334 research outputs found
On - Component Models on Cayley Tree: The General Case
In the paper we generalize results of paper [12] for a - component models
on a Cayley tree of order . We generalize them in two directions: (1)
from to any (2) from concrete examples (Potts and SOS models)
of component models to any - component models (with nearest neighbor
interactions). We give a set of periodic ground states for the model. Using the
contour argument which was developed in [12] we show existence of different
Gibbs measures for -component models on Cayley tree of order .Comment: 8 page
Hydrodynamic model for three-phase internal- and external-loop airlift reactors
A mathematical model predicting the hydrodynamic behaviour of three-phase airlift reactors, working with low-density solids and
with high solids loading, was developed. The model allows for the prediction of local gas holdup and liquid velocity in airlift
bioreactors. Model was validated for an external-loop airlift reactor and an internal-loop airlift reactor with an enlarged degassing
zone, being a good agreement obtained between calculated and experimental data.Fundação para a Ciência e a Tecnologia (FCT)
Junta Nacional de Investigação Científica e Tecnológica (JNICT) - PRAXIS 2/2.1/BIO/1061/95
Instituto de Biotecnologia e Química Fina (IBQF) - GGP XXI/BD/2937/9
Characterization of bubbles in a bubble column by image analysis
Fundação para a Ciência e a
Tecnologia (FCT); EC
Modelling design of multiphase bubble-bed reactors for advanced food-industry technologies
Project Copernicu
Hydrodynamics of a three-phase external-loop airlift bioreactor
The effect of the distributing plate orifice diameter, airflow rate, solids loading and solids density on the hydrodynamic
characteristics - gas holdup, circulation time and liquid velocity - of a three-phase external-loop airlift reactor was characterized. It
was observed that the gas distributor has a small effect on riser gas holdup, circulation time and downcomer liquid velocity. On the
contrary, the airflow rate, solids loading and solids density significantly affect the hydrodynamic characteristics of the external-loop
airlift reactor. A previously described model was used to estimate simultaneously both the riser gas holdup and the downcomer linear
liquid velocity. The model simulated with high-accuracy experimental data obtained with three different distributing plate orifice
diameters, two solids density and solids loading up to 30% (v/v).Fundação para a Ciência e a Tecnologia (FCT) – PRAXIS/2/2.1/BIO/1061/95.Comunidade Europeia - INCO-COPERNICUS - Contract Nº ERB IC15-CT-98-0904 e Instituto de Biotecnologia e Química Fina (IBQF) - GGP XXI/BD/2937/96
Modelling design of multiphase bubble-bed reactors for advanced food-industry applications
An EC project (IC15-CT98-0904 / PL979021) under this title commenced November 1998
courtesy of Dr Jindrich Zahradnik, sadly since deceased. In dedication to his memory overviewed
here are contributions from the four partners whose lead investigators appear as authors (plus
coordinator as corresponding author) with principals and researchers recognised in cited
literature. A website (www.copernicus.aston.ac.uk) has been launched to disseminate major
individual components and collaborations facilitated by study exchanges, also envisaged
exploitation by industries. Drawing on this material we outline partners' established expertise and
its unification under EC umbrella funding. To avoid confusion on due credit for contributions,
references are designated by first letters of the above-named authors. At risk of appearing to
favour ones' own wares, we humbly refer readers to our cited papers for contextual
commentaries
A Contour Method on Cayley tree
We consider a finite range lattice models on Cayley tree with two basic
properties: the existence of only a finite number of ground states and with
Peierls type condition. We define notion of a contour for the model on the
Cayley tree. By a contour argument we show the existence of different
(where is the number of ground states) Gibbs measures.Comment: 12 page
Development of a Sandwich ELISA to Measure Exposure to Occupational Cow Hair Allergens
Background: Cow hair and dander are important inducers of occupational allergies in cattle-exposed farmers. To estimate allergen exposure in farming environments, a sensitive enzyme immunoassay was developed to measure cow hair allergens. Methods: A sandwich ELISA was developed using polyclonal rabbit antibodies against a mixture of hair extracts from different cattle breeds. To assess the specificity of the assay, extracts from other mammalian epithelia, mites, molds and grains were tested. To validate the new assay, cow hair allergens were measured in passive airborne dust samples from the stables and homes of farmers. Dust was collected with electrostatic dust fall collectors (EDCs). Results: The sandwich ELISA was found to be very sensitive (detection limit: 0.1 ng/ml) and highly reproducible, demonstrating intra-and interassay coefficients of variation of 4 and 10%, respectively. The assay showed no reactivity with mites, molds and grains, but some cross-reactivity with other mammalian epithelia, with the strongest reaction with goat. Using EDCs for dust sampling, high concentrations of bovine allergens were measured in cow stables (4,760-559,400 mu g/m(2)). In addition, bovine allergens were detected in all areas of cattle farmer dwellings. A large variation was found between individual samples (0.3-900 mu g/m(2)) and significantly higher values were discovered in changing rooms. Conclusion: The ELISA developed for the detection of cow hair proteins is a useful tool for allergen quantification in occupational and home environments. Based on its low detection limit, this test is sensitive enough to detect allergens in passive airborne dust. Copyright (C) 2011 S. Karger AG, Base
In Silico Simulations Reveal That Ryr Distribution Affects the Dynamics of Calcium Release in Cardiac Myocytes
The dyads of cardiac myocytes contain ryanodine receptors (RYRs) that generate calcium sparks upon activation. To test how geometric factors of RYR distribution contribute to the formation of calcium sparks, which cannot be addressed experimentally, we performed in silico simulations on a large set of models of calcium release sites (CRSs). Our models covered the observed range of RYR number, density, and spatial arrangement. The calcium release function of CRSs was modeled by RYR openings, with an open probability dependent on concentrations of free Ca2+ and Mg2+ ions, in a rapidly buffered system, with a constant open RYR calcium current. We found that simulations of spontaneous sparks by repeatedly opening one of the RYRs in a CRS produced three different types of calcium release events (CREs) in any of the models. Transformation of simulated CREs into fluorescence signals yielded calcium sparks with characteristics close to the observed ones. CRE occurrence varied broadly with the spatial distribution of RYRs in the CRS but did not consistently correlate with RYR number, surface density, or calcium current. However, it correlated with RYR coupling strength, defined as the weighted product of RYR vicinity and calcium current, so that CRE characteristics of all models followed the same state-response function. This finding revealed the synergy between structure and function of CRSs in shaping dyad function. Lastly, rearrangements of RYRs simulating hypothetical experiments on splitting and compaction of a dyad revealed an increased propensity to generate spontaneous sparks and an overall increase in calcium release in smaller and more compact dyads, thus underlying the importance and physiological role of RYR arrangement in cardiac myocytes. © 2021 Iaparov et al.The research was supported by Russian Foundation for Basic Research according to research project no. 18-31-00153 (development of the computational model of CRS); by the Government of the Russian Federation (program 02.A03.21.0006); by the Ministry of Science and Higher Education of the Russian Federation (project no. FEUZ-2020-0054); by the Slovak Research and Development Agency (project APVV-15-0302); by SAV-TUBITAK (project JRP/2019/836/RyRinHeart); and by the Operational Program Integrated Infrastructure for the project “Long-term strategic research of prevention, intervention, and mechanisms of obesity and its comorbidities,” ITMS: 313011V344, co-financed by the European Regional Development Fund. The authors declare no competing financial interests
Free Energy Minimizers for a Two--Species Model with Segregation and Liquid-Vapor Transition
We study the coexistence of phases in a two--species model whose free energy
is given by the scaling limit of a system with long range interactions (Kac
potentials) which are attractive between particles of the same species and
repulsive between different species.Comment: 32 pages, 1 fig, plain tex, typeset twic
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