- MeSH
- Fourierova analýza MeSH
- hlas fyziologie MeSH
- lidé MeSH
- počítačové zpracování signálu MeSH
- Check Tag
- lidé MeSH
Respiratory sinus arrhythmia (RSA) is an index of cardiovagal regulation, emotional and cognitive processing. RSA is quantified using heart rate variability (HRV) spectral analysis at respiratory-linked high-frequency band (HF-HRV) using Fast Fourier transformation (FFT) or autoregressive (AR) method, both requiring resampling of recordings - a potential source of error. We hypothesized that rarely used HRV time-frequency analysis with Lomb-Scargle periodogram (LSP) without resampling could be more sensitive to detect neurocardiac response to posture change than FFT and AR. Orthostasis (posture change from supine to standing) evoked significant decrease of HF-HRV well detectable by FFT, AR, and LSP. In contrast, during posture change from sitting to lying, significant increase of HF-HRV and peak HF was best detected using LSP. In regression analysis, the associations between RR-interval, HF-HRV, and peak HF were best detected when evaluated using LSP. Time-frequency HRV analysis with LSP could represent an important alternative to conventional FFT and AR methods for assessment of cardiovagal regulation indexed by RSA.
- MeSH
- časové faktory MeSH
- dechová frekvence fyziologie MeSH
- elektrokardiografie MeSH
- Fourierova analýza MeSH
- lidé MeSH
- mladiství MeSH
- neparametrická statistika MeSH
- regresní analýza MeSH
- respirační sinusová arytmie fyziologie MeSH
- srdeční frekvence fyziologie MeSH
- Check Tag
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Arterial physiology relies on a delicate three-dimensional (3D) organization of cells and extracellular matrix, which is remarkably altered by vascular diseases like abdominal aortic aneurysms (AAA). The ability to explore the micro-histology of the aorta wall is important in the study of vascular pathologies and in the development of vascular constitutive models, i.e., mathematical descriptions of biomechanical properties of the wall. The present study reports and validates a fast image processing sequence capable of quantifying collagen fiber organization from histological stains. Powering and re-normalizing the histogram of the classical fast Fourier transformation (FFT) is a key step in the proposed analysis sequence. This modification introduces a powering parameter w, which was calibrated to best fit the reference data obtained using classical FFT and polarized light microscopy (PLM) of stained histological slices of AAA wall samples. The values of w = 3 and 7 give the best correlation (Pearson's correlation coefficient larger than 0.7, R 2 about 0.7) with the classical FFT approach and PLM measurements. A fast and operator independent method to identify collagen organization in the arterial wall was developed and validated. This overcomes severe limitations of currently applied methods like PLM to identify collagen organization in the arterial wall.
- MeSH
- aneurysma břišní aorty patologie MeSH
- aorta chemie MeSH
- Fourierova analýza MeSH
- histocytochemie metody MeSH
- kolagen analýza MeSH
- laboratorní automatizace metody MeSH
- počítačové zpracování obrazu metody MeSH
- polarizační mikroskopie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
) .608 -- 12.3 FFT of Real Functions 617 -- 12.4 Fast Sine and Cosine Transforms 620 -- 12.5 FFT in Two Spectral Applications 640 -- 13.0 Introduction .640 -- 13.1 Convolution and Deconvolution Using the FFT 641 -- 13.2 Correlation and Autocorrelation Using the FFT 648 -- 13.3 Optimal (Wiener) Filtering with the FFT 649 -- 13.4 Power Spectrum Estimation Using the FFT 652 -- 13.5 Digital Filtering in the Time 13.8 Spectral Analysis of Unevenly Sampled Data .685 -- 13.9 Computing Fourier Integrals Using the FFT
3rd ed. xxi, 1235 s. : il. ; 27 cm + 1 CD-ROM
- MeSH
- matematické výpočty počítačové MeSH
- matematika MeSH
- numerická analýza pomocí počítače * MeSH
- Publikační typ
- monografie MeSH
AIMS: To analyze the event-related desynchronization/synchronization (ERD/ERS) attended with the mental load arising while solving two cognitive tasks. The features of the presented visual stimulus determined the type of cognitive task that should be solved. METHODS: For each experimental task and everybody's subject FFT Analysis module calculated the total power histograms from a fixed frequency band (3-20 Hz or 8-13 Hz) for each 3-second EEG sample with 50 % overlay and all electrodes. From the histograms the software derived two FFT single values--the average Total Power (TP) and Frequency at Maximum Power (FMP). RESULTS: It has been shown that during the solution of cognitive tasks the marked changes of ongoing EEG activity appeared. The short lasting and localized amplitude decrease in rhythmic activity (ERD) and the change of EEG frequency were among the most frequent. The ERD extent was determined by an informational content of processed visual stimuli and by the site of scalp-recording electrode. A higher mental load related to the solution of cognitive tasks shifted the average FM to lower frequencies. CONCLUSION: The suitability of an analysis of ongoing EEG activity to uncover differences in people's brain activation patterns when engaged in performing cognitively demanding tasks was proved.
51 -- 7.1 Psychoterapeutické přístupy .53 -- 7.2 Léčba zaměřená na rodinu (family-focused therapy - FFT
75 s. ; 18 cm
- MeSH
- bipolární porucha farmakoterapie terapie diagnóza MeSH
- kognitivně behaviorální terapie MeSH
- psychoterapie MeSH
- Konspekt
- Psychiatrie
- NLK Obory
- psychiatrie
Schnellreaktionsmethode nach Santo .68 -- vin -- Inhaltsverzeichnis -- Seite -- c) Der Fleckfieber-Folien-Test (FFT
viii, 88 stran, 4 strany obrazové přílohy : ilustrace ; 22 cm
- MeSH
- sérologické testy MeSH
- Publikační typ
- monografie MeSH
- Konspekt
- Mikrobiologie
- NLK Obory
- diagnostika
- biochemie
- alergologie a imunologie
