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1.
Rev Sci Instrum ; 83(10): 10D511, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23130790

RESUMO

A new endoscope with optimised divertor view has been developed in order to survey and monitor the emission of specific impurities such as tungsten and the remaining carbon as well as beryllium in the tungsten divertor of JET after the implementation of the ITER-like wall in 2011. The endoscope is a prototype for testing an ITER relevant design concept based on reflective optics only. It may be subject to high neutron fluxes as expected in ITER. The operating wavelength range, from 390 nm to 2500 nm, allows the measurements of the emission of all expected impurities (W I, Be II, C I, C II, C III) with high optical transmittance (≥ 30% in the designed wavelength range) as well as high spatial resolution that is ≤ 2 mm at the object plane and ≤ 3 mm for the full depth of field (± 0.7 m). The new optical design includes options for in situ calibration of the endoscope transmittance during the experimental campaign, which allows the continuous tracing of possible transmittance degradation with time due to impurity deposition and erosion by fast neutral particles. In parallel to the new optical design, a new type of possibly ITER relevant shutter system based on pneumatic techniques has been developed and integrated into the endoscope head. The endoscope is equipped with four digital CCD cameras, each combined with two filter wheels for narrow band interference and neutral density filters. Additionally, two protection cameras in the λ > 0.95 µm range have been integrated in the optical design for the real time wall protection during the plasma operation of JET.

3.
Biomed Tech (Berl) ; 49(5): 125-31, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15212197

RESUMO

The computer-aided detection of artefacts became an essential task with increasing automation of quantitative electroencephalogram (EEG) analysis during anaesthesiological applications. The different algorithms published so far required individual manual adjustment or have been based on limited decision criteria. In this study, we developed an artificial neural networks-(ANN-)aided method for automated detection of artefacts and EEG suppression periods. 72 hr EEG recorded before, during and after anaesthesia with propofol have been evaluated. Selected parameterized patterns of 0.25 s length were used to train the ANN (22 input, 8 hidden and 4 output neurons) with error back propagation. The detection performance of the ANN-aided method was tested with processing epochs between 1 to10 s. Related to examiner EEG evaluation, the average detection performance of the method was 72% sensitivity and 80% specificity for artefacts and 90% sensitivity and 92% specificity for EEG suppression. The improvement in signal-to-noise ratio with automated artefact processing was 1.39 times for the spectral edge frequency 95 (SEF95) and 1.89 times for the approximate entropy (ApEn). We conclude that ANN-aided preprocessing provide an useful tool for automated EEG evaluation in anaesthesiological applications.


Assuntos
Algoritmos , Anestesia/métodos , Diagnóstico por Computador/métodos , Eletroencefalografia/efeitos dos fármacos , Eletroencefalografia/métodos , Redes Neurais de Computação , Propofol/administração & dosagem , Anestésicos Intravenosos/administração & dosagem , Artefatos , Inteligência Artificial , Infusões Intravenosas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
Surg Radiol Anat ; 22(5-6): 255-60, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11236319

RESUMO

The aim of the study was to evaluate the occurrence of the anatomical variations of the musculotendinous junction of the flexor carpi ulnaris (FCU) muscle and the variations of its insertion onto the pisiform. One hundred cadaver specimens preserved according to Thiel's method were assessed. Following careful dissection, the distance between the musculotendinous junction and the pisiform and the width of the muscle belly were determined. Three typical anatomical variations were found: 1) a large muscle belly running distally almost to the insertion onto the pisiform; 2) the muscle belly ending more proximally, with some large fibres running parallel to the tendon and almost reaching the pisiform; 3) the musculotendinous junction ending more proximally, with only single fibres continuing distally. The length of the tendon was greater than 10 mm. A number of variations of the distal region of FCU were observed. The presence of muscle fibres almost reaching the insertion point onto the pisiform have to be considered when interpreting MRI or ultrasound findings of this region.


Assuntos
Músculo Esquelético/anatomia & histologia , Punho/anatomia & histologia , Idoso , Cadáver , Feminino , Humanos , Masculino , Tendões/anatomia & histologia , Ulna
5.
Psychiatry Res ; 85(2): 199-207, 1999 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-10220010

RESUMO

Clinical evidence indicates that parasympatholytic effects of tricyclic antidepressants increase with age. The aim of the present study was to determine the possible physiological reason for this phenomenon. Subjects included 23 patients (14 female) with major depression, melancholic type, and 23 age- and sex-matched healthy control subjects. Cardiac vagal tone was measured at rest using both spectral analysis and a time domain beat-to-beat method. Results of the spectral and time domain methods for the estimation of vagal tone used in this study were highly correlated in control subjects as well as in medicated depressed subjects. Both patients and control subjects showed an age-related decline in cardiac vagal tone. Tricyclic antidepressants decreased vagal tone significantly by 25-49% depending on age (20-60 years), although the age difference was not significant. The greater effect of tricyclic antidepressants on parasympathetic activity typically seen in older age groups may reflect the fact that predrug levels of vagal tone are already low in older patients. Measurement of vagal tone prior to drug administration may therefore be of prognostic value for anticholinergic side effects.


Assuntos
Envelhecimento/fisiologia , Amitriptilina/farmacologia , Antidepressivos Tricíclicos/farmacologia , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/fisiopatologia , Adulto , Amitriptilina/uso terapêutico , Antidepressivos Tricíclicos/uso terapêutico , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Sistema Nervoso Parassimpático/efeitos dos fármacos , Sistema Nervoso Parassimpático/fisiopatologia , Análise de Regressão , Nervo Vago/efeitos dos fármacos , Nervo Vago/fisiopatologia
6.
Biol Psychiatry ; 42(10): 914-9, 1997 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9359977

RESUMO

We investigated autonomic control of heart rate in patients with major depression, melancholic type. Twenty-three depressed inpatients who were being treated with tricyclic antidepressants and 23 depressed patients who were taking no medications were compared with age- and sex-matched control groups on resting cardiac vagal tone and heart rate. In unmedicated depressed patients, cardiac vagal tone was comparable to that of control subjects, but heart rate was significantly higher. This increase in heart rate may have been due to sympathetic activation caused by anxiety, since the depressed patients were significantly more anxious than the control subjects. Medicated patients exhibited diminished cardiac vagal tone and higher heart rate than unmedicated patients and controls. This was probably due to the anticholinergic effects of the antidepressants. Our findings suggest that cardiac vagal tone is not lower than normal in patients with depression, melancholic type.


Assuntos
Antidepressivos Tricíclicos/farmacologia , Antidepressivos Tricíclicos/uso terapêutico , Sistema Nervoso Autônomo/efeitos dos fármacos , Transtorno Depressivo/tratamento farmacológico , Frequência Cardíaca/efeitos dos fármacos , Adulto , Arritmias Cardíacas/diagnóstico , Transtorno Depressivo/psicologia , Eletrocardiografia , Feminino , Humanos , Pessoa de Meia-Idade , Nervo Vago/efeitos dos fármacos
7.
Forensic Sci Int ; 82(2): 121-7, 1996 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-8885372

RESUMO

The effects of long-term imprisonment on cognitive functions are investigated in a longitudinal study. Twenty-four serious offenders in an Austrian penitentiary underwent concentration and memory performance measurements via a questionnaire presented to them under controlled conditions in two sessions at a 42 month interval. The difference in the parameters indicated cognitive impairment after this period that was highly significant (P < 0.01); this can be interpreted as a direct consequence of imprisonment.


Assuntos
Transtornos Cognitivos/etiologia , Prisioneiros/psicologia , Adulto , Áustria , Homicídio , Humanos , Inteligência , Masculino , Pessoa de Meia-Idade , Personalidade , Testes Psicológicos , Fatores de Tempo
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