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When gestational diabetes is diagnosed, the physician has an opportunity to help the patient deliver a healthy baby by encouraging optimal glycemic control. In this article, the authors describe risk factors, methods of diagnosis, and a plan of management that includes a nutritional program based on ADA guidelines, use of insulin if needed, home monitoring of glucose levels, and appropriate exercise.

1. We studied the influences of phase of respiration and breathing frequency upon human sinus node responses to arterial baroreceptor stimulation. 2. Carotid baroreceptors were stimulated with brief (0.6 sec), moderate (30 mmHg) neck suction during early, mid, and late inspiration or expiratin at usual breathing rates, or, during early inspiration and expiration at breathing rates of 3, 6, 12, and 24 breaths/min. 3. Baroreceptor stimuli applied during early and mid inspiration and late expiration provoked only minor sinus node inhibition; stimuli begun during late inspiration and early expiration provoked maximum sinus node inhibition. 4. At breathing rates of 3, 6 and 12 breaths/min, expiratory baroreflex responses were significantly greater than inspiratory responses; at 24 breaths/min, however, inspiratory and expiratory baroreceptor stimuli produced comparable degrees of sinus node inhibition. 5. Our results delineate an important central biological rhythm in normal man: human baroreflex responsiveness oscillates continuously during normal, quiet respiration. The phase shift of baroreflex responsiveness on respiration suggests that this interaction cannot be ascribed simply to gating synchronous with central inspiratory neurone activity. Regularization of heart rate during rapid breathing is associated with loss of the differential inspiratory-expiratory baroreflex responsiveness which is present at usual breathing rates.

A finite element approach is used to predict stress and deformation states of uterine muscle tissue under plane strain indentation by a flexible shield. Realistic, one-dimensional "punch" elements at the shield edges assure that muscle shear stresses remain bounded within experimentally measured values. For typical tissue, bearing pressure, deformation flow fields and edge slip stresses leading to tissue damage are calculated. Penetration depth to shield width ratios are up to 3.0. A piecewise linear, elastic approximation to the highly variable, nonlinear mechanical behavior of the tissue is used. Results are applied to the prediction of possible tissue damage by a flexible shield intrauterine contraceptive device, in place and in equilibrium with typical multiparous uteri.

A SERIES OF MATHEMATICAL MODELS OF THE INTERACTION BETWEEN AN OCCUPANT AND THE INTERIOR OF A VEHICLE IS PRESENTED. THE FOLLOWING PARAMETER STUDIES USING AN EIGHT-MASS, TWO-DIMENSIONAL MODEL ARE DISCUSSED; BELT MATERIAL PROPERTIES, BELT SLACK, BELT GEOMETRIC CONFIGURATION, AND COMPARISON OF SEATS WITH AND WITHOUT HEADRESTS IN REAR IMPACT. IN ADDITION, IT IS DEMONSTRATED BY EXAMPLE THAT SIMPLE MATHEMATICAL MODELS CAN PERFORM A VALUABLE SERVICE IN LAYING THE GROUNDWORK FOR MORE SOPHISTICATED ANALYTICAL AND EXPERIMENTAL WORK AS WELL AS YIELDING SHORT TERM RESULTS. FINALLY, THREE-DIMENSIONAL MODELS ARE DISCUSSED. IT IS SHOWN THAT A THREE-MASS, THREE-DIMENSIONAL MODEL IS A LOGICAL EXTENSION OF CURRENT SIMULATION EFFORTS IN ORDER TO PROVIDE INSIGHT INTO OCCUPANT RESPONSE IN OBLIQUE AND LATERAL IMPACT AS WELL AS NONSYMMETRIC RESTRAINT SYSTEM. /AUTHOR/

One of the primary difficulties in providing adequate simulation of human response during a crash has been the lack of data describing human response under similar circumstances. Because of the medical care problems which may arise from volunteer tests, the bulk of the testing has been performed under the sponsorship of governmental agencies who can provide a proper medical staffing and hospital care facilities should they become necessary.

In the study of the effect of impact on the human body at injury-producing levels it has been necessary to use models because of the danger of severe and serious damage to living volunteers. Since accurate information regarding the response of the human body to injury-producing impacts is negligible, it is apparent that available anthropometric dummies are of no value in such investigations. Because of the very significant differences between impact responses in animals and in humans it is difficult to justify the extrapolation of responses in impact experiments with live animals to similar responses in humans. This leaves the human cadaver as the only reasonably good model available for such experimental work, results of which can only be evaluated in terms of the behavior of the skeletal system. But even with this list of available results, embalming and the presence of dead tissue instead of living tissue would be expected to have some effect on the response obtained to a specific impact.