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271.
P. A. Hancock M. Vercruyssen G. J. Rodenburg 《Current psychology (New Brunswick, N.J.)》1992,11(3):203-225
Two experiments are reported which investigated how subject gender and time-of-day influenced the estimation of duration and
the perception of task-related mental workload. In the first experiment, 24 subjects performed a filled time-estimation task
in a constant blacked-out, noise-reduced environment at 0800h, 1200h, 1600h, and 2000h, respectively. In the second experiment,
12 different subjects performed an unfilled time estimation task in similar conditions at 0900h, 1400h, and 1900h. At the
termination of all experimental sessions, participants completed the NASA Task Load Index workload assessment questionnaire
as a measure of perceived mental workload. Results indicated that physiological response, reflected in body temperature change,
followed an expected pattern of sequential increase with time-of-day. However, estimates of duration and the perception of
mental workload showed no significant effects for time-of-day. In each of the experiments there were significant differences
in time estimation and mental workload response contingent on the gender of the participant. These results are interpreted
in light of the previous positive findings for circadian fluctuation in performance efficiency and the equivocal findings
of a gender difference in time estimation. A unifying account of these collective results is given based on gender by time-of-day
interactional effects.
An earlier version of this paper was presented at the 32nd Annual Meeting of the Human Factors Society, Anaheim, CA, October,
1988. 相似文献
272.
Meisel A 《Kennedy Institute of Ethics journal》1992,2(4):309-345
The legal consensus that has evolved through adjudication and legislation since the Karen Quinlan case in 1976 is founded on the premise that there is a bright line between passive euthanasia and active euthanasia. Indeed, the term passive euthanasia is often eschewed in favor of less emotionally-laden terminology such as "forgoing life-sustaining treatment" or "terminating life support" so as to further sever any possible connection with active euthanasia. Legal approval has been bestowed upon passive euthanasia under certain circumstances while active euthanasia is routinely condemned. This consensus was put to a test in 1990 when the United States Supreme Court ruled on the Cruzan case. However, the Court's narrow decision did not upset the consensus, and in the most significant appellate decisions handed down by state courts since Cruzan, there has been a reaffirmation--and possibly even an extension--of the consensus. Two other threats to the legal consensus about forgoing life-sustaining treatment have begun to manifest themselves: the increasing pressure for mercy killing and "futility" cases. Both of these challenge the fundamental premises on which the consensus is grounded. 相似文献
273.
We assessed the effects of a computerized matching-to-sample procedure on the spelling performances of three students with mental retardation. Initially, the students could 1) match pictures and printed words to one another, and 2) match pictures and printed words to spoken words. However, they could not construct words to either pictures or spoken words (e.g., touch, in order, the letters s->h->o->e given the spoken-word sample Shoe). Word constructions then improved markedly after exposure to delayed constructed-response identity matching (e.g., touch the letters s->h->o->e given the printed-word sample shoe). One subject's oral and written spelling also improved. The results extend previous research by showing multiple positive effects of a computerized spelling intervention. These effects may have occurred in part because of the formation of stimulus classes among pictures, printed words, and spoken words. 相似文献
274.
Virginia A. Sharpe 《Theoretical medicine and bioethics》1992,13(4):295-318
Carol Gilligan has identified two orientations to moral understanding; the dominant ‘justice orientation’ and the under-valued ‘care orientation’. Based on her discernment of a ‘voice of care’, Gilligan challenges the adequacy of a deontological liberal framework for moral development and moral theory. This paper examines how the orientations of justice and care are played out in medical ethical theory. Specifically, I question whether the medical moral domain is adequately described by the norms of impartiality, universality, and equality that characterize the liberal ideal. My analysis of justice-oriented medical ethics, focuses on the libertarian theory of H.T. Engelhardt and the contractarian theory of R.M. Veatch. I suggest that in the work of E.D. Pellegrino and D.C. Thomasma we find not only a more authentic representation of medical morality but also a project that is compatible with the care orientation's emphasis on human need and responsiveness to particular others. 相似文献
275.
Instruction in baby massage and the Burleigh Relaxation Bath technique was given to one-half of our sample of 32 couples who had just had their first child. This brief intervention, given at 4 weeks post-partum, led to beneficial behavioural and psychological effects for the family system when assessed at 12 weeks postpartum. Depression and marital satisfaction were assessed with mothers and fathers at 4 weeks and 12 weeks after the birth of their child, and self-esteem was measured at 12 weeks only. The mothers and fathers who were shown baby bathing and massage techniques showed higher degrees of marital satisfaction and self-esteem, as well as lower levels of depression at 12 weeks post-partum, than parents who did not receive instruction. It seems likely that brief interventions which educate new parents concerning functional techniques of baby care may favourably affect their feelings of competence and be of benefit to the entire family system. 相似文献
276.
GINA CHRISTINE KEMP BRIAN A. GLASER RICHARD PAGE ARTHUR M. HORNE 《Journal of Addictions & Offender Counseling》1992,12(2):34-46
The authors explored the relationship between family support and adjustment for adult men in a detention center, as measured by a staff rating scale completed by the appropriate counselor. 相似文献
277.
A tether system has been developed for continuous monitoring of blood pressure in the micropig. The micropig is a suitable model for blood-pressure research because of the similarity of its cardiovascular system to that of humans and because of its sensitivity to high sodium intake. The system consists of a metal boom, attached via a universal joint to a wall 6 ft above floor level, that extends horizontally to the center of the enclosure. A fluid and electronic swivel affixed to the boom is connected to a flexible, hollow, metal tether that descends to a vest worn by the micropig. The vest contains a pressure transducer to which an indwelling arterial catheter is connected via a stopcock. The transducer cable and an infusion line ascend through the interior of the tether to the swivel. The system remains in equilibrium through a system of pulleys and counterweights. Continuous, 24-h recording shows a diurnal variation characterized by higher heart rate but lower blood pressure during the day than at night. The system has been found to be effective for continuous studies over intervals of a month or more. 相似文献
278.
Much of what we learn from an experiment depends on what we ask of the subjects and how we ask it. Most music perception and cognition research is implemented using a single methodology. Recently, questions have been raised about the validity and generalizability of such a limited approach, particularly regarding such complicated theoretical constructs as musical tonality. We propose that a useful technique is to converge on the answer to experimental questions by applying multiple methods, in essence, simultaneously investigating the central research question as well as ancillary questions of method. Such an approach is facilitated by a computer hardware and software system that integrates experimental design, data collection, data analysis, and data dissemination, linking off-the-shelf components through standard file formats and data-exchange protocols. The list-based system, using an IBM-type PC running Windows 3.0, handles real-time natural sound sampling and playback, signal synthesis and analysis, MIDI input and output, digitized picture display, and various subject-response mechanisms. On the basis of graphical icons, the integrated system can be used to build custom experimental designs. Examples of convergent psychomusical experiments that were designed, implemented, and analyzed using the system are discussed. 相似文献
279.
Data often contain periodic components plus random variability. Walsh analysis reveals periodicities by fitting rectangular functions to data. It is analogous to Fourier analysis, which represents data as sine and cosine functions. For many behavioral measures, Fourier transforms can produce spurious peaks in power spectra and fail to resolve separable components. Walsh analysis is superior for strongly discontinuous data. The strengths and weaknesses of each transform are discussed, and specific algorithms are given for the newer Walsh technique. 相似文献
280.
Variation of amplitude envelope at stimulus onset has been considered to be of primary importance for distinguishing voiceless affricates from fricatives (e.g., |t∫| and |∫|). In earlier perceptual experiments, however, variation in amplitude rise time was confounded with variation in frication duration. In two experiments, these variables were independently manipulated, and their individual and combined effects for perception of |t∫| and |∫| were examined. Variation in amplitude rise time alone was not sufficient to signal the voiceless affricate/fricative contrast in these experiments, but variation in frication duration alone was sufficient. 相似文献