bluuebunny/crossref_metadata_2025 huggingface dataset:
Band anticrossing in diluted AlxGa1−xAs1−yNy (x⩽0.37,y⩽0.04)
Authors: Procz S. , Fiederle M. , Kunzer M. , Köhler K. , Wagner J.
Published: April 2008

We show that the conduction band structure of dilute AlxGa1−xAs1−yNy with x⩽0.37 and y⩽0.04 can be described consistently by the experimentally motivated band anticrossing model. The interband transition energies E−, E−+Δ0, and E+ have been derived from a full line shape fit to photomodulated reflectance (PR) spectra recorded at room temperature. The PR data were taken (a) from a series of Al0.06Ga0.94As1−yNy samples with y⩽0.04 and (b) from a set of AlxGa1−xAs0.99N0.01 layers with x⩽0.37. The latter series covers the range of Al concentrations where the AlxGa1−xAs band gap energy EM is expected to cross the nitrogen-induced energy level EN. The resulting nitrogen- and Al-concentration dependent interband transition energies are described by the band anticrossing model using a matrix element for the coupling between the nitrogen-induced states and the extend lowest conduction band states of CMN=2.32eV and a nitrogen level energy EN=(1.625+0.069x)eV, the latter measured with respect to the GaAs valence band edge.
Maxima of Neumann eigenfunctions
Authors: Donnelly Harold
Published: April 2008

We formulate and prove a modified version of the hot spots conjecture.
Lateral and longitudinal mode pattern of broad ridge 405nm (Al, In)GaN laser diodes
Authors: Braun H. , Solowan H.-M. , Scholz D. , Meyer T. , Schwarz U. T. , Brüninghoff S. , Lell A. , Strauß U.
Published: April 2008

The lateral mode profile of pulsed broad ridge 405nm (Al, In)GaN laser diodes grown on GaN and SiC substrates, respectively, is investigated by temporal and spectral resolved scanning near-field optical microscopy. During the first microsecond of the pulse, we observe changes both in the spatial mode profile and in the spectral regime caused by thermal and carrier induced modification of the waveguide refractive index, before stable filaments build up. In quasi-cw operation, a correlation between the lateral mode profile and the corresponding spatial resolved longitudinal mode pattern can be found. The results show that different filaments have different effective refractive indices and thus build up separate longitudinal mode combs.
Applied and residual stresses in brittle cylindrical multilayered composites
Authors: Ambrožič Milan , Kosmač Tomaž
Published: April 2008

We have made a theoretical study of the stress state in brittle multilayered composites with variable numbers, compositions, and thicknesses of concentric cylindrical layers. We used the linear theory of elasticity to calculate the stresses in the materials as they were subjected to a three-point bending test, including the thermal residual stresses that result from the fabrication process. As an example of the application of our model, we studied alumina/zirconia ceramic composites, wherein we indicated the way of optimizing individual layer compositions and thicknesses to get the highest composite strength. When the thicknesses of the layers are optimized for a given composition, more than one layer tends to be simultaneously damaged at the threshold force.
Low residual doping level in homoepitaxially grown ZnO layers
Authors: Robin I. C. , Ribeaud A. , Brochen S. , Feuillet G. , Ferret P. , Mariette H. , Ehrentraut D. , Fukuda T.
Published: April 2008

ZnO homoepitaxial growth is shown to change the luminescent properties of ZnO in a substantial way. Temperature dependent (4–300K) photoluminescence properties of the films grown by metal organic vapor phase epitaxy or by liquid phase epitaxy are compared to those of the hydrothermal ZnO substrate used for the growth. The intensity ratio between the free exciton and the donor bound exciton strongly increases, following homoepitaxial growth. The activation energy of the band edge emission intensity also increases from 13meV, which corresponds to the donor bound exciton localization energy, up to a value of 60meV, which corresponds to the free exciton binding energy. This indicates that homoepitaxial growth favors free exciton emission instead of donor bound exciton emission.
Influence of biotin supplementation on hoof growth and integrity in long-fed F1 Wagyu/Black Angus feedlot steers of known genotype
Authors: Lawrence R. J. , Elliott R. , Norton B. W. , Thoefner M. B. , Loxton I. , Webber G.
Published: April 2008

Biotin was supplemented at three levels (0, 10 and 20 mg/steer.day) to 108 F1 Wagyu/Black Angus steers of known genotype, which were fed a wheat-based ration, to evaluate the effect on hoof growth, wear and integrity within feedlot pens. One hundred and eight steers of known sire lines were assigned to three biotin treatments (0, 10 and 20 mg/steer.day) with each treatment replicated four times using an unfasted liveweight of 410.5kg (s.e. ± 2.27, s.d. ± 24.41). A subset of 36 steers was randomly selected for monitoring of hoof growth on seven occasions, over a period of 301 days. Front hooves from selected steers within turn-off group were collected at the abattoir and investigated for hoof integrity through claw lesions, white line width and dry matter of both white line and hoof. Hoof growth rates over time remained relatively consistent. In contrast, hoof wear rates increased (P < 0.001) in association with rainfall and exceeded rates of hoof growth. Biotin supplementation did not affect (P > 0.05) hoof growth or wear. Examination of collected hooves revealed lesions present on both lateral and medial claws. Biotin supplementation had no effect (P > 0.05) on lesion number, white line width of the lateral and medial claws, or hoof and white line dry matter of the medial claw. In contrast, Grandsire had an effect on total hoof length at measurement periods 0, 167, 251 and 301 (P < 0.05), and also on white line width of both lateral (P = 0.015) and medial (P = 0.002) claws. Rainfall and related increase in pen moisture weakened hoof integrity by increasing hoof moisture content and hoof wear. Genotype appears to play a role in hoof integrity.
Effect of surface applied glycine betaine on herbage production and quality of perennial ryegrass - white clover pastures
Authors: Lee J. M. , Elborough K. , Catto W. D. , Donaghy D. J. , Roche J. R.
Published: April 2008

Osmoprotectants have been reported to reduce the detrimental effects of various environmental stresses in many different plant species. However, there is little research available concerning pasture species. Two experiments were undertaken with the aim of quantifying the effect of surface applications of exogenous glycine betaine (GB) on herbage production and quality of perennial ryegrass (Lolium perenne L.)–white clover (Trifolium repens L.) pastures during periods of moisture stress and cold temperatures over 2 years. Pastures fertilised with GB were compared with unfertilised pastures and pastures fertilised with nitrogen (N). Rates of 0.5, 1.0 and 1.5 kg GB/ha.defoliation were applied in experiment 1 and 5 kg GB/ha.defoliation was applied in experiment 2. Surface applications of GB did not significantly affect herbage production relative to unfertilised pastures; herbage yields averaged 12 248 and 12 693 kg DM/ha over 11 months in experiment 1, and 7253 and 7177 kg DM/ha over 6 months during summer and autumn in experiment 2, for the unfertilised control and GB, respectively. During both experiments, herbage quality parameters were not affected by GB application, although the proportion of white clover in the sward between summer and winter during experiment 1 was greater (P < 0.01) in plots treated with GB than in untreated plots. Application of N fertiliser increased (P < 0.001) herbage production, but did not consistently affect herbage quality. The failure of surface applications of exogenous GB to improve the herbage production or quality of perennial ryegrass–white clover pastures suggests that it is not an appropriate method to enhance plant tolerance to environmental stress at the concentrations applied in these studies.
The Information-Capacity of the Human Motor-System in Pursuit Tracking
Authors: Crossman E. R. F. W.
Published: April 2008

Human performance at a typical pursuit tracking task has been analysed by information theory. Without preview of the course, the channel-capacity was found to be about 4 bits per sec. With preview performance ceased to be perfect at about 2 bits per sec. but continued to improve up to at least 8 bits per sec., at about half the ideal slope. The findings are discussed in relation to the information-capacities measured in other tasks, and it is suggested that with full preview the rate should reach a maximum of about 10 bits per sec. Without preview the rate appears to be lowered by the need to offset response lag by predicting course behaviour.
straightjacketis required for the synaptic stabilization ofcacophony, a voltage-gated calcium channel α1 subunit
Authors: Ly Cindy V. , Yao Chi-Kuang , Verstreken Patrik , Ohyama Tomoko , Bellen Hugo J.
Published: April 2008

In a screen to identify genes involved in synaptic function, we isolated mutations in Drosophila melanogaster straightjacket (stj), an α2δ subunit of the voltage-gated calcium channel. stj mutant photoreceptors develop normal synaptic connections but display reduced “on–off” transients in electroretinogram recordings, indicating a failure to evoke postsynaptic responses and, thus, a defect in neurotransmission. stj is expressed in neurons but excluded from glia. Mutants exhibit endogenous seizure-like activity, indicating altered neuronal excitability. However, at the synaptic level, stj larval neuromuscular junctions exhibit approximately fourfold reduction in synaptic release compared with controls stemming from a reduced release probability at these synapses. These defects likely stem from destabilization of Cacophony (Cac), the primary presynaptic α1 subunit in D. melanogaster. Interestingly, neuronal overexpression of cac partially rescues the viability and physiological defects in stj mutants, indicating a role for the α2δ Ca2+ channel subunit in mediating the proper localization of an α1 subunit at synapses.
Functional expression of an insect cathepsin B‐like counter‐defence protein
Authors: Koo Y. D. , Ahn J.‐E. , Salzman R. A. , Moon J. , Chi Y. H. , Yun D.‐J. , Lee S. Y. , Koiwa H. , Zhu‐Salzman K.
Published: April 2008

Insects are capable of readjusting their digestive regimes in response to dietary challenge. Cowpea bruchids (Callosobruchus maculatus) strongly induce C. maculatus cathepsin B‐like cysteine protease 1 (CmCatB1) transcripts when fed diet containing a soybean cysteine protease inhibitor soyacystatin N (scN). CmCatB1 shares significant sequence similarity with cathepsin B‐like cysteine proteases. In this study, we isolated another cDNA, namely CmCatB2 that encodes a protein sequence otherwise identical to CmCatB1, but lacking a 70‐amino‐acid internal section. CmCatB1 and CmCatB2 probably resulted from alternate splicing events. Only the CmCatB1 transcript, however, exhibited differential expression in response to dietary scN. Further, this expression was only detectable in larvae, which is the developmental stage associated with food ingestion. The scN‐activated and developmentally regulated CmCatB1 expression pattern suggests it may have a unique function in insect counter‐defence against antinutritional factors. Heterologously expressed recombinant CmCatB1 protein exhibited enzymatic activity in a pH‐dependent manner. Activity of the protein was inhibited by both the cysteine protease inhibitor E‐64 and the cathepsin B‐specific inhibitor CA‐074, verifying its cathepsin B‐like cysteine protease nature. Interestingly, the enzymatic activity was unaffected by the presence of scN. Together, we have provided functional evidence suggesting that CmCatB1 confers inhibitor‐insensitive enzymatic activity to cowpea bruchids, which is crucial for insect survival when challenged by dietary protease inhibitors.
ORIGINAL ARTICLE: Mammals of Borneo – small size on a large island
Authors: Meiri Shai , Meijaard Erik , Wich Serge A. , Groves Colin P. , Helgen Kristofer M.
Published: April 2008

Aim  Island mammals have featured prominently in models of the evolution of body size. Most of these models examine size evolution across a wide range of islands in order to test which island characteristics influence evolutionary pathways. Here, we examine the mammalian fauna of a single island, Borneo, where previous work has detected that some mammal species have evolved a relatively small size. We test whether Borneo is characterized by smaller mammals than adjacent areas, and examine possible causes for the different trajectories of size evolution between different Bornean species.

Location  Sundaland: Borneo, Sumatra, Java and the Malay/Thai Peninsula.

Methods  We compared the mammalian body size frequency distributions in the four areas to examine whether the large mammal fauna of Borneo is more depauperate than elsewhere. We measured specimens belonging to 54 mammal species that are shared between Borneo and any of the other areas in order to determine whether there is an intraspecific tendency for Bornean mammals to evolve small body size. Using data on diet, body size and geographical ranges we examine factors that are thought to influence body size.

Results  Borneo has fewer large mammals than the other areas, but this is not statistically significant. Large Bornean mammals are significantly smaller than their conspecifics in the other regions, while there are no differences between the body sizes of mammals on Sumatra, Java and the Malay/Thai Peninsula. The finding that large mammals show the greatest size difference between Borneo and elsewhere contrasts with some models of size evolution on islands of different areas. Diet does not correlate with the degree of size reduction. Sunda region endemics show a weaker tendency to be small on Borneo than do widespread species.

Main conclusions  We suggest that soil quality may drive size evolution by affecting primary productivity. On Borneo, where soils are generally poor in nutrients, this may both limit biomass and cause mammals to be reduced in body size. We hypothesize that widespread species respond to low resource abundance by reducing in size, while endemic elements of the fauna have had longer to adjust to local conditions by altering their behaviour, physiology and/or ecology, and are thus similar in size across the region.
The spectrum of barriers to and facilitators of research utilization in Iranian nursing
Authors: Mehrdad Neda , Salsali Mahvash , Kazemnejad Anooshiravan
Published: April 2008

Aim.  The focus of the study is the identification of barriers to and facilitators of research utilization in nursing practice from the perspective of Iranian nurses.

Background.  In Iran, research utilization is a new phenomenon thus our knowledge with regard to those factors that promote or discourage research use is limited. No overall picture of the state of research utilization in Iran therefore exists.

Method.  A descriptive design is used. The questionnaire was distributed to 410 nurses from educational hospitals and nursing schools affiliated with Tehran Medical Sciences University in Iran.

Results.  The major barriers to research utilization were that the nurses do not have time to read research; facilities are inadequate for implementation; and nurses do not feel they have enough authority to change patient care procedures. Findings revealed a number of facilitators which were categorised into two main groups of human resources and individual/organisational factors.

Conclusion.  The healthcare system in Iran does not provide the incentive for nurses to engage in research or to avail themselves of research findings. Also, time is the major issue owing to a nursing shortage. If research utilization is to increase in Iran, therefore, the most important organisational change that needs to occur is the provision of available facilities for nurses to use research evidence.

Relevance to clinical practice.  Key factors that need attention in implementing research results into practice are suggested. Clearly, identification of barriers and facilitators is useful potentially to overcome barriers and enforce facilitators and this could ultimately improve nursing practice.
An empirical study of pupils' attitudes to computers and robots*
Authors: Moore J.L.
Published: April 2008

A 64‐item Likert type instrument assessed seven scales of pupils' attitude toward computers and robots. Scale scores were investigated as functions of pupils' sex, Piagetian stage, chosen course of study, home use of a microcomputer and experience of computer‐assisted learning (CAL). More favourable attitudes were held by boys and by pupils choosing Computer Studies. Amongst pupils not choosing Computer Studies, those reporting experience of CAL or high use of a home microcomputer showed smaller declines of attitudes over a 1‐year period.
Learning LOGO: effects on learning BASIC and statistics
Authors: Smith C. D.
Published: April 2008

Abstract Two experiments were conducted to examine the effects of a period of training in the use of the turtle graphics aspects of LOGO on both attitudes towards computers and the learning of BASIC and statistics. A group of 15 subjects spent 10 hours learning LOGO. Their performance on subsequent learning of BASIC was significantly better than that of a control group, but no differences were found in attitudes towards computers or in the learning of statistics.
Aspects of menu design
Authors: Clark D.
Published: April 2008

Abstract Menus are choice structures. This article explores the pros and cons of various menu layouts. Its findings are applicable to the whole range of computer‐assisted learning media from the micro through to touch screen interactive video.
On the road to Jerusalem: A computer‐assisted simulation game for religious education
Authors: Martin A. , Smyth I.
Published: April 2008

Abstract  This paper discusses a computer‐assisted simulation and database package designed for upper primary and secondary schools, and is also useful in teacher‐training. It allows groups of students to adopt the roles of characters travelling through Palestine at the time of the New Testament. The nature of the package and its use in the classroom are described, and the effect of this type of package on the roles of student and teacher considered.
Ways of learning in a computer‐based environment: some findings of the LOGO Maths Project
Authors: Hoyles C. , Sutherland R.
Published: April 2008

Abstract  This paper is derived from the LOGO Maths Project's investigation of the potential of LOGO in the secondary school mathematics classroom (1983–1986). The main focus of the work has been to discover whether and under what conditions the computer language LOGO can be used as an aid to pupils' learning and thinking in mathematics. Longitudinal case studies were undertaken for four pairs of pupils throughout the three years of the project. In addition the research was extended for two years into another eight schools. This paper presents the findings concerned with peer collaboration and the role of the teacher in the LOGO environment. It describes how LOGO work can be used to gain insights into pupils' conceptions of mathematical ideas. It also makes reference to gender issues in the wider context of computer use in the United Kingdom.
A short‐term plan for CAL
Authors: Nicolson R.I.
Published: April 2008

Abstract  The successful integration of computers into British schools provides one of the major educational challenges of the century. The plan for CAL outlined here is a ‘survival scheme’, concentrating on the progress needed if we are to remedy the current problems within the next 5 years. The objective is the introduction of ‘fourth generation’ hardware into an educational environment which has been fully prepared‐with a redesigned curriculum, high quantity and quality of curriculum‐related courseware, a well‐trained and enthusiastic teaching profession and a clear theoretical understanding of the issues underlying effective use of CAL. The short‐term strategy advocated involves; ‘host‐target’ software development; development of a CAL authoring system; provision of quality software via support for a limited number of ‘CAL demonstrator projects’; introduction of CAL systems for teacher training; and pure research aimed at better theoretical understanding of issues underlying CAL and the curriculum. Suggestions are made for implementation of many of the deails of the strategy.
Encouraging probabilistic thinking
Authors: Green D. R.
Published: April 2008

Abstract  This paper reports on research which indicates the weak understanding of tree diagrams of pupils aged 11–16 years and describes a computer program which seeks to overcome this, allowing the pupil to construct and analyse a simulated channel system down which balls may be rolled.
CAL delivery selection criteria and authoring systems
Authors: Black T. R.
Published: April 2008

Abstract  In the past, authoring systems have been used to generate computer‐assisted learning materials that have often followed the rather restrictive programmed learning format. A number of innovative ways of using recently developed systems to develop CAL packages that include a wider range of learning activities (access to data bases, simulations, interactive video, etc.) are described. Analogous to the concept of a media selection model, a computer delivery mode selection model is presented as an aid to decision making for designers. This increase in flexibility should broaden the applicability of computerassisted learning (CAL) to a wider range of educational objectives and raise the level of the cognitive emphasis in learning packages, as well as facilitate the implementation of visually appealing materials. The paper also implies a standard of acceptability for authoring systems.
The implications of the GCSE and CPVE on the use of computers in schools
Authors: Griffin J. A. , McGee P.
Published: April 2008

Abstract The introduction of the General Certificate of Secondary Education (GCSE) and the Certificate of Pre‐Vocational Education (CPVE) has influenced the quantity and type of computer use in secondary schools. This paper looks at the effects of these influences and examines ways in which schools and Local Education Authorities can accommodate them in the context of their more general development plans.
Introducing expert systems to pupils
Authors: Reynolds C. F.
Published: April 2008

Abstract  There are a number of practical advantages in exposing schoolchildren to simple expert systems. This should be done in order to give them a deeper understanding about what information is and how decisions are made by both people and advanced computer systems. However, there is a danger of blinding the pupils with science if expert system techniques are moved directly from the research laboratory to the classroom without appropriate adaptation.

This paper highlights the problems of producing a flexible and easily demonstrable system which can be used for teaching about expert systems and the underlying information processing principles. Key features of a working system, called Micro‐CODIL, are described. This uses a distinctive paradigm which is particularly suited to the needs of the classroom.

Examples discussed in the paper include a micro‐expert system relating to the finding of a body in a Danish bog, a brainteaser involving logical deduction to demonstrate production rules and a simple French‐English dictionary which can be used to widen pupils' ideas about ‘information’.
Development and classroom experimentation of interactive geometry exercises
Authors: Floris R. , Bevacqua G.
Published: April 2008

Abstract Practical experience in the development of computer‐based geometry exercises and their use in the classroom for a course on the equation of a straight line are presented. The task of creating the exercises with an authoring system for geometry is described first. Some didactical problems raised by this work are analysed in detail. The production time is estimated and discussed. A classroom experiment with pupils aged 15/16 is then presented and the teacher's organization problems are given (i.e. time spent on technical instruction, time‐sharing between theory and practice, tackling the lack of material). Some pedagogical issues are then discussed.
Education, Information technology and cognitive science
Authors: Scaife M.
Published: April 2008

Abstract This paper briefly sets out two main themes. The first is concerned with how information technology may be seen as both offering opportunities and posing problems from the perspectives of developmental psychology and education. The second delineates the main features of cognitive science and suggests ways in which it can help in formulating the solutions to some of these problems.
Athena, Andrew and Stanford: a look at implementation and evaluation in three large projects
Authors: Isaacs G.
Published: April 2008

Abstract Massachusetts Institute of Technology and Carnegie Mellon University have both embarked on enormous projects designed to implement workstation environments for use in academic endeavours. Project Athena at MIT is a network designed to service teaching and learning only, while the Andrew network at CMU is to service both teaching and research. Stanford University's computer‐intensive environment for teaching and learning owes no allegiance to either the Athena or the Andrew model. The environments at these three universities are summarized and placed in context.
Dyadic interactions at the microcomputer interface: a case study in computer assisted learning
Authors: Anderson A. , O'Hagan F. J.
Published: April 2008

Abstract A case study in which dyads of subjects (both a pupil‐pupil and a teacher‐pupil dyad) use a microcomputer computer assisted learning (CAL) program is discussed. We argue that an approach involving the videotaping of pupils' interactions around the computer, microanalysing the resulting dialogue, and relating the results from the dialogue analysis to learning outcomes is a potentially very powerful method for evaluating the educational efficacy of CAL software. The present case study describes a technique for collecting appropriate data, indicates the richness of such dialogue data and illustrates some of the hidden problems in CAL program use which other evaluation methods are unlikely to expose.
The potential of Information Technology within the English Curriculum
Authors: Adams Anthony
Published: April 2008

Abstract  This paper explores some of the implications of the recently issued Statutory Orders for English in the National Curriculum of England and Wales so far as Information Technology is concerned. After consideration of the extent to which there is now a legal requirement to use the new technologies in English classrooms, the paper considers how the use of such technology might be extended to develop and enhance good practice in the teaching and learning of English.
Why is science hard to learn?
Authors: Millar R.
Published: April 2008

Abstract This paper argues that science's reputation as a ‘hard’ subject can be attributed to four intrinsic features of science and/or learners: that science knowledge provides, for many learners, insufficient ‘pay off’ for the effort involved in understanding; that learning science involves reconstructions of meaning; that the tension between science as consensually agreed knowledge and science as enquiry is confusing and eventually alienating for many learners; and because science is abstract. The reasons for a link between abstraction and difficulty are briefly explored. It is suggested that certain extrinsic features of science education, resulting from choices by science educators, exacerbate these intrinsic difficulties.
Interactive videodiscs for science education
Authors: Ross S. M.
Published: April 2008

Abstract Videodisc technology allows the marriage of a uniquely versatile visual medium with interactive computer‐assisted learning packages and the combination can provide a very powerful educational resource. This review paper explores the teaching and learning potential of interactive video (IV), with reference to science courses, and describes some of the programmes currently in use.
Information Technology and group work in physics
Authors: Howe C. , Tolmie A. , Anderson A.
Published: April 2008

Abstract It is now widely accepted that the cost of computers means that work around them will usually be in group's work. Hence, the question is raised of whether the group context should be explicitly recognized in the software design. The present paper outlines a study which was intended to contribute to an answer. The study addressed the consequences of exchanging ideas while making joint decisions about the paths followed by falling objects. Based on results from 12–15‐year‐old pupils who responded to computer‐presented problems, the study indicates that benefits are to be gained, but that constraints additional to joint decision making may be necessary for optimal outcomes.
Hypertext in cognate‐language learning
Authors: Galletly J. , Butcher W. , Daryanani S.
Published: April 2008

Abstract  This paper reports on the results of and experiences gained from a project to investigate and evaluate the use of hypertext as a tool for developing CALL systems. The type of CALL system implemented was to some extent influenced by the desire to experiment with hypertext. Its novel features seemed to indicate that it would be ideal for the development of a cognate‐language learning package i.e. software which would aid the development of reading ability in a foreign language based on the knowledge of a related language. Accordingly, a package was developed which provides the ‘same’ prose passages in French and Spanish (with English normally operating as the first language). A reader is able to browse in one of these languages, trying to understand the meaning by either interpolating between cognate words or by moving between the identical passages of two (or even three) of the languages.
A model for teaching and research into computational modelling
Authors: dos Santos A. C. Kurtz , Ogborn J.
Published: April 2008

Abstract  We propose an instructional model for computational modelling, based on a methodology commonly described in the mathematical modelling literature. Computational modelling should be seen both at the level of creation of a given model, and at that of learning through the construction of series of models. We present an analysis of the learning needed for the construction of a model, and a further level of analysis for what is needed to generalize from particular models. We describe a way of representing qualitative knowledge of relationships, through the construction of causal diagrams. Finally we present a framework for evaluation of teaching, related to the analysis.
IT‐based open learning: tasks & tools
Authors: Goodyear P. , Steeples C.
Published: April 2008

Abstract This paper arises from early work in the ‘Just‐in‐Time Open Learning’ (JITOL) project supported by the European Commission in its DELTA Programme. It attempts to do the following things: provide a description of IT‐based open learning, identify a number of the key tasks carried out by the main participants in an IT‐based open learning environment, and review tools that can be used to support these tasks. The paper draws on several years experience of IT‐based distance teaching and on some user requirements studies. Some ideas are presented about user trials to be conducted in the second main phase of the JITOL project.
Computer literacy skills among school students and employees in industry
Authors: Harrison C. , Hay D. , Pierson A. , Burton J. K.
Published: April 2008

Abstract  A program was developed to examine the computer skills of 180 school leavers and 190 workers in industry. The 25‐minute task tested skills of using a mouse, typing information, and ordering parts for a LEGO construction. In general, school students performed better than the workers in industry, and males better than females. These results are attributed to the greater familiarity of males with computers, particularly in school, where differences in scores were particularly significant.
DIAG: a program to diagnose students' conceptual models in science
Authors: Boohan R.
Published: April 2008

Abstract  In recent years, much research has been undertaken to investigate the difference between pupils' beliefs and accepted ideas about various scientific concepts, such as force, light, energy and electricity, and the implications of these findings for classroom practice have been considered. In solving scientific problems, many students share common misconceptions or ‘models’ of the behaviour of a system or the nature of a phenomenon. This article describes a computer program which uses questionnaires to try to diagnose these conceptual models and to provide feedback to students. The program is not domain‐specific and questionnaires could be constructed for many topics, though work on the program so far has concentrated on diagnosing students' models of simple electrical circuits.
DICTOFUN: a concept dictionary for children
Authors: White A. , Easterbrook S.
Published: April 2008

Abstract Young children frequently experience problems when using conventional dictionaries if they cannot spell or even name the word they are looking for. Hence organising words by the way they are spelt is largely unproductive. This paper describes a referencing method for an on‐line concept dictionary where words are accessed via their meaning rather than by alphabetical entry. Concepts and sub‐concepts are linked together in a hierarchy to ensure that the search process is both intuitive and efficient, and takes full advantage of the associative organisation of human memory. The method has been used in a system, DICTOFUN, developed for children aged 8 ‐ 14. Preliminary interactions with children have been promising. Concept mapping proved intuitive and fun to use for children across this age range. The younger children were able to browse the system and discover new words, while the older children used it to create their own hierarchies.
Evaluation in DELTA
Authors: Cullen J. , Kelleher J. , Stern E.
Published: April 2008

Abstract This article outlines the thinking behind the evaluation strategy developed by ARTICULATE, an evaluation consortium within the European Community's DELTA programme on flexible and distance learning. The strategy is intended to guide ARTICULATE's own evaluation activities within DELTA and to give coherence to dispersed evaluation activities within this large scale decentralised R∓D programme. Evaluation frameworks and understandings of learning technology innovation are described as part of a ‘contingency’ approach to evaluation.
Electronic Study Books and learning style
Authors: De Diana I.P.F. , van der Heiden G.
Published: April 2008

Abstract  Attention has been drawn to the concepts of Electronic Books and Electronic Study Books. Several publications have discussed some main ideas (paradigms) for both concepts. For the Electronic Study Book as a learning environment, it is essential to consider individual modes of learning, usually termed ‘learning styles’. It is argued that Electronic Study Books should be adaptable in accordance with personal learning styles. Some options will be presented to link ‘styles’ and ‘books’. One such option is a Style Initiating Module which we are currently investigating.
Groupwork with Computers: an overview of findings
Authors: Hoyles C. , Healy L. , Pozzi S.
Published: April 2008

Abstract  The paper presents the main findings of the London‐based study, carried out as part of the ESRC project Groupwork with Computers. During this study, we attempted to identify the background and process factors which influence the success of groupwork with computers. The research used a multi‐site case study design in six schools and involved eight groups of six mixed‐sex, mixed‐ability pupils (aged 9–12) undertaking three mathematics tasks, two using LOGO and one a database. Our main findings suggest that group settings are only successful in terms of both group outcome and learning, if the group structures their activity in particular and identifiable ways. These organisational styles and patterns of interaction themselves are conditional on interpersonal and social characteristics of the group and class.
Professional development in transition: a Canadian provincial case study
Authors: Owston R. D.
Published: April 2008

Abstract There is no national information technology (IT) training policy in Canada as education is a provincial responsibility. IT training models vary considerably from province to province, but the Ontario Additional Qualification model for in‐service teacher training is perhaps one of the most extraordinary models found anywhere. This paper describes the Ontario model with particular reference to the component of it that deals with IT. The paper concludes with a discussion of the success of the model and future directions that in‐service training is likely to take in Ontario.
IT in teacher education in Denmark
Authors: Hjarnaa P. , Bollerslev P.
Published: April 2008

Abstract As with many European countries Denmark is experiencing change in teacher education and most notably in the wake of an act of government in 1992 which was designed to set out common aims for teacher education. Prior to that the content and structure of teacher education had been highly specified including, for example, the requirement that student teachers should take a course of 42 hours IT‐related lessons. This paper provides a brief history of the background to the changes in teacher education and focuses on the implications that the more flexible aims for teacher education have for the future integration of IT in teacher education.
Student IT capability within a school‐based primary ITT course
Authors: Murray D. , Collison J.
Published: April 2008

Abstract This study reports on a comparative survey of primary student teachers' use of IT in schools. Groups on a similar course but with different amounts of school placement were compared. Their changing attitudes and perceived competencies were identified. The level of support available in schools was also investigated. Whilst the support available in schools was usually limited by lack of equipment and teacher expertise, students on the more school‐based course were found to gain more experience of IT in schools and were more likely to have used a range of IT applications. The level of use of IT in schools is found to have a significant impact on students' confidence and attitudes towards IT. However, wide variation in students' experience is identified and strategies for overcoming this continuing problem are suggested.
Promoting IT competences with student Primary teachers
Authors: Robertson J.
Published: April 2008

Abstract Initial teacher education centres have a crucial role in promoting the use of information technology (IT) in schools through the opportunity to influence new teachers. There is some concern about the extent to which they are currently fulfilling their role. This paper reviews recent, relevant research with a view to identifying key factors influencing the quality of course provision. Gaps in current research are suggested and recommendations are made for the future.
Adaptation of courses for trans‐European tele‐learning
Authors: Collis B. , Parisi D. , Ligorio M.B.
Published: April 2008

Abstract This paper addresses the problems of adapting instructional courses for trans‐European tele‐learning and for enlarging the range of students and learning modalities in distance learning. Building on previous work on the portability of educational software, the paper examines various dimensions of adaptation of existing courses: (a) content, (b) instructional materials, (c) language issues, (d) instructional delivery, (e) the instructional setting of the course, and (f) the situation of the course in a programme of study, and considers how those dimensions will particularly affect course adaptation. From this analysis, a set of six guidelines is presented for course adaptation. The Commission of the European Community recently supported a trans‐European project, TeleScopia, which aimed at investigating these dimensions as research issues.
Groupwork and computers: task type and children's performance
Authors: Jackson A. , Kutnick P.
Published: April 2008

Abstract In the majority of British primary schools, children use the computer in groups of two or three. This is partly due to the lack of resources, that is, most classrooms still only have one or two computers to share between around 30 children. Groupwork on computers is also justified for pedagogic reasons. Previous research comparing children working in groups or alone has revealed an advantage for children working in groups although the work undertaken has generally been problem solving tasks. This investigation examined the performance of pairs and individual 6‐year old children on a drill and practice program using a pre‐test, intervention, post‐test design. In comparison to the problem solving evidence, individuals were found to have a significant advantage over pairs during the computer‐based task.
Children's talk in cooperative groups
Authors: Wild M. , Braid P.
Published: April 2008

Abstract Whilst cooperative group learning using computers undoubtedly encourages students' verbal interactions, few studies have focused upon the nature of these interactions. Many researchers have suggested there is a need to know how students interact with each other particularly in relation to group structures, tasks and software types. This study was undertaken to investigate the verbal interactions of students (about 10‐years old) when working in cooperative groups structured on ability (either homogeneous and heterogeneous) using simulation and word processing software. It was found that the largest element of students' talk when working in cooperative groups of either structure was cognitively oriented; that students situated in homogeneous groups are likely to produce more socially oriented talk than those in heterogeneous groups; that students working with word processing rather than simulation software are likely to produce more socially oriented and off‐task talk; and those using simulation software are more likely to use talk indicative of higher‐order cognitive processing. In general, this study found that task, software and to a lesser extent, group structure, influenced the interactions of students working in cooperative groups with CAL.
Efficacy of prolonged interferon‐alpha treatment in chronic hepatitis B patients with HBeAb: comparison between 6 and 12 months of therapy
Authors: Lopez‐Alcorocho J. M. , Bartolome J. , Cotonat T. , Carreño V.
Published: April 2008

Summary. We compared the response and the relapse rates of HBeAb‐positive patients treated with interferon‐alpha for 6 or 12 months. Thirty‐eight HBeAb‐positive patients which chronic hepatitis B were randomly allocated into two groups: Group I (19 patients receiving 10 MU of recombinant interferon‐alpha 2b three times a week for 2 months, followed by 5 MU three times a week for 2 months and then 3 MU three times a week for 2 months); Group II (19 patients receiving 10 MU of recombinant interferon‐alpha 2b three times a week for 2 months, followed by 5 MU three times a week for 2 months and then 3 MU three times a week for 8 months). At the end of treatment, alanine aminotransferase normalization was higher but not more significant in Group I than in II (53%vs 26%), while hepatitis B virus DNA clearance was similar in both groups (21% in Group I vs 26% in Group II). However, at 12 months of followup, biochemical relapses occurred only in Group I (60%vs 0% in Groups I and II, respectively). Five complete responded cleared hepatitis B surface antigen at that time. In conclusion, prolonged treatment of HBeAb patients is efficient in reducing the biochemical relapse.
Liver transplantation for acute liver failure: outcome analysis
Authors: Shakil A. O. , Dvorchik I. , Fung J. J. , Rakela J.
Published: April 2008

Summary. Acute liver failure (ALF) remains a major cause of morbidity and mortality. Before the availability of liver transplantation only 20% of patients with ALF survived. The clinical dilemma relates to the prognostication of these patients, as early liver transplantation has been associated with better outcomes. The eligibility for liver transplantation must therefore be quickly established. The patient's age, aetiology of disease, interval between the onset of jaundice and encephalopathy, blood pH, prothrombin time, serum bilirubin and serum creatinine levels has been identified as useful prognostic markers. The degree of hepatocyte necrosis on liver biopsy and estimated hepatic volume by computed tomography may also be valuable predictors of survival; however, further studies are needed.
Hepatocellular carcinoma and other primary liver cancers in hepatitis C patients in Sweden – a low endemic country
Authors: Strauss Reinhild , Törner Anna , Duberg Ann‐Sofi , Hultcrantz Rolf , Ekdahl Karl
Published: April 2008

Summary.  The aim of this study was to assess the risk of hepatocellular carcinoma (HCC) and other primary liver cancers (PLC) in the nationwide cohort of hepatitis C virus (HCV) infected patients in Sweden. The basis was the total HCV‐cohort notified in 1990–2004, after excluding 3238 people also reported with hepatitis B, the study cohort consisted of 36 126 people contributing an observation time of 246 105 person‐years. The most common route of transmission was intravenous drug use (57%). The national Cancer Registry was used for follow‐up, and 354 developed PLC (mainly HCC), of whom 234 were eligible for statistical analysis. The PLC incidence in the HCV cohort was compared with the incidence in the general population, and a standardized incidence ratio (SIR) was calculated for six different strata according to estimated duration of infection. The highest relative risk, SIR: 46 (95% CI: 36–56) was found in the stratum 25–30 years with HCV infection and SIR: 40 (95% CI: 31–51) in the stratum 30–35 years with infection. In the entire community‐based HCV cohort in Sweden we found a highly increased risk of liver cancer compared to the general population. The highest relative risk was among people who had been infected for more than 25 years.
Mother's and father's birthweight as predictors of infant birthweight
Authors: Little Ruth E.
Published: April 2008

Summary. Mothers' and fathers' birthweights are each significantly related to their infants' birthweight, even after control for 31 potentially confounding variables. The relationship is stronger for mothers and daughters than for other parent‐offspring pairs. Parents' birthweights together account for 2% of the variance in sons', and 5% of the variance in daughters' birthweights.

There are interactions of maternal birthweight with maternal adult weight, pregnancy weight gain, and parity; the predicted effect of maternal birthweight on infant birthweight is enhanced when the mother weighs more, gains more weight during pregnancy, or is multiparous. Race and parents' drinking and smoking also modify the predicted effect of parents' birthweights.

The correlation between mother and offspring birthweights has been attributed to the mother's own uterine experience and its effect on her later reproductive performance. However, the significant relationship of father and infant birthweights reported in this paper suggests that the fetal genes also play some role in determining size at birth.