Rapid prototyping and medical product development - getting there fast / first

Published ArticleWhen a patient is intubated during anesthesia it is very important that the Endo-tracheal (ET) tube remains in the correct place. If the tube deviates from the correct position it can cause one or both lungs to collapse and can be fatal. The idea behind the product was to design and manufacture a product that held an ET tube in place in a more secure manner than currently. It is common for an ET tube to move and or become dislodged due to various extraneous reasons. As with any new product, there was uncertainty about the design. Traditionally this meant the manufacturing of a hard tool and determining the right design by trail and error. Hard tooling allows for some small changes to be made, but if the changes are radical a new tool will have to be designed and manufactured. Prototyping revolutionized this process by simplifying the development iteration process, which means changes can be made quicker and easier, the costs will be lowered and the time-to-market is shortened

Rapid Prototyping and Medical Product Development-getting there fast/first

Published ArticleWhen a patient is intubated during anesthesia it is very important that the Endo-tracheal (ET) tube remains in the correct place. If the tube deviates from the correct position it can cause one or both lungs to collapse and can be fatal. The idea behind the product was to design and manufacture a product that held an ET tube in place in a more secure manner than currently. It is common for an ET tube to move and or become dislodged due to various extraneous reasons. As with any new product, there was uncertainty about the design. Traditionally this meant the manufacturing of a hard tool and determining the right design by trail and error. Hard tooling allows for some small changes to be made, but if the changes are radical a new tool will have to be designed and manufactured. Prototyping revolutionized this process by simplifying the development iteration process, which means changes can be made quicker and easier, the costs will be lowered and the time-to-market is shortened

Attitudes of pre-service mathematics teachers towards modelling : a South African inquiry

Abstract: This study explores the attitudes of mathematics pre-service teachers, based on their initial exposure to a model-eliciting challenge. The new Curriculum and Assessment Policy Statement determines that mathematics students should be able to identify, investigate and solve problems via modelling. The unpreparedness of mathematics teachers in teaching modelling is widely recognized. Modelling was thus included for the first time in the mathematics education curriculum of a South African university. Based on their modelling exposure, the participants revealed their attitudes via an Attitudes towards Mathematics Modelling Inventory. The Mann Whitney U-test detected significant differences between gender and achievement groups. Most participants displayed positive attitudes towards modelling, even after this brief exposure. The main implications of the study are that the modelling competencies of mathematics pre-service-teachers could be strengthened during their formal education by lecturers that adopt an appropriate modelling pedagogy that takes cognizance of their attitudes, while gradually building their confidence

Weight change and quality of life in a community-based population

*Objectives:* This study investigates the longitudinal association between 5-year weight change and quality of life (QoL) in Dutch men and women.

*Design:* A prospective cohort study (1998, 2000, 2003) in a population based sample. Subjects: 2,414 men and women from the Maastricht region of the Netherlands.

*Measurements:* QoL outcomes were measured by the RAND-36 (eight subscales and two overall composite scores, physical and mental health (PCS and MCS)). Weight was measured on a scale. Weight change was calculated as change in weight between 1998 and 2003. In addition, 5-year weight change was also categorized in three groups: weight losers, weight maintainers, and weight gainers. All analyses were stratified for gender.

*Results:* A total of 598 men (50%) and 646 women (54%) maintained their weight, 177 men (15%) and 163 women (14%) lost more than 2.5 kg, and 410 men (35%) and 379 women (32%) gained more than 2.5 kg. Associations between 5-year weight change and QoL were found for MCS ([beta] = 0.13, 95% CI: 0.02|0.24) in women, and PCS ([beta] = -0.09, 95% CI: -0.17|-0.00; [beta] = -0.10, 95% CI: -0.19|-0.01) in men and women respectively. Moreover, associations between weight change and QoL were most pronounced for women of normal weight and obese men. Furthermore, in both genders, weight gainers showed a greater reduction on all physical components of QoL compared with weight maintainers. However, after 5-years weight gainers and weight losers did not significantly differ from weight maintainers in the mean change of MCS and PCS.

*Conclusion:* Weight gain was inversely associated with the physical domains of QoL in women and obese men. Conversely, in women, weight gain was positively associated with the mental domains of QoL. No differences between weight losers and weight gainers were found in mean change of QoL compared with weight maintainers

The Evolutionary Role of Physician Assistants across the United States, Canada, and the United Kingdom

International Journal of Exercise Science 6(1) : 1-8, 2013. With physician shortages looming ominously on the horizon, healthcare systems across the globe are awaiting a surge of eager young doctors to enter the field. Much to the dismay of these systems, it does not appear that there will be a collective sigh of relief in the coming years. Fortunately there still remains a promising position to fill the gaps and potentially overcome the growing inundation of patients, shortage of general practice physicians, and ever growing underserved rural populations: the position of physician assistant (PA). Through this review, the evolution of the PA position will be discussed from the perspective of healthcare systems in the United States, Canada, and the United Kingdom. Further, an outline of the educational requirements, projected student debt-to-income ratios, and position availability will be touched upon

3D digital geometry designs for Poland’s syndrome using Magics and Geomagic® Freeform®

Published ArticlePurpose – Poland’s syndrome patients often seek medical interventions to improve their aesthetic appearances. Design and manufacturing technologies make it possible to produce custom-made implants for such medical conditions. The purpose of this study was to compare the 3D digital geometries that were designed using Magics and Geomagic® Freeform® for two anonymous case studies of Poland’s syndrome patients. Design/methodology/approach – Computed tomography data were acquired and processed in Mimics® to isolate the pectoralis muscles in STL file format. STL files were imported into Magics and Geomagic® Freeform® to design 3D digital geometries. Thereafter, comparative analyses were performed of the respective 3D digital geometries. Findings – The angle between the vertical and oblique planes for both sides of the thorax was 6.5° for the female and 14° for the male. The surface areas and volumes of the geometries for the female were smaller than the male. Deviation analyses between the healthy side and reconstructed side of a thorax showed that 73 per cent of the test points for Magics and 78 per cent for Geomagic® Freeform® fell in the nominated tolerance region of > 5 and <15 mm for the female. For the male, it was 83 per cent for Magics and 88 per cent for Geomagic® Freeform®. Practical implications – Geomagic® Freeform® provides a more versatile design environment; however, the STL editor Magics may be an option to design 3D geometries for less intricate and less contoured implants. Originality/value – This was a first attempt to compare the 3D geometries for Poland’s syndrome designed with an STL editor to those designed with a computer-aided design program

Rolpersepsies van dosente van eerstejaars in die natuurwetenskappe : ’n fokus op geslagsverskille

Role perceptions of lecturers of first year science students: A focus on gender differences. A marked increase in student enrolments in South African public universities over the last two decades, allowed substantially more ‘nontraditional’ students into the sector. These students typically have unsatisfactory levels of school performance, lack communication skills (especially in English) and mostly have first-generation status. The Faculty of Science at the University of Johannesburg (UJ) established its First Year Academy (FYA) in 2007. The FYA, a community of practice for lecturers of first-year students, promotes optimal student learning, and expects lecturers to optimise their facilitation of learning strategies. Not much is known (research-wise) about role adaptions that lecturers of first-year students (especially in science faculties) are expected (forced?) to make in such circumstances. A literature-validated Likert-type questionnaire, involving 53 first-year lecturers (almost 60% females), was subsequently administered. The survey gathered perceptions in respect of eight literature-based roles that lecturers (could or should) play when dealing with first-year students, as well as their self-appraised competence in fulfilling these roles. The Mann-Whitney U-test revealed significant differences between the perceived role importance and competence of male and female lecturers in respect of certain roles. The study revealed a significant relationship between the gender and opinions (and also behaviours) of science lecturers for first-year students at UJ. Capacity building geared at the more proficient execution of the roles of course designer, teacher, course manager and peer consultant is regarded as vital. A tailor-made professional development programme is offered by the Faculty of Science’s FYA as of 2014

Additive Manufacturing of Devices Used for Collection and Application of Cereal Rust Urediniospores

Published ArticleOptimized inoculation procedures are an important consideration in achieving repeatable plant infection when working with biotrophic rust fungi. Several plant pathology laboratories specializing in rust research employ a system where the collection and application of fungal spores are accomplished using an exchangeable gelatin capsule. Urediniospores are collected from erumpent pustules on plant surfaces into a capsule fitted to a cyclone collector controlled by a vacuum pump. By adding light mineral oil to the same capsule, the spore suspension is then sprayed onto plants by means of a dedicated atomizer (inoculator) connected to an air pressure source. Although devices are not commercially available, modern day technologies provide an opportunity to efficiently design and manufacture collectors and inoculators. Using a process called Additive Manufacturing (AM), also known as “3D printing,” the bodies of a collector and inoculator were digitally designed and then laser-sintered in nylon. Depending on availability, copper or aluminum tubes were fitted to the bodies of both devices afterward to either facilitate directed collection of spores from rust pustules on plant surfaces or act as a siphon tube to deliver the spore suspension contained in the capsule. No statistical differences were found between AM and metal inoculators for spray delivery time or spore deposition per unit area. In replicated collection and inoculation tests of wheat seedlings with urediniospore bulks or single pustule collections of Puccinia triticina and P. graminis f. sp. tritici, the causal organisms of leaf rust and stem rust, consistent and satisfactory infection levels were achieved. Immersing used devices in acetone for 60 s followed by a 2 h heat treatment at 75 C produced no contaminant infection in follow-up tests

Additive Manufacturing of Devices Used for Collection and Application of Cereal Rust Urediniospores

Optimized inoculation procedures are an important consideration in achieving repeatable plant infection when working with biotrophic rust fungi. Several plant pathology laboratories specializing in rust research employ a system where the collection and application of fungal spores are accomplished using an exchangeable gelatin capsule. Urediniospores are collected from erumpent pustules on plant surfaces into a capsule fitted to a cyclone collector controlled by a vacuum pump. By adding light mineral oil to the same capsule, the spore suspension is then sprayed onto plants by means of a dedicated atomizer (inoculator) connected to an air pressure source. Although devices are not commercially available, modern day technologies provide an opportunity to efficiently design and manufacture collectors and inoculators. Using a process called Additive Manufacturing (AM), also known as “3D printing,” the bodies of a collector and inoculator were digitally designed and then laser-sintered in nylon. Depending on availability, copper or aluminum tubes were fitted to the bodies of both devices afterward to either facilitate directed collection of spores from rust pustules on plant surfaces or act as a siphon tube to deliver the spore suspension contained in the capsule. No statistical differences were found between AM and metal inoculators for spray delivery time or spore deposition per unit area. In replicated collection and inoculation tests of wheat seedlings with urediniospore bulks or single pustule collections of Puccinia triticina and P. graminis f. sp. tritici, the causal organisms of leaf rust and stem rust, consistent and satisfactory infection levels were achieved. Immersing used devices in acetone for 60 s followed by a 2 h heat treatment at 75°C produced no contaminant infection in follow-up tests