The influence of mutation on population dynamics in multiobjective genetic programming

Using multiobjective genetic programming with a complexity objective to overcome tree bloat is usually very successful but can sometimes lead to undesirable collapse of the population to all single-node trees. In this paper we report a detailed examination of why and when collapse occurs. We have used different types of crossover and mutation operators (depth-fair and sub-tree), different evolutionary approaches (generational and steady-state), and different datasets (6-parity Boolean and a range of benchmark machine learning problems) to strengthen our conclusion. We conclude that mutation has a vital role in preventing population collapse by counterbalancing parsimony pressure and preserving population diversity. Also, mutation controls the size of the generated individuals which tends to dominate the time needed for fitness evaluation and therefore the whole evolutionary process. Further, the average size of the individuals in a GP population depends on the evolutionary approach employed. We also demonstrate that mutation has a wider role than merely culling single-node individuals from the population; even within a diversity-preserving algorithm such as SPEA2 mutation has a role in preserving diversity

The Application of Leechs Politeness Maxims in Shakespeares The Merchant of Venice

This study aims to investigate Shakespeares The Merchant of Venice in light of the application of Leechs politeness maxims. The study uses a qualitative method in analyzing the utterances of the major characters in the play; Shylock, Antonio and Bassanio, since most of the events within the play focus on their demands, personalities and behaviors. The purpose of this study is to reveal the degree of politeness reflected in the characters speeches. 17 extracts from Act 1 scene 3 (a street in Venice) and 6 extracts from Act 4 scene 1 (the court scene) are explored due to their importance in the plot development. In light of the analysis, some of the factors are highlighted according to their significant role in determining the use of politeness or impoliteness strategies. These factors are power, psychological aspects, personal values, irony principle, social status and religion. The study also examines the way in which the six maxims are employed in the extracts. To conclude, politeness strategies can be used to reveal much about peoples identities, values and psychology

Long-Term Water Quality Monitoring at an Industrial Site on the Northern Gulf of Aqaba, Red Sea

The present study focuses on seawater samples collected monthly, for 12 years (June 1998 to December 2010), within the framework of the sustainable monitoring program in front of the Industrial Complex (IC) Aqaba Jordan. In situ measurements of temperature, salinity, pH and dissolved oxygen have been recorded, for three different depths, at six different stations. Also, samples have been collected and analyzed for inorganic nutrients, fluoride and sulfate. The data collected, when compared with the offshore waters, showed the dominance of natural Aqaba seawater conditions for most variables throughout the year. Phosphate concentrations were slightly higher in some sampling events. This, however, did not exert any considerable effect on the environmental quality of the seawater, mainly because anthropogenic phosphate reaching the sea does with the help of the wind in very limited amounts and insoluble form. Also, phosphate is not the primary productivity limiting nutrient in the waters of theGulf of Aqaba

A simple method to assess walkability around metro stations

The ability to walk or ride a bike safely to and from metro stations is essential to the success of any metro service, especially for car users switching to the service. The main purpose of this study is to develop and apply a simple method to assess, compare, and rank walkability around different metro stations, with a priority order and specific recommendations for improvements. The proposed method depends on extracting different walkability variables in the catchment areas around metro stations. Three catchment areas around three proposed metro stations in the emerging city of Doha, Qatar were investigated using the proposed method to demonstrate its usefulness. The method was successful in comparing and ranking the different catchment areas, in addition to identifying priority areas for walkability enhancements in each area. This method is simple and can benefit professionals, practitioners, and policy makers to make swift decisions for future corrective measures, and can also be used to evaluate changes over time. 2018 Inderscience Enterprises Ltd.Scopu

Remote Sensing Satellites Planning System

A Remote Sensing Satellites Planning system (RSSP) for satellite constellations is responsible for managing these satellites by assigning the imaging tasks to each satellite in the constellation such that the loads are balanced and the resources are well used. The proposed system can be used with heterogeneous constellations that consist of satellites whose different specifications, different orbits' types and/or different payload types. This problem is a combinatorial optimization NP-hard problem modeled in this paper as a Constraint Satisfaction Problem using the Constraint Programming Technique. The output plan is obtained using one of three objective functions (gain maximization, area maximization, and image quality maximization) using four search algorithms (simulated annealing, hill climbing, tabu search and late acceptance) and different planning horizons (one track, one day and one month)

Erythrocyte nanovesicles: Biogenesis, biological roles and therapeutic approach Erythrocyte nanovesicles

AbstractNanovesicles (NVs) represent a novel transporter for cell signals to modify functions of target cells. Therefore, NVs play many roles in both physiological and pathological processes. This report highlights biogenesis, composition and biological roles of erythrocytes derived nanovesicles (EDNVs). Furthermore, we address utilization of EDNVs as novel drug delivery cargo as well as therapeutic target. EDNVs are lipid bilayer vesicles rich in phospholipids, proteins, lipid raft, and hemoglobin. In vivo EDNVs biogenesis is triggered by an increase of intracellular calcium levels, ATP depletion and under effect of oxidative stress conditions. However, in vitro production of EDNVs can be achieved via hypotonic treatment and extrusion of erythrocyte. NVs can be used as biomarkers for diagnosis, monitoring of therapy and drug delivery system. Many therapeutic agents are suggested to decrease NVs biogenesis

Frequency-dependent magnetotransport and particle dynamics in magnetic modulation systems

We analyze the dynamics of a charged particle moving in the presence of spatially-modulated magnetic fields. From Poincare surfaces of section and Liapunov exponents for characteristic trajectories we find that the fraction of pinned and runaway quasiperiodic orbits {\em vs}. chaotic orbits depends strongly on the ratio of cyclotron radius to the structure parameters, as well as on the amplitude of the modulated field. We present a complete characterization of the dynamical behavior of such structures, and investigate the contribution to the magnetoconductivity from all different orbits using a classical Kubo formula. Although the DC conductivity of the system depends strongly on the pinned and runaway trajectories, the frequency response reflects the topology of all different orbits, and even their unusual temporal behavior.Comment: Submitted to PRB - 14 figure files - REVTEX tex

Prediction of Modulus of Rupture from Modulus of Elasticity for Some Egyptian Hardwoods

The MOE and MOR of 112 air-dry small, clear specimens (2 x 2 x 30 cm) of six species of hardwoods grown in Egypt were determined. Simple linear regression analysis revealed that MOR is highly correlated with MOE of Eucalyptus camaldulensis, Khaya senegalensis, Tamarix articulata and Casuarina spp. However, the "r" values for Jacaranda ovalifolia and Melia azedarach were not significant. In addition, covariance analysis showed that the six regressions equations have different slopes and Y-intercepts and therefore cannot be grouped. The only grouping was that between the regression lines of the first three species mentiones above.Introducing specific gravity in the regression equation did not result in improving the correlation coefficients, except in the case of Casuarina spp. Using specific gravity alone for predicting the MOR was found to be unreliable due to the relatively low "r" values obtained for the species except in the case of Casuarina spp

Influence of pravastatin chitosan nanoparticles on erythrocytes cholesterol and redox homeostasis: An in vitro study

AbstractThe objective of this study was to develop and characterize chitosan nanoparticles (CSNPs) to increase efficacy of pravastatin (PR) on erythrocytes redox status. CSNPs and PR loaded CSNPs (PRCSNPs) were prepared by ionic gelation method. The particle size, zeta potential, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) and X-ray diffraction (XRD) were used to investigate physicochemical characters of the prepared nanoparticles. The present results revealed that CSNPs and PRCSNPs have nanosize about 90nm with spherical shape, positive zeta potential and prolonged PR release. Moreover, DSC and FTIR indicated no chemical interactions between PR and CS. In vitro studies revealed that, erythrocyte uptake of PR from PRCSNPs was higher than free PR solution. Incubation of erythrocytes in high cholesterol plasma, hypercholesterolemia (HC), increases membrane cholesterol, erythrocyte hemolysis, oxidized glutathione (GSH), protein carbonyl (PCC), and malondialdeyhe (MDA). However, HC significantly decreases PR uptake by erythrocytes, superoxide dismutase (SOD), glutathione peroxidase (GPx) catalase (CAT) activities, reduced GSH and nitrite levels compared to control. By contrast, treatment of HC with PR plus CS as free drug or nanostructure formula keeps the measured parameters at values near that of control. The effect of CSNPs and PRCSNPs on redox status of erythrocytes was more prominent than free drugs. In conclusion, PRCSNPs are promising drug carrier to deliver PR into erythrocytes, moreover, PRCSNPs possess promising characteristics with high biological safety for treatment of HC induced disruption of redox homeostasis