The Impact of User Effects on the Performance of Dual Receive Antenna Diversity Systems in Flat Rayleigh Fading Channels

In this paper we study the impact of user effects on the performance of receive antenna diversity systems in flat Rayleigh fading channels. Three diversity combining techniques are compared: maximal ratio combining (MRC), equal gain combining (EGC), and selection combining (SC). User effects are considered in two scenarios: 1) body loss (the reduction of effective antenna gain due to user effects) on a single antenna, and 2) equal body loss on both antennas. The system performance is assessed in terms of mean SNR, link reliability, bit error rate of BPSK, diversity order and ergodic capacity. Our results show that body loss on a single antenna has limited (bounded) impact on system performance. In comparison, body loss on both antennas has unlimited (unbounded) impact and can severely degrade system performance. Our results also show that with increasing body loss on a single antenna the performance of EGC drops faster than that of MRC and SC. When body loss on a single antenna is larger than a certain level, EGC is not a “sub-optimal” method anymore and has worse performance than SC

Comparative study of the phenolic composition of seeds from grapes cv cardinal and alphonse lavallee during last month of ripening

During the last month of ripening, the phenolic composition of seeds from two widely distributed table grapes, cv Cardinal and Alphonse Lavallee, was determined by HPLC/DAD/ESI/MS. Besides, the concentrations of nutrients in leaf blades of grapevine were measured. Generally, the most abundant phenolic in grape seed was gallic acid, followed by methyl gallate and monomeric flavan-3-ols. In comparison to Alphonse Lavallee, the amounts of phenolics were higher in grape seed of Cardinal, in which gallic acid glucoside was not detected. Among analyzed phenolics, the increase of gallic acid was evidenced in grape seed of Cardinal. The most of phenolics decreased during the last month of grape ripening, and some of them had no significantly different content. Results of bivariate correlations showed that the amounts of some phenolics in grape seed of Cardinal increased with increasing of the content of potassium and phosphorus in leaves

Validación y reproducibilidad de un cuestionario de frecuencia de consumo alimentario para valorar la ingesta de lípidos y fitoquímicos.

Background: epidemiological studies have been related food intake with the incidence of nontransmissible chronic diseases. Objective: the purpose of the present study was to analyze the validity and reproducibility of a food frequency questionnaire (FFQ) aimed at assessing lipid and phytochemical intake. Material and Methods: FFQ was administered to 45 people of both sexes, aged between 20 and 72 years old and resident in Cordoba, Argentina. The FFQ included 257 questions referring to foods, their consumption frequency and portion size. Regarding consumption of fruit and vegetables, the season was also taken into account. The questionnaire was applied at two different periods (FFQ1 and FFQ2) with a break of six months in between. As a reference, the 24-hour dietary recall was used (24HDR) three times. The mid intake of FFQ1-FFQ2, the 24HDR-FFQ2 median intake, median difference, Mean Absolute Deviation from the median differences (MAD), Wilcoxon signed rank sum test and Spearman rank order correlation coefficients were calculated to analyze the accuracy of the FFQ data. Results: the correlation coefficients for FFQ1-FFQ2 varied from 0.52 for 20:5 n3 eicosapentanoic (EPA) fatty acid to 0.89 for 4:0 butyric fatty acid (p<0.05). For 24HDR-FFQ2, the values ranged from 0.19 for lycopene to 0.93 for EPA fatty acid (p<0.05). Conclusion: the analysis carried out showed an acceptable validity and reproducibility of the FFQ, thus enabling it to be used in research relating the intake of lipids and phytochemicals and the risk of non-transmissible diseases.publishedVersio

Hemijske karakteristike visoko-krečnjačkih zemljišta koje određuju raspodelu fosfora

Phosphorus fractions from three highly calcareous soils (average, 24.9 +/- 4.8 %CO32-) from sampling sites with a Mediterranean climate were isolated by sequential extraction. In order to provide a more reliable basis for the definition of the obtained P-fractions, principal component analysis was applied and from the chemical characteristics of the 14 investigated soils, those characteristics which define at he content and association features of the P-fractions were assessed. The soils are characterized by a relatively high pH (8.0-8.2) and by significantly differing contents of organic mater, acid-soluble Mg and total P. These differences affected the various association features of the P-fraction with the soil constituents. The NH4F-P fraction (isolated with 0.5 M NH4F, pH 8.2) is defined by the contents of the main metals of the oxide-hydroxide-clay associations (Al, Fe, Mn) or by the the redox potential (Eh) of Mn. The accumulation of NaOH-phosphorus (extractable with 0.1 M NaOH) depended on the constituents of the oxide hydroxide-clay association, the humic substances and Eh-related factors. In those soils in which NaOH-P is defined by the oxide-hydroxide-clay association, the participation of Fe as a bridge-forming metal is proposed. The main part of total P, i.e., Delta P = TP - (NH4F-P + NaOH-P) is defined by the status of Mn- and Fe-humic complexes or by the concentration of hydroxyl-ions.Iz tri visoko-krečnjačka zemljišta (prosečni sadržaj CO 3 2- 24.9 ± 4.8%, pH 8.0 - 8.2), sa lokacija sa sredozemnom klimom, izolovane su frakcije fosfora sekvencijalnom ekstrakcijom. U cilju obezbeđivanja pouzdanije osnove za definisanje dobijenih frakcijafosfora (P-frakcija), primenjena je analiza principalne komponente (PC-analiza). Među 14 hemijskih karakteristika zemljišta, izdvojene su one koje definišu sadržaj pojedinih P-frakcija i prirodu njihove asocijacije sa sastojcima zemljišta. Frakcija NH 4-P (izolovana sa 0,5M NH 4F, pH = 8,2) definisana je sadržajem glavnih metala oksidne-hidroksidne-glinene asocijacije (Al, Fe, Mn) ili Eh-statusom izraženim sadržajem Mn. Akumulacija NaOH-P (ekstrahovanog sa 0,1 M NaOH) zavisila je od sastojaka oksidne-hidroksidne-glinene asocijacije, od huminskih supstanci i od faktora koji stoje u vezi sa Eh. U onim zemljištima u kojima je NaOH-P definisana sastojcima oksidne-hidroksidne-glinene asocijacije, pretpostavljeno je vezivanje fosfora preko Fe-mostova. Glavna količina fosfora ∆P = TP - (NH 4F-P + NaOH-P), u pojedinim zemljištima definisana je ili statusom Mn- i Fe-huminskih kompleksa, ili pH-vrednošću

Time-dependent reduction of structural complexity of the buccal epithelial cell nuclei after treatment with silver nanoparticles

Recent studies have suggested that silver nanoparticles (AgNPs) may affect cell DNA structure in in vitro conditions. In this paper, we present the results indicating that AgNPs change nuclear complexity properties in isolated human epithelial buccal cells in a time-dependent manner. Epithelial buccal cells were plated in special tissue culture chamber / slides and were kept at 37°C in an RPMI 1640 cell culture medium supplemented with L-glutamine. The cells were treated with colloidal silver nanoparticles suspended in RPMI 1640 medium at the concentration 15 mg L−1. Digital micrographs of the cell nuclei in a sample of 30 cells were created at five different time steps: before the treatment (controls), immediately after the treatment, as well as 15 , 30 and 60 min after the treatment with AgNPs. For each nuclear structure, values of fractal dimension, lacunarity, circularity, as well as parameters of grey level co-occurrence matrix (GLCM) texture, were determined. The results indicate time-dependent reduction of structural complexity in the cell nuclei after the contact with AgNPs. These findings further suggest that AgNPs, at concentrations present in today's over-the-counter drug products, might have significant effects on the cell genetic material