26 research outputs found

    An Integrated Design and Simulation Environment for Rapid Prototyping of Laminate Robotic Mechanisms

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    Laminate mechanisms are a reliable concept in producing lowcost robots for educational and commercial purposes. These mechanisms are produced using low-cost manufacturing techniques which have improved significantly during recent years and are more accessible to novices and hobbyists. However, iterating through the design space to come up with the best design for a robot is still a time consuming and rather expensive task and therefore, there is still a need for model-based analysis before manufacturing. Until now, there has been no integrated design and analysis software for laminate robots. This paper addresses some of the issues surrounding laminate analysis by introducing a companion to an existing laminate design tool that automates the generation of dynamic equations and produces simulation results via rendered plots and videos. We have validated the accuracy of the software by comparing the position, velocity and acceleration of the simulated mechanisms with the measurements taken from physical laminate prototypes using a motion capture system

    Detection QTLs for Grain Quality Traits and Yield in Two BILs Population of Rice

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    . Rice, the second most important crop after wheat, has been cultivated in Iran. Marketing conditions and quality traits after yield are the most important factors to adopt of new varieties. Therefore in recent years Iranian scientists decided to training on breeding improved high yield varieties with good grain quality.Quantitative trait loci (QTLs) yield and grain quality traits of rice (Oryza sativa L.) with additive, epistatic, and QTL × environment (QE) interaction effects were studied using a mixed-model-based composite interval mapping (MCIM) method and two populations of Back cross inbred lines (BILs) with a common maternal parent.In each of the populations two or three main effects of QTLs were detected for yield, amylose content, gel consistency and gelatinization temperature. Some identified QTL clusters suggested pleiotropic effects could control these traits. The phenotypic variation of AAE and AA QTLs effects were smaller than main QTLs. We conclude that the major genes and some minor and modifier genes controlled rice grain quality and yield components. The information obtained in this study have used to manipulating the QTLs for these traits by molecular marker-assisted selection and the best lines with excellent quality and high yield recognize

    Guidelines and Safety Practices for Improving Patient Safety

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    AbstractThis chapter explains why clinical practice guidelines are needed to improve patient safety and how further research into safety practices can successfully influence the guideline development process. There is a description of the structured process by which guidelines that aim to increase the likelihood of a higher score are created. Proposals are made relating to (a) the live updating of individual guideline recommendations and (b) tackling challenges related to the improvement of guidelines

    Stability Analysis in Oat Cultivars Using Additive Main Effects and Multiplicative Interaction Effects (AMMI)

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    Assessment of the stability and adaptability of a genotype to different environments is useful for recommending cultivars for known conditions and is one of the requirements in plant breeding programs. Considering the inherent climatic diversity in Iran, recognition of genotype by environment interaction is important. In this study ten oat (Avena sativa L.) genotypes were tested at six environments in Shahrekord University for two years and 3 replications in a randomized complete block design (RCBD). AMMI analysis (additive main effects and multiplicative interaction effects) was used to evaluate yield stability of oat genotypes. Results of simple and combined ANOVA for grain yield, showed significant differences for genotype and genotype × environment. AMMI analysis also revealed significant difference for treatment, genotype, environment and genotype × environment. Based on the bi-plot of the first principal component and mean in AMMI method, Rigodon, Paisley and Sioux genotypes showed the most stability and Sioux genotype indicated the smallest IPC1, while Pacer was considered to be the most, unstable genotype

    Investigate the Effect of Stagnant Zone Behavior in One-Dimensional Hydrodynamic Models and Solute Transport in Rivers

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    Introduction Showing the rivers as a one-dimensional problem has simplified or eliminated many processes affecting salinity transfer in the river. Storage processes are one of the factors affecting water quality in rivers. Generally, as a substantial factor, the limitation of observational data confines the use of two-dimensional and three-dimensional models, leading to the use of more widely employed one-dimensional models. Most existing computer models are developed based on the Advection-Dispersion Equation (ADE) and do not consider the storage zone. For this purpose, Modified Advection-Dispersion Equation (MADE) is proposed to consider the stagnant area by defining effective velocity and dispersion coefficient. In this study, a solution has been proposed to apply the effect of the Stagnant zone in water quality simulation in one-dimensional models. The river simulation is closer to the natural conditions. In this model, to prove the improvement of the proposed method, the average stagnant zone fraction expressed as the fraction of the average cross-sectional area of the river (η) and employed in a one-dimensional model through the definition of the effective velocity and the dispersion coefficient. This model is considered representative of the one-dimensional models developed only by the Advection /Dispersion relation, and the proposed method was investigated for the Arvand River. Observational data along the river were used to calibrate and validate the model. Materials and Methods Since the available and well-known one-dimensional computer programs are generally developed based on the 1D Advection-Dispersion model, they do not consider factors affecting salinity transport such as topography and river morphology heterogeneities known as storage areas. In such a way, these processes are not expressed by presenting the problem as a one-dimensional equation. In this research, in order to increase the accuracy of the simulation with well-known and available one-dimensional models a corrective solution is proposed. To compare the proposed modified method and the base ADE, at the first, the tidal and transboundary arvand river is modeled as a study area, which is a well-mixed river. The river's upstream and downstream boundary conditions were defined according to the available data in 2014. Manning's roughness parameters ranged from 0.017 to 0.033, and the dispersion coefficient was 285 m3/s according to previous studies. In order to apply the effect of stagnant areas in the modified equations, it is essential to determine the value of η for the river. This study uses three parameters of dispersion factor (a), dispersion exponent (b), and η by ant colony algorithm with the definition of 5 initial ants and 100 repetitions in Sehan station in the study area, Arvand river was optimized. The values of the estimated parameters are respectively η = 0.168, a = 273.4, b = 0.94. Therefore, in the modified model, corrections were made using the speed and effective dispersion coefficient as the modified Advection - Dispersion (MADE) method and considering variable dispersion coefficient depending on the flow's speed in the one-dimensional model. These changes were validated in the other two stations (Faw and Dweeb). Results and Discussion Based on this study results, increasing the parameter η caused the peak of the time series to rise and the river's travel time to decrease. The shortening of the water travel time in the river, although increases the dispersion coefficient due to the influence of the stagnant zone, the effect of this parameter on the time series of the simulated concentration is reduced. Like the observational data, the slope of falling and rising limbs is increased. By comparing the one-dimensional model in the two cases of using the effective dispersion coefficient and velocity and without it, the increase in accuracy in the simulation was determined at Sehan station - 123 km from the river formation site - after optimizing the coefficients with three statistical errors parameters. In addition, these changes at two other stations along the river with distances of 180 and 150 km from the river's source confirm this accuracy. For instance, the simulated and measured concentration in 12 months of the year by applying the optimized coefficients reaches the correlation coefficient (r) of 0.86 to 0.97 at a distance of 150 km from the upstream, and the root means square error (RMSE) improves 1.27 ppt. The remaining difference in the concentration estimation may be caused by the effect of other parameters or even the entry of agricultural runoff from the lands along the river. Conclusion Accurate estimation and simulation of concentration in river engineering have always been one of the environmental challenges. This research aimed to improve water quality simulation using one-dimensional model in well-mixed rivers. In order to increase the accuracy of the modeling and become closer to the actual conditions, correction factors such as considering the dead zones along the river have been suggested. Analysis showed that, on average, 16% of the surface of the Arvand River's cross-sections are stagnant areas, and the dispersion coefficient depends on the river's speed. These areas include bed dunes and meanderings of the river. The point that attracts attention is the tidal irrigation channels on the sides of the river. The results showed that in Sehan, Dweeb, and Faw stations, the root means square error decreases to 1.78, 1.27, and 0.84, respectively. Therefore, the modified 1D model estimated the concentration (in this study salinity) closer to the measurement data. In Dweeb and Sehan stations, the effect of dead zones such as river meandering is evident. Still, in Faw station, no significant improvement in the impact of stagnant zones was observed due to its proximity to the river mouth. The results of this research can be used for higher accuracy in one-dimensional water quality simulations and bringing the models closer to the natural conditions in rivers

    The Effect of Drought Stress on Morphological Characteristics and Yield Components of Medicinal Plant Fenugreek

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    Fenugreek (Trigonella foenum-graecum L.) is one of the oldest medicinal plants. In order to study water-stress effects on some morphological characteristics of fenugreek, an experiment was carried out in a strip plots based on randomized complete blocks design with three replicates, at Research Farm of Shahrekord University, Shahrekord, Iran, in 2010. The first factor was allocated to four water stress levels (irrigation after depletion of 20 (as control), 40, 60 and 80% of available soil moisture) and the second factor was six fenugreek landraces (Shiraz, Ardestan, Tirancheh, Yazd, Jahrom and Hindi). The results of ANOVA and comparison of means indicated that the effect of water stress was significant for all traits and variation was observed among landraces for all the studied characteristics. Mean comparison showed that drought stress reduced days to flowering, days to maturity, plant height and yield components (number of pods per plant, number of seeds per pod and 1000-kernel weight). It was also revealed that water stress caused reduction in biological yield (43%) and grain yield (42.3%) of all genotypes. Comparison between landraces indicated that maximum biological and grain yield belonged to Ardestan landrace. Assessment of cluster analysis showed that it was possible to classify Ardestan, Shiraz and Tirancheh as a single group having tolerance to water stress. In general, based on obtained results, the Ardestan landrace, with 22.37 g/plant, had the highest biological yield and Hindi landrace, with 73.83 days to maturity, was the most early-maturing one

    Effects of Foliar Application of Nitrogen, Zinc and Manganese on Yield, Yield Components and Grain Quality of Chickpea in Two Growing Seasons

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    To study the effects of foliar application of zinc, manganese and nitrogen on yield, yield components and grain quality of chickpea (Cicer arientinum L.) two experiments, one in autumn and the other in spring were conducted at Research Farm, Shahrekord University in 2009-2010 growing season each as a randomized complete block design with three replications. The treatments were foliar application of zinc sulfate, manganese sulfate zinc sulfate and manganese sulfate mixture, nitrogen and distilled water (as control). The results showed that planting season had a significant effect on plant height, 100-seed weight and seed yield. All measured traits, except plant height, increased in winter compared to spring growing season. This increase was more than 12% for grain yield. Foliar application of nutrients significantly affected seed yield and seed yield components. Foliar application of nitrogen, presumably, through significant increase in number of pods per plant, number of seeds per plant and 100-seed weight, increased the grain yield by 6.2% compared to control. Foliar application × planting season interactions were significant for plant height and number of pods per plant. Foliar application of nitrogen caused a significant increase in grain yield and protein content. Foliar application of zinc sulphate significantly increased Zn content of grains however it did not affect seed yield. In conclusion, foliar application of nitrogen could be suggested for increasing protein and grain yield in chickpea under similar conditions to that of the present study

    Regulation of the ascorbate-glutathione cycle in wild almond during drought stress

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    In wild species of almond (Prunus spp.), the activities of ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR), as well as the levels of ascorbate/glutathione pools and H2O2 were subjected to water deficit and shade conditions. After 60 days of water shortage, the species were subjected to a rewatering treatment. During water recovery, leaves exposed to sunlight and leaves under shade conditions of about 20–35% of environmental irradiance were sampled. After 70 days without irrigation, mean predawn leaf water potential of all the species fell from −0.32 to −2.30 MPa and marked decreases in CO2 uptake and transpiration occurred. The activities of APX, MDHAR, DHAR, and GR increased in relation to the severity of drought stress in all the wild species studied. Generally, APX, MDHAR, DHAR, and GR were down-regulated during the rewatering phase and their activities decreased faster in shaded leaves than in sun-exposed leaves. The levels in total ascorbate, glutathione, and H2O2 were directly related to the increase in drought stress and subsequently decreased during rewatering. The antioxidant response of wild almond species to drought stress limits cellular damage caused by reactive oxygen species during periods of water deficit and may be of key importance for the selection of drought-resistant rootstocks for cultivated almond

    Effect of exogenous hormones and chilling on dormancy breaking of seed of Asafoetida (Ferula assafoetida L.)

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    Asafoetida (Ferula assafoetida L.) is a medicinal plant with a problematic seed germination. Seeds of this plant have a long dormancy. The present research was carried out to investigate whether exogenous application of the hormones Gibberellic Acid (GA3), N6-furfurylaminopurine (kinetin) and 6-benzylaminopurine (BAP), alone or in combinations and chilling (for 0 or 28 days) could be used to alleviate the problem of dormancy. Germination was increased from 53.3% in a medium free of any hormones to 74.4% in a medium supplemented with 0.25 mg L-1 BAP. This was the only single hormone treatment giving a statistically significant increase in germination. Chilling increased germination from 37.5% (0 days of chilling) to 82.9% (28 days of chilling). Combining exogenous application of 0.25 mg L-1 BAP with 28 day chilling even gave more than 90% seed germination. Present findings suggest that seeds germination of Asafoetida can be greatly improved by combining chilling with BAP applicatio
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