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Romvári R Szabó A Andrássy G Petrási Z Donkó T Horn P 《Acta veterinaria Hungarica》2008,56(3):313-322
A two-way selection procedure was performed on a Landrace pig line. First the cardiac output (CO) values (6.89 +/- 1.27 L/min) were estimated by ECG-gated magnetic resonance imaging (MRI) to quantify the heart performance of the boars (n = 30), then total body skeletal muscle volume (MVTB; 48.7 +/- 5.17 dm3) was determined applying spiral computerised tomography (CT). The relative cardiac output value (RCO) was developed, expressing the relationship between CO and MVTB. Four superior [RCO value below 6.7 dm3 / (L x min(-1))] and one minus variant [(8.97 dm3 / (L x min(-1))] boars were taken into breeding. The best fifteen percentage of the first generation males (n = 30) was characterised according to their RCO values. Significant difference was found between the developed performance measure of the progenies of minus and plus variant boars [8.2 +/- 0.65 and 5.63 +/- 0.70 dm3 / (L x min(-1)), n = 7 and 23], respectively. Comparing the existing five progeny groups, all of the 'HP+' groups differed significantly from the 'HP-' one, where the largest heart performance contrast found was 3.2 dm3 / (L x min(-1)). Based upon the results, the selection is being continued on a larger population. 相似文献
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To study the genetic characteristics of DT104 strains of Salmonella Typhimurium and the prevalence of Salmonella Genomic Island (SGI1) in Hungary, 140 recent Salmonella strains of food and animal origin were examined. For the first time in Hungary, the SGI1 was found in 17 out of 59 S. Typhimurium isolates (all proven to be DT104 phage type). These 17 strains were then subtyped by pulsed-field gel electrophoresis (PFGE) into 6 pulsotypes which were less correlated with the geographic origin than with the animal species of origin. 相似文献
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Rosenfeld DE Gengeliczki Z Smith BJ Stack TD Fayer MD 《Science (New York, N.Y.)》2011,334(6056):634-639
Ultrafast two-dimensional infrared (2D IR) vibrational echo spectroscopy has proven broadly useful for studying molecular dynamics in solutions. Here, we extend the technique to probing the interfacial dynamics and structure of a silica surface-tethered transition metal carbonyl complex--tricarbonyl (1,10-phenanthroline)rhenium chloride--of interest as a photoreduction catalyst. We interpret the data using a theoretical framework devised to separate the roles of structural evolution and excitation transfer in inducing spectral diffusion. The structural dynamics, as reported on by a carbonyl stretch vibration of the surface-bound complex, have a characteristic time of ~150 picoseconds in the absence of solvent, decrease in duration by a factor of three upon addition of chloroform, and decrease another order of magnitude for the bulk solution. Conversely, solvent-complex interactions increase the lifetime of the probed vibration by 160% when solvent is applied to the monolayer. 相似文献
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Füzfai Z Katona ZF Kovács E Molnár-Perl I 《Journal of agricultural and food chemistry》2004,52(25):7444-7452
Our gas chromatography-mass spectrometry method--developed for the simultaneous quantitation of mono-, di-, and trisaccharides, sugar alcohols, caboxylic and amino acids, measured as their trimethylsilyl-(oxime) ether/ester derivatives, from one solution by a single injection, prepared in the presence of the fruit matrix--has been extended/utilized for special purposes. The compositions of (i) freshly harvested and stored sour cherries (Prunus cerasus), (ii) apples obtained from organic and integrated productions (Malus domestica), and (iii) green and ripe bers (Zizyphus mauritiana L.) were compared. On the basis of earlier, basic researches (derivatization, quantitation, and fragmentation studies of authentic compounds), we demonstrate the reproducible quantitation of the main and minor constituents in a wide concentration range (approximately 1 x 10(-)(3) to >/=40%, in total up to < or =98%, calculated on dry matter basis of the fruit matrices). Reproducibility of quantitations, calculated on the basis of their total ion current values, provided an average reproducibility of 3.3 (sour cherries), 6.2 (apple), and 4.3 (ber) RSD %, respectively. 相似文献
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Confidence limits for prevalence of disease adjusted for estimated sensitivity and specificity 总被引：1，自引：0，他引：1
Prevalence of a disease is usually assessed by diagnostic tests that may produce false results. Rogan and Gladen (1978) described a method to estimate the true prevalence correcting for sensitivity and specificity of the diagnostic procedure, and Reiczigel et al. (2010) provided exact confidence intervals for the true prevalence assuming sensitivity and specificity were known. In this paper we propose a new method to construct approximate confidence intervals for the true prevalence when sensitivity and specificity are estimated from independent samples. To improve coverage we applied an adjustment similar to that described in Agresti and Coull (1998). According to an extensive simulation study the new confidence intervals maintain the nominal level fairly well even for sample sizes as small as 30; minimum coverage is above 88%, 93%, and 98% at nominal 90%, 95%, and 99%, respectively. We illustrate the advantages of the proposed method with real-life applications. 相似文献
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Xudong Xie Stefan Norra Zsolt Berner Doris Stüben 《Water, air, and soil pollution》2005,167(1-4):39-57
The present study was carried out to analyse and identify relationships among stream water chemistry, land use, and geology in Baden-Württemberg, a federal state in the south-west of Germany. The investigation is based on data from 88 monitoring stations, which cover almost the whole area of Baden-Württemberg. The database on water chemistry includes 21 parameters such as major cations, anions, heavy metals, dissolved organic carbon, pH, acid neutralization capacity, and conductivity. The study area is classified into 16 different land use categories and 12 types of geological formations. Using multivariate statistical methods (factor analysis), the relationships among different parameters were revealed by identifying ten uncorrelated factors. The data analysis indicates a complex interaction among stream water chemistry, lithologic composition of the geological formations, and land use type, with an intricate fingerprintings of the different parameters. The most important factors in terms of the represented variance are the main mineralization of the stream water (due to interaction with the geological underground) and anthropogenic nutrients introduced by different agricultural activities. Based on the results of factor analysis (factor score), the stream water chemistry is regionalized using a Geographic Information System (ArcView). 相似文献