747 research outputs found
Análisis predictivo de RNI en sistemas de telecomunicaciones: caso de estudio Gran Mendoza
En la actualidad, debido al permanente y vertiginoso avance de la tecnología, estamos expuestos a radiaciones de campos electromagnéticos producidos por una gran diversidad de fuentes. Esto impacta en la sociedad debido al temor existente, producto de la incertidumbre científica de los posibles efectos negativos que éstas puedan tener en la salud y el ambiente.
Teniendo en cuenta este antecedente, en el presente trabajo se presenta un proyecto que consiste en evaluar los niveles de “Contaminación Electromagnética” dentro de la Ciudad de Mendoza. Con dicho análisis se podrá determinar la situación actual de las Radiaciones No Ionizantes (RNI) en las zonas evaluadas, permitiendo una concienzuda evaluación de la situación y, de esa manera, la posibilidad de establecer tareas de prevención.Eje: Procesamiento de Señales y Sistemas de Tiempo RealRed de Universidades con Carreras en Informática (RedUNCI
Universal relations for rotating Boson Stars
Boson stars represent a hypothetical exotic type of compact stellar object
that may be observed from the gravitational signal of coalescing binaries in
current and future GW detectors. In this work we show that the moment of
inertia , the (dimensionless) angular momentum and the quadrupole
moment of rotating boson stars obey a universal relation, valid for a wide
set of boson star models. Further, the obtained relation clearly
differs from its famous neutron star counterpart, providing us with an
unequivocal diagnostic tool to distinguish boson stars from ordinary compact
stars or other celestial bodies in GW observations. Such universal (i.e.
model-independent) relations also provide a useful tool to probe the strong
gravity regime of general relativity and to constrain the equation of state of
matter inside compact stars.Comment: 7 pages, 4 figures. In this current version, we have corrected a typo
in eq.17 and also changed the table of coefficients, and figures [2],[3], and
[4] where we had a normalization numerical issue that now is fixe
Análisis predictivo de RNI en sistemas de telecomunicaciones: caso de estudio Gran Mendoza
En la actualidad, debido al permanente y vertiginoso avance de la tecnología, estamos expuestos a radiaciones de campos electromagnéticos producidos por una gran diversidad de fuentes. Esto impacta en la sociedad debido al temor existente, producto de la incertidumbre científica de los posibles efectos negativos que éstas puedan tener en la salud y el ambiente.
Teniendo en cuenta este antecedente, en el presente trabajo se presenta un proyecto que consiste en evaluar los niveles de “Contaminación Electromagnética” dentro de la Ciudad de Mendoza. Con dicho análisis se podrá determinar la situación actual de las Radiaciones No Ionizantes (RNI) en las zonas evaluadas, permitiendo una concienzuda evaluación de la situación y, de esa manera, la posibilidad de establecer tareas de prevención.Eje: Procesamiento de Señales y Sistemas de Tiempo RealRed de Universidades con Carreras en Informática (RedUNCI
Construyendo docentes críticos a través del método biográfico-narrativo
The narrative biographical method is the focus of this qualitative research. The objective is to show the validity of this method as a training strategy for future teachers. A strategy that improves the capacity of critical analysis and with that, of reformulation of the budgets of the school culture. The sample is composed of 383 students of the Master's Degree in Secondary Education Teaching of the University of Extremadura (Spain). When applying this method in teacher training programs, there is an alternative to traditional research, training and social action. As a result, three resources are cultivated to train future teachers at the same time; As the students learn the method, they carry out an evaluation process, which is useful for their training and future competence as professionals. Therefore, the students themselves acquire a heuristic and hermeneutical process to evaluate and become researchers of their own professional prospective and experience.El método biográfico narrativo es el foco de esta investigación de corte cualitativo. El objetivo es mostrar la validez de este método como estrategia de formación para futuros docentes.
Una estrategia que mejora la capacidad de análisis crítico y con ello de reformulación de los presupuestos de la cultura escolar. La muestra está compuesta por 383 estudiantes del Máster Universitario de Formación del Profesorado de Educación Secundaria de la Universidad de Extremadura (España). Al aplicar este método en los programas de formación del profesorado aparece una alternativa a la investigación tradicional, a la formación y a la acción social. Como resultados, se cultivan tres recursos para capacitar a futuros docentes al mismo tiempo; a medida que los alumnos aprenden el método, realizan un proceso de evaluación, que resulta útil para su formación y competencia futura como profesionales. Por lo tanto, los propios estudiantes adquieren un proceso heurístico y hermenéutico para evaluar y convertirse en investigadores de su propia experiencia y prospectiva profesional.Universidad Pablo de Olavid
Fumaric Acid Production by R. arrhizus NRRL 1526 Using Apple Pomace Enzymatic Hydrolysates: Kinetic Modelling
Fumaric acid is one of the most promising biorefinery platform chemicals, fruit residues being a very suitable raw material for its production in second generation biorefineries. In particular, apple pomace is a plentiful residue from the apple juice industry, with apple being the second largest fruit crop in the world, with a production that increased from 46 to 86 Mtons in the 1994–2021 period. With a global apple juice production of more than 4.5 Mtons, a similar amount of apple pomace is produced yearly. In this work, apple pomace hydrolysate has been obtained by enzymatic hydrolysis and further characterized for its content in sugars, phenolics and nitrogen using different analytic methods, based on HPLC and colorimetric techniques. Previous to the use of this hydrolysate (APH), we studied if the addition of fructose to the usual glucose-rich broth could lead to high fumaric acid yields, titers and productivities. Afterwards, APH fermentation was performed and improved using different nitrogen initial amounts, obtaining production yields (0.32 gFumaric acid/gconsumed sugar) similar to those obtained with synthetic media (0.38 gFumaric acid/gconsumed sugar). Kinetic modelling was employed to evaluate, explain, and understand the experimental values and trends of relevant components in the fermentation broth as functions of the bioprocess time, proposing a suitable reaction scheme and a non-structured, non-segregated kinetic model based on it
Molecular Nitrides with Titanium and Rare-Earth Metals
A series of titanium-group 3/lanthanide metal complexes have been prepared by reaction of [{Ti(eta(5)-C5Me5)(mu-NH)}(3)(mu(3)-N)] (1) with halide, triflate, or amido derivatives of the rare-earth metals. Treatment of 1 with metal halide complexes [MCl3(thf)(n)] or metal trifluoromethanesulfonate derivatives [M(O3SCF3)(3)] at room temperature affords the cube-type adducts [X3M{(mu(3)-NH)(3)Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)}] (X = Cl, M = Sc (2), Y (3), La (4), Sm (5), Er (6), Lu (7); X = OTf, M = Y (8), Sm (9), Er (10)). Treatment of yttrium (3) and lanthanum (4) halide complexes with 3 equiv of lithium 2,6-dimethylphenoxido [LiOAr] produces the aryloxido complexes [(ArO)(3)M{(mu(3)-NH)(3)Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)}] (M = Y (11), La (12)). Complex 1 reacts with 0.5 equiv of rare-earth bis(trimethylsilyl)amido derivatives [M{N(SiMe3)(2)}(3)] in toluene at 85-180 degrees C to afford the corner-shared double-cube nitrido compounds [M(mu(3)-N)(3)(mu(3)-NH)(3){Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)}(2)] (M = Sc (13), Y (14), La (15), Sm (16), Eu (17), Er (18), Lu (19)) via NH(SiMe3)(2) elimination. A single-cube intermediate [{(Me3Si)(2)N}Sc{(mu(3)-N)(2)(mu(3)-NH)Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)}] (20) was obtained by the treatment of 1 with 1 equiv of the scandium bis(trimethylsilyl)amido derivative [Sc{N(SiMe3)(2)}(3)]. The X-ray crystal structures of 2, 7, 11, 14, 15, and 19 have been determined. The thermal decomposition in the solid state of double-cube nitrido complexes 14, 15, and 18 has been investigated by thermogravimetric analysis (TGA) and differential thermal analysis (DTA) measurements, as well as by pyrolysis experiments at 1100 degrees C under different atmospheres (Ar, H-2/N-2, NH3) for the yttrium complex 14.Ministerio de Educación y Ciencia de España, Comunidad de Madrid, Universidad de Alcal
NANOIMPLANT: nanostructured biocompatible coatings to prevent orthopedic implant infections
Comunicación presentada en el ImagineNano, celebrado en Bilbao del 10 al 13 de marzo de 2015.Bacterial colonization and biofilm formation on orthopedic implants is one of the worst possible scenarios in orthopedic surgery, in terms of both patient prognosis and healthcare costs. Tailoring the surface of these orthopedic implants to actively promote bone bonding, while avoiding bacterial colonization, represents an interesting challenge to reach better clinical outcomes. Currently, it has been demonstrated a strong dependence of structural features in the nano-scale with antibacterial effects. Several naturally existing surfaces such as plant leaves and insect wings are capable of maintaining a contaminant-free status despite the innate abundance of contaminants in their surrounding environments. These properties are related to the presence of a periodic topography of hexagonal arrays of nanopillar on their surfaces. By mimicking the nature, and to translate this effect to orthopedic metallic biomaterials, a Ti6Al4V alloy of medical grade has been coated with Ti nanostructures employing the glancing angle deposition technique by magnetron sputtering. The resulting surfaces have a high density of nanocolumnar structures based on Ti, providing high roughness and a notable decrease of wettability. These nanostructured coatings exhibit a selective behavior towards osteoblast and bacteria proliferation. While these nanotextured surfaces strongly impair bacteria adhesion and inhibit biofilm formation, the osteoblasts exhibit almost identical behavior than that obtained onto the initial Ti6Al4V substrates. This selective behavior is discussed on the basis of a “lotus leaf effect” induced by the nanostructured surface and the different size of osteoblasts and bacteria. The obtained results provide new perspectives for manufacturing Ti6Al4V-based implants to prevent infections. Moreover, it is also worth noticing that our work has won the 2014 IDEA² Madrid Award of the Madrid-MIT M+Vision Consortium, a partnership of the regional government of Madrid and the Massachusetts Institute of Technology (MIT), which fosters innovation in biotechnology.Peer Reviewe
Decision-making tools for sustainable planning and conceptual framework for the energy–water–food nexus
Suplemento 6 con el título: Technologies and Materials for Renewable Energy, Environment and Sustainability[EN] The impact assessment of energy strategies, more specifically those that promote an integrated approach on resource
management in other sectors such as water and food, requires knowledge related to the evaluation of the quality and knowledge
that may be estimated by quantitative means. The present paper makes inquiries into those knowledge requirements in addition to
review the means used to obtain it—including the required entries and the results they provide. In response to the recognized
problems in knowledge, this paper introduces a basic reference structure underlying a system to evaluate the way that a
progressive development of inexhaustible energies in a particular geographical region can affect the demand of water and food.
Then, the proposed conceptual framework constitutes a novel approach for energy policy makers which only consider partial
impacts of the energy management. By considering the nexus of energy, water and food, energy management policies may be
redefined and differences with current policies must be investigated.SICabildo de Tenerif
El abordaje transapofisario en las fracturas complejas del extremo distal femoral y proximal tibial
Los autores presentan las ventajas e inconvenientes, así como los distintos
pasos de la técnica quirúrgica en el abordaje transapofisario, para
resolver aquellas fracturas complejas tanto del extremo distal femoral como
del extremo proximal tibial, en donde una amplia exposición del foco
fracturario es imprescindible para lograr la restauración lo más anatómica
posible de la superficie articular, que le permita a los pacientes reiniciar una
movilización articular precoz.
Consideran a este tipo de abordaje quirúrgico como muy beneficioso e imprescindible
en estas fracturas tan complejas, presentando su experiencia
al respecto.The authors show the advantages and disadvantages, as well as
somo differents points of the surgical technique at the transapophyseal
approach, for complex fractures of the distal end of the
femur and proximal tibial plateau, when an extensible exposur e is
essential to obtain an anatomic restitution of the articular surface,
and to allow to the patient to mobilize the joint at once.
They consider this type of surgical approach as very beneficial
and essentia] in these fractures so complex. They present their
experience
New data on the acanthocephalan <i>Neoechinorhynchus villоldoi</i> Vizcaíno, 1992 (Neoechinorhynchidae: Acanthocephala), based on specimens found in <i>Austrolebias bellottii</i> (Steindachner, 1881) (Rivulidae: Cyprinodontiformes) from Punta Indio, Argentina
In a survey of parasites on the killifish, Austrolebias bellottii from Punta Indio and Magdalena, Argentina, the acanthocephalan Neoechinorhynchus villoldoi was found. This parasite had not been recorded since 1992 when it was described for the first time parasitizing Corydoras paleatus (Jenyns, 1842). The type material of N. villoldoi was examined, and with addition of the new specimens, the measurements range was extended. This is the first record of an acanthocephalan in the annual fish, A. bellottii.Facultad de Ciencias Naturales y Muse
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