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1.
The cadence that maximises power output developed at the crank by an individual cyclist is conventionally determined using a laboratory test. The purpose of this study was two-fold: (i) to show that such a cadence, which we call the optimal cadence, can be determined using power output, heart-rate, and cadence measured in the field and (ii) to describe methodology to do so. For an individual cyclist's sessions, power output is related to cadence and the elicited heart-rate using a non-linear regression model. Optimal cadences are found for two riders (83 and 70 revolutions per minute, respectively); these cadences are similar to the riders’ preferred cadences (82–92?rpm and 65–75?rpm). Power output reduces by approximately 6% for cadences 20?rpm above or below optimum. Our methodology can be used by a rider to determine an optimal cadence without laboratory testing intervention: the rider will need to collect power output, heart-rate, and cadence measurements from training and racing sessions over an extended period (>6 months); ride at a range of cadences within those sessions; and calculate his/her optimal cadence using the methodology described or a software tool that implements it.  相似文献   
2.
Roger Cousinet     
Louis Raillon 《Prospects》1993,23(1-2):221-233
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4.
Adults are typically required to make values‐based decisions multiple times each day.Why, then, should a discussion of values not be explicit across the college curriculum and intentionally integrated into the cocurriculum? The authors describe a place where the work of values education is widely shared.  相似文献   
5.
Two experiments attempted to establish vicious-circle behavior through fear motivation combined with secondary punishment. In Experiment 1, rats were trained with two CSs, a tone and a buzzer, paired with shock in different contexts. Secondary punishment based on delay and trace conditioning procedures facilitated running in fear-motivated rats, relative to four control groups. In Experiment 2, rats were given pairings of a tone CS with shock, and a buzzer CS with a drop into a water tank. Fear-motivated rats which received secondary punishment during either 33% or 100% of test trials exhibited self-punitive running relative to a nonpunished (0%) group and a backward-conditioning control group. Results indicate that “all secondary” vicious-circle behavior can be established through Pavlovian conditioning, thus supporting a conditioned fear interpretation.  相似文献   
6.
In line with other research, Udell, Dorey, and Wynne’s (in press) finding that dogs and wolves pass on some trials of a putative theory-of-mind test and fail on others is as informative about the methods and concepts of the research as about the subjects. This commentary expands on these points. The intertrial differences in the target article demonstrate how critical the choice of cues is in experimental design; the intersubject-group differences demonstrate how life histories can interact with experimental design. Even the best-designed theory-of-mind tests have intractable logical problems. Finally, these and previous research results call for the introduction of an intermediate stage of ability, a rudimentary theory of mind, to describe subjects’ performance.  相似文献   
7.
Interference in auditory short-term memory in the bottlenosed dolphin,Tursiops truncatus (Montagu), was studied using a delayed matching-to-sample task. At each trial, one of two sample sounds, chosen randomly, was projected underwater for 4 sec and then, after a variable delay interval, both sounds were presented. A response to the sound matching the initial sample was reinforced. Correct matching was significantly reduced following short intervals between trials in combination with long delays after the sample (proactive interference), or when a near continuous irrelevant sound was inserted into the delay interval (retroactive interference). There was rapid habituation to interference if the irrelevant sound was short in duration relative to the delay interval. For both proactive and retroactive interference, the errors were predominantly responses to the sample sound appropriate to the prior trial rather than to the current trial, indicating that memory for the relative recency of events (temporal memory) was degraded by interference. When interference was deleted or minimized, temporal memory remained nearly perfect over 30-sec delay intervals, the longest tested. The importance of distinguishing between temporal memory and nontemporal, or event, memory in different forms of the delayed matching task was emphasized.  相似文献   
8.
This study examined the effects of a newly developed on-site consultancy programme to improve global quality of the child care environment in non-parental child care centres for 0- to 4-year-old children as measured with the ITERS-R/ECERS-R. Using a randomised controlled trial with a pretest, posttest, and follow-up test, we compared 35 experimental group with 33 control group. The consultancy programme comprised three consultations in total. Analysis on the items that were specifically targeted during the consultancy showed a significant improvement on these targeted items between pretest and posttest and between posttest and follow-up. The effect of the consultancy programme on the total scores (including the non-targeted items) was not significant.  相似文献   
9.
The effects of method of reproduction, status of researcher, and personalization of signature on the initial rate of return of mail questionnaires were investigated, using a one-page combination cover letter and questionnaire mailed to 600 professors at the University of Maryland, College Park. The levels of each experimental variable were: Status — professor, graduate student; signature — hand signed in ink, mimeographed facsimile; reproduction — typed, photocopied, mimeographed.A response rate of 69% was obtained without using any follow-up procedures. Chi square analyses indicated no significant differences in the rate of returns for the levels of any of the experimental variables.It appears that initial return rate will not be significantly affected by using the most efficient, least expensive method available.  相似文献   
10.
Leon IG 《Child development》2002,73(2):652-663
The American definition of kinship based on biological ties, the practice of closed adoption, and stigmas associated with adoption may decisively influence adoption-related losses. Cross-cultural and historical accounts of adoption that do not apply to these contemporary American constructs of parenthood and practices of adoption suggest outcomes that are not as integrally based on loss. Adoption in infancy is defined as parenting a child with one set of (adoptive) parents and two (adoptive and birth) families. Implications for adoption research, policy, and practice are discussed.  相似文献   
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