Search results for "Statistic"
showing 10 items of 12520 documents
The number of contacts in random fibre networks
2012
There is a wide range of materials that can be considered as nonwoven random networks of fibres. Such materials include glass-fibre mats, filters, various paper products and structural components of cells and tissues. The mechanical properties of these kinds of networks have been studied extensively for many decades. As many of such networks form more or less two-dimensional structures, they can, to a good approximation, be considered to consist of randomly distributed fibres or filaments connected at their crossings points. Recent development of the resolution of X-ray computed tomography have enabled imaging of the three dimensional structure of such materials with a resolution sufficient…
Kinetic analysis of functional images: The case for a practical approach to performance prediction
1999
We present the first parallel medical application for the analysis of dynamic positron emission tomography (PET) images together with a practical performance model. The parallel application may improve the diagnosis for a patient (e. g. in epilepsy surgery) because it enables the fast computation of parametric images on a pixed level as opposed to the traditionally used region of interest (ROI) approach which is applied to determine an average parametric value for a particular anatomic region of the brain. We derive the performance model from the application context and show its relation to abstract machine models. We demonstrate the accuracy of the model to predict the runtime of the appli…
HEMATOLOGICAL VARIABILITY ANALYSIS AFTER ROAD MARATHON VS ULTRATRAIL. PREDICTIVE FACTORS
2020
The practice of long- and medium-distance races has exponentially increased the number of participants in recent years. They are carried out under extreme conditions that cause both biochemical and anthropometric changes in athletes and, in addition, have serious risks associated, such as dehydration, thermal disorders, or hypoglycemia. Knowledge regarding alterations at hematological level after this type of effort is limited. The objectives of this pre-post analytical descriptive observational study were: to describe and compare hematological values in amateur runners pre and post road marathon and ultratrail races, and to compare the hematological parameters between the groups in the two…
Reliability of a decision-tree model in predicting occupational lead poisoning in a group of highly exposed workers
2016
Objective This study aimed to provide the toxicological profile of some lead-exposed workers and obtain a predictive model for lead poisoning. Methods Data regarding external and absorbed exposure were collected from 585 subjects employed in ten metallurgical production departments. Airborne lead concentration, blood lead level (BLL), cumulative blood lead index (CBLI), urine delta-aminolevulinic acid (DALA), age, workplace/section, exposure period, and whether reported lead poisoning as occupational disease were examined using ANOVA, and, post-ANOVA, Pearson correlation matrix, PCA (principal component analysis), decision-tree modeling, and logistic modeling. Results BLL was less sensitive…
Estimating Heart Rate, Energy Expenditure, and Physical Performance With a Wrist Photoplethysmographic Device During Running
2017
BackgroundWearable sensors enable long-term monitoring of health and wellbeing indicators. An objective evaluation of sensors’ accuracy is important, especially for their use in health care. ObjectiveThe aim of this study was to use a wrist-worn optical heart rate (OHR) device to estimate heart rate (HR), energy expenditure (EE), and maximal oxygen intake capacity (VO2Max) during running and to evaluate the accuracy of the estimated parameters (HR, EE, and VO2Max) against golden reference methods. MethodsA total of 24 healthy volunteers, of whom 11 were female, with a mean age of 36.2 years (SD 8.2 years) participated in a submaximal self-paced outdoor running test and maximal voluntary exe…
Food consumption and nutrient intakes with a special focus on milk product consumption in early pubertal girls in Central Finland
2005
AbstractObjectiveTo evaluate the current status of dietary intakes in early pubertal girls with a special focus on milk products.DesignCross-sectional data using 3-day food records.SubjectsEight hundred and sixty girls, aged 10–12 years, at Tanner maturation stage I-III.ResultsThe mean consumption of milk products (620 g day−1) was similar to that of a Finnish study in the 1980s, while the consumption of non-milk drinks (403 gday−1) had increased. Twelve per cent of the girls had a dairy-restricted diet and consumed significantly less milk products than girls with a non-restricted diet (465 vs. 644 g day−1, P<0.001). Girls with low milk product consumption had the highest non-milk drinks…
How to remove the testing bias in CoV-2 statistics
2020
BACKGROUNDPublic health measures and private behaviour are based on reported numbers of SARS-CoV-2 infections. Some argue that testing influences the confirmed number of infections.OBJECTIVES/METHODSDo time series on reported infections and the number of tests allow one to draw conclusions about actual infection numbers? A SIR model is presented where the true numbers of susceptible, infectious and removed individuals are unobserved. Testing is also modelled.RESULTSOfficial confirmed infection numbers are likely to be biased and cannot be compared over time. The bias occurs because of different reasons for testing (e.g. by symptoms, representative or testing travellers). The paper illustrat…
El Instituto Médico Valenciano y la difusión de la vacuna
2004
The Medical Valencian Institute promoted a campaign of smallpox free vaccination (1851- 1894) by means of humanized vaccine sent from England. It spread the vaccination for the whole Spain and published careful statistics of the vaccinations practised in the Bulletin of the Medical Valencian Institute. The National Institute of Vaccination (1871) did not recognize his labor and one denied to him the category of Provincial Institute of Vaccination.
Contribution of parental and school personnel smoking to health risk behaviours among Finnish adolescents.
2009
Abstract Background This study compared parental smoking with school personnel smoking in relation to adolescents' smoking behaviours, alcohol use, and illicit drug use. Methods A cross-sectional survey for 24,379 adolescents was linked to a survey for 1946 school employees in 136 Finnish schools in 2004-2005. Surveys included smoking prevalence reported by school staff, adolescents' reports of school staff and parental smoking, adolescents' own smoking behaviours, alcohol use, and illicit drug use. Multilevel analyses were adjusted for individual and school-level confounding factors. Results Parental smoking was associated with all health risk behaviours among both sexes (risk range 1.39 t…
Effects of a school-based physical activity intervention on academic performance in 14-year old adolescents: a cluster randomized controlled trial – …
2021
Abstract Background School-based physical activity interventions evaluating the effect on academic performance usually includes children. We aimed to investigate the effect of a nine-month, school-based physical activity intervention titled School in Motion (ScIM) on academic performance in adolescents. Methods Thirty secondary schools in Norway were cluster-randomized into three groups: the Physically active learning (PAL) group (n = 10), the Don’t worry – Be Happy (DWBH) group (n = 10) or control (n = 10). Target dose in both intervention groups was 120 min/week of additional PA during school hours. Parental consent was obtained from 2084 adolescent students (76%). Standardized national t…