1,996 research outputs found
Halo abundances within the cosmic web
We investigate the dependence of the mass function of dark-matter haloes on
their environment within the cosmic web of large-scale structure. A dependence
of the halo mass function on large-scale mean density is a standard element of
cosmological theory, allowing mass-dependent biasing to be understood via the
peak-background split. On the assumption of a Gaussian density field, this
analysis can be extended to ask how the mass function depends on the
geometrical environment: clusters, filaments, sheets and voids, as classified
via the tidal tensor (the Hessian matrix of the gravitational potential). In
linear theory, the problem can be solved exactly, and the result is
attractively simple: the conditional mass function has no explicit dependence
on the local tidal field, and is a function only of the local density on the
filtering scale used to define the tidal tensor. There is nevertheless a strong
implicit predicted dependence on geometrical environment, because the local
density couples statistically to the derivatives of the potential. We compute
the predictions of this model and study the limits of their validity by
comparing them to results deduced empirically from -body simulations. We
have verified that, to a good approximation, the abundance of haloes in
different environments depends only on their densities, and not on their tidal
structure. In this sense we find relative differences between halo abundances
in different environments with the same density which are smaller than 13%.
Furthermore, for sufficiently large filtering scales, the agreement with the
theoretical prediction is good, although there are important deviations from
the Gaussian prediction at small, non-linear scales. We discuss how to obtain
improved predictions in this regime, using the 'effective-universe' approach.Comment: 14 pages, 6 figures. Revision matching journal versio
ON THE COMPARISON OF TIME SERIES USING SUBSAMPLING
In this paper we propose a procedure based on the subsampling techniques for the comparison of stationary time series that are not necessarily independent. We study a test based on the Euclidean distance between the autocorrelation functions of two series. Consistency of the proposed method is established. We present a Monte Carlo study with the size and the power of the proposed test.
Discriminant analysis of multivariate time series using wavelets
In analyzing ECG data, the main aim is to differentiate between the signal patterns of those of healthy subjects and those of individuals with specific heart conditions. We propose an approach for classifying multivariate ECG signals based on discriminant and wavelet analyzes. For this purpose we use multiple-scale wavelet variances and wavelet correlations to distinguish between the patterns of multivariate ECG signals based on the variability of the individual components of each ECG signal and the relationships between every pair of these components. Using the results of other ECG classification studies in the literature as references, we demonstrate that our approach applied to 12-lead ECG signals from a particular database, displays quite favourable performance. We also demonstrate with real and synthetic ECG data that our approach to classifying multivariate time series out performs other well-known approaches for classifying multivariate time series. In simulation studies using multivariate time series that have patterns that are different from that of the ECG signals, we also demonstrate very favourably performance of this approach when compared to these other approaches.Time series, Wavelet Variances, Wavelet Correlations, Discriminant Analysis
Discriminant analysis of multivariate time series using wavelets
In analyzing ECG data, the main aim is to differentiate between the signal patterns
of those of healthy subjects and those of individuals with specific heart conditions.
We propose an approach for classifying multivariate ECG signals based on
discriminant and wavelet analyzes. For this purpose we use multiple-scale wavelet
variances and wavelet correlations to distinguish between the patterns of
multivariate ECG signals based on the variability of the individual components of
each ECG signal and the relationships between every pair of these components.
Using the results of other ECG classification studies in the literature as references,
we demonstrate that our approach applied to 12-lead ECG signals from a particular
database, displays quite favourable performance. We also demonstrate with real
and synthetic ECG data that our approach to classifying multivariate time series out
performs other well-known approaches for classifying multivariate time series. In
simulation studies using multivariate time series that have patterns that are different
from that of the ECG signals, we also demonstrate very favourably performance of
this approach when compared to these other approaches
Family-specific degenerate primer design: a tool to design consensus degenerated oligonucleotides
Designing degenerate PCR primers for templates of unknown nucleotide sequence may be a very difficult task. In this paper, we present a new method to design degenerate primers, implemented in family-specific degenerate primer design (FAS-DPD) computer software, for which the starting point is a multiple alignment of related amino acids or nucleotide sequences. To assess their efficiency, four different genome collections were used, covering a wide range of genomic lengths: Arenavirus ( nucleotides), Baculovirus ( to bp), Lactobacillus sp. ( to bp), and Pseudomonas sp. ( to bp). In each case, FAS-DPD designed primers were tested computationally to measure specificity. Designed primers for Arenavirus and Baculovirus were tested experimentally. The method presented here is useful for designing degenerate primers on collections of related protein sequences, allowing detection of new family members.Fil: Iserte, Javier Alonso. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área de Virosis Emergentes y Zoonótica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Stephan, Betina Inés. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área de Virosis Emergentes y Zoonótica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Goñi, Sandra Elizabeth. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área de Virosis Emergentes y Zoonótica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Borio, Cristina Silvia. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área de Virosis Emergentes y Zoonótica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ghiringhelli, Pablo Daniel. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área Virus de Insectos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lozano, Mario Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área de Virosis Emergentes y Zoonótica; Argentin
Conocimiento y aplicación del Código Paciente Politraumático o Traumático Grave en urgencias por parte del personal de enfermería
Màster en Infermeria d'Urgències Hospitalàries, Universitat de Barcelona, Escola Universitària d'Infermeria, any: 2012-2013, Director: Joan Maria Estrada Masllorens. Tutora: Sandra Cabrera JaimeIntroducción: Dada la incidencia de pacientes politraumáticos que se presentan a diario en nuestra sociedad, se crea un código de actuación llamado “paciente politraumático y traumático grave”, con el objetivo de mejorar la manera como se atienden las lesiones de estos pacientes y reducir el tiempo que se necesita para iniciar las intervenciones adecuadas a sus necesidades. Objetivo principal: Valorar los conocimientos acerca del código paciente politraumático y traumático grave (PPT) en los profesionales de enfermería de los servicios de urgencias de la especialidad de traumatología en los hospitales: Vall d’Hebrón, Bellvitge y Clínic durante el año 2014. Ámbito y sujetos de estudio: El estudio se realizará durante los años 2013 y 2014 en los siguientes hospitales: Bellvitge, Vall d’Hebrón y Clínic. Se tomará como muestra todo el personal de enfermería del servicio de urgencias de dichos hospitales. Diseño: Estudio observacional descriptivo transversal, paradigma positivista. Variables: Grado de conocimientos, experiencia profesional, comunicación, antigüedad, número de códigos asistidos, tipo de hospital, edad, especialidad en urgencias. Recogida de datos: Se realizará una encuesta ad-hoc, que consta de 26 preguntas, la administración será directa, el cuestionario será autocumplimentado, anónimo y pilotado; los cuestionarios se repartirán durante un periodo total de un año por los propios encuestadores. Análisis de datos: Los encuestadores del estudio serán los responsables de realizar el análisis de los resultados, será procesado mediante el paquete estadístico SPSS versión 17.0 y Excel de Microsoft. Una vez recogidos los datos se realizará un análisis descriptivo univariante de la muestra reclutada utilizando la mediana, moda y desviación típica en el caso de las variables cuantitativas. Para variables cualitativas se realizará un análisis inferencial bivariante, en que se utilizará la prueba de chi-cuadrado; y la prueba de la Anova en caso de relaciones de variables
Impact of diabetes mellitus on ventricular structure, arterial stiffness, and pulsatile hemodynamics in heart failure with preserved ejection fraction
Background-Heterogeneity in the underlying processes that contribute to heart failure with preserved ejection fraction (HFpEF) is increasingly recognized. Diabetes mellitus is a frequent comorbidity in HFpEF, but its impact on left ventricular and arterial structure and function in HFpEF is unknown. Methods and Results-Weassessed the impact of diabetesmellitus on left ventricular cellular and interstitial hypertrophy (assessedwith cardiacmagnetic resonance imaging, including T1mapping pregadolinium and postgadolinium administration), arterial stiffness (assessed with arterial tonometry), and pulsatile arterial hemodynamics (assessed with in-office pressure-flow analyses and 24-hour ambulatory monitoring) among 53 subjects with HFpEF (32 diabetic and 21 nondiabetic subjects). Despite few differences in clinical characteristics, diabetic subjects with HFpEF exhibited a markedly greater left ventricular mass index (78.1 [95% CI, 70.4-85.9] g versus 63.6 [95% CI, 55.8-71.3] g; P=0.0093) and indexed extracellular volume (23.6 [95% CI, 21.2-26.1] mL/m(2) versus 16.2 [95% CI, 13.1-19.4] mL/m(2); P=0.0008). Pronounced aortic stiffening was also observed in the diabetic group (carotid-femoral pulse wave velocity, 11.86 [95% CI, 10.4-13.1] m/s versus 8.8 [95% CI, 7.5-10.1] m/s; P=0.0027), with an adverse pulsatile hemodynamic profile characterized by increased oscillatory power (315 [95% CI, 258-373] mWversus 190 [95% CI, 144-236] mW; P=0.0007), aortic characteristic impedance (0.154 [95% CI, 0.124-0.183] mmHg/mL per second versus 0.096 [95% CI, 0.072-0.121] mm Hg/mL per second; P=0.0024), and forward (59.5 [95% CI, 52.8-66.1] mm Hg versus 40.1 [95% CI, 31.6-48.6] mm Hg; P=0.0010) and backward (19.6 [95% CI, 16.2-22.9] mm Hg versus 14.1 [95% CI, 10.9-17.3] mm Hg; P=0.0169) wave amplitude. Abnormal pulsatile hemodynamics were also evident in 24-hour ambulatory monitoring, despite the absence of significant differences in 24-hour systolic blood pressure between the groups. Conclusions-Diabetes mellitus is a key determinant of left ventricular remodeling, arterial stiffness, adverse pulsatile hemodynamics, and ventricular-arterial interactions in HFpEF
Skill Generalization Following Computer-Based Cognitive Retraining Among Individuals with Acquired Brain Injury
Individuals with acquired brain injury (ABI) often experience cognitive deficits. This creates many challenges in learning or relearning skills and generalizing skills among different contexts and task demands. Computer-Based Cognitive Retraining (CBCR) is a common intervention utilized by occupational therapists to help remediate cognitive deficits in individuals with ABI. Although research has shown that CBCR programs are effective at improving cognitive domains, there is limited evidence to support generalization of these skills to functional daily living tasks. Therefore, the primary purpose of this study was to assess the occurrence of generalizing gained skills in overall cognition, attention, and memory from a CBCR program to a medication-box task in individuals with ABI. This study utilized the Parrot Software for the CBCR intervention and evaluated changes in overall cognition, attention, and memory skills with the Montreal Cognitive Assessment (MoCA©), and generalization of those skills utilizing a performance-based medication-box task. The results indicated that the Parrot Software CBCR was effective at improving overall cognition, but not significantly in any particular cognitive domain. In addition, the gains in overall cognition failed to generalize to improved performance in the medication-box task. Extraneous variables did not affect the changes in cognition. However, participants without previous CBCR experience improved significantly when compared to participants with previous CBCR experience. Future areas of research should include interventions that can bridge the gap between CBCR and performance in daily living tasks
Complementary and Alternative Medicine: A new professional arena for Clinical Nurse Specialists and Health Educators
Abstract Complementary and Alternative Medicine (CAM) is a growing field for health professio- nals in the United States and Latin America. Since the creation of the Center for Comple- mentary and Alternative Medicine at the National Institutes of Health, new modalities of care have gained acceptance and recognition among health providers. Among health providers are nursing personnel and health educators. In the United States, the difference in the role between health educators and nursing personnel is clear. In Latin America such difference is less clear since in many countries the profession of “Health Educator” does not exist and the functions of this professional are taken by nursing personnel. This article discusses the potential role of complementary and alternative medicine for both professions. The American Holistic Nurses Association and professional associations for the certification of health educators have made a call to these health professionals to become more engaged in the understanding and practice of holistic health. Clinical emphasis on complementary and alternative medicine (CAM) can be a very viable option for clinical nurse specialists (CNS) and Health educators (HE). CAM can be a new professional are- na for these health professionals, especially for those interested in teaching future health providers. Palabras clave: Complementary and alternative medicine, nursing care, health education. Resumen La medicina complementaria y alternativa (CAM) es un área creciente para los profesiona- les de la salud en los Estados Unidos y en America Latina. Desde la creación del Centro de Medicina complementaria y alternativa de los Institutos Nacionales de Salud en los Estados Unidos, nuevas modalidades de cuidado han ganado aceptación y reconocimiento entre los proveedores de servicios de salud. Entre los proveedores de servicios de salud se encuentran el personal de enfermería y los educadores en salud. En los Estados Unidos la diferencia en el rol de los educadores en salud y el professional de enfermería es clara. En America Latina tal diferencia es menos clara ya que en muchos paises la profesión de “Educador en Salud” no existe y las funciones de éste son asumidas por el personal de enfermería. Este articulo discute el papel potencial que la medicina complementaria y alternativa tiene para las dos profesiones. La Asociación Americana de Profesionales de Enfermería Integral y las asociaciones profesionales para los Educadores en Salud en los Estados Unidos han hecho un llamado a estos profesionales de la salud para que sean más activos en el conocimiento y la práctica de la salud integral. El énfasis clinico en CAM puede ser una opción muy viable para los profesionales de enfermería clínica (CNS) y para los educadores en salud (HE). La CAM puede ser una nueva área professional para estos profesionales de la salud, y especialmente para aquellos interesados en enseñar a los proveedores de salud del futuro. Palabras clave: Medicina Complementaria y Alternativa, Cuidado de Enfermería, Educación en Salud
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