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3D printing of composites has a high degree of design freedom, which allows for the manufacture of complex shapes that cannot be achieved with conventional manufacturing processes. This paper aims to assess the design variables that might affect the mechanical properties of 3D-printed fibre-reinforced composites.

Markforged Mark-Two printers were used to manufacture samples using nylon 6 and carbon fibres. The effect of fibre volume fraction, fibre layer location and fibre orientation has been studied using three-point flexural testing.

The flexural strength and stiffness of the 3D-printed composites increased with increasing the fibre volume fraction. The flexural properties were altered by the position of the fibre layers. The highest strength and stiffness were observed with the reinforcement evenly distributed about the neutral axis of the sample. Moreover, unidirectional fibres provided the best flexural performance compared to the other orientations. 3D printed composites also showed various failure modes under bending loads.

Despite multiple studies available on 3D-printed composites, there does not seem to be a clear understanding and consensus on how the location of the fibre layers can affect the mechanical properties and printing versatility. Therefore, this study covered this design parameter and evaluated different locations in terms of mechanical properties and printing characteristics. This is to draw final conclusions on how 3D printing may be used to manufacture cost-effective, high-quality parts with excellent mechanical performance.

Composites 3D printing has the potential to replace the conventional manufacturing processes for engineering applications because it allows for the manufacturing of complex shapes with the possibility of reducing the manufacturing cost. This paper aims to analyse the performance of 3D printed fibre reinforced polymer composites to investigate the energy absorption capabilities and the residual properties before and after impact.

Various composites composed of carbon fibres and Kevlar fibres embedded into both Onyx and nylon matrix were printed using Markforged-Two 3D printers. Specimens with different fibre orientations and fibre volume fractions (Vf) were printed. A drop-weight impact test was performed at energies of 2, 5, 8 and 10 J. Flexural testing was performed to evaluate the flexural strength, flexural modulus and absorbed energy under bending (AEUB) before and after impact. Additionally, 3D printed carbon fibre composites were tested at two different temperatures to study their behaviour under room and sub-ambient temperatures. Failure modes were investigated using optical and high depth of field microscopes for all 3D printed composite samples.

Kevlar/nylon composites with a unidirectional lay-up and 50% Vf exhibited the most prominent results for AEUB at room temperature. The high-Vf carbon fibre composite showed the highest ultimate strength and modulus and performed best at both temperature regimes.

The work, findings and testing produced in this paper are entirely original with the objective to provide further understanding of 3D printed composites and its potential for use in many applications.

Post-traumatic zygomatic osteotomy, fracture reduction, and orbital floor reconstruction pose many challenges for achieving a predictable, accurate, safe, and aesthetically pleasing result. This paper aims to describe the successful application of computer-aided design (CAD) and additive manufacturing (AM) to every stage of the process – from planning to surgery.

A multi-disciplinary team was used – comprising surgeons, prosthetists, technicians, and designers. The patient’s computed tomography scan data were segmented for bone and exported to a CAD software package. Medical models were fabricated using AM; for diagnosis, patient communication, and device verification. The surgical approach was modelled in the virtual environment and a custom surgical cutting guide, custom bone-repositioning guide, custom zygomatic implant, and custom orbital floor implant were each designed, prototyped, iterated, and validated using polymer AM prior to final fabrication using metal AM.

Post-operative clinical outcomes were as planned. The patient’s facial symmetry was improved, and their inability to fully close their eyelid was corrected. The length of the operation was reduced relative to the surgical team’s previous experiences. Post-operative scan analysis indicated a maximum deviation from the planned location for the largest piece of mobilised bone of 3.65 mm. As a result, the orbital floor implant which was fixed to this bone demonstrated a maximum deviation of 4.44 mm from the plan.

This represents the first application of CAD and AM to every stage of the process for this procedure – from diagnosis, to planning, and to surgery.

This paper examines the corporate and institutional responses to the challenge of HIV/AIDS in South Africa. The circumstances of South Africa have demonstrated the need for new ways of governance if businesses and society are to be sustainable. A confluence of historical, political and social factors in the 21st century, has produced the circumstances for new corporate principles, practices and reporting. The paper investigates the impact of institutional initiatives on corporate practices. Based on semi-structured interviews, the influences of the Global Reporting Initiative (GRI), the King Report, the Johannesburg Securities Exchange (JSE), and trade unions on corporate practices are explicated. There is no single path to a solution. What is clear is that firms cannot be uni-dimensional in the pursuit of profits, but have to be more ‘inclusive’, and not only in South Africa, but everywhere.

One of the nine thought provoking essays assembled by Peter Vergo in the recently published The New Museology (Reaktan Books, ISBN 0 948 462 035 hardback, ISBN 0 948 462 043 paperback) is “The Quality of Visitors' Experiences in Art Museums” in which Philip Wright discusses the lack of awareness among museum personnel of what exactly their institutions are doing, and indeed should do, in a period when “films, television, video and pop access photography have inevitably altered, if not actually undermined the hierarchy of images that museums aim to display”. Few curators have had professional surveys of their audience undertaken, some have dismissed colleagues' changes as pandering to commercialisation, and invest in sophisticated technology and displays in such a way as to distract from the integrity of the objects in their care.

This paper aims to show how implementing new information technology has expanded the role of librarians as educators and how this role has matched the evolution of new technology.

The paper looks at librarians' approaches to their role as educators and explores ways of most effectively implementing changes. By reviewing the literature and taking the old discourse around library education and information literacy, the paper reflects on the changing role of librarians in an era of greater access to technology, including Web 2.0.

Collaboration with faculty was found to be an essential feature of the most successful stories. Teaching students and faculty to use new information technologies may have become one of the major roles of librarians.

This paper demonstrates that the continual evolution of the web is causing a move from e‐libraries to mobile libraries, and that the educational role of the librarians must encompass this trend, and to anticipate similar future developments.

This is the tenth article on business and law (BSL) databases in a continuing series of articles summarising and commenting on new database products. Two companion articles have appeared, one covering science, technology and medicine (STM) in Online & CDROM Review vol. 21, no. 4 and the other covering social science, humanities, news and general (SSH) in Online & CDROM Review vol. 21, no. 5. The articles are based on the newly appearing database products in the Gale Directory of Databases. The Gale Directory of Databases (GDD) was created in January 1993 by merging Computer‐Readable Databases: A Directory and Data Sourcebook (CRD) together with the Directory of Online Databases (DOD) and the Directory of Portable Databases (DPD).

Function libraries, and indeed the majority of organisations, especially those operating on a commercial basis or utilising public funds, consist of material and human structures. The leaders of the human structure utilise personnel and materials in the pursuit of certain goals. Brech itemises four main elements in this process of planning and regulating enterprise activities. They comprise:

In the report of the Interdepartmental Committee on Meat Inspection of 1950, it was recommended that suitable candidates from the butchery trade should be enabled to qualify as meat inspectors and now the Authorised Officers (Meat Inspection) Regulations, 1960, give effect to this recommendation. The training and examination of candidates for these new posts will be under the auspices of the Royal Society of Health and a syllabus has been drafted comparable to that of the Meat and Other Foods Inspector's examination, but in meat only. Holders of the certificate will qualify for appointments as “authorised officers” under the Food & Drugs Act, 1955, with powers of inspection and seizure, but, again, in meat only. Appointments will be made by local authorities and the new inspectors will be integrated with the existing local authority meat inspection service and work under appropriate direction, although the circular of the Ministry of Agriculture, Fisheries and Food accompanying the regulations carries the suggestion that local authorities might permit individuals appointed to discharge the full duties of a meat inspector without “continuous supervision.”