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11.
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   
12.
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   
13.
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   
14.
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   
15.
In our study, a traditionally used (Grayling, already used in cyprinid species) and a newly tested (Pike) extender was tested to avoid sperm agglutination phenomenon following thawing during carp sperm cryopreservation. A large‐scale (elevated volume of sperm) freezing method in a controlled‐rate freezer using 5 ml straw and 10 ml cryotube was also systematically established. In all experiments, the sperm cryopreserved in using Grayling extender (except only one sample) showed an agglutination phenomenon (damaged and intact cells adhered to each other) after thawing where Pike extender resulted the regular cell suspension. No significant difference was observed between the two cryopreserved groups (Pike and Grayling extender) in all motility parameters using the 0.5 ml straw and the polystyrene box. Similarly, motility parameters did not show a significant difference in the two frozen groups with the 5 ml straw, also in the polystyrene box. A significantly higher progressive motility (pMOT, Grayling: 54% ± 8%, Pike: 37% ± 5%), straight line velocity (VSL, Grayling: 50 ± 5 µm/s, Pike: 39 ± 4 µm/s) and beat cross frequency (BCF, Grayling: 20 ± 1 Hz, Pike: 17 ± 1 Hz) was observed in the case of the grayling extender by the 5 ml straw cryopreserved in a controlled‐rate freezer (CRF) compare to the pike extender. A significantly higher VSL (Grayling: 45 ± 3 µm/s, Pike: 38 ± 4 µm/s) was observed by the grayling extender using the 10 ml cryotube than with the pike extender. Despite the randomly occurring differences in a few parameters, our new controlled freezing method using the newly tested Pike extender, the 5 ml straw or the 10 ml cryotube can be a good solution for the preservation of elevated volume of carp sperm.  相似文献   
16.
17.
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   
18.
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   
19.
The effect of heavy metals on the motility parameters of common carp sperm was investigated. In vitro test systems are widespread in ecotoxicology, and fish sperm can be a suitable model. For this reason, studies had been carried out in this topic; however, the published methods are not standard in several aspects (donor species, measured endpoint, etc.). In this study, a previously published toxicology-aimed sperm analysis protocol was tested to examine the effect of heavy metals (arsenic, cadmium, chromium, copper, mercury, nickel, zinc,) on common carp sperm. According to our results, PMOT is the most sensitive of the investigated parameters: dose-response was observed in case of each metal at low concentrations, already after 30 min of exposure. VCL was less sensitive: lower effects were observed at the same concentrations compared to PMOT. Among the examined parameters, LIN was the least affected: a dose-response was observed only in case of arsenic and mercury. The same sensitivity of motility parameters was observed on zebrafish sperm previously. Moreover, we found that PMOT, VCL, and LIN of common carp sperm were affected at the same concentrations as it had been observed in zebrafish, when the identical analytical protocol was applied. The only exception was As3+, where common carp sperm proved to be more sensitive: lower concentrations already reduced its motility parameters. Consequently, PMOT of common carp sperm is an accurate and fast bioindicator of aquatic pollution.  相似文献   
20.
In Hungary, black locust (Robinia pseudoacacia L.) is one of the most important exotic species, forming entire stands. Its importance is increasing in many other countries. As a result of a new selection program eight black locust clones have been improved for establishing clone trials and a seed orchard. In this study juvenile growth and stem quality of micropropagated clones of black locust were evaluated on a marginal site in central Hungary. At ten years old, the clones ’MB17D3/4’ and ’PV201E2/4’ appeared to be especially promising for high quality wood production under arid hydrological conditions. A tissue culture method can be considered a suitable tool of propagating superior individual trees and offers new prospects for the rapid cloning of selected genotypes.  相似文献   
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