In this paper we demonstrate that fuzzy logic can provide a better tool for predicting recycling behaviour than the customarily used linear regression. To show this, we take a set of empirical data on recycling behaviour (N=664), which we randomly divide into two halves. The first half is used to estimate a linear regression model of recycling behaviour, and to develop a fuzzy logic model of recycling behaviour. As the first comparison, the fit of both models to the data included in estimation of the models (N=332) is evaluated. As the second comparison, predictive accuracy of both models for "new" cases (hold-out data not included in building the models, N=332) is assessed. In both cases, the fuzzy logic model significantly outperforms the regression model in terms of fit. To conclude, when accurate predictions of recycling and possibly other environmental behaviours are needed, fuzzy logic modelling seems to be a promising technique.

• Klíčová slova
• Empirical test, Fuzzy logic, Prediction, Recycling behaviour,
• MeSH
• fuzzy logika * MeSH
• lidé MeSH
• lineární modely * MeSH
• recyklace * statistika a číselné údaje   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

A tutorial and spreadsheet for the validation and bottom-up uncertainty evaluation of quantifications performed by instrumental methods of analysis based on linear weighted calibrations is presented. The developed tool automatically assesses if calibrator values uncertainty is negligible given instrumental signal precision, assesses signal homoscedasticity by the Levene's test, guides the selection of weighting factors and evaluates the fitness of the regression model to define the calibration curve. The spreadsheet allows the use of the linear weighted regression model without the need for collecting many replicate signals of calibrators and sample by taking previously developed detailed models of signal precision variation in the calibration interval after adjustments to the daily precision conditions. This tool was successfully applied to the determination of the mass concentration of Cd, Pb, As, Hg, Co, V and Ni in a nasal spray by ICP-MS after samples dilution and acidification. The developed uncertainty models were checked through the analysis of nasal sprays after spiking with known analyte concentration levels. The metrological compatibility between estimated and reference analyte levels for 95% or 99% confidence level supports uncertainty model adequacy. The spiked samples were quantified from many replicate signals but uncertainty evaluation from duplicate calibrator and sample signals was assessed by randomly selecting calibrators and sample signals and by numerically defining a minimum acceptable success rate of the compatibility tests. The developed model was proven adequate to quantify the uncertainty of the studied measurements.

• Klíčová slova
• Cross-validation, Elemental impurities, ICP-MS, Uncertainty, Weighted calibration,
• MeSH
• kalibrace MeSH
• lineární modely MeSH
• nejistota MeSH
• nosní spreje * MeSH
• spektrální analýza MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• nosní spreje * MeSH

Permutation methods are commonly used to test the significance of regressors of interest in general linear models (GLMs) for functional (image) data sets, in particular for neuroimaging applications as they rely on mild assumptions. Permutation inference for GLMs typically consists of three parts: choosing a relevant test statistic, computing pointwise permutation tests, and applying a multiple testing correction. We propose new multiple testing methods as an alternative to the commonly used maximum value of test statistics across the image. The new methods improve power and robustness against inhomogeneity of the test statistic across its domain. The methods rely on sorting the permuted functional test statistics based on pointwise rank measures; still, they can be implemented even for large data. The performance of the methods is demonstrated through a designed simulation experiment and an example of brain imaging data. We developed the R package GET, which can be used for the computation of the proposed procedures.

• Klíčová slova
• function-on-scalar regression, general linear model, global envelope test, graphical method, multiple testing correction,
• MeSH
• lidé MeSH
• lineární modely MeSH
• mozek * diagnostické zobrazování   MeSH
• neurozobrazování * MeSH
• počítačová simulace MeSH
• výzkumný projekt MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

State-of-the-art approaches for the prediction of drug-target interactions (DTI) are based on various techniques, such as matrix factorisation, restricted Boltzmann machines, network-based inference and bipartite local models (BLM). In this paper, we propose the framework of Asymmetric Loss Models (ALM) which is more consistent with the underlying chemical reality compared with conventional regression techniques. Furthermore, we propose to use an asymmetric loss model with BLM to predict drug-target interactions accurately. We evaluate our approach on publicly available real-world drug-target interaction datasets. The results show that our approach outperforms state-of-the-art DTI techniques, including recent versions of BLM.

• MeSH
• cílená molekulární terapie * MeSH
• léčivé přípravky metabolismus   MeSH
• lineární modely MeSH
• výpočetní biologie metody   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• léčivé přípravky MeSH

In an attempt to develop predictive relationships, apparent digestible energy (ADE) content (n = 361) as biological dependent variable and dietary contents of crude protein (CP), lipid, ash and gross energy (GE) as independent variables, obtained in 40 studies with 65 different feed ingredients and evaluated with 26 fish species, were subjected to linear correlation and multiple linear regression analysis. With dietary CP and GE contents identified as significant predictors, only 58% of the variation in ADE content could be explained. No improvement in accuracy of regression equations was gained by classification of values according to either feed ingredient (animal proteins, plant proteins, cereals) or fish species (water type, water temperature, feed habit). An R (2)-value of 0.4570 and mean prediction error (MPE) of 0.2085 between predicted and observed ADE values from eight independent studies (n = 37) illustrated the inability of the derived regression equation to accurately predict ADE contents of feed ingredients. Inclusion of dietary crude fibre and nitrogen-free extract (NFE) contents as independent variables did not improve the accuracy of prediction equations. The inadequacy of the use of linear regression to predict DE content from dietary composition across feed ingredients and fish species with high accuracy is discussed.

• MeSH
• dietní proteiny analýza   MeSH
• druhová specificita MeSH
• energetický metabolismus fyziologie   MeSH
• fyziologie výživy zvířat * MeSH
• krmivo pro zvířata analýza   MeSH
• lineární modely MeSH
• lipidy analýza   MeSH
• nutriční hodnota MeSH
• ryby fyziologie   MeSH
• teplota MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• dietní proteiny MeSH
• lipidy MeSH

The linear theory of electromigration, including the first-order nonlinear approximation, is generalized to systems with any equilibria fast enough to be considered instantaneous in comparison with the timescale of peak movement. For example, this theory is practically applied in the electrokinetic chromatography (EKC) mode of the CZE. The model enables the calculation of positions and shapes of analyte and system peaks without restricting the number of selectors, the complexation stoichiometry, or simultaneous acid-base equilibria. The latest version of our PeakMaster software, PeakMaster 6-Next Generation, implements the theory in a user-friendly way. It is a free and open-source software that performs all calculations and shows the properties of the background electrolyte and the expected electropherogram within a few seconds. In this paper, we mathematically derive the model, discuss its applicability to EKC systems, and introduce the PeakMaster 6 software.

• Klíčová slova
• Capillary zone electrophoresis, Electrokinetic chromatography, Linear theory of electromigration, PeakMaster,
• MeSH
• chemické modely MeSH
• elektroforéza kapilární metody   MeSH
• elektrolyty chemie   MeSH
• ionty chemie   MeSH
• kapilární elektrochromatografie metody   MeSH
• lineární modely MeSH
• software * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• elektrolyty MeSH
• ionty MeSH

We discuss several possible phenomena in electrophoretic systems with complexing agents present in the background electrolyte. In our previous work, we extended the linear theory of electromigration with the first-order nonlinear term, which originally applied to acid-base equilibria only, by generalizing it to any fast chemical equilibria. This extension provides us with a fresh insight into the well-established technique of elecktrokinetic chromatography (EKC). We combine mathematical analysis of the generalized model with its solution by means of the new version of our software PeakMaster 6, and experimental data. We re-examine the fundamental equations by Wren and Rowe and Tiselius in the frame of the generalized linear theory of electromigration. Besides, we show that selector concentration can increase inside the interacting-analyte zone due to its complexation with the analyte, which contradicts the generally accepted idea of a consumption of a portion of the selector inside the zone. Next, we focus our discussion on interacting buffers (i.e., buffer constituents that form a complex with the selector). We demonstrate how such side-interaction of the selector with another buffer constituent can influence measuring analyte-selector interactions. Finally, we describe occurrence and mobilities of system peaks in these EKC systems. We investigate systems with fully charged analytes and neutral cyclodextrins as selectors. Although the theory is not limited in terms of the charge and/or the degree of (de)protonation of any constituent, this setup allows us to find analytical solutions to generalized model under approximate, yet realistic, conditions and to demonstrate all important phenomena that may occur in EKC systems. An occurrence of system peaks in a system with fully charged selector is also investigated.

• Klíčová slova
• Cyclodextrin, Elektrokinetic chromatography, Linear theory of electromigration, PeakMaster, Tiselius’ equation,
• MeSH
• cyklodextriny chemie   MeSH
• elektroforéza kapilární metody   MeSH
• elektroforéza metody   MeSH
• elektrolyty chemie   MeSH
• lineární modely MeSH
• pufry MeSH
• software MeSH
• stereoizomerie MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cyklodextriny MeSH
• elektrolyty MeSH
• pufry MeSH

During the first half of the 20th century, it was commonly assumed that radiation-induced health effects occur only when the dose exceeds a certain threshold. This idea was discarded for stochastic effects when more knowledge was gained about the mechanisms of radiation-induced cancer. Currently, a key tenet of the international system of radiological protection is the linear no-threshold (LNT) model where the risk of radiation-induced cancer is believed to be directly proportional to the dose received, even at dose levels where the effects cannot be proven directly. The validity of the LNT approach has been questioned on the basis of a claim that only conclusions that can be verified experimentally or epidemiologically are scientific and LNT should, thus, be discarded because the system of radiological protection must be based on solid science. The aim of this publication is to demonstrate that the LNT concept can be tested in principle and fulfils the criteria of a scientific hypothesis. The fact that the system of radiological protection is also based on ethics does not render it unscientific either. One of the fundamental ethical concepts underlying the LNT model is the precautionary principle. We explain why it is the best approach, based on science and ethics (as well as practical experience), in situations of prevailing uncertainty.

• Klíčová slova
• Dose limitation, Ethical basis, ICRP, LNT, Low radiation dose, Precautionary principle, Radiological protection, Scientific basis,
• MeSH
• dávka záření MeSH
• hodnocení rizik MeSH
• lidé MeSH
• lineární modely MeSH
• nádory vyvolané zářením prevence a kontrola   MeSH
• radiační ochrana * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Intensive selfmonitoring is an important and cost-demanding part of diabetes treatment. Continuous glucose monitoring (CGM) using transcutaneous sensors offers "real time" information on glycemia. In the present study, we assessed the therapeutic efficacy of CGM on metabolic control using two different statistical methods: linear regression and "survival analysis". OBJECTIVES: (1) to assess the therapeutic efficacy of CGM on metabolic control using two different statistical methods: linear regression and survival analysis; (2) to demonstrate the particular advantages of each statistical method. METHODS: A total of 42 persons with diabetes mellitus treated by means of an insulin pump participated in this study. According to the means of selfmonitoring persons with diabetes were divided into two groups: 1. intervention group of 17 persons using CGM, 2. control group of 25 persons using a glucometer. Each person was followed for a period of three months. At the beginning of the study and at the end of each month HbA1c was determined. RESULTS: Both the regression analysis and survival analysis brought evidence of significant changes of the HbA1c in either of the groups. The method of linear regression enables to analyse the evolution of HbA1c in each individual person followed by comparison of the groups. The survival analysis demonstrated that the probability of HbA1c decrease to the predefined level as well as its further maintaining at this level was higher in the CGM group. The mean time interval necessary to HbA1c decrease was shorter in the CGM group. CONCLUSIONS: The efficacy of CGM was demonstrated. In addition to linear regression, survival analysis appears to be an useful complementary method in the statistical evaluation of the treatment efficacy.

• MeSH
• ambulantní monitorování * MeSH
• analýza přežití MeSH
• diabetes mellitus 1. typu krev   farmakoterapie   MeSH
• dospělí MeSH
• glykovaný hemoglobin analýza   MeSH
• inzulinové infuzní systémy MeSH
• lidé středního věku MeSH
• lidé MeSH
• lineární modely MeSH
• mladý dospělý MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• glykovaný hemoglobin MeSH

Field crops represent one of the highest contributions to dietary metal exposure. The aim of this study was to develop specific regression models for the uptake of metals into various field crops and to compare the usability of other available models. We analysed samples of potato, hop, maize, barley, wheat, rape seed, and grass from 66 agricultural sites. The influence of measured soil concentrations and soil factors (pH, organic carbon, content of silt and clay) on the plant concentrations of Cd, Cr, Cu, Mo, Ni, Pb and Zn was evaluated. Bioconcentration factors (BCF) and plant-specific metal models (PSMM) developed from multivariate regressions were calculated. The explained variability of the models was from 19 to 64% and correlations between measured and predicted concentrations were between 0.43 and 0.90. The developed hop and rapeseed models are new in this field. Available models from literature showed inaccurate results, except for Cd; the modelling efficiency was mostly around zero. The use of interaction terms between parameters can significantly improve plant-specific models.

• Klíčová slova
• Field crops, Heavy metals, Linear regression, Plant uptake, Prediction models,
• MeSH
• Brassica rapa chemie   MeSH
• kontaminace potravin MeSH
• kukuřice setá chemie   MeSH
• látky znečišťující půdu analýza   MeSH
• monitorování životního prostředí metody   statistika a číselné údaje   MeSH
• multivariační analýza MeSH
• pšenice chemie   MeSH
• půda chemie   MeSH
• regresní analýza MeSH
• teoretické modely * MeSH
• těžké kovy analýza   MeSH
• zemědělské plodiny chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• látky znečišťující půdu MeSH
• půda MeSH
• těžké kovy MeSH