87 research outputs found
Clustering transition in a system of particles self-consistently driven by a shear flow
We introduce a simple model of active transport for an ensemble of particles
driven by an external shear flow. Active refers to the fact that the flow of
the particles is modified by the distribution of particles itself. The model
consists in that the effective velocity of every particle is given by the
average of the external flow velocities felt by the particles located at a
distance less than a typical radius, . Numerical analysis reveals the
existence of a transition to clustering depending on the parameters of the
external flow and on . A continuum description in terms of the number
density of particles is derived, and a linear stability analysis of the density
equation is performed in order to characterize the transitions observed in the
model of interacting particles.Comment: 11 pages, 2 figures. To appear in PR
Diffusive transport and self-consistent dynamics in coupled maps
The study of diffusion in Hamiltonian systems has been a problem of interest
for a number of years.
In this paper we explore the influence of self-consistency on the diffusion
properties of systems described by coupled symplectic maps. Self-consistency,
i.e. the back-influence of the transported quantity on the velocity field of
the driving flow, despite of its critical importance, is usually overlooked in
the description of realistic systems, for example in plasma physics. We propose
a class of self-consistent models consisting of an ensemble of maps globally
coupled through a mean field. Depending on the kind of coupling, two different
general types of self-consistent maps are considered: maps coupled to the field
only through the phase, and fully coupled maps, i.e. through the phase and the
amplitude of the external field. The analogies and differences of the diffusion
properties of these two kinds of maps are discussed in detail.Comment: 13 pages, 14 figure
Cuando se abandona y pasa en completo olvido la materia y objeto propio de una cuestion, y se recurre al ataque directo y esclusivo [sic] de las personas, se dá bastante á conocer, que por falta de razones, se ha querido usar del reprobado medio de la injuria ..
Se trata de la vindicación de Rafael Lorenzo García, miembro del comité del partido progresista, contra los ataques que se le hicieron por parte Cristóbal del Castillo, Rafael Massieu y otros miembros del partido moderado de Las Palmas, defensores de la candidatura de Bertran de LisLugar de imp. tomado de VicayaTexto fechado el 27 de noviembre de 185
Incidence of long-term cardiotoxicity and evolution of the systolic function in patients with breast cancer treated with anthracyclines
Background: Anthracycline cardiotoxicity (AC) may manifest years after treatment (long-term cardiotoxicity). There is little data on the incidence and natural history of AC in the current context, with protocols including lower anthracycline doses. The present study prospectively evaluated the incidence, time of occurrence and clinical correlates of long-term cardiotoxicity and the evolution of systolic function in patients with breast cancer treated with anthracyclines.
Methods: This study prospectively included 85 consecutive patients undergoing chemotherapy (CHT) with anthracyclines without trastuzumab. All patients underwent evaluation at baseline, at the end of CHT, 3 months after the end of CHT and 1 and 4 years subsequent to the beginning of CHT. Clinical data and echocardiographic parameters were evaluated in all examinations.
Results: The mean dose of doxorubicin used was 243.53 mg/m2. Median follow-up of the current cohort was 4.5 years. At 1 year the incidence of AC was 1% and at the end of the follow-up 16.5% (14 of 85 patients). Therefore, the incidence of long-term cardiotoxicity was 15%. Of these 14 patients with AC, 12 had asymptomatic systolic dysfunction, 1 had heart failure and 1 suffered sudden death. Fifteen percent developed systolic dysfunction during follow–up. An early decline in strain was observed in patients who developed long-term AC.
Conclusions: The incidence of long-term cardiotoxicity in patients treated with low-cumulative dose of anthracyclines is high, 16.5% at 4.5 years. This was observed in almost all cases after the first year of follow-up. Therefore, long-term monitoring may be advisable
[Sobre la separación de Juan Persiva, Diputado por Las Palmas, de la Diputación Provincial
Tít. y mención de responsabilidad tomado del propio texto que no tiene tít.Datos de imp. tomados del colofó
Diastolic dysfunction following anthracycline-based chemotherapy in breast cancer patients: incidence and predictors
[Abstract] INTRODUCTION:
Cardiotoxicity represents a major limitation for the use of anthracyclines or trastuzumab in breast cancer patients. Data from longitudinal studies of diastolic dysfunction (DD) in this group of patients are scarce. The objective of the present study was to assess the incidence, evolution, and predictors of DD in patients with breast cancer treated with anthracyclines.
METHODS:
This analytical, observational cohort study comprised 100 consecutive patients receiving anthracycline-based chemotherapy (CHT) for breast cancer. All patients underwent clinical evaluation, echocardiogram, and measurement of cardiac biomarkers at baseline, end of anthracycline-based CHT, and at 3 months and 9 months after anthracycline-based CHT was completed. Fifteen patients receiving trastuzumab were followed with two additional visits at 6 and 12 months after the last dose of anthracycline-based CHT. A multivariate analysis was performed to find variables related to the development of DD. Fifteen of the 100 patients had baseline DD and were excluded from this analysis.
RESULTS:
At the end of follow-up (median: 12 months, interquartile range: 11.1-12.8), 49 patients (57.6%) developed DD. DD was persistent in 36 (73%) but reversible in the remaining 13 patients (27%). Four patients developed cardiotoxicity (three patients had left ventricular systolic dysfunction and one suffered a sudden cardiac death). None of the patients with normal diastolic function developed systolic dysfunction during follow-up. In the logistic regression model, body mass index (BMI) and age were independently related to the development of DD, with the following odds ratio values: BMI: 1.19 (95% confidence interval [CI]: 1.04-1.36), and age: 1.12 (95% CI: 1.03-1.19). Neither cardiac biomarkers nor remaining clinical variables were predictors of DD.
CONCLUSION:
Development of diastolic dysfunction after treatment with anthracycline or anthracycline- plus trastuzumab chemotherapy is common. BMI and age were independently associated with DD following anthracycline chemotherapy.Instituto de Salud Carlos III; RD06/0014/002Instituto de Salud Carlos III; RD12/0042/006
Using XAI in the Clock Drawing Test to reveal the cognitive impairment pattern.
he prevalence of dementia is currently increasing worldwide. This syndrome produces a deteriorationin cognitive function that cannot be reverted. However, an early diagnosis can be crucial for slowing itsprogress. The Clock Drawing Test (CDT) is a widely used paper-and-pencil test for cognitive assessmentin which an individual has to manually draw a clock on a paper. There are a lot of scoring systems forthis test and most of them depend on the subjective assessment of the expert. This study proposes acomputer-aided diagnosis (CAD) system based on artificial intelligence (AI) methods to analyze the CDTand obtain an automatic diagnosis of cognitive impairment (CI). This system employs a preprocessingpipeline in which the clock is detected, centered and binarized to decrease the computational burden.Then, the resulting image is fed into a Convolutional Neural Network (CNN) to identify the informativepatterns within the CDT drawings that are relevant for the assessment of the patient’s cognitive status.Performance is evaluated in a real context where patients with CI and controls have been classified byclinical experts in a balanced sample size of 3282 drawings. The proposed method provides an accuracyof 75.65% in the binary case-control classification task, with an AUC of 0.83. These results are indeedrelevant considering the use of the classic version of the CDT. The large size of the sample suggests thatthe method proposed has a high reliability to be used in clinical contexts and demonstrates the suitabilityof CAD systems in the CDT assessment process. Explainable artificial intelligence (XAI) methods areapplied to identify the most relevant regions during classification. Finding these patterns is extremelyhelpful to understand the brain damage caused by CI. A validation method using resubstitution withupper bound correction in a machine learning approach is also discusseThis work was supported by the MCIN/ AEI/10.13039/501100011033/ and FEDER “Una manera de hacer Europa” under the RTI2018- 098913-B100 project, by the Consejeria de Economia, Innovacion, Ciencia y Empleo (Junta de An765 dalucia) and FEDER under CV20-45250, A-TIC080-UGR18, B-TIC-586-UGR20 and P20-00525 projects, and by the Ministerio de Universidades under the FPU18/04902 grant given to C. JimenezMesa and the Margarita-Salas grant to J.E. Arco
Diseño, producción y evaluación de un entorno telemático para la formación y reflexión del profesorado universitario en la implantación del Espacio Europeo de Educación Superior
Transferencias directas a escuelas : reflexiones sobre prácticas en América Latina
Recursos financieros descentralizados para escuelas públicas del Brasil. Una política necesaria -- Chile: la experiencia de la Subvención Escolar Preferencial -- PRONADE, un modelo innovador en Guatemala -- El Programa Hondureño de Educación Comunitaria -- Programa Escuelas Autónomas en Nicaragua. Lecciones de una experiencia -- Modelos y prácticas de transferencias directas a escuelas: reflexiones sobre experiencias latinoamericanas .Este libro se concentra en programas de transferencia de recursos financieros desde una unidad central de la administración pública educativa hacia los establecimientos escolares, donde se descentraliza la competencia de gestión y uso de los fondos transferidos. En América Latina, a lo largo de las últimas dos décadas, varios programas de subvención escolar se han implementado con el propósito de lograr una asignación más eficiente del gasto público, ampliar la capacidad del Estado, expandir la oferta educativa y alcanzar a poblaciones excluidas. El análisis de los casos reunidos en esta publicación pone en cuestión la eficacia de esta herramienta de política con respecto al mejoramiento de la calidad educativa. Las experiencias latinoamericanas de subvención escolar brindan ejemplos de las oportunidades abiertas por distintos programas en el corto plazo y los desafíos que conlleva su implementación a lo largo del tiempo, y convocan a analistas y responsables de decisiones a construir una visión dinámica de la política educativa, que permita anticipar y, sobre todo, enfrentar problemas que emergen como consecuencia de acciones pasadas. La experiencia acumulada en la región invita a analizar estos programas, evaluar sus potencialidades y limitaciones, y explorar alternativas
Acaba de llegar á nuestras manos un papel suscrito por los Señores D. Rafael Lorenzo García, D. Mariano Vazquez y Bustamante, D. Manuel Pestana, D. Bartolomé Gonzalez, D. Serafin Zumbado y D. Manuel Rodriguez y Martinez en el cual se acusa á los que sostienen la candidatura del Excmo. Sr. D. Manuel Bertran de Lis de pertenecer al partido absolutista ..
Se trata del manifiesto contra el comité del Partido Progresista de Las Palmas formado por Rafael Lorenzo García, Mariano Vázquez Bustamante, Manuel Pestana, y otrosTexto firmado por Cristóbal del Castillo, Rafael Massieu, Marcial Melián, Nicolás Massieu, Juan María de LeónTexto fechado en Las Palmas de Gran Canaria a 22 de noviembre de 185
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