Showing 4 results for Enferadi
Volume 13, Issue 6 (Number 6 - 2011)
Abstract
The response of five inbred sunflower seedling lines, including AC 4122, C, HA 89, HA 410, HA 411, to inoculation with Sclerotinia sclerotiorum culture filtrate containing endogenous oxalic acid was compared with the exogenous application of synthetic oxalic acid. The reaction of seedlings was evaluated in terms of dry and fresh plant weights and the total chlorophyll concentration relative to untreated controls. The expression of shikimate dehydrogenase in cotyledons was also assessed five days after treatment. The results indicated that exogenous oxalic acid inoculation caused more deleterious effects on stem rot, eliciting photosynthesis reduction and different isoenzyme patterns of shikimate dehydrogenase. A positive correlation was found between increased oxalic acid and shikimate dehydrogenase activity in both treatments. However, the excessive toxicity of the exogenously administrated acid suggests that Sclerotinia sclerotiorum infection triggers a more complex metabolic pathway involving oxalic acid secreted by the pathogen. These observations preclude the possibility of using the synthetic acid administration as a method of screening sunflower genotypes for resistance to Sclerotinia. In addition to these findings, the reactivation of shikimate dehydrogenase was observed in both treatments. In contrast to synthetic administration, expression during the first phase of growth may serve as a tool for rapid screening and selection of sunflower genotypes resistant to Sclerotinia sclerotiorum.
Volume 17, Issue 6 (11-2015)
Abstract
Keeping constant all agronomic factors except temperature is a way to follow Heat Shock Proteins (HSPs) expression. Three different sunflower hybrids derived from the cross between an inbred line, Cms HA 89, and three different restorer inbred lines, with resistance, susceptible, and normal reactions to drought, were produced. In order to investigate the impact of temperature on protein accumulation during achene filling phase, they were cultivated in two different geographical areas: Karaj in Iran and Udine in Italy. Total protein content and structural polypeptide fractions of Seed Storage Proteins (SSPs) were determined. The analysis of HSPs was carried out by means of lab-on-chip capillary electrophoresis. It was revealed that protein accumulation in achene occurs at a greater rate during the achene filling phase, i.e. approximately 9-25 days after pollination, in all examined hybrids. Besides, the presence of a polypeptide band of 17.7 kDa supposed to be of small Heat Shock Proteins (sHSPs) family was recorded in all three hybrids grown up in hot and arid environment, Karaj, which implied independent sHSPs expression from the paternal restorer line.
Nader Nabavi, Alireza Akbarzadeh Tootoonchi, Javad Enferadi,
Volume 17, Issue 6 (8-2017)
Abstract
Todays, parallel robots with six degrees of freedom are widely used in motion simulation industry. Spreading application of motion simulation for different means of transportation has led to advance training in a safe way with less time and equipment cost. Mostly, the 6-UPS structure Stewart parallel manipulator is used as motion simulators due to their large workspace, rigidity and load capacity. Since the massive moving actuated prismatic joint is located between fixed and moving platforms, the dynamic performance of the mechanism is not efficient. The robot with PUS structure can be a good alternative for UPS type as its actuators are fixed to the ground. This results in lowering of the overall robot cost in addition to stiffness increase. In this paper the inverse kinematic and dynamic of a general 6-PUS robot is presented using Newton-Euler method. The theoretical dynamic model results are verified using motion analysis software. A simplified dynamic model is prepared eliminating links’ inertial terms from dynamic equation. The accuracy of the model is evaluated for different link to payload mass properties ratio. The simplified dynamic model used to improve the computational efficiency of the inverse dynamics.
M.h. Enferadi, M.r. Ghasemi, N. Shabakhty,
Volume 20, Issue 1 (January 2020)
Abstract
Service life and safety of a steel jacket platform is influenced by vibrations generated by environmental loads, waves and winds. Vibrations of the structure and deck may cause fatigue in the structural elements and joints. Also may disrupt the operation of the drilling equipment and facilities as well as the operation of the platform. Therefore, the main aim of this research is to control the vibrations of the steel jacket platform through shape memory alloys dampers. Shape memory alloys have two important properties of shape memory as well as superelastic behavior and are quite suitable for damping applications. In these alloys, crystal structures transition from the austenite to the martensite phase, and vice versa are accompanied by the energy dissipation. In this research, a 90m steel jacket structure equipped with SMA dampers installed in 80m water depth has been modeled as a multi-degree-of-freedom system and analyzed under the time history of wave loads. For solving the differential equations of system vibration and modeling the hysteresis behavior of the shape memory alloys elements, the direct integration alpha method and multi-linear idealized constitutive model have been used, respectively. Jacket platform equipped with the shape memory alloys dampers shows the better result with 42% reduction in deck displacement, 62% reduction in deck acceleration and 32% reduction in shear force of platform base.
