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G M Harris

Publications and source records attributed to G M Harris.

6 recordsLinked to original sources
PubMed2001

The computational performance of a high-order coupled FEM/BEM procedure in electropotential problems.

This paper presents a thorough analysis of the computational performance of a coupled cubic Hermite boundary element/finite element procedure. This C1 (i.e., value and derivative continous) method has been developed specifically for electropotential problems, and has been previously applied to torso and skull problems. Here, the behavior of this new procedure is quantified by solving a number of dipole in spheres problems. A detailed set of results generated with a wide range of the various input parameters (such as dipole orientation, location, conductivity, and solution method used in each spherical shell [either finite element or boundary elements]) is presented. The new cubic Hermite boundary element procedure shows significantly better accuracy and convergence properties and a significant reduction in CPU time than a traditional boundary element procedure which uses linear or constant elements. Results using the high-order method are also compared with other computational methods which have had quantitative results published for electropotential problems. In all cases, the high-order method offered a significant improvement in computational efficiency by increasing the solution accuracy for the same, or fewer, solution degrees of freedom.

Biomedical Engineering↗
PubMed1999

Decreased plasma tissue factor pathway inhibitor in women taking combined oral contraceptives.

Use of combined oral contraceptives (OC) is associated with a significant risk of thrombosis. The mechanisms of this effect are not clearly defined. Tissue factor pathway inhibitor (TFPI) is a circulating anti-coagulant that inhibits the earliest steps in activation of the extrinsic coagulation pathway. It plays a central role in control of coagulation but its contribution to the thrombotic risk associated with OC has not been assessed. Plasma TFPI antigen and activity, factor VIIa, prothrombin fragments 1&2, von Willebrand antigen, fibrinogen, and low density lipoprotein cholesterol were measured by standard assays in women taking OC (aged 16 to 45 years, n = 40) and age-matched women not taking OC (controls, n = 40). Plasma TFPI antigen did not vary significantly across the menstrual cycle in controls. Women on OC had a 25% reduction in plasma TFPI antigen (median 51.0 ng/ml; 95% confidence intervals [CI] 37.5 to 85.5; control 68.0 ng/ml, CI 61.0 to 95.0; P < 0.001) and a 29% reduction in TFPI activity (78.5 U/ml, CI 57.5 to 107.5; control 111.0 U/ml, CI 79.5 to 171.0; P < 0.001) compared to controls. Plasma factor VIIa activity and prothrombin fragments 1&2 were also significantly increased in women using OC (both P < 0.001), indicating activation of the extrinsic coagulation pathway. These results demonstrate that normal cyclic variations in estrogen and/or progesterone do not significantly alter plasma TFPI levels. However, estrogens and/or progestogens in OC result in activation of the extrinsic coagulation pathway and significantly reduce plasma TFPI, its major circulating inhibitor. Reduced plasma TFPI levels may underlie the thrombotic effects of OC.

Adolescent↗
PubMed1993

Hypnosis for child sexual abuse: a case study.

In this case study, hypnosis incorporating images of competence and efficacy was utilized to assist a young woman to overcome feelings of powerlessness that were engendered by childhood sexual abuse. This treatment was highly effective in assisting this patient to resolve her traumatic memories of these episodes of molestation and abuse.

Adaptation, Psychological↗
PubMed1991

Hypnotherapy for agoraphobia: a case study.

In this case study, hypnosis combined with progressive relaxation effectively eliminated the cause of panic attacks in a 34 year old female. After an initial period of progressive relaxation, this patient was trained in desensitization techniques and in hypnosis. The introduction of hypnosis provided this young woman with long term relief from her symptoms of agoraphobia and panic. This study provides further evidence for the efficacy of hypnosis in the elimination of panic attacks.

Adult↗
PubMedDate not supplied

Nosocomial postoperative tetanus infection.

In light of the fact that tetanus spores are present throughout the environment, this article presents a case of nosocomial postoperative tetanus. A review of the immunization schedule is included to familiarize the surgeon with the active and passive methods of immunization. The authors recognize that tetanus infections are uncommon in our society, but all doctors should become aware of the appropriate treatment program as presented in this article.

Anti-Bacterial Agents↗