63 research outputs found

    OC6 Phase Ia: CFD Simulations of the Free-Decay Motion of the DeepCwind Semisubmersible

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    Currently, the design of floating offshore wind systems is primarily based on mid-fidelity models with empirical drag forces. The tuning of the model coefficients requires data from either experiments or high-fidelity simulations. As part of the OC6 (Offshore Code Comparison Collaboration, Continued, with Correlation, and unCertainty (OC6) is a project under the International Energy Agency Wind Task 30 framework) project, the present investigation explores the latter option. A verification and validation study of computational fluid dynamics (CFD) models of the DeepCwind semisubmersible undergoing free-decay motion is performed. Several institutions provided CFD results for validation against the OC6 experimental campaign. The objective is to evaluate whether the CFD setups of the participants can provide valid estimates of the hydrodynamic damping coefficients needed by mid-fidelity models. The linear and quadratic damping coefficients and the equivalent damping ratio are chosen as metrics for validation. Large numerical uncertainties are estimated for the linear and quadratic damping coefficients; however, the equivalent damping ratios are more consistently predicted with lower uncertainty. Some difference is observed between the experimental and CFD surge-decay motion, which is caused by mechanical damping not considered in the simulations that likely originated from the mooring setup, including a Coulomb-friction-type force. Overall, the simulations and the experiment show reasonable agreement, thus demonstrating the feasibility of using CFD simulations to tune mid-fidelity models.</jats:p

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    The productive landscape in the desert margin for the sustainable development of rural settlements: An innovative greenbelt for Maranjab Desert in Iran

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    About two billion rural individuals depend on agricultural systems associated with a high amount of risk and low levels of yield in the drylands of Asia, Africa, and Latin America. Human activities, climate change and natural extreme events are the most important drivers of desertification. This phenomenon has occurred in many regions of Iran, particularly in the villages in the periphery of the central desert of Iran, and has made living in the oases so difficult that the number of abandoned villages is increasing every year. Land abandonment and land-use change increase the risk of desertification. This study aims to respond to the research questions: (i) does the planning of green infrastructures on the desert margin affect the distribution and balance of the population?, (ii) how should the green belt be designed to have the greatest impact on counteracting desertification?, and (iii) does the design of productive landscape provide the solution? Through a wide-ranging and comprehensive approach, this study develops different scenarios for designing a new form of green belt in order to sustainably manage the issues of environmental protection, agricultural tradition preservation and desertification counteraction. This study proposes a new-traditional greenbelt including small low-cost and low-tech projects adapted to rural scale

    Coprevalence of Hidradenitis Suppurativa and Psoriasis: Detailed Demographic, Disease Severity and Comorbidity Pattern

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    Background and Objectives: Hidradenitis suppurativa (HS) and plaque psoriasis (Pso) are supposed to have a coprevalence. However, data showing a more detailed description of patients with both diseases are rare. In this study, we characterized patients with both skin diseases in terms of onset, disease course, severity, concomitant diseases and therapeutical management. Patients and Methods: Data from 28 patients with a confirmed codiagnosis of HS and Pso from 2 university hospitals presented between 2015 and 2019 were evaluated retrospectively. For further characterization, patients were divided into different cohorts depending on whether HS or Pso was diagnosed as the first disease. Results: The average age of patients with a coprevalence of both diseases was 44.4 years with a female/male ratio of 1:1.15. Fifteen patients were diagnosed first with HS at an average age of 22.8 years, 13 patients first showed symptoms of Pso at a mean age of 21.7 years. The average time to the onset of the corresponding second disease was 14.3 years. Patients with HS as first disease showed a significantly severer form of HS compared to patients with a first diagnosis of Pso (mean highest International Hidradenitis Suppurativa Severity Score System: 23.5 vs. 8.2; p = 0.02). Severity of psoriatic disease in patients with HS at first diagnosis was numerically lower but not significant compared to the cohort with Pso at first diagnosis (mean highest Psoriasis Area and Severity Index: 7.8 vs. 13.2; p = 0.299). The most frequent comorbidity in all patients was obesity (64.3%; mean body mass index: 32.2) followed by psychiatric complaints (25%) and psoriatic arthritis (21.4%). Adalimumab was the most commonly used drug that had a positive effect on both diseases, HS and Pso. Conclusions: In patients with a coprevalence of HS and Pso, the disease which occurs first appears to take a severer course, with an increased risk of development of obesity and psychiatric comorbidity in both cohorts
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