385 research outputs found
Fast reconstruction of 3D blood flows from Doppler ultrasound images and reduced models
This paper deals with the problem of building fast and reliable 3D
reconstruction methods for blood flows for which partial information is given
by Doppler ultrasound measurements. This task is of interest in medicine since
it could enrich the available information used in the diagnosis of certain
diseases which is currently based essentially on the measurements coming from
ultrasound devices. The fast reconstruction of the full flow can be performed
with state estimation methods that have been introduced in recent years and
that involve reduced order models. One simple and efficient strategy is the
so-called Parametrized Background Data-Weak approach (PBDW). It is a linear
mapping that consists in a least squares fit between the measurement data and a
linear reduced model to which a certain correction term is added. However, in
the original approach, the reduced model is built a priori and independently of
the reconstruction task (typically with a proper orthogonal decomposition or a
greedy algorithm). In this paper, we investigate the construction of other
reduced spaces which are built to be better adapted to the reconstruction task
and which result in mappings that are sometimes nonlinear. We compare the
performance of the different algorithms on numerical experiments involving
synthetic Doppler measurements. The results illustrate the superiority of the
proposed alternatives to the classical linear PBDW approach
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Implementation of an extrachromosomal system for the detection of novel DNA double strand break repair genes in S. cerevisiae
The outcome of DNA damage is diverse and generally adverse. Acute effects arise from disturbed DNA metabolism, triggering cell-cycle arrest or cell death. Long-term effects result from irreversible mutation contributing to oncogenesis and genome instability. In view of the many types of lesions, several pathways were developed to repair these lesions: nucleotide-excision repair (NER), base-excision repair (BER), mismatch repair (MMR), homologous recombination (HR) and non-homologous end joining (NHEJ). The double-strand break (DSB) is the most dangerous type of DNA lesion, it can be repaired mainly by HR (by crossover (CO), gene conversion (GC), and singlestrand annealing (SSA)) or by non-homologous end-joining (NHEJ). When, after replication a second identical DNA copy is available, HR seems to be preferred, other wise cells rely on NHEJ, which is more error prone. Up to now, all DSB repair processes have been studied separately, although it is clear that all of them can occur simultaneously in different proportions. We have created a new molecular plasmid system to simultaneously detect all four types of recombinational DBS repair. To this end, we constructed an in vivo/in vitro HNS plasmid system (HNS: HR, NHEJ, SSA), based upon two topologically different DNA molecules, which allows us to follow all four recombination processes at once. The plasmids, named pURRA8A and pRURA8A, contain two truncated non-functional URA3 genes in direct or inverted orientation respectively, sharing a central homologous region where a l-Scel site was introduced artificially. The plasmids also carry a centromere sequence and two phenotypic markers TRP1 and ADE8. DSB can be induced in vitro at the homologous (l-SceI) or non-homologous (BamHI) region. Yeast transformation with linearized plasmids was performed in strain YPH 250 and isogenic knockout strains lacking either the RAD52 gene involved in HR and SSA, HDF1 (yKU70) and NEJ1 involved in NHEJ. In addition MRE11 complex and MSH2 null mutants were studied. Distribution of DSB repair events among the various pathways was monitored by phenotypic and PCR analysis. The rad52 knockout mutant showed lower levels of CO and SSA, while the hdf1 mutant showed a decrease in conservative and non conservative NHEJ, as expected. These results confirm the validity of the HNS system for monitoring all 4 repair pathways simultaneously. The HNS system has been used to identify new genes involved in DNA damage response. DBS were induced in vivo by the expression of the l-Sce I endonuclease under Gal1-promoter control. After transformation, we performed transposon mutagenesis using the mTn-lacZ/LEU2 library system and selected cells that lost the ability to recombine. From the initial 7000 mutants tested, we selected initially 150 that were rescreening to obtain finally 33 mutants. The identification of the locus of the transposon insertion of all of them was performed. Some known genes (RAD50, SWR1, MCK1, SIN4, RSC2, SWE1 and DBP1) as well as unknown ones (YLR238W, YLR089C, YMR278W) were selected. Null mutants of all them were constructed, DSBR events profile as well as MMS sensitivity were determined. Relative rates of DSB repaired by HR, NHEJ and SSA were examined in all the selected null mutants strains. By comparing the distribution of DSBR by different mechanisms, we were able to obtain a strain-specific profile in which the relative proportions of repair events occurring in the cell were characteristic of that mutation. RSC2 (RSC complex component) and YLR235w (FHA containing protein) genes were selected to further characterisation. Epistatic null mutants analysis with key recombination genes (yku70 and rad52) was performed. MMS sensitivity and survival was analysed, as well as DSB induction in-vivo. This enables us to verify the involvement of a particular gene product in DNA damage response. In particular, we showed that Ylr238w is involved in DNA damage transcription regulation
USA -Chile: Otterbein University, Universidad San Sebastian, November 27-December 22, 2005
Information is provided about the country of Chile in South America for a study-travel class (Spanish 390) that went from Otterbein College in Westerville, Ohio to visit the Universidad San Sebastian in Valdivia, Chile from November 27-December 22, 2005.https://digitalcommons.otterbein.edu/fac_bk/1002/thumbnail.jp
Los éxitos económicos de Bolivia comparados con México y Chile
En este trabajo, buscase avaliar los éxitos económicos del Estado Plurinacional de Bolívia a partir de una compración con México y Chile, países que siguen el modelo neoliberal. El análisis centrase sobre los siguientes aspectos económicos: crecimiento económico, inversión productiva, deuda externa, reservas internacionales, e inflación
Effectiveness if traditional games compared with technological games in classroom climate and student's performance in the EFL classroom : a quasi-experimental research
Tesis (Pedagogía en Inglés)The present study intended to corroborate the hypothesis that both technological and traditional games can help school students in their learning process and that traditional games unlike technological ones, also help in the creation of a better classroom climate. Through a quasi-experiment in three different educational settings, control groups and experimental ones were going to be measured both in students’ performance expressed in marks and in classroom climate measured with a sociometric test. Chile’s current national contingency has prevented this study to be concluded as expected. As an alternative outcome, the researchers carried out a perception study that compared student’s acceptance of both technological and traditional games. The result of this study shows that current students, who are digital natives, showed a slight preference for traditional games over the technological ones, defying the common belief that students only react positively to technology.El presente estudio pretende corroborar la hipótesis de que tanto los juegos tecnológicos como los tradicionales pueden ayudar a los alumnos en su proceso de aprendizaje y que los juegos tradicionales a diferencia de los tecnológicos pueden ayudar, además en la creación de un mejor clima de aula. A través de un cuasi-experimento en tres diferentes establecimientos educacionales, en los grupo de control y experimentales se iba a medir tanto el rendimiento de los estudiantes expresado a través de sus calificaciones, como el clima de aula medido a través de un cuestionario sociométrico. La actual contingencia nacional de Chile ha impedido que este estudio concluya según lo previsto. Como alternativa, los investigadores llevaron a cabo un estudio de percepción que comparó la aceptación de los estudiantes hacia los juegos tecnológicos y tradicionales. El resultado de este estudio muestra que los estudiantes, siendo nativos digitales. mostraron una ligera preferencia por los juegos tradicionales por sobre los tecnológicos, desafiando la creencia general de que los estudiantes solo reaccionan positivamente ante la tecnología
State Estimation with Model Reduction and Shape Variability. Application to biomedical problems
We develop a mathematical and numerical framework to solve state estimation
problems for applications that present variations in the shape of the spatial
domain. This situation arises typically in a biomedical context where inverse
problems are posed on certain organs or portions of the body which inevitably
involve morphological variations. If one wants to provide fast reconstruction
methods, the algorithms must take into account the geometric variability. We
develop and analyze a method which allows to take this variability into account
without needing any a priori knowledge on a parametrization of the geometrical
variations. For this, we rely on morphometric techniques involving
Multidimensional Scaling, and couple them with reconstruction algorithms that
make use of reduced model spaces pre-computed on a database of geometries. We
prove the potential of the method on a synthetic test problem inspired from the
reconstruction of blood flows and quantities of medical interest with Doppler
ultrasound imaging
Control de resistencia bacteriana a los antimicrobianos en pequeños animales en Chile: Esfuerzos integrados bajo el concepto «Una Salud»
Actualmente, la medicina veterinaria se enfrenta a un escenario cada vez más preocupante, generado por la aparición y diseminación de bacterias resistentes a los antimicrobianos que amenazan la salud humana y animal a nivel mundial. Si bien la Organización Mundial de Sanidad Animal (OIE) promueve el uso responsable y prudente de los antimicrobianos, con el fin de prevenir y reducir la selección, emergencia y propagación de bacterias resistentes en los animales y en el ser humano, sus principales líneas de acción en el control y uso prudente de los antimicrobianos han sido focalizadas en los animales de producción.Trabajo publicado en Cagliada, Maria del Pilar Lilia y Galosi, Cecilia Mónica (comps.). I Congreso de Microbiología Veterinaria. Libro de resúmenes. La Plata: Facultad de Ciencias Veterinarias, 2021.Facultad de Ciencias Veterinaria
Centro cívico cultural: integración de la arquitectura patrimonial y contemporánea a través de la cultura
Artículo de gradoEl centro histórico de Bogotá está compuesto por las localidades de Santa Fe, La Candelaria y Los Mártires; el Bronx, hace parte de la localidad de los Mártires. Este barrio ha tenido diferentes cambios por una serie de escenarios urbanísticos e históricos que lo han definido y determinado como es actualmente. Se plantea una renovación urbana y un centro cultural que potencialicen el sector, a partir de una interacción entre patrimonio, arquitectura contemporánea y sus ciudadanos.Introducción
Antecedentes
Metodología
1. Analítico
2. Proyectual
3. Propositivo
Resultados
Composición
Sistema de Permanencias
Estructura
Discusión
Conclusiones
Referencias
AnexosPregradoArquitect
Dialogy as an act of architectural interpretation
Este trabajo aborda la definición de dialogía como una forma de entender la relación entre el arquitecto y el lugar, a través de las variables que se ponen en juego al momento de proyectar. El propósito de la discusión es valorar la forma en la que el arquitecto, como autor de un proyecto arquitectónico, se dispone ante esas variables para descubrirlas y articularlas. En esa relación, la originalidad surge en la apertura del acto de proyectar a las variables históricas, físicas y sociales del contexto, pero, además, a las memorias, experiencias y percepciones del propio arquitecto. Se trata así de un sujeto-autor que se involucra y participa activamente en el reconocimiento del lugar del proyecto y todo lo que él contiene. La dialogía, por lo tanto, corresponde a una actitud en la que el arquitecto comprende el contexto a partir de ponerse en el lugar de un “otro” y, simultáneamente, reinterpreta desde su propia presencia y experiencias lo que contempla.Palabras clave: dialogía, experiencia y arquitectura, memoria.Este trabajo aborda la definición de dialogía como una forma de entender la relación entre el arquitecto y el lugar, a través de las variables que se ponen en juego al momento de proyectar. El propósito de la discusión es valorar la forma en la que el arquitecto, como autor de un proyecto arquitectónico, se dispone ante esas variables para descubrirlas y articularlas. En esa relación, la originalidad surge en la apertura del acto de proyectar a las variables históricas, físicas y sociales del contexto, pero, además, a las memorias, experiencias y percepciones del propio arquitecto. Se trata así de un sujeto-autor que se involucra y participa activamente en el reconocimiento del lugar del proyecto y todo lo que él contiene. La dialogía, por lo tanto, corresponde a una actitud en la que el arquitecto comprende el contexto a partir de ponerse en el lugar de un “otro” y, simultáneamente, reinterpreta desde su propia presencia y experiencias lo que contempla.Palabras clave: dialogía, experiencia y arquitectura, memoria.This paper addresses the definition of dialogy as a way of understanding the relationship between the architect and the place, through the variables that come into play in the process of design. The purpose of the discussion is to evaluate the attitude that the architect, as the author of an architectural project, takes to discover and articulate those variables. In this relationship, originality comes from opening the designing act to historical, physical and social variables of the context, but also to the architect’s memories, experiences and perceptions. The architect is, thus, a subject-author who engages and actively participates in the recognition of the project site and all that it contains. Dialogy, therefore, corresponds to an attitude in which the architect understands the context by putting himself in the place of the “other” and simultaneously interprets, based on his own presence and experience, what he contemplates.Key words: dialogy, experience and architecture, memory
Mercados en disputa: Respuestas organizacionales de las universidades chilenas a la agenda de empleabilidad
This research focuses on the relationship between higher education and the world of work to situate and examine dynamics of change and organizational adaptation of Chilean universities through the development of new management capacities associated with a global employability agenda.To this end, the emergence and spread of employability as a concept, practice and political instrument in higher education worldwide was analysed. The Chilean case was looked into as an iconic example of the economic transformations that the global university sector is currently experimenting. A detailed empiric examination of the main aspects of the discourses on employability in Chile was carried out. The national scenario was described in terms of the insertion and functioning of new management capacities to boost employability at universities. Finally, the origin, development and status of these organisational capacities in relation to the evolution of the formal structure of said organisations was studied in depth.The results allow for the visualisation of significant effects of pressures that comes from universities’ institutional environments. At the same time, it reveals ways in which market disputes become opaque and are ideologically neutralised under the blanket of supposedly shared global aspirations, such as what occurs with the employability agenda. Political Culture and National Identit
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