Modelling of red blood cell morphological and deformability changes during in-vitro storage

© 2020 by the authors. Storage lesion is a critical issue facing transfusion treatments, and it adversely affects the quality and viability of stored red blood cells (RBCs). RBC deformability is a key indicator of cell health. Deformability measurements of each RBC unit are a key challenge in transfusion medicine research and clinical haematology. In this paper, a numerical study, inspired from the previous research for RBC deformability and morphology predictions, is conducted for the first time, to investigate the deformability and morphology characteristics of RBCs undergoing storage lesion. This study investigates the evolution of the cell shape factor, elongation index and membrane spicule details, where applicable, of discocyte, echinocyte I, echinocyte II, echinocyte III and sphero-echinocyte morphologies during 42 days of in-vitro storage at 4 °C in saline-adenine-glucose-mannitol (SAGM). Computer simulations were performed to investigate the influence of storage lesion-induced membrane structural defects on cell deformability and its recoverability during optical tweezers stretching deformations. The predicted morphology and deformability indicate decreasing quality and viability of stored RBCs undergoing storage lesion. The loss of membrane structural integrity due to the storage lesion further degrades the cell deformability and recoverability during mechanical deformations. This numerical approach provides a potential framework to study the RBC deformation characteristics under varying pathophysiological conditions for better diagnostics and treatments

The next Generation of Action Ecology: Novel Approaches towards Global Ecological Research

Advances in the acquisition and dissemination of knowledge over the last decade have dramatically reshaped the way that ecological research is conducted. The advent of large, technology-based resources such as iNaturalist, Genbank, or the Global Biodiversity Information Facility (GBIF) allow ecologists to work at spatio-temporal scales previously unimaginable. This has generated a new approach in ecological research: one that relies on large datasets and rapid synthesis for theory testing and development, and findings that provide specific recommendations to policymakers and managers. This new approach has been termed action ecology, and here we aim to expand on earlier definitions to delineate its characteristics so as to distinguish it from related subfields in applied ecology and ecological management. Our new, more nuanced definition describes action ecology as ecological research that is (1) explicitly motivated by the need for immediate insights into current, pressing problems, (2) collaborative and transdisciplinary, incorporating sociological in addition to ecological considerations throughout all steps of the research, (3) technology-mediated, innovative, and aggregative (i.e., reliant on ‘big data\u27), and (4) designed and disseminated with the intention to inform policy and management. We provide tangible examples of existing work in the domain of action ecology, and offer suggestions for its implementation and future growth, with explicit recommendations for individuals, research institutions, and ecological societies

Modelling the deformation behavior of stomatocyte, discocyte and echinocyte red blood cell morphologies during optical tweezers stretching

A coarse-grained (CG) red blood cell (RBC) membrane model is used to investigate the deformation behavior of stomatocyte, discocyte and echinocyte morphologies during optical tweezers stretching. First, the numerically predicted discocyte deformation behavior is validated against analogous experimental observations, and then the numerically predicted stomatocyte and echinocyte deformation behavior is compared to the discocyte deformation behavior. The findings indicate that the CG-RBC membrane model is capable of accurately predicting the deformation behavior of stomatocyte, discocyte and echinocyte RBC morphologies during optical tweezers stretching, and an applicable tool to investigate the evolution of RBC behavior and membrane properties for different morphologies

Traditional knowledge applied to the management of small tank wetland systems in Sri Lanka

The foundation of rice production in the dry zone of Sri Lanka is a hydraulic civilization spanning at least 2,000 years, and based on constructed small irrigation tanks. Dotted across much of the dry zone, and often constituting cascades, the traditional management of these tanks for dry season irrigation water brought together sophisticated engineering skills, deep ecological knowledge and social organisation around the practical need for cooperation and spiritual belief systems. While these small tanks are often referred to with respect to their centrality to irrigating rice, the staple crop, the use of both natural and built elements in managing the tanks and their surrounding landscapes in fact constitute a remarkable multi-functional system that has provided a range of ecosystem services for human well-being. Despite its ancient roots, the ecological principles inherent in the traditional knowledge shaping this system resonate closely with modern concepts around natural resource management such as wise use, sustainability, social ecological systems and green infrastructure

Vegetative growth and yield associated flowering time variation in Sri Lankan rice 'Hondarawala'

Breeding new varieties adaptable for changing climate is an essential need in sustainable rice production. Around 2000 Sri Lankan rice accessions at Plant Genetic Resources Centre (PGRC), Sri Lanka have not been fully characterized for the yield potential and sensitivity to mild photoperiodic differences for days to flowering (DF). DF is a candidate key determinant in yield components in rice and understanding the physiological and molecular nature for DF is important to manipulate crop yield through breeding programmes. The objective of this study was to assess the genetic diversity of 15 Hondarawala accessions from PGRC using selected 37 morphological characters and DF. DF varied from 58-189 days while accession number 3988 did not flower until 200th day of seed germination. Principal Component Analysis (PCA) revealed that four principle components (PA) explained 86.5% of total observed variation. Variation of DF positively associated with most of morphological characters of vegetative growth while a few characters were negatively associated. In the dendogram, 10 clusters formed at rescale distance of 5. Widely variable DF accessions distributed among clusters

Particle-Based Numerical Modelling of Liquid Marbles: Recent Advances and Future Perspectives

A liquid marble is a liquid droplet coated usually with hydrophobic particles that can hold a very small liquid volume without wetting the adjacent surface. This combination gives rise to a set of unique properties such as resistance to contamination, low-friction mobility and flexible manipulation, making them appealing for a myriad of engineering applications including miniature reactors, gas sensing and drug delivery. Despite numerous experimental studies, numerical modelling investigations of liquid marbles are currently underrepresented in the literature, although such investigations can lead to a better understanding of their overall behaviour while overcoming the use of cost- and time-intensive experimental-only procedures. This paper therefore evaluates the capabilities of three well-established and widely-used particle-based numerical frameworks, namely Smoothed Particle Hydrodynamics (SPH)-based approaches, Coarse-Grained (CG)-based approaches and Lattice Boltzmann Method (LBM)-based approaches, to investigate liquid-marble properties and their key applications. Through a comprehensive review of recent advancements, it reveals that these numerical approaches demonstrate promising capabilities of simulating complex multiphysical phenomena involved with liquid-marble systems such as their floatation, coalescence and surface-tension-surface-area relationship. The paper further elaborates on the perspective that benefiting from particle-based numerical and computational techniques, liquid marbles can become an even more effective and exciting platform for many cutting-edge large-scale engineering applications