Search results for "Dynamic"
showing 10 items of 12329 documents
Correlation of cerebral blood flow and MCA flow velocity measured in healthy volunteers during acetazolamide and CO2 stimulation
1995
Abstract The assessment of the cerebrovascular reserve capacity (RC) has become a widely used tool in the management of cerebrovascular disease. Discrepancies become obvious, however, if results obtained with different methods are compared. Aim of the present study, therefore, was to compare blood velocity and cerebral perfusion data in the same group of healthy test persons. In 32 volunteers regional cerebral blood flow (rCBF) was measured with the 133 Xe-inhalation method. F1 as grey matter flow and the initial slope index (ISI) were computed. Simultaneously flow velocity in the middle cerebral artery (V MCA ) was assessed by transcranial Doppler sonography (TCD). Measurements were perfor…
The Effects of Isoflurane and Desflurane on Intracranial Pressure, Cerebral Perfusion Pressure, and Cerebral Arteriovenous Oxygen Content Difference …
2003
Background Desflurane is a volatile anesthetic agent with low solubility whose use in neurosurgery has been debated because of its effect on intracranial pressure and cerebral blood flow. The purpose of this study was to determine the variations on intracranial pressure (ICP) and cerebral perfusion pressure (CPP) as well as on cerebral arteriovenous oxygen content difference (AVDo(2)) in normocapnic patients scheduled to undergo removal of supratentorial brain tumors with no evidence of mass effect during anesthesia with isoflurane or desflurane. Methods In 60 patients scheduled to undergo craniotomy and removal of supratentorial brain tumors with no evidence of midline shift, anesthesia w…
Music Listening and Stress in Daily Life—a Matter of Timing
2017
Purpose Despite increasing evidence suggesting that music listening in daily life has stress-reducing effects, studies mostly rely on subjective, retrospective data on music listening. Thus, the temporal dynamics underlying the stress-reducing effect of music listening remain unclear. Therefore, we aimed to examine the temporal dynamics of the associations between stress and music listening by assessing subjective and objective data on music in daily life. Design An exploratory Ambulatory Assessment study examining a total of 60 participants (37 women), aged 18 to 34 years (M = 22.4 years, SD = 3.5) was conducted. Methods For 1 week, participants answered questions on music listening and st…
Validation of the Dutch Eating Behavior Questionnaire (DEBQ) in a sample of Spanish women
2014
Contains fulltext : 124145.pdf (Publisher’s version ) (Closed access) The Dutch Eating Behavior Questionnaire (DEBQ) was developed to measure eating styles that may contribute to or attenuate the development of overweight. It comprises three scales that measure emotional, external and restrained eating. The main goal of this study is to evaluate the internal structure of the Spanish version of the DEBQ using updated psychometric techniques in a sample of women. A sample of 647 Spanish females answered the questionnaire. Both exploratory structural equation modeling and confirmatory factor analysis were used to evaluate the factor structure of the DEBQ. Reliabilities were estimated with Cron…
Examining patients' and other group members' agreement about their alliance to the group as a whole and changes in patient symptoms using response su…
2012
There is a lack of research examining patients' and other group members' agreement about their therapeutic alliance. In the present study, the person-group (P-G) fit model was adopted to predict that the group member symptom reduction will be greater when the group member's and the other group members' perceptions of their alliance to the group-as-a-whole fit and are high. In addition, the effect of disagreement between the group member and the other group members in their perceptions of the group alliance on the individual's outcome was investigated by using response surface analysis. Thirty-two patients from 5 long-term (> 1 year) psychodynamic group treatments were studied. Participants …
Cerebral blood flow velocities after subarachnoid haemorrhage in relation to the amount of blood clots in the initial computed tomography.
1998
In 72 patients with acute subarachnoid haemorrhage (SAH) the relationship between the amount of subarachnoid blood clots detected by initial cranial computed tomography (CCT) up to 48 hours after bleeding and the later development of vasospasm, established by blood flow velocity measurement with transcranial Doppler ultrasound (TCD) was investigated. The serial Doppler examinations started within the first 72 hours after SAH and were carried out every second day up to three weeks. Each Doppler recording was accompanied by a neurological examination. Patients classified as Hunt and Hess grade V were excluded from the study. All patients with remarkable brain oedema in CCT or with intracrania…
Mentally represented motor actions in normal agingII. The influence of the gravito-inertial context on the duration of overt and covert arm movements
2007
Here, we address the question of whether normal aging influences action representation by comparing the ability of 14 young (age: 23.6 +/- 2.1 years) and 14 older (age: 70.1 +/- 4.5 years) adults to mentally simulate arm movements under a varying dynamic context. We conducted two experiments in which we experimentally manipulated the gravity and inertial components of arm dynamics: (i) unloaded and loaded vertical arm movements, rotation around the shoulder joint, (ii) unloaded and loaded horizontal arm movements, rotations around the shoulder and elbow joints, in two directions (inertial anisotropy phenomenon). The main findings indicated that imagery ability was equivalent between the two…
Biomechanical implications of excessive endograft protrusion into the aortic arch after thoracic endovascular repair
2015
Endografts placed in the aorta for thoracic endovascular aortic repair (TEVAR) may determine malappositioning to the lesser curvature of the aortic wall, thus resulting in a devastating complication known as endograft collapse. This premature device failure commonly occurs in young individuals after TEVAR for traumatic aortic injuries as a result of applications outside the physical conditions for which the endograft was designed. In this study, an experimentally-calibrated fluid-structure interaction (FSI) model was developed to assess the hemodynamic and stress/strain distributions acting on the excessive protrusion extension (PE) of endografts deployed in four young patients underwent TE…
Mitral and aortic regurgitation in 84 patients with mucopolysaccharidoses
1995
In echocardiographic and necropsy studies nodular thickening of the mitral valve and, less frequently, of the aortic valve has been found in 60%-90% of patients with mucopolysaccharidoses (MPS). Little is known about the haemodynamic consequences of these morphological changes. In this study 84 unselected patients with different enzymatically proven MPS and 84 age and sex matched, healthy persons were studied prospectively by colour Doppler flow mapping. The patients' age ranged from 1 to 47 years (median 8.1 years). Mitral and aortic regurgitation were defined as a holosystolic or holodiastolic jet originating from the valve into the left atrium or the left ventricular outflow tract, respe…
The Effect of Adaptive Nonlinear Frequency Compression on Phoneme Perception
2017
Purpose This study implemented a fitting method, developed for use with frequency lowering hearing aids, across multiple testing sites, participants, and hearing aid conditions to evaluate speech perception with a novel type of frequency lowering. Method A total of 8 participants, including children and young adults, participated in real-world hearing aid trials. A blinded crossover design, including posttrial withdrawal testing, was used to assess aided phoneme perception. The hearing aid conditions included adaptive nonlinear frequency compression (NFC), static NFC, and conventional processing. Results Enabling either adaptive NFC or static NFC improved group-level detection and recognit…