Mitochondria are semi-autonomous organelles that supply energy for cellular biochemistry through oxidative phosphorylation. Within a cell, hundreds of mobile mitochondria undergo fusion and fission ...events to form a dynamic network. These morphological and mobility dynamics are essential for maintaining mitochondrial functional homeostasis, and alterations both impact and reflect cellular stress states. Mitochondrial homeostasis is further dependent on production (biogenesis) and the removal of damaged mitochondria by selective autophagy (mitophagy). While mitochondrial function, dynamics, biogenesis and mitophagy are highly-integrated processes, it is not fully understood how systemic control in the cell is established to maintain homeostasis, or respond to bioenergetic demands. Here we used agent-based modeling (ABM) to integrate molecular and imaging knowledge sets, and simulate population dynamics of mitochondria and their response to environmental energy demand. Using high-dimensional parameter searches we integrated experimentally-measured rates of mitochondrial biogenesis and mitophagy, and using sensitivity analysis we identified parameter influences on population homeostasis. By studying the dynamics of cellular subpopulations with distinct mitochondrial masses, our approach uncovered system properties of mitochondrial populations: (1) mitochondrial fusion and fission activities rapidly establish mitochondrial sub-population homeostasis, and total cellular levels of mitochondria alter fusion and fission activities and subpopulation distributions; (2) restricting the directionality of mitochondrial mobility does not alter morphology subpopulation distributions, but increases network transmission dynamics; and (3) maintaining mitochondrial mass homeostasis and responding to bioenergetic stress requires the integration of mitochondrial dynamics with the cellular bioenergetic state. Finally, (4) our model suggests sources of, and stress conditions amplifying, cell-to-cell variability of mitochondrial morphology and energetic stress states. Overall, our modeling approach integrates biochemical and imaging knowledge, and presents a novel open-modeling approach to investigate how spatial and temporal mitochondrial dynamics contribute to functional homeostasis, and how subcellular organelle heterogeneity contributes to the emergence of cell heterogeneity.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In permissioned blockchains, a set of identifiable miners validates transactions and creates new blocks. In scholarship, the proposed solution for the consensus protocol is usually inspired by the ...Byzantine fault tolerance (BFT) based on voting rather than the proof-of-work (PoW). The advantage of PoW with respect to BFT is that it allows the final user to evaluate the cost required to change a confirmed transaction without the need to trust the consortium of miners. In this paper, we analyse the problems that arise from the application of PoW in permissioned blockchains. In standard PoW, it may be easy for colluded miners to temporarily reach 50% of the total hash power (HP). Moreover, since mining rewards are not usually expected in permissioned contexts, the problem of balancing the computational efforts among the miners becomes crucial. We propose a solution based on a sliding window algorithm to address these problems and analyse its effectiveness in terms of fairness and security. Furthermore, we present a quantitative, analytical model in order to assess its capacity to balance the hash power provided by heterogeneous miners. Our study considers the trade-off between the need to trust the entire consortium of miners guaranteed by the global HP invested by the mining process and the need to prevent collusion among malicious miners aimed at reaching 50% of the total HP. As a result, the model can be used to find the optimal parameters for the sliding window protocol.
Trypanosomatids are the etiologic agents of various infectious diseases in humans. They diverged early during eukaryotic evolution and have attracted attention as peculiar models for evolutionary and ...comparative studies. Here, we show a meticulous study comparing the incorporation and detection of the thymidine analogs BrdU and EdU in Leishmania amazonensis, Trypanosoma brucei, and Trypanosoma cruzi to monitor their DNA replication. We used BrdU‐ and EdU‐incorporated parasites with the respective standard detection approaches: indirect immunofluorescence to detect BrdU after standard denaturation (2 M HCl) and “click” chemistry to detect EdU. We found a discrepancy between these two thymidine analogs due to the poor detection of BrdU, which is reflected on the estimative of the duration of the cell cycle phases G1, S, and G2. To solve this discrepancy, we increase the exposure of incorporated BrdU using different concentrations of HCl. Using a new value for HCl concentration, we re‐estimated the phases G1, S, G2 + M, and cytokinesis durations, confirming the values found by this approach using EdU. In conclusion, we suggest that the studies using BrdU with standard detection approach, not only in trypanosomatids but also in others cell types, should be reviewed to ensure an accurate estimation of DNA replication monitoring.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
•The effects of screw-pressing parameters on almond fruits using a pilot screw press were evaluated.•Seed moisture content influenced almond oil recovery and chemical quality.•Rosemary extracts ...resulted an interesting natural alternative on almond oil stabilization.
The objectives of this work were to study the combined effects of seed moisture content and pressing temperature on oil recovery and quality parameters of almond oil (AO) and to evaluate the effectiveness of natural (rosemary extract and ascorbyl palmitate) and synthetic antioxidants (TBHQ) on the oxidative stability of AO analyzing chemical changes during an accelerated thermo-oxidation assay. A factorial arrangement was conducted, in pressing experiments, in order to study the combined effects of seed moisture content (4, 6, 8, 10 and 12% (w/w)) and pressing temperature (20, 40 and 60°C) on oil recovery and quality parameters. Oil recovery increased significantly as moisture content raised. The highest oil recovery (79.3%) was obtained at 8% (w/w) seed moisture content and 40°C pressing temperature. All extraction conditions employed were compatible with an acceptable chemical oil quality.
Although in the accelerated assay of thermo-oxidation, the TBHQ became the most effective antioxidant, considering natural alternatives, rosemary extract and ascorbyl palmitate combination showed additional protective effect on the AO preservation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Summary
The aim of this work was to analyse the influence of defatted almond flour on soya bean‐based gluten‐free pasta. Optimal cooking time of pasta varied between 2.0 and 3.5 min, while cooking ...loss ranged 6.1% and 19.7%. The total protein content of samples varied from 30.4% to 41.0% (dry basis, db) in cooked pasta. The total phenols content of cooked samples varied between 1.66 and 2.99 mg ellagic acid equivalent/g, while the antioxidant activity (DPPH•) ranged between 19.1% and 41.9%. The sensory test showed no significant differences between the formulated pasta samples among brightness (3.20–3.27), surface appearance (1.14–1.20), hardness (2.14–2.36) and elasticity (1.56–1.71). Pasta developed is an innovative product that improves nutritional and functional properties of gluten‐free pasta compared to gluten‐free and traditional wheat flour pasta available on market.
Gluten free fresh pasta based on defatted almond flour.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abstract We present the complete mitochondrial genome of Tzotzilthelphusa villarosalensisVillalobos & Álvarez, 2013, a freshwater crab from Mexico. This is the first mitochondrial genome reported for ...the superfamily Pseudothelphusoidea. We performed a de novo assembly from genome skimming reads. The mitochondrial genome of T. villarosalensis has a length of 17,203 bp and its gene topology is similar to other freshwater and marine families, e.g., the position of the cytochrome oxidase complex subunits and ATA synthetase, even the order of nad3, nad5, nad4, nad4L, nad6, and cytb. By contrast, the order and organization of genes like the 16S, 12S, and nad1 are different depending on the phylogenetic group with which they are compared. The phylogenetic analyses placed T. villarosalensis as a sister group of all freshwater crabs reported until now and as part of the subsection Heterotremata. This complete mitochondrial genome could be a reference for further genomic studies of the family Pseudothelphusidae and other primary freshwater crabs.
Introduction. The production of regional food with local and cultural identity has become an attractive business for small-scale producers because it allows them to market their products highlighting ...local ingredients and traditional processing that reflects the know-how of each region. One example is Pasta filata cheese. Objective. To identify sensory characteristics and level of liking for Costa Rican Pasta filata cheeses (Palmito cheese). Materials and methods. The project was carried out at the facilities of the University of Costa Rica, during 2015. Nineteen samples of Costa Rican Palmito cheese were used, with fourteen of them being produced by artisanal producers and five by industrial producers. The methodology of Generic Quantitative Descriptive Analysis (QDA) was followed, with ten trained judges defining twenty-one attributes. Agglomerative Hierarchical Clustering (AHC) and Principal Component Analysis (PCA) were conducted to relate the samples to their attributes. Acceptance testing was performed with one hundred consumers. Consumer AHC and external preference mapping were applied to correlate the results of the liking with those of the QDA. Results. Significant differences (p<0,05) among samples were obtained in the QDA for all attributes. The samples were grouped into three clusters based on similarity attributes. The PCA showed one group, primarily consisting of traditional cheeses, clustered by attributes such as acid and salty flavor, firmness, moisture, and stringy appearance. Another group, corresponding to refrigerated, pasteurized, and unpasteurized cheeses, had a higher intensity of yellow color, greasy texture, softness, and less stringy appearance. A final group, composed of one sample, had a lettuce flavor. Conclusion. Through the external preference mapping, it was concluded that consumers like the majority of industrial Palmito cheeses, but they prefer traditional ones with characteristics such as stringy and creamy flavor.
Objetivo: Describir cómo viven y afrontan los profesionales de enfermería la experiencia de cuidar personas con cáncer. Materiales y métodos: cualitativo fenomenológico. El tamaño de la muestra se ...definió por la saturación teórica, conformada por seis profesionales de enfermería que laboraban en oncología. El instrumento fue la entrevista a profundidad. Se mantuvo la reflexibilidad, también la credibilidad a través de una segunda entrevista para corroborar los datos interpretados, notas de campo y relectura con investigadores asesores. Para el análisis de la información se utilizó el método de Taylor y Bogdan, se plasmaron en matrices de análisis y gráficos. Fue avalado por el Comité de Ética y se utilizó el consentimiento informado. Resultados: se develaron dos temas centrales, el primero fue titulado “Que tengo que vivir, que tengo que hacer, con quien debo compartir” mecanismos de afrontamiento desde el interior y el segundo “Hay otras formas para descargarnos” mecanismos de afrontamiento desde afuera. Adicionalmente se generaron los siguientes subtemas: transformar el concepto de muerte, tener características especiales, cambiar la forma de ver la vida, ser espiritual, la seguridad que ofrece el conocimiento científico, la seguridad que ofrece la experiencia laboral, el apoyo institucional para el bienestar del trabajador y la formación universitaria en el cuidado oncológico. Conclusiones: la experiencia de cuidar a pacientes con cáncer develó mecanismos de afrontamiento que le permiten al enfermero adaptarse y resolver diversas situaciones en su quehacer profesional en los servicios de oncología
Hydrogen fuel cells are promising for reducing emissions from shipping. However, their adoption is limited by high costs, lack of regulations, and lack of infrastructure. The objective of this study ...is to identify the policy instruments needed to accelerate their uptake for the shipping industries of Denmark, Norway, and Sweden. The research is based on a literature review and a stakeholder workshop which served as the basis for proposing three policy packages with different degrees of ambition (low, medium, high). These were evaluated with the TIMES-NEU model, an economic model generator for energy systems, which indicated that the proposed taxes on CO2 emissions and on fossil fuels can help drive the transition away from fossil fuels, but the complete transition requires a ban. The findings show that the proposed policy packages are sufficient to shift the fuel consumption towards methanol for the period of 2025–2040, and towards ammonia for the period of 2040–2050.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Mitochondrial toxicity is a significant concern in the drug discovery process, as compounds that disrupt the function of these organelles can lead to serious side effects, including liver injury and ...cardiotoxicity. Different in vitro assays exist to detect mitochondrial toxicity at varying mechanistic levels: disruption of the respiratory chain, disruption of the membrane potential, or general mitochondrial dysfunction. In parallel, whole cell imaging assays like Cell Painting provide a phenotypic overview of the cellular system upon treatment and enable the assessment of mitochondrial health from cell profiling features. In this study, we aim to establish machine learning models for the prediction of mitochondrial toxicity, making the best use of the available data. For this purpose, we first derived highly curated datasets of mitochondrial toxicity, including subsets for different mechanisms of action. Due to the limited amount of labeled data often associated with toxicological endpoints, we investigated the potential of using morphological features from a large Cell Painting screen to label additional compounds and enrich our dataset. Our results suggest that models incorporating morphological profiles perform better in predicting mitochondrial toxicity than those trained on chemical structures alone (up to +0.08 and +0.09 mean MCC in random and cluster cross-validation, respectively). Toxicity labels derived from Cell Painting images improved the predictions on an external test set up to +0.08 MCC. However, we also found that further research is needed to improve the reliability of Cell Painting image labeling. Overall, our study provides insights into the importance of considering different mechanisms of action when predicting a complex endpoint like mitochondrial disruption as well as into the challenges and opportunities of using Cell Painting data for toxicity prediction.
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IJS, KILJ, NUK, PNG, UL, UM
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