University of Manitoba

About: University of Manitoba is a education organization based out in Winnipeg, Manitoba, Canada. It is known for research contribution in the topics: Population & Health care. The organization has 31888 authors who have published 66592 publications receiving 2095493 citations.

The effect of talk and writing on learning science: An exploratory study

Abstract: This study investigated the role of talk and writing on learning science. The purpose was to explore the effect of talk, writing, and talk and writing on the learning and retention of simple and integrated knowledge, and to describe the mechanisms by which talk and writing mediate these processes. Forty-three students were randomly assigned to four groups, all stratified for gender and ability. At intervals during an instructional unit, three treatment groups received problem tasks that involved constructing scientific explanations for real-world applications of ecological concepts. A control group received simpler descriptive tasks based on similar content. Students in the talk-only treatment group (T) discussed the problem tasks in small peer groups. Students in the writing-only treatment group (W) individually wrote responses for each of the tasks, but without first talking to other students. Students in the combined talk and writing treatment group (TW) discussed the problems in groups prior to individually writing their explanations. Dependent variables included simple, integrated, and total knowledge scores based on multiple-choice tests, essay questions, and concept maps obtained at three timepoints during the study: a pretest; an immediate posttest; and a delayed posttest. Records of student talk and writing were also analyzed to describe the mechanisms involved. The findings suggest that talk is important for sharing, clarifying, and distributing knowledge among peers, while asking questions, hypothesizing, explaining, and formulating ideas together are all important mechanisms during peer discussions. Analytical writing is an important tool for transforming rudimentary ideas into knowledge that is more coherent and structured. Furthermore, talk combined with writing appears to enhance the retention of science learning over time. Moreover, gender and ability may be important mediating variables that determine the effectiveness of talk and writing for enhancing learning. © 2000 John Wiley & Sons, Inc. Sci Ed84:566–593, 2000.

Mechanisms of bactericidal action of cinnamaldehyde against Listeria monocytogenes and of eugenol against L. monocytogenes and Lactobacillus sakei.

Abstract: The spice oil components eugenol and cinnamaldehyde possess activity against both gram-positive and gram-negative bacteria, but the mechanisms of action remain obscure In broth media at 20°C, 5 mM eugenol or 30 mM cinnamaldehyde was bactericidal (>1-log reduction in the number of CFU per milliliter in 1 h) to Listeria monocytogenes At a concentration of 6 mM eugenol was bactericidal to Lactobacillus sakei, but treatment with 05 M cinnamaldehyde had no significant effect To investigate the role of interference with energy generation in the mechanism of action, the cellular and extracellular ATP levels of cells in HEPES buffer at 20°C were measured Treatment of nonenergized L monocytogenes with 5 mM eugenol, 40 mM cinnamaldehyde, or 10 μM carbonyl cyanide m-chlorophenylhydrazone (CCCP) for 5 min prevented an increase in the cellular ATP concentration upon addition of glucose Treatment of energized L monocytogenes with 40 mM cinnamaldehyde or 10 μM CCCP caused a rapid decline in cellular ATP levels, but 5 mM eugenol had no effect on cellular ATP Treatment of L sakei with 10 mM eugenol prevented ATP generation by nonenergized cells and had no effect on the cellular ATP of energized cells CCCP at a concentration of 100 μM had no significant effect on the cellular ATP of L sakei No significant changes in extracellular ATP were observed Due to their rapidity, effects on energy generation clearly play a major role in the activity of eugenol and cinnamaldehyde at bactericidal concentrations The possible mechanisms of inhibition of energy generation are inhibition of glucose uptake or utilization of glucose and effects on membrane permeability

A fundamental approach to transformer thermal modeling. I. Theory and equivalent circuit

Abstract: A simple equivalent circuit to represent the thermal heat flow equations for power transformers is presented. Key features are the use of a current source analogy to represent heat input due to losses, and a nonlinear resistor analogy to represent the effect of air or oil cooling convection currents. The effect was first quantified in 1817. It is shown that the idea of "exponential response" is not the best way to think of the dynamics of the situation. It is also shown that one can consider ambient temperature to be a variable input to the system, and that it is properly represented as an ideal voltage source.

Multiple wheat genomes reveal global variation in modern breeding.

Abstract: Advances in genomics have expedited the improvement of several agriculturally important crops but similar efforts in wheat (Triticum spp.) have been more challenging. This is largely owing to the size and complexity of the wheat genome1, and the lack of genome-assembly data for multiple wheat lines2,3. Here we generated ten chromosome pseudomolecule and five scaffold assemblies of hexaploid wheat to explore the genomic diversity among wheat lines from global breeding programs. Comparative analysis revealed extensive structural rearrangements, introgressions from wild relatives and differences in gene content resulting from complex breeding histories aimed at improving adaptation to diverse environments, grain yield and quality, and resistance to stresses4,5. We provide examples outlining the utility of these genomes, including a detailed multi-genome-derived nucleotide-binding leucine-rich repeat protein repertoire involved in disease resistance and the characterization of Sm16, a gene associated with insect resistance. These genome assemblies will provide a basis for functional gene discovery and breeding to deliver the next generation of modern wheat cultivars.

Clinical Practice Guideline for the Management of Asymptomatic Bacteriuria: 2019 Update by the Infectious Diseases Society of America.

Abstract: Asymptomatic bacteriuria (ASB) is a common finding in many populations, including healthy women and persons with underlying urologic abnormalities. The 2005 guideline from the Infectious Diseases Society of America recommended that ASB should be screened for and treated only in pregnant women or in an individual prior to undergoing invasive urologic procedures. Treatment was not recommended for healthy women; older women or men; or persons with diabetes, indwelling catheters, or spinal cord injury. The guideline did not address children and some adult populations, including patients with neutropenia, solid organ transplants, and nonurologic surgery. In the years since the publication of the guideline, further information relevant to ASB has become available. In addition, antimicrobial treatment of ASB has been recognized as an important contributor to inappropriate antimicrobial use, which promotes emergence of antimicrobial resistance. The current guideline updates the recommendations of the 2005 guideline, includes new recommendations for populations not previously addressed, and, where relevant, addresses the interpretation of nonlocalizing clinical symptoms in populations with a high prevalence of ASB.