Design of Hydroxyapatite/Magnetite (HAP/Fe3O4) Based Composites Reinforced with ZnO and MgO for Biomedical Applications

Hydroxyapatite (HAP-- Ca 10(PO4 )6 (OH)2 ) is a biocompatible and bioactive material that is widely used for biomedical applications, especially in bone replacements. It has good load carrying capacity; however, it lacks antibacterial property. New bio-composites based on bovine hydroxyapatite doped with, magnetite iron oxide (HAP/ Fe3 O4 ) matrix reinforced with ZnO and MgO nanoparticles are proposed for biomedical applications that provide improved antibacterial activity with potential to be used in magnetic therapy. Microwave sintering was used to manufacture the composites. The microstructure evolution in these composites were studied by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). Density, microhardness, compressive strength of the composites was measured and compared along with their magnetic properties. Finite element analysis simulations were performed for the compression tests

Estimation of jumping distance using run-up velocity for male long jumpers

Background and Study Aim: The purpose of this study is to investigate the relationship between run-up velocity and jumping distance, and create a jumping distance estimation model that trainers may use practically for athletes at broad performance level. In a long jump, about ninety percent of the jumping distance is the athlete’s flying distance, and horizontal velocity, which has the highest effect on flying distance among biomechanical factors, is highly important in long jumps. Therefore, especially the velocity of the athlete in the last ten meters of run-up is considered to be the most important determinant of performance. Material and Methods: The research data was composed of 328 valid trials on 73 Turkish male long jumpers who were 18.7 (±2.8) years old. As a result of the correlation statistics obtained in this study, a linear regression model was formed between last-ten-meter running velocity and jumping distance, which was observed to have the highest correlation. Results: It was observed that the velocity for run-up in the last ten meters explained 76% of jumping distance. Based on the estimating equation, it may be stated that 0.1 m/s of increase in run-up velocity for male long jumpers will increase their jumping distance by 10.7 cm. Conclusions: It was observed that especially the velocity in the last 10 meters of run-up was one of the most significant predictors of performance, and the estimation model established using the value of run-up velocity, which had the strongest relationship, was able to make high-accuracy estimations for both low and high values. Keywords: long jump, velocity, estimation model

SEVERAL NEW INTEGRAL INEQUALITIES VIA K-RIEMANN–LIOUVILLE FRACTIONAL INTEGRALS OPERATORS

The main objective of this paper is to establish several new integral inequalities including k-Riemann – Liouville fractional integrals for convex, s-Godunova – Levin convex functions, quasiconvex, η-quasi-convex. In order to obtain our results, we have used classical inequalities as H¨older inequality, Power mean inequality and Weighted H¨older inequality. We also give some applications

Pricing Options in Incomplete Equity Markets via the Instantaneous Sharpe Ratio

We use a continuous version of the standard deviation premium principle for pricing in incomplete equity markets by assuming that the investor issuing an unhedgeable derivative security requires compensation for this risk in the form of a pre-specified instantaneous Sharpe ratio. First, we apply our method to price options on non-traded assets for which there is a traded asset that is correlated to the non-traded asset. Our main contribution to this particular problem is to show that our seller/buyer prices are the upper/lower good deal bounds of Cochrane and Sa\'{a}-Requejo (2000) and of Bj\"{o}rk and Slinko (2006) and to determine the analytical properties of these prices. Second, we apply our method to price options in the presence of stochastic volatility. Our main contribution to this problem is to show that the instantaneous Sharpe ratio, an integral ingredient in our methodology, is the negative of the market price of volatility risk, as defined in Fouque, Papanicolaou, and Sircar (2000).Comment: Keywords: Pricing derivative securities, incomplete markets, Sharpe ratio, correlated assets, stochastic volatility, non-linear partial differential equations, good deal bound

Exploring wind direction and SO2 concentration by circular-linear density estimation

The study of environmental problems usually requires the description of variables with different nature and the assessment of relations between them. In this work, an algorithm for flexible estimation of the joint density for a circular-linear variable is proposed. The method is applied for exploring the relation between wind direction and SO2 concentration in a monitoring station close to a power plant located in Galicia (NW-Spain), in order to compare the effectiveness of precautionary measures for pollutants reduction in two different years.Comment: 17 pages, 7 figures, 2 table

Window opening effects on structural behaviour of historical masonry Fatih Mosque

YesStructural walls of old historical structures are either blind or have openings for functional requirements. It is well known that in and out of plane responses of structural walls are affected by the size, locations, and arrangements of such openings. The purpose of this investigation is to study the window opening effects on static and seismic behaviors of historical masonry old mosques. Fatih Mosque, which was converted from a church, constructed in 914 in Trabzon, Turkey, is selected for this purpose. The mosque is being restored. Structural exterior walls of the mosque were made using stone and mortar materials. When the plaster on the walls was removed during the restoration, 12 window openings were found as blind on the exterior structural walls of the mosque. Within the scope of restoration works, it is aimed to open such blind windows. In order to investigate the effects of the window openings on the structural behavior of the mosque, 3D solid and finite elements models of the mosque with and without window openings are initially developed. The experimental dynamic characteristics such as frequency, damping ratio, and mode shapes of the current situation of the mosque, where some windows openings are blind, are determined using Ambient Vibration Testing. Then, the finite element model of the current situation of the mosque is updated using the experimental dynamic characteristics. The static and seismic time history analyses of the updated finite element model with and without window openings are carried out. Structural behaviors of the mosque with and without window openings are compared considering displacement and stress propagations

Metabolic determinants of cancer cell sensitivity to glucose limitation and biguanides

As the concentrations of highly consumed nutrients, particularly glucose, are generally lower in tumours than in normal tissues1,2, cancer cells must adapt their metabolism to the tumour microenvironment. A better understanding of these adaptations might reveal cancer cell liabilities that can be exploited for therapeutic benefit. Here, we developed a continuous flow culture apparatus (Nutrostat) for maintaining proliferating cells in low nutrient media for long periods of time and used it to undertake competitive proliferation assays on a pooled collection of barcoded cancer cell lines cultured in low glucose conditions. Sensitivity to low glucose varies amongst cell lines, and an RNAi screen pinpointed mitochondrial oxidative phosphorylation (OXPHOS) as the major pathway required for optimal proliferation in low glucose. We found that cell lines most sensitive to low glucose are defective in the upregulation of OXPHOS normally caused by glucose limitation as a result of either mtDNA mutations in Complex I genes or impaired glucose utilization. These defects predict sensitivity to biguanides, anti-diabetic drugs that inhibit OXPHOS3,4, when cancer cells are grown in low glucose or as tumour xenografts. Remarkably, the biguanide sensitivity of cancer cells with mtDNA mutations was reversed by ectopic expression of yeast NDI1, a ubiquinone oxidoreductase that allows bypass of Complex I function5. Thus, we conclude that mtDNA mutations and impaired glucose utilization are potential biomarkers for identifying tumours with increased sensitivity to OXPHOS inhibitors