87 research outputs found
Is salinity tolerance of rice lines concerned to endogenous ABA content or to the cellular ability for ABA synthesis under stress?
In this work we tested its putative relationship of Abscisic acid with the degree of tolerance to this abiotic stress. For this purpose, we have examined the responses of sensitive (IR29) and tolerant (IR651) varieties of indica rice (Oryza sativa L.) to a range of salinity (0 (control) and 90 mM NaCl. Shoot and root dry weight reduced and leaf Na concentration increased in response to salinity for both cultivars with a higher extent of sensitivity. Tolerance of IR29 to saline stress was generally improved by ABA treatment and leaves Na content reduced to the level of their respective control treatment. This ABA effect was evident in IR29 with low tolerance, as their ability to recover from stress increased up to seven fold. Independence of the saline treatment and the absolute endogenous leaf ABA content in sensitive variety was significantly more than that of the tolerant one. However, with stress, the increase in endogenous ABA synthesis was higher in tolerant than in sensitive varieties. These data together with those obtained by using fluridone, an inhibitor of ABA synthesis, suggest first of all, that there was differential sensitivity to ABA in the tolerant and sensitive leaves cultivars and enhanced concentrations at tolerant levels acted primarily to maintain root and shoot growth and secondly, the differences in the level of tolerance to saline stress is related to their different capacity of ABA synthesis under stress conditions.Key words: Abscisic acid, fluridone, Oryza sativa L., salinity
Appraisal of some physiological traits in two wheat cultivars subjected to terminal drought stress during grain filling
In a greenhouse experiment, two winter wheat (Triticum aestivum L.) varieties differing in post anthesis drought resistance, tolerant (cv. Zagros) and sensitive (cv. Marvdasht), were subjected to either well-watered (WW) or water-stressed (WS) from anthesis to maturity. All physiological parameters were affected by drought stress. Results show that water deficits enhanced the senescence by accelerating loss of leaf chlorophyll and soluble proteins and the loss was more in Marvdasht than Zagros. The net CO2 assimilation rate (PN) in flag leaves during water deficit displayed a strict correlation with the drought sensitivity of the genotypes and showed an early reduction in Marvdasht. The effect of drought on grain yield was primarily due to the significant reduction in grain weight, particularly in drought-sensitive Marvdasht. The results indicate that the main physiological factor associated with yield stability of Zagros under drought stress may be attributed to the capacity for chloroplast activity in the flag leaf, which apparently allows sustained PN of flag leaf during grain filling under drought stress.Keywords: Assimilate, chlorophyll, flag leaves, grain yield, wheat (Triticum aestivum L.
The Pedagogical Importance of Illustrations in Translated and Non-Translated Children’s Literature: An Intersemiotic Approach
In Children’s literature the text is almost always paired with vivid illustration to appeal to children more effectively. For young children, the pictorial code is a more direct means of communication than the verbal code. Such children will look at the pictures and tell the story in their own words. Also, children’s books are used for different purposes at different times. Children’s literature, for example, is a powerful means of educating children, through which they will be exposed to the set of behaviors deemed appropriate. That’s why illustrations in children’s stories are so important. Therefore, it is necessary to pay close attention to the illustrations and the relationships they hold with the linguistic texts of the story. The illustrations will serve better if they are educational. In the present study a number of translated and original Persian children story books were collected. All the books have illustrations which accompany the texts of the books. Then all the texts were studied carefully, analyzed and compared with their accompanying pictures (or illustrations). Each picture was analyzed based on its educational value. The results of the study revealed that there are significant differences in illustrations in translated and non-translated children story books
Range Optimization Using Trajectory Shaping Analysis Of A Surface-Launched Rocket.
This paper is outlined the design and flight performance ot an advanced Surface-Launched Rocket. Brief descriptions of the technologies in the rocket design, parameters driving the rocket design & performance, the rocket performance prediction and examples of maximizing flight performance are presented
An Intersemiotic Analysis of Pictures in Translated and Non-Translated Children’s Literature
Illustrations in books play a significant role in the development of the story by re-narrating the story which is also presented in linguistic forms (words). This process is a type of translation (intersemiotic) as proposed by Jacobson (2000). Also words being accompanied by illustrations help children to better involve in and understand the story. Therefore it is necessary to pay close attention to the illustrations and the relationships they hold with the linguistic texts of the story. There seems to be differences between English and Persian children’s story books in terms of illustrations. The study and investigation of the importance as well as strengths/weaknesses of illustrations in original Persian stories for children can help writer develop better strategies to organize their stories in both linguistic forms and illustrations. In the present study a number of translated and original Persian children story books were collected. All the books have illustrations which accompany the texts of the books. Then all the texts were study carefully, analyzed and compared with their accompanying pictures (or illustrations). Each picture was analyzed based on its relationship with the corresponding text. The results of the study revealed that there are significant differences in illustrations in translated and non-translated children story books
Digital Image Compression and Decompression Using Three Different Transforms and Comparison of Their Performance.
Data compression is an important tool in digital image processing to reduce the burden on the storage and transmission systems. The basic idea of data compression is
to reduce the number of the image pixel elements directly, say by sampling, or by using transforms and truncate the transformed image coefficients, so that the total number of
picture elements or its coefficients are reduced
Predicting Water Quality Distribution of Lakes through Linking Remote Sensing–Based Monitoring and Machine Learning Simulation
The present study links monitoring and simulation models to predict water quality distribution in lakes using an optimized neural network and remote sensing data processing. Two data driven models were developed. First, a monitoring model was established that is able to convert spectral images to TDS distribution. Moreover, a simulation model was developed to generate a TDS distribution map for unseen scenarios for which no spectral images are available. Outputs of the monitoring model were applied as the observations for training the simulation model. The Nash–Sutcliffe model efficiency coefficient (NSE) was utilized in the system performance measurement of the models. Based on the results in the case study, the monitoring model was sufficiently robust to convert the operational land imager spectral bands of Landsat 8 to the TDS distribution map. The NSE was more than 0.6 for the monitoring model, which confirms the predictive skills of the model. Furthermore, the simulation model was highly reliable in generating the TDS distribution map of the lakes. Three tests were carried out to demonstrate the reliability of the model. When comparing the results of the monitoring model and simulation model, an NSE of more than 0.6 was found for all the tests. It is recommendable to apply the proposed method instead of conventional hydrodynamic models that might be highly time consuming for simulating water quality parameters distribution in lakes. Low computational complexity is the main advantage of the proposed method
Drought or/and Heat-Stress Effects on Seed Filling in Food Crops: Impacts on Functional Biochemistry, Seed Yields, and Nutritional Quality
Drought (water deficits) and heat (high temperatures) stress are the prime abiotic constraints, under the current and climate change scenario in future. Any further increase in the occurrence, and extremity of these stresses, either individually or in combination, would severely reduce the crop productivity and food security, globally. Although, they obstruct productivity at all crop growth stages, the extent of damage at reproductive phase of crop growth, mainly the seed filling phase, is critical and causes considerable yield losses. Drought and heat stress substantially affect the seed yields by reducing seed size and number, eventually affecting the commercial trait ‘100 seed weight’ and seed quality. Seed filling is influenced by various metabolic processes occurring in the leaves, especially production and translocation of photoassimilates, importing precursors for biosynthesis of seed reserves, minerals and other functional constituents. These processes are highly sensitive to drought and heat, due to involvement of array of diverse enzymes and transporters, located in the leaves and seeds. We highlight here the findings in various food crops showing how their seed composition is drastically impacted at various cellular levels due to drought and heat stresses, applied separately, or in combination. The combined stresses are extremely detrimental for seed yield and its quality, and thus need more attention. Understanding the precise target sites regulating seed filling events in leaves and seeds, and how they are affected by abiotic stresses, is imperative to enhance the seed quality. It is vital to know the physiological, biochemical and genetic mechanisms, which govern the various seed filling events under stress environments, to devise strategies to improve stress tolerance. Converging modern advances in physiology, biochemistry and biotechnology, especially the “omics” technologies might provide a strong impetus to research on this aspect. Such application, along with effective agronomic management system would pave the way in developing crop genotypes/varieties with improved productivity under drought and/or heat stresses
Transcriptome profiling analysis for two Tibetan wild barley genotypes in responses to low nitrogen
the Role of Leadership Styles, Organizational Culture and Organizational Trust on Organizational Silence (Case Study: Payame Noor University of Kermanshah Province)
The purpose of this research is the role of leadership styles, organizational culture and organizational trust on organizational silence in Payame Noor University of Kermanshah. The current research is applied in terms of its purpose and is descriptive-survey in terms of its nature and method. The statistical population of this research is 380 employees (scientific and administrative) of Payame Noor University of Kermanshah which 191 people were selected as the sample using Cochran formula. Data collection tools, Clarke leadership styles questionnaire (2002), Robbins organizational culture (1996), and organizational trust Alonen et al. (2008) and organizational silence Saeedipour and Akbari (1396). Validity (content, convergent, divergent) and reliability (factor load, composite reliability coefficient, Cronbach's alpha coefficient). The questionnaires indicate that the measuring instruments have a good validity and reliability. The results of the hypothesis test by SMART-PLS software and using t-test statistics and path coefficients (β) showed that leadership styles had a strong, direct and significant effect on organizational culture, organizational trust and organizational silence, respectively. Has a moderate, direct and non-significant effect, and has a weak, direct, and indirect impact. Organizational culture has a moderate, direct and significant effect on organizational trust and organizational silence, and has a moderate, direct and indirect indirect and significant effect, respectively. Also, organizational trust has a direct, significant effect on organizational silence, from organizational culture Can play the role of mediation in influencing leadership styles on organizational trust and organizational silence. Also, organizational trust can play a role as an intermediary variable in influencing leadership styles on organizational silence and organizational culture
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