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Showing 4 results for کهریزی
Volume 10, Issue 2 (Spring 2019)
Abstract
Maize (Zea mays L.) is one of the most cultivated crops worldwide, owing to its versatility and wide adaptability, and serves as food, animal feed, and raw material for various industrial products. The purpose of the current research was the classification of maize inbred lines in order to produce hybrid seeds based on agro-morphological traits. Each of 100 maize inbred lines was planted in 6 pots as 6 replications and arranged in completely randomized design in an open area near to greenhouse in 2015. The result of the analysis of variance revealed significant differences among lines for all studied traits. The highest correlation was seen between cob’s length and cob’s weight. Stepwise regression analysis revealed that 66.4% of seed yield per plant variation was determined by cob’s length and cob’s weight. Cluster analysis divided inbred lines into 4 groups. The highest Mahalanobis distance (28.07) was observed between cluster 2 and 4. The result of principal component analysis confirmed the calcification by cluster analysis. The genotypes from groups 2 and 4 can be potentially used as parental lines in hybrid varieties production and development of segregating populations.
Volume 11, Issue 1 (4-2011)
Abstract
Abstract:
The influence of cement content increase on corrosion resistant behavior in concretes
containing nano-SiO2 was experimentally studied. For comparison, the chloride diffusion of
plain concrete and the concrete containing nano-SiO2 was also experimentally studied. The
test results indicated that the corrosion resistance of concretes containing nano-particles is
significantly improved. However, the index of diffusion chloride ion in the concretes
containing nano-SiO2 is directly related to cement content in the mix. The SEM oservations
revealed that the microstructure of concrete with nano-SiO2 is more uniform and compact
than that of normal concrete, but higher pore size distribution was observed when cement
content is increased, which in turn leads to the increase in the diffusion of choloride ion.
Volume 13, Issue 2 (4-2010)
Abstract
Objective: The theraputic exercise is regarded as one of the most important theraputic interventions in the chronic low back pain patients. Stabilization exercise is among the most significant practical ones in these patients. The study of the effects of these exercises on the variability of trunk muscles postural strategies and the ability in normalizing these strategies are among the uncertainties that have remained unknown up to the present time. The purpose of this research is the study of the effect of stabilization exercises on the variability of postural control strategies in these patients.
Materials and Methods: The study was performed on 21 (14 males, 7 females) recurrent non-specific low back pain patients. The electromyographic activity of Deltoid, Transverse Abdominis/Internal Oblique, External Oblique and Erector Spinae muscles of each person was recorded in 75 rapid arm flexion with maximum acceleration. Then, 14 individuals were placed in the experimental group and 7 in the control group randomly.The experimental group performed isolated abdominal hollowing and bracing exercises using pressure biofeedback with the supervision of a physiotherapist in different positions including supine, sitting on a chair, standing still and standing with rapid arm raises with maximum acceleration once a day, for 20 sessions. The variables studied in this research were evaluated in both experimental and control groups after the training sessions. The standard deviation of the trunk muscles onset latencies relative to deltoid muscle was statistically analyzed by a dependent t-test in both groups.
Results: The results revealed that performing the stabilization exercises increases the variability of the timing of anticipatory postural adjustments in TrA/IO in the experimental group (P=.037), while there were no significant changes in the variability of EO (P=.0346) and ES (P=.673) muscles in these patients. The variability of the timing of the anticipatory postural adjustment in TrA/IO (P=.199), EO (P=.702) and ES (P=.465) muscles did not show any significant changes in the control group.
Conclusion: The study of the results showed that the reduction in the variability of postural control system in recurrent non-specific low back pain patients as a factor that causes the continuity of back pain can be improved by goal-directed stabilization exercises.
Volume 15, Issue 77 (9-2018)
Abstract
