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The amount of sand moving parallel to a coastline forms a prerequisite for many harbor design projects. Such information is currently obtained through various empirical formulae. Despite so many works in the past, an accurate and reliable estimation of the rate of sand drift has still remained a problem. It is a non-linear process and can be described by chaotic time-series. The current study addresses this issue through the use of Adaptive Neuro-Fuzzy Inference System (ANFIS). ANFIS is about taking an initial fuzzy inference system (FIS) and tuning it with a back propagation algorithm based on the collection of input-output data. ANFIS was developed to predict the sand drift from a variety of causative variables. The structure and algorithm of ANFIS for predicting the rate of sand drift is described. The Adaptive Neuro-Fuzzy Inference System was validated by confi rming its consistency with a database of specifi ed physical process.
For validation purposes, characteristic parameters for quantitative detection were estimated according to the PN-EN ISO 16140. Additionally, a comparison between validated real-time PCR method and traditional methods based on the isolation of this pathogen on differential agar media was conducted. The validated method has shown the possibility of detection of 58 copies of ntnh gene (genome equivalents) for DNA obtained from dilution of pure Clostridium botulinum NCTC 887 cells. For DNA obtained from the contaminated food and feed samples inhibitory effect was observed. The tested method has shown high specificity proved by the examination of DNA obtained from C. botulinum reference strains and other strains of Clostridium sp. The specificity has also proved the obtained concordance between results from analyses using test on laboratory mice with those from analyses using the tested real-time PCR method. The obtained results have shown that the described method gives the possibility to detect the pathogen without isolation and to shorten time of analysis in comparison to the traditional methods, based on isolation of this pathogen on differential agar media.
The research methodology recommended by the OECD (Organization of Economic Co-operation and Development) and ISO (International Organization for Standardization) guidelines for testing of chemicals meets the most criteria expected for ecotoxicological testing except the testing condition and the organic matter. The guidelines were initially developed by temperate countries, with testing conditions as 20 °C and the organic matter as sphagnum peat which is commonly available in those countries. But these two criterions are difficult to be followed in tropical countries. Thus there arises a need of modifying these criterions for toxicity studied in tropical regions. In this study a trial was made for substituting the fermented coir pith for sphagnum peat and the validation of the modified tropical artificial soil (TAS) was done by conducting chronic toxicity studies on Eisenia fetida against an inorganic fertilizer, superphosphate (SP) under tropical condition, i.e., 28 ±2 °C. The performed study showed that the SP determined lower earthworm mortality in TAS comparing to OECD soil for all tested concentration levels. The number of juveniles produced in OECD soil was also significantly reduced (p < 0.05) than in TAS. This may be due to the production of large amount of hydrogen ions when the temperature increases and making the medium acidic. The fermented coir pith was more suitable for ecotoxicity studies under tropical condition than sphagnum peat.
Our paper presents a model of the water-pipe network for the Kawie Góry supply zone. The zone under analysis is part of the network operated by the PWiK (Water-Pipe and Sewage Company) in Czestochowa. The model was made in the Epanet program using numerical and operational data. The water-pipe network under examination supplies water to a family housing estate and is fed from a field water-supply reservoir. The total population of the area is approx. 1,500 people, the length of the waterpipe network is 11,704 running meters, and the pipe diameter range is 100-150 mm. The pipes are made of grey cast-iron, PE, and PVC. Based on the selected measurement points, calibration of the model was performed. Within the validation of the model, sensitivity analysis was made. Then, a series of simulations were performed to illustrate the network operation for variable water supply and demand conditions. Multi-period analysis was employed for modeling. The developed model made it possible to determine the magnitude of pressure in the network points, and flows in particular sections for operational parameters under consideration. The prepared model can also provide a base for alternative network management variants, for example in the case of failure or increased water demand and enable the forecasting of possible water shortage locations. In the event of the development of the network, in turn, it will enable the optimal design of new lines.
The aim of this study was to determine which method of hygienic behaviour assessment is more reliable: the evaluation of the pierced brood removal rate or the evaluation of the freeze-killed brood removal rate. Additionally, we aimed to determine whether freeze-killed brood should be placed in colonies when defrosted or still frozen. Defrosted freeze-killed brood was removed faster within a 24 h period. The removal rates for pierced brood and frozen freeze-killed brood were similar in hygienic colonies. In non-hygienic colonies, pierced brood was removed at a significantly slower rate than frozen or defrosted freeze-killed brood. The mechanisms of removing frozen and defrosted freeze-killed brood were similar to each other and different from those observed in the case of pierced brood. The defrosting of brood prior to its introduction into colonies seems inadvisable, as it accelerates brood removal. Our results confirm the hypotheses of those researchers who believe that the frozen freeze-killed brood removal test is not always appropriate. A good solution is, therefore, to perform the frozen freeze-killed brood and pin-killed brood removal tests simultaneously. The time from the beginning of the tests to the moment 50% and 75% of dead-brood cells have been cleaned up should be assumed as the appropriate duration of the hygienic behavior evaluation tests.
To develop a new animal model for gallbladder ultrasonography 16 adult sheep of both sexes were used. Ultrasonographic examinations were performed in fed or fasted sheep every 30 min for 3-5 h. Every gallbladder was visualized, then its maximal length, height and width were measured. Afterwards, the gallbladder volume was calculated with three methods. The maximal and minimal values of gallbladder volume in both fed and fasted animals differed significantly (p < 0.05) indicating the existence of gallbladder contractions detectable in both states examined. The results of gallbladder volumes calculated with various methods were also significantly different. The values obtained from the method describing the gallbladder as a cone were about 50% lower than that obtained from two ellipsoid methods. The validation study showed that the true value remained somewhere between the values obtained indirectly. This warrants further investigation, however.
Recent clinical research has pointed at hyperhomocysteinemia as an independent risk factor in a number of cardiovascular and neurological diseases. We have improved a chromatographic method of total plasma homocysteine measurements in order to obtain higher sensitivity, reliability and reproducibility. The method demonstrates excellent linearity (R = 0.999), range (< 2-100 µM), precision (instrumental RSD 0.06 and method RSD 1.17), accuracy (recovery of 99.92 and RSD 1.27), reproducibility, quantification limit and ruggedness (e.g. pH from 2.0 to 2.5). Because even a small increase in homocysteine level can be a significant risk factor of cardiovascular diseases, such a precise method is required. The constructed method allows the measurement of plasma pyridoxal phosphate, PLP, the co-enzyme form of vitamin B6, on the same column and similar reagents. The developed method has been successfully applied to measure both total plasma and serum homocysteine in a group of acute stroke patients.
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