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Radiotherapy relies on the delivery of radiation to cancer cells with millimetre accuracy, and immobilisation of patients is essential to minimise unwanted damage to surrounding healthy cells due to patient movement. Traditional thermoformed face masks can be uncomfortable and stressful for patients and may not be accurately fitted. The purpose of this study was to use 3D scanning and additive manufacturing to digitise this workflow and improve patient comfort and treatment outcomes.

The head of a volunteer was scanned using an Artec Leo optical scanner (Artec, Luxembourg) and ANSYS (Ansys, Canonsburg, USA) software was used to make two 3D models of the mask: one with a nose bridge and one open as would be used with optical surface guidance. Data based on measurements from ten pressure sensors around the face was used to perform topology optimisation, with the best designs 3D printed using fused deposition modelling (FDM) and tested on the volunteer with embedded pressure sensors.

The two facemasks proved to be significantly different in terms of restricting head movement inside the masks. The optimised mask with a nose bridge effectively restricted head movement in roll and yaw orientations and exhibited minimal deformation as compared to the open mask design and the thermoformed mask.

The proposed workflow allows customisation of masks for radiotherapy immobilisation using additive manufacturing and topology optimisation based on collected pressure sensor data. In the future, sensors could be embedded in masks to provide real-time feedback to clinicians during treatment.

The purpose of this study is, to compare laser-based additive manufacturing and subtractive methods. Laser-based manufacturing is a widely used, noncontact, advanced manufacturing technique, which can be applied to a very wide range of materials, with particular emphasis on metals. In this paper, the governing principles of both laser-based subtractive of metals (LB-SM) and laser-based powder bed fusion (LB-PBF) of metallic materials are discussed and evaluated in terms of performance and capabilities. Using the principles of both laser-based methods, some new potential hybrid additive manufacturing options are discussed.

Production characteristics, such as surface quality, dimensional accuracy, material range, mechanical properties and applications, are reviewed and discussed. The process parameters for both LB-PBF and LB-SM were identified, and different factors that caused defects in both processes are explored. Advantages, disadvantages and limitations are explained and analyzed to shed light on the process selection for both additive and subtractive processes.

The performance of subtractive and additive processes is highly related to the material properties, such as diffusivity, reflectivity, thermal conductivity as well as laser parameters. LB-PBF has more influential factors affecting the quality of produced parts and is a more complex process. Both LB-SM and LB-PBF are flexible manufacturing methods that can be applied to a wide range of materials; however, they both suffer from low energy efficiency and production rate. These may be useful when producing highly innovative parts detailed, hollow products, such as medical implants.

This paper reviews the literature for both LB-PBF and LB-SM; nevertheless, the main contributions of this paper are twofold. To the best of the authors’ knowledge, this paper is one of the first to discuss the effect of the production process (both additive and subtractive) on the quality of the produced components. Also, some options for the hybrid capability of both LB-PBF and LB-SM are suggested to produce complex components with the desired macro- and microscale features.

This paper reviews the synergy of Industry 4.0 and additive manufacturing (AM) and discusses the integration of data-driven manufacturing systems and product service systems as a key component of the Industry 4.0 revolution. This paper aims to highlight the potential effects of Industry 4.0 on AM via tools such as digitalisation, data transfer, tagging technology, information in Industry 4.0 and intelligent features.

In successive phases of industrialisation, there has been a rise in the use of, and dependence on, data in manufacturing. In this review of Industry 4.0 and AM, the five pillars of success that could see the Internet of Things (IoT), artificial intelligence, robotics and materials science enabling new levels of interactivity and interdependence between suppliers, producers and users are discussed. The unique effects of AM capabilities, in particular mass customisation and light-weighting, combined with the integration of data and IoT in Industry 4.0, are studied for their potential to support higher efficiencies, greater utility and more ecologically friendly production. This research also illustrates how the digitalisation of manufacturing for Industry 4.0, through the use of IoT and AM, enables new business models and production practices.

The discussion illustrates the potential of combining IoT and AM to provide an escape from the constraints and limitations of conventional mass production whilst achieving economic and ecological savings. It should also be noted that this extends to the agile design and fabrication of increasingly complex parts enabled by simulations of complex production processes and operating systems. This paper also discusses the relationship between Industry 4.0 and AM with respect to improving the quality and robustness of product outcomes, based on real-time data/feedback.

This research shows how a combined approach to research into IoT and AM can create a step change in practice that alters the production and supply paradigm, potentially reducing the ecological impact of industrial systems and product life cycle. This paper demonstrates how the integration of Industry 4.0 and AM could reshape the future of manufacturing and discusses the challenges involved.

This paper aims to present a comprehensive review of the laser engineered net shaping (LENS) process in an attempt to provide the reader with a deep understanding of the controllable and fixed build parameters of metallic parts. The authors discuss the effect and interplay between process parameters, including: laser power, scan speed and powder feed rate. Further, the authors show the interplay between process parameters is pivotal in achieving the desired microstructure, macrostructure, geometrical accuracy and mechanical properties.

In this manuscript, the authors review current research examining the process inputs and their influences on the final product when manufacturing with the LENS process. The authors also discuss how these parameters relate to important build aspects such as melt-pool dimensions, the volume of porosity and geometry accuracy.

The authors conclude that studies have greatly enriched the understanding of the LENS build process, however, much studies remains to be done. Importantly, the authors reveal that to date there are a number of detailed theoretical models that predict the end properties of deposition, however, much more study is necessary to allow for reasonable prediction of the build process for standard industrial parts, based on the synchronistic behavior of the input parameters.

This paper intends to raise questions about the possible research areas that could potentially promote the effectiveness of this LENS technology.

Additive manufacturing (AM) offers potential solutions when conventional manufacturing reaches its technological limits. These include a high degree of design freedom, lightweight design, functional integration and rapid prototyping. In this paper, the authors show how AM can be implemented not only for prototyping but also production using different optimization approaches in design including topology optimization, support optimization and selection of part orientation and part consolidation. This paper aims to present how AM can reduce the production cost of complex components such as jet engine air manifold by optimizing the design. This case study also identifies a detailed feasibility analysis of the cost model for an air manifold of an Airbus jet engine using various strategies, such as computer numerical control machining, printing with standard support structures and support optimization.

Parameters that affect the production price of the air manifold such as machining, printing (process), feedstock, labor and post-processing costs were calculated and compared to find the best manufacturing strategy.

Results showed that AM can solve a range of problems and improve production by customization, rapid prototyping and geometrical freedom. This case study showed that 49%–58% of the cost is related to pre- and post-processing when using laser-based powder bed fusion to produce the air manifold. However, the cost of pre- and post-processing when using machining is 32%–35% of the total production costs. The results of this research can assist successful enterprises, such as aerospace, automotive and medical, in successfully turning toward AM technology.

Important factors such as validity, feasibility and limitations, pre-processing and monitoring, are discussed to show how a process chain can be controlled and run efficiently. Reproducibility of the process chain is debated to ensure the quality of mass production lines. Post-processing and qualification of the AM parts are also discussed to show how to satisfy the demands on standards (for surface quality and dimensional accuracy), safety, quality and certification. The original contribution of this paper is identifying the main production costs of complex components using both conventional and AM.

The factories are instructed as to what kinds of pack they are to produce, and their product is controlled by samples sent at specified times to the research laboratory. With greater and less attention to detailed steps the whole of agriculture and the food industry in Italy is so controlled. In Germany can be noted as an example the development on a large scale of the fishing industry in the Baltic—the scrapping of the privately‐owned small fishing boats in that sea—the launching of large vessels with their factory vessels in attendance— the keenness with which every step in the development of fish preservation has been followed—the official tests on such methods as the American Birdseye Quick Freezing, the German Heckerman process, the English Z process, and the building and the equipping of the large factories where the whole of the waste fish products are worked up into edible and useful products. This last is the keynote of the German system : waste nothing. The recovery of waste fats has been practised in Germany in an intensive fashion for several years. There have been in Germany other changes of a more subtle character, and not so obvious to the outside world. The food laws of Germany were such that the nation could be justly proud of them, but for some time there has been a distinct slackening of the control—as for example in the use of preservatives. These were strictly limited in kind and number—but even before the present phase the blind eye of the official had often been turned towards the use of disallowed preservatives and I am given to understand that certain chemicals, erstwhile forbidden, can now be used officially. It may be policy for our Ministry of Health to aid in the present critical situation by relaxing some of the regulations at present in force. Those preservatives to be released would not in any way lower the nutritional value of the foods, nor would there be allowed any of those preservatives against which a case has been made in respect of their physiological action. The impetus given to research work by totalitarian states should be an inspiration to the democracies. One of the first things the Italian Government took in hand after their conquest of Abyssinia was a scientific survey of the natural products of the country. A recent issue of Nature states that the first number of a new official Italian journal contains the results of the first three years' work on the fish of the inland waters of the former Ethiopia. As Nature points out, the far greater areas of British Eastern Africa have been subjected simply to spasmodic and short‐termed scientific examinations, chiefly resulting from the initiative of private individuals or of institutions. It is to be stressed, however, that the stimulus given to scientific studies of food production and manufacture both in Germany and Italy was activated by abnormal conditions. In neither the one nor the other can it be said that the development was a natural one—in both it was originated by the desire of the government to make the country as self‐sufficient as possible in case of war, and therefore the whole idea was abnormal and biased. In this country and in the United States the development has followed much sounder lines. In this country the standard of living has become remarkably high, although perhaps somewhat lop‐sided. One might quote the example of bread. The loaf as we know it to‐day is made almost wholly from wheat flour, derived from that portion of the wheat kernel which gives the whitest flour. The Ministry of Health has, I think, been very properly concerned to maintain our high standard and has looked with disfavour on flours which, in order to simulate that particular white portion of the wheat grain, have been bleached. America is the only other country in the world where the people demand white loaves of such delicate and even texture. There much be something very attractive to the public in this type of loaf: some of us remember the fiasco of the standard bread, and members of the bakery trade know what a small proportion of their sales are concerned with brown loaves. The general character of the bread in continental European countries is very different; even the delightful loaves of France, generally well baked, are dark in comparison, although in no sense “ brown ” or “ whole‐meal.” In most countries flours other than wheat are incorporated. We may have to incorporate potato‐flour, but if this is done in any large quantity the resultant loaf has an entirely different texture. It is obvious that the dividing line between the scope of agriculture and that of the food industry is essentially ill‐defined. The importance, however, of the pre‐industrial treatment is such that it is really impossible to dissociate the scientific work of the agriculturalist from that of the industrialist. To quote examples :— Under the aegis of the Food Investigation Board a study has been made of the production of bacon in this country, with remarkably successful results to the farmer, to the bacon‐curer and to the consumer. Similarly the extensive series of experiments carried out by the Food Investigation Board on the storage of fruit has had great success, and the economic effect on the fruit trade, not only here, but also in the Dominions and Colonies cannot be estimated at the moment. An agricultural study of great importance to the housewife was undertaken by the Potato Marketing Board; this was concerned with the blackening of potatoes and was unfortunately not concluded when the war brought a sudden halt to the work. The problem of obtaining “ figures ” for characteristics of food is the most difficult with which the chemist has to deal. There is no method by which palatability can be registered, for it is compounded of many factors which themselves are not possible of measurement. Flavour, appearance and edibility are all concerned. It is comparatively simple to connect softness on the palate of a cream centre of a chocolate with the size of the grain of the sugar crystals, or the smoothness of an ice cream with the size of the ice‐crystals, but to express the texture of a cake in terms measuring the reaction of the palate, or the toughness or tenderness of a beef‐steak are far more difficult. This last example has been considered in some detail. Much work has been done at the Low Temperature Station at Cambridge on methods of judging the tenderness of meat. There is no simple method of reproducing the complicated movement of the jaws in mastication—but the consumer of the steak judges the tenderness by the reactions of his jaws to the muscle fibre, and the problem is complicated by the fact that the judgment of a person with a denture is entirely different from that of a person with his natural teeth; it has been estimated, for example, that the pressure which can be applied during mastication is only, even by those with the most perfect denture, one tenth that of normal. A somewhat complicated instrument has been designed and constructed at the Research Station at Karlsruhe in order to make possible investigations on the problem of the toughness of meat. Sufficient data have not yet been accumulated to pass judgment on its efficiency but it appears to be the most satisfactory attempt yet made to enable definite measurements of the toughness of meat to be determined. These are but examples of the general trend of scientific work in food production and manufacture, examples of the range of subjects and problems being attacked with an ever increasing vigour.

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This comparative and qualitative study-in-progress focuses on two early childhood teacher education (ECTE) programs in contexts where the participants are undergoing rapid social and personal change: a program in Namibia and a training program for immigrant childcare educators in Canada. The objective is to provide in-depth understanding of the ways in which differing ideas about ECTE are reflected in practice. It is important to ensure that ECTE programs prepare teachers to dovetail children’s preparation for school with meaningful connections to the culture and language of the home community, since more and more children spend their preschool years in early childhood (EC) centers that are becoming increasingly westernized in character. Without such connections, children in settings undergoing rapid change will continue to drop out of school before literacy and other skills are firmly established. The data will stem from analysis of early childhood care and education and ECTE curricula; policy and other documents; focused observations in ECTE classrooms and teaching practica; and interviews with teacher educators, education officers, teachers, parents, and community leaders. The results are expected to illuminate issues and strategies which are most likely to be effective for ECTE programs, with implications for teacher education in a range of settings in both the majority and minority worlds.