Optical guided wave devices can experience crosstalk and mode-switching in the presence of ionizing radiation. This technical note discusses the responses of LiTaO{sub 3} and LiNbO{sub 3}:Ti directional coupler waveguides to exposures of linearly accelerated electrons. A comparison of the waveguides in terms of sensitivity to the ionizing radiation is made.
Abstract Mitochondria, apart from being the powerhouses of our cells, are key players in cellular metabolism and homeostasis. As a consequence, the core bioenergetics and metabolism of mitochondria are well studied considering the role that dysregulated mitochondrial metabolism plays in disease. Flux Balance Analysis, used in conjunction with metabolic model reconstructions is a powerful computational tool that predicts metabolism. The resulting quantitative descriptions of metabolic dysregulation not only allows current hypotheses to be tested in silico , but can also lead to novel model driven hypotheses that can be experimentally verified. Several metabolic reconstructions for human and mouse metabolism exist, but no model specific to mouse mitochondrial metabolism exists. Here, we have created a mouse-specific mitochondrial metabolic model, mitoMouse, which is based on the high-quality human MitoCore mode. MitoMouse contains 390 genes and 445 metabolites involved in 560 unique reactions, is able to model central carbon metabolism and has been extended to contain reduction of the CoQ complex of Oxidative Phosphorylation by the enzyme DHODH. MitoMOuse was validated to accurately model the important metabolic switch involving CoQ reduction resulting from increased malate import, as recently shown in mouse cardiac tissue. We expect this model to be of immense interest and relevance to researchers working on murine mitochondrial metabolism.
The transformation to a resource-circular bio-economy offers a mechanism to mitigate climate change and environmental degradation. As advanced bioeconomy components, biorenewables derived from terrestrial, aquatic biomass and waste resources are expected to play significant roles over the next decades. This study provides an overview of potential biomass resources ranging from higher plant species to phototrophic microbial cluster, and their fundamental photosynthesis processes as well as biogeochemical carbon cycles involved in ecosystems. The review reflects empirical advances in conversion technologies and processes to manufacture value-added biorenewables from biomass and waste resources. The nexus perspective of resource-biorenewable-waste has been analysed to understand their interdependency and wider interaction with environmental resources and ecosystems. We further discussed the systems perspectives of biorenewables to develop fundamental understanding of resource flows and carbon cycles across biorenewable subsystems and highlight their spatial and temporal variability. Our in-depth review suggested the system challenges of biorenewable, which are subject to nonlinearity, variability and complexity. To unlock such system complexity and address the challenges, a whole systems approach is necessary to develop fundamental understanding, design novel biorenewable solutions. Our review reflects recent advances and prospects of computational methods for biorenewable systems modelling. This covers the development and applications of first principle models, process design, quantitative evaluation of sustainability and ecosystem services and mathematical optimisation to improve design, operation and planning of processes and develop emerging biorenewable systems. Coupling these advanced computational methods, a whole systems approach enables a multi-scale modelling framework to inherently link the processes and subsystems involved in biomass ecosystems and biorenewable manufacturing. Reviewing modelling advances, our study provides insights into the emerging opportunities in biorenewable research and highlights the frontier research directions, which have the potential to impact biorenewable sector sustainability.
Cells of the green alga Chlamydomonas reinhardtii cultured in the presence of acetate perform mixotrophic growth, involving both photosynthesis and organic carbon assimilation. Under such conditions, cells exhibit a reduced capacity for photosynthesis but a higher growth rate, compared to phototrophic cultures. Better understanding of the down regulation of photosynthesis would enable more efficient conversion of carbon into valuable products like biofuels. In this study, Flux Balance Analysis (FBA) and Flux Variability Analysis (FVA) have been used with a genome scale model of C. reinhardtii to examine changes in intracellular flux distribution in order to explain their changing physiology. Additionally, a reaction essentiality analysis was performed to identify which reaction subsets are essential for a given growth condition. Our results suggest that exogenous acetate feeds into a modified tricarboxylic acid (TCA) cycle, which bypasses the CO2 evolution steps, explaining increases in biomass, consistent with experimental data. In addition, reactions of the oxidative pentose phosphate and glycolysis pathways, inactive under phototrophic conditions, show substantial flux under mixotrophic conditions. Importantly, acetate addition leads to an increased flux through cyclic electron flow (CEF), but results in a repression of CO2 fixation via Rubisco, explaining the down regulation of photosynthesis. However, although CEF enhances growth on acetate, it is not essential-impairment of CEF results in alternative metabolic pathways being increased. We have demonstrated how the reactions of photosynthesis interconnect with carbon metabolism on a global scale, and how systems approaches play a viable tool in understanding complex relationships at the scale of the organism.
We present the laser architecture that will be constructed as a pump laser for a Multi-TW OPCPA component test laboratory using glass rod amplifiers and a regenerative amplifier seeded by a modulated fiber laser source.
As global plastic pollution is gaining increased attention, the use of bio-based plastics, especially in the food packaging sector, is growing in popularity. While this move is regarded as a solution to plastic pollution, it may shift or create detrimental impacts elsewhere in the production, consumption, management system, a possibility that is underexplored. The aim of the present study is to identify the potential challenges and trade-offs associated with the introduction of bio-based plastics in the food packaging industry, and highlight issues relevant to policy and decision-making processes. We employ a whole system approach to review the literature and assess holistically the performance of bio-based plastics, which looks at the entire lifecycle of bio-based plastic packaging (i.e. production, consumption, management) and considers wider aspects in the environmental, economic, social and technical sustainability domains. Based on our findings, we developed, and present herein, a sustainability decision matrix, a novel guiding tool, which can provide important insights into the potential impacts of the introduction of larger amount of bio-based plastic food packaging in the future and support decision-making processes. In conclusion, our preliminary high-level assessment of the bio-based plastics production, use and management system clearly reveals a number of blind-spots across the entire system that are currently ignored by the use of single-dimensional approaches. This highlights that the sustainability assessment of specific bio-based polymers requires thorough and further research that takes into account the type of feedstock, infrastructure availability, and interactions between sustainability domains, to ensure that the substitution of petrochemical-based plastics with bio-based alternatives in food packaging sector will not lead to unintended consequences.