The thesis examines the social and economic implications of large-scale agribusiness expansion in Indonesia by analyzing how this economic system, as it is envisioned and materialised, reshapes livelihood possibilities. Based on original interviews with oil palm plantation workers, plantation company officials, smallholders, and on secondary research, this thesis scrutinises the forms of knowledge and practices that constitute large-scale oil palm agribusiness. While oil palm agribusiness produces economic opportunities for groups of individuals from certain social categories, it constrains the prospects of others in systematic ways. Oil palm agribusiness, as a project and as a set of practices, is deployed by a broad range of economic actors at different scales in an attempt to govern access to resources. However, the power of oil palm companies and investors over land, labour, and value is contested and negotiated by workers and smallholders who engage creatively with this economy. The thesis shows that oil palm agribusiness forms a field of power that produces specific subjectivities which transform the meanings and constraints related to this mode of production. The first part of the thesis (chapters 2 and 3) identifies the objectives pursued by those who plan and envision oil palm agribusiness. I emphasise that oil palm agribusiness serves a number of often competing and shifting aims that range from capital accumulation to welfare provision. The second part of the thesis (chapters 4 and 5) demonstrates how the modes of visioning examined in the first part of the thesis produce a broad set of material conditions for populations. I analyse the ways in which these conditions are constantly reshaped by everyday power relations and articulated around the value of labour and land. Based on ethnographic fieldwork that I conducted in West Kalimantan, Lombok, and Nias, these chapters shed light on the lived geographies of labour and the livelihood strategies used by individuals and social groups in the space of oil palm agribusiness.

The thesis examines the social and economic implications of large-scale agribusiness expansion in Indonesia by analyzing how this economic system, as it is envisioned and materialised, reshapes livelihood possibilities. Based on original interviews with oil palm plantation workers, plantation company officials, smallholders, and on secondary research, this thesis scrutinises the forms of knowledge and practices that constitute large-scale oil palm agribusiness. While oil palm agribusiness produces economic opportunities for groups of individuals from certain social categories, it constrains the prospects of others in systematic ways. Oil palm agribusiness, as a project and as a set of practices, is deployed by a broad range of economic actors at different scales in an attempt to govern access to resources. However, the power of oil palm companies and investors over land, labour, and value is contested and negotiated by workers and smallholders who engage creatively with this economy. The thesis shows that oil palm agribusiness forms a field of power that produces specific subjectivities which transform the meanings and constraints related to this mode of production. The first part of the thesis (chapters 2 and 3) identifies the objectives pursued by those who plan and envision oil palm agribusiness. I emphasise that oil palm agribusiness serves a number of often competing and shifting aims that range from capital accumulation to welfare provision. The second part of the thesis (chapters 4 and 5) demonstrates how the modes of visioning examined in the first part of the thesis produce a broad set of material conditions for populations. I analyse the ways in which these conditions are constantly reshaped by everyday power relations and articulated around the value of labour and land. Based on ethnographic fieldwork that I conducted in West Kalimantan, Lombok, and Nias, these chapters shed light on the lived geographies of labour and the livelihood strategies used by individuals and social groups in the space of oil palm agribusiness.

For older adults, functional independent mobility is essential to well-being. Many care home residents have physical and cognitive impairments and use wheelchairs. Residents with difficulty self-propelling manual wheelchairs may benefit from power mobility; however, those with cognitive impairments may be precluded because of the potential for injury. My research goals were to apply novel power wheelchair technology to enable safe, independent mobility. Technology was developed to examine the value and implications of power mobility for residents with restricted mobility and mild or moderate cognitive impairments. The first study tested a prototype anti-collision wheelchair with a contact sensor skirt. Six single subject studies were completed. Distances travelled in manual and anti-collision wheelchairs were compared. Observational and interview data were collected. Focus groups (37 staff) and interviews (18 staff, six other residents, one spouse) were performed. Three of six residents were able or had potential to operate the prototype. One resident chose to use it beyond the study, and his mobility and well-being improved. Case analyses showed factors limiting prototype acceptance. Residents were unsatisfied with the appearance and slow speed, and found the interface frustrating to operate because of inadequate feedback. Social isolation and reduced autonomy restricted independence achievable with technology. Socialization and affective benefits of mobility were demonstrated in one case where prototype use was continually assisted. Residents and staff supported the anti-collision concept. On observation, the prototype compensated for absent or delayed responses of residents to obstacles below sensors and decreased injury risk. However, full sensor coverage of the environment was needed. The second study addressed acceptance and interface usability issues. A simulated collision-avoidance wheelchair with a multimodal feedback interface was evaluated. The interface provided audio, visual and haptic feedback to guide navigation away from obstacles. Through observations, interviews and questionnaires, five residents evaluated the device. High device acceptance and usability were found. The device was easy to use and assisted with performance of indoor mobility goals. Further research is necessary before power wheelchairs with new features are available for users; however, these results could play a fundamental role in shaping technology development and mobility interventions for this neglected population.

For older adults, functional independent mobility is essential to well-being. Many care home residents have physical and cognitive impairments and use wheelchairs. Residents with difficulty self-propelling manual wheelchairs may benefit from power mobility; however, those with cognitive impairments may be precluded because of the potential for injury. My research goals were to apply novel power wheelchair technology to enable safe, independent mobility. Technology was developed to examine the value and implications of power mobility for residents with restricted mobility and mild or moderate cognitive impairments. The first study tested a prototype anti-collision wheelchair with a contact sensor skirt. Six single subject studies were completed. Distances travelled in manual and anti-collision wheelchairs were compared. Observational and interview data were collected. Focus groups (37 staff) and interviews (18 staff, six other residents, one spouse) were performed. Three of six residents were able or had potential to operate the prototype. One resident chose to use it beyond the study, and his mobility and well-being improved. Case analyses showed factors limiting prototype acceptance. Residents were unsatisfied with the appearance and slow speed, and found the interface frustrating to operate because of inadequate feedback. Social isolation and reduced autonomy restricted independence achievable with technology. Socialization and affective benefits of mobility were demonstrated in one case where prototype use was continually assisted. Residents and staff supported the anti-collision concept. On observation, the prototype compensated for absent or delayed responses of residents to obstacles below sensors and decreased injury risk. However, full sensor coverage of the environment was needed. The second study addressed acceptance and interface usability issues. A simulated collision-avoidance wheelchair with a multimodal feedback interface was evaluated. The interface provided audio, visual and haptic feedback to guide navigation away from obstacles. Through observations, interviews and questionnaires, five residents evaluated the device. High device acceptance and usability were found. The device was easy to use and assisted with performance of indoor mobility goals. Further research is necessary before power wheelchairs with new features are available for users; however, these results could play a fundamental role in shaping technology development and mobility interventions for this neglected population.

Le vieillissement démographique augmente rapidement la représentation des personnes âgées de plus de 50 ans parmi les utilisateurs d’aides à la mobilité motorisées (AMMs), telles que le fauteuil roulant motorisé et le quadriporteur. Le but général de la thèse est de rendre compte d’une démarche d’analyse des effets des AMMs au cours des premiers 18 mois d’utilisation chez les adultes d’âge moyen et les aînés. Notre question de recherche concerne la nature et l'importance des effets sur le fonctionnement, la pertinence sociale et le bien-être subjectif, ainsi que les liens entre les divers facteurs impliqués dans leur impact optimal. La thèse s’articule en trois volets, synthétique, méthodologique et analytique, dont les principaux résultats sont présentés dans quatre articles scientifiques. Le volet synthétique comprend une recension systématique qui révèle la représentation marginale des personnes âgées de plus de 50 ans dans les publications scientifiques sur les effets des AMMs et le faible niveau de preuve dans ce champ d’études. Les travaux liés à ce volet proposent également un cadre d’analyse reliant l’intention d’utiliser l’AMM, les habitudes de déplacements, les dimensions d’effets des AMMs sur le fonctionnement, la pertinence sociale et le bien-être subjectif, ainsi que quatre catégories de cofacteurs associés à l’utilisation (personne, aide technique, intervention, environnement). Le volet méthodologique assemble un dispositif de mesure comprenant 5 questionnaires et 18 indicateurs arrimés au cadre d’analyse et démontre l’applicabilité de l’ensemble des questionnaires pour une administration téléphonique. La validation transculturelle de deux questionnaires implique deux études réalisées auprès d’utilisateurs d’AMMs âgés de 50 à 84 ans (n=45). Ces travaux confirment la fidélité test-retest et l’équivalence des questionnaires traduits avec la version d’origine. Finalement, le volet analytique se concentre sur l’étude des habitudes de déplacements chez 3 cohortes (n=116) de personnes âgées de 50 à 89 ans, recrutées en fonction du stade d’utilisation de l’AMM. Les résultats suggèrent une amélioration de l’aire de mobilité après l’utilisation initiale ou long terme de l’AMM en comparaison avec une cohorte en attente de l’AMM, ainsi qu’une augmentation significative de la fréquence des déplacements autour du domicile et dans le voisinage. Trois facteurs associés à une aire de mobilité optimale, à savoir le genre, la nature des objectifs de participation de l’utilisateur et le type d’appareil utilisé, sont identifiés par des analyses de régression linéaires contrôlant pour l’âge. La thèse soutient l’importance de tenir compte de l’environnement et d’une combinaison de facteurs reliés à la personne et à l’aide technique pour saisir les effets des AMMs au cours des premiers mois d’utilisation. Ces résultats ouvrent la voie au suivi systématique des utilisateurs d’AMMs par les professionels de réadaptation, puisqu’ils confirment l’utilité du dispositif pour en mesurer les effets et ciblent les déterminants de la mobilité des utilisateurs d’AMMs âgés de plus de 50 ans. / Mobility-related subsidy programs are being challenged by the aging of the population as adults aged over 50 years become the most prevalent users of power mobility devices (PMDs), such as power wheelchairs and scooters. The thesis examines the impacts of PMDs for middle-aged and older adults during the first 18 months of use. Our research question concerns the nature and magnitude of outcomes pertaining to effectiveness, social significance and subjective well-being, as well as the factors associated with outcomes. The thesis comprises three sections: conceptual, methodological and analytical. The main results are presented in four manuscripts. The conceptual section includes a systematic review that reveals the limited coverage and low level of evidence of PMD outcomes for middle-aged and older adults. Moreover, this section supports a conceptual framework linking intention to use the PMD, mobility habits, three dimensions of outcomes (effectiveness, social significance, subjective well-being) and four categories of co-factors asociated with the use of assistive technology (person, assistive device, intervention, environment). The methodological section assembled 5 questionnaires and 18 indicators, matched to the conceptual framework, and verified their applicability for a telephone administration. Two questionnaires required transcultural validation studies with PMD users (n=45, age 50-84 years) that confirmed the test-retest reliability and the equivalence of the questionnaires with the original versions. Finally, the analytical section examined the impact of PMDs on 3 cohorts (n=116, age 50-89 years), recruited as a function of stage of usage, and explored key factors asociated with greater life-space mobility. Cohort comparisons showed significantly greater life-space mobility for initial and long term users than for the reference group waiting for the PMD. Moreover, frequency of outings was higher for PMD users in the neighbourhood and around home. Age-adjusted linear regression analyses found greater life-space mobility associated with gender, the nature of PMD activities and device type. The thesis supports considering the environment and a combination of personal and device factors to appreciate PMD outcomes during the first months of use. The results are useful for rehabilitation services as they confirm the utility of following up PMD outcomes and identify key determinants of mobility for middle-aged and older PMD users.

Le vieillissement démographique augmente rapidement la représentation des personnes âgées de plus de 50 ans parmi les utilisateurs d’aides à la mobilité motorisées (AMMs), telles que le fauteuil roulant motorisé et le quadriporteur. Le but général de la thèse est de rendre compte d’une démarche d’analyse des effets des AMMs au cours des premiers 18 mois d’utilisation chez les adultes d’âge moyen et les aînés. Notre question de recherche concerne la nature et l'importance des effets sur le fonctionnement, la pertinence sociale et le bien-être subjectif, ainsi que les liens entre les divers facteurs impliqués dans leur impact optimal. La thèse s’articule en trois volets, synthétique, méthodologique et analytique, dont les principaux résultats sont présentés dans quatre articles scientifiques. Le volet synthétique comprend une recension systématique qui révèle la représentation marginale des personnes âgées de plus de 50 ans dans les publications scientifiques sur les effets des AMMs et le faible niveau de preuve dans ce champ d’études. Les travaux liés à ce volet proposent également un cadre d’analyse reliant l’intention d’utiliser l’AMM, les habitudes de déplacements, les dimensions d’effets des AMMs sur le fonctionnement, la pertinence sociale et le bien-être subjectif, ainsi que quatre catégories de cofacteurs associés à l’utilisation (personne, aide technique, intervention, environnement). Le volet méthodologique assemble un dispositif de mesure comprenant 5 questionnaires et 18 indicateurs arrimés au cadre d’analyse et démontre l’applicabilité de l’ensemble des questionnaires pour une administration téléphonique. La validation transculturelle de deux questionnaires implique deux études réalisées auprès d’utilisateurs d’AMMs âgés de 50 à 84 ans (n=45). Ces travaux confirment la fidélité test-retest et l’équivalence des questionnaires traduits avec la version d’origine. Finalement, le volet analytique se concentre sur l’étude des habitudes de déplacements chez 3 cohortes (n=116) de personnes âgées de 50 à 89 ans, recrutées en fonction du stade d’utilisation de l’AMM. Les résultats suggèrent une amélioration de l’aire de mobilité après l’utilisation initiale ou long terme de l’AMM en comparaison avec une cohorte en attente de l’AMM, ainsi qu’une augmentation significative de la fréquence des déplacements autour du domicile et dans le voisinage. Trois facteurs associés à une aire de mobilité optimale, à savoir le genre, la nature des objectifs de participation de l’utilisateur et le type d’appareil utilisé, sont identifiés par des analyses de régression linéaires contrôlant pour l’âge. La thèse soutient l’importance de tenir compte de l’environnement et d’une combinaison de facteurs reliés à la personne et à l’aide technique pour saisir les effets des AMMs au cours des premiers mois d’utilisation. Ces résultats ouvrent la voie au suivi systématique des utilisateurs d’AMMs par les professionels de réadaptation, puisqu’ils confirment l’utilité du dispositif pour en mesurer les effets et ciblent les déterminants de la mobilité des utilisateurs d’AMMs âgés de plus de 50 ans. / Mobility-related subsidy programs are being challenged by the aging of the population as adults aged over 50 years become the most prevalent users of power mobility devices (PMDs), such as power wheelchairs and scooters. The thesis examines the impacts of PMDs for middle-aged and older adults during the first 18 months of use. Our research question concerns the nature and magnitude of outcomes pertaining to effectiveness, social significance and subjective well-being, as well as the factors associated with outcomes. The thesis comprises three sections: conceptual, methodological and analytical. The main results are presented in four manuscripts. The conceptual section includes a systematic review that reveals the limited coverage and low level of evidence of PMD outcomes for middle-aged and older adults. Moreover, this section supports a conceptual framework linking intention to use the PMD, mobility habits, three dimensions of outcomes (effectiveness, social significance, subjective well-being) and four categories of co-factors asociated with the use of assistive technology (person, assistive device, intervention, environment). The methodological section assembled 5 questionnaires and 18 indicators, matched to the conceptual framework, and verified their applicability for a telephone administration. Two questionnaires required transcultural validation studies with PMD users (n=45, age 50-84 years) that confirmed the test-retest reliability and the equivalence of the questionnaires with the original versions. Finally, the analytical section examined the impact of PMDs on 3 cohorts (n=116, age 50-89 years), recruited as a function of stage of usage, and explored key factors asociated with greater life-space mobility. Cohort comparisons showed significantly greater life-space mobility for initial and long term users than for the reference group waiting for the PMD. Moreover, frequency of outings was higher for PMD users in the neighbourhood and around home. Age-adjusted linear regression analyses found greater life-space mobility associated with gender, the nature of PMD activities and device type. The thesis supports considering the environment and a combination of personal and device factors to appreciate PMD outcomes during the first months of use. The results are useful for rehabilitation services as they confirm the utility of following up PMD outcomes and identify key determinants of mobility for middle-aged and older PMD users.