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J C Rupp

Publications and source records attributed to J C Rupp.

12 recordsLinked to original sources
PubMed1999

Impact of geographical origin on mating behaviour in two species of Biomphalaria (Planorbidae: Gastropoda).

Studies of inbreeding and outcrossing have traditionally concentrated on matings within populations. The influence of geographical origin on mate choice in animals from different populations has received less attention. We investigated whether planorbid snails mated preferentially within their own population or with snails from other populations. Snails from three Biomphalaria pfeifferi strains and three B. glabrata strains were allowed to mate with conspecifics in the laboratory. We recorded their matings at night using time-lapse video. When they could choose between sympatric and allopatric snails, Biomphalaria snails significantly preferred the former: snails of each population mated more often with sympatric than with allopatric snails. This tendency to avoid outcrossing may indicate that, in some species, local adaptations can be more valuable than genetic novelties. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1997

Gender and the effect of gonadal hormones on the progression of inherited polycystic kidney disease in rats.

Human autosomal dominant polycystic kidney disease (ADPKD) is a common inherited disease and displays a gender dimorphism in renal disease progression. Han:SPRD-Cy rats manifest a form of ADPKD that is similar in many respects to that seen in humans. In Han:SPRD rats, male Cy/+ rats have more prominent renal changes and develop renal failure at an early age, whereas female Cy/+ rats exhibit less severe renal cystic change and have normal renal function until advanced age. To determine whether the male gonadal hormone, testosterone, contributes to this gender dimorphism, males were sham operated or castrated; some castrated rats were repleted with 5alpha-dihydrotestosterone. Female rats were sham operated or ovariectomized before sham operation or testosterone treatment. All treatments started at 4 weeks of age and ended at 10 weeks of age. Renal enlargement, cystic change, and renal function were assessed. In the males, castration reduced renal enlargement and cystic change; testosterone treatment abrogated these effects. Neither of these manipulations affected azotemia in male Cy/+ rats. In the females, testosterone was renotropic for both normal and cystic kidneys. In the Cy/+ females, testosterone treatment caused azotemia and an increase in the severity of the PKD. Ovariectomy blunted the effect of testosterone on cystic kidney enlargement. Testosterone treatment did not completely erase the gender-associated differences in azotemia in the Cy/+ rat. These data confirm the renotropic effects of testosterone and indicate that testosterone influences the progression of renal cystic change in male and female rats with ADPKD.

Animals↗
PubMed1995

The new science and the public sphere in the premodern era.

This paper argues that the New Science, which was seen as essentially a public enterprise, was moreover a major constituent of the public sphere in early modern era. In seventeenth- and eighteenth-century Western Europe the sphere of public experimentation, testing, and discussion related to the new science, manifested itself as a highly diversified, contested, and complex social field. Two general problems arose in constructing this cultural public sphere: the selection of participants in the debate and the inclusion of a heterogenous public in the experimental scene. National authorities employed diverse policies but none denied the necessity of public debate for testing the validity of experimentations. The public sphere had to create its own conditions of existence by imposing manifold regulations in order to make these public meetings possible and enjoyable. The regulations emphasized common interest and the moral code as the most basic condition for the sustenance of the public sphere, thus enhancing self-restraint, tolerance, and politeness on the part of both discussants and participants. The more inclusive and heterogenous the public sphere, the more these norms were required. Thus the sphere of public debate constituted by early modern science implied a civilizing process, quite different from and more encompassing than the one analyzed by Norbert Elias.

Europe↗
PubMed1991

Peak heart rates during maximal running and swimming: implications for exercise prescription.

Thirty-four college-age fitness swimmers, 19 males and 15 females, were maximally tested during treadmill running (TR) and tethered swimming (TS). A discontinuous, graded test protocol was used for both TR and TS with 2-min stages and 1-min rest periods. Peak HRs were obtained via a UNIQ CIC monitor during the last 120 s of each stage. Blood lactate was measured at 3 min post exercise using a YSI Model 27 Analyzer. TS peak HR was significantly lower (p less than 0.05) than both the age-predicted HRmax (220-age) and TR peak HR by 13 and 11 bt.min-1, respectively. Blood lactate for TS (8.0 mmol.l-1) and TR (8.1 mmol.l-1) were similar. Mean target heart rate range (THRR) calculated from TS peak HR (144-176 bt.min-1) was significantly lower than THRR calculated from age-predicted max HR (151-187 bt.min-1) and TR peak HR (151-186 bt.min-1). For young adult fitness swimmers, we suggest reducing the HRmax obtained from treadmill exercise or predicted from age by 12 bt.min-1. This correction appears to be a reasonable estimate of swimming HRmax that can be used for calculating exercise intensity.

Adolescent↗
PubMed1973

The love bug.

Explore the source record for details and available documents.

Adult↗
PubMedDate not supplied

Training level comparison study. Effect of high and low intensity exercise on ventilatory threshold in men with coronary artery disease.

PURPOSE: To determine whether exercise at low intensity (LO; 50% of peak VO2) or high intensity (HI; 85% of peak VO2) results in improvement of the ventilatory threshold (VT), 186 men with coronary artery disease (CAD) were enrolled in an exercise study for 1 year. METHODS: A symptom-limited exercise test was performed at baseline and the heart rate corresponding to 50% and 85% of peak VO2 was determined. Subjects were randomized to LO or HI intensity exercise. Exercise sessions included 45 minutes of walking/jogging and/or stationary cycling at the appropriate target heart rate and were conducted 3 days per week. The exercise test was repeated at 3 and 6 months. Target heart rates were revised to adjust for training. RESULTS: Both LO and HI resulted in improved VO2 at VT and peak. However, HI resulted in greater improvement than LO. CONCLUSION: Among this population, both HI and LO improve the VO2 at VT and peak, but the improvement is greater with HI. The VT can be a useful adjunct to heart rate and peak oxygen uptake when prescribing exercise.

Anaerobic Threshold↗