bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional magnetic resonance imaging: basic principles of and application to developmental science
Authors: Casey B.J. , Davidson Matthew , Rosen Bruce 
Published: March 2003

AbstractFunctional magnetic resonance imaging (fMRI) has quickly become the preferred technique for imaging normal brain activity, especially in the typically developing child. This technique takes advantage of specific magnetic properties and physiological processes to generate images of brain activity. These images can be interpreted as a function of group or individual based differences to explore developmental patterns and/or cognitive abilities. In this paper we present an overview of the basic principles of fMRI and a discussion of what is currently known about the physiological bases of the resulting signal. We also report findings from developmental fMRI studies that examine the development of cognitive and neural systems underlying attention and memory. Behavioral performance and age‐related neural changes are examined independently in an attempt to disentangle developmental differences from individual variability in performance.
Ageism: A Factor in the Nutritional Vulnerability of Older People?
Authors: Peachey Karen 
Published: March 2003

Unlike other population groups, the rights, needs and contributions of older people in developing countries are not well understood. With the absence of information about how to assess the nutritional status and vulnerability of older people, HelpAge International joined forces with the London School of Hygiene and Tropical Medicine in the early 1990s to launch a research programme. Seven years later some of the basic questions can now be answered but there remains much more to do.Although older people are increasingly acknowledged as a vulnerable group in emergencies, NGO responses often fail to meet their needs. The question is whether there are real difficulties in service adaptation or whether ageism is one of the greatest barriers to the provision of appropriate services for older people.
Rapid Assessment of Population Size by Area Sampling in Disaster Situations
Authors: Brown Vincent , Jacquier Guy , Coulombier Denis , Balandine Serge , Belanger François , Legros Dominique 
Published: March 2003

In the initial phase of a complex emergency, an immediate population size assessment method, based on area sampling, is vital to provide relief workers with a rapid population estimate in refugee camps. In the past decade, the method has been progressively improved; six examples are presented in this paper and questions raised about its statistical validity as well as important issues for further research.There are two stages. The first is to map the camp by registering all of its co‐ordinates. In the second stage, the total camp population is estimated by counting the population living in a limited number of square blocks of known surface area, and by extrapolating average population calculated per block to the total camp surface.In six camps selected in Asia and Africa, between 1992 and 1994, population figures were estimated within one to two days. After measuring all external limits, surfaces were calculated and ranged between 121,300 and 2,770,000 square metres. In five camps, the mean average population per square was obtained using blocks 25 by 25 metres (625m2), and for another camp with blocks 100 by 100m2 . In three camps, different population density zones were defined. Total camp populations obtained were 16,800 to 113,600.Although this method is a valuable public health tool in emergency situations, it has several limitations. Issues related to population density and number and size of blocks to be selected require further research for the method to be better validated.
Does the Commercialization of Voluntary Organizations ‘Crowd out’ Voluntary Work?
Authors: Enjolras Bernard 
Published: March 2003

This article examines the relationship among voluntary labour supply and commercial income for Norwegian sport voluntary organizations. Empirical results using cross–sectional data on voluntary sport organizations in Norway and on their members show a decrease in voluntary work from an increase in commercial income. Voluntary work and commercial income appear as substitutable resources. Nevertheless, the results have to be differentiated according to the professional situation of the volunteers.A crowding out effect between voluntary work and commercial resources is at play for non–professionally active individuals whereas professionally active individuals seem to be indifferent to the level of commercial resources in deciding whether to volunteer or not.
Reefer Madness: Legal & Moral Issues Surrounding the Medical Prescription of Marijuana
Authors: Barnes R. Eric 
Published: March 2003

California, Arizona, and several other states have recently legalized medical marijuana. My goal in this paper is to demonstrate that even if one grants the opponents of legalization many of their contentious assumptions, the federal government is still obligated to take several specific steps toward the legalization of medical marijuana. I defend this claim against a variety of objections, including the claims: that marijuana is unsafe, that marijuana cannot be adequately tested or produced as a drug, that the availability of synthetic THC makes marijuana superfluous, and especially that legalizing medical marijuana will increase recreational use by ‘sending the wrong message ’. I then go on to argue that given the intransigent position of the federal government on this issue, state governments are justified in unilaterally legalizing medical marijuana as an act of civil disobedience.A large portion of this paper consists of an extensive response to the objection that legalizing medical marijuana will ‘send the wrong message ’– which I take to be the primary impediment to legalization. This objection basically claims that the consequences of withholding legalization (especially preventing increased recreational use) are superior to those of legalizing medical marijuana. I argue that legalization is justified even if one were to grant both that the harms of legalization outweighed its benefits and that utilitarianism is true. This requires a subtle and somewhat extended discussion of utilitarian moral and political theory.
The Doctor‐Patient Relationship: A Survey of Attitudes and Practices of Doctors in Singapore
Authors: Chan David , Goh Lee Gan 
Published: March 2003

This article reports the results of a survey, by mailed questionnaire, of the attitudes, values and practices of doctors in Singapore with respect to the doctor‐patient relationship. Questionnaires were sent to a random sample of 475 doctors (261 general practitioners and 214 medical specialists), out of which 249 (52.4%) valid responses were completed and returned. The survey is the first of its kind in Singapore. Questions were framed around issues of medical paternalism, consent and patient autonomy. As the doctors were exposed to Western ethical concepts in their training, we were not surprised to find that they would mostly allow patients some say in decision‐making and keep patients reasonably informed. In respecting patient autonomy, they would usually seek to influence patient choice by persuasion. However, the residual ‘Asian‐ness’ of doctors in Singapore gives rise to some inconsistencies between values and practices. Many doctors still believe that a number of their patients are incapable of rational choice. There is some lack of openness in telling patients the whole truth. When patients choose to refuse treatment, many doctors are prepared to involve family members in making a consensus decision.Doctors were also asked how they made ethical judgements in the face of dilemmas, and how they would like disputes with patients to be resolved. By and large, the doctors prefer to make their own judgements rather than to rely on rules. They also wish to keep the law courts out of disputes with patients, preferring less public ways of settling disputes.
A study of curriculum development in a new special school
Authors: Maddison Anne 
Published: March 2003

Anne Maddison is deputy headteacher, with responsibility for curriculum, at the Milestone School, a special school created recently after the amalgamation of three smaller schools. In this article, she describes the development of an outcomes‐based curriculum for pupils with a range of learning difficulties aged from two to 16 years. Anne Maddison sets out the rationale for her work in the context of a need to promote shared approaches to teaching and learning at this newly formed school.The curriculum development project described here was evaluated using questionnaires, interviews and the analysis of documents and practice as part of a case study in school‐based enquiry. Anne Maddison used the outcomes of these processes as part of her Doctor of Education (EdD): Educational Leadership course at Lincoln University.Since this article was written, the Milestone School has undergone its first Ofsted inspection. The report noted that teaching at the school is ‘of very high quality’ and the curriculum ‘is very good’. Inspectors noted that ‘the planning of schemes of work, which are being developed with different subjects being focused on each year, is exemplary, with clear outcomes for pupils of different abilities’. While Anne Maddison’s article details the experience of one school, her analysis may be of interest to other school managers, teachers, governors or advisers who are seeking to promote the development of a more inclusive curriculum.
Maximising the language and learning link in computer learning environments
Authors: McLoughlin Catherine , Oliver Ron 
Published: March 2003

In studies on the implementation and educational uses of computers there are reports of changes in students' behaviour as a result of working with computers (Rowe, 1993; Crook, 1994). Social, collaborative and dialogic exchanges have been observed as students engage in tasks around computers. This research provides evidence that the computer is a social facilitator in the sense that it provides opportunities for collaboration, group work and interaction which fosters cognitive change (Wild, 1995).This article recognises the social role of the computer, and supports the view that computers can be used to facilitate learning through language. There is growing awareness that if we are to realise the full potential of computers in education, consideration must be given to their role as catalysts in the learning process, rather than technological tools (Hawkridge, 1990). Computer assisted learning has progressed through many phases, and through investigation of underlying theoretical frameworks it is possible to recognise the change of focus from individual accounts of learning to social perspectives.Theoretical frameworks which emphasise the social dimensions of learning (Vygotsky, 1978) legitimise the link between computers, language use and learning and indicate that computers must be integrated into the social life of classrooms if their pedagogical benefits are to be realised.
Cultural Issues in the Design of Technology‐Enhanced Learning Systems
Authors: Chen Ai‐Yen , Mashhadi Azam , Ang Daniel , Harkrider Nancy 
Published: March 2003

The pervasive influence of culture should be regarded as a significant concern in the design of technology‐enhanced learning systems. In fact, it has been included as one of the five essential foundations of effective student‐centred learning environments (Chen and Mashhadi, 1998). The other foundations are psychological, pedagogical, technological, and pragmatic. This article will focus mainly on the cultural and pedagogical considerations in the design of student‐centred learning systems with particular reference to three cases in Singapore. The experiences will illustrate some of the challenges and problems in designing and implementing learning systems in three different contexts: local‐institutional, trans‐institutional, and global. Some of the instructional design issues include those articulated by Collins (1997) in his consideration for building a constructivist learning environment. They are related to learning goals such as thoughtfulness vs memorization, whole tasks vs component skills tasks, breadth vs depth of knowledge, diverse vs uniform expertise, understanding vs access, cognitive vs physical fidelity. Two other issues also merit consideration, namely authentic vs abstract problem solving, and multi‐directional and multimedia communication vs direct one‐way communication.In the design of three Singapore‐based learning systems, the cultural assumptions of prevailing beliefs about education, the values of Singaporean multicultural society, and the role of individuals in society were considered. Two of the systems were designed for student teachers and the third was meant for students collaborating on projects across schools and nations. Lessons learned from the three experiences will be discussed with a view to making recommendations to other educators, instructional designers and policy makers in their decisions regarding their use of technology‐enhanced learning systems to nurture a more independent, thoughtful, resourceful, creative and responsible generation of citizens.
Portable computers for teachers and support services working with pupils with Special Educational Needs: An evaluation of the 1999 United Kingdom Department for Education and Employment scheme
Authors: Lewis Ann , Neill Sean 
Published: March 2003

This study arose from the distribution of portable computers (“portables”) to special educational needs coordinators and support services by the Department for Education and Employment (DfEE) through Standards Grant 36 in mid 1999. The study comprised two successive questionnaires. The aim of the surveys was to elicit the benefits of portables in relation to the special educational needs coordinator/support service roles as well as to evaluate this process of distributing resources.Questionnaire A to local education authorities (LEAs) was returned by 96 LEAs (a 64% return rate). There were 778 returns of questionnaire B from recipients of portables and 405 returns from the matched group of non‐recipients.Overall the distribution of portables under this grant was well‐regarded by LEA personnel, particularly in the smaller authorities, with reservations relating mainly to the lack of time to administer the scheme. The guidance from the DfEE was regarded as helpful with inherent (valued) flexibility. Amount and level of training appeared to have varied greatly across LEAs but where training had been relatively substantial there was evidence of its impact on teachers' reported use of the portables. The scheme was welcomed by school and, particularly, support service staff. However all recipient groups tended to reflect some disappointment with what the portable provided in practice.Three particular aspects are discussed in more detail. First, in relation to time and workload issues, it was reported that teachers were spending considerable “non work” time in learning to make good use of the portables. Second, there were considerable training needs for teachers and others, spanning a wide range of levels. Third, the position of support service staff warranted more attention as their apparently comparatively disadvantageous position has implications for wider changes concerning centralised LEA, as opposed to school‐based, resources.
Early Reading Development in Children at Family Risk for Dyslexia
Authors: Pennington Bruce F. , Lefly Dianne L. 
Published: March 2003

In a 3‐year longitudinal study, middle‐ to upper‐middle‐class preschool children at high family risk (HR group, N= 67) and low family risk (LR group, N= 57) for dyslexia (or reading disability, RD), were evaluated yearly from before kindergarten to the end of second grade. Both phonological processing and literacy skills were tested at each of four time points. Consistent with the well‐known familiarity of RD, 34% of the HR group compared with 6% of the LR group became RD. Participants who became RD showed deficits in both implicit and explicit phonological processing skills at all four time points, clearly indicating a broader phonological deficit than is often found at older ages. The predictors of literacy skill did not vary by risk group. Both risk groups underwent a similar developmental shift from letter‐name knowledge to phoneme awareness as the main predictor of later literacy skill. This shift, however, occurred 2 years later in the HR group. Familial risk was continuous rather than discrete because HR children who did not become RD performed worse than LR non‐RD children on some phonological and literacy measures. Finally, later RD could be predicted with moderate accuracy at age 5 years, with the strongest predictor being letter‐name knowledge.
The Influence of Group Size on Children's Competitive Behavior
Authors: Benenson Joyce F. , Nicholson Catherine , Waite Angela , Roy Rosanne , Simpson Anna 
Published: March 2003

The present research was designed to test the hypothesis that children would compete more in tetrads than in dyads. Twenty‐two pairs of male and 14 pairs of female target children (N= 72) played a competitive game in both tetrads and dyads. Consistent with the hypothesis, male target children competed more in tetrads than in dyads. This hypothesis was not supported for females, however. Analyses of the dynamics of tetrads and dyads further demonstrated that based on a global measure of smiling, the emotional atmosphere was less positive in tetrads than in dyads. The causes and consequences of interaction in different sized social groups are discussed.
Learning Words from Knowledgeable versus Ignorant Speakers: Links Between Preschoolers' Theory of Mind and Semantic Development
Authors: Sabbagh Mark A. , Baldwin Dare A. 
Published: March 2003

Two studies addressed whether children consider speakers' knowledge states when establishing initial word‐referent links. In Study 1, forty‐eight 3‐ and 4‐year‐olds were taught two novel words by a speaker who expressed either knowledge or ignorance about the words' referents. Children showed better word learning when the speaker was knowledgeable. In Study 2, forty‐eight 3‐ and 4‐year‐olds were taught two novel words by a speaker who expressed uncertainty about their referents. Whether the uncertainty truly reflected ignorance, however, differed across conditions. In one condition, the speaker said he made the object himself and thus, he was knowledgeable. In the other condition, the speaker stated that the object was made by a friend and thus, expressed ignorance about it. Four‐year‐olds learned better in the speaker‐made than in the friend‐made condition; 3‐year‐olds, however, showed relatively poor learning in both conditions. These findings suggest that theory‐of‐mind developments impact word learning.
Dithered Color Quantization
Authors: Buhmann J.M. , Fellner D.W. , Held M. , Ketterer J. , Puzicha J. 
Published: March 2003

Image quantization and digital halftoning are fundamental problems in computer graphics, which arise when displaying high‐color images on non‐truecolor devices. Both steps are generally performed sequentially and, in most cases, independent of each other. Color quantization with a pixel‐wise defined distortion measure and the dithering process with its local neighborhood optimize different quality criteria or, frequently, follow a heuristic without reference to any quality measure.In this paper we propose a new method to simultaneously quantize and dither color images. The method is based on a rigorous cost‐function approach which optimizes a quality criterion derived from a generic model of human perception. A highly efficient algorithm for optimization based on a multiscale method is developed for the dithered color quantization cost function. The quality criterion and the optimization algorithms are evaluated on a representative set of artificial and real‐world images as well as on a collection of icons. A significant image quality improvement is observed compared to standard color reduction approaches.
Wavelet Radiative Transfer and Surface Interaction
Authors: Lewis Robert R. , Fournier Alain 
Published: March 2003

Recently, there has been considerable interest in the representation of radiance in terms of wavelet basis functions. We will present a coordinate system called Nusselt coordinates which, when combined with wavelets, considerably simplifies computation of radiative transport and surface interaction. It also provides straightforward computation of the physical quantities involved.We show how to construct a discrete representation of the radiative transport operator Τ involving inner products of smoothing functions, discuss the possible numerical integration techniques, and present an application. We also show how surface interaction can be represented as a kind of matrix product of the wavelet projections of an incident radiance and a bidirectional reflectance distribution function (BRDF).
A Survey of 3D Solid Reconstruction from 2D Projection Line Drawings
Authors: Wang Weidong , Grinstein Georges G. 
Published: March 2003

AbstractThe reconstruction of a 3D object from its 2D projection(s) and its corresponding problem of 3D object recognition are two of the important research areas in the field of computer vision and artificial intelligence. Reconstruction involves determining the geometric and topological relationship of an object's atomic parts whereas recognition involves identifying an object by some form of template matching. Nagendra and Gujar1 gave a survey of several papers on reconstruction of 3D object from its 2D views. In this paper we present a taxonomy of 3D object reconstruction from 2D projection line drawings. We base the classification on the number of 2D views of the 3D solid object, the degree of user interaction necessary for correct reconstruction, and the internal representation used in the reconstruction process. We discuss the basic issues associated with this problem, review the relevant literature and present topics for future research.
A Theoretical Framework for Physically Based Rendering
Authors: Lafortune Eric P. , Willems Yves D. 
Published: March 2003

AbstractIn this paper we introduce the concept of the global reflection distribution function which allows concise formulation of the global illumination problem. Unlike previous formulations it is not geared towards any specific algorithm. As an example of its versatility we derive a Monte Carlo rendering algorithm that seamlessly integrates the ideas of shooting and gathering power to create photorealistic images.
The Mesh Propagation Algorithm for Isosurface Construction
Authors: Howic C.T. , Blake E.H. 
Published: March 2003

AbstractA new algorithm, Mesh Propagation, is presented for the generation of isosurfaces from three‐dimensional discrete data sets. While producing the same surface mesh as that generated by a corrected Marching Cubes algorithm, its characteristic is that it constructs an isosurface using connected strips of dynamically triangulated polygons. This compact data structure speeds up surface construction and reduces surface storage requirements. The surface can also be displayed more quickly, particularly where there is hardware support for rendering triangle strips.With engineering as well as medical imaging applications in mind, the algorithm can be used with both irregular and rectilinear grids of data, the primitive volume elements need not be hexahedral only, and volumes of heterogeneous polyhedral elements are supported without traversal complications.The algorithm propagates through the cells in the grid and uses the same lookup table topologies as Marching Cubes to determine patches of surface‐element intersection; additional tables are used for non‐hexahedral elements. The surface patches are dynamically coded into triangle strips which are then concatenated and linked to construct the surface. The data structures used for propagating through the volume overcome the topological ambiguities associated with table‐based methods of surface construction and no holes are generated in the final mesh.