The goal of this paper is to explore qualities of mathematical imagination in light of a classroom episode. It is based on
the analysis of a classroom interaction in a high school Algebra class. We examine a sequence of nine utterances enacted by
one of the students whom we call Carlene. Through these utterances Carlene illustrates, in our view, two phenomena: (1) juxtaposing
displacements, and (2) articulating necessary cases. The discussion elaborates on the significance of these phenomena and
draws relationships with the perspectives of embodied cognition and intersubjectivity. 相似文献
The association between fluid intelligence and inter-individual differences was investigated using multilevel growth curve modeling applied to data measuring intra-individual improvement on math achievement tests. A sample of 166 students (88 boys and 78 girls), ranging in age from 11 to 14 (M = 12.3, SD = 0.64), was tested. These individuals took four math achievement tests, which were vertically equated via Item Response Theory, at the beginning and end of the seventh and eighth grade. The cognitive abilities studied were Numerical Reasoning, Abstract Reasoning, Verbal Reasoning, and Spatial Reasoning (as measured by the Differential Reasoning Test). The general cognitive factor was significantly associated with the parameters of initial level (intercept) and rate of change (slope). A high level of intelligence was associated with higher initial scores, as well as a steeper rise in math scores across the two years. 相似文献
The role of information and communication technologies (ICT) in education is well recognised – learning environments where the ICT features included are being proposed for many years now. The Web Geometry Laboratory (WGL) innovates in proposing a blended learning, collaborative and adaptive learning Web-environment for geometry. It integrates a well-known dynamic geometry system providing an adaptive environment where face-to-face activities can be combined with computer-mediated activities, in a collaborative or stand-alone, synchronous or asynchronous, classroom or homework way. The WGL collaborative environment allows each student to capitalise on one another's resources and skills. Its adaptive module gives to each teacher the ability to assess the geometric level of each student, allowing the teacher to build the individual profile and/or learning paths. In this paper we begin describing what are the goals that support the development of such an environment, the goals that support our beliefs in the usefulness of such an environment for the teaching and learning of geometry, after which we describe the environment and the case studies already conducted. 相似文献
Immigration is a growing social dynamic in many countries, eliciting a variety of different responses. Proponents of immigration note how the influx of new people into the United States (US) has enhanced the workforce and brought cultural enrichment; others have attributed to immigrants, particularly undocumented, a rise in crime and strains on social services. Consequently, immigrants often contend with discrimination and other unique stressors that increase the likelihood that immigration will be a traumatizing experience. Because scholarly focus on the impact of immigration upon psychological wellbeing typically highlights individual experiences, there is limited attention on the impact on immigrant families, particularly mixed-status families comprised of immigrant parents and children who are US citizens by birth. There is also limited attention on immigrant dynamics in the Southern US. This qualitative, thematic analysis explores the experiences of 71 pairs of Latinx immigrant mothers and their US citizen children, living in the Southern US, utilizing the lens of intergenerational transmission of trauma. Using narrative data taken from trauma assessment instruments, the authors identified the most prevalent themes shared by the mothers and their children as crime victimization, deportation, threats to family health, sexual abuse, and marital conflict.
Due to its fundamental role for the consolidation of Maxwell’s equations, the displacement current is one of the most important topics of any introductory course on electromagnetism. Moreover, this episode is widely used by historians and philosophers of science as a case study to investigate several issues (e.g. the theory–experiment relationship). Despite the consensus among physics educators concerning the relevance of the topic, there are many possible ways to interpret and justify the need for the displacement current term. With the goal of understanding the didactical transposition of this topic more deeply, we investigate three of its domains: (1) The historical development of Maxwell’s reasoning; (2) Different approaches to justify the term insertion in physics textbooks; and (3) Four lectures devoted to introduce the topic in undergraduate level given by four different professors. By reflecting on the differences between these three domains, significant evidence for the knowledge transformation caused by the didactization of this episode is provided. The main purpose of this comparative analysis is to assist physics educators in developing an epistemological surveillance regarding the teaching and learning of the displacement current. 相似文献
The Yarowsky bootstrapping algorithm resolves the homograph-level word sense disambiguation (WSD) problem, which is the sense granularity level required for real natural language processing (NLP) applications. At the same time it resolves the knowledge acquisition bottleneck problem affecting most WSD algorithms and can be easily applied to foreign language corpora. However, this paper shows that the Yarowsky algorithm is significantly less accurate when applied to domain fluctuating, real corpora. This paper also introduces a new bootstrapping methodology that performs much better when applied to these corpora. The accuracy achieved in non-domain fluctuating corpora is not reached due to inherent domain fluctuation ambiguities. 相似文献
There are limited data describing mobility interventions provided to patients with femoral catheters. The purpose of this study was to examine the incidence of femoral catheter related adverse effects during physical therapy (PT) sessions in a cardiovascular intensive care unit (ICU).
Methods
This was a prospective, observational study and included patients with at least one femoral catheter. Data were collected after each PT session.
Results
There were 77 subjects with a total of 92 femoral catheters (50 arterial, 15 central venous, and 27 dialysis) treated. A total of 210 separate PT sessions occurred with 630 mobility activities including sitting on side of bed, standing at the bedside, transfers to stretcher chair or regular chair, and walking. There were no catheter related mechanical or thrombotic complications during any of the PT sessions.
Conclusions
Physical therapy sessions, including standing and walking were feasible and safe in cardiovascular ICU patients with femoral catheters who met the criteria for mobility interventions. The results from this study support the hypothesis that early mobilization in patients with femoral catheters is important to minimize functional decline and provide evidence that the presence of femoral catheters alone should not be a reason to limit progressive mobility interventions.Key Words: physical therapy, ICU, early mobilization, femoral catheter相似文献
This paper is a case study of how a high school student, whom we call Karen, used a computer-based tool, the Contour Analyzer, to create graphs of height vs. distance and slope vs. distance for a flat board that she positioned with different slants and orientations. With the Contour Analyzer one can generate, on a computer screen, graphs representing functions of height and slope vs. distance corresponding to a line traced along the surface of a real object. Karen was interviewed for three one-hour sessions in an individual teaching experiment. In this paper, our focus is on how Karen came to recognize by visual inspection the mathematical behavior of the slope vs. distance function corresponding to contours traced on a flat board. Karen strove to organize her visual experience by distinguishing which aspects of the board are to be noticed and which ones are to be ignored, as well as by determining the point of view that one should adopt in order to see the variation of slope along an object. We have found it inspiring to use Winnicott's (1971) ideas about transitional objects to examine the role of the graphing instrument for Karen. This theoretical background helped us to articulate a perspective on mathematical visualization that goes beyond the dualism between internal and external representations frequently assumed in the literature, and focuses on the lived-in space that Karen experienced which encompassed at once physical attributes of the tool and human possibilities of action.This revised version was published online in September 2005 with corrections to the Cover Date. 相似文献
AbstractNumerous organizations work to provide humanitarian aid to undocumented migrants along the US-Mexico border—from running shelters in Mexico to placing water on migratory trails. Resistance to information-sharing between organizations (and to the public), especially through technologically mediated means, is common. However, some organizers and volunteers work across organizational boundaries and share information informally. Information secrecy is often justified by concerns that law enforcement authorities or anti-immigration activists might gain access to information, allowing them to harm, detain or remove migrants, or interfere with humanitarian work. The choices made about the collection and (non)disclosure of information are manifestations of what we call “liminal” information practices: such behaviors are unique to humanitarian volunteers working in the gray, ethical area between law enforcement and humanitarian values and action, and they are guided by the information politics at play within this context. 相似文献