[Purpose] The purpose of this study was to investigate the influence of sacral sitting in a wheelchair on contact pressure on the buttocks and back, and shear force on the ischial region. [Subjects and Methods] Twenty-six healthy adults assumed two postures while seated in a wheelchair: a basic sitting posture, and sacral sitting with the pelvis tilted posteriorly and the ischium slid forward b...

This paper is concerned with the frictionless unilateral contact problem (i.e., a Signorini problem with the elasticity operator). We consider a mixed finite element method in which the unknowns are the displacement field and the contact pressure. The particularity of the method is that it furnishes a normal displacement field and a contact pressure satisfying the sign conditions of the continu...

This paper describes the relationship between the rates of charge transport (by tunneling) across self-assembled monolayers (SAMs) in a metal/SAM//Ga2O3/EGaIn junction and the geometric contact area (Ag) between the conical Ga2O3/ EGaIn top-electrode and the bottom-electrode. Measurements of current density, J(V), across SAMs of decanethiolate on silver demonstrate that J(V) increases with Ag w...

Corneas of 28 human subjects were exposed to oxygen partial pressures, in a gas goggle, of either 6.9, 17.1, or 22.2 mm Hg, and the corneal swelling was measured by pachometry for 4 hr. Following an initial rise, the swelling stabilized after about 3 hr; in many subjects it was reversed, indicating an adaptation process. The average corneal swelling after 4 hr for the three oxygen partial press...

PURPOSE To evaluate the levels of dinucleotides diadenosine tetraphosphate (Ap(4)A) and diadenosine pentaphosphate (Ap(5)A) in tears of patients wearing rigid gas permeable (RGP) contact lenses on a daily wear basis and of patients wearing reverse-geometry RGP lenses overnight for orthokeratology treatment. METHODS Twenty-two young volunteers (10 females, 12 males; 23.47 ± 4.49 years) were fi...

The clinical and haemodynamic significance of the subaortic pressure gradient in patients with muscular (hypertrophic) subaortic stenosis (hypertrophic obstructive cardiomyopathy) has long been debated. In this report we summarize the evidence which indicates that true obstruction to left ventricular outflow exists in these patients. Rapid left ventricular ejection, through an outflow tract nar...

Wheel wear has been a concern in the railway for several decades. Studying the form change of the wheel/rail contacts in particular railways consisting of sharp curves helps to identify the risk of severe or catastrophic wear to minimize maintenance costs in order to be competitive in the transportation business. In this paper, the wheel/rail contact was studied on the particular railways. The ...

Pressure measurements were made at four sites on the right foot of six normal subjects while they walked in a standard shoe, conventional padded cast, total contact cast, and again in a shoe. No differences in mean relative pressure were found between the padded cast and the total-contact cast. Significant reductions in mean relative pressure were found between the standard shoe and walking cas...

PURPOSE To investigate if the accuracy of intraocular pressure (IOP) measurements using rebound tonometry over disposable hydrogel (etafilcon A) contact lenses (CL) is affected by the positive power of the CLs. METHODS The experimental group comprised 26 subjects, (8 male, 18 female). IOP measurements were undertaken on the subjects' right eyes in random order using a Rebound Tonometer (ICare...

Estimation of the hip joint contact area and pressure distribution during activities of daily living is important in predicting joint degeneration mechanism, prosthetic implant wear, providing biomechanical rationales for preoperative planning and postoperative rehabilitation. These biomechanical data were estimated utilizing a generic hip model, the Discrete Element Analysis technique, and the...