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91.
Development of early math skill depends on a prerequisite level of cognitive development. Identification of specific cognitive skills that are important for math development may not only inform instructional approaches but also inform assessment approaches to identifying children with specific learning problems in math. This study investigated the specific cognitive correlates of math problem solving across early grade levels (1–4) while controlling for basic calculation skills. As expected, basic calculation skill was a significant predictor of math problem solving across the entire sample. However, the addition of cognitive measures almost doubled the variance explained (R2 = .61). Additionally, only select cognitive variables contributed to the prediction of math problem solving, and these variables change in importance as children develop higher‐level math skills. Results are discussed within a developmental model, which emphasizes the increasing importance of abstract code representations required in higher levels of math performance.  相似文献   
92.
In educational environments, monitoring persons' progress over time may help teachers to evaluate the effectiveness of their teaching procedures. Electronic learning environments are increasingly being used as part of formal education and resulting datasets can be used to understand and to improve the environment. This study presents longitudinal models based on the item response theory (IRT) for measuring persons' ability within and between study sessions in data from web-based learning environments. Two empirical examples are used to illustrate the presented models. Results show that by incorporating time spent within- and between-study sessions into an IRT model; one is able to track changes in ability of a population of persons or for groups of persons at any time of the learning process.  相似文献   
93.
Ageing anxiety is the expression of peoples' fear of ageing (Lynch, 2000 Lynch, S. M. (2000). Measurement and prediction of aging anxiety. Research on Aging, 22(5), 533.[Crossref], [Web of Science ®] [Google Scholar]). Despite greater longevity in the population, there is a lack of research into this aspect of life (Lasher &; Faulkender, 1993 Lasher, K. P., &; Faulkender, P. J. (1993). Measurement of aging anxiety: Development of the Anxiety about Aging Scale. The International Journal of Aging &; Human Development, 37(4), 247259.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]). This research explored fears of ageing across four dimensions: Fear of Old People, Physical Appearance, Psychological Concerns, and Fear of Losses. Three hundred and forty eight participants aged 18–88 participated in an online survey. Findings were: (a) men and women have different fears of ageing; (b) greater quality contact is related to less ageing anxiety; (c) poor health is related to greater ageing anxiety, (d) ageism, defined by Nelson (2005 Nelson, T. D. (2005). Ageism: Prejudice against our feared future self. Journal of Social Issues, 61(2), 207221.[Crossref], [Web of Science ®] [Google Scholar]) as prejudice toward ageing is positively correlated with ageing anxiety. The implications of these findings are that better quality contact and more positive attitudes toward ageing are associated with less ageing anxiety. As such, possible key target areas in developing appropriate interventions are provided, with hope to prepare adults of all ages for the inevitable—life is a terminal illness, so enjoy while you can.  相似文献   
94.
When educators consider ‘student behaviour’, they usually think about ‘problem behaviour’ such as disruption or defiance. This limited and limiting view of ‘student behaviour’ not only fails to acknowledge children as educational actors in a wider sense, but also narrowly positions educators as either in control or out of control of their classroom. Mainstream educational psychology’s responses to ‘challenging behaviour’ point educators to numerous ways to prevent its occurrence, through, for example, changing their disciplining approaches and techniques. However, much of the advice directed at improving student behaviour fails to interrogate the core notion of ‘student behaviour’ itself, as well as the conceptual baggage that it carries. The focus is squarely on eliminating ‘problem behaviour’ and often resorts to a pathologisation of students. Meanwhile, when considering ‘student behaviour’ through a Foucauldian post-structuralist optic, behaviour emerges as something highly complex – as spatialised, embodied action within/against governing discourses. In this opening up, it becomes both possible and critical to defamiliarise oneself with the categorisation of ‘challenging behaviour’ and to interrogate the discourses and subject positionings at play. In this paper, we pursue this task by asking: what happens with the notion of ‘behaviour’ if we change focus from ‘fixing problems’ to looking at the discursive constitution of ‘learner subjectivities’? What does it become possible to see, think, feel and do? In this exploration, we theorise ‘behaviour’ as learning and illustrate the constitution of ‘learner subjectivities’. Drawing on two case scenarios, we explore how children accomplish themselves as learners and how this accomplishment links the production of subjectivity and embodied action, and illustrate how ‘student/child behaviour’ appears significantly different to what mainstream educational psychology would have us see.  相似文献   
95.
Children's Literature in Education - This paper considers the Twilight novels alongside the Vampire Academy books, as young adult readers regularly invoke these series as touchstones...  相似文献   
96.
In recent years, there has been a strong push to transform STEM education at K-12 and collegiate levels to help students learn to think like scientists. One aspect of this transformation involves redesigning instruction and curricula around fundamental scientific ideas that serve as conceptual scaffolds students can use to build cohesive knowledge structures. In this study, we investigated how students use mass balance reasoning as a conceptual scaffold to gain a deeper understanding of how matter moves through biological systems. Our aim was to lay the groundwork for a mass balance learning progression in physiology. We drew on a general models framework from biology and a covariational reasoning framework from math education to interpret students' mass balance ideas. We used a constant comparative method to identify students' reasoning patterns from 73 interviews conducted with undergraduate biology students. We helped validate the reasoning patterns identified with >8000 written responses collected from students at multiple institutions. From our analyses, we identified two related progress variables that describe key elements of students' performances: the first describes how students identify and use matter flows in biology phenomena; the second characterizes how students use net rate-of-change to predict how matter accumulates in, or disperses from, a compartment. We also present a case study of how we used our emerging mass balance learning progression to inform instructional practices to support students' mass balance reasoning. Our progress variables describe one way students engage in three dimensional learning by showing how student performances associated with the practice of mathematical thinking reveal their understanding of the core concept of matter flows as governed by the crosscutting concept of matter conservation. Though our work is situated in physiology, it extends previous work in climate change education and is applicable to other scientific fields, such as physics, engineering, and geochemistry.  相似文献   
97.
This article examines how we use mobile telephony to maintain our physically and socially closest social circle. The analysis is based on traffic data gathered from Norway using approximately 24 million calls and texts made by private individuals. Previous research has shown that our temporal and spatial movement is highly predictable and that the majority of calls and text messages are sent to only four to six different persons. This article extends this research by examining both tie strength and the distance between the interlocutors in urban and rural settings. The findings show that even as information and communication technologies (ICTs) potentially put the world at our fingertips, the mobile phone is an instrument of a more limited geographical and social sphere. Approximately two-thirds of our calls/texts go to strong ties that are within a 25-km radius.  相似文献   
98.
We digitized three years of Dutch election manifestos annotated by the Dutch political scientist Isaac Lipschits. We used these data to train a classifier that can automatically label new, unseen election manifestos with themes. Having the manifestos in a uniform XML format with all paragraphs annotated with their themes has advantages for both electronic publishing of the data and diachronic comparative data analysis. The data that we created will be disclosed to the public through a search interface. This means that it will be possible to query the data and filter them on themes and parties. We optimized the Lipschits classifier on the task of classifying election manifestos using models trained on earlier years. We built a classifier that is suited for classifying election manifestos from 2002 onwards using the data from the 1980s and 1990s. We evaluated the results by having a domain expert manually assess a sample of the classified data. We found that our automatic classifier obtains the same precision as a human classifier on unseen data. Its recall could be improved by extending the set of themes with newly emerged themes. Thus when using old political texts to classify new texts, work is needed to link and expand the set of themes to newer topics.  相似文献   
99.

Introduction:

Additional nucleotide substitutions in the 3′-untranslated region of prothrombin gene could explain some thrombotic events and also adverse pregnancy outcomes. We describe the first case of a homozygous 20209C>T mutation as the cause of deep vein thrombosis in a Spanish patient.

Case and methods:

The 56-year-old male patient with a partial tear of the Achilles tendon developed calf (tibial) deep vein thrombosis after immobilization and was treated with an anticoagulant. To determine if the deep vein thrombosis was of genetic origin, a peripheral blood DNA sample was analysed for the presence of the three most frequent mutations associated with thrombotic events: factor V Leiden (1691G>A), prothrombin (20210G>A) and methylene tetrahydrofolate reductase (677C>T). The presence or absence of the normal allele of prothrombin could not be determined using the PTH-FV-MTHFR StripAssay (Vienna Lab).

Results:

Comprehensive analysis showed that the patient had a variant interfering with the polymerase chain reaction product, we sequenced the entire prothrombin gene and found that the patient had a homozygous C>T mutation at position 20209; this interfered with the polymerase chain reaction product, which needs a C at this position to be able to bind to the wild-type probe present in the test strip.

Conclusion:

The homozygous 20209C>T mutation and the presence of the mutation 677C>T in heterozygosity explained the patient’s deep vein thrombosis because the combination of mutations would increase the risk of thrombosis. Suitable genetic counselling should be provided to the patient and first-degree relatives as it important to detect prothrombin gene variants that could increase risk for thrombotic events.  相似文献   
100.
This paper advances the ongoing discussion of methods for predicting movie box office revenues with two contributions to the methodology and an out-of-sample test of the model. The first innovation is the development of a two-stage model using publicly available pre-release indicators to predict (1) initial week and (2) subsequent run box office revenues. To incorporate the experience-good nature of movies, the second stage is estimated by incorporating a proxy variable for box office success during the first week relative to predicted first week success. The second contribution is an empirical test of De Vany and Walls’ (J Econ Dyn Control 28:1035–1057, 2004) finding that the distribution of movie revenues has “heavy tails” and follows a non-Gaussian stable distribution with infinite variance. We estimate the two-stage model of a movie’s box office success on all general release movies in 1 year with both the Gaussian and stable distribution with heavy tails and infinite variance and find no evidence for the stable distribution in either stage of the estimation. This two-stage model is validated by comparing all general release movies in 3 future years (out-of-sample data) to the model’s predictions.  相似文献   
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