1,443 research outputs found
Thermodynamic scheme of inhomogeneous perfect fluid mixtures
We analyze the compatibility between the geometrodynamics and thermodynamics
of a binary mixture of perfect fluids which describe inhomogeneous cosmological
models. We generalize the thermodynamic scheme of general relativity to include
the chemical potential of the fluid mixture with non-vanishing entropy
production. This formalism is then applied to the case of Szekeres and Stephani
families of cosmological models. The compatibility conditions turn out to
impose symmetry conditions on the cosmological models in such a way that only
the limiting case of the Friedmann-Robertson-Walker model remains compatible.
This result is an additional indication of the incompatibility between
thermodynamics and relativity
The Stokes-Einstein Relation at Moderate Schmidt Number
The Stokes-Einstein relation for the self-diffusion coefficient of a
spherical particle suspended in an incompressible fluid is an asymptotic result
in the limit of large Schmidt number, that is, when momentum diffuses much
faster than the particle. When the Schmidt number is moderate, which happens in
most particle methods for hydrodynamics, deviations from the Stokes-Einstein
prediction are expected. We study these corrections computationally using a
recently-developed minimally-resolved method for coupling particles to an
incompressible fluctuating fluid in both two and three dimensions. We find that
for moderate Schmidt numbers the diffusion coefficient is reduced relative to
the Stokes-Einstein prediction by an amount inversely proportional to the
Schmidt number in both two and three dimensions. We find, however, that the
Einstein formula is obeyed at all Schmidt numbers, consistent with linear
response theory. The numerical data is in good agreement with an approximate
self-consistent theory, which can be used to estimate finite-Schmidt number
corrections in a variety of methods. Our results indicate that the corrections
to the Stokes-Einstein formula come primarily from the fact that the particle
itself diffuses together with the momentum. Our study separates effects coming
from corrections to no-slip hydrodynamics from those of finite separation of
time scales, allowing for a better understanding of widely observed deviations
from the Stokes-Einstein prediction in particle methods such as molecular
dynamics.Comment: Submitte
Perfil InmunohistoquĂmico de los Tipos de Fibras en el MĂşsculo Vocal Humano
Galdames, IS (reprint author), Univ Talca, Escuela Fonoaudiol, Ave Lircay S-N,Oficina 104, Talca, Chile.he vocal muscle is a striated muscle with important functions in the emission of laryngeal sound and physiology of the voice. Therefore the knowledge of its constitution is the basis for the prevention and management of voice disorders. We used 10 samples from the middle third of vocal muscles obtained from autopsies of 6 male and 4 female subjects aged between 36 and 71 years. The samples were analyzed with BA-F8 monoclonal antibody to slow type I fibers, and antimyosin HC monoclonal antibody and antimyosin fast clone MY-32 antibody for types IIA, IIB, IIX, and neonatal fibers. We determined the distribution of the muscle fiber types and morphometric characteristics, evaluating the differences by sex and age group. The human vocal muscle presented a heterogeneous formation with a predominance of type II fibers at 51.99%, while type I fibers reached 48.01%; this difference was significant (p0.05). In conclusion, the human vocal muscle the fibers were predominantly type II fast
Overviews of vaccine technology for neglected diseases in developing Latin America country - Peru
Immunization has been the greatest strategy to prevent sickness and death associated with infectious diseases [1]. So, vaccine technology has evolved to produce more immunogenic vaccines and to avoid the exposure to disease-causing organisms during manufacturing and treatment [2]. Conversely, 2.5 million people are still dying globally each year from vaccine-preventable diseases since the underuse of vaccines and lack vaccines against non-well studied pathogens [2]. Only Cuba, Brazil and Argentina are listed as producers of vaccines against infectious diseases such as yellow fever, leishmaniasis and rotavirus [3]. The roles of mentioned developing countries are crucial because the produced vaccines are economically affordable which increase an increment of vaccine coverage [3]. However, neglected communities are still susceptible to pathogens that are non-well documented since they do not represent a high risk for public health. In Peru, several deaths are associated with the infection of bacteria borne diseases and along to the last decades and preventative treatment is not yet available. It has been developed some research aimed to develop a vaccine against Carrion’s disease in The National Institute of Health from Peru. The employed procedure to produce the vaccine against Carrion’s disease has not described the parameters used for the purification and characterization to obtain a highly pure molecule for animal trial, consequently, the unexpected results could be obtained because the vaccine candidate did not achieve the basic standard for the evaluation [4]. In conclusion, there are few the developing Latin American countries involved in the vaccine technology field, and it is required to integrate effort among global institutions to face diseases that affect neglected communities in developing countries.
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Production of monoclonal antibodies specific to soluble proteins of Bartonella bacilliformis
Bartonella bacilliformis is the causative agent of Carrion’s disease, this illness affects poor communities of Andean valleys (Peru, Colombia and Ecuador) [1]. B. bacilliformis produces a biphasic infection: acute phase presents severe anemia and immunosuppression, and chronic phase involves dermal eruption [1]. Currently, the available tools for the diagnosis of Carrion’s disease include low sensitive serological assays and expensive molecular tools [2]. To improve the diagnosis, this project aims to produce monoclonal antibodies specific soluble proteins of B. bacilliformis. The monoclonal antibodies production was performed immunizing three Balb/C mice with soluble proteins obtained from the total lysate of B. bacilliformis. The immune response was tested by ELISA at a serum dilution of 1:500 and 1:8000, seropositive animals were sacrificed to obtain B lymphocytes from the spleen. The B lymphocytes were fused with Ag8 myeloma cells in HAT medium, the obtained hybridomas were cloned. ELISA evaluation was performed for the selection of the monoclonal-antibody producing clones. The optical densities and antibody titers were analyzed using the statistical package SPSS. 21. The sera titer of immunized mice was equivalent to 0.8-1.0 OD at 1:8000 dilution, whilst the OD of the medium of the hybridomas was 0.2-2.0 (FIG. 1). Clones displaying higher density were growth upon reach OD of 2.0. Monoclonal antibodies were successfully produced, but antibody identification is pending evaluation.
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Pr\ue9cis du Plurilinguisme et du pluriculturalisme
This handbook is organized around linguistic and cultural plurality. The French concept of \uab plurality \ubb has different political connotations than the Angloamerican term \uab diversity \ubb. While \uab diversity \ubb is the ideal of a neo-liberal democracy, \uab plurality \ubb is the ideal of a republican society committed to the tenets of the French
Revolution. Following Bourdieu (1977), it defines language as an \uab instrument of action (or of power) \ubb and aims to reconstruct the complexity of social and linguistic practices that constitute our relationship to the foreign. Plurality here is not defined as the mere coexistence of various languages, but rather as a specific social activity
characterized by the circulation of values across borders, the negotiation of identities, and the inversions\u2013indeed, the inventions\u2013of meaning that are often masked by the shared illusion of successful communication.
Plurality is approached in this book:
- as a complex aggregate, rather than as the simplified object of a communicatively oriented language pedagogy primarily concerned with intelligibility
- as a coherent system of relationships whose description cannot be reduced to a series of mechanical operations
- as a socio-historical construct, observable from many simultaneous, spatiotemporal points of view, such as that of everyday interactions or that of institutions whose symbolic force cannot be accounted for from one point of view alone
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