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: 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

BACKGROUND: All currently available methods of network/association inference from microarray gene expression measurements implicitly assume that such measurements represent the actual expression levels of different genes within each cell included in the biological sample under study. Contrary to this common belief, modern microarray technology produces signals aggregated over a random number of individual cells, a "nitty-gritty" aspect of such arrays, thereby causing a random effect that distorts the correlation structure of intra-cellular gene expression levels. RESULTS: This paper provides a theoretical consideration of the random effect of signal aggregation and its implications for correlation analysis and network inference. An attempt is made to quantitatively assess the magnitude of this effect from real data. Some preliminary ideas are offered to mitigate the consequences of random signal aggregation in the analysis of gene expression data. CONCLUSION: Resulting from the summation of expression intensities over a random number of individual cells, the observed signals may not adequately reflect the true dependence structure of intra-cellular gene expression levels needed as a source of information for network reconstruction. Whether the reported effect is extrime or not, the important point, is to reconize and incorporate such signal source for proper inference. The usefulness of inference on genetic regulatory structures from microarray data depends critically on the ability of investigators to overcome this obstacle in a scientifically sound way. REVIEWERS: This article was reviewed by Byung Soo KIM, Jeanne Kowalski and Geoff McLachlan.

• MeSH
• lidé MeSH
• modely genetické * MeSH
• neparametrická statistika MeSH
• sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů metody   statistika a číselné údaje   MeSH
• stanovení celkové genové exprese metody   statistika a číselné údaje   MeSH
• výpočetní biologie metody   statistika a číselné údaje   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, N.I.H., Extramural MeSH

BACKGROUND: Obstructive sleep apnoea (OSA) is considered an important risk factor of cardiovascular diseases (CVDs). Epicardial fat (EF) thickness and adipocyte fatty acid-binding protein (A-FABP) may be important links to accelerated atherosclerosis observed in patients with OSA. The aim was to evaluate the relationship between EF thickness and A-FABP levels in patients with OSA. METHODS: 66 patients (of which, 60 were males) of average age 55.6 ± 8.8 years, with newly diagnosed OSA were enrolled in this study. All patients underwent a sleep study, anthropometric parameters were measured, laboratory analysis and echocardiography with EF thickness measurements were collected. Patients were divided into two groups: Group 1: EF < 1mm; Group 2: EF > 1mm. RESULTS: Epicardial fat was present in 51 patients (77.3%). A positive correlation was found between A-FABP levels and % of body fat (r=0.452, p=0.0002). After adjusting to % of body fat, there was no significant difference found in A-FABP levels in the two groups divided. CONCLUSIONS: This study found a positive correlation between serum A-FABP level and % of body fat in patients with moderate to severe obstructive sleep apnoea. No significant difference was found between both groups.

• MeSH
• antropometrie metody   MeSH
• dospělí MeSH
• index tělesné hmotnosti MeSH
• kardiovaskulární nemoci krev   MeSH
• lidé středního věku MeSH
• lidé MeSH
• obezita metabolismus   MeSH
• obstrukční spánková apnoe krev   MeSH
• předběžné údaje MeSH
• proteiny vázající mastné kyseliny krev   MeSH
• rizikové faktory MeSH
• tuková tkáň metabolismus   MeSH
• tukové buňky metabolismus   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• proteiny vázající mastné kyseliny 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 use random matrix theory to demonstrate the existence of generic and subject-independent features of the ensemble of correlation matrices extracted from human EEG data. In particular, the spectral density as well as the level spacings was analyzed and shown to be generic and subject independent. We also investigate number variance distributions. In this case we show that when the measured subject is visually stimulated the number variance displays deviations from the random matrix prediction.

• MeSH
• elektroencefalografie metody   MeSH
• interpretace statistických dat * MeSH
• lidé MeSH
• statistické modely * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

OBJECTIVES: The aim of the study was to create an index of socio-economic deprivation (SESDI) and to analyse correlation between SESDI and mortality data. METHODS: The SESDI components were selected from the census data (2001) at enumeration district and district level. Two methods were used for creating the SESDI: 1/ a sum of Z-scores of specific components (INDEX1); and 2/ standardized score - average values of specific components were divided by a maximum value of the specific component at the corresponding geographical level (INDEX2). Pearson's correlation coefficient was used for assessing the relationship between indices, and between indices and mortality data (SMR). RESULTS: The final indices were applied to districts in the Czech Republic (N = 77). The correlation of INDEX1 and INDEX2 was high (r = 0.99). Analysis of relationships between degree of deprivation and total and selected specific SMR in the Czech Republic confirmed that mortality was associated with degree of deprivation. CONCLUSION: The use of socio-economic deprivation indices in analysis of routinely collected mortality data in public health might help to explain health inequalities.

• MeSH
• chudoba * MeSH
• disparity zdravotního stavu * MeSH
• lidé MeSH
• mortalita trendy   MeSH
• sčítání lidu MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH

SUMMARY: Untargeted liquid chromatography-high-resolution mass spectrometry analysis produces a large number of features which correspond to the potential compounds in the sample that is analyzed. During the data processing, it is necessary to merge features associated with one compound to prevent multiplicities in the data and possible misidentification. The processing tools that are currently employed use complex algorithms to detect abundances, such as adducts or isotopes. However, most of them are not able to deal with unpredictable adducts and in-source fragments. We introduce a simple open-source R-script CROP based on Pearson pairwise correlations and retention time together with a graphical representation of the correlation network to remove these redundant features. AVAILABILITY AND IMPLEMENTATION: The CROP R-script is available online at www.github.com/rendju/CROP under GNU GPL. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

• MeSH
• algoritmy MeSH
• chromatografie kapalinová MeSH
• hmotnostní spektrometrie MeSH
• metabolomika * MeSH
• software * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The Minimum Redundancy Maximum Relevance (MRMR) approach to supervised variable selection represents a successful methodology for dimensionality reduction, which is suitable for high-dimensional data observed in two or more different groups. Various available versions of the MRMR approach have been designed to search for variables with the largest relevance for a classification task while controlling for redundancy of the selected set of variables. However, usual relevance and redundancy criteria have the disadvantages of being too sensitive to the presence of outlying measurements and/or being inefficient. We propose a novel approach called Minimum Regularized Redundancy Maximum Robust Relevance (MRRMRR), suitable for noisy high-dimensional data observed in two groups. It combines principles of regularization and robust statistics. Particularly, redundancy is measured by a new regularized version of the coefficient of multiple correlation and relevance is measured by a highly robust correlation coefficient based on the least weighted squares regression with data-adaptive weights. We compare various dimensionality reduction methods on three real data sets. To investigate the influence of noise or outliers on the data, we perform the computations also for data artificially contaminated by severe noise of various forms. The experimental results confirm the robustness of the method with respect to outliers.

• MeSH
• algoritmy * MeSH
• interpretace statistických dat * MeSH
• lidé MeSH
• metabolomika MeSH
• proteomika * MeSH
• regulace genové exprese genetika   MeSH
• teoretické modely * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In 2011 and 2012, the COPHES/DEMOCOPHES twin projects performed the first ever harmonized human biomonitoring survey in 17 European countries. In more than 1800 mother-child pairs, individual lifestyle data were collected and cadmium, cotinine and certain phthalate metabolites were measured in urine. Total mercury was determined in hair samples. While the main goal of the COPHES/DEMOCOPHES twin projects was to develop and test harmonized protocols and procedures, the goal of the current paper is to investigate whether the observed differences in biomarker values among the countries implementing DEMOCOPHES can be interpreted using information from external databases on environmental quality and lifestyle. In general, 13 countries having implemented DEMOCOPHES provided high-quality data from external sources that were relevant for interpretation purposes. However, some data were not available for reporting or were not in line with predefined specifications. Therefore, only part of the external information could be included in the statistical analyses. Nonetheless, there was a highly significant correlation between national levels of fish consumption and mercury in hair, the strength of antismoking legislation was significantly related to urinary cotinine levels, and we were able to show indications that also urinary cadmium levels were associated with environmental quality and food quality. These results again show the potential of biomonitoring data to provide added value for (the evaluation of) evidence-informed policy making.

• Klíčová slova
• COPHES, DEMOCOPHES, External exposure data, Human biomonitoring, Interpretation,
• MeSH
• biologické markery analýza   moč   MeSH
• dítě MeSH
• dospělí MeSH
• interpretace statistických dat MeSH
• kadmium analýza   moč   MeSH
• kotinin moč   MeSH
• kouření zákonodárství a právo   moč   MeSH
• látky znečišťující životní prostředí analýza   moč   MeSH
• lidé MeSH
• městské obyvatelstvo statistika a číselné údaje   MeSH
• monitorování životního prostředí metody   statistika a číselné údaje   MeSH
• potrava z moře (živočišná) statistika a číselné údaje   MeSH
• průzkumy a dotazníky normy   MeSH
• rtuť analýza   moč   MeSH
• venkovské obyvatelstvo statistika a číselné údaje   MeSH
• vládní regulace MeSH
• vlasy, chlupy chemie   MeSH
• vystavení vlivu životního prostředí analýza   statistika a číselné údaje   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH
• Názvy látek
• biologické markery MeSH
• kadmium MeSH
• kotinin MeSH
• látky znečišťující životní prostředí MeSH
• rtuť MeSH