nonlinear control
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This study was aimed to analyse the lower limb kinematics during the change of direction (COD) performance with the dominant (DL) and non-dominant (NDL) leg using linear (traditional kinematics) and nonlinear (Self Organising Map-based cluster analysis) approaches. Three 5-0-5 COD performances with the DL and three with the NDL were performed by 23 (aged 21.6 ± 2.3 years) collegiate athletes. No significant difference was observed between the COD duration, and approach speed of DL and NDL. Significantly greater ankle abductions, knee and hip external rotations were identified in COD with DL, compared to NDL (p < .001, d > 0.8). Self Organising Maps portrayed a completely different coordination pattern profile during change of direction performance with the DL and NDL. The cluster analysis illustrated similar inter-individual coordination patterning when participants turned with their DL or NDL. No visible relationship was observed in the cluster analysis of the lower limb joint angles and angular velocities. Outcomes of this study portrayed that coordination patterning (combination of joint angles and the rate of change of angles) could portray the movement patterning differences in different tasks, while a sole investigation on the joint angles or angular velocities may not reveal the underlying mechanisms of movement patterning.
- MeSH
- bérec * fyziologie MeSH
- biomechanika MeSH
- dolní končetina * fyziologie MeSH
- funkční lateralita * fyziologie MeSH
- kotník fyziologie MeSH
- lidé MeSH
- mladý dospělý MeSH
- motorické dovednosti * fyziologie MeSH
- nelineární dynamika MeSH
- pohyb fyziologie MeSH
- shluková analýza MeSH
- sportovní výkon * fyziologie MeSH
- Check Tag
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Restless legs syndrome (RLS) affects up to 10% of older adults. Their healthcare is impeded by delayed diagnosis and insufficient treatment. To advance disease prediction and find new entry points for therapy, we performed meta-analyses of genome-wide association studies in 116,647 individuals with RLS (cases) and 1,546,466 controls of European ancestry. The pooled analysis increased the number of risk loci eightfold to 164, including three on chromosome X. Sex-specific meta-analyses revealed largely overlapping genetic predispositions of the sexes (rg = 0.96). Locus annotation prioritized druggable genes such as glutamate receptors 1 and 4, and Mendelian randomization indicated RLS as a causal risk factor for diabetes. Machine learning approaches combining genetic and nongenetic information performed best in risk prediction (area under the curve (AUC) = 0.82-0.91). In summary, we identified targets for drug development and repurposing, prioritized potential causal relationships between RLS and relevant comorbidities and risk factors for follow-up and provided evidence that nonlinear interactions are likely relevant to RLS risk prediction.
- MeSH
- celogenomová asociační studie * MeSH
- genetická predispozice k nemoci * MeSH
- jednonukleotidový polymorfismus MeSH
- lidé MeSH
- mendelovská randomizace MeSH
- rizikové faktory MeSH
- strojové učení MeSH
- syndrom neklidných nohou * genetika MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- metaanalýza MeSH
It is important for older and disabled people who live alone to be able to cope with the daily challenges of living at home. In order to support independent living, the Smart Home Care (SHC) concept offers the possibility of providing comfortable control of operational and technical functions using a mobile robot for operating and assisting activities to support independent living for elderly and disabled people. This article presents a unique proposal for the implementation of interoperability between a mobile robot and KNX technology in a home environment within SHC automation to determine the presence of people and occupancy of occupied spaces in SHC using measured operational and technical variables (to determine the quality of the indoor environment), such as temperature, relative humidity, light intensity, and CO2 concentration, and to locate occupancy in SHC spaces using magnetic contacts monitoring the opening/closing of windows and doors by indirectly monitoring occupancy without the use of cameras. In this article, a novel method using nonlinear autoregressive Neural Networks (NN) with exogenous inputs and nonlinear autoregressive is used to predict the CO2 concentration waveform to transmit the information from KNX technology to mobile robots for monitoring and determining the occupancy of people in SHC with better than 98% accuracy.
- MeSH
- lidé MeSH
- oxid uhličitý MeSH
- robotika * metody MeSH
- samostatný způsob života MeSH
- senioři MeSH
- služby domácí péče * MeSH
- technologie MeSH
- Check Tag
- lidé MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
Background: Children's creativity and motor competence are expandable factors that are related to convergent and divergent thinking processes. Objective: This study aimed to investigate the effect of games based on divergent and convergent thinking on motor competence and creativity in children aged 7-8 years. Methods: Participants aged 7.41 ± 0.39 years (n = 34) were selected based on inclusion criteria and were divided randomly into three groups (divergent thinking, convergent thinking, and control). Participants performed their group interventions in eighteen training sessions (six weeks period). The nonlinear training approach was used to manipulate divergent thinking and linear training was used in the group of manipulating convergent thinking. Each child completed the Movement Assessment Battery for Children - Second Edition to assess motor competence. The Bertsch Test was used to assess motor creativity. Results: In motor competence, the results revealed significant main effects for groups (p < .001) and time (p < .001) as well as significant groups by time interaction effect (p < .001). The divergent thinking group (M = 32.50) was significantly better than the control group (M = 24.79, p < .001), and the convergent thinking group (M = 28.81, p = .003). In motor creativity, the results revealed significant main effects for groups (p < .001) and time (p < .001) as well as significant groups by time interaction effect (p < .001). The divergent thinking group (M = 13.27, p < .001) and the convergent thinking group (M = 12.36, p = .016) were significantly better than the control group (M = 10.63). However, no significant difference was found between the divergent thinking and convergent thinking groups. Conclusions: Physical education teachers and educators are recommended to use the divergent thinking training approach to promote students' motor competence. Also, simple adjustments in the exercise program in the form of games can help children's motor creativity. However, more research is suggested to explore divergent and convergent learning mechanisms.
- Klíčová slova
- divergent thinking, convergent thinking,
- MeSH
- kreativita MeSH
- motorické dovednosti MeSH
- myšlení * klasifikace MeSH
- techniky cvičení a pohybu metody psychologie MeSH
- tělesná výchova * MeSH
- Publikační typ
- klinická studie MeSH
Mobile wireless communication technologies have now become an everyday part of our lives, 24 hours a day, 7 days a week. Monitoring the autonomous system under exposition to electromagnetic fields may play an important role in broading of our still limited knowledge on their effect on human body. Thus, we studied the interaction of the high frequency electromagnetic field (HF EMF) with living body and its effect on the autonomic control of heart rate using Heart Rate Variability (HRV) linear and nonlinear analyses in healthy volunteers. A group of young healthy probands (n=30, age mean: 24.2 ± 3.5 years) without any symptoms of disease was exposed to EMF with f=2400 MHz (Wi Fi), and f=2600 MHz (4G) for 5 minutes applied on the chest area. The short-term heart rate variability (HRV) metrics were used as an indicator of complex cardiac autonomic control. The evaluated HRV parameters: RR interval (ms), high frequency spectral power (HF-HRV in [ln(ms2)]) as an index of cardiovagal control, and a symbolic dynamic index of 0V %, indicating cardiac sympathetic activity. The cardiac-linked parasympathetic index HF-HRV was significantly reduced (p =0.036) and sympathetically mediated HRV index 0V % was significantly higher (p=0.002) during EMF exposure at 2400 MHz (Wi-Fi), compared to simulated 4G frequency 2600 MHz. No significant differences were found in the RR intervals. Our results revealed a shift in cardiac autonomic regulation towards sympathetic overactivity and parasympathetic underactivity indexed by HRV parameters during EMF exposure in young healthy persons. It seems that HF EMF exposure results in abnormal complex cardiac autonomic regulatory integrity which may be associated with higher risk of later cardiovascular complications already in healthy probands.
- MeSH
- autonomní nervový systém MeSH
- dospělí MeSH
- elektromagnetická pole * škodlivé účinky MeSH
- kardiovaskulární nemoci * MeSH
- lidé MeSH
- mladý dospělý MeSH
- rizikové faktory kardiovaskulárních chorob MeSH
- rizikové faktory MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- Publikační typ
- časopisecké články MeSH
There are substantial differences in autonomic nervous system activation among heart (cardiac) failure (CF) patients. The effect of acute CF on autonomic function has not been well explored. The aim of our study was to assess the effect of experimental acute CF on heart rate variability (HRV). Twenty-four female pigs with a mean body weight of 45 kg were used. Acute severe CF was induced by global myocardial hypoxia. In each subject, two 5-min electrocardiogram segments were analyzed and compared: before the induction of myocardial hypoxia and >60 min after the development of severe CF. HRV was assessed by time-domain, frequency-domain and nonlinear analytic methods. The induction of acute CF led to a significant decrease in cardiac output, left ventricular ejection fraction and an increase in heart rate. The development of acute CF was associated with a significant reduction in the standard deviation of intervals between normal beats (50.8 [20.5−88.1] ms versus 5.9 [2.4−11.7] ms, p < 0.001). Uniform HRV reduction was also observed in other time-domain and major nonlinear analytic methods. Similarly, frequency-domain HRV parameters were significantly changed. Acute severe CF induced by global myocardial hypoxia is associated with a significant reduction in HRV.
Background and objective: Non-adherence to tacrolimus commonly manifests as low drug concentrations and/or high intra-patient variability (IPV) of concentrations across multiple measurements. We aimed to compare several methods of tacrolimus IPV calculation and evaluate how well each reflects blood concentration variation due to medication non-adherence in kidney transplant recipients. Methods: This Czech single-center retrospective longitudinal study was conducted in 2019. All outpatients ≥18 years of age, ≥3 months post-transplant, and on tacrolimus-based regimens were approached. After collecting seven consecutive tacrolimus concentrations we asked participating patients to self-report adherence to immunosuppressants (BAASIS© scale). The IPV of tacrolimus was calculated as the medication level variability index (MLVI), the coefficient of variation (CV), the time-weighted CV, and via nonlinearly modeled dose-corrected trough levels. These patient-level variables were analyzed using regression analysis. Detected nonlinearities in the dose-response curve were controlled for by adding tacrolimus dosing and its higher-order terms as covariates, along with self-reported medication adherence levels. Results: Of 243 patients using tacrolimus, 42% (n = 102) reported medication non-adherence. Non-adherence was associated with higher CVs, higher time-weighted CVs, and lower dose-corrected nonlinearly modeled trough levels; however, it was not associated with MLVIs. All of the significant operationalizations suggested a weak association that was similar across the applied methods. Discussion and conclusion: Implementation non-adherence was reflected by higher CV or time-weighted CV and by lower blood concentrations of tacrolimus. As an additional tool for identifying patients at risk for non-adherence, simple IPV calculations incorporated into medical records should be considered in everyday clinical practice.
- Publikační typ
- časopisecké články MeSH
Blood flows and pressures throughout the human cardiovascular system are regulated in response to various dynamic perturbations, such as changes to peripheral demands in exercise, rapid changes in posture, or loss of blood from hemorrhage, via the coordinated action of the heart, the vasculature, and autonomic reflexes. To assess how the systemic and pulmonary arterial and venous circulation, the heart, and the baroreflex work together to effect the whole-body responses to these perturbations, we integrated an anatomically-based large-vessel arterial tree model with the TriSeg heart model, models capturing nonlinear characteristics of the large and small veins, and baroreflex-mediated regulation of vascular tone and cardiac chronotropy and inotropy. The model was identified by matching data from the Valsalva maneuver (VM), exercise, and head-up tilt (HUT). Thirty-one parameters were optimized using a custom parameter-fitting tool chain, resulting in an unique, high-fidelity whole-body human cardiovascular systems model. Because the model captures the effects of exercise and posture changes, it can be used to simulate numerous clinical assessments, such as HUT, the VM, and cardiopulmonary exercise stress testing. The model can also be applied as a framework for representing and simulating individual patients and pathologies. Moreover, it can serve as a framework for integrating multi-scale organ-level models, such as for the heart or the kidneys, into a whole-body model. Here, the model is used to analyze the relative importance of chronotropic, inotropic, and peripheral vascular contributions to the whole-body cardiovascular response to exercise. It is predicted that in normal physiological conditions chronotropy and inotropy make roughly equal contributions to increasing cardiac output and cardiac power output during exercise. Under upright exercise conditions, the nonlinear pressure-volume relationship of the large veins and sympathetic-mediated venous vasoconstriction are both required to maintain preload to achieve physiological exercise levels. The developed modeling framework is built using the open Modelica modeling language and is freely distributed.
- MeSH
- baroreflex * fyziologie MeSH
- cvičení * MeSH
- kardiovaskulární systém * MeSH
- krevní tlak fyziologie MeSH
- lidé MeSH
- postura těla fyziologie MeSH
- srdeční frekvence fyziologie MeSH
- systémová analýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
In this work, we carried out neurochemical and behavioral analysis of zebrafish (Danio rerio) treated with rotenone, an agent used to chemically induce a syndrome resembling Parkinson's disease (PD). Dopamine release, measured with fast-scan cyclic voltammetry (FSCV) at carbon-fiber electrodes in acutely harvested whole brains, was about 30% of that found in controls. Uptake, represented by the first order rate constant (k) and the half-life (t1/2) determined by nonlinear regression modeling of the stimulated release plots, was also diminished. Behavioral analysis revealed that rotenone treatment increased the time required for zebrafish to reach a reward within a maze by more than 50% and caused fish to select the wrong pathway, suggesting that latent learning was impaired. Additionally, zebrafish treated with rotenone suffered from diminished locomotor activity, swimming shorter distances with lower mean velocity and acceleration. Thus, the neurochemical and behavioral approaches, as applied, were able to resolve rotenone-induced differences in key parameters. This approach may be effective for screening therapies in this and other models of neurodegeneration.
- MeSH
- dánio pruhované metabolismus MeSH
- dopamin metabolismus MeSH
- kognice MeSH
- modely nemocí na zvířatech MeSH
- Parkinsonova nemoc * MeSH
- rotenon * farmakologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Evaluation of safety performance remains central to any safety and risk management. Currently, there are very few support tools and methods which allow for quantitative approach in this domain. One of the successful methods available to this end is the Aerospace Performance Factor (APF). The method is based on hierarchical clustering of taxonomy-based safety performance indicators, using simple and intelligible formula to compute the overall safety performance signal. The work presented in this study deals with one of the APF shortcomings, namely the absence of nonlinear relations among the performance indicators to capture more accurately the risk in the assessed system. It proposes an addition of new decision criteria behind the APF method as part of the application of Analytical Hierarchy Process (AHP), namely the impact of respective performance indicator on other indicators, regardless of their hierarchical structure. This addition leads to relative changes of performance indicators significance, where those with the highest potential for nonlinear interactions among the entire set of performance indicators are emphasized and the change in their weight ultimately leads to changes in the overall APF signal. The study results indicate that the extended APF signal is refined in terms of extremes and it draws more accurate picture about the actual safety performance, eventually supporting better identification of deviations from its acceptable values. The study was experimentally carried out in the aviation with data from the European Central Repository (ECR) originating from United Kingdom during the years 2013-2015 and verified further on data sets from Finland and Denmark.
- MeSH
- letectví * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Spojené království MeSH
