In this paper, the application of D-optimal models, as an alternative to response surface models (RS models) for design of experiment (DOE) was examined. Two D-optimal models for tilt-rotors in the wind tunnel experiment, as a form of quadratic functions, were generated based on a chosen optimality criterion. This optimality criterion was used to generate the optimized sampled points in the des...

Respiratory physiological deadspace may increase from 35 per cent of the tidal volume in the normal anaesthetized, normotensive and supine patient to as much as 80 per cent in the hypotensive patient in the head-up tilt. Increased mean airway pressure, hypotension, sudden head-up tilt or maintenance of tilt, all tend to increase the respiratory deadspace. Arterial and end-tidal Pco3 differences...

BACKGROUND AND PURPOSE We sought to determine whether the introduction of EEG monitoring during head-up tilt testing could significantly improve the understanding of the cerebral events occurring during tilt-induced vasovagal syncope and the potential danger to the patient of this diagnostic procedure. METHODS EEG monitoring was performed during head-up tilt testing in a group of 63 consecuti...

OBJECTIVE Panoramic radiographs are routinely used to assess the mesiodistal axial inclination of teeth (MDAI) in orthodontic treatment. These radiographs are sensitive to minor deviations from standard head position that result in image distortions. The aim of this study is to measure and quantify the changes in MDAI on panoramic radiograph resulting from changes in patient head position. MA...

PURPOSE While an ideal vestibulo-ocular reflex (VOR) generates ocular rotations compensatory for head motion, during visually guided movements, Listing's Law (LL) constrains the eye to rotational axes lying in Listing's Plane (LP). The present study was conducted to explore the recent proposal that the VOR's rotational axis is not collinear with the head's, but rather follows a time-dependent s...

PURPOSE Pregnancy is characterized by many musculoskeletal changes that affect daily living activities and walking. The purpose of this study was to examine the effect of pregnancy on pelvic and trunk kinematics, and their relationship during the three pregnancy trimesters. METHODS Three-dimensional pelvis and trunk motions were measured using Qualisys Gait Analysis System in the first, secon...

Two symbolic indexes, the percentage of sequences characterized by three heart periods with no significant variations (0V%) and that with two significant unlike variations (2UV%), have been found to reflect changes in sympathetic and vagal modulations, respectively. We tested the hypothesis that symbolic indexes may track the gradual shift of the cardiac autonomic modulation during an increment...

INTRODUCTION AND OBJECTIVES The magnitude of the change in heart rate during the first few minutes of the head-up tilt test has been used to predict the test's result. The aim of this study was to investigate whether the heart rate increase during the head-up tilt test potentiated with nitroglycerin is related to the development of syncope. PATIENTS AND METHOD The study included 158 consecuti...

The purpose of this study was to correlate the trochlear shape and patellar tilt angle and lateral patellar displacement at rest and maximal voluntary isometric contraction (MVIC) exercises during open (OKC) and closed kinetic chain (CKC) in subjects with and without anterior knee pain. Subjects were all women, 20 who were clinically healthy and 19 diagnosed with anterior knee pain. All subject...