827 research outputs found
The Teacher\u27s Role in Facilitating Memory and Study Strategy Development in the Elementary School Classroom
The efforts of 69 elementary school teachers to instruct children in cognitive processing activities were observed. Although the teaching of such activities was relatively infrequent, it varied by grade (occurring more often in grades 2-3 than in higher or lower grades) and by the content of instruction. Teachers of grade 4 and above more often provided rationales for the use of cognitive strategies than did teachers of younger children. In a second study, children of three achievement levels were selected from classrooms in which teachers varied in their use of suggestions regarding cognitive processes. Subsequent to training in the use of a memory strategy, children\u27s performance on a maintenance trial was evaluated: Among average and low achievers, those whose teachers were relatively high in strategy suggestions showed better maintenance and more deliberate use of the trained strategy than did children whose teachers rarely made strategy suggestions. The role of school experience in the development of children\u27s memory skills is discussed
Are methodological quality and completeness of reporting associated with citation-based measures of publication impact? A secondary analysis of a systematic review of dementia biomarker studies
Objective: To determine whether methodological and reporting quality are associated with surrogate measures of publication impact in the field of dementia biomarker studies.
Methods: We assessed dementia biomarker studies included in a previous systematic review in terms of methodological and reporting quality using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) and Standards for Reporting of Diagnostic Accuracy (STARD), respectively. We extracted additional study and journal-related data from each publication to account for factors shown to be associated with impact in previous research. We explored associations between potential determinants and measures of publication impact in univariable and stepwise multivariable linear regression analyses.
Outcome measures: We aimed to collect data on four measures of publication impact: two traditional measures—average number of citations per year and 5-year impact factor of the publishing journal and two alternative measures—the Altmetric Attention Score and counts of electronic downloads.
Results: The systematic review included 142 studies. Due to limited data, Altmetric Attention Scores and electronic downloads were excluded from the analysis, leaving traditional metrics as the only analysed outcome measures. We found no relationship between QUADAS and traditional metrics. Citation rates were independently associated with 5-year journal impact factor (β=0.42; p<0.001), journal subject area (β=0.39; p<0.001), number of years since publication (β=-0.29; p<0.001) and STARD (β=0.13; p<0.05). Independent determinants of 5-year journal impact factor were citation rates (β=0.45; p<0.001), statement on conflict of interest (β=0.22; p<0.01) and baseline sample size (β=0.15; p<0.05).
Conclusions: Citation rates and 5-year journal impact factor appear to measure different dimensions of impact. Citation rates were weakly associated with completeness of reporting, while neither traditional metric was related to methodological rigour. Our results suggest that high publication usage and journal outlet is not a guarantee of quality and readers should critically appraise all papers regardless of presumed impact
How Do Teachers Teach Memory Skills?
Research on teachers\u27 efforts to influence the ways in which children approach memory tasks and understand and regulate their own memory processes has been limited, possibly because of the restrictive views of memory held by cognitive theories that have previously guided research efforts. A more complex perspective on the memory skills that develop over the elementary school years has been elaborated by developmental psychologists and information-processing theorists, but their work has had limited influence on either teacher-training practices or research in teaching. In order to begin to apply this newer perspective to an understanding of classroom teaching processes, research needs to consider teacher practices and expectations for children\u27s learning and memory. A program of research that has been concerned with how teachers teach memory and metacognitive skills and with teachers\u27 views of memory processes is summarized in this article, and implications for teacher training are discussed
Historical and contemporary perspectives on the sediments of Lake Rotorua
Lake Rotorua is probably the oldest continuously inundated lake in New Zealand, occupying a caldera formed by or closely associated with the eruption of the Mamaku ignimbrite and the collapse of the Rotorua caldera (Healy, 1975; Lowe and Green, 1991). The lake has undergone drastic changes in size and depth as a result of tectonics, volcanic activity and erosion. Since the Rotoehu eruption, (~60 kyr), the lake level has fluctuated between 120 m above present (280 m asl) and 10 m below present level. The modern lake covers an area of 79 km2 and has a mean depth of 10 m. Despite its long history of sedimentation, Lake Rotorua has an irregular bathymetry with features including faulted blocks, slumps, hydrothermal explosion craters, springs and large methane discharge pock marks
Transfer Entropy as a Log-likelihood Ratio
Transfer entropy, an information-theoretic measure of time-directed
information transfer between joint processes, has steadily gained popularity in
the analysis of complex stochastic dynamics in diverse fields, including the
neurosciences, ecology, climatology and econometrics. We show that for a broad
class of predictive models, the log-likelihood ratio test statistic for the
null hypothesis of zero transfer entropy is a consistent estimator for the
transfer entropy itself. For finite Markov chains, furthermore, no explicit
model is required. In the general case, an asymptotic chi-squared distribution
is established for the transfer entropy estimator. The result generalises the
equivalence in the Gaussian case of transfer entropy and Granger causality, a
statistical notion of causal influence based on prediction via vector
autoregression, and establishes a fundamental connection between directed
information transfer and causality in the Wiener-Granger sense
Fog City Comics, No. 1
3 numbers black-and-white illustrations. Frequency: Annual Publication dates: Began with no. 1 (September, 1977); ceased with no. 3 (June, 1979). Not for sale to children. Fog City Comics is a three-issue anthology published in Vancouver (the fog city, get it?) by Stampart. They are notable for giving us three terrific Rand Holmes covers and one Holmes story in each of the books. Edited by Terry Hamilton, the series is not one of the stronger contributions to the post-golden-era underground ouevre, but there are certainly some gems to be found. The first issue features funny animal stories throughout, a theme that has seen its share of failures in the past and this is probably one of them. The third issue is 68 pages and easily the best of the series, with a brilliant self-reflective story from Rand Holmes, an epic tale from George Metzger, and several decent contributions from Brent Boates. Library has No. 1 (September, 1977) & No. 3 (1979). The Adler Archive of Underground Comix, Gift of Bill Adler.https://digitalcommons.risd.edu/specialcollections_adlerarchive_undergroundcomix/1057/thumbnail.jp
Development of a method for measuring quasi-static stiffness of snowboard wrist protectors
In snowboarding, the wrist is the most common injury site, as snowboarders often put their arms out to cushion a fall. This can result in a compressive load through the carpals coupled with wrist hyperextension, leading to sprains or fractures. Wrist protectors are worn by snowboarders in an effort to reduce injury risk, by decreasing impact forces and limiting wrist hyperextension during falls. However, there is no international standard or universally-accepted performance specification that these products should conform to, resulting in an inability to judge which design elements offer the most protection. EN 14120:2003 prescribes requirements that roller sports wrist protectors should meet, and has been identified as a starting point for developing a snowboarding-specific standard. This paper critiques the EN 14120:2003 test protocol and goes on to present a mechanical test for assessing the ability of snowboard wrist protectors to resist extension of the hand under an applied load. A bespoke rig incorporating the hand/arm surrogate from EN 14120:2003 was mounted to a uniaxial test machine, and wrist protectors were strapped to the surrogate at a set tightness (tight, moderate, loose). Linear displacement of the uniaxial test machine was
transferred to angular displacement of the hand via a galvanised steel cable passing through a low friction pulley. Linear displacement was set to 200 mm/min and force was measured at the load cell until 80 N was reached. The test, presented here, found that the ability of the protectors to limit hand extension was dependent on how tightly they were fitted to the surrogate; therefore, strap tightness must be accounted for during further wrist protector safety assessments. This test provides a repeatable way to characterise the ability of snowboarding wrist protectors to limit wrist extension
Effect of surrogate design on the measured stiffness of snowboarding wrist protectors
In snowboarding, the wrist is the most common injury site, as snowboarders often put their arms out to cushion a fall. This can result in a compressive load through the carpals coupled with wrist hyperextension, leading to ligament sprains or carpal and forearm bone fractures. Wrist protectors are worn by snowboarders in an effort to reduce injury risk, by decreasing peak impact forces and limiting wrist extension to prevent hyperextension during falls. There is no international standard or universally accepted performance specification that snowboarding wrist protectors should conform to, resulting in an inability to judge which designs offer the best protection. This study investigated how surrogate arm design affected the stiffness of wrist protectors during quasi-static mechanical testing. Three surrogate arms with increasing design complexity were used to test three wrist protectors. The results show that surrogate design does influence the stiffness of snowboarding wrist protectors. Given that the surrogate does influence protector performance, it is recommended that a standard surrogate design is established for research and product testing
Evidence for quantum confinement in the photoluminescence of porous Si and SiGe
We have used anodization techniques to process porous surface regions in p-type Czochralski Si and in p-type Si0.85Ge0.15 epitaxial layers grown by molecular beam epitaxy. The SiGe layers were unrelaxed before processing. We have observed strong near-infrared and visible light emission from both systems. Analysis of the radiative and nonradiative recombination processes indicate that the emission is consistent with the decay of excitons localized in structures of one or zero dimensions
Synthesis and structural analysis of the N-terminal domain of the thyroid hormone-binding protein transthyretin
Transthyretin (TTR) is a 55 kDa protein responsible for the transport of thyroid hormones and retinol in human serum. Misfolded forms of the protein are implicated in the amyloid diseases familial amyloidotic polyneuropathy and senile systemic amyloidosis. Its folding properties and stabilization by ligands are of current interest due to their importance in understanding and combating these diseases. To assist in such studies we developed a method for the solid phase synthesis of the monomeric unit of a TTR analogue and its folding to form a functional 55 kDa tetramer. The monomeric unit of the protein was chemically synthesized in three parts, comprising amino acid residues 151, 5499 and 102127, and ligated using chemoselective thioether ligation chemistry. The synthetic protein was folded and assembled to a tetrameric structure in the presence of the TTRs native ligand, thyroxine, as shown by gel filtration chromatography, native gel electrophoresis, TTR antibody recognition and thyroid hormone binding. In the current study the solution structure of the first of these fragment peptides, TTR(151) is examined to determine its intrinsic propensity to form beta-sheet structure, potentially involved in amyloid fibril formation by TTR. Despite the presence of extensive beta-structure in the native form of the protein, the Nterminal fragment adopts an essentially random coil conformation in solution
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