Direct and indirect calorimetry of lactate oxidation: implications for whole-body energy expenditure

Whole-body energy expenditure for heavy/severe exercise is currently accounted for by either: (1) anaerobic and oxygen uptake measures during exercise where recovery energy expenditure is omitted; or (2) oxygen uptake during, and an EPOC (excess post-exercise oxygen consumption), measure following exercise where substrate level phosphorylation during exercise is considered part of EPOC. Simultaneous direct/indirect calorimetry enabled us to determine if a thermodynamic reversal (i.e. heat consumption) takes place as the highly exothermic pyruvate to lactate reaction proceeds in the opposite direction. Reversibility implies that oxygen uptake (e.g. EPOC) can indeed account for rapid glycolytic ATP production regardless if lactate is formed or not (e.g. 1.2 g glucose catabolism = 20.9 kJ x l O2(-1)). Cultured hybrid cells and mouse cardiac muscle fibres were utilized in simultaneous calorimetry and respirometry experiments where pyruvate or lactate was predominantly oxidized. The calorimetric to respiratory ratio was determined using heat flux (pW x cell(-1)) and oxygen flux (pmol x s(-1) cell(-1)) measures. Ten cell experiments gave calorimetric to respiratory ratios that showed no statistical difference (P= 0.97) whether cells respired predominantly on lactate (-516+/-53 kJ x mol O2(-1)) or pyruvate (- 517+/-89 kJ x mol O2(-1)). In three cardiac preparations, the calorimetric to respiratory ratio was -502+/-15 kJ x mol O2(-1) for lactate and -506+/-47 kJ x mol O2(-1) for pyruvate, again a non-significant difference (P= 0.91). Heat consumption did not occur during lactate oxidation. These results suggest that rapid glycolytic ATP and lactate production, and lactate oxidation, are both independently associated with heat production and thus represent separate and additive components to the measurement of total energy expenditure for exercise and recovery.     

Supporting High School Student Accomplishment of Biology Content Using Interactive Computer-Based Curricular Case Studies

Research in Science Education - Research into the efficacy of modules featuring dynamic visualizations, case studies, and interactive learning environments is reported here. This quasi-experimental...     

AV Production activities in school systems

Educational technology research and development -     

Computer-aided publishing and open learning materials

The authors discuss the potential impact of computer-aided publishing hardware and software on the production of distance education and self-instructional study material. They compare the capabilities of computer-aided publishing systems with those of other equipment. General typographic design criteria are raised.
The implications of the availability of computer-aided publishing systems are then discussed in relation to the production of printed learning materials. Computer-aided publishing systems have benefits in revealing instructional design strategies, aiding development and revision, and in the production and incorporation of graphics. However, an ability to operate the software does not guarantee the production of high quality printed materials. The knowledge and skills of the graphic designer are as necessary as ever.     

A Comparison of the Expressive Language Opportunities Provided by Shared Book Reading and Facilitated Play for Young Children with Mild to Moderate Intellectual Disabilities

ABSTRACT In this study, which aimed to compare the expressive language opportunities provided by shared book reading and facilitated play, the language of 22 young children with mild to moderate intellectual disabilities and delayed language was examined. The children were videotaped while interacting with a facilitator during a session that included both book reading and play. Two different protocols were used to analyse the children's language in both conditions. The first protocol was used to document the number of intelligible, unintelligible and inaudible utterances and the second protocol was used to examine the intelligible utterances in relation to their complexity and function. The findings indicated that shared book reading elicited more language, more intelligible language and more complex language than the facilitated play condition. Results also suggested that shared book reading allowed for more conversational interaction between the children and the facilitators. The indications are that shared book reading may provide better opportunities than facilitated play for collecting a representative language sample from young children with mild to moderate intellectual disabilities.     

Teaching under Lockdown: the experiences of London English teachers

ABSTRACT

In response to the Covid-19 pandemic, on 18 March 2020, Prime Minister Boris Johnson announced the immediate closure of schools in England. (The closure was not absolute: schools would remain open for vulnerable children and the children of key workers. In practice, though, very few children have continued to attend.) In what follows, nine English teachers reflect on their experience of teaching under lockdown.     

The Accidental Archivists: Lessons Learned from a Digital Archive Project

This article tells the story of the University of Colorado Law Library's successful effort to develop its first digital archive. The sudden death of the law school's dean was the catalyst for this project, with a goal to unveil the archive at a memorial symposium scheduled nine months in the future. The University of Colorado Law Library staff had never tackled a project of this type or scale before. This article discusses the technological, cataloging, and management issues that were encountered during the project. It also provides advice and tips on how librarians in their own institutions can accomplish such a project.