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An overview is presented of recent advances in our knowledge of candidate proteins that regulate various physiological and biochemical processes underpinning plant adaptation to saline conditions. Salt stress is one of the environmental constraints that restrict plant distribution, growth and yield in many parts of the world. Increased world population surely elevates food demands all over the globe, which anticipates to add a great challenge to humanity. These concerns have necessitated the scientists to understand and unmask the puzzle of plant salt tolerance mechanisms in order to utilize various strategies to develop salt tolerant crop plants. Salt tolerance is a complex trait involving alterations in physiological, biochemical, and molecular processes. These alterations are a result of genomic and proteomic complement readjustments that lead to tolerance mechanisms. Proteomics is a crucial molecular tool that indicates proteins expressed by the genome, and also identifies the functions of proteins accumulated in response to salt stress. Recently, proteomic studies have shed more light on a range of promising candidate proteins that regulate various processes rendering salt tolerance to plants. These proteins have been shown to be involved in photosynthesis and energy metabolism, ion homeostasis, gene transcription and protein biosynthesis, compatible solute production, hormone modulation, cell wall structure modification, cellular detoxification, membrane stabilization, and signal transduction. These candidate salt responsive proteins can be therefore used in biotechnological approaches to improve tolerance of crop plants to salt conditions. In this review, we provided comprehensive updated information on the proteomic data of plants/genotypes contrasting in salt tolerance in response to salt stress. The roles of salt responsive proteins that are potential determinants for plant salt adaptation are discussed. The relationship between changes in proteome composition and abundance, and alterations observed in physiological and biochemical features associated with salt tolerance are also addressed.

An overview is presented of recent advances in our knowledge of responses and mechanisms rendering adaptation to saline conditions in sorghum. Different strategies deployed to enhance salinity stress tolerance in sorghum are also pointed out. Salinity stress is a growing problem worldwide. Sorghum is the fifth key crop among cereals. Understanding responses and tolerance strategies in sorghum would be therefore helpful effort for providing biomarkers for designing greatest salinity-tolerant sorghum genotypes. When sorghum exposed to salinity, salinity-tolerant genotypes most probably reprogram their gene expression to activate adaptive biochemical and physiological responses for survival. The review thus discusses the possible physiological and biochemical responses that confer salinity tolerance to sorghum under saline conditions. Although it is not characterized in sorghum, salinity perceiving and transmitting signals to downstream responses via signaling transduction pathways most likely are essential strategy for sorghum adaptation to salinity stress. Sorghum has also shown to withstand moderate saline environments and retain the germination, growth, and photosynthetic activities. Salinity-tolerant sorghum genotypes show the ability to exclude excessive Na+ from reaching shoots and induce ion homeostasis. Osmotic homeostasis and ROS detoxification are also evident as salinity tolerance strategies in sorghum. These above mechanisms lead to re-establishment of cellular ionic, osmotic, and redox homeostasis as well as photosynthesis efficiency. It is noteworthy that these mechanisms act individually or co-operatively to minimize the salinity hazards and enhance acclimation in sorghum. We conclude, however, that although these responses contribute to sorghum tolerance to salinity stress, they seem to be not adequate at higher concentrations of salinity, which agrees with sorghum ranking as moderately salinity-tolerant crop. Also, some of these tolerance strategies reported in other crops are not well studied and documented in sorghum, but most probably have roles in sorghum. Further improvement in sorghum salinity tolerance using different approaches is definitely necessary to meet the requirements of its harsh production environments, and therefore, these approaches are addressed.

Metal pollution nowadays has become one of the most serious environmental challenges. Unfortunately, heavy metals are not biodegradable. Plants evolve different strategies to cope with metal toxicity or to maintain the level of essential metals within the physiological range. Phytoremediation is a special strategy used to clean up toxic metals from the environment components by using specially selected or genetically engineered plants and their associated microbes. There are several strategies explored to remediate soils contaminated with heavy metal including phytoextraction, phytostabilization, phytovolatilization, and rhizofiltration. Redox potential is one of various crucial factors regulating phytoremediation strategy. Redox process reduces heavy metal ions to a lower oxidation state to become less bioactive. In addition, the importance of the redox systems comes from the fact that redox potential at cellular or whole plant level can be used as an indicator of soil health during remediation processes. This chapter therefore presents an overview on the redox defense mechanisms that overcoming oxidative damage in heavy metal stressed plants, thus enhancing phytoremediation capacity. It also discusses the molecular mechanisms involved in metal tolerance and the biotechnological approaches to improve phytoremediation efficiency. We believe that the knowledge gathered here could participate in the biotechnological improvement of phytoremediation efficiency and hence reduces metal toxicity to a marginal level.

Abiotic stresses are major threats influencing crop growth and production globally. Abiotic stresses can cause several cellular dysfunctions, and some of them are beneficial and required for stress tolerance enhancement. Compatible solute accumulation is one of these changes, and among them proline (Pro) overproduction is a physiological response commonly found in plants exposed to various abiotic stresses. Pro overproduction has been proposed to correlate with stress resistance in many plants. Pro implication in stress tolerance mechanism is supported by the observations that exogenous supply and genetic manipulation of metabolic pathways associated with Pro biosynthesis have been beneficial in enhancing stress tolerance in many plant species under different stresses. Pro improves stress tolerance via acting as a stress-related signal influencing adaptive responses, osmotic adjustment mediator, and molecular chaperone to stabilize subcellular structures, scavenging reactive oxygen species (ROS), acting as a metal chelator, serving as a nitrogen/carbon source for cells under stress conditions and after stress relief, maintaining cytoplasmic pH and hence alleviating its acidosis, triggering gene expression, and buffering cellular redox potential. Pro actual role in conferring stress tolerance is, however, still a matter of debate because there are several inconsistencies among published data. Also, Pro biosynthesis is dependent on a high diversity of regulation mechanisms, and even several of them are still largely obscure, which might exacerbate these discrepancies. Furthermore, the broad natural variation in Pro overproduction and its true role in metabolism of plants under stress conditions necessitate further research for better understanding of the reported variations. Despite the Pro beneficial roles observed under stress conditions, we believe that the often proposed relationship between Pro production and stress resistance may not be universal.

Salinity is a severe threat to agricultural production of over 80 million ha arable land area globally, especially in irrigated arid and semiarid regions. Understanding how plants cope with salt stress is therefore imperative. As the glycophytes and halophytes have salt tolerance mechanisms occur at the cellular level, understanding cellular mechanisms of salt tolerance becomes indispensable for crop improvement programs. Recent challenges such as climate change, increased world population, and demand for foods all over the globe aggravate the salinity impacts on plant production which urge scientists to understand deeply and fully the effects of salt stress on plants and how plants combat these effects. This chapter hence discusses the cellular mechanisms that may contribute to plant salt adaptation, namely, osmotic adjustment and osmolyte production, ion homeostasis and involvement of membrane transport systems, antioxidant defense systems and reactive oxygen species (ROS) detoxification, membrane lipids and proteins modeling to maintain membrane integrity, transport system activities, and signaling and cell wall modifications to regulate cell wall integrity, cell expansion, and stress sensing and signaling transduction. Disagreements among published data concerning these cellular mechanisms are also addressed. We believe that adopting one cellular mechanism for crop improvement programs or to understand plant adaptation to high salinity is not sufficient and premature. Alternatively, several genes must be pyramided to ensure the efficiency of any cellular salt tolerance trait, and testing hypotheses instead of just collecting repetitive data must be considered as promising feasible strategies to improve productivity in crop plants and unmask the puzzle of salt tolerance mechanism. Moreover, testing the results in realistic growth conditions such as the natural field saline conditions must be performed and focused in our future research in order to verify the underlying mechanism and its proposed functions in salt adaptation.

The radial artery (RA) access has been used to perform chronic total occlusion percutaneous coronary intervention (CTO PCI) with similar success and safety to CTO PCI using the common femoral artery (CFA) access. Distal transradial access in the anatomical snuffbox is a challenging new access with

Salinity stress is one of the most serious environmental factors limiting plant growth and productivity in large areas around the world. Priming approach was adopted to study the effect of glycinebetaine (GB) on enhancing salt tolerance of sensitive wheat cultivar (Gomeza 7). The caryopsis were primed in different concentrations of GB (25, 50, 100 mM) for 24 h, and then treated with or without 150 mM NaCl added to 1/4-modified Hoagland solution (MHS). The NaCl treatment lasted 38 d under natural environmental conditions. Salt stress reduced all growth parameters measured: fresh mass, dry mass, relative growth rate, for the shoots and roots, and relative water content (RWC). Salt imposition increased the level of Na+ and Cl−, and reduced Ca+2 and K+ levels in both shoots and roots. Exogenous application of GB alleviated the deleterious effects of salinity on growth and mineral contents, the effect was more pronounced with 25 mM GB. Priming of caryopsis in GB counteracted the increase in the plasma membrane (PM) permeability and increased the cell solute potential, which was decreased by salinity. GB priming also increased the GB and glutathione concentrations, and reduced proline (Pro) as well as lipid peroxidation. Salt tolerance enhancement by GB priming might be occurred through reduced lipid peroxidation, increased GB and glutathione resulting in PM protection, and eventually ion homeostasis. The study is a valuable confirmation for enhancing salt adaptation via GB priming, which is of general interest for agriculture practices.

The PM is believed to be one facet of the cellular mechanisms involved in adaptation to saline conditions. Alterations in the PM components in response to salinity are therefore anticipated to contribute to plant salt tolerance. The review provides a comprehensive overview of the recent findings describing the crucial roles of the PM components in plant acclimation to salt stress. The responses of the PM proteins and lipids to salinity in contrasting species/cultivars were therefore discussed. The relationship between alterations in the lipids and proteins of the PM and tolerance to salt stress is also addressed. Several lines of evidence were presented demonstrating correlation of modifying the PM composition with adaptation of plants to high salinity. Even if contradictory results have been observed, the roles of the PM lipids and proteins appeared to be of great importance for tolerance to high salinity. Despite the promising results, more research should be carried out at the molecular level to further evaluate the roles of some of the PM components in salt tolerance.

Salt stress represents one of the environmental challenges that drastically affect plant growth and yield. Evidence suggests that glycophytes and halophytes have a salt tolerance mechanisms working at the cellular level, and the plasma membrane (PM) is believed to be one facet of the cellular mechanisms. The responses of the PM transport proteins to salinity in contrasting species/cultivars were discussed. The review provides a comprehensive overview of the recent advances describing the crucial roles that the PM transport systems have in plant adaptation to salt. Several lines of evidence were presented to demonstrate the correlation between the PM transport proteins and adaptation of plants to high salinity. How alterations in these transport systems of the PM allow plants to cope with the salt stress was also addressed. Although inconsistencies exist in some of the information related to the responses of the PM transport proteins to salinity in different species/cultivars, their key roles in adaptation of plants to high salinity is obvious and evident, and cannot be precluded. Despite the promising results, detailed investigations at the cellular/molecular level are needed in some issues of the PM transport systems in response to salinity to further evaluate their implication in salt tolerance.

There is evidence that the plasma membrane (PM) permeability alterations might be involved in plant salt tolerance. This review presents several lines of evidence demonstrating that PM permeability is correlated with salt tolerance in plants. PM injury and hence changes in permeability in salt sensitive plants is brought about by ionic effects as well as oxidative stress induced by salt imposition. It is documented that salinity enhances lipid peroxidation as well as protein oxidative damage, which in turn induces permeability impairment. PM protection, and thus retained permeability, in tolerant plants under salt imposition could be achieved through increasing antioxidative systems and thereby reducing lipid peroxidation and protein oxidative damage of PM. It appears that specific membrane proteins and/or lipids are constitutive or induced under salinity, which may contribute to maintenance of membrane structure and function in salt tolerant plant species. Furthermore, protecting agents (e.g., glycinebetaine, proline, polyamines, trehalose, sorbitol, mannitol) accumulated in salt tolerant species/cultivars may also contribute to PM stabilization and protection under salinity. Based on the presented evidence that PM permeability correlates with plant salt tolerance, we suggest that PM permeability is an easy and useful parameter for selection of genotypes of agriculture crops adapted to salt stress.

Salt stress is one of the environmental threats that have devastating impacts on plant distribution, growth and production. Different plants are believed to have salt tolerance mechanisms that occur at the cellular level. One facet of the cellular mechanisms of adaptation to salinity stress is to accumulate either inorganic and/or organic solutes. Glycinebetaine (GB), as well as other organic solutes, has been referred to as compatible solutes, for the reason that they are innocent with essential biochemical reactions even at high concentrations. GB has been assumed to be involved in osmotic adjustment and/or osmoprotection of cellular functional macromolecules and, hence, can improve tolerance to saline conditions. However, the exact mechanism and direct evidences for such correlative data are still lacking despite many attempts to improve growth under saline conditions by exogenous application as well as genetic engineering of metabolic pathways involved in metabolism of GB. Despite the enormous amount of information accumulated in this regard, the exact function of GB in the adaptation to saline environments is not fully clear to this point, and even GB functions have been argued. Because of that, inconsistencies exist in the published data regarding GB accumulation and functions under salt stress. In this review, we provide an update on evidence supporting each of these arguments to reassess how GB affects plant growth and physiological traits under salt imposition, and whether its effects correlate with salt tolerance.

Background XAGE-1b is shown to be overexpressed in lung adenocarcinoma and to be a strong immunogenic antigen among non-small cell lung cancer (NSCLC) patients. However, 3D structure of XAGE-1b is not available and its confirmation has not been solved yet. Methods Multiple sequence alignment was run to select the most reliable templates. Homology modeling technique was performed using computer-based tool to generate 3-dimensional structure models, eight models were generated and assessed on basis of local and global quality. Immune Epitope Database (IEDB) tools were then used to determine potential B-Cell epitopes while NetMHCpan algorithms were used to enhance the determination for potential epitopes of both Cytotoxic T-lymphocytes and T-helper cells. Results Computational prediction was performed for B-Cell epitopes, prediction results generated; 3 linear epitopes where XAGE-1b (13-21) possessed the best score of 0.67, 5 discontinuous epitopes where XAGE-1b (40-52) possessed the best score of 0.67 based on the predicted model of the finest quality. For a potential vaccine design, computational prediction yielded potential Human Leukocyte Antigen (HLA) class I epitopes including HLA-B*08:01-restricted XAGE-1b (3-11) epitope which was the best with 0.2 percentile rank. Regarding HLA Class II epitopes, HLA-DRB1*12:01-restricted XAGE-1b (25-33) was the most antigenic epitope with 5.91 IC50 value. IC50 values were compared with experimental values and population coverage percentages of epitopes were computed. Conclusions This study predicted a model of XAGE-1b tertiary structure which could explain its antigenic function and facilitate usage of predicted peptides for experimental validation towards designing immunotherapies against NSCLC.

More than one third of the world's irrigated lands are affected by salinity, which has great impact on plant growth and yield worldwide. Proline accumulation under salt stress has been indicated to correlate with salt tolerance. Exogenous application as well as genetic engineering of metabolic pathways involved in the metabolism of proline has been successful in improving tolerance to salinity. Correlation between proline accumulation as well as its proposed roles and salt adaptation, however, has not been clearly confirmed in several plant species. In addition, the studies relating proline functions and plant salt tolerance are always carried out in growth chambers, and are not successfully verified in field conditions. Further, plant salt tolerance is a complex trait, and studies based solely on proline accumulation do not adequately explain its functions in salinity tolerance, and thus it is difficult to interpret the discrepancies among different data. Moreover, several reports indicate that Pro role in salt tolerance is a matter of debates, as whether Pro accumulation has adaptive significance or is a consequence of alterations in cellular metabolism induced by salinity. As no consensus is obtained on the exact roles of proline production, proline exact roles in the adaptation to saline environments is therefore still lacking and is even a matter of debates. It is obvious that comprehensive future research is needed to establish the proline exact mechanism by which it enhances plant salt tolerance. We propose, however, that proline might be essential for improving salinity tolerance in some species/cultivars, but may not be relevant in others. Evidence supporting both arguments has been presented in order to reassess the feasibility of the proposed roles of Pro in plant salt tolerance mechanism.

Increasing expansion of power systems and grids are accompanied nowadays by innovation in smart grid solutions to maintain systems stability. This paper proposes an intelligent wide area synchrophasor based system (IWAS) for predicting and mitigating transient instabilities. The IWAS incorporates artificial neural networks (ANN) for transient stability prediction. The ANN makes use of the advent of phasor measurements units (PMU) for real-time prediction. Coherent groups of generators-which swing together-is identified through an algorithm based on PMU measurements. A remedial action scheme (RAS) is applied to counteract the system instability by splitting the system into islands and initiate under frequency load shedding actions. The potential of the proposed approach is tested using New England 39 bus system.

Background: Heavy metals are major environmental pollutant when they present in high concentration in soil and have toxic effects on growth and development of plants. Industrial activities result in heavy metal pollution of large areas of land, which greatly affects natural vegetation. Understanding the mechanism of how plants combat heavy metals adverse effects is hence of great importance. Materials and Methods: Two different localities were chosen; one locality was in the vicinity of gypsum factory and the other one was 25 km away from the factory. Two Zygophyllum species (Z. album and Z. coccineum) were naturally grown in the studied areas. The effects of soil heavy metal stress on shoot heavy metal concentrations, lipid peroxidation, antioxidant enzyme activities and the root plasma membrane (PM) lipid composition were analyzed. Results: Heavy metal concentrations and Lipid peroxidation increased in the shoot of both species grown in the polluted area. The activities of ascorbate oxidase (ASO), guaiacal peroxidase (GPX), ascorbate peroxidase (APX) and superoxide dismutase (SOD) were increased whereas these of catalase (CAT) were decreased in both species under the polluted conditions. PM total lipids, phospholipids, glycolipids and sterols were decreased in Z. album and Z. coccineum as a result of the polluted soil. Heavy metal stress increased phosphatidylethanolamine (PE) and decreased phosphatidylinositol (PI) and phophatidylglycerol (PG), with no significant change in phosphatidylcholine (PC) in the root PM of both species. Phosphatidylserine (PS) decreased in the PM of Z. album whereas it increased in the PM of Z. coccineum under the pollution conditions. Heavy metal stress changed the composition and concentration of fatty acids of the root PM, resulting in increased sat/unsat ratio of both species. Conclusion: the results suggest that efficient antioxidant machinery and favorable PM lipid homeostasis are important to enable Zygophyllum species to withstand the prevailing heavy metal stress.

The coordination of directional overcurrent relays (DOCR) is treated in this paper using particle swarm optimization (PSO), a recently proposed optimizer that utilizes the swarm behavior in searching for an optimum. PSO gained a lot of interest for its simplicity, robustness, and easy implementation. The problem of setting DOCR is a highly constrained optimization problem that has been stated and solved as a linear programming (LP) problem. To deal with such constraints a modification to the standard PSO algorithm is introduced. Three case studies are presented, and the results are compared to those of LP technique to demonstrate the effectiveness of the proposed methodology.

Salt stress is a major environmental threat influencing crop growth and yield. The plasma membrane (PM) is believed to be one facet of the cellular mechanisms of salt adaptation. Choline priming has been reported to enhance salt tolerance of the sensitive wheat cultivar used in this work. The study was, therefore, undertaken to examine whether changes in the PM lipids will participate in choline-improved salt tolerance. The caryopses were primed in choline chloride (0, 5 and 10 mM) for 24 h. They were then germinated in sand for 10 days, watered with 1/4-strength modified Hoagland solution (MHS). The seedlings were grown in the sand, watered with MHS containing 150 mM NaCl for 3 weeks. Root PM was isolated by two-phase partitioning method and its lipid classes were determined. Choline maintained the PM total lipids, sterol and phospholipids, which were altered by NaCl. The PM sterols/phospholipids ratio was decreased by NaCl, whereas choline retained this ratio. Salt stress reduced the PM unsaturated fatty acids while increased its saturated fatty acids. Choline alleviated PM unsaturated/saturated ratio reduction. NaCl declined the PM phosphatidylcholine (PC), phosphatidylglycerol (PG) and diphosphatidylglycerol (DPG) whereas increased phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylethanolamine (PE). Choline decreased PS and PE, while increased PC level. The PM cholesterol, campesterol and β-sitosterol were increased while stigmasterol was declined under NaCl. Choline increased stigmasterol whereas decreased cholesterol and campesterol. The alterations in the PM lipids were discussed in relation to choline-enhanced salt tolerance.

A new technique for estimating the frequency contents in a signal is applied to power systems. The technique uses two sets of measured samples: samples from the signal itself and samples from a filtered signal obtained by passing the original signal through a continuous-time filter. The estimates of the frequencies contained in the signal are obtained from the eigenvalues of the generalized eigenproblem of two matrices formed from the two sets of samples. The technique assumes estimating multiple sinusoids which makes it suitable in cases with large harmonic distortion. Results show that by the proper choice of the sampling time, the eigenproblem condition is improved such that accurate estimates become attainable in case of noise. Further improvement in the estimate accuracy is achievable by utilizing correlated samples. The technique is also applied to estimating varying frequency.

Glycophytes and halophytes are believed to have salt tolerance mechanisms that occur at the cellular level. One facet of the cellular mechanisms concerns the elements of the protoplasm. Variations in the response of plasma membrane permeability in salt sensitive and tolerant genotypes to salinity are explained by differences in composition and/or structure of the plasma membrane. Changes in plasma membrane lipid composition are evident upon salt exposure. Changes in protein–lipid interactions may also be involved in plasma membrane permeability variations. Agents that accumulate under salinity and have membrane protective function mitigate cellular alterations brought about by salinity-induced plasma membrane disruption. It is obvious that salt adaptation mechanisms depend on preservation of plasma membrane integrity under salt stress. Cytoplasmic viscosity responds differently to salt imposition in genotypes contrasting in salt tolerance, reflecting differences in cytoplasm structure and composition. Results also support a cytoplasmic basis for salt tolerance. Data indicate absence of association of osmotic adjustment and adaptation to salinity. More information is needed to interpret the response of cytoplasmic streaming to salinity. Assays of protoplasmic qualities, such as cell membrane permeability and cytoplasmic viscosity, will provide an easy and fast test for screening relatively large numbers of cultivars for salt tolerance.

Evidence indicates that plant salt tolerance operates at a cellular level. Commonly proposed cellular mechanisms include ion sequestration in vacuoles or ion exclusion at plasma membranes. Plasma membrane ATPase and vacuolar ATPase and pyrophosphatase are proton pumps that provide an energy source for transport of ions across the plasma membrane and tonoplast, respectively. Membrane Na + /H + antiporters take advantage of the proton gradient formed by these pumps to exchange Na + for H + across a membrane. Therefore, activity and expression of these proton pumps and Na + /H + antiporters are investigated in numerous plant species under saline environment. In this review, information is presented on responses of tonoplast and plasma membrane ATPases and Na + /H + antiporters to salinity. Inconsistencies exist in some of the information and this may be due to differences in cultivars, experimental conditions, salt level used and plant age. Correlation between increased activity and expression of these transport proteins and adaptation to salinity is proposed, although this correlation is based on untested hypotheses. This precludes a general conclusion to be drawn concerning the involvement of membrane transport systems in plant salt tolerance. It is obvious that further extensive studies are needed in this area.

In this paper, the authors introduce two new heuristic techniques for reactive power compensation in radial distribution feeders. The methods can be considered as generalization ideas that emerged from recent heuristic search strategies and lead to better results. The methods formulae are derived and the techniques are applied to three feeders. Results of the proposed approaches are compared with previous methods to show the superiority of the proposed methods. To show the closeness or remoteness from the optimal solution after implementing these methods, a new algorithm using the variational technique, is presented to obtain the optimal capacitor allocation according to available standard sizes of capacitors.

Caryopses of a salt sensitive wheat cultivar (Triticum aestivum L. cv. Giza 163) were presoaked in 2.5 mM putrescine (Put), 5 mM spermidine (Spd) or 2.5 mM spermine (Spm) for 24 h and then subjected to 150 mM NaCl added to the growth medium for 15 d. Effects of NaCl and polyamines (PAs) on plasma membrane (PM) lipids, phospholipids, fatty acids, and free sterols were determined. NaCl treatment caused a decrease in total phospholipids, increase in saturated fatty acids and altered distribution of sterols and phospholipids. NaCl also induced increase in sterol/phospholipid ratio. PAs treatments (particularly Put and Spd) counterbalanced the NaCl deleterious effects on PM lipids.

A number of nitrogen containing compounds (NCC) accumulate in plants exposed to salinity stress. The most frequently accumulating NCC include amino acids, amids, imino acids, proteins, quarternary ammonium compounds (QAC) and polyamines. The specific NCC that accumulate in saline environment vary with the plant species. Osmotic adjustment, protection of cellular macromolecules, storage form of nitrogen, maintaining cellular pH, detoxification of the cells, and scavenging of free radicals are proposed functions for these compounds under stress conditions. NCC accumulation is usually correlated with plant salt tolerance, even though this correlation is based on untested hypotheses.

Wheat seedlings of a salt tolerant cultivar were grown hydroponically in presence and absence of 100 mM NaCl. Roots were harvested, and the plasma membrane (PM) fraction was purified. PM ATPase required a divalent cations for activity (Mg > Mn > Ca > Co > Zn > Ni > Cu), and it was further stimulated by monovalent cations (K > Rb > NH4 > Li > choline > Cs). The pH optima were 6.0 and 5.6 in absence and presence of 25 mM KCI, respectively. The enzyme was sensitive to vanadate and DCCD but insensitive to azide, oligomycine and nitrate. The enzyme displayed a high preference for ATP but was also able to hydrolyze other nucleotide tri- and diphosphates. The enzyme activity showed a simple Michaelis-Menten kinetics for the substrate Mg2+-ATP in both control and salt exposed roots. The polypeptide patterns of control and salt stressed PM fractions, detected by SDS-PAGE, were very similar. NaCl substantially reduced the PM ATPase specific activity, whereas it had little effect on the apparent K-m for Mg2+-ATP. Since the root PM ATPase of salt sensitive and resistant genotypes responded similarly to salinity stress, it seems unlikely that the mechanism of salt tolerance in wheat is primarily based on differences in PM ATPase characteristics.

To test the hypothesis that glycinebetaine (GB) or proline (Pro) may have a specific effect on the plasma membrane under salt stress, Allium cepa bulb scale inner epidermal cells were exposed for 3 h to 150 mM NaCl before or after GB or Pro treatments at different regimes. Two concentrations of GB or Pro were applied (50 or 100 mM). Plasma membrane permeability for individual intact cells and cell viability were measured to determine whether GB or Pro counteract the deleterious Na-induced alterations of the cell membrane. The NaCl treatment increased membrane permeability for urea and methylurea, and the number of cells with swollen protoplasm. It also enhanced cell death. GB or Pro added before, after, or simultaneously with NaCl significantly prevented Na-induced cellular alterations; exposure to GB or Pro prior to salt treatment had the greatest protective effect. GB was more effective as a membrane protectant than Pro. Both concentrations of GB or Pro had about the same effect suggesting high concentrations of GB or Pro are not required for the stabilization of the cell membrane. In conclusion, it is evident that cell membrane protection under salinity stress can be provided by GB or Pro thus leading to increased salt tolerance in plants.

Summary Winter wheat seedlings were grown in Hoagland nutrient solution with or without 100 mmol/L NaCl added. Plasma membranes from root cells were prepared by aqueous polymer two phase partitioning and the stimulation of plasma membrane ATPase activity by Mg 2+ and Ca 2+ was investigated. The enzyme was activated by Mg 2+ or Ca 2+ and Mg 2+ -ATPase was further stimulated by K + , whereas no such stimulation was observed with Ca 2+ -ATPase. Ca 2+ inhibited Mg 2+ -ATPase activity. pH optima for Mg 2+ - and Ca 2+ -ATPase activities were 6 and 5.6, respectively. ATPase activated by Mg 2+ was inhibited by vanadate and DCCD, while Ca 2+ -ATPase was less sensitive. ATP was the preferred substrate but other nucleotide tri- and diphosphates were also hydrolyzed by the plasma membrane ATPases. NaCl stress during growth had no major effect on the plasma membrane polypeptide components. Simple Michaelis-Menten kinetics were found when Mg 2+ - or Ca 2+ -ATP was used as substrate for both control and salt stressed roots. NaCI markedly reduced the V max of Mg 2+ - and Ca 2+ -ATPase activities while it had little effect on the apparent K m for Mg 2+ - or Ca 2+ -ATP. NaCl-induced reduction of V max of ATPase activity correlated with NaCl-altered plasma, membrane lipid composition and the role of the lipid environment in ATPase activity is discussed.

Summary This research was undertaken to study ionic (NaCl) and osmotic (mannitol) effects on the plasma membrane properties of inner epidermal cells of onion bulb scales. The influence of Ca2+ in counteracting the Na-induced cellular alterations was also studied. Cell membrane permeability for individual intact cells and cell viability were determined by the plasmolytic method, and lipid partiality was evaluated. Na+, and not mannitol, a) increased membrane permeability to urea, methylurea and ethylurea, b) decreased membrane partiality to lipid permeators, and c) increased the number of cells showing swollen protoplasm and number of dead cells. These effects resulting from Na+ were prevented by Ca+ when it was added either simultaneously with Na+ or separately after Na+ exposure. The results suggested that NaCl disrupted the plasma membrane structure, which is most probably initiated by the loss of its Ca2+. The protoplasmic swelling is a symptom of salt injury resulting from membrane disruption and subsequent Na+ accumulation in the cytoplasm, which was a consequence of water uptake. A deleterious effect of salinity on the plasma membrane must be attributed to ion toxicity rather than to osmotic stress.

One of the main characteristics of Smart Grids is self healing. This means that the grid should rapidly detects, analyzes, acts and restores for system instabilities. Controlled islanding is one of the techniques used to mitigate these system instabilities. System islanding is often considered as the final stage of power system defense plans. The goal is to preserve stable areas of the faulted power systems. This paper proposes a k-means technique of the Matlab Bioinformatics toolbox, which utilizes phasor measurement units (PMUs) outputs for identifying the generators coherent groups. The Bioinformatics technique is used for real time clustering of generators, which swing together, enabling splitting the system into islands much faster. Then it is applied to an actual grid (the Egyptian Power 218 bus system) as study systems. Compared to conventional coherency approaches, the bioinformatics technique is much simple in implementation and supports real time applications. (6 pages)

A highly enriched plasma membrane fraction was isolated by two phase partitioning from wheat roots (Triticum aestivum L. cv. Vivant) grown with and without 100 mM NaCl. The lipids of the plasma membrane fraction were extracted and characterized. Phosphatidylcholine and phosphatidylethanolamine were the major phospholipids with lesser amounts of phosphatidylinositol, phosphatidylglycerol, diphosphatidylglycerol, phosphatidic acid and phosphatidylserine. NaCl decreased the total phospholipids and the phosphatidylcholine portion of the plasma membranes. Salt treatment had no effect on total sterols and glycolipids, but the relative abundance of the free sterols was altered: cholesterol, stigmasterol and brassicasterol were significantly increased. Salt treatment resulted in an increase of the more planar/less planar ratio of the free sterols and in introduction of a double bond in the C-22 position in the side chain of stigmasterol and brassicasterol. The degree of fatty acid saturation of total phospholipids, phosphatidylcholine and phosphatidylethanolamine was increased after salt treatment. These lipid changes are discussed in relation to the salt tolerance mechanism.

Water permeability and cytoplasmic viscosity and straming were investigated in seedlings of two Hordeum vulgare cultivars differing in salt tolerance. Six-day-old seedlings were grown for 4 additional days in Hoagland solution with and without 100 mM NaCl added. Observations and measurements were made in subepidermal cells of teh coleoptile sing plasmolytic and centrifugation methods and recordings of the speed of movement of microsomes

Zircons from gabbro and plagiogranite in late Proterozoic ophiolites of the Arabian-Nubian Shield (ANS) in Egypt and the Sudan, as well as post-ophiolite granites have been dated using the stepwise evaporation method. Zircons from a plagiogranite in the Wadi Ghadir ophiolite, Eastern Desert of Egypt, yielded a mean 207Pb/206Pb age of 746±19 Ma, while a gabbro and diorite associated with the Abu Swayel ophiolite nappe ∼ 250 km southwest of Wadi Ghadir provided zircon 207Pb/206Pb ages of 729±17 and 736±11 Ma, respectively. Zircons from layered gabbro along the western margin of the Jabal Gerf ophiolite just north of 22°N were dated at 741±21 Ma, indistinguishable from the Wadi Ghadir and Abu Swayel results. A plagiogranite sample from the Onib ophiolite in the northern Red Sea Hills, Sudan, contains zircons with a 207Pb/ 206Pb age of 808±14 Ma, while granites which crosscut layered gabbro in this complex have zircon ages of 713±12 and 714±5 Ma respectively. The youngest granite at Onib was dated at 646±10 Ma and may reflect a phase of postaccretionary intraplate magmatism. Our zircon data document ocean crust generation between ∼ 810 and ∼ 730 Ma ago in the Nubian segment of the ANS, and the age data compare well with ophiolite generation in Saudi Arabia. However, some of our data cast doubt on large-scale correlations of suture belts between the Arabian and Nubian segments of the shield.

This paper proposes a real-time wide area protection system which incorporates artificial neural networks (ANN) for transient stability prediction. The ANN makes use of the advent of phasor measurements units (PMU) for real-time prediction. Rate of change of bus voltages and angles for six cycles after fault tripping and/or clearing is used to train a two layers ANN. Coherent groups of generators which swing together is identified through an algorithm based on PMU measurements. A remedial action scheme (RAS) is applied to counteract the system instability by splitting the system into islands and initiate under-frequency load shedding actions. The potential of the proposed approach is tested using New England 39-bus system.

In this paper, we describe a multimedia system for learning handwriting and pronunciation of alphabet letters or characters in different languages. This system provides haptic, audio and visual information according to the desired letter or character chosen by a user. Letters or characters from the Arabic, English, French, Japanese, and Spanish languages have been considered, although the system utilizes an XML-based schema to easily introduce new characters from another language.Three different modes of learning can be chosen in terms of haptic information: full guidance, partial guidance and a no guidance mode (no haptic feedback). The full guidance guides the user to follow a pre-recorded letter trajectory; whereas in partial guidance, a user can freely follow a letter-drawing path, but if the user deviates significantly, the system automatically brings him/her back to the optimal displayed path. The no guidance mode allows users to perform letter handwriting with only visual information. This system guides users to write a character, in a similar way as a teacher holds a student.s hand. Moreover, the character trajectory is displayed as the user is performing it. The results of this system evaluation show its potential as a virtual tool for learning handwriting.

Two contrasting maize (Zea mays L.) cultivars, i.e., Giza 2 (salt tolerant) and Trihybrid 321 (salt sensitive), were grown hydroponically to study NaCl effect (100 mM) on root plasma membrane (PM) lipid and protein alterations. The PM total sterols of Trihybrid 321 were decreased while that of Giza 2 was increased in response to salt. Salt imposition had no significant effect on PM total glycolipids and proteins of both cultivars. The PM total phospholipids were increased in Trihybrid 321 but it did not change significantly in Giza 2 after salinity stress. Molecular percentage of PM phospholipids and fatty acids of both cultivars was different in absence (0 mM) and presence (100 mM) of salt. The most abundant phospholipids in untreated Trihybrid 321 PM were phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylserine (PS), which changed into PG, PS, phosphatidylinositol (PI) and PC after salt treatment. However, the dominant phospholipids of the control PM of Giza 2 were PC, PE, PS and PG, which changed into PG, PE, PS and diphosphatidylglycerol (DPG) after salt imposition. Over 60% of the total fatty acids were saturated in control and salinized PM of both cultivars, which was increased after salt stress. The predominant fatty acid in the control and salinized PM of Trihybrid 321 was C18:1 and C17:0, respectively. However, in control and treated PM of Giza 2, the predominant fatty acid was C17:0 and C20:0, respectively. Qualitative and quantitative differences in PM protein patterns were found in both cultivars with and without salt. PM lipid changes enhanced membrane integrity, reflected in different ion accumulation (Mansour et al. 2005), and hence salt tolerance of Giza 2.

This paper introduces a microprocessor and wavelets based non communication relaying approach dedicated for on line six-phase power transmission lines fault detection, classification and faulted phase(s) selection. The approach uses wavelets for capturing the fault induced high frequency signals of currents and/or voltages. The captured high frequency signals are then used in conjunction with their energies to determine the faulted line and consequently for making a trip decision. For this purpose, a suitable wavelet for on line protection is chosen and tuned at a suitable band of frequencies. In order to investigate a real time performance of the introduced approach a microprocessor based laboratory prototype has been implemented and tested. The obtained results show that the approach is high speed in faulted phase(s) detection and insensitive for the fault inception angle, fault resistance, and line terminals.

The paper presents a new adaptive neural network based speed controller for the PMDC motor drive using an online tunable ANN control structure. The Proposed ANN regulator is tuned online using the backpropagation algorithm to minimize the actual motor speed error and current deviation. The performance of the ANN control algorithm is evaluated using a laboratory prototype drive system. The laboratory set-up comprises a PMDC motor fed from a DC supply or battery source via a pulse frequency modulation (PFM) MOSFET DC-DC chopper. The output from the ANN controller is used to regulate the duty cycle ratio (/spl alpha//sub D/) of the chopper converter. This scheme would be suitable for small urban type and factory forklift-EV drives using small size battery. The new online ANN rule-based assignment algorithm is used to update the ANN network weights and biases to ensure continuous effective dynamic response while keeping the motor inrush current under specified tolerable limits. The ANN controller can be assembled using available microchip controllers with EPROM software subroutines. The test results validate the robustness and flexibility of the proposed new ANN based speed controller under different load variations and excursions. Also, it shows good flexibility in dealing with any drive parametric uncertainties and sudden load variations. The paper presents digital simulation, laboratory testing and control validation results.

In this paper, a modified approach, based on the particle swarm optimizer (PSO) is presented and explained in detail. As a case study, this PSO technique is applied to the solution of the economic dispatch (ED) problem of thermal generating units. A piecewise quadratic function is used to represent the fuel cost of each generating unit. The B-coefficient method is used to model the transmission losses. A modification to the standard PSO algorithm is proposed to allow dealing with the power balance equality constraint. Unlike the traditional methods, this modification does not depend on penalizing the infeasible solutions using a pre-defined penalty function. The application of the proposed method to several case studies shows that it is applicable to large networks with multigenerating units including transmission losses with very promising results.

Wheat seedlings were grown hydroponically in absence and presence of 100 mM NaCl for 7 d. Cell membrane permeability to nonelectrolytes and water was determined by the plasmometric method for individual intact cells. NaCl increased membrane permeability to urea, methylurea and ethylurea and decreased permeability to water. Membrane lipid partiality was decreased by NaCl. The effects of NaCl on cell permeability parallel changes in the lipid composition of the plasma membranes induced by NaCl stress suggesting that nonelectrolyte permeability is a useful tool to probe alterations in the lipid matrix of the membrane.

In this paper, we introduce a new heuristic search strategy for reactive power compensation in radial distribution feeders. The method is a generalized technique of idea emerged from heuristic techniques and leads to better results. The method formulae are derived and the technique is applied to three feeders. Results of the proposed approach are compared with previous methods to show the superiority of the proposed method. To show the closeness or remoteness from the optimal solution after implementing these methods, a new algorithm using the variational technique is presented to obtain the optimal capacitor allocation according to available standard sizes of capacitors.

Six-phase power transmission has many advantages over three-phase transmission but the additional three phases complicate the fault analysis and the required protection. This paper introduces a wavelet-based protection approach for high-speed six-phase power transmission lines relaying. The approach is based on capturing the fault induced high frequency transients, superimposed on the power frequency currents, at a certain band of frequency. The transient energies of the captured signals are then determined and used for fault detection, classification and faulted phase(s) selection. Simulation studies show that the introduced approach is insensitive for the fault inception angle, fault resistance, and system source configuration.

The application of capacitors in electric power systems is intended for the control of power flow, improvement of stability, voltage profile management, power factor correction, and loss minimization. This paper presents a review of different solution methods found in the literature and is intended as a guide for those interested in the problem or intending to do additional research in the area. The assumptions made and brief descriptions of the solution methods are presented.