Electronic marking of statistics assessments for bioscience students

We describe the main features of a program written to perform electronic marking of quantitative or simple text questions. One of the main benefits is that it can check answers for being consistent with earlier errors, so can cope with a range of numerical questions. We summarise our experience of using it in a statistics course taught to 200 bioscience students.

Electronic voting systems in undergraduate teaching

One of the major differences undergraduates experience during the transition to university is the style of teaching. In schools and colleges most students study key stage 5 subjects in relatively small informal groups where teacher–pupil interaction is encouraged and two-way feedback occurs through question and answer type delivery. On starting in HE students are amazed by the sizes of the classes. For even a relatively small chemistry department with an intake of 60-70 students, biologists, pharmacists, and other first year undergraduates requiring chemistry can boost numbers in the lecture hall to around 200 or higher. In many universities class sizes of 400 are not unusual for first year groups where efficiency is crucial. Clearly the personalised classroom-style delivery is not practical and it is a brave student who shows his ignorance by venturing to ask a question in front of such an audience. In these environments learning can be a very passive process, the lecture acts as a vehicle for the conveyance of information and our students are expected to reinforce their understanding by ‘self-study’, a term, the meaning of which, many struggle to understand. The use of electronic voting systems (EVS) in such situations can vastly change the students’ learning experience from a passive to a highly interactive process. This principle has already been demonstrated in Physics, most notably in the work of Bates and colleagues at Edinburgh.1 These small hand-held devices, similar to those which have become familiar through programmes such as ‘Who Wants to be a Millionaire’ can be used to provide instant feedback to students and teachers alike. Advances in technology now allow them to be used in a range of more sophisticated settings and comprehensive guides on use have been developed for even the most techno-phobic staff.

Structural, magnetic, and electronic properties of VxCr2−xS3(0

A new family of vanadium-substituted chromium sulfides (VxCr2-xS3, 0 < x < 2) has been prepared and characterized by powder X-ray and neutron diffraction, SQUID magnetometry, electrical resistivity, and Seebeck coefficient measurements. Vanadium substitution leads to a single-phase region with a rhombohedral Cr2S3 structure over the composition range 0.0 < x e 0.75, while at higher vanadium contents (1.6 e x < 2.0) a second single-phase region, in which materials adopt a cation-deficient Cr3S4 structure, is observed. Materials with the Cr2S3 structure all exhibit semiconducting behavior. However, both transport and magnetic properties indicate an increasing degree of electron delocalization with increasing vanadium content in this compositional region. Materials that adopt a Cr3S4-type structure exhibit metallic behavior. Magnetic susceptibility data reveal that all materials undergo a magnetic ordering transition at temperatures in the range 90–118 K. Low-temperature magnetization data suggest that this involves a transition to a ferrimagnetic state.

Electronic commerce in agriculture and agribusiness: the case of Emilia-Romagna (Italy )

Despite the expectations of the benefits of this tool, the adoption of Electronic Commerce (EC) by small and medium firms of the agro-food sector in Italy is still not frequent, however, the understanding of opportunities it could create and how they can be exploited remains a relevant issue. This study, carried out in the Emilia -Romagna region during 2002, illustrates the results of a survey of 208 firms at all stages of the agro-food chain aimed at understanding the use of the Internet and the strategies adopted for EC implementation. The results show a low level of implementation of the instrument and a limited variety of adoption strategies. Agro-food firms actually invest very little in EC focusing their efforts on the Internet as promotion tool, while web-based direct selling is confined to market niches. The view that the Internet would reverse the disadvantages of small firms appears by now non realistic, even if interesting opportunities for further development are still present.

First-principles study of the inversion thermodynamics and electronic structure of FeM2X4 (thio)spinels (M = Cr, Mn, Co, Ni; X = O, S)

FeM2X4 spinels, where M is a transition metal and X is oxygen or sulfur, are candidate materials for spin filters, one of the key devices in spintronics. We present here a computational study of the inversion thermodynamics and the electronic structure of these (thio)spinels for M = Cr, Mn, Co, Ni, using calculations based on the density functional theory with on-site Hubbard corrections (DFT+U). The analysis of the configurational free energies shows that different behaviour is expected for the equilibrium cation distributions in these structures: FeCr2X4 and FeMn2S4 are fully normal, FeNi2X4 and FeCo2S4 are intermediate, and FeCo2O4 and FeMn2O4 are fully inverted. We have analyzed the role played by the size of the ions and by the crystal field stabilization effects in determining the equilibrium inversion degree. We also discuss how the electronic and magnetic structure of these spinels is modified by the degree of inversion, assuming that this could be varied from the equilibrium value. We have obtained electronic densities of states for the completely normal and completely inverse cation distribution of each compound. FeCr2X4, FeMn2X4, FeCo2O4 and FeNi2O4 are half-metals in the ferrimagnetic state when Fe is in tetrahedral positions. When M is filling the tetrahedral positions, the Cr-containing compounds and FeMn2O4 are half-metallic systems, while the Co and Ni spinels are insulators. The Co and Ni sulfide counterparts are metallic for any inversion degree together with the inverse FeMn2S4. Our calculations suggest that the spin filtering properties of the FeM2X4 (thio)spinels could be modified via the control of the cation distribution through variations in the synthesis conditions.

Engineering the electronic bandgaps and band edge positions in carbon-substituted 2D boron nitride: a first-principles investigation

Modification of graphene to open a robust gap in its electronic spectrum is essential for its use in field effect transistors and photochemistry applications. Inspired by recent experimental success in the preparation of homogeneous alloys of graphene and boron nitride (BN), we consider here engineering the electronic structure and bandgap of C2xB1−xN1−x alloys via both compositional and configurational modification. We start from the BN end-member, which already has a large bandgap, and then show that (a) the bandgap can in principle be reduced to about 2 eV with moderate substitution of C (x < 0.25); and (b) the electronic structure of C2xB1−xN1−x can be further tuned not only with composition x, but also with the configuration adopted by C substituents in the BN matrix. Our analysis, based on accurate screened hybrid functional calculations, provides a clear understanding of the correlation found between the bandgap and the level of aggregation of C atoms: the bandgap decreases most when the C atoms are maximally isolated, and increases with aggregation of C atoms due to the formation of bonding and anti-bonding bands associated with hybridization of occupied and empty defect states. We determine the location of valence and conduction band edges relative to vacuum and discuss the implications on the potential use of 2D C2xB1−xN1−x alloys in photocatalytic applications. Finally, we assess the thermodynamic limitations on the formation of these alloys using a cluster expansion model derived from first-principles.

A compact low-cost electronic hardware design for actuating soft robots

A low cost, compact embedded design approach for actuating soft robots is presented. The complete fabrication procedure and mode of operation was demonstrated, and the performance of the complete system was also demonstrated by building a microcontroller based hardware system which was used to actuate a soft robot for bending motion. The actuation system including the electronic circuit board and actuation components was embedded in a 3D-printed casing to ensure a compact approach for actuating soft robots. Results show the viability of the system in actuating and controlling siliconebased soft robots to achieve bending motions. Qualitative measurements of uniaxial tensile test, bending distance and pressure were obtained. This electronic design is easy to reproduce and integrate into any specified soft robotic device requiring pneumatic actuation.

Electronic structure of Pd multi-layers on Re(0001): the role of charge transfer

Understanding the origin of the properties of metal-supported metal thin films is important for the rational design of bimetallic catalysts and other applications, but it is generally difficult to separate effects related to strain from those arising from interface interactions. Here we use density functional (DFT) theory to examine the structure and electronic behavior of few-layer palladium films on the rhenium (0001) surface, where there is negligible interfacial strain and therefore other effects can be isolated. Our DFT calculations predict stacking sequences and interlayer separations in excellent agreement with quantitative low-energy electron diffraction experiments. By theoretically simulating the Pd core-level X-ray photoemission spectra (XPS) of the films, we are able to interpret and assign the basic features of both low-resolution and high-resolution XPS measurements. The core levels at the interface shift to more negative energies, rigidly following the shifts in the same direction of the valence d-band center. We demonstrate that the valence band shift at the interface is caused by charge transfer from Re to Pd, which occurs mainly to valence states of hybridized s-p character rather than to the Pd d-band. Since the d-band filling is roughly constant, there is a correlation between the d-band center shift and its bandwidth. The resulting effect of this charge transfer on the valence d-band is thus analogous to the application of a lateral compressive strain on the adlayers. Our analysis suggests that charge transfer should be considered when describing the origin of core and valence band shifts in other metal / metal adlayer systems.

Electronic structure of porphyrin-based metal-organic frameworks and their suitability for solar fuel production photocatalysis

Metal-organic frameworks (MOFs) can be exceptionally good catalytic materials thanks to the presence of active metal centres and a porous structure that is advantageous for molecular adsorption and confinement. We present here a first-principles investigation of the electronic structure of a family of MOFs based on porphyrins connected through phenyl-carboxyl ligands and AlOH species, in order to assess their suitability for the photocatalysis of fuel production reactions using sunlight. We consider structures with protonated porphyrins and those with the protons exchanged with late 3d metal cations (Fe2+, Co2+, Ni2+, Cu2+, Zn2+), a process that we find to be thermodynamically favorable from aqueous solution for all these metals. Our band structure calculations, based on an accurate screened hybrid functional, reveal that the bandgaps are in a favorable range (2.0 to 2.6 eV) for efficient adsorption of solar light. Furthermore, by approximating the vacuum level to the pore center potential, we provide the alignment of the MOFs’ band edges with the redox potentials for water splitting and carbon dioxide reduction, and show that the structures studied here have band edges positions suitable for these reactions at neutral pH.

Enhancing email text production for users with motor impairments

People with motor impairments who use a switch device to interface with computers have poor access to affordable software for email communication. The MultiMail email package was developed with government support to provide email access solutions for these users and for others with a range of disabilities. In this paper, the development of accessible on-screen keyboards and a word prediction program which facilitates email text production is discussed. Technology solutions were informed by people with disabilities through focus group and survey data. The resulting cross-disability design of MultiMail provides innovative and cost-free solutions to email text production.

Case study of electronic networking in an initial teacher education course

Electronic networking ('computer-mediated communication1), considered to be ‘unique domain for educational activity’ (Harasim, 1989:50) and ‘new educational paradigm’ (Mason & Kaye, 1989:23), has been widely used and researched in K-12 schooling, place-based undergraduate subjects and distance education courses. However, only a limited number of reports of usage with experienced teachers (professional development), beginning teachers (induction support) and trainee teachers (initial training) have been published. Hence, little is known about the ways in which this new medium might contribute to the acquisition and maintenance of professional knowledge in the field of teacher education. The purpose of this study was to document an application of electronic networking in an initial 'school-based1 teacher education course. Three factors which were considered to be important in the adoption of electronic networking were specifically addressed: (a) the potential of the medium to attract and maintain a representative and comprehensive audience', (b) the willingness of participants to use the medium for the notation of ideas about teaching; and, (c) the extent to which reflection on practice was evident in network messages. This study also identified and investigated other effects which emerged as participants attempted to negotiate personal relationships with new technology. A case study was selected to investigate audience, notation, reflection, and other effects, in a particular application. Data were collected using participant observation, software-generated statistics, printed documentation, university records, questionnaires, interviews and content analysis of messages. These data were used to describe and analyse network participation by trainee teachers, classroom teachers and university staff. The data revealed that an audience did exist on the electronic network but that this was not comprehensive. Teachers had difficulty accessing the network because of other school commitments, access to equipment and personal competence with microcomputers. These difficulties indicated that developing and maintaining the teacher audience may be a major problem with electronic networking in initial teacher education. This case study revealed that deeply held concerns about notation of ideas by trainee teachers and classroom teachers can be powerful reasons for limited network participation. For trainee teachers, recording ideas publicly presented special difficulties associated with written communication. They were concerned about writing for an audience; about what to write about and how to write it. The loss of visual and verbal cues which form part of face-to-face communication was also a problem leading to concerns about how messages would be received by others. However, the overwhelming concern of almost all trainee teachers about presenting their own ideas was Tear of criticism' from peers (in particular), and other participants on the network. Trainee teachers expressed concerns about the 'dangers' of putting their thoughts in writing, the scrutiny their messages might have received from others, and the public 'criticism' about what they wrote which might have appeared on the network. Knowing that messages were stored on the network, and could be retrieved at some later date, heightened anxiety about the vulnerability of written communication; what was written on one occasion may have to be defended at some later date when the views expressed initially were no longer held. Classroom teachers were also unsure about recording their own ideas in an electronic form. Like trainee teachers, they were concerned about the scrutiny their contributions might receive from other users, and the lack of visual and verbal cues which they had learnt to use in face-to-face communication. Notating ideas in text-based messages which were archived (by the software), and retrievable by others later, was also daunting to many teachers. Another major 'danger' for teachers was the possible repercussions of 'public comment' about curriculum policy and initiatives which they thought might get them into 'trouble' with their employer. Since very few messages were contributed to conferences, there was little evidence of reflection in network communication. In the main, the network was not used to share information and ideas about curriculum and teaching. Public examples of collaboration between participants were not evident, and the 'special knowledge' held by members in each distinct group of users was not elaborated and discussed. Messages were not used to request information or clarification about issues, to outline the processes by which decisions about teaching were reached, or to synthesis ideas from different sources. The potential of the medium to operationalise reflective practice was not realised. Among the effects observed, the use of an anonymous account to access the network, and the impact this had on participation (in one conference) was considered to be a particularly significant finding. While the opportunity to systematically investigate the effects of anonymity on network participation and message contributions was not realised (by the author) while the research was in progress, the effects observed and discussed are considered to be important and worthy of further investigation. In this case study, the anonymous account helped trainee teachers mask concerns about personal writing skills and fear of criticism from others, indicating that anonymity may alter communication patterns, particularly in the early stages of network use. Given the data collected in this case study, and the interpretations placed on it by the author, a pessimistic assessment of the place of electronic networking in initial teacher education courses was presented. For this situation to change - that is, for electronic discussions to become more fully integrated into course activities - four issues which need to be addressed were identified and discussed. These included clarification of the role of collaboration amongst participants in initial teacher education, the ways in which collaboration can be facilitated using electronic networking, the problems of notation - such as the difficulty of expressing ideas about teaching in written form, and the concerns about permanently archived messages - for teachers and trainee teachers, and the lack of skills which many trainee teachers bring to electronic discussions. In the context of initial teacher education, it was suggested that these four aspects require clarification and development before the potential advantages of electronic networking can be realised. Some specific suggestions about how these issues might be resolved were presented.

Brave New World, 2050: The Implications of Shifting to Electronic Collections

This futuristic article discusses the shift in academic and research libraries to electronic collections in the context of information access, costs, publication models, and preservation of content. Certain factors currently complicate the shift to electronic formats and challenge their widespread acceptance. Future scenarios spanning skill ecosystems, technologies and workflows, and societal implications are explored as logical outgrowths of present circumstances.

April 2000: Internet Caveats, Electronic Classroom

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Ah, Libraries: How I Love the Smell of... Electronic Access?!

In the olden days, we Baby-Boomers would walk into our university or college libraries and pause just long enough to take in that wonderful smells of high grade cowhide leather and aging papyrus before rushing off to study. There was something about opening any leather bound edition of anything and being transported by the smell to some distant land, not unlike Charles Swann in Marcel Proust’s famous French novel, A La Recherché du Temps Perdu, Remembrance of Things Past.