540 research outputs found
Arduino controlled valvometry equipment for laboratory monitoring
High-Frequency Non-Invasive (HFNI) instruments are currently used in bivalve mollusks in order to use them as bioindicators of the local conditions of the environment. Under the STRAUSS project an Arduino controlled equipment has been developed to log the valve movements activity of clams (Polititapes rhomboides) using Hall-efect sensors. The equipment is able to record at 10Hz the signals of 16 Hall-sensors, to store the records in internal microSD cards and to send the stream of data to a personal computer for storing and plotting them in real-time.Peer Reviewe
Arduino controlled valvometry equipment for mussel raft monitoring
High-Frequency Non-Invasive (HFNI) instruments are currently used in bivalve mollusks in order to use them as bio-indicators of the local conditions of the environment. Under the STRAUSS project an Arduino controlled equipment has been developed to log the valve movements activity of mussels (Mytilus galloprovincialis) using Hall-effect sensors. The equipment is able to record at 10Hz the signals of 27 Hall-sensors, temperature, fluorescence and , to store the records in internal microSD cards and to send the stream of data to in premisses data servers for storing and plotting them.Peer Reviewe
Dependences of the Casimir-Polder interaction between an atom and a cavity wall on atomic and material properties
The Casimir-Polder and van der Waals interactions between an atom and a flat
cavity wall are investigated under the influence of real conditions including
the dynamic polarizability of the atom, actual conductivity of the wall
material and nonzero temperature of the wall. The cases of different atoms near
metal and dielectric walls are considered. It is shown that to obtain accurate
results for the atom-wall interaction at short separations, one should use the
complete tabulated optical data for the complex refractive index of the wall
material and the accurate dynamic polarizability of an atom. At relatively
large separations in the case of a metal wall, one may use the plasma model
dielectric function to describe the dielectric properties of wall material. The
obtained results are important for the theoretical interpretation of
experiments on quantum reflection and Bose-Einstein condensation.Comment: 5 pages, 1 figure, iopart.cls is used, to appear in J. Phys. A
(special issue: Proceedings of QFEXT05, Barcelona, Sept. 5-9, 2005
Presentación: A educación social como relato histórico de amplas avenidas pedagóxicas e sociais
As primeiras referencias documentadas sobre a Educación Social sitúanse cronoloxicamente nos inicios do século XIX. Dende entón, en converxencia coa crecente relevancia que irán adquirindo as Ciencias Sociais e a súa énfase na consideración da educación como un feito ou unha práctica social, suscitará novas lecturas do quefacer educativo; en particular os que aspiran a dar resposta ás múltiples necesidades que emerxen da vida cotiá, como son a atención á infancia e á mocidade en situación de inadaptación e risco social, a educación das persoas adultas, ou a animación sociocultural. En todo caso, sen que poidan obviarse os importantes avances que se rexistran nas Ciencias da Educación (en particular da Pedagoxía Social), na acción-Intervención social e o Traballo Social. A democratización das sociedades, o auxe das políticas educativas, sociais e culturais, en conxunción co desenvolvemento da formación académica nas Universidades, xunto coa incesante profesionalización destes ámbitos, marcará decisivamente o seu percorrido histórico en Europa e no mundo. Así se reflicte neste monográfico ao salientar o importante recoñecemento que están adquirindo a Pedagoxía Social e a Educación Social no espazo iberoamericano, con alusións explícitas ás realidades galega, española, portuguesa e latinoamericana, focalizando a mirada histórica en catro dimensións principais: a contextual, a teórico-epistemolóxica, a formativa-académica e a profesional.info:eu-repo/semantics/publishedVersio
Crisis miasténica generalizada en un Shih Tzu
La miastenia gravis (MG) es una de las enfermedades neuromusculares más frecuentes en perros. Según su causa puede ser congénita o adquirida, y según su localización puede ser focal o generalizada. Puede afectar a animales de distintas edades, sexos y razas, aunque existen algunas razas con mayor predisposición. Dentro de los tipos de presentación clínica de las MG adquiridas, está la denominada Miastenia fulminante o Crisis miasténica, cuya frecuencia de aparición es menor, pero de mayor gravedad al poder afectar a los músculos intercostales y al diafragma, comprometiendo seriamente la capacidad respiratoria del animal. El diagnóstico precoz para establecer el tratamiento adecuado es primordial para intentar estabilizar al animal y tratar de recuperar su función motora. En este artículo presentamos un caso de crisis miasténica en un Shih Tzu macho joven, sin enfermedades tumorales o paraneoplásicas reconocidas, y cuyo origen desencadenante de la respuesta inmunomediada no fue posible dilucidar. Un diagnóstico presuntivo precoz mediante pruebas de electrodiagnóstico y su confirmación posterior tras la detección de anticuerpos circulantes contra los receptores de acetilcolina mediante radioinmunoanálisis, permitieron una mejoría más rápida al establecer un diagnóstico temprano y la instauración urgente de una terapia adecuad
Alveolar dimensional changes relevant to implant placement after minimally traumatic tooth extraction with primary closure
The purpose of this study is to evaluate the dimensional changes that occur in the alveolar ridge after minimally traumatic tooth extraction by means of computed tomography (CT), with special focus on the portion of bone supporting the gingival zenith. Twenty subjects with indication for singlerooted tooth extraction and preserved alveolar walls were selected for this study. After a minimally traumatic extraction, two CT scans were performed; the first within 24 hours postextraction (TC1) and the second 6 months (TC2) later. A radiographic guide with a radiopaque marker was used to obtain references that enabled accurate measurements over time, in both vertical and horizontal directions. The bone crest immediately apical to the gingival zenith was identified and termed "osseous zenith". The displacement of the osseous zenith in horizontal and vertical direction was analyzed and correlated with several alveolar anatomical variables with the aim of identifying possible predictors for bone remodeling. Dimensional changes that occur in postextraction sockets within a 6month period showed significant vertical and horizontal displacement of the osseous zenith (p<0.001). Mean vertical resorption was 2.1 ± 1.7 mm, with a median of 1.9 mm and a range of 0.2 to 7.5 mm. Mean horizontal resorption was 1.8 ± 0.8 mm with a median of 1.7 mm and a range of 0.6 to 4.4 mm. However, no correlation was found between the width of the facial alveolar crest and the displacement of the osseous zenith. The results of the present study showed that if the width of the facial crest at the apicalcoronal midpoint is less than 0.7 mm, a high degree of displacement of the osseous zenith (> 3 mm) should be expected. The present study suggests that the width of the alveolar crest at its midlevel, rather than crestal width, may be correlated with the displacement of the osseous zenith.El objetivo del presente estudio es evaluar los cambios dimen sio nales que ocurren en el reborde alveolar luego de realizar una exodoncia atraumática mediante tomografía computada, con especial atención en el tejido óseo que soporta el cénit gingival. Se seleccionaron 20 sujetos con indicación de exodoncia de piezas unirradiculares y que presentaban las paredes alveolares conservadas. Luego de llevar a cabo una exodoncia atraumática se realizaron dos tomografías computadas (TC); la primera dentro de las 24 hs postexodoncia (TC1) y la segunda a los 6 meses (TC2). Se utilizó una guía radiológica con un marcador radiopaco para obtener medidas precisas en el tiempo, tanto en el plano horizontal como vertical. Se identificó la cresta ósea inmediatamente apical al cénit gingival y se definió como “cénit óseo”. Se realizó un análisis del desplazamiento del cénit óseo en el plano horizontal y vertical y se correlacionó con diferentes variables anatómicas con el objetivo de determinar posibles predictores del remo delado óseo. Los cambios dimensionales que ocurren 6 meses postexodoncia mostraron un desplazamiento significativo del cénit óseo (p<0.001) . La reabsorción vertical promedio fue de 2.1 ± 1.7 mm con una media de 1.9 mm y un rango de 0.2 a 7.5 mm. El promedio de reabsorción horizontal fue de 1.8 ± 0.8 mm con una media de 1.7 mm y un rango de 0.6 a 4.4 mm. No se halló correlación entre el ancho de la cresta vestibular y el desplazamiento del cénit óseo. Los resultados del presente estudio mostraron que si el ancho de la cresta vestibular en el punto medio (en sentido apicocoronal) es menor a 0.7mm se puede esperar un desplazamiento del cénit óseo (>3mm). Este estudio sugiere que el ancho de la cresta alveolar en su punto medio podría predecir el desplazamiento del cénit óseo
A theory of Plasma Membrane Calcium Pump stimulation and activity
The ATP-driven Plasma Membrane Calcium pump or Ca(2+)-ATPase (PMCA) is
characterized by a high affinity to calcium and a low transport rate compared
to other transmembrane calcium transport proteins. It plays a crucial role for
calcium extrusion from cells. Calmodulin is an intracellular calcium buffering
protein which is capable in its Ca(2+) liganded form of stimulating the PMCA by
increasing both the affinity to calcium and the maximum calcium transport rate.
We introduce a new model of this stimulation process and derive analytical
expressions for experimental observables in order to determine the model
parameters on the basis of specific experiments. We furthermore develop a model
for the pumping activity. The pumping description resolves the seeming
contradiction of the Ca(2+):ATP stoichiometry of 1:1 during a translocation
step and the observation that the pump binds two calcium ions at the
intracellular site. The combination of the calcium pumping and the stimulation
model correctly describes PMCA function. We find that the processes of
calmodulin-calcium complex attachment to the pump and of stimulation have to be
separated. Other PMCA properties are discussed in the framework of the model.
The presented model can serve as a tool for calcium dynamics simulations and
provides the possibility to characterize different pump isoforms by different
type-specific parameter sets.Comment: 24 pages, 6 figure
Dependences of the van der Waals atom-wall interaction on atomic and material properties
The 1%-accurate calculations of the van der Waals interaction between an atom
and a cavity wall are performed in the separation region from 3 nm to 150 nm.
The cases of metastable He and Na atoms near the metal,
semiconductor or dielectric walls are considered. Different approximations to
the description of wall material and atomic dynamic polarizability are
carefully compared. The smooth transition to the Casimir-Polder interaction is
verified. It is shown that to obtain accurate results for the atom-wall van der
Waals interaction at shortest separations with an error less than 1% one should
use the complete optical tabulated data for the complex refraction index of the
wall material and the accurate dynamic polarizability of an atom. The obtained
results may be useful for the theoretical interpretation of recent experiments
on quantum reflection and Bose-Einstein condensation of ultracold atoms on or
near surfaces of different nature.Comment: 14 pages, 5 figures, 3 tables, accepted for publication in Phys. Rev.
Composição, abundância e biomasa sazonal da assembleia de peixes no subestuário do Solís Chico (Estuário do Río de la Plata, Uruguay)
The large estuaries can present long narrow branches called subestuaries or tidal creeks. These types of subsystems are distributed along the Uruguayan coast of the Río de la Plata estuary and are very important as nursery and refuge areas for fish. For the first time, the seasonal composition and abundance of the fish community of the Solís Chico subestuary was studied by using beach and gill nets. Fourteen species, mainly euryhaline (86%) presented a significant representation of juvenile stages. The fish community was dominated by Odontesthes argentinensis, Platanichthys platana, Mugil liza, Brevoortia aurea, Micropogonias furnieri and Paralichthys orbignyanus, similar to adjacent subestuaries. While Micropogonias furnieri and B. aurea were the most abundant species, some other species were rarely caught. A seasonal variation of the fish assemblage abundance was detected, with higher values in autumn showing a positive correlation with temperature. Species that complete their life cycle in the Río de la Plata estuary, some of which are relevant to fisheries (64% of the analyzed species) were captured in the Solís Chico subestuary. The importance of this environment as a transitional system for some estuarine fish species is advised
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