169,736 research outputs found
The process of knowledge re-description as underlying mechanism for the development of children’s problem-solving strategies: an example from arithmetic
No full textThis paper reports on a study which aimed at exploring ways by which 5-6 year-old children organise different pieces of knowledge to develop strategies for solving a specific arithmetical task and furthermore, ways by which children move beyond their successful problem solving approaches to the acquisition of increased control over the procedural and conceptual knowledge that supports their problem solving success. The paper considers the emerging theory of Representational-Redescription which supports the idea of ‘success-based’ cognitive change and argues that new knowledge can be constructed by a process of internal exploitation of knowledge that already exists in the cognitive system of the problem solver. In problem solving, the notion of Representational-Redescription has been studied in spatial, physics, linguistic and notational tasks but currently, it is under-researched in mathematics. The paper presents outcomes from a study which focused on ten cases. The microgenetic method was used for the study of changes in children’s problem solving. This entailed the design of a sequence of sessions during which children were individually involved in solving a specific form of additive task, more than once, and after they had been successful in solving it. The microgenetic method was combined with the clinical method of interviewing. The paper presents a specific path of after-success strategy change. This path of change indicated children’s movement from initial success-oriented behaviour to an organisation-oriented phase during which new strategies were introduced or known strategies were evolved procedurally and conceptually. The paper explains the general analytical direction which was followed to reveal different levels of knowledge accessibility and explicitness which supported children’s main strategy during the after-success change process. These findings support the idea that learning follows not only from failure but also from success, and that the Representational-Redescription theory can offer an additional insight to the complex nature of learning processe
An analysis of the presentation of the equals sign in Grade 1 Greek textbooks
No full textYoung children often develop a partial, operational understanding of the equals sign that refers to completing an action, such as getting the answer to an addition or multiplication question, and fail to develop a relational understanding of the equals sign as a symbol that denotes equivalence. A partial view of the equals sign as an operator can be the result of primary-age pupils’ overexposure to canonical equations such as a+b=c. This paper presents a preliminary analysis of the different syntaxes and formats used to present equality statements in the Grade 1 textbooks in Greece. The quantitative analysis reveals an overemphasis on presenting the equals sign within canonical equations. However, qualitative analysis reveals that the equals sign is first introduced in a context that conveys the idea of equivalence relation and is presented within an interesting mix of symbolic and non-symbolic contexts which may minimise the tendency to interpret the equals sign exclusively as an operator
Context variation and syntax nuances of the equal sign in elementary school mathematics
No full textExisting research suggests that young children can develop a partial understanding of the equal sign as an operator rather than as a relational symbol of equivalence. This partial understanding can be the result of overemphasis on canonical equation syntaxes of the type a + b = c in elementary school mathematics. This paper presents an examination of context and syntax nuances of relevant sections from the Grade-1 Greek series of textbooks and workbooks. Using a conceptual framework of context variation, the analysis shows qualitative differences between equations of similar syntax and provides a nuanced determination of contextual and structural aspects of ‘variation’ in how the equal sign is presented in elementary mathematics. The paper proposes that since equations have context-specific meanings, context variations should constitute a separate element of analysis when investigating how the equal sign is presented. The implication for practice and future research is that nuanced considerations of equation syntax within varied contexts are needed for elaborating analyses of the equal sign presentation that move beyond dichotomized categorizations of canonical/non-canonical syntaxes
Preschool children’s notations for denoting ordinal position and quantity
No full textThe research is funded by The Leverhulme Trust (RPG-2019-330), in the UK
Deconstructing ‘good practice’ teaching videos: An analysis of pre-service teachers’ reflections
No full textVideo clips of mathematics lessons are used extensively in pre-service teacher education and continuing professional development activities. Given course time constraints, an opportunity to critique these videos is not always possible. Because of this, and because pre-service teachers make extensive use of material found during internet searches, much of it purporting to exemplify ‘good’ practice, we were interested to know what sense they make of such material. By encouraging pre-service teachers to reflect and comment on the practices being promoted in this way, we wanted to hear what they focused on, their initial views of the teaching and learning shown in the video, and how their views were formed and affected by engaging in discussion. Findings indicate that pre-service teachers’ responses to the material were dominated by their beliefs about mathematics, and that engaging in discussion enabled them to appreciate the interpretations of others
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Mitomycin C in highly myopic eyes - Author reply
No full textOphthalmology. 2005 Feb;112(2):208-18; discussion 219.
Mitomycin C modulation of corneal wound healing after photorefractive keratectomy in highly myopic eyes.
Gambato C, Ghirlando A, Moretto E, Busato F, Midena E.
SourceRefractive Surgery Service and Antimetabolite Therapy Research Unit, Department of Ophthalmology, University of Padova, Padova, Italy.
Abstract
PURPOSE: To evaluate the role of topical mitomycin C in corneal wound healing (CWH) after photorefractive keratectomy (PRK) in highly myopic eyes.
DESIGN: Prospective, double-masked, randomized clinical trial.
PARTICIPANTS: Seventy-two eyes of 36 patients affected by high (>7 diopters) myopia.
METHODS: In each patient, one eye was randomly assigned to PRK with intraoperative topical 0.02% mitomycin C application, and the fellow eye was treated with a placebo. Postoperatively, mitomycin C-treated eyes received artificial tears (3 times daily, tapered in 3 months), whereas the fellow eye was treated with fluorometholone sodium 2% and artificial tears (3 times daily, tapered in 3 months).
MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity, manifest refraction, and biomicroscopy. Contrast sensitivity was determined using the Pelli-Robson chart. Corneal confocal microscopy documented CWH.
RESULTS: Mean follow-up was 18 months (range, 12-36). No side effects or toxic effects were documented. At 12-month follow-up examination, UCVAs (logarithm of the minimum angle of resolution) were 0.4+/-0.48 and 0.5+/-0.53 (P = .03) in mitomycin C-treated eyes and corticosteroid-treated eyes, respectively. At 1 year, corneal haze developed in 20% of corticosteroid-treated eyes, versus 0% of mitomycin C-treated eyes. At 12, 24, and 36 months, corneal confocal microscopy showed activated keratocytes and extracellular matrix significantly more evident in untreated eyes (Ps = 0.004, 0.024, and 0.046, respectively).
CONCLUSION: Topical intraoperative application of 0.02% mitomycin C can reduce haze formation in highly myopic eyes undergoing PRK.
Comment in
Ophthalmology. 2006 Feb;113(2):357; author reply 357-8
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Preservice teachers’ expressed awarenesses: emerging threads of retro-spection of learning and pro-spection of teaching
No full textIn this paper, we report an enquiry into elementary preservice teachers’ learning, as they engage in doing mathematics for themselves. As a group of researchers working in elementary initial teacher education in English universities, we co-planned and taught sessions on growing pattern generalisation. Following the sessions, interviews of fifteen preservice teachers at two universities focused on their expressed awareness of their approach to the mathematical activity. Preservice teachers’ prospective planning and post-teaching evaluations of similar activities in their classrooms were also examined. We draw on aspects of enactivism and the notion of reflective ‘spection' in the context of teacher learning, tracing threads between preservice teachers’ retro-spection of learning and pro-spection of teaching. Our analysis indicates that increasing sensitivity to their own embodied processes of generalisation offers opportunities for novice teachers to respond deliberately, rather than to react impulsively, to different pedagogical possibilities. The paper contributes a new dimension to the discussion about the focus of novice elementary school teachers’ retrospective reflection by examining how deliberate retrospective analysis of doing mathematics, and not only of teaching actions, can develop awarenesses that underlie the growth of expertise in mathematics teaching. We argue that engaging preservice teachers in mathematics to support deliberate retrospective analysis of their mathematics learning and prospective consideration of the implications for teaching, can enable more critical pedagogical choices
A Multi-Language Comparison of Influences on Author Verification using Character N-Grams
No full textWe create a new multi-language corpus for author verification based on Wikipedia talkpages, and evaluate the influence that differences in topic and time have on character n-gram author profiles. Topic alignment between two texts is found to increase author verification precision, and an authors writing style is found to change over time, but not more significantly after 3 years than after 1 year.Information ArchitectureWISElectrical Engineering, Mathematics and Computer Scienc
- …
