 64.3 and 92.8 %of the stations, respectively.

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International trade expansion and export development have been the center of attention by the economists, policy makers and the cornerstone of planning in many countries of the world. Agricultural and industrial sectors are the crucial economic sectors in every country that have a parity role in preparing food for people and industrial inputs. This article using vector error correction models considers the simultaneous effect of economic policies on agricultural and industrial exports during the years 1971 to 2005. After testing the stationery, Johansen test was used for long run estimation. Results have shown that monetary policy has positive and significant effect on industrial and agricultural exports in short run, while interest rate and government expenditures have significant inverse and direct effect on industrial and agricultural exports respectively, and exchange rate policy has the same effect on industrial and agricultural export in long-run. Finally, the strength of each variable was investigated on export. It is recommended that increasing non oil export, the real value of interest rate is determined and by rising volume of money and then investing it and improving commodity supply, inflation will decrease and therefore non oil export will increase.

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In this paper, with the assumption of constant material properties, the nonlinear behavior of beams is studied using the finite element method. To this end, two approaches are represented: in the first approach, the beam is modeled by one dimensional elements of second order that is formulated according to continuum mechanics relationships based on the Lagrangian strategy, while in the second approach based on the Eulerian strategy the nonlinear behavior of the beam is investigated by making use of two dimensional elements. In both approaches, the second configuration, strains and stresses in the beam are obtained via the calculation of deformation gradient

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The present study was conducted to estimate correlations among performance and egg quality traits in Iranian native fowl. Data were collected from 21,679 birdsat the Isfahan Native Fowl Breeding Center to derive genetic parameters for performance traits and egg quality traits were measured on eggs of 1,020 birds. Genetic correlations of performance and egg quality traits were estimated with a bivariate animal model using ASREML software. Body weight at hatch, 8, and 12 weeks of age (BW₀, BW₈ and BW₁₂, respectively) positively (0.05 to 0.82) correlated with egg weight (EW), shell weight (SW), specific gravity (SG), yolk height (YH) and albumen weight (AW). BW₀ and BW₁₂ negatively (-0.10 to -0.26) correlated with shell strength (SS) and shell thickness (ST). Genetic correlations of BW₈ and BW₁₂ with albumen height (AH) and Haugh unit (HU) were highly negative (-0.45 to -0.55), whereas BW₁₂ showed positive correlation with shape index (SI) (0.22). Shell weight showed high positive genetic correlation with age at sexual maturity (ASM) (0.75), while its genetic correlation with egg number (EN) was highly negative (-0.71). EN also showed high negative correlation with yolk and albumen weight (-0.91 and -0.75, respectively). Based on the present results, selection for higher BW will lead to production of eggs with higher internal quality. In contrast, this kind of selection will reduce the shell strength and shell thickness. Therefore, selection should be based on an index including performance and egg quality traits. This will help to develop indigenous strain of meat-cum-egg type chicken.

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In this paper, cracking in the first mode (opening) is modelled for reinforced concrete beams with FRP sheets based on presenting a new method by using the principles and relations of fracture mechanics and finite element method. In this method, for modelling the relationships of determining the stress intensity factor is developed for reinforcement sheet. In the proposed method, elements of the beam are divided into two categories, including elements with and without the crack. In the elements without the crack, the relationships, equation, stiffness and mass matrices of the beam are established with considering the changes in the moment of inertia due to the reinforced FRP sheet. In the elements with the crack, a change in the cross-section of the reinforced concrete due to the crack and a discontinuity in the crack point leads to an improvement in the standard governing relationships. So that the reduction of the stiffness of the cracked element is equivalent to the change in the size of the discontinuity. Here, the variation of the stiffness of the cracked element is calculated and presented as a function of the stress intensity factor. In this approach, the simulation of the crack is done by dividing the element to two sub-elements into the two sides of the rotational spring. In which, The stiffness and mass matrices of the two sub-elements and the improved stiffness and mass matrix of the element are derived by satisfying the continuity equation at the crack point. This method is developed from a vibrating analysis. The effects of crack depth and location and the effect of crack expansion on the static and vibrational behaviour of a concrete beam are investigated. To ensure the accuracy of the proposed method, all analysis performed in Abacus software is implemented. Comparing the results of the proposed model with the results of comprehensive modelling in Abacus software is applied to verify. The comparison of the results shows that the proposed methods are suitable for the analysis of reinforced concrete structures resistant to cracking. So that it can be generalised and optimally desirable for other models. In this paper, cracking in the first mode (opening) is modelled for reinforced concrete beams with FRP sheets based on presenting a new method by using the principles and relations of fracture mechanics and finite element method. In this method, for modelling the relationships of determining the stress intensity factor is developed for reinforcement sheet. In the proposed method, elements of the beam are divided into two categories, including elements with and without the crack. In the elements without the crack, the relationships, equation, stiffness and mass matrices of the beam are established with considering the changes in the moment of inertia due to the reinforced FRP sheet. In the elements with the crack, a change in the cross-section of the reinforced concrete due to the crack and a discontinuity in the crack point leads to an improvement in the standard governing relationships. So that the reduction of the stiffness of the cracked element is equivalent to the change in the size of the discontinuity. Here, the variation of the stiffness of the cracked element is calculated and presented as a function of the stress intensity factor. In this approach, the simulation of the crack is done by dividing the element to two sub-elements into the two sides of the rotational spring.

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