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1.
Sustain Sci ; 19(2): 595-614, 2024.
Article in English | MEDLINE | ID: mdl-38404522

ABSTRACT

Ambiguity is often recognized as an intrinsic aspect of addressing complex sustainability challenges. Nevertheless, in the practice of transdisciplinary sustainability research, ambiguity is often an 'elephant in the room' to be either side-stepped or reduced rather than explicitly mobilized in pursuit of solutions. These responses threaten the salience and legitimacy of sustainability science by masking the pluralism of real-world sustainability challenges and how research renders certain frames visible and invisible. Critical systems thinking (CST) emerged from the efforts of operational researchers to address theoretical and practical aspects of ambiguity. By adapting key concepts, frameworks, and lessons from CST literature and case studies, this paper aims to establish (1) an expansive conceptualization of ambiguity and (2) recommendations for operationalizing ambiguity as a valuable means of addressing sustainability challenges. We conceptualize ambiguity as an emergent feature of the simultaneous and interacting boundary processes associated with being, knowing, and intervening in complex systems, and propose Reflexive Boundary Critique (RBC) as a novel framework to help navigate these boundary processes. Our characterization of ambiguity acknowledges the boundary of a researcher's subjective orientation and its influence on how ambiguity is exposed and mediated in research (being), characterizes knowledge as produced through the process of making boundary judgments, generating a partial, contextual, and provisional frame (knowing), and situates a researcher as part of the complexity they seek to understand, rendering any boundary process as a form of intervention that reinforces or marginalizes certain frames and, in turn, influences action (intervening). Our recommendations for sustainability scientists to operationalize ambiguity include (1) nurturing the reflexive capacities of transdisciplinary researchers to navigate persistent ambiguity (e.g., using our proposed framework of RBC), and (2) grappling with the potential for and consequences of theoretical incommensurability and discordant pluralism. Our findings can help sustainability scientists give shape to and embrace ambiguity as a fundamental part of rigorous sustainability science.

2.
Sustain Sci ; 16(2): 703-708, 2021.
Article in English | MEDLINE | ID: mdl-33686348

ABSTRACT

Enduring sustainability challenges requires a new model of collective leadership that embraces critical reflection, inclusivity and care. Leadership collectives can support a move in academia from metrics to merits, from a focus on career to care, and enact a shift from disciplinary to inter- and trans-disciplinary research. Academic organisations need to reorient their training programs, work ethics and reward systems to encourage collective excellence and to allow space for future leaders to develop and enact a radically re-imagined vision of how to lead as a collective with care for people and the planet. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11625-021-00909-y.

3.
Ambio ; 50(7): 1304-1312, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33566331

ABSTRACT

The interdependence of social and ecological processes is broadly acknowledged in the pursuit to enhance human wellbeing and prosperity for all. Yet, development interventions continue to prioritise economic development and short-term goals with little consideration of social-ecological interdependencies, ultimately undermining resilience and therefore efforts to deliver development outcomes. We propose and advance a coevolutionary perspective for rethinking development and its relationship to resilience. The perspective rests on three propositions: (1) social-ecological relationships coevolve through processes of variation, selection and retention, which are manifest in practices; (2) resilience is the capacity to filter practices (i.e. to influence what is selected and retained); and (3) development is a coevolutionary process shaping pathways of persistence, adaptation or transformation. Development interventions affect and are affected by social-ecological relationships and their coevolutionary dynamics, with consequences for resilience, often with perverse outcomes. A coevolutionary approach enables development interventions to better consider social-ecological interdependencies and dynamics. Adopting a coevolutionary perspective, which we illustrate with a case on agricultural biodiversity, encourages a radical rethinking of how resilience and development are conceptualised and practiced across global to local scales.


Subject(s)
Biodiversity , Social Environment , Humans
4.
Environ Dev Sustain ; 21(5): 2183-2224, 2019.
Article in English | MEDLINE | ID: mdl-32684800

ABSTRACT

In the Pamir Mountains of Eastern Tajikistan, the clearance of mountain forests to provide fuelwood for an increasing population is a major source of environmental degradation. International development organisations have implemented joint forestry management institutions to help restore once-forested mountainous regions, but the success of these institutions has been highly variable. This study uses a multi-method approach, drawing on institutional analysis supported by Elinor Ostrom's design principles and social-ecological system framework in combination with resilience thinking to help understand why some communities in Tajikistan manage their forests more sustainably than others. The application of the design principles provided helpful guidance for practitioners implementing joint forestry management. The social-ecological system analysis revealed both 'history of use' and 'tenant density' as positively associated with forest condition. However, we also identify limitations of snapshot social-ecological assessments. In particular, we illustrate the critical importance of considering historical legacy effects, such as externally imposed centralised governance regimes (that characterise many post-Soviet states) in attempts to understand current management practices. Our work shows how a more nuanced understanding of institutional change and inertia can be achieved by adopting a resilience approach to institutional analysis, focusing on the importance of reorganisation. Lessons learned from our analysis should be widely applicable to common pool resource management in other semi-arid forested landscapes as well as in regions with a strong centralised governance legacy.

5.
Sustain Sci ; 13(1): 191-204, 2018.
Article in English | MEDLINE | ID: mdl-30147779

ABSTRACT

The establishment of interdisciplinary Master's and PhD programs in sustainability science is opening up an exciting arena filled with opportunities for early-career scholars to address pressing sustainability challenges. However, embarking upon an interdisciplinary endeavor as an early-career scholar poses a unique set of challenges: to develop an individual scientific identity and a strong and specific methodological skill-set, while at the same time gaining the ability to understand and communicate between different epistemologies. Here, we explore the challenges and opportunities that emerge from a new kind of interdisciplinary journey, which we describe as 'undisciplinary.' Undisciplinary describes (1) the space or condition of early-career researchers with early interdisciplinary backgrounds, (2) the process of the journey, and (3) the orientation which aids scholars to address the complex nature of today's sustainability challenges. The undisciplinary journey is an iterative and reflexive process of balancing methodological groundedness and epistemological agility to engage in rigorous sustainability science. The paper draws upon insights from a collective journey of broad discussion, reflection, and learning, including a survey on educational backgrounds of different generations of sustainability scholars, participatory forum theater, and a panel discussion at the Resilience 2014 conference (Montpellier, France). Based on the results from this diversity of methods, we suggest that there is now a new and distinct generation of sustainability scholars that start their careers with interdisciplinary training, as opposed to only engaging in interdisciplinary research once strong disciplinary foundations have been built. We further identify methodological groundedness and epistemological agility as guiding competencies to become capable sustainability scientists and discuss the implications of an undisciplinary journey in the current institutional context of universities and research centers. In this paper, we propose a simple framework to help early-career sustainability scholars and well-established scientists successfully navigate what can sometimes be an uncomfortable space in education and research, with the ultimate aim of producing and engaging in rigorous and impactful sustainability science.

6.
Sci Adv ; 3(5): e1603043, 2017 May.
Article in English | MEDLINE | ID: mdl-28508077

ABSTRACT

The poverty trap concept strongly influences current research and policy on poverty alleviation. Financial or technological inputs intended to "push" the rural poor out of a poverty trap have had many successes but have also failed unexpectedly with serious ecological and social consequences that can reinforce poverty. Resilience thinking can help to (i) understand how these failures emerge from the complex relationships between humans and the ecosystems on which they depend and (ii) navigate diverse poverty alleviation strategies, such as transformative change, that may instead be required. First, we review commonly observed or assumed social-ecological relationships in rural development contexts, focusing on economic, biophysical, and cultural aspects of poverty. Second, we develop a classification of poverty alleviation strategies using insights from resilience research on social-ecological change. Last, we use these advances to develop stylized, multidimensional poverty trap models. The models show that (i) interventions that ignore nature and culture can reinforce poverty (particularly in agrobiodiverse landscapes), (ii) transformative change can instead open new pathways for poverty alleviation, and (iii) asset inputs may be effective in other contexts (for example, where resource degradation and poverty are tightly interlinked). Our model-based approach and insights offer a systematic way to review the consequences of the causal mechanisms that characterize poverty traps in different agricultural contexts and identify appropriate strategies for rural development challenges.

7.
Sustain Sci ; 11(6): 877-889, 2016.
Article in English | MEDLINE | ID: mdl-30174745

ABSTRACT

Social-ecological (SE) traps refer to persistent mismatches between the responses of people, or organisms, and their social and ecological conditions that are undesirable from a sustainability perspective. Until now, the occurrence of SE traps is primarily explained from a lack of adaptive capacity; not much attention is paid to other causal factors. In our article, we address this concern by theorizing the variety of human responses to SE traps and the effect of these responses on trap dynamics. Besides (adaptive) capacities, we theorize desires, abilities and opportunities as important additional drivers to explain the diversity of human responses to traps. Using these theoretical concepts, we construct a typology of human responses to SE traps, and illustrate its empirical relevance with three cases of SE traps: Swedish Baltic Sea fishery; amaXhosa rural livelihoods; and Pamir smallholder farming. We conclude with a discussion of how attention to the diversity in human response to SE traps may inform future academic research and planned interventions to prevent or dissolve SE traps.

8.
Mult Scler J Exp Transl Clin ; 1: 2055217315609629, 2015.
Article in English | MEDLINE | ID: mdl-28607707

ABSTRACT

BACKGROUND: Cognitive impairment represents a critical unmet treatment need in multiple sclerosis (MS). Cognitive remediation is promising but traditionally requires multiple clinic visits to access treatment. Computer-based programs provide remote access to intensive and individually-adapted training. OBJECTIVE: Our goal was to develop a protocol for remotely-supervised cognitive remediation that enables individuals with MS to participate from home while maintaining the standards for clinical study. METHODS: MS participants (n = 20) were randomized to either an active cognitive remediation program (n = 11) or a control condition of ordinary computer games (n = 9). Participants were provided study laptops to complete training for five days per week over 12 weeks, targeting a total of 30 hours. Treatment effects were measured with composite change via scores of a repeated neuropsychological battery. RESULTS: Compliance was high with an average of 25.0 hours of program use (80% of the target) and did not differ between conditions (25.7 vs. 24.2 mean hours, p = 0.80). The active vs. control participants significantly improved in both the cognitive measures (mean composite z-score change of 0.46 ± 0.59 improvement vs. -0.14 ± 0.48 decline, p = 0.02) and motor tasks (mean composite z-score change of 0.40 ± 0.71improvement vs. -0.64 ± 0.73 decline, p = 0.005). CONCLUSIONS: Remotely-supervised cognitive remediation is feasible for clinical study with potential for meaningful benefit in MS.

9.
Indian J Exp Biol ; 45(1): 18-24, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17249323

ABSTRACT

Ultrasonic waves of 1-15 MHz frequencies easily propagate through soft biological tissues, thus providing qualitative and quantitative information on mechanical and flow properties of blood and red blood cell (RBC) suspensions. Two types of techniques allow to investigate blood behaviors: echographic devices via amplitude detection and Doppler effect based devices via frequency detection of the ultrasonic signal. When ever B mode serves to construct images of tissue slabs from the ultrasonic backscattering coefficient and can give qualitative information on the mechanical properties of blood, A-mode allows to quantify the ultrasonic backscattering coefficient. Ultrasonic Doppler modes also provide both qualitative and quantitative information on blood flow velocity: continuous and pulsed Doppler modes provide curves of blood flow versus time when color Doppler and power Doppler imaging visualize blood flowing in human vessels. Association of echographic and Doppler modes to investigate simultaneously structure and velocity of blood is commercially available. Some examples of results given by such ultrasonic techniques that contribute to characterize, both in vitro and in vivo, structure and flow properties of blood or red blood cell (RBC) suspensions are presented.


Subject(s)
Blood Flow Velocity , Blood Viscosity , Erythrocyte Aggregation , Ultrasonography, Doppler , Hemorheology , Humans
10.
Biophys J ; 87(4): 2322-34, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15454433

ABSTRACT

The shear flow dynamics of reversible red cell aggregates in dense suspensions were investigated by ultrasound scattering, to study the shear disruption processes of Rayleigh clusters and examine the effective mean field approximation used in microrheological models. In a first section, a rheo-acoustical model, in the Rayleigh scattering regime, is proposed to describe the shear stress dependence of the low frequency scattered power in relation to structural parameters. The fractal scattering regime characterizing the anisotropic scattering from flocs of size larger than the ultrasound wavelength is further discussed. In the second section, we report flow-dependent changes in the low-frequency scattering coefficient in a plane-plane flow geometry to analyze the shear disruption processes of hardened or deformable red cell aggregates in neutral dextran polymer solution. Rheo-acoustical experiments are examined on the basis of the rheo-acoustical model and the effective medium approximation. The ability of ultrasound scattering technique to determine the critical disaggregation shear stress and to give quantitative information on particle surface adhesive energy is analyzed. Lastly, the shear-thinning behavior of weakly aggregated hardened or deformable red cells is described.


Subject(s)
Algorithms , Erythrocyte Aggregation/physiology , Erythrocytes/diagnostic imaging , Erythrocytes/physiology , Image Interpretation, Computer-Assisted/methods , Models, Cardiovascular , Rheology/methods , Blood Flow Velocity/physiology , Cells, Cultured , Fractals , Humans , Scattering, Radiation , Shear Strength , Tomography, Optical , Ultrasonography
11.
Clin Hemorheol Microcirc ; 30(3-4): 345-52, 2004.
Article in English | MEDLINE | ID: mdl-15258365

ABSTRACT

Ultrasound scattering technique is used to investigate dynamics of reversible fractal aggregates in dense suspensions and analyze shear break-up processes of Rayleigh fractal clusters. On the basis of an homogenous fractal flocculation and the hybrid scattering model in the Rayleigh scattering regime, a first order expression of the ultrasound scattering cross-sectional area per unit of volume (backscattering coefficient) is derived for a dense distribution of correlated Rayleigh fractal clusters. From the scaling laws for shear break-up of reversible aggregates in concentrated suspensions, a rheo-acoustical study is then proposed to describe the shear stress dependence of the low frequency scattered power per unit of volume. In a second part, experimental flow dependent changes of the ultrasound backscattering coefficient in a plane-plane flow geometry were reported to analyze shear break-up processes of hardened or deformable red cell aggregates in polymer solution (neutral dextran polymer). Rheo-acoustical experiments were examined within the framework of the effective mean field approximation and the proposed rheo-acoustical model. The ability of ultrasound scattering to determine the critical disaggregation shear stress inducing a complete disaggregation and to give quantitative information on particle surface adhesive energy are finally analyzed.


Subject(s)
Erythrocyte Aggregation/physiology , Erythrocytes/diagnostic imaging , Fractals , Hemorheology , Humans , Models, Biological , Stress, Mechanical , Ultrasonography
12.
J Acoust Soc Am ; 107(3): 1715-26, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10738823

ABSTRACT

Shear-induced disruption of reversible aggregates or clusters in a concentrated suspension is investigated by ultrasound backscattering in the low shear regime. Fractal aggregates are considered as non-Brownian scatterers much smaller than the wavelength with acoustic properties close to those of the surrounding liquid, so that the attenuation of the coherent field is weak and multiple scattering can be neglected. The concept of variance in local particle volume fraction is used to deduce a first-order expression of the ultrasound scattering cross section per unit volume for Rayleigh scatterers in a dense suspension. On the basis of a scaling law for the shear-induced disruption of aggregates, the shear stress dependence of the ultrasonic scattered intensity from a dense suspension of clusters is derived. In a second part, the shear breakup of hardened red blood cell aggregates is investigated in plane-plane flow geometry by ultrasound scattering. Rheo-acoustical experiments are analyzed within the framework of the self-consistent field approximation and the scaling laws currently used in microrheological models. Finally, the ability of ultrasonic, light reflectometry and viscometry methods to provide quantitative information about red blood cell aggregation and membrane adhesiveness is discussed.


Subject(s)
Acoustics , Erythrocytes/diagnostic imaging , Erythrocytes/physiology , Ultrasonics , Humans , Models, Biological , Plethysmography, Impedance/methods , Ultrasonography
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