An effective strategy for integrating ethics across the curriculum in engineering: An ABET 2000 challenge

This paper describes a one-day workshop format for introducing ethics into the engineering curriculum prepared at the University of Puerto Rico at Mayagüez (UPRM). It responds to the ethics criteria newly integrated into the accreditation process by the Accreditation Board of Engineering and Technology (ABET). It also employs an ethics across the curriculum (EAC) approach; engineers identify the ethical issues, write cases that dramatize these issues, and then develop exercises making use of these cases that are specially tailored to mainstream engineering classes.The different activities and strategies employed in this workshop are set forth. Specific references are made to the cases and exercises developed as a result of these workshops. The paper ends by summarizing the different assessments made of the workshop by addressing the following questions: how did it contribute to the overall ABET effort at UPRM; could other universities benefit from a similar activity; and how did the participants evaluate the workshop?     

Learning to control brain activity: a review of the production and control of EEG components for driving brain-computer interface (BCI) systems

Brain-computer interface (BCI) technology relies on the ability of individuals to voluntarily and reliably produce changes in their electroencephalographic (EEG) activity. The present paper reviews research on cognitive tasks and other methods of generating and controlling specific changes in EEG activity that can be used to drive BCI systems. To date, motor imagery has been the most commonly used task. This paper explores the possibility that other cognitive tasks, including those used in imaging studies, may prove to be more effective. Other factors which influence performance are also considered in relation to selection of tasks, as well as training of subjects.     

Interhemispheric effects of simulated lesions in a neural model of single-word reading

A neural model consisting of paired cerebral hemispheric regions interacting via homotopic callosal connections was trained to generate pronunciations for 50 monosyllabic words. Lateralization of this task occurred readily when different underlying cortical asymmetries were present. Following simulated focal cortical lesions of systematically varied sizes, acute changes in the distribution of cortical activation were found to be most consistent with experimental data when interhemispheric interactions were assumed to be excitatory. During subsequent recovery, the contribution of the unlesioned hemispheric region to performance improvement was a function of both the amount of preexisting lateralization and the side and size of the lesion. These results are discussed in the context of unresolved issues concerning the mechanisms underlying language lateralization, the nature of interhemispheric interactions, and the role of the nondominant hemisphere in recovery from adult aphasia.     

蛋白质化学与分子生物学携手前进

蛋白质化学的发展历经了几次重大的转变,分析仪器的商品化使蛋白质从实验室走向市场;一级结构信息促进了多肽的合成与改造;分子生物学技术的成熟使人们从设计改造功能蛋白转向设计基因,并尝试进行基因治疗和ＤＮＡ免疫。这些转变,使蛋白质化学技术与分子生物学技术成为人们手中的工具,为人们研究生命拓宽了思路。     

Pigeons' choices in situations of diminishing returns: fixed- versus progressive-ratio schedules.

In two different discrete-trial procedures, pigeons were faced with choices between fixed-ratio and progressive-ratio schedules. The latter schedules entail diminishing returns, a feature analogous to foraging situations in the wild. In the first condition (no reset), subjects chose between a progressive-ratio schedule that increased in increments of 20 throughout a session and a fixed-ratio schedule that was constant across blocks of sessions. The size of the fixed ratio was varied parametrically through an ascending and then a descending series. In the reset condition, the same fixed-ratio values were used, but each selection (and completion) of the fixed ratio reset the progressive-ratio schedule back to its minimal value. In the no-reset procedure, the pigeons tended to cease selecting the progressive ratio when it equaled or slightly exceeded the fixed-ratio value, whereas in reset, they chose the fixed ratio well in advance of that equality point. These results indicate sensitivity to molar as well as to molecular reinforcement rates, and those molar relationships are similar to predictions based on the marginal value theorem of optimal foraging theory (e.g., Charnov, 1976). However, although previous results with monkeys (Hineline & Sodetz, 1987) appeared to minimize responses per reinforcement, the present results corresponded more closely to predictions based on sums-of-reciprocals of distance from point of choice to each of the next four reinforcers. Results obtained by Hodos and Trumbule (1967) with chimpanzees in a similar procedure were intermediate between these two relationships. Variability of choices, as well as median choice points, differed between the reset and no-reset conditions.(ABSTRACT TRUNCATED AT 250 WORDS)     

Adapting to the surface: A comparison of handwriting measures when writing on a tablet computer and on paper

Our study addresses the following research questions: Are there differences between handwriting movements on paper and on a tablet computer? Can experienced writers, such as most adults, adapt their graphomotor execution during writing to a rather unfamiliar surface for instance a tablet computer?We examined the handwriting performance of adults in three tasks with different complexity: (a) graphomotor abilities, (b) visuomotor abilities and (c) handwriting. Each participant performed each task twice, once on paper and once on a tablet computer with a pen.We tested 25 participants by measuring their writing duration, in air time, number of pen lifts, writing velocity and number of inversions in velocity. The data were analyzed using linear mixed-effects modeling with repeated measures.Our results reveal differences between writing on paper and on a tablet computer which were partly task-dependent. Our findings also show that participants were able to adapt their graphomotor execution to the smoother surface of the tablet computer during the tasks.     

Deformation twinning-mediated pseudoelasticity in metal–graphene nanolayered membrane

In this study, we investigated the deformation behaviour of metal–graphene nanolayered composites for five face-centred cubic metals under compression using molecular dynamics simulations. It was found that by increasing the thickness of the individual metal layers, the composite strength increased, while the deformation mechanism changed from buckling to deformation twining in Cu, Au and Ag, which was absent in the monolithic form of those metals of the same orientation and size. The deformation twinning was found to be enabled by the graphene layer, which introduced pseudoelasticity and shape memory effects in the nanolayered membrane with more than 15% recoverable compressive strain.     

Using the simultaneous protocol to study equivalence class formation: the facilitating effects of nodal number and size of previously established equivalence classes

The emergence of equivalence classes in college students is unlikely when all baseline relations are trained concurrently and all probes for emergent relations are then introduced concurrently (the simultaneous protocol). This experiment showed how the number of nodes and the size of previously established equivalence classes enhanced the emergence of new equivalence classes under the simultaneous protocol. First, one-node three-, five-, or seven-member classes or three-node five- or seven-member classes were established with college students. A sixth group received no pretraining. Then, the simultaneous protocol was used to establish new three-node five-member equivalence classes with all students. The speed and variability with which the baseline relations were established in the simultaneous protocol were inverse functions of number of nodes in the previously established classes, but not of their size. The percentage of subjects who showed the emergence of new equivalence classes under the simultaneous protocol was a direct function of number of nodes and size of pretrained classes. The additional time spent for pretraining greatly reduced the total training time needed to produce individuals who showed the emergence of classes under the simultaneous protocol. The total time saved was a direct function of number of nodes and number of stimuli in the pretrained classes.     

Optimizing Expression of the Common Human Genome for Child Development

Molecular biology has moved the gene-environment issue in behavior genetics to how and when expression of the human genome is triggered and maintained. How does environment influence gene expression? How many genes are expressed in producing a given behavior? The genome is a data bank and does not automatically create a working brain. The body and brain grow well when (a) endocrine hormones initiate and promote the expression of genes, (b) nutrition is sufficient to sustain the production of proteins, and (c) stress does not suppress gene expression. The growth of brain synapses also requires appropriate neural stimulation. To study gene expression, it is essential to view the complex biology of the cell from a system context that includes the entire genome plus the biological and psychological environments. Optimizing geneexpression for child growth can be achieved by a balance of medicine, nutrition, and appropriate physical, educational, and psychological environments.