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With the increase in the use of games for education and training, learning game developers seek to create games that not only teach, but engage and motivate learners.
One attribute often associated with successful and motivating games or training devices is authenticity, also referred to as realism or fidelity. Many falsely equate the amount of realism within a training environment to effective training; the higher the realism, the more effective the training. However, as in other training methodologies, a combination of factors, such as learner expertise, instructional domain, and details related to the knowledge and skills taught, informs the optimal level of authenticity within an effective learning game.
This chapter defines and describes authenticity as the combination of physical and cognitive fidelity. We discuss these concepts and summarize cognitive research related to authenticity and effective learning. Finally, we discuss the decisions a learning game developer makes during different stages of the development process to achieve the optimal blend of authenticity, and ultimately an effective, motivating learning game.
DNA transposases are enzymes that catalyze the movement of discrete pieces of DNA from one location in the genome to another. Transposition occurs through a series of controlled DNA strand cleavage and subsequent integration reactions that are carried out by nucleoprotein complexes known as transpososomes. Transpososomes are dynamic assemblies which must undergo conformational changes that control DNA breaks and ensure that, once started, the transposition reaction goes to completion. They provide a precise architecture within which the chemical reactions involved in transposon movement occur, but adopt different conformational states as transposition progresses. Their components also vary as they must, at some stage, include target DNA and sometimes even host-encoded proteins. A very limited number of transpososome states have been crystallographically captured, and here we provide an overview of the various structures determined to date. These structures include examples of DNA transposases that catalyze transposition by a cut-and-paste mechanism using an RNaseH-like nuclease catalytic domain, those that transpose using only single-stranded DNA substrates and targets, and the retroviral integrases that carry out an integration reaction very similar to DNA transposition. Given that there are a number of common functional requirements for transposition, it is remarkable how these are satisfied by complex assemblies that are so architecturally different.
Somewhere very near the top of psychology's list of most vexing and least settled matters are the nagging questions of how and when young persons come to anything like a “mature” account (or folk conception) of the nature and limitations of human knowing. That is, we (where “we” refers to all of us salaried professionals actually paid to know about such things) seem unable to agree about almost anything having to do with people's changing beliefs about belief (Chandler et al., 2002; Chandler and Sokol, 1999). Do young persons ordinarily abandon some entry-level commitment to “naive realism” at the age of four, or is it fourteen, or twenty-four (Chandler and Carpendale, 1998)? Are our earliest insights about the inherently agentic (and therefore ineluctably subjectivized or relativized) nature of human knowing standardly acquired during the preschool or, rather, the post-graduate years (Chandler et al., 2000)? When, give or take a few decades, is it fair to say that young persons will have already acquired a journeyman's “theory-of-mind,” adult-like in all of its basic particulars (Chandler, 2001)? Is it four, or eight, or twelve, and, if not, do such accomplishments await some “age of majority,” or the acquisition of a liberal arts degree (Kitchener and King, 1981)? No fair-minded reader of the contemporary research literature on personal epistemologies could, we maintain, come away from an exhaustive review of the several hundred studies given over to such matters with anything like a confident conclusion (Chandler et al., 2002).
Molecular dynamics simulations are performed to model milling via a focused ion beam (FIB). The goal of this investigation is to examine the fundamental dynamics associated with the use of FIBs, as well as the phenomena that govern the early stages of trench formation during the milling process. Using a gallium beam to bombard a silicon surface, the extent of lateral damage (atomic displacement) caused by the beam at incident energies of both 2 and 30 keV is examined. These simulations indicate that the lateral damage is several times larger than the beam itself and that the mechanism responsible for the formation of a V-shaped trench is due to both the removal of surface material, and the lateral and horizontal migration of subsurface silicon atoms toward the vacuum/crater interface. The results presented here provide complementary information to experimental images of trenches created during milling with FIBs.
The origin of maize has been a topic of interest to both biologists and archaeologists. During the twentieth century, the view point that maize is a domesticated form of teosinte received convincing support from biological data and is now broadly accepted among biologists familiar with the issues and data. There is no support of any kind for an alternative view that maize is a hybrid of the grasses Zea diploperennis and Tripsacum.
Research was conducted to formulate a seedling johnsongrass emergence model as influenced by temperature and burial depth using the poikilotherm rate equation. A series of constant-temperature growth chamber experiments with johnsongrass seed buried at various depths in fritted clay was conducted to develop a temperature/burial emergence database. The poikilotherm rate equation was fit to the emergence data from burial depths of 0 to 2.5 cm at constant temperatures between 20 and 44 C. These data were then combined to formulate a single poikilotherm rate equation to model the emergence of seedling johnsongrass from 0 and 2.5 cm deep and 20 to 44 C. This combined model was validated against two independent emergence data sets with good results.
The present study examined neuropsychological (NP) functioning and associated medical, neurological, brain magnetic resonance imaging (MRI), and psychiatric findings in 389 nondemented males infected with Human Immunodeficiency Virus-Type 1 (HIV-1), and in 111 uninfected controls. Using a comprehensive NP test battery, we found increased rates of impairment at each successive stage of HIV infection. HIV-related NP impairment was generally mild, especially in the medically asymptomatic stage of infection, and most often affected attention, speed of information processing, and learning efficiency; this pattern is consistent with earliest involvement of subcortical or frontostriatal brain systems. NP impairment could not be explained on the bases of mood disturbance, recreational drug or alcohol use, or constitutional symptoms; by contrast, impairment in HIV-infected subjects was related to central brain atrophy on MRI, as well as to evidence of cellular immune activation and neurological abnormalities linked to the central nervous system. (JINS, 1995, 1, 231–251.)
The doubly-labelled water (2H218O) technique was used to assess the long-term rates of energy expenditure and, after accounting for any changes in body composition, the derived rates of energy intake in weight-stable ‘large-eating’ (n 6) and ‘small-eating’ (n 6) women. The self-reported energy intakes (approximately 11.2 v. 5.6 MJ/d) and energy expenditures (approximately 8.5 v. 12.4 MJ/d) for the ‘large-eating’ and ‘small-eating’ groups respectively, should not be sustainable without significant body-weight changes. 2H218O-assessed rates of energy expenditure for the ‘large-eaters’ (approximately 8.5 MJ/d) and ‘small-eaters’ (approximately 11.3 MJ/d) were in close agreement with the results obtained using 5 d, self-reported activity diaries but the derived rates of energy intake for the ‘large-’ (approximately 8.5 MJ/d) and ‘small-eaters’ (approximately 10.8 MJ/d) were markedly different from those obtained using self-reported, weighed food diaries. When two ‘small-eaters’ were supplied with their self-reported energy intakes (approximately 5 MJ/d) for up to 28 d both subjects lost about 0.75 kg body-weight/week. These results provide no support for the existence of ‘metabolically efficient’ women in the community.
Rates of energy expenditure (J/kg fat-free mass (FFM) per min) in normal weight, ‘small-eating’ men were compared with those obtained for normal weight (n 8) and underweight (n 5) ‘large-eating’ men. For the matched groups of ‘large-’ and ‘small-eaters’ there were no differences in resting metabolic rate (RMR) measurements but during controlled daily activities there was a small but significant increase (P < 0.05) in energy expenditure in the ‘large-eaters’. These results contrast with those obtained for the unmatched groups where energy requirements were about 10 % (P < 0.01) higher in the underweight ‘large-eaters’ at rest but were not different during the more energetic (walking) activities. However, after adjustment for differences in FFM between these two groups, the resting energy expenditures of the ‘large-eaters’ (82·54 (SE 1·51) J/kg FFM per min) were similar to those of the ‘small-eaters’ (81·87 (SE 1·51) J/kg FFM per min). Oral temperatures were significantly higher in the matched (0·35–0·65°) and unmatched (0·7–0·9°) ‘large-eaters’ both at rest and during the different activities, but the thermic effect of food (50 kJ/kg FFM) was one fifth lower (not significant) in both groups of ‘large-eaters’. These results provide little evidence for any major metabolic differences between groups of ‘large-eating’ and ‘small-eating’ men.
Nine ‘large-eating’ (approximately 12 MJ/d) and nine ‘small-eating’ (approximately 5.3 MJ/d) women were selected from the population on the basis of diet and activity diaries. At rest and in the post-absorptive state the rate of oxygen consumption (Vo2)/kg fat-free mass (FFM) and rate of carbon dioxide production (Vco2)/kg FFM were 9–17% higher (P < 0.05) in the ‘large-eaters’ than in the ‘small-eaters’. As energy expenditure was increased by walking at 2.4, 3.9 and 5.4 km/h the differences between the two experimental groups for both Vo2/kg FFM and Vco2/kg FFM were decreased to negligible values, but energy expended on a body-weight basis (MJ/kg per min) remained significantly higher (5–10%) in ‘large-eaters’. Oral temperature was also consistently higher (up to 0.5°) in this group both at rest and during sitting, standing and walking activities. Although the average thermic effect of a standardized liquid meal tended to be higher (27%; not significant) in the ‘small-eaters’, the other results demonstrate that the ‘large-eating’ females had a markedly higher rate of energy expenditure at rest and during light physical activities.
The environment for agricultural research and development, technology transfer, and production is marked by conflict among persons with diverse ideas and goals for agriculture. The objective of this analysis was to identify and compare models for researching and problem solving that can provide a conceptual framework for understanding and improving complex situations marked by conflict. The research activities of scientists involved in development of genetically-engineered-herbicide resistance were modeled as reductionist science, technology development, and optimizing systems. An analysis of these models of goal-seeking research indicated that values and assumptions implicit in goals such as greater productivity were not evaluated or questioned. Views of experts influenced development and application of technologies and systems more than concerns of producers and society. A soft systems methodology and research system is proposed to involve more diverse ideas or views of the world, to shift the role of the researcher from expert to facilitator, and to move toward consensus concerning research and technology development in agriculture.
Sixty male adjudicated juvenile delinquents between the ages 14–17, and 20 nondelinquent controls were administered measures of moral reasoning, social convention understanding, interpersonal awareness, socialization, empathy, autonomy, and psychopathy in an effort to explore the relations between moral reasoning, moral sentiment, and antisocial behavior. Not only did the delinquent group evidence developmental delays on all of these direct and indirect tests of morality functioning, but their performance on certain of these measures also differentiated those offenders who were more or less psychopathic. By demonstrating the special contribution of measures of moral will or sentiment to the study of antisocial behavior, these findings serve to underscore the multidimensional character of moral development, and the complexity of the relations between thought and action.
Alasdar Macintyre begins his provocative book After Virtue (1981) with what he refers to as “a disquieting suggestion.” He asks us to imagine that in some previous time, now lost to memory, the natural sciences suffered a monumental catastrophe, perhaps at the hands of some know-nothing political movement, in which laboratories were burned down, books and instruments destroyed, and scientific teaching abolished. Much later, according to this fictional account, other more enlightened people undertake the task of rebuilding science, although they have largely forgotten what it was. In doing so, they salvage the charred remains of half-chapters from books, single pages from articles, and instruments whose use they no longer understand. Out of this patchwork of unrelated fragments they struggle to reembody what was once physics and chemistry and biology. Like a cargo cult filled with persons with names like “handle with care” or “this side up,” the would-be scientists of this scavenger society learn various incantations about “neutrinos” and “atomic weights,” but nobody, or almost nobody, has any grounds for even suspecting that such sloganeering does not sum to the actual doing of natural science in any proper sense at all. That is, the fragmented thinking of the persons living in such a disordered culture would need to be numbered among the symptoms of the disaster whose consequences they were trying to overcome, and as a result, the magnitude and perhaps even the very occurrence of the catastrophe they had suffered would inevitably prove invisible to them.
Adolescents attempt to end their own lives with greater frequency than do either younger or older persons. The aim of this study was to provide a developmental account of this anomaly by examining the contrastive ways in which suicidal and nonsuicidal adolescents reason about their own personal continuity through time. Drawing upon an earlier program of normative research into the links between a maturing sense of personal continuity and the development of a sense of commitment to the future, and capitalizing on recent methodologic advances in the study of young persons' maturing sense of self-continuity, a series of comparisons were made between 30 psychiatrically hospitalized adolescents, at varying degrees of risk to suicide, and a matched control group of their nonsuicidal agemates. The results of this study show that, while almost all of the hospitalized adolescents evidenced some degree of developmental immaturity in their attempts to reason about their own identity across time, the high-risk suicidal group was unique in their special inability to locate any grounds upon which to justify their own continuity through time. These findings are interpreted in terms of their relevance for understanding both the normal identity formation process, and for the diagnosis and treatment of adolescents at special risk to suicide.
We describe our complete sample of flat-spectrum radio sources with fluxes >0.5 Jy selected from the Parkes 2700 MHz catalogue. The sample covers all right ascensions and declinations from +10° to −45°, but excluding the galactic plane (b < 10°), and contains some 400 sources.
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