Bayesian regularization
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OBJECTIVE: To present a remodeling of the electroretinogram waveform using a covariance matrix to identify regions of interest and distinction between a control and attention deficit/hyperactivity disorder (ADHD) group. Electroretinograms were recorded in n = 25 ADHD (16 male; age 11.9 ± 2.7 years) and n = 38 (8 male; age 10.4 ± 2.8 years neurotypical control participants as part of a broad study into the determining if the electroretinogram could be a biomarker for ADHD. Flash strengths of 0.6 and 1.2 log cd.s.m- 2 on a white 40 cd.m- 2 background were used. Averaged waveforms from each eye and flash strength were analyzed with Bayesian regularization of the covariance matrices using 100 equal length time intervals. The eigenvalues of the covariance matrices were ranked for each group to indicate the degree of complexity within the regularized waveforms. RESULTS: The correlation matrices indicated less correlation within the waveforms for the ADHD group in time intervals beyond 70 msec. The eigenvalue plots suggest more complexity within the ADHD group compared to the control group. Consideration of the correlation structure between ERG waveforms from different populations may reveal additional features for identifying group differences in clinical populations.
- Klíčová slova
- Attention deficit hyperactivity disorder, Neurodevelopment, Retina, Time-domain ERG trajectory,
- MeSH
- Bayesova věta MeSH
- dítě MeSH
- elektroretinografie * metody MeSH
- hyperkinetická porucha * patofyziologie diagnóza MeSH
- lidé MeSH
- mladiství MeSH
- retina * patofyziologie MeSH
- studie případů a kontrol MeSH
- světelná stimulace MeSH
- světlo * MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
In this paper, we study the design aspects of an indoor visible light positioning (VLP) system that uses an artificial neural network (ANN) for positioning estimation by considering a multipath channel. Previous results usually rely on the simplistic line of sight model with limited validity. The study considers the influence of noise as a performance indicator for the comparison between different design approaches. Three different ANN algorithms are considered, including Levenberg-Marquardt, Bayesian regularization, and scaled conjugate gradient algorithms, to minimize the positioning error (εp) in the VLP system. The ANN design is optimized based on the number of neurons in the hidden layers, the number of training epochs, and the size of the training set. It is shown that, the ANN with Bayesian regularization outperforms the traditional received signal strength (RSS) technique using the non-linear least square estimation for all values of signal to noise ratio (SNR). Furthermore, in the inner region, which includes the area of the receiving plane within the transmitters, the positioning accuracy is improved by 43, 55, and 50% for the SNR of 10, 20, and 30 dB, respectively. In the outer region, which is the remaining area within the room, the positioning accuracy is improved by 57, 32, and 6% for the SNR of 10, 20, and 30 dB, respectively. Moreover, we also analyze the impact of different training dataset sizes in ANN, and we show that it is possible to achieve a minimum εp of 2 cm for 30 dB of SNR using a random selection scheme. Finally, it is observed that εp is low even for lower values of SNR, i.e., εp values are 2, 11, and 44 cm for the SNR of 30, 20, and 10 dB, respectively.
- Klíčová slova
- Bayesian regularization, artificial neural network (ANN), multipath reflections, non-linear least square, visible light communication (VLC), visible light positioning,
- MeSH
- algoritmy * MeSH
- Bayesova věta MeSH
- metoda nejmenších čtverců MeSH
- neuronové sítě * MeSH
- světlo MeSH
- Publikační typ
- časopisecké články MeSH
Acanthogyrus (Acanthosentis) maroccanus (Dollfus, 1951), an insufficiently described quadrigyrid acanthocephalan of cyprinid fishes from Northwest Africa, is redescribed based on recently collected specimens from the Algerian barb Luciobarbus callensis (Valenciennes) in Algeria. Newly observed morphological features for A. (A.) maroccanus include the arrangement of proboscis hooks (not in regular circles), the male reproductive structures extending into the copulatory bursa and the presence of a para-receptacle structure and vaginal sleeve. The mechanism of copulation of this acanthocephalan is described based on several copulating pairs. The phylogenetic position of A. (A.) maroccanus within Eoacanthocephala was assessed based on partial 28S rDNA sequences. Maximum likelihood and Bayesian inference analyses placed A. (A.) maroccanus in a clade with Palliolisentis (Demidueterospinus) ophiocephalus (Thapar, 1931), both species included in the Quadrigyridae, the only family within the Gyracanthocephala.
- Klíčová slova
- 28S rDNA, Acanthocephala, Eoacanthocephala, North Africa, freshwater fish, phylogeny, taxonomy,
- MeSH
- Acanthocephala anatomie a histologie klasifikace MeSH
- Bayesova věta MeSH
- Cyprinidae parazitologie MeSH
- fylogeneze * MeSH
- nemoci ryb parazitologie MeSH
- ribozomální DNA genetika MeSH
- RNA ribozomální 28S genetika MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Alžírsko MeSH
- Názvy látek
- ribozomální DNA MeSH
- RNA ribozomální 28S MeSH
PURPOSE: Despite the advances in nerve sparing and minimally invasive radical prostatectomy, erectile dysfunction remains an important adverse event after radical prostatectomy. Penile rehabilitation strategies have been developed to expedite and improve erectile function recovery. However, the differential efficacy and the best penile rehabilitation strategy are unclear as yet. We conducted a systematic review and network meta-analysis to investigate and compare the efficacy of different penile rehabilitation strategies. MATERIALS AND METHODS: A systematic search was performed in May 2020 using PubMed® and Web of Science™ databases according to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) extension statement for network meta-analysis. Studies that compared the erectile function recovery rate and adverse events between penile rehabilitation treatment groups (eg medications, devices and actions) and control group were included. We used the Bayesian approach in the network meta-analysis. RESULTS: A total of 22 studies (2,711 patients) met our eligibility criteria. Out of 16 different penile rehabilitation strategies and schedules vs placebo, only pelvic floor muscle training (OR 5.21, 95% CrI 1.24-29.8) and 100 mg sildenafil regular doses, ie once daily or nightly (OR 4.00, 95% CrI 1.40-13.4) were associated with a significantly higher likelihood of erectile function recovery. The certainty of results for 100 mg sildenafil regular dose was moderate, while pelvic floor muscle training had low certainty. The sensitivity analysis confirmed that the regular high dose of phosphodiesterase-5 inhibitors regardless of type vs placebo (OR 2.09, 95% CrI 1.06-4.17) was associated with a significantly higher likelihood of erectile function recovery with a moderate certainty. The on-demand doses of phosphodiesterase-5 inhibitors were not proven to be more beneficial than placebo. Secondary outcomes such as adverse events were not analyzed due to incomplete data in the literature. However, no serious adverse events were reported in any of the studies. CONCLUSIONS: Sildenafil 100 mg regular dose is the best penile rehabilitation strategy to improve erectile function recovery rates after radical prostatectomy. Although pelvic floor muscle training has been shown to be effective in increasing the erectile function recovery rate, well designed randomized controlled trials with larger sample sizes are needed to confirm the presented early results. The on-demand dose of phosphodiesterase-5 inhibitors should not be considered as a penile rehabilitation strategy.
- Klíčová slova
- erectile dysfunction, penis, prostatectomy, prostatic neoplasms, urogenital surgical procedures,
- MeSH
- Bayesova věta MeSH
- erektilní dysfunkce rehabilitace MeSH
- lidé MeSH
- obnova funkce MeSH
- pooperační komplikace rehabilitace MeSH
- prostatektomie metody MeSH
- randomizované kontrolované studie jako téma MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- síťová metaanalýza MeSH
- systematický přehled MeSH
The student population has been highly vulnerable to the risk of mental health deterioration during the coronavirus disease (COVID-19) pandemic. This study aimed to reveal the prevalence and predictors of mental health among students in Poland, Slovenia, Czechia, Ukraine, Russia, Germany, Turkey, Israel, and Colombia in a socioeconomic context during the COVID-19 pandemic. The study was conducted among 2349 students (69% women) from May-July 2020. Data were collected by means of the Generalized Anxiety Disorder (GAD-7), Patient Health Questionnaire (PHQ-8), Perceived Stress Scale (PSS-10), Gender Inequality Index (GII), Standard & Poor's Global Ratings, the Oxford COVID-19 Government Response Tracker (OxCGRT), and a sociodemographic survey. Descriptive statistics and Bayesian multilevel skew-normal regression analyses were conducted. The prevalence of high stress, depression, and generalized anxiety symptoms in the total sample was 61.30%, 40.3%, and 30%, respectively. The multilevel Bayesian model showed that female sex was a credible predictor of PSS-10, GAD-7, and PHQ-8 scores. In addition, place of residence (town) and educational level (first-cycle studies) were risk factors for the PHQ-8. This study showed that mental health issues are alarming in the student population. Regular psychological support should be provided to students by universities.
- MeSH
- Bayesova věta MeSH
- COVID-19 epidemiologie psychologie MeSH
- deprese epidemiologie psychologie MeSH
- duševní zdraví * MeSH
- lidé MeSH
- pandemie * MeSH
- prevalence MeSH
- psychický stres epidemiologie psychologie MeSH
- regresní analýza MeSH
- studenti psychologie MeSH
- univerzity * MeSH
- úzkostné poruchy epidemiologie psychologie MeSH
- víceúrovňová analýza MeSH
- zeměpis MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In this study, an artificial neural network (ANN) is used for the prediction of tensile strength of nano titanium dioxide (TiO2) coated cotton. The coating process was performed by ultraviolet (UV) radiations. Later on, a backpropagation ANN algorithm trained with Bayesian regularization was applied to predict the tensile strength. For a comparative study, ANN results were compared with traditional methods including multiple linear regression (MLR) and polynomial regression analysis (PRA). The input conditions for the experiment were dosage of TiO2, UV irradiation time and temperature of the system. Simulation results elucidated that ANN model provides high performance accuracy than MLR and PRA. In addition, statistical analysis was also performed to check the significance of this study. The results show a strong correlation between predicted and measured tensile strength of nano TiO2-coated cotton with small error values.
- Klíčová slova
- artificial neural network, tensile strength, titanium dioxide nanoparticles,
- Publikační typ
- časopisecké články MeSH
In this work, we present a novel methodology for performing the supervised classification of time-ordered noisy data; we call this methodology Entropic Sparse Probabilistic Approximation with Markov regularization (eSPA-Markov). It is an extension of entropic learning methodologies, allowing the simultaneous learning of segmentation patterns, entropy-optimal feature space discretizations, and Bayesian classification rules. We prove the conditions for the existence and uniqueness of the learning problem solution and propose a one-shot numerical learning algorithm that-in the leading order-scales linearly in dimension. We show how this technique can be used for the computationally scalable identification of persistent (metastable) regime affiliations and regime switches from high-dimensional non-stationary and noisy time series, i.e., when the size of the data statistics is small compared to their dimensionality and when the noise variance is larger than the variance in the signal. We demonstrate its performance on a set of toy learning problems, comparing eSPA-Markov to state-of-the-art techniques, including deep learning and random forests. We show how this technique can be used for the analysis of noisy time series from DNA and RNA Nanopore sequencing.
- Klíčová slova
- Markov processes, entropic AI, machine learning, small data, time series,
- Publikační typ
- časopisecké články MeSH
This paper represents the efficiency of machine learning tool, i.e., artificial neural network (ANN), for the prediction of functional properties of nano titanium dioxide coated cotton composites. A comparative analysis was performed between the predicted results of ANN, multiple linear regression (MLR) and experimental results. ANN was applied to map out the complex input-output conditions to predict the optimal results. A backpropagation ANN model called a multilayer perceptron (MLP), trained with Bayesian regularization were used in this study. The amount of chemicals and reaction time were selected as input variables and the amount of titanium dioxide coated on cotton, self-cleaning efficiency, antimicrobial efficiency and ultraviolet protection factor were analysed as output results. The accuracy of the proposed algorithm was evaluated and compared with MLR results. The obtained results reveal that MLP provides efficient results that are statistically significant in the prediction of functional properties ([Formula: see text]) compared to MLR. The correlation coefficient of MLP model ([Formula: see text]) indicates that there is a strong correlation between the measured and predicted functional properties with a trivial mean absolute error and root mean square errors values. MLP model is suitable for the functional properties and can be used for the investigation of other properties of nano coated fabrics.
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVES: In a separate document, we have provided specific guidance on performing individual pharmacokinetic (PK) studies using limited samples in persons with hemophilia with the goal to optimize prophylaxis with clotting factor concentrates. This paper, intended for clinicians, aims to describe how to interpret and apply PK properties obtained in persons with hemophilia. METHODS: The members of the Working Party on population PK (PopPK) of the ISTH SSC Subcommittee on Factor VIII and IX and rare bleeding disorders, together with additional hemophilia and PK experts, completed a survey and ranking exercise whereby key areas of interest in the field were identified. The group had regular web conferences to refine the manuscript's scope and structure, taking into account comments from the external feedback to the earlier document. RESULTS: Many clinical decisions in hemophilia are based on some form of explicit or implicit PK assessment. Individual patient PK profiles can be analyzed through traditional or PopPK methods, with the latter providing the advantage of fewer samples needing to be collected on any prophylaxis regimen, and without the need the for a washout period. The most useful presentation of PK results for clinical decision making are a curve of the factor activity level over time, the time to achieve a certain activity level, or related parameters like half-life or exposure (AUC). Software platforms have been developed to deliver this information to clinicians at the point of care. Key characteristics of studies measuring average PK parameters were reviewed, outlining what makes a credible head-to-head comparison among different concentrates. Large data collections of PK and treatment outcomes currently ongoing will advance care in the future. CONCLUSIONS: Traditionally used to compare different concentrates, PK can support tailoring of hemophilia treatment by individual profiling, which is greatly simplified by adopting a PopPK/Bayesian method and limited sampling protocol.
- Klíčová slova
- factor IX, factor VIII, population pharmacokinetics, tailored prophylaxis, tailoring,
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH