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Our article profiles the evolution of a fully online writing course designed for adult learners in our university's Prior Learning Assessment Program. Based on our own observations and experiences teaching adult learners online, we question if the virtual learning environment presents different challenges and prospects for the adult learner versus the traditional student learner, along with an extension and complication of the more social metaphors of “virtual community.” Moreover, because of the changing demographic from traditional to adult students, we argue that this change also fosters a change in the relationship between teachers and students. In chronicling this relationship, we note problems when the labor of adult education becomes invisible to those supervising online instructors. Because of these “invisible” labor issues, we argue that successful online instruction must include a range of interactions between students and instructors that extend the more public concept of community to better acknowledge the importance of personal, private interaction. Thus, we conclude with a call to rethink our online writing pedagogies to be more flexible to adult learner needs and learning styles, simultaneously recognizing the impact of adult online education on faculty workload. 相似文献
74.
Here the authors evaluated the effect of the method of conditioning (bottle or intraoral [IO] infusion) on the strength of a flavor-drug association when measured in a standard 1-bottle consumption test or when measured by IO infusion in a taste reactivity test. When tested with the bottle test in Experiment 1, rats conditioned by bottle displayed stronger taste avoidance than those conditioned by IO infusion. When tested for rejection reactions with the taste reactivity test in Experiment 2, rats conditioned by infusion displayed a stronger aversion than did rats conditioned by bottle. The results suggest that when the contextual cues of conditioning are similar at conditioning and testing, a stronger association is evident regardless of the individual specifics of each method. These results may shed light on recent reports that different neural mechanisms are involved in conditioning by active consumption and passive infusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Bartholow Bruce D.; Dickter Cheryl L.; Sestir Marc A. 《Canadian Metallurgical Quarterly》2006,90(2):272
Two experiments tested the hypothesis that alcohol increases race-biased responding via impairment of self-regulatory cognitive control. Participants consumed either a placebo or alcohol and then made speeded responses to stereotypic trait words presented after White and Black face primes while behavioral and event-related brain potential (ERP) data were recorded. Alcohol did not affect stereotype activation in either experiment. Experiment 2 showed that alcohol significantly impaired the ability to inhibit race-biased responses but did not reliably influence control of counterstereotypic responses. This disinhibition appears driven by impairment of regulative cognitive control, as indexed by amplitude of the negative slow wave ERP component. These findings suggest that controlling racial bias can be a function of effective implementation of basic self-regulatory processes in addition to the motivational processes identified in other research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
This article presents a capability called Adaptive Decision-Making Frameworks (ADMF) and shows that it can result in significantly
improved system performance across run-time situation changes in a multi-agent system. Specifically, ADMF can result in improved
and more robust performance compared to the use of a single static decision-making framework (DMF). The ADMF capability allows
agents to dynamically adapt the DMF in which they participate to fit their run-time situation as it changes. A DMF identifies
a set of agents and specifies the distribution of decision-making control and the authority to assign subtasks among these
agents as they determine how a goal or set of goals should be achieved. The ADMF capability is a form of organizational adaptation
and differs from previous approaches to organizational adaptation and dynamic coordination in that it is the first to allow
dynamic and explicit manipulation of these DMF characteristics at run-time as variables controlling agent behavior. The approach
proposed for selecting DMFs at run-time parameterizes all domain-specific knowledge as characteristics of the agents’ situation,
so the approach is application-independent. The presented evaluation empirically shows that, for at least one multi-agent
system, there is no one best DMF for multiple agents across run-time situational changes. Next, it motivates the further exploration
of ADMF by showing that adapting DMFs to run-time variations in situation can result in improved overall system performance
compared to static or random DMFs. 相似文献
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Effects of activity-rest schedules on physiological strain and spinal load in hospital-based porters
Workers in physically demanding occupations require rest breaks to recover from physiological stress and biomechanical loading. Physiological stress can increase the risk of developing musculoskeletal disorders and repeated loading of the spine may increase the potential for incurring back pain. The aim of the study was to assess the impact of an altered activity-rest schedule on physiological and spinal loading in hospital-based porters. An existing 4-h activity-rest schedule was obtained from observations on eight male porters. This schedule formed the normal trial, which included two 5- and one 15-min breaks. An alternative 4-h schedule was proposed (experimental condition) that had two breaks each of 12.5 min. It was hypothesized that the experimental trial is more effective in promoting recovery from physiological strain and spinal shrinkage than the normal trial, due to the 5-min breaks being insufficient to allow physiological variables to return to resting levels or the intervertebral discs to reabsorb fluid. Ten males performed both test conditions and oxygen uptake VO2, heart rate, minute ventilation VE, perceived exertion and spinal shrinkage were recorded. There were no significant differences in any of the measured variables between the two trials (p > 0.05). Median heart rates were 78 (range 71-93) and 82 (71-90) beats.min(-1) for the normal trial and the experimental trial respectively, indicating that the activity was of low intensity. The light intensity was corroborated by the oxygen uptakes (0.75, range 0.65-0.94 1.min(-1)). Spinal shrinkage occurred to the same extent in the two trials (2.12 +/- 3.16 mm and 2.88 +/- 2.92 mm in the normal trial and the experimental trial respectively). Varying the length and positioning of the rest breaks did not significantly affect the physiological responses or magnitude of spinal shrinkage between the two trials. More physically demanding work than the porters' schedule should induce greater physiological fatigue and spinal shrinkage. The ratio between activity and rest breaks would then become more important. 相似文献
79.
Kathryn I Pollak Cheryl A Oncken Isaac M Lipkus Bercedis L Peterson Geeta K Swamy Pamela K Pletsch Pauline Lyna Rebecca J Namenek Brouwer Laura J Fish Evan R Myers 《Nicotine & tobacco research》2006,8(4):547-554
Improvements in smoking cessation interventions for pregnant smokers are needed. One major step is to examine the potential effectiveness of nicotine replacement therapy (NRT). The potential benefits of providing pregnant women with NRT to help them quit smoking are still unknown; early interventions to test the effectiveness and efficacy are vital to advancing the field. This paper describes recruitment efforts for a multiclinic trial to test the effectiveness of NRT use in addition to behavioral therapy in promoting cessation during pregnancy. The biggest challenge is recruiting sufficient numbers of pregnant women. This paper discusses specific obstacles for recruitment and solutions. Knowing the potential pitfalls to recruiting pregnant women into these trials can lead to better studies and thus improved outcomes. 相似文献
80.
Burke C. Fujiwara M. Yamaguchi M. Nishimoto H. Honmou H. 《Lightwave Technology, Journal of》1992,10(5):610-615
The possibility of a 128-line photonic space division switching system incorporating LiNbO3 switch matrices and semiconductor traveling wave amplifiers (TWAs) is discussed. System design is considered in terms of the most suitable location for the TWA devices that gives the most practical power margin. Design requirements for a 128-line photonic switching system suitable for a small-sized private branch exchange requirement are presented along with experimental results. It has been shown that a five-stage switch cascade, suitable for such a high-capacity switching system with a power margin of greater than 5 dB in the highest switch loss situation is possible, using low-facet-reflection TWAs. Such TWA devices have been developed in the 1.3-μm wavelength region with maximum fiber-to-fiber gain values of 15 dB. With maximum gain-polarization dependencies of 3 dB, switch losses can be compensated even under TM mode operation 相似文献