• MeSH
• audiovizuální záznam metody   přístrojové vybavení   MeSH
• financování organizované MeSH
• lidé MeSH
• měření pohybů očí přístrojové vybavení   MeSH
• počítačová grafika MeSH
• pohyby očí fyziologie   MeSH
• pupila fyziologie   MeSH
• uživatelské rozhraní počítače MeSH
• vestibulookulární reflex fyziologie   MeSH
• zobrazování trojrozměrné metody   MeSH
• Check Tag
• lidé MeSH

• MeSH
• lidé MeSH
• roztroušená skleróza diagnóza   MeSH
• Check Tag
• lidé MeSH

• MeSH
• běh MeSH
• diagnostické vybavení trendy   využití   MeSH
• elektrická impedance diagnostické užití   MeSH
• finanční podpora výzkumu jako téma MeSH
• funkční lateralita MeSH
• končetiny MeSH
• lehká atletika MeSH
• lidé MeSH
• přesuny tekutin MeSH
• složení těla MeSH
• tělesné tekutiny MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• srovnávací studie MeSH

For experiments with dispersed radioactive aerosols in a radon-aerosol chamber (RAC), it is desirable to know the activity of the radioactive aerosols applied in the RAC. A COLIBRI TTC survey metre with an SABG-15+ probe (Canberra, USA) was purchased for this purpose. The probe is designed for surface contamination measurements, and it is intended to measure the activity of aerosols deposited on the filters during experiments in the RAC. Since the probe is calibrated in a different geometry, its response in the authors' experimental geometry was simulated by a Monte Carlo method. The authors present a Monte Carlo model using MCNPX and an experimental verification of this probe model.

• MeSH
• aerosoly analýza   MeSH
• alfa částice MeSH
• design vybavení MeSH
• kalibrace MeSH
• metoda Monte Carlo MeSH
• monitorování radiace přístrojové vybavení   MeSH
• počítačová simulace MeSH
• radioaktivní látky znečišťující vzduch analýza   MeSH
• radiometrie přístrojové vybavení   metody   MeSH
• radionuklidy analýza   MeSH
• teoretické modely MeSH
• záření gama MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

This paper describes an ongoing project that has the aim to develop a low cost application to replace a computer mouse for people with physical impairment. The application is based on an eye tracking algorithm and assumes that the camera and the head position are fixed. Color tracking and template matching methods are used for pupil detection. Calibration is provided by neural networks as well as by parametric interpolation methods. Neural networks use back-propagation for learning and bipolar sigmoid function is chosen as the activation function. The user’s eye is scanned with a simple web camera with backlight compensation which is attached to a head fixation device. Neural networks significantly outperform parametric interpolation techniques: 1) the calibration procedure is faster as they require less calibration marks and 2) cursor control is more precise. The system in its current stage of development is able to distinguish regions at least on the level of desktop icons. The main limitation of the proposed method is the lack of head-pose invariance and its relative sensitivity to illumination (especially to incidental pupil reflections).

• MeSH
• fotografování metody   MeSH
• interpretace obrazu počítačem metody   MeSH
• lidé MeSH
• mladý dospělý MeSH
• neuronové sítě MeSH
• pohyby očí fyziologie   MeSH
• retina anatomie a histologie   fyziologie   MeSH
• retinoskopie metody   MeSH
• rozpoznávání automatizované metody   MeSH
• senzitivita a specificita MeSH
• uživatelské rozhraní počítače MeSH
• Check Tag
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• práce podpořená grantem MeSH

Objective.Electrical deep brain stimulation (DBS) is an established treatment for patients with drug-resistant epilepsy. Sleep disorders are common in people with epilepsy, and DBS may actually further disturb normal sleep patterns and sleep quality. Novel implantable devices capable of DBS and streaming of continuous intracranial electroencephalography (iEEG) signals enable detailed assessments of therapy efficacy and tracking of sleep related comorbidities. Here, we investigate the feasibility of automated sleep classification using continuous iEEG data recorded from Papez's circuit in four patients with drug resistant mesial temporal lobe epilepsy using an investigational implantable sensing and stimulation device with electrodes implanted in bilateral hippocampus (HPC) and anterior nucleus of thalamus (ANT).Approach.The iEEG recorded from HPC is used to classify sleep during concurrent DBS targeting ANT. Simultaneous polysomnography (PSG) and sensing from HPC were used to train, validate and test an automated classifier for a range of ANT DBS frequencies: no stimulation, 2 Hz, 7 Hz, and high frequency (>100 Hz).Main results.We show that it is possible to build a patient specific automated sleep staging classifier using power in band features extracted from one HPC iEEG sensing channel. The patient specific classifiers performed well under all thalamic DBS frequencies with an average F1-score 0.894, and provided viable classification into awake and major sleep categories, rapid eye movement (REM) and non-REM. We retrospectively analyzed classification performance with gold-standard PSG annotations, and then prospectively deployed the classifier on chronic continuous iEEG data spanning multiple months to characterize sleep patterns in ambulatory patients living in their home environment.Significance.The ability to continuously track behavioral state and fully characterize sleep should prove useful for optimizing DBS for epilepsy and associated sleep, cognitive and mood comorbidities.

• MeSH
• epilepsie komplikace   MeSH
• hipokampus MeSH
• hluboká mozková stimulace * metody   MeSH
• lidé MeSH
• mozek MeSH
• nuclei anteriores thalami * MeSH
• poruchy spánku a bdění * komplikace   diagnóza   terapie   MeSH
• retrospektivní studie MeSH
• thalamus MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

Solar radiation that reaches Earth's surface can have severe negative consequences for organisms. Both visible light and ultraviolet A (UVA) radiation are known to initiate the formation of reactive oxygen species (ROS) in human skin by photosensitization reactions (types I and II). In the present study, we investigated the role of visible light and UVA radiation in the generation of ROS on the dorsal and the palmar side of a hand. The ROS are known to oxidize biomolecules such as lipids, proteins, and nucleic acids to form electronically excited species, finally leading to ultraweak photon emission. We have employed a highly sensitive charge coupled device camera and a low-noise photomultiplier tube for detection of two-dimensional and one-dimensional ultraweak photon emission, respectively. Our experimental results show that oxidative stress is generated by the exposure of human skin to visible light and UVA radiation. The oxidative stress generated by UVA radiation is claimed to be significantly higher than that by visible light. Two-dimensional photon imaging can serve as a potential tool for monitoring the oxidative stress in the human skin induced by various stress factors irrespective of its physical or chemical nature.

• MeSH
• analýza selhání vybavení MeSH
• dávka záření MeSH
• design vybavení MeSH
• fotony MeSH
• kůže metabolismus   účinky záření   MeSH
• lidé MeSH
• radiometrie přístrojové vybavení   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• světlo MeSH
• ultrafialové záření MeSH
• vztah dávky záření a odpovědi MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Early implantable epilepsy therapy devices provided open-loop electrical stimulation without brain sensing, computing, or an interface for synchronized behavioural inputs from patients. Recent epilepsy stimulation devices provide brain sensing but have not yet developed analytics for accurately tracking and quantifying behaviour and seizures. Here we describe a distributed brain co-processor providing an intuitive bi-directional interface between patient, implanted neural stimulation and sensing device, and local and distributed computing resources. Automated analysis of continuous streaming electrophysiology is synchronized with patient reports using a handheld device and integrated with distributed cloud computing resources for quantifying seizures, interictal epileptiform spikes and patient symptoms during therapeutic electrical brain stimulation. The classification algorithms for interictal epileptiform spikes and seizures were developed and parameterized using long-term ambulatory data from nine humans and eight canines with epilepsy, and then implemented prospectively in out-of-sample testing in two pet canines and four humans with drug-resistant epilepsy living in their natural environments. Accurate seizure diaries are needed as the primary clinical outcome measure of epilepsy therapy and to guide brain-stimulation optimization. The brain co-processor system described here enables tracking interictal epileptiform spikes, seizures and correlation with patient behavioural reports. In the future, correlation of spikes and seizures with behaviour will allow more detailed investigation of the clinical impact of spikes and seizures on patients.

• Publikační typ
• časopisecké články MeSH

• MeSH
• chování zvířat MeSH
• mikropočítače MeSH
• periferní zařízení počítače MeSH
• pohyb MeSH
• ryby MeSH
• televize přístrojové vybavení   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH

Stereotaxe představuje aplikaci velmi vysokých dávek záření do nevelkých objemů v těle v několika málo frakcích se strmým úbytkem dávky do okolí. Preciznost zajišťuje přesná prostorová lokalizace objemu pomocí 3D zaměřovacího systému. Kybernetický nůž je neinvazívní alternativa chirurgického zákroku u některých zhoubných i nezhoubných ložisek v oblastech celého těla. Hlavní předností tohoto ozařovače je, že dokáže sledovat pozice nádoru během celé doby ozáření. Stereotaktickou radioterapií lze léčit maligní i benigní nádory, arteriovenózní malformace a rovněž některé funkční poruchy.

Stereotaxis refers to applying very high doses of radiation to locations of small volume in the body, in a couple of fractions, with a sharp cut-off of radiation dissipated into the surroundings. Precision is provided by accurate spatial location of the target area using a 3D targeting system. Cybernetic knife is a non-invasive alternative to surgery for certain both malignant and benign tumours in various areas of the body. The main advantage of this emitter is that it can track the location of the tumour during the whole time of irradiating it. Stereotactic radiotherapy can be used to treat both malignant and benign tumours, arteriovenous malformations and some functional disorders as well.

• MeSH
• intrakraniální arteriální nemoci radioterapie   MeSH
• komorová tachykardie radioterapie   MeSH
• lidé MeSH
• nádory jater radioterapie   sekundární   MeSH
• nádory mozku radioterapie   sekundární   terapie   MeSH
• nádory páteře radioterapie   MeSH
• nádory plic radioterapie   sekundární   MeSH
• nádory prostaty radioterapie   MeSH
• nemalobuněčný karcinom plic radioterapie   MeSH
• radiochirurgie * metody   trendy   využití   MeSH
• radioterapie s modulovanou intenzitou metody   využití   MeSH
• radioterapie * metody   trendy   využití   MeSH
• statistika jako téma MeSH
• stereotaktické techniky * přístrojové vybavení   trendy   využití   MeSH
• Check Tag
• lidé MeSH