62 research outputs found
Asymmetric vortex merger: mechanism and criterion
The merging of two unequal co-rotating vortices in a viscous fluid is investigated. Two-dimensional numerical simulations of initially equal sized Lamb-Oseen vortices with differing relative strengths are performed. Results show how the disparity in deformation rates between the vortices alters the interaction. Key physical mechanisms associated with vortex merging are identified. A merging criterion is formulated in terms of the relative timing of core detrainment and destruction. A critical strain parameter is defined to characterize the establishment of core detrainment. This parameter is shown to be directly related to the critical aspect ratio in the case of symmetric merger
Diseño y elaboración de material docente para el seguimiento virtual de Estadística, Muestreo Estadístico e Informática en GAP
La introducción de las tecnologías de la información y la comunicación en los procesos de enseñanza permite un nuevo concepto de alumno-usuario y cambios en el modelo de enseñanza-aprendizaje que nos llevan a una educación superior más flexible. Así, el marco espaciotemporal en el que el alumno desarrolla las actividades de aprendizaje puede ser el hogar, el puesto de trabajo o un centro con recursos para el aprendizaje (como las aulas de informática de libre acceso que pone a disposición del alumno la Universidad de Jaén (UJA)).Destacar que en Gestión y Administración Pública (GAP) se encuentra un elevado número de estudiantes que trabajan para la Administración y que se matriculan con el objetivo de promocionar en su trabajo. Se trata de alumnos que, en general, no pueden asistir diariamente a las clases presenciales y a los que ciertas asignaturas como las de estadística les suponen un gran esfuerzo. Estas situaciones han llevado a la demanda generalizada por parte de los estudiantes universitarios para que se introduzcan cambios en las estrategias didácticas y en los sistemas de comunicación y distribución de los materiales de aprendizaje.El diseño e implantación de campus virtuales ha supuesto un gran reto para la mayor parte de las universidades españolas. En particular, la UJA se encuentra inmersa en este proceso, dando respuestas de diversa índole entre las que se encuentran los programas de innovación docente. Nosotros estamos iniciando a nuestros alumnos en el uso de las TICs, facilitándoles el uso de recursos y las herramientas necesarias para adquirir conocimientos y destrezas en las asignaturas de estadística, muestreo estadístico e informática
Dynamics and Berry phase of two-species Bose-Einstein condensates
In terms of exact solutions of the time-dependent Schrodinger equation for an
effective giant spin modeled from a coupled two-mode Bose-Einstein condensate
(BEC) with adiabatic and cyclic time-varying Raman coupling between two
hyperfine states of the BEC, we obtain analytic time-evolution formulas of the
population imbalance and relative phase between two components with various
initial states, especially the SU(2)coherent state. We find the Berry phase
depending on the number parity of atoms, and particle number dependence of the
collapse revival of population-imbalance oscillation. It is shown that
self-trapping and phase locking can be achieved from initial SU(2) coherent
states with proper parameters.Comment: 18 pages,5 figure
Multidisciplinary exercises: coordination practices and applications from fundamental to applied subjects in agriculture engineering
This activity is carried out in the framework of an innovation project, whose main objective is to coordinate mathematical, physical and engineering contents for a transversal educational path focused on mechatronics, automated control and information and communication technologies. In such sense one important task in this project is the elaboration of practices and joint applications which will be proposed to the students in successive matters upon different points of view: “Common Practices”. Through this activity students will be guided to establish relationships between their scientific basic training and their technological formation. The students will work on the same example during different academic years and semesters using common materials and working spaces. The whole experience will be displayed in Moodle, a virtual learning environment. A preliminary proposal of “Common practice” is presented in this paper as one example: “Design and Analysis of Suspensions Systems for Stabilizing the Roll of Spray Booms”. In this example students of different academic levels are asked to solve the complexity of the problem along different subjects: Field measurements (analysis of variability on chemical applications using a spray boom) will be realized in the Agriculture Machinery topic - equivalent to 4.5 ECTS -. Analytical models for the analysis of different suspension systems in the Mechanics and Mechanisms topic -4.5 ECTS -. In Agriculture Applied Electronics – 2.5 ECTS – sensors and actuators will be studied to design controllers. Control strategies for damping the resonance frequency of the suspension will be studied in Process Simulation and Optimization – 3.5 ECTS –. And, finally, the design and development of a vehicle with a spray bar and the corresponding suspension systems will be done in the Robotics topic – 7 ECTS –
Holonomic quantum gates: A semiconductor-based implementation
We propose an implementation of holonomic (geometrical) quantum gates by
means of semiconductor nanostructures. Our quantum hardware consists of
semiconductor macroatoms driven by sequences of ultrafast laser pulses ({\it
all optical control}). Our logical bits are Coulomb-correlated electron-hole
pairs (excitons) in a four-level scheme selectively addressed by laser pulses
with different polarization. A universal set of single and two-qubit gates is
generated by adiabatic change of the Rabi frequencies of the lasers and by
exploiting the dipole coupling between excitons.Comment: 10 Pages LaTeX, 10 Figures include
Efficacy of Neoadjuvant Carboplatin plus Docetaxel in Triple-Negative Breast Cancer: Combined Analysis of Two Cohorts
Recent studies demonstrate that addition of neoadjuvant (NA) carboplatin (Cb) to anthracycline/taxane chemotherapy improves pathological complete response (pCR) in triple negative breast cancer (TNBC). Effectiveness of anthracycline-free, platinum combinations in TNBC is not well known. Here we report efficacy of NA carboplatin + docetaxel (CbD) in TNBC
Antifungal activity of amphotericin B conjugated to nanosized magnetite in the treatment of paracoccidioidomycosis
This study reports on in vitro and in vivo tests that sought to assess the antifungal activity of a newly developed magnetic carrier system comprising amphotericin B loaded onto the surface of pre-coated (with a double-layer of lauric acid) magnetite nanoparticles. The in vitro tests compared two drugs; i.e., this newly developed form and free amphotericin B. We found that this nanocomplex exhibited antifungal activity without cytotoxicity to human urinary cells and with low cytotoxicity to peritoneal macrophages. We also evaluated the efficacy of the nanocomplex in experimental paracoccidioidomycosis. BALB/c mice were intratracheally infected with Paracoccidioides brasiliensis and treated with the compound for 30 or 60 days beginning the day after infection. The newly developed amphotericin B coupled with magnetic nanoparticles was effective against experimental paracoccidioidomycosis,
and it did not induce clinical, biochemical or histopathological alterations. The
nanocomplex also did not induce genotoxic effects in bone marrow cells. Therefore, it is reasonable to believe that amphotericin B coupled to magnetic nanoparticles and stabilized with bilayer lauric acid is a promising nanotool for the treatment of the experimental paracoccidioidomycosis because it exhibited antifungal activity that was similar to that of free amphotericin B, did not induce adverse effects in therapeutic doses and allowed for a reduction in the number of applications
Use of interactive response devices for the improvement of teaching in the degrees of the Faculty of Sciences
La implantación de los nuevos Grados dentro del EEES supone un nuevo enfoque metodológico, pero sobre todo evaluador. El profesor debe esforzarse en ser capaz de valorar no sólo el nivel de conocimientos del alumnado sobre los contenidos, ya que la sociedad actual demanda un perfil de los egresados más completo basado en la formación por competencias. La adquisición de ambas facetas por parte del alumnado se basa principalmente en actividades presenciales y metodologías docentes aplicadas en el desarrollo de las asignaturas, tanto en grupo reducido como en grupo completo. Por tanto, cualquier herramienta adicional que ayude al docente a facilitar esta doble tarea es bien recibida, pues permitirá evaluar el rendimiento académico global del alumnado. Recientemente la Facultad de Ciencias ha puesto en marcha una experiencia piloto mediante la cual un nutrido grupo de profesores ha incorporado en su docencia un sistema de mandos inalámbricos de respuesta. Actualmente, la Facultad de Ciencias dispone de un total de 82 mandos inalámbricos de respuesta y tres antenas receptoras. Esta nueva tecnología ha permitido al docente realizar, de forma interactiva, preguntas colectivas al alumnado y recoger las respuestas individuales de forma inmediata. Los resultados obtenidos en este proyecto nos permiten ser muy optimistas con el uso de esta herramienta y nos animan a continuar en la misma línea. El profesorado participante se ha mostrado dispuesto a continuar empleando esta TIC en su docencia, tratando de abarcar más asignaturas, diversificar el tipo de pruebas, y emplear los mandos de respuesta en grupo completo, cuando el número de alumnos lo permita. La puesta en común de los resultados revela que, de forma general, este tipo de sistemas de respuesta incrementa el nivel de atención del alumnado, ya que se les demanda de forma continuada su participación activa durante la sesión. Se potencia la retención de conceptos, al suministrar en el acto la respuesta correcta a cada pregunta realizada. Permite también al profesorado conocer el nivel previo de conocimientos sobre la materia a impartir, ya que se puede realizar este tipo de preguntas al comienzo de la sesión y enfocar entonces su atención en las debilidades manifestadas. Asimismo se puede testar el grado de adquisición de dichos conocimientos, realizando este tipo de cuestionarios después de la sesión. Además, el tratamiento posterior de los resultados, de forma individualizada, permite gestionar de forma ágil el nivel de conocimientos y adquisición de competencias en lo que es un sistema de evaluación continua, tan necesario en los nuevos enfoques metodológicos nacidos de la implantación del EEES. Por último destacar que el profesorado participante ha considerado que se trata de una herramienta de gran utilidad para la consecución del objetivo de excelencia en la docencia, que además es eficaz y de fácil manejo, y entiende que no debe ser una actividad puntual, sino un proceso transformador en la actividad docente e interacción alumno-profesor, configurándose como una herramienta habitual en los sistemas de enseñanza-aprendizaje.Implementation of the new degrees in the EHEA involve a new methodological approach, but above all evaluation. The teacher should strive to be able to assess not only the level of knowledge of the students on the content, as the current society demands a profile of the most complete graduates based on training by competencies. The acquisition of both facets by students is based mainly on face-to-face activities and teaching methodologies applied in the development of the subjects, both in small group and in whole group. Therefore, any additional tool that helps the teacher to facilitate this double task is well received, since it will allow to evaluate the overall academic performance of the students. Recently the Faculty of Sciences has launched a pilot experience through which a large group of teachers has incorporated into their teaching a system of interactive response devices. Currently, the Faculty of Sciences has a total of 82 wireless response controllers and three receiving antennas. This new technology has enabled the teacher to interact interactively with the students and collect the individual answers immediately. The results obtained in this project allow us to be very optimistic with the use of this tool and encourage us to continue in the same line. The participating teachers have been willing to continue using this ICT in their teaching, trying to cover more subjects, diversify the type of tests, and use the full group response commands, when the number of students allows. The sharing of results reveals that, in a general way, this type of response systems increases the level of attention of the students, since they are continuously demanded their active participation during the session. The retention of concepts is strengthened by providing the correct answer to every question asked. It also allows the faculty to know the previous level of knowledge about the subject to be taught, since this type of questions can be asked at the beginning of the session and then focus their attention on the weaknesses manifested. It is also possible to test the degree of acquisition of this knowledge, performing this type of questionnaire after the session. In addition, the subsequent treatment of the results, in an individualized way, allows to manage in an agile way the level of knowledge and acquisition of competences in what is a system of continuous evaluation, so necessary in the new methodological approaches born from the implantation of the EHEA. Finally, it should be pointed out that the participating teachers have considered that this is a very useful tool for achieving the objective of excellence in teaching, which is also efficient and easy to use and understands that it should not be a specific activity, but a transforming process in the teaching activity and student-teacher interaction, being configured as a habitual tool in the teaching-learning systems
Characteristics and Outcomes in Patients With COVID-19 and Acute Ischemic Stroke: The Global COVID-19 Stroke Registry.
Recent case-series of small size implied a pathophysiological association between coronavirus disease 2019 (COVID-19) and severe large-vessel acute ischemic stroke. Given that severe strokes are typically associated with poor prognosis and can be very efficiently treated with recanalization techniques, confirmation of this putative association is urgently warranted in a large representative patient cohort to alert stroke clinicians, and inform pre- and in-hospital acute stroke patient pathways. We pooled all consecutive patients hospitalized with laboratory-confirmed COVID-19 and acute ischemic stroke in 28 sites from 16 countries. To assess whether stroke severity and outcomes (assessed at discharge or at the latest assessment for those patients still hospitalized) in patients with acute ischemic stroke are different between patients with COVID-19 and non-COVID-19, we performed 1:1 propensity score matching analyses of our COVID-19 patients with non-COVID-19 patients registered in the Acute Stroke Registry and Analysis of Lausanne Registry between 2003 and 2019. Between January 27, 2020, and May 19, 2020, 174 patients (median age 71.2 years; 37.9% females) with COVID-19 and acute ischemic stroke were hospitalized (median of 12 patients per site). The median National Institutes of Health Stroke Scale was 10 (interquartile range [IQR], 4-18). In the 1:1 matched sample of 336 patients with COVID-19 and non-COVID-19, the median National Institutes of Health Stroke Scale was higher in patients with COVID-19 (10 [IQR, 4-18] versus 6 [IQR, 3-14]), P=0.03; (odds ratio, 1.69 [95% CI, 1.08-2.65] for higher National Institutes of Health Stroke Scale score). There were 48 (27.6%) deaths, of which 22 were attributed to COVID-19 and 26 to stroke. Among 96 survivors with available information about disability status, 49 (51%) had severe disability at discharge. In the propensity score-matched population (n=330), patients with COVID-19 had higher risk for severe disability (median mRS 4 [IQR, 2-6] versus 2 [IQR, 1-4], P<0.001) and death (odds ratio, 4.3 [95% CI, 2.22-8.30]) compared with patients without COVID-19. Our findings suggest that COVID-19 associated ischemic strokes are more severe with worse functional outcome and higher mortality than non-COVID-19 ischemic strokes
Vulnerabilidade para a ocorrência de fasciolose na área experimental do Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo, IFES, Alegre, ES
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