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Number of results: 56
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Abstract

To find out what affected sea level fluctuations in the past, researchers have to turn to the mountains. In ancient geological epochs, today’s Alps and Tatras were actually once on the ocean floor.
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Abstract

This paper deals with the problem of nonstationarity of regressors in binary choice model. The limit distribution of the ML-estimator is mixed normal, but restriction testing shall not be based on standard t-statistic. The results of the conducted Monte Carlo experiment demonstrate that the true size of the restriction test is far from the significance level. Therefore, the t-Student statistic should be modified and this paper proposes its modification. The results of the Monte Carlo investigation point to the superiority of the new statistic.
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Abstract

In many research studies it is argued that it is possible to extract useful information about future real economic activity from the performance of financial markets. However, this study goes further and shows that it is not only possible to use expectations derived from financial markets to forecast future economic activity, but that data about the financial system can be used for this purpose as well. This paper sheds light on the ability to forecast real economic activity, based on additional and different financial variables than what have been presented so far. The research is conducted for the Polish emerging economy on the basis of monthly data. The results suggest that, based purely on the data from the financial system, it is possible to construct reasonable measures that can, even for an emerging economy, effectively forecast future real economic activity. The outcomes are proved by two different econometric methods, namely, by a time series analysis and by a probit model. All presented models are tested in-sample and out-of-sample.
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Abstract

This article deals with the presentation of St. Hyacinth (before 1200-1257) placed on the back seats of the stalls of the monastery churches in Poznań and Klimontów. The first known presentations of St. Hyacinth can be dated back to the fifteenth century, but certainly the canonisation of this Dominican friar (1594) gave a new impulse to creating artistic presentations and cycles. An important role in making his name more popular among Catholics was played by the graphics, which produced examples to be followed in other forms. Among the first graphics was the engraving of Raffaelo Guidi, made in 1594-1595 in Rome according to the drawing of Antonio Tempesta. One can presume that the copy of a late gothic painting from the Dominican church in Cracow served as an inspiration to produce the main scene of this print. A less elaborate engraving, taking into consideration the number of scenes depicted, was the one of Camillo Graffico, produced in Rome at this same time. In 1600 Jan Sadeler followed the concept of Guidi when he published his print in Venice. In 1601 Giacomo Lauro published in Rome a print presenting 12 scenes on the edge. This artefact inspired the Cologne publisher Peter Overadt, who printed in 1605 his engraving together with others, known as the cycle Icones et Miracula Sanctorum Poloniae. He significantly influenced Polish art in the seventeenth century. The low relief placed on the back-seats of the Poznań stalls, dating back to ca. 1620-1630, used the print of Overadt as a source for seven episodes (out of fourteen preserved). The back-seats at the church in Klimontów, produced ca. 1620-1640, include 10 scenes (out of 11) based on Overadt’s graphics. Both of these cycles were based on these same sources and were made separately, using other motifs, not always fully discovered, and indirectly some literary works were dedicated to St. Hyacinth.
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Abstract

The present studies explore how activating concepts pertaining to the origins of interindividual differences affect the processing of stereotypical and counterstereotypical information. The concepts, i.e., nature and nurture, are both assumed to evoke similar stereotypical expectations although nurture implies greater flexibility. The studies show that stereotypical information enhances whereas counterstereotypical information diminishes stereotyping when nurture is activated. In contrast, counterstereotypical evidence challenges what activated nature would suggest and perceivers primed with nature evince stronger stereotyping when they encounter counterstereotypical information. The results also show that priming nature leads perceivers to attribute stereotype conformity to internal causes whereas nurture accredits conformity to situational constraints. Stereotype flexibility is associated with the subjective ease with which perceivers can both imagine counterstereotypical and mentally undo stereotypical evidence.
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Abstract

Żeby dowiedzieć się, co w przeszłości wpływało na wahania poziomu mórz, trzeba pojechać w góry – Alpy albo Tatry. One bowiem w dawnych epokach geologicznych były dnem oceanu.
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Abstract

The aim of this study was to determine to what extent the ions present in hard water (125 mg/L of MgCl2 and 500 mg/L of CaCl2) may intensify the feed-induced decrease in oxytetracycline (OTC) absorption rate in broiler chickens after single oral administration at a dose of 15 mg/kg. Drug concentrations in plasma were determined by liquid chromatography-tandem mass spectrometry and combined, compartmental and non-compartmental approach was used to assess OTC pharmacokinetics. The administration of feed decreased the absolute bioavailability (F) of OTC from 12.70%±4.01 to 6.40%±1.08, and this effect was more pronounced after the combined administration of OTC with feed and hard water (5.31%±0.90). A decrease in the area under the concentration- time curve (AUC0-t), (from 10.18±3.24 μg·h/ml in control to 5.13 μg·h/ml±1.26 for feed and 4.26 μg·h/ml±1.10 for feed and hard water) and the maximum plasma concentration of OTC (Cmax) (from 1.22±0.18 μg/ml in control, to 1.01 μg/ml ±0.10 for hard water, 0.68 μg/ml±0.10 for feed and 0.61 μg/ml±0.10 for feed and hard water) was observed. The results of this study indicate that feed strongly decreases F, AUC0-t and Cmax of orally administered OTC. The ions present in hard water increase this inhibitory effect, which suggests that, therapy with OTC may require taking into account local water quality and dose modification, particularly when dealing with outbreaks caused by less sensitive microorganisms.
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Abstract

Two low-cost methods of estimating the road surface condition are presented in the paper, the first one based on the use of accelerometers and the other on the analysis of images acquired from cameras installed in a vehicle. In the first method, miniature positioning and accelerometer sensors are used for evaluation of the road surface roughness. The device designed for installation in vehicles is composed of a GPS receiver and a multi-axis accelerometer. The measurement data were collected from recorded ride sessions taken place on diversified road surface roughness conditions and at varied vehicle speeds on each of examined road sections. The data were gathered for various vehicle body types and afterwards successful attempts were made in constructing the road surface classification employing the created algorithm. In turn, in the video method, a set of algorithms processing images from a depth camera and RGB cameras were created. A representative sample of the material to be analysed was obtained and a neural network model for classification of road defects was trained. The research has shown high effectiveness of applying the digital image processing to rejection of images of undamaged surface, exceeding 80%. Average effectiveness of identification of road defects amounted to 70%. The paper presents the methods of collecting and processing the data related to surface damage as well as the results of analyses and conclusions.
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Abstract

Paper present a thermal analysis of laser heating and remelting of EN AC-48000 (EN AC-AlSi12CuNiMg) cast alloy used mainly for casting pistons of internal combustion engines. Laser optics were arranged such that the impingement spot size on the material was a circular with beam radius rb changes from 7 to 1500 m. The laser surface remelting was performed under argon flow. The resulting temperature distribution, cooling rate distribution, temperature gradients and the depth of remelting are related to the laser power density and scanning velocity. The formation of microstructure during solidification after laser surface remelting of tested alloy was explained. Laser treatment of alloy tests were perform by changing the three parameters: the power of the laser beam, radius and crystallization rate. The laser surface remelting needs the selection such selection of the parameters, which leads to a significant disintegration of the structure. This method is able to increase surface hardness, for example in layered castings used for pistons in automotive engines.
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Abstract

The aim of the research was an examination of potential impact of milk yield on the intercompartmental clearance – distribution clearance as well as determination of the variability of obtained pharmacokinetic parameters by the population approach using a two-compartmental structural model. Blood perfusion has a considerable impact on physiology of the udder and kinetics of drugs that are distributed in this organ. The research was performed on healthy Holstein- Friesian and Polish Black-White cows at the age of 4-10 years. Determination of antibiotics (ampicillin, amoxicillin, cefoperazone, penicillin G prokaine, cloxacillin, cefacetril) concentration was carried out after their every intramammary administration to one quarter of the udder. A population pharmacokinetic model was created to fit milk concentration data. General milk yield of a single cow was used as a variable. A population analysis was conducted using non-linear mixed-effect modeling. The impact of milk productivity was set solely by reference to intercompartmental clearance only in case of penicillin G, cloxacillin and ampicillin. It, has been found that milk yield, depending on a drug, influenced the distribution clearance of the drug to varying degrees. It means indirectly that increased perfusion of the udder has a different impact on drug distribution from the udder to the bloodstream.
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Abstract

The paper includes a summary of long-time research conducted by a research team in the Institute of Electrical Engineering and Computer Science at Silesian University of Technology. The research work has principally been related to selected problems in the field of analysis and synthesis of systems aimed at symmetrisation and improvement of some power quality parameters. This paper constitutes the second part of the report on the research. It has been devoted to three-phase system symmetrisation as well as effective elimination of higher harmonics and substantial improvement of power quality by means of hybrid active power filters.
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Abstract

The paper includes a summary and a background of long-time research conducted by a research team in the Institute of Electrical Engineering and Computer Science at SilesianUniversity of Technology. The researchwork has principally been related to selected problems in the field of analysis and synthesis of systems aimed at symmetrisation and improvement of some power quality parameters. This paper constitutes a first part of the report on the research. It has been devoted to effective elimination of higher harmonics and reactive power compensation by means of parallel active power filters. The other problem discussed in this paper is related to this issue and it is very important from the economic point of view; it addresses optimal sizing and placement of active power filters in investigated power networks.
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