482 research outputs found
Szalicilsav által szabályozott védekező mechanizmusok vizsgálata gabonafélékben = Investigation of protective mechanisms controlled by salicylic acid in cereals
A pályázat cĂ©lja az volt, hogy megvizsgáljuk az exogĂ©n szalicilsav (SA) hatását kĂĽlönbözĹ‘ abiotikus stresszek során, valamint hogy megvizsgáljuk hogyan alakul az endogĂ©n SA szint stresszkörĂĽlmĂ©nyek között gabonafĂ©lĂ©kben. Hidegstressz során nem volt kĂĽlönbsĂ©g a kontroll Ă©s a SA kezelt növĂ©nyek membránlipidjeinek zsĂrsavösszetĂ©telĂ©ben, mĂg a SA elĹ‘kezelĂ©s megemelte a putreszcin Ă©s a spermidin szintjĂ©t, Ă©s ez is hozzájárul valĂłszĂnűleg a SA vĂ©dĹ‘hatásához. Szárazság stressz ellen a SA nemcsak, hogy nem nyĂşjtott vĂ©delmet, hanem fokozta annak károsĂtĂł hatását. NehĂ©zfĂ©mstressznĂ©l (Cd) a SA kezelĂ©s hatására gyökĂ©rben jobban csökkent a fitokelatin szintáz enzim aktivitása, mĂg levĂ©lben megnĹ‘tt. Szárazság stressz során kukorica (Norma hibrid) mind a kötött, mind a szabad endogĂ©n SA szint lecsökkent gyökĂ©rben, mĂg levĂ©lben drasztikus stressz hatására megnĹ‘tt. NaCl kezelĂ©snĂ©l a levĂ©lben a szabad SA szint kismĂ©rtĂ©kben megnĹ‘tt, gyökĂ©rben nem változott, a kötött mind levĂ©lben, mind gyökĂ©rben lecsökkent. Cd stressz során gyökĂ©rben mind a szabad mind a kötött SA tartalom megnĹ‘tt. Az abszcizinsav kezelĂ©s normál hĹ‘mĂ©rsĂ©kleten nem befolyásolta az SA szintet, mĂg egy nap 5°C-os alacsony hĹ‘mĂ©rsĂ©kleti stressz során a szabad SA szint megnĹ‘tt, a kötött pedig lecsökkent, mind levĂ©lben, mind gyökĂ©rben. Ezek alapján megállapĂthatjuk, hogy a szalicilsav szerepet játszik abiotikus stresszek során. | The aim of the project was to examine the effect of exogenous salicylic acid (SA) during various types of abiotic stress, and to determine how the endogenous SA level changed under stress conditions in cereals. During cold stress no difference was observed in the fatty acid composition of membrane lipids between control and SA-treated plants, while preliminary treatment with SA caused a rise in the levels of putrescine and spermidine, probably contributing to the protective effect of SA. Rather than providing protection against drought stress, SA made the damage more severe. In the case of heavy metal (Cd) pollution the phytochelatin synthase enzyme activity was further reduced by SA in the roots, but increased in the leaves. During drought stress there was a reduction in the level of both bound and free endogenous SA in the roots of maize (hybrid Norma), while it increased in response to drastic stress in the leaves. Treatment with NaCl caused a slight increase in the free SA level in the leaves, while no change was observed in the roots; the bound SA level declined in both leaves and roots. During Cd stress there was an increase in both free and bound SA content in the roots. At normal temperature abscisic acid treatment had no effect on the SA level, but after one day of low temperature stress (5°C) there was an increase in free SA and a drop in bound SA in both leaves and roots. It is thus clear that salicylic acid plays a role in the response to abiotic stress factors
DESIGN TASKS SCHEDULING USING GENETIC ALGORITHMS
This paper deals with a modelling and optimization method that is capable of
the product structure based optimization of design processes. The processes
were modelled with Design Structure Matrix. Guided stochastic search
techniques were applied when finding the optimal task schedule. The impact
of the probability of mutation and crossover and the two different selection
processes on searching was examined. Further investigations were completed
in order to multi-object optimize the time and cost of design processes
Laboratory and numerical investigation of direct shear box test
In agriculture, food, chemical, plastic and pharmaceutical industries for designing and operating machines, it is essential to determine the mechanical parameters of the processed granular materials. In most cases, these characteristics are the internal friction angle, the contact cohesion developed by the surface moisture and the apparent cohesion occurred by the shape of the granular material. Further physical quantities are required to characterize the motion state of the particles, which were determined by laboratory measurements in this study. Hulled mil- let was used for the measurements because its geometric shape can be modeled as sphere in the numerical investigations with good approximation. The porosity, the particle and bulk den- sity of the hulled
millet were determined by means of an air pycnometer in case of several moisture content. Using laboratory direct shear box test, under standard conditions, the shear strength of the cohesive liquid bridges and the internal friction angle in the bulk were deter- mined. The results obtained were used for input parameters of a discrete element model. The aim of this research was to determine the micromechanical parameters by simulation, based on the macromechanical results of the hulled millet bulk during laboratory measurements
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