Maximal work production following two levels of artificially induced metabolic alkalosis

In order to determine the influence of two artificially induced alkalotic states on the ability to perform maximal exercise, six male subjects (mean age, 22.0 years; mean height, 176.8 cm; mean weight, 69.1 kg; mean VO2 max, 3.83 l min-1) were studied during three experimental trials. The subjects performed six 60-s cycling bouts, at a work rate corresponding to 125% VO2 max, with 60 s recovery between work bouts; these regimens were performed 1 h after the ingestion of a solution containing either; I, placebo; II, NaHCO3 in a dosage of 0.15 g per kg body weight; or III, NaHCO3 0.30 g per kg body weight. The sixth work bout was continued until the pedal velocity dropped below 50 rev min-1. Total work done for the entire work period was calculated. Blood samples were taken from a forearm vein prior to the exercise bouts for analysis of pH and HCO3. The results showed a significant pre-exercise difference in pH and HCO3 for all conditions (P less than 0.01). In conditions where artificial alkalosis had been achieved prior to exercise there was significant increase in the work produced: I, 121.6 kJ; II, 133.1 kJ; III, 133.5 kJ (P less than 0.05). The time to fatigue in the six bout was also significantly increased; I, 74.7 s; II, 111.0 s; III, 106.0 p (P less than 0.05). There were no significant differences between conditions II and III. Thus augmentation of the bicarbonate reserves has a significant positive effect on the energy metabolism in interval-type exercise, leading to an increase in the work done and in the time to fatigue.(ABSTRACT TRUNCATED AT 250 WORDS)     

Knowledge Integration and Displaced Volume

This study contrasted spontaneous and reflective knowledge integration instruction delivered using a computer learning environment to enhance understanding of displaced volume. Both forms of instruction provided animated experiments and required students to predict outcomes, observe results, and explain their ideas. In addition, the reflective instruction diagnosed specific inconsistencies in student reasoning and encouraged students to reflect on these dilemmas as well as to construct general principles. We distinguished the impact of instruction on students who believed scientific phenomena are governed by principles (cohesive beliefs) versus students who believed that science is a collection of unrelated facts (dissociated beliefs). Students typically held multiple models of displacement, using different explanations depending on the form of assessment. For example, we found that 17% of these middle school students made accurate predictions about displacement experiments prior to instruction and 25% could construct an accurate general principle. However, only 12% consistently used the same explanation across assessments. After instruction, students were more accurate and more consistent: over 50% accurately predicted experimental outcomes, 79% gave an accurate general principle, and about 40% gave consistent responses. We found no advantages for enhanced animations over straightforward animated experiments. The reflective integration instruction led to more substantial long-term changes in student understanding than did spontaneous integration instruction. Furthermore, on a delayed posttest we found that students with cohesive beliefs not only sustained their understanding of displaced volume, but, when exposed to reflective integration instruction, actually continued to construct more predictive views following instruction. In contrast, students with dissociated beliefs made no long-term progress independent of the form of instruction.     

Fostering empathy in undergraduate health science majors through the reconciliation of objectivity and subjectivity: An integrated approach

The demand for empathetic health care practitioners requires an academic curriculum suited to that need. Here we describe a series of integrated activities that were designed to foster empathy in undergraduate health science majors. By combining content and pedagogical approaches from the humanities and sciences, we asked students to reconcile objective and subjective modes of understanding the human body as a learning object. Preliminary evaluations of student behavior, written student responses, and survey results are offered as support for our conclusion that the integration of a humanities perspective into the Anatomy classroom at University of Minnesota Rochester can facilitate the process of developing student empathy through the reconciliation of objective and subjective modes. Furthermore, students were able to apply this understanding to images on the page or screen, to living human learning objects and human cadavers. Although to claim that these activities in themselves can stymie the stasis/decline of empathy that health science students report would be patently false, we conclude that similar approaches could offer an avenue by which other educators might develop similar activities that, in aggregate, might have a lasting effect from the undergraduate through the graduate level of training in the health sciences. Anat Sci Educ. © 2012 American Association of Anatomists.     

Wild botanic gardens as valuable resources for innovative environmental education programmes in Latin America

Wild botanic gardens consist of natural or semi-natural land remnants immersed in large urban areas or botanic gardens, which are managed for purposes of biodiversity preservation and public recreation. In Latin America, they tend to be affected by budget limitations; however, they serve as valuable resources that permit the development of innovative environmental education programmes. Specifically, we are considering the appropriateness of implementing critical environmental education and socio-constructivist programmes. As for practical considerations, it is important to include diverse epistemologies, and therefore, strategies or procedures characteristic of science teaching, such as problem-based learning, together with other characteristics of social activism and popular education initiatives, such as assemblies or meetings, and others characteristic of more traditional and indigenous worldviews, such as celebrations of the earth. In this way, Latin American wild botanic gardens may play a role in constructing environmentally responsible societies and the nurturing of a culture of reflective inquiry.     

Equity Traps Redux: Inequitable Access to Foreign Language Courses for African American High School Students

Although much of the current educational research literature on achievement gaps has focused on core curricular areas in public schools, few have focused on racially identifiable gaps in non-core areas such as high school foreign languages. These achievement, and thus advancement, gaps often result in the under-representation of students of color in higher level foreign language classes. This can have long-range negative consequences for students, such as lacking the foreign language credits needed for admission into major universities. Thus, in this qualitative study, we researched the perceptions of teachers, counselors, and school leaders at a racially diverse urban high school in central Texas concerning the enrollment, achievement, and advancement of African American students in high school foreign language courses. The results indicate that equity traps—deficit views, racial erasure, and paralogical beliefs and behaviors—advanced over a decade ago (McKenzie &; Scheurich, 2004 McKenzie, K. B., &; Scheurich, J. J. (2004). Equity traps: A useful construct for preparing principals to lead schools that are successful with racially diverse students. Educational Administration Quarterly, 40(5), 601–632.[Crossref], [Web of Science ®] , [Google Scholar]) are continuing and even thriving among teachers, counselors, and school leaders in public schools. These equity traps contribute to the foreign language achievement gap, resulting in diminished educational opportunities for African American students. Moreover, we propose that an additional equity trap is at play—organizational constraints—which are the structural obstacles that serve to abet and perpetuate the negative beliefs, behaviors, attitudes, and assumptions exposed in the original equity traps. We conclude this article with recommendations for policy makers and practitioners and offer direction for future research.     

The impact of individual consultation on student ratings of teaching

Abstract

The present study addressed the impact of individual consultation on teaching improvement as measured by changes in student ratings. Subjects included 91 professors who presented naturally for individual consultation services over a seven‐year period at the teaching centre of a Canadian university. Interventions by the consultant fell into three categories: 1) Feedback‐Consultation, 2) Feedback‐Consultation‐Class Observation, and 3) Feedback‐Consultation‐Class Observation and Student Consultation. End of term student ratings for the course that was the subject of the consultation were compared with student ratings for the same course taught between one and three years prior to the consultation service, and for the same course taught between one to three years following consultation. The results showed that, overall, consultation was effective in improving the quality of the consultees’ teaching, as evidenced by an increase in mean student ratings of instruction. This effect persisted post consultation. Not all intervention groups, however, showed the same pattern of results. Change was evident immediately after the intervention except in the case of brief consultation, although follow‐up data showed improved teaching for the latter group. Control data provided evidence that the change in student ratings post consultation could reasonably be attributed to consultation effects.     

Encoding of spatial information in images of an outdoor scene by pigeons and humans

Pigeons and adult humans searched for a 2-cm² unmarked goal in digitized images of an outdoor scene presented on a touch-screen monitor. In Experiment 1, the scene contained three landmarks near the goal and a visually rich background. Six training images presented the scene from different viewing directions and distances. Subsequent unreinforced tests in which landmark or background cues were removed or shifted revealed that pigeons’ search was controlled by both proximal landmarks and background cues, whereas humans relied only on the proximal landmarks. Pigeons’ search accuracy dropped substantially when they were presented with novel views of the same scene, whereas humans showed perfect transfer to novel views. In Experiment 2, pigeons with previous outdoor experience and humans were trained with 28 views of an outdoor scene. Both pigeons and humans transferred well to novel views of the scene. This positive transfer suggests that, under some conditions, pigeons, like humans, may encode the three-dimensional spatial information in images of a scene.     

Validating Measurement of Knowledge Integration in Science Using Multiple-Choice and Explanation Items

This study explores measurement of a construct called knowledge integration in science using multiple-choice and explanation items. We use construct and instructional validity evidence to examine the role multiple-choice and explanation items plays in measuring students' knowledge integration ability. For construct validity, we analyze item properties such as alignment, discrimination, and target range on the knowledge integration scale using a Rasch Partial Credit Model analysis. For instructional validity, we test the sensitivity of multiple-choice and explanation items to knowledge integration instruction using a cohort comparison design. Results show that (1) one third of correct multiple-choice responses are aligned with higher levels of knowledge integration while three quarters of incorrect multiple-choice responses are aligned with lower levels of knowledge integration, (2) explanation items discriminate between high and low knowledge integration ability students much more effectively than multiple-choice items, (3) explanation items measure a wider range of knowledge integration levels than multiple-choice items, and (4) explanation items are more sensitive to knowledge integration instruction than multiple-choice items.