Most data in environmental sciences and geochemistry are compositional. Already the unit used to report the data (e.g., μg/l, mg/kg, wt%) implies that the analytical results for each element are not free to vary independently of the other measured variables. This is often neglected in statistical analysis, where a simple log-transformation of the single variables is insufficient to put the data into an acceptable geometry. This is also important for bivariate data analysis and for correlation analysis, for which the data need to be appropriately log-ratio transformed. A new approach based on the isometric log-ratio (ilr) transformation, leading to so-called symmetric coordinates, is presented here. Summarizing the correlations in a heat-map gives a powerful tool for bivariate data analysis. Here an application of the new method using a data set from a regional geochemical mapping project based on soil O and C horizon samples is demonstrated. Differences to 'classical' correlation analysis based on log-transformed data are highlighted. The fact that some expected strong positive correlations appear and remain unchanged even following a log-ratio transformation has probably led to the misconception that the special nature of compositional data can be ignored when working with trace elements. The example dataset is employed to demonstrate that using 'classical' correlation analysis and plotting XY diagrams, scatterplots, based on the original or simply log-transformed data can easily lead to severe misinterpretations of the relationships between elements.

• Klíčová slova
• CoDa, Compositional data analysis, Correlation, Log-ratio methodology, Scatterplot,
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Medication administration errors (MAE) are a worldwide issue affecting the safety of hospitalized patients. Through the early identification of potential causes, it is possible to increase the safety of medication administration (MA) in clinical nursing. The study aimed to identify potential risk factors affecting drug administration in inpatient wards in the Czech Republic. MATERIAL AND METHODS: A descriptive correlation study through a non-standardized questionnaire was used. Data were collected from September 29 to October 15, 2021, from nurses in the Czech Republic. For statistical analysis, the authors used SPSS vers. 28 (IBM Corp., Armonk, NY, USA). RESULTS: The research sample consisted of 1205 nurses. The authors found that there was a statistically significant relationship between nurse education (p = 0.05), interruptions, preparation of medicines outside the patient rooms (p < 0.001), inadequate patient identification (p < 0.01), large numbers of patients assigned per nurse (p < 0.001), use of team nursing care and administration of generic substitution and an MAE. CONCLUSIONS: The results of the study point to the weaknesses of medication administration in selected clinical departments in hospitals. The authors found that several factors, such as high patient ratio per nurse, lack of patient identification, and interruption during medication preparation of nurses, can increase the prevalence of MAE. Nurses who have completed MSc and PhD education have a lower incidence of MAE. More research is needed to identify other causes of medication administration errors. Improving the safety culture is the most critical challenge for today's healthcare industry. Education for nurses can be an effective way to reduce MAEs by enhancing their knowledge and skills, mainly focusing on increasing adherence to safe medication preparation and administration and a better understanding of medication pharmacodynamics. Med Pr. 2023;74(2):85-92.

• Klíčová slova
• drug, errors, medication administration, nursing, patient safety, safety management,
• MeSH
• korelace dat MeSH
• léčivé přípravky MeSH
• lidé MeSH
• medikační omyly * prevence a kontrola   MeSH
• průzkumy a dotazníky MeSH
• zpráva o sobě MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• léčivé přípravky MeSH

We present a technique employing a speckle pattern correlation method for detection of the slope of an object's surface. Controlled translation of an object under investigation and numerical correlation of speckle patterns recorded during its motion give information used to evaluate the tilt of the object. The proposed optical setup uses a symmetrical arrangement of detection planes in the image field and enables one to detect the tilt of an object's surface within the interval (10 degrees-30 degrees). Simulation analysis shows how to control the measuring range. The presented theory, simulation analysis, and setup are verified through an experiment by measurement of the slope of a surface of a cube made out of steel.

• Publikační typ
• časopisecké články MeSH

We present a measurement of an object's in-plane velocity in one direction by the use of the speckle correlation method. Numerical correlations of speckle patterns recorded periodically during motion of the object under investigation give information used to evaluate the object's in-plane velocity. The proposed optical setup uses a detection plane in the image field and enables one to detect the object's velocity within the interval (10-150) microm x s(-1). Simulation analysis shows a way of controlling the measuring range. The presented theory, simulation analysis, and setup are verified through an experiment of measurement of the velocity profile of an object.

• MeSH
• časové faktory MeSH
• design vybavení MeSH
• fyzika metody   MeSH
• kovy MeSH
• lasery MeSH
• mikroskopie přístrojové vybavení   metody   MeSH
• optika a fotonika * MeSH
• počítačové zpracování obrazu MeSH
• pohyb těles MeSH
• statistické modely MeSH
• teoretické modely MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kovy MeSH

The interaction between fluorescently labeled hyaluronan and cationic surfactants was studied using Fluorescence Correlation Spectroscopy. The hyaluronan was selected at two different molecular weights - specifically, 274 kDa and 710 kDa. Cetyltrimethylammonium bromide and Septonex® were chosen as cationic surfactants to interact with the negatively charged biopolymer. The study focused on changes in the diffusive behavior of a biopolymer that interacts with surfactant molecules in an aqueous environment. Various methods were applied to evaluate the obtained data, these including, among others, the Maximum Entropy Method, which provides the distributional dependences of diffusion coefficients. Without the surfactant, the studied biopolymers showed diffusion behavior comparable to that found in previously published studies. In the presence of surfactants, more intense interaction was observed between Cetyltrimethylammonium bromide and Septonex®. Comparing the molecular weights, the retention of intermolecular aggregates after the precipitation region for the lower weight and the disintegration of these aggregates for the higher weight were observed; moreover, they showed diffusion behavior comparable to the samples without the presence of the surfactant.

• Klíčová slova
• Cetyltrimethylammonium bromide, Fluorescence correlation spectroscopy, Hyaluronan, Maximum entropy method, Septonex®,
• MeSH
• biopolymery MeSH
• cetrimonium MeSH
• fluorescenční spektrometrie MeSH
• kvartérní amoniové sloučeniny * MeSH
• kyselina hyaluronová * chemie   MeSH
• povrchově aktivní látky * chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biopolymery MeSH
• cetrimonium MeSH
• kvartérní amoniové sloučeniny * MeSH
• kyselina hyaluronová * MeSH
• povrchově aktivní látky * MeSH
• Septonex MeSH Prohlížeč

The principles of a new α-shift correlation (ASC) NMR method are demonstrated on a model series of substituted derivatives of o-carborane for which reliable NMR data are available. This graphical method revealed an acceptable linear correlation between α(11B) or α(13C) shifts and those induced by substituents in unsubstituted (u) positions of the carborane cluster. The linearity holds for all nuclei involved in skeletal bonding: Δδ(N)u = g × α (where N = 11B, 13C, and 1H). The factor g (slope of the correlation line × 102) becomes an important measure of sensitivity of a given cage position to substituent changes. The β, γ, and δ = A (= antipodal) shifts can be therefore derived from the α-shift, are linearly proportional, and reflect additive character in double substitution. The ASC method appears to be an important tool for quantitative assessment of substituent NMR effects in all exo-substituted boron-cluster systems.

• Publikační typ
• časopisecké články MeSH

The purpose of the study is to show a proposal of an extension of a one-dimensional speckle correlation method, which is primarily intended for determination of one-dimensional object's translation, for detection of general in-plane object's translation. In that view, a numerical simulation of a displacement of the speckle field as a consequence of general in-plane object's translation is presented. The translation components a x and a y representing the projections of a vector a of the object's displacement onto both x- and y-axes in the object plane (x, y) are evaluated separately by means of the extended one-dimensional speckle correlation method. Moreover, one can perform a distinct optimization of the method by reduction of intensity values representing detected speckle patterns. The theoretical relations between the translation components a x and a y of the object and the displacement of the speckle pattern for selected geometrical arrangement are mentioned and used for the testifying of the proposed method's rightness.

• MeSH
• pohyb těles * MeSH
• teoretické modely * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The work deals with the detection and localization of impact damage in a carbon fibre reinforced thermoplastic composite using Lamb wave type of ultrasonic guided waves. The attention is paid to the universality and robustness of the evaluation process with emphasis on a frequency-integral method. The approach is presented on the composite plate subjected to the sequence of two impacts caused damage. The damage indication utilizes relative time-of-flight delays and the subsequent localization task introduces a novel correlation coefficient for damage indices used in RAPID visualisation algorithm. Generally, the selection of a suitable mode and actuating frequency is essential for the evaluation. On the contrary, it is shown that integral evaluation over wider frequency range works well and can eliminate inappropriate frequencies and other difficulties. The approach provides an overall view of the response of the measured composite plate in conjunction with the inspection system. The capability of the frequency-integral method is shown to be unlike the conventional evaluation process, which involves a chain of steps from Lamb wave tuning, identification of a particular wave packet, to damage determination. The method was implemented into LaWaI GUI (Lamb Waves Inspection Graphical User Interface) to automate the processing.

• Klíčová slova
• Composite, Correlation coefficient, Frequency-integral method, Impact damage, Lamb waves, Multi-frequency approach, Time-of-flight,
• Publikační typ
• časopisecké články MeSH

The performance of a pharmaceutical formulation, such as the drug (API) release rate, is significantly influenced by the properties of the materials used, the composition of the final product and the tablet compression process parameters. However, in some cases, the knowledge of these input parameters does not necessarily provide a reliable description or prediction of tablet performance. Therefore, the knowledge of tablet microstructure is desirable to understand such formulations. Commonly used analytical techniques, such as X-ray tomography and intrusion mercury porosimetry, are not widely used in pharmaceutical companies due to their price and/or toxicity, and therefore, efforts are made to develop a tool for fast and easy microstructure description. In this work, we have developed an image-based method for microstructure description and applied it to a model system consisting of ibuprofen and CaHPO4∙2H2O (API and excipient with different deformability). The obtained parameter, the quadratic mean of the equivalent diameter of the non-deformable, brittle excipient CaHPO4∙2H2O, was correlated with tablet composition, compression pressure and API release rate. The obtained results demonstrate the possibility of describing the tablet dissolution performance in the presented model system based on the microstructural parameter, providing a possible model system for compressed solid dosage forms in which a plastic component is present and specific API release is required.

• Klíčová slova
• SEM image analysis, USP4 dissolution, deformability, flow-through dissolution, tablet microstructure,
• MeSH
• biologické modely * MeSH
• ibuprofen chemie   MeSH
• pomocné látky * chemie   MeSH
• příprava léků MeSH
• tablety chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ibuprofen MeSH
• pomocné látky * MeSH
• tablety MeSH

BACKGROUND: We report on the correlation between the proportion of people who fulfil the recommended amount of aerobic physical activity in the general population and the prevalence of frailty or prefrailty in the population ≥65 years in 11 European countries (Austria, Czech Republic, Denmark, Estonia, France, Germany, Italy, Luxembourg, Slovenia, Spain and Sweden). In a subgroup analysis, it was assessed if people who do aerobic physical activity also do strength training. METHODS: Aggregated physical activity data were taken from the European Health Interview Survey with the minimum effective sample size of 90,036 participants. Data on frailty status were taken from the Survey of Health Ageing and Retirement in Europe (SHARE) study (N = 24,590). For the subgroup analysis, data of the Austrian Health Interview Survey (ATHIS) (N = 15,770) were included. RESULTS: The results indicate a significant negative correlation between the proportion of people fulfilling the minimal aerobic physical activity recommendations (≥150 min/week) and the proportion of prefrail or frail people (R = -0.745; p = 0.008). The correlation between the optimal aerobic physical activity recommendations (≥300 min/week) and the proportion of prefrail or frail individuals was R = -0.691 (p = 0.019). In both data sets a north-south gradient was seen. Austrian data showed that 52.0% of the participants fulfilled the minimal aerobic physical activity recommendations and conducted strength training, whereas 18.4% did not fulfil the aerobic recommendations but performed strength training (p < 0.001). CONCLUSIONS: By taking into account that the number of people ≥65 years will increase in the future these results may be relevant in planning public health interventions for the whole population with the goal of reducing frailty in the elderly.

• Klíčová slova
• Aerobic physical activity recommendations, Demographic shift, Frailty, North-south gradient, Strength training,
• MeSH
• cvičení fyziologie   MeSH
• geriatrické hodnocení MeSH
• korelace dat MeSH
• křehkost * diagnóza   MeSH
• křehký senior * MeSH
• lidé MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• stárnutí fyziologie   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Evropa MeSH
• Itálie MeSH
• Německo MeSH
• Rakousko MeSH
• Slovinsko MeSH