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Key research themes
1. How does size and scaling affect nutrient uptake and growth dynamics in phytoplankton communities?
This research theme investigates the mechanistic and physiological effects of phytoplankton cell size on nutrient uptake kinetics, growth rates, and carbon fixation, incorporating physiological trade-offs and environmental resource availability. It aims to understand how size-dependent traits influence ecological community structure and biogeochemical function, especially under varying light and nutrient conditions in marine ecosystems.
Key finding: This paper presents a novel model that integrates a size-based framework accounting for extracellular diffusive limitation with an optimal resource allocation trade-off to explain the half-saturation constant for nitrate... Read more
Key finding: Using physiological models, this study shows that phytoplankton growth rate scaling exponents vary from about 3/4 under resource saturation to between 1/3 and 2/3 under nutrient or light limitation, reflecting the shifting... Read more
Key finding: Empirical analysis reveals near-isometric scaling of carbon fixation rates with cell size across oceanic ecosystems, with biomass-specific photosynthesis rates largely independent of size. Contrasting size-abundance scaling... Read more
2. How can scaling principles elucidate the growth and structure of complex networked systems?
This theme centers on the origins and mechanisms underlying observed super-linear and sub-linear scaling behaviors in the growth of complex, spatially embedded networks, including online communities, urban systems, citation networks, and ecological webs. The focus is on unified geometric network models that capture how spatial constraints and node interactions produce characteristic scaling laws, offering analytical insight into network dynamics and aggregation.
Key finding: The proposed Spatial-Constrained Attachment (SCA) geometric network model, parameter-free and embedded in Euclidean space of arbitrary dimension, simultaneously reproduces super-linear scaling of links/activities and... Read more
3. How do concepts of scale and scaling influence the implementation of innovations in mathematics education research?
This research area addresses the conceptual clarity and operational definitions of scale and scaling in the context of large-scale implementation of educational innovations, especially in mathematics education. It explores dimensions such as spread, sustainability, depth, and ownership shifts, and distinguishes small, medium, and large-scale implementations based on organizational, material, and contact factors to better characterize and guide scaling efforts.
Key finding: Using a Delphi-inspired method combined with literature review, this study elucidates varying expert understandings of scale and scaling, moving beyond simplistic notions of expansion in participant numbers. It... Read more
4. What are the risks and limitations inherent in scaling big capital investments and infrastructure projects?
This theme investigates the fragility associated with large-scale capital investments, challenging the assumption that bigger projects inherently yield better economies of scale and scope. It highlights how scaling increases non-linear exposure to uncertainties leading to poor financial and operational outcomes. The work emphasizes a critical assessment of where scaling adds value versus where it leads to disproportionate risks, with implications for project leadership and management.
Key finding: This paper theorizes the systematic fragility of large capital investments, showing that despite economies of scale, big projects incur disproportionate uncertainty exposures that lead to frequent negative net present values... Read more