Global South perspectives on social justice

This paper draws on two studies that utilised an occupational science lens in understanding daily-life issues for Global South communities. International communities are experiencing fragmentation due to oppressive and unjust policies at home, or forced migration to safer and more just contexts. Studying the communal daily experiences of groups struggling against social injustice has become a key theme within occupational science, which is attempting to become a more inclusive and relevant field of study, by moving beyond the individual as a unit of study to focus on communal everyday experiences, including groups in the Global South. Boaventura de Sousa Santos described an ‘Epistemology of the South’ – a movement of thought and praxis from communities in the Global South who were struggling against socio-political phenomena related to colonialism, patriarchy, and globalised neoliberal capitalism. This movement is based on the need to learn from how communities resist such oppression in their daily lives to create social justice and ‘cognitive justice’ that would enable scholarly work to move beyond what Edward Said termed the ‘Epistemology of Imperialism’ – resulting from ignoring, or ‘othering’/’essentialising’, the experiences of marginalised groups in the process of knowledge production. Two processes are needed: ‘inter-cultural translation’ – the comparing and contrasting of ideas and practices of different communities; and the ‘ecologies of knowledge’, which involves stepping back from Eurocentric traditions to allow other analytical spaces that can explain reality to be involved in producing appropriate knowledge and theories that will contribute to social justice (Santos, 2014). The first study is a de-colonial ethnography in which the researcher’s “ability to shuttle between contrasting worlds of experience” was pivotal in researching olive growing as a daily form of resistance in Palestine (Zureik, 2014: 20). What emerged was a group of daily practices that were founded on historical, socio-political, cultural and spiritual principles. Olive growers in Palestine were observed to experience ‘occupational injustice’, or more specifically ‘occupational apartheid’, that is a particular form of social injustice based on restrictions on their daily lives imposed because of who they were (their belonging to Palestinian communities). Yet, rather than passively accept this situation, and despite all odds, they have continued this ancient, highly meaningful, and communal activity. This resilience was enabled by their need to survive and be dignified (Sutra/doing-being), to express solidarity and collaboration (‘Awna/belonging) and to aspire for a better shared future (Sumud/belonging-becoming) – and by their insistence upon meeting these collective needs. The second study addresses what is considered an increasingly prevalent social issue - the burden of older immigrants on host societies (Angel, 2003). This grounded theory study explored how Indian, Chinese and Korean older migrants to New Zealand sought to engage in everyday occupations, such as gardening, singing and caring for grandchildren, and thereby make valued contributions to their new community. Using an occupational science lens to critically examine the data revealed that these older immigrants were conscious of what New Zealand had to offer them and were determined not to take these opportunities for granted. Rather, through a social process of ‘strengthening community’, these elders worked to actively give back to their new homeland. However, coming to this understanding required further developing grounded theory methodology to encompass ‘inter-cultural translations’, as well as advance ‘ecologies of knowledge’. A willingness to employ new methods and ways of researching what may be framed as social problems from Global South perspectives is critical if we are to advance global understandings of the contributions that marginalised groups within society have to offer

Jacobian-Based Iterative Method for Magnetic Localization in Robotic Capsule Endoscopy

The purpose of this study is to validate a Jacobian-based iterative method for real-time localization of magnetically controlled endoscopic capsules. The proposed approach applies finite-element solutions to the magnetic field problem and least-squares interpolations to obtain closed-form and fast estimates of the magnetic field. By defining a closed-form expression for the Jacobian of the magnetic field relative to changes in the capsule pose, we are able to obtain an iterative localization at a faster computational time when compared with prior works, without suffering from the inaccuracies stemming from dipole assumptions. This new algorithm can be used in conjunction with an absolute localization technique that provides initialization values at a slower refresh rate. The proposed approach was assessed via simulation and experimental trials, adopting a wireless capsule equipped with a permanent magnet, six magnetic field sensors, and an inertial measurement unit. The overall refresh rate, including sensor data acquisition and wireless communication was 7 ms, thus enabling closed-loop control strategies for magnetic manipulation running faster than 100 Hz. The average localization error, expressed in cylindrical coordinates was below 7 mm in both the radial and axial components and 5° in the azimuthal component. The average error for the capsule orientation angles, obtained by fusing gyroscope and inclinometer measurements, was below 5°

A disposable continuum endoscope using piston-driven parallel bellow actuator

This paper presents a novel low cost disposable continuum endoscope based on a piston-driven parallel bellow actuator design. The parallel bellow actuator achieves motion by being pressurized via displacement-controlled pistons. The displacements are generated by rack-and-pinion mechanisms using inexpensive stepper motors. The design concept provides a potential alternative solution to upper gastrointestinal (UGI) diagnosis. The modularity and the use of inexpensive components allow for low fabrication costs and disposability. The use of robotic assistance could facilitate the development of an easier interface for the gastroenterologists, avoiding the nonintuitive manipulation mapping of the traditional UGI endoscopes. We adapt existing kinematic solutions of multi-backbone continuum robots to model continuum parallel bellow actuators. An actuation compensation strategy is presented and validated to address the pneumatic compressibility through the transmission lines. The design concept was prototyped and tested with a custom control platform. The experimental validation shows that the actuation compensation was demonstrated to significantly improve orientation control of the endoscope end-effector. This paper shows the feasibility of the proposed design and lays the foundation toward clinical scenarios

Sensorless Estimation of the Planar Distal Shape of a Tip-Actuated Endoscope

Traditional endoscopes consist of a flexible body and a steerable tip with therapeutic capability. Although prior endoscopes have relied on operator pushing for actuation, recent robotic concepts have relied on the application of a tip force for guidance. In such case, the body of the endoscope can be passive and compliant; however, the body can have significant effect on mechanics of motion and may require modeling. As the endoscope body's shape is often unknown, we have developed an estimation method to recover the approximate distal shape, local to the endoscope's tip, where the tip position and orientation are the only sensed parameters in the system. We leverage a planar dynamic model and extended Kalman filter to obtain a constant-curvature shape estimate of a magnetically guided endoscope. We validated this estimator in both dynamic simulations and on a physical platform. We then used this estimate in a feed-forward control scheme and demonstrated improved trajectory following. This methodology can enable the use of inverse-dynamic control for the tip-based actuation of an endoscope, without the need for shape sensing

Dual-Continuum Design Approach for Intuitive and Low-Cost Upper Gastrointestinal Endoscopy

Objective: This paper introduces a methodology to design intuitive, low-cost, and portable devices for visual inspection of the upper gastrointestinal tract. Methods: The proposed approach mechanically couples a multi-backbone continuum structure, as the user interface, and a parallel bellows actuator, as the endoscopic tip. Analytical modeling techniques derived from continuum robotics were adopted to describe the endoscopic tip motion from user input, accounting for variations in component size and pneumatic compressibility. The modeling framework was used to improve intuitiveness of user-to-task mapping. This was assessed against a 1:1 target, while ease-of-use was validated using landmark identification tasks performed in a stomach simulator by one expert and ten non-expert users; benchmarked against conventional flexible endoscopy. Pre-clinical validation consisted of comparative trials in in-vivo porcine and human cadaver models. Results: Target mapping was achieved with an average error of $5^\circ$ in bending angle. Simulated endoscopies were performed by an expert user successfully, within a time comparable to conventional endoscopy ( $<$ 1 min difference). Non-experts using the proposed device achieved visualization of the stomach in a shorter time (9 s faster on average) than with a conventional endoscope. The estimated cost is $<$ 10 USD and $<$ 30 USD for disposable and reusable parts, respectively. Significance and Conclusions: Flexible endoscopes are complex and expensive devices, actuated via non-intuitive cable-driven mechanisms. They frequently break, requiring costly repair, and necessitate a dedicated reprocessing facility to prevent cross contamination. The proposed solution is portable, inexpensive, and easy to use, thus lending itself to disposable use by personnel without formal training in flexible endoscopy

Decolonising the curriculum is an ongoing and collective effort: Responding to Townsend (2020) and Gibson and Farias (2020)

This paper responds to Townsend (2020), and Gibson and Farias (2020), who were invited to write commentaries regarding Simaan’s (2020) ‘Decolonising occupational science education through learning activities based on a study from the Global South’. My reply acknowledges work done by scholars in the Global North and South, both in and outside occupational science, that critiques Western-centric hegemony in academia. It recognises the multiple aspects of decolonial work in occupational science education, and its collective and continuous nature. I argue that my objective of stimulating reflections and discussion about decolonising occupational science education and knowledge has been achieved by this collective effort to extend this discourse. Future reflections, research, and activism in this area are of paramount importance if we are to truly decolonise occupational science

Sensitivity Ellipsoids for Force Control of Magnetic Robots With Localization Uncertainty

The navigation of magnetic medical robots typically relies on localizing an actuated, intracorporeal, ferromagnetic body and back-computing a necessary field and gradient that would result in a desired wrench on the device. Uncertainty in this localization degrades the precision of force transmission. Reducing applied force uncertainty may enhance tasks such as in vivo navigation of miniature robots, actuation of magnetically guided catheters, tissue palpation, as well as simply ensuring a bound on forces applied on sensitive tissue. In this paper, we analyze the effects of localization noise on force uncertainty by using sensitivity ellipsoids of the magnetic force Jacobian and introduce an algorithm for uncertainty reduction. We validate the algorithm in both a simulation study and in a physical experiment. In simulation, we observe reductions in estimated force uncertainty by factors of up to 2.8 and 3.1 when using one and two actuating magnets, respectively. On a physical platform, we demonstrate a force uncertainty reduction by a factor of up to 2.5 as measured using an external sensor. Being the first consideration of force uncertainty resulting from noisy localization, this paper provides a strategy for investigators to minimize uncertainty in magnetic force transmission

Probing the Surface of a Laccase for Clues towards the Design of Chemo-Enzymatic Catalysts

Systems featuring a multi-copper oxidase associated with transition-metal complexes can be used to perform oxidation reactions in mild conditions. Here, a strategy is presented for achieving a controlled orientation of a ruthenium–polypyridyl graft at the surface of a fungal laccase. Laccase variants are engineered with unique surface-accessible lysine residues. Distinct ruthenium–polypyridyl-modified laccases are obtained by the reductive alkylation of lysine residues precisely located relative to the T1 copper centre of the enzyme. In none of these hybrids does the presence of the graft compromise the catalytic efficiency of the enzyme on the substrate 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid). Furthermore, the efficiency of the hybrids in olefin oxidation coupled to the light-driven reduction of O2 is highly dependent on the location of the graft at the enzyme surface. Simulated RuII–CuII electron coupling values and distances fit well the observed reactivity and could be used to guide future hybrid designs.L.S. was the recipient of a MinistHre de l’Education Nationale fellowship. This study was supported by grants from the Agence Nationale de la Recherche (ANR-09-BLANC-0176 and ANR-15-CE07-0021-01) and from the Ministerio de EconomÍa, Industria y Competitividad (CTQ2016-79138-R). We thank Elise Courvoisier-Dezord from the Plateforme AVB (AMU): Analyse et Valorisation de la Biodiversit8 and Yolande Charmasson for help in the production of the recombinant enzymes, as well as Pascal Mansuelle and R8gine Lebrun from the Plateforme Prot8omique (CNRSAMU) for help in acquiring mass spectrometry data.Peer ReviewedPostprint (published version