Crosswalk time estimation and time perception: an experimental study among older female pedestrians.

Since the sense of time is strongly influenced by advancing age, this laboratory study aimed to find out more about older pedestrians' decisions to cross the road, focusing on their estimates of how long it would take them to cross. The walking times of older female adults with or without any walking impairment and of healthy young adults were recorded on a walkway representing a road section. Participants also performed actual and imagined crossings of this "road" as well as a duration production task. Results showed that misestimated crossing times were related to the individual time base, with stronger time distortions in some older participants. A comparison between the older participants with disabilities and their age-paired counterparts without disabilities revealed an overestimation of crossing time in the former, affording them a bigger safety margin.

Stability and phase locking in human soccer juggling.

We explored a variant of juggling in which human adults were asked to rhythmically bounce a soccer ball with their dominant foot while standing on the other foot. Eight subjects performed the task at three prescribed heights and one free height condition. Kinematic analyses of foot movement at ball-foot impact showed that, for the smallest height, foot acceleration was positive or zero at impact, which indicates an active stabilization regime. Increasing juggling height resulted in foot acceleration becoming increasingly negative at impact, which is required for a passive dynamical stability regime. These results show that skilled soccer jugglers exploit the passive stability regime afforded by the task, but that similar stability can be achieved with an active stabilization strategy.

The regulation of release parameters in underarm precision throwing.

The aim of this study was to determine if adults spontaneously exploit the laws of physics to achieve better accuracy when throwing at various distances. Eight adults performed 25 underarm throws at five horizontal circular targets located 4, 5, 6, 7 and 8 m away with a constant 5% relative accuracy requirement. Angle and speed of the ball at release were found to increase with throwing distance, while the coordinates of the release point did not change significantly. These results support the idea that people minimize the variability in impact distance by adapting both the angle and the speed at ball release following a mechanical optimum predicted by the laws of physics. Moreover, variability in distance was found to be less than expected because of independent variations in the angle and speed at ball release. Hence, the control of precision throwing seems to imply compensatory variability, as frequently reported in the control of skilled actions.

[Ambulatory laser and turbinectomy in the treatment of nasal obstruction. Apropos of 68 cases]. / Analyse du laser ambulatoire et de la turbinectomie dans le traitement de l'obstruction nasale. A propos de 68 cas.

The purpose of this prospective study was to compare subjectively and objectively the efficiency of laser vaporisation against surgical procedure in treatment of nasal obstruction related to vasomotor rhinitis. 40 inferior nasal turbinates laser vaporisations were compared to 28 surgical inferior turbinectomies. This trial was based on rhinomanometric data before and after laser or surgical management and on appreciation of individual nasal comfort. The results obtained with conventional surgery were slightly better than laser vaporisation; however this new procedure succeed in 75% of cases with a mean of one year follow-up. The rhinomanometric++ findings appeared especially contributing when significant disorders exist before treatment.

[Bilateral nephrocarcinomas in the adult. Bibliographical and statistical analysis. On the basis of 2 personal cases and 106 cases in the literature (author's transl)]. / Les néphroépithéliomes bilatéraux de l'adulte. Approche bibliographique et statistique. A propos de 2 cas personnels et 106 cas de la littérature.

On the basis of two personal cases, the authors undertook an overall study of 108 cases published between 1909 and 1978. First personal case: 2 successive tumours at an interval of 5 years. Total nephrectomy of the 2nd carcinoma resulted in survival for 6 years with hemodialysis. The patient is living, with metastases. Second case: 2 simultaneous carcinomas with adrenal metastases with death following unilateral partial nephrectomy. An exhaustive review of the literature revealed the following interesting statistical factors: 1.8 p. 100 of carcinomas of the kidney are bilateral. Amongst the 108 cases studied, 51 were simultaneous and 57 successive. Treatment becomes appropriately more and more audacious: total nephrectomy on one side and partial on another, double partial nephrectomy, performance "ex vivo" of partial excisions, bilateral total nephrectomy followed by hemodialysis or transplantation. These tumours affect young individuals: mean age 51 years and male in 7 cases out of 10. Mean survival of all cases combined was 18 months, but subtracting operative mortality this increased to 22 months. Mean survival was greater in successive carcinomas, in individuals aged over 55 years (26 months) than in simultaneous carcinomas of the younger age group (13 months). Overall prognosis has improved for simultaneous carcinomas (mean survival 2.5 months for the period 1909--1954 increasing to 25 months for the period 1972--1978); whilst it has remained stable (mean survival 21 months) for successive carcinomas. The mean interval between 2 successive carcinomas was 6 years and 6 months with a range of 5 months for 20 years. Prognosis was based on numerous factors, but in particular treatment. When surgery was incomplete or absent, mean survival was 5 1/2 months (40 cases), the figure reaching 26 months for the 52 cases in whom an adequate excision was performed (of the order of 30 months for the period 1972--1978). No published case should be reported before a minimum survival of 2 years.