Sozial Studies: How Travel Abroad Empowers a Global Perspective

The personal experiences and values of individual teachers can tend to restrict the ability to promote a “global perspective” in the social studies, the subject area most suited to that concept. One antidote to this instructional myopia is the prospect of overseas travel, in the form of study tours, the type of which have been shown to have a great impact in this area (Wilson, 1982, 1983, 1993a, 1993b; Germain, 1998; Kirkwood, 2002). This article is a reflection on the findings of a two-week study tour of Germany in 2013, sponsored by the Transatlantic Outreach Program and the Goethe-Institut. During this tour, I was able to visit German schools, corporations, museums, , and to meet German educators. In this article, the value of such experiences to promote a global perspective, essential to global education, is examined—additionally, I analyze the impact that the German sozial approach might have on American educational decisions.

Applications of Mechanics and Modelling to Biomechanical Themes

This paper examines the application of mechanics to model the behaviour of the human body. Understanding of this behaviour is necessary in order to improve medical interventions for injury and disease that affect the daily function of an individual. Modelling techniques are presented that enable predictions of how the tissues of the body respond to changes in their mechanical environment. Finite element methods are often used to model both hard and soft tissues and it is important to understand the limitations of these techniques but also their power in predicting responses that may lead to improvements in health care. Examples are presented of modelling plates to fix broken bones, how the next generation of artificial limbs might be attached directly to the skeleton and how osteoporosis affects the strength of the spine

Ability of modal analysis to detect osseointegration of implants in transfemoral amputees : a physical model study

Owing to the successful use of non-invasive vibration analysis to monitor the progression of dental implant healing and stabilization, it is now being considered as a method to monitor femoral implants in transfemoral amputees. This study uses composite femur-implant physical models to investigate the ability of modal analysis to detect changes at the interface between the implant and bone simulating those that occur during osseointegration. Using electromagnetic shaker excitation, differences were detected in the resonant frequencies and mode shapes of the model when the implant fit in the bone was altered to simulate the two interface cases considered: firm and loose fixation. The study showed that it is beneficial to examine higher resonant frequencies and their mode shapes (rather than the fundamental frequency only) when assessing fixation. The influence of the model boundary conditions on the modal parameters was also demonstrated. Further work is required to more accurately model the mechanical changes occurring at the bone-implant interface in vivo, as well as further refinement of the model boundary conditions to appropriately represent the in vivo conditions. Nevertheless the ability to detect changes in the model dynamic properties demonstrates the potential of modal analysis in this application and warrants further investigation

The Green Book: Race, Geography, and Critical Understanding

Social studies teachers face a number of disciplinary challenges--for instance, insufficient geographic knowledge, fewer opportunities for critical analysis amid shrinking instructional time--and, in terms of confronting discrimination and disparity, an increasingly racially segregated society. Teachers can, however, make excellent use of historical resources and modern mapping tools to empower students in their analysis of the Jim Crow era and segregation in American daily life. This article describes the use of The Negro Motorist Green Book, a guide produced from 1937 to 1963 for African-American drivers which detailed American businesses which catered to black travelers. Using the data from these books, students can create critical maps detailing both the state off American segregation and the efforts, through the 20th century, to subvert it

Categorisation of activities of daily living of lower limb amputees during short-term use of a portable kinetic recording system: a preliminary study

The purpose of this preliminary study was to determine the relevance of the categorisation of the load regime data to assess the functional output and usage of the prosthesis of lower limb amputees. The objectives were (A) to introduce a categorisation of load regime, (B) to present some descriptors of each activity and (C) to report the results for a case. The load applied on the osseointegrated fixation of one transfemoral amputee was recorded using a portable kinetic system for five hours. The periods of directional locomotion, localised locomotion and stationary loading occurred 44%, 34% and 22% of recording time and each accounted for 51%, 38% and 12% of the duration of the periods of activity, respectively. The absolute maximum force during directional locomotion, localised locomotion and stationary loading was 19%, 15% and 8% of the BW on the antero-posterior axis, 20%, 19% and 12% on the medio-lateral axis as well as 121%, 106% and 99% on the long axis. A total of 2,783 gait cycles were recorded. Approximately 10% more gait cycles and 50% more of the total impulse than conventional analyses were identified. The proposed categorisation and apparatus have the potential to complement conventional instruments, particularly for difficult cases

Development of a biaxial compression device for biological samples: preliminary experimental results for a closed cell foam

Biological tissues are subjected to complex loading states in vivo and in order to define constitutive equations that effectively simulate their mechanical behaviour under these loads, it is necessary to obtain data on the tissue's response to multiaxial loading. Single axis and shear testing of biological tissues is often carried out, but biaxial testing is less common. We sought to design and commission a biaxial compression testing device, capable of obtaining repeatable data for biological samples. The apparatus comprised a sealed stainless steel pressure vessel specifically designed such that a state of hydrostatic compression could be created on the test specimen while simultaneously unloading the sample along one axis with an equilibrating tensile pressure. Thus a state of equibiaxial compression was created perpendicular to the long axis of a rectangular sample. For the purpose of calibration and commissioning of the vessel, rectangular samples of closed cell ethylene vinyl acetate (EVA) foam were tested. Each sample was subjected to repeated loading, and nine separate biaxial experiments were carried out to a maximum pressure of 204 kPa (30 psi), with a relaxation time of two hours between them. Calibration testing demonstrated the force applied to the samples had a maximum error of 0.026 N (0.423% of maximum applied force). Under repeated loading, the foam sample demonstrated lower stiffness during the first load cycle. Following this cycle, an increased stiffness, repeatable response was observed with successive loading. While the experimental protocol was developed for EVA foam, preliminary results on this material suggest that this device may be capable of providing test data for biological tissue samples. The load response of the foam was characteristic of closed cell foams, with consolidation during the early loading cycles, then a repeatable load-displacement response upon repeated loading. The repeatability of the test results demonstrated the ability of the test device to provide reproducible test data and the low experimental error in the force demonstrated the reliability of the test data

Electrical Enviroments to Stimulate Bone Cell Development

Oral Presentation - no full written paper: The aim of this project was to evaluate the effects of mechanical strain and indirect electrical stimulation upon the development of bone forming osteoblast cells and any possible synergistic effects of the two stimulants. This aim was achieved by using a novel device, designed and developed with the capability of creating a cell substrate surface strain along with an exogenous electrical stimulant individually or at the same time. Proliferation and differentiation was determined as a measure of cellular development. The indirect electrical stimulation was achieved through the use of pulsed electromagnetic field (PEMF) stimulation while the mechanical strain was produced from the dynamic stretching of a deformable cell substrate. The PEMF signal mimicked a clinically available bone growth stimulator signal. Results showed reduced proliferation and increased differentiation (alkaline phosphatase activity) with SaOS-2 osteoblast-like cell cultures, which were exposed to indirect electrical stimulation. MG-63 osteoblast-like cell cultures also showed reduced proliferation, however they did not show an increase in their differentiation with PEMF exposure. Mechanical stimulation alone did not have a significant effect over either proliferation or differentiation, while a dual mechanical and electrical stimulation resulted in cellular differentiation significantly increasing. It is possible a synergistic interaction between the two stimulants is occurring on a biological level

The development of a component to improve the loading safety of bone-anchored prostheses

Use of socket prostheses Currently, for individuals with limb loss, the conventional method of attaching a prosthetic limb relies on a socket that fits over the residual limb. However, there are a number of issues concerning the use of a socket (e.g., blisters, irritation, and discomfort) that result in dissatisfaction with socket prostheses, and these lead ultimately a significant decrease in quality of life. Bone-anchored prosthesis Alternatively, the concept of attaching artificial limbs directly to the skeletal system has been developed (bone anchored prostheses), as it alleviates many of the issues surrounding the conventional socket interface.Bone anchored prostheses rely on two critical components: the implant, and the percutaneous abutment or adapter, which forms the connection for the external prosthetic system (Figure 1). To date, an implant that screws into the long bone of the residual limb has been the most common intervention. However, more recently, press-fit implants have been introduced and their use is increasing. Several other devices are currently at various stages of development, particularly in Europe and the United States. Benefits of bone-anchored prostheses Several key studies have demonstrated that bone-anchored prostheses have major clinical benefits when compared to socket prostheses (e.g., quality of life, prosthetic use, body image, hip range of motion, sitting comfort, ease of donning and doffing, osseoperception (proprioception), walking ability) and acceptable safety, in terms of implant stability and infection. Additionally, this method of attachment allows amputees to participate in a wide range of daily activities for a substantially longer duration. Overall, the system has demonstrated a significant enhancement to quality of life. Challenges of direct skeletal attachment However, due to the direct skeletal attachment, serious injury and damage can occur through excessive loading events such as during a fall (e.g., component damage, peri-prosthetic fracture, hip dislocation, and femoral head fracture). These incidents are costly (e.g., replacement of components) and could require further surgical interventions. Currently, these risks are limiting the acceptance of bone-anchored technology and the substantial improvement to quality of life that this treatment offers. An in-depth investigation into these risks highlighted a clear need to re-design and improve the componentry in the system (Figure 2), to improve the overall safety during excessive loading events. Aim and purposes The ultimate aim of this doctoral research is to improve the loading safety of bone-anchored prostheses, to reduce the incidence of injury and damage through the design of load restricting components, enabling individuals fitted with the system to partake in everyday activities, with increased security and self-assurance. The safety component will be designed to release or ‘fail’ external to the limb, in a way that protects the internal bone-implant interface, thus removing the need for restorative surgery and potential damage to the bone. This requires detailed knowledge of the loads typically experienced by the limb and an understanding of potential overload situations that might occur. Hence, a comprehensive review of the loading literature surrounding bone anchored prostheses will be conducted as part of this project, with the potential for additional experimental studies of the loads during normal activities to fill in gaps in the literature. This information will be pivotal in determining the specifications for the properties of the safety component, and the bone-implant system. The project will follow the Stanford Biodesign process for the development of the safety component

The mechanical response of the ovine lumbar anulus fibrosus to uniaxial, biaxial and shear loads

Analytical and computational models of the intervertebral disc (IVD) are commonly employed to enhance understanding of the biomechanics of the human spine and spinal motion segments. The accuracy of these models in predicting physiological behaviour of the spine is intrinsically reliant on the accuracy of the material constitutive representations employed to represent the spinal tissues. There is a paucity of detailed mechanical data describing the material response of the reinforced­ground matrix in the anulus fibrosus of the IVD. In the present study, the ‘reinforced­ground matrix’ was defined as the matrix with the collagen fibres embedded but not actively bearing axial load, thus incorporating the contribution of the fibre-fibre and fibre-matrix interactions. To determine mechanical parameters for the anulus ground matrix, mechanical tests were carried out on specimens of ovine anulus, under unconfined uniaxial compression, simple shear and biaxial compression. Test specimens of ovine anulus fibrosus were obtained with an adjacent layer of vertebral bone/cartilage on the superior and inferior specimen surface. Specimen geometry was such that there were no continuous collagen fibres coupling the two endplates. Samples were subdivided according to disc region - anterior, lateral and posterior - to determine the regional inhomogeneity in the anulus mechanical response. Specimens were loaded at a strain rate sufficient to avoid fluid outflow from the tissue and typical stress-strain responses under the initial load application and under repeated loading were determined for each of the three loading types. The response of the anulus tissue to the initial and repeated load cycles was significantly different for all load types, except biaxial compression in the anterior anulus. Since the maximum applied strain exceeded the damage strain for the tissue, experimental results for repeated loading reflected the mechanical ability of the tissue to carry load, subsequent to the initiation of damage. To our knowledge, this is the first study to provide experimental data describing the response of the ‘reinforced­ground matrix’ to biaxial compression. Additionally, it is novel in defining a study objective to determine the regionally inhomogeneous response of the ‘reinforced­ground matrix’ under an extensive range of loading conditions suitable for mechanical characterisation of the tissue. The results presented facilitate the development of more detailed and comprehensive constitutive descriptions for the large strain nonlinear elastic or hyperelastic response of the anulus ground matrix