Cubic interpolation based channel estimator for rectangular M-QAM

This paper propose a Pilot Symbol Assisted Modulation (PSAM) channel estimation and compensation technique for rectangular M-QAM based on Cubic interpolation in order to determine the channel state information (CSI) over flat Rayleigh fading channels. The proposed Cubic channel estimator technique is based on sliding window approach and pilot symbol estimates adjustment in order to reduce its computational time complexity. The Cubic estimator is combined with the Koetter and Vardy (KV) Reed-Solomon (RS) decoder to test its performance. The simulation results show that the Cubic interpolation gives the same performance as the Linear, and Sinc interpolators over slow flat Rayleigh fading channel; however, it achieves significant performance improvement of +1.0dB in symbol error rate (SER) over fast flat Rayleigh fading channel.Keywords: CSI, cubic estimator, fading channel, M-QAM, PSA

Solar quiet variation of the horizontal and vertical components of geomagnetic field using wavelet analysis.

The solar quiet variations of horizontal and vertical (SqH and SqZ) components of the geomagnetic field obtained from both the Northern Hemisphere and Southern Hemisphere of the International Real-Time Magnetic Observatory Network (INTERMAGNET) during solar maximum years of 2001 were investigated. The results show enlargement of SqH component of the geomagnetic field during the daytime, attributed to equatorial electrojet current closer to the geomagnetic equator at the electrojet stations (BNG and MBO) which are produce from large eastward flow of the current. It was observed that the SqZ is positive at the southward and negative at the northward hemispheres. The SqZ is amplified at HER and HBK around the daytime. Wavelet power spectrum (WPS) based approach was employed to analyse the SqH, SqZ, and rate of induction (SqZ/SqH) time series in a sequence of time scaling from January to December. The higher energy of SqH and SqZ of the wavelet coefficients is noticeable at a high frequency. The monthly variation rate of induction (SqZ/SqH) analyses during the solar quiet (Sq) variations are associated to the influence of equatorwards penetration of electric fields from the field-aligned current, Earth conductivities, the effect of the ocean and ionospheric conductivities.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

The ethanol leaf extract of Moringa oleifera leaf extract blunts isoproterenol-induced cardiotoxicity in rats through mitigation of free radical production and down regulation of cardiac troponin and nuclear factor kappa B

Heart disease including coronary artery disease, ischemic heart disease and myocardial infarction is a leading cause of death in the world. Moringa oleifera is a popular plant in folkloric medicine. This study evaluated the effect of the ethanol leaf extract of Moringa oleifera (ELMO) on isoproterenol-induced myocardial infarction in rats. Thirty five male Wistar rats were randomly divided into 5 groups of 7 animals per group i.e. Group A (control), Group B (Toxicant), Groups C and D animals were given 50 mg/kg and 100 mg/ kg of (ELMO), respectively for 7 days and on day 8 were given 100mg/kg of isoproterenol. Group E animals received 100 mg/kg of ELMO only for 7 days. Serum analysis of CK- MB, Myeloperoxidase, Nitric oxide and Total protein, heart harvested for biochemical assays for the analysis of Advanced oxidative protein product (AOPP), Protein carbonyl (PC), Malonaldehyde (MDA), Superoxide dismutase (SOD), Glutathione transferase (GST), Reduced glutathione (GSH), Glutathione peroxidase (GPx), Total thiol, Non-protein thiol and Hydrogen peroxide generation), histology and immunohistochemistry (CTnI, NF-KB) were carried out. There was significant (p < 0.05) reduction in SOD, GPx, GST, increased myeloperoxidase, Protein carbonyl, AOPP, MDA levels and H2O2 generation in toxicant groups but there was corresponding increase in the antioxidant enzymes and decrease in markers of oxidative stress and inflammation in ELMO treated groups. The toxicant also caused severe histopathological changes in the heart tissues and these were corrected by all the doses of the extract. There was increase expression of CTnI and NF-KB in the toxicant group but down regulation of these proteins by the extract. The results showed that Moringa oleifera possess cardiac protective effect