El realismo dialéctico en la historia

La profusa obra científica –económica, sociológica, antropológica, política,filosófica, cultural, histórica y humanista– de ANTONIO GARCÍA no requiere deexaltación. Su reconocimiento trasciende el ámbito latinoamericano para situarse,en algunas áreas del saber, en las fronteras del pensamiento universal

Analysis of plasmaspheric hiss wave amplitudes inferred from low-altitude POES electron data: Technique sensitivity analysis

A novel technique capable of inferring wave amplitudes from low-altitude electron measurements from the Polar Operational Environmental Satellites (POES) spacecraft has been previously proposed to construct a global dynamic model of chorus and plasmaspheric hiss waves. In this paper we focus on plasmaspheric hiss, which is an incoherent broadband emission that plays a dominant role in the loss of energetic electrons from the inner magnetosphere. We analyze the sensitivity of the POES technique to different inputs used to infer the hiss wave amplitudes during three conjunction events with the Van Allen Probes. These amplitudes are calculated with different input models of the plasma density, wave frequency spectrum, and electron energy spectrum, and the results are compared to the wave observations from the twin Van Allen Probes. Only one parameter is varied at a time in order to isolate its effect on the output, while the two other inputs are set to the values observed by the Van Allen Probes. The results show that the predicted hiss amplitudes are most sensitive to the adopted frequency spectrum, followed by the plasma density, but they are not very sensitive to the electron energy spectrum. Moreover, the standard Gaussian representation of the wave frequency spectrum (centered at 550 Hz) peaks at frequencies that are much higher than those observed in individual cases as well as in statistical wave distributions, which produces large overestimates of the hiss wave amplitude. For this reason, a realistic statistical model of the wave frequency spectrum should be used in the POES technique to infer the plasmaspheric hiss wave intensity rather than a standard Gaussian distribution, since the former better reproduces the observed plasmaspheric hiss wave amplitudes

Physical Examination Tests for Screening and Diagnosis of Cervicogenic Headache: A Systematic Review

It has been suggested that differential diagnosis of headaches should consist of a robust subjective ex-amination and a detailed physical examination of the cervical spine. Cervicogenic headache (CGH) is a form of headache that involves referred pain from the neck. To our knowledge, no studies have sum-marized the reliability and diagnostic accuracy of physical examination tests for CGH. The aim of this study was to summarize the reliability and diagnostic accuracy of physical examination tests used to diagnose CGH. A systematic review following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines was performed in four electronic databases (MEDLINE, Web of Science, Embase and Scopus). Full text reports concerning physical tests for the diagnosis of CGH which reported the clinometric properties for assessment of CGH, were included and screened for methodological quality. Quality Appraisal for Reliability Studies (QAREL) and Quality Assessment of Studies of Diagnostic Accuracy (QUADAS-2) scores were completed to assess article quality. Eight articles were retrieved for quality assessment and data extraction. Studies investigating diagnostic reliability of physical exami-nation tests for CGH scored poorer on methodological quality (higher risk of bias) than those of diag-nostic accuracy. There is sufficient evidence showing high levels of reliability and diagnostic accuracy of the selected physical examination tests for the diagnosis of CGH. The cervical flexion-rotation test (CFRT) exhibited both the highest reliability and the strongest diagnostic accuracy for the diagnosis of CGH

Neurologic phenotype of Schimke immuno-osseous dysplasia and neurodevelopmental expression of SMARCAL1

Schimke immuno-osseous dysplasia (OMIM 242900) is an uncommon autosomal-recessive multisystem disease caused by mutations in SMARCAL1 (swi/snf-related, matrix-associated, actin-dependent regulator of chromatin, subfamily a-like 1), a gene encoding a putative chromatin remodeling protein. Neurologic manifestations identified to date relate to enhanced atherosclerosis and cerebrovascular disease. Based on a clinical survey, we determined that half of Schimke immuno-osseous dysplasia patients have a small head circumference, and 15% have social, language, motor, or cognitive abnormalities. Postmortem examination of 2 Schimke immuno-osseous dysplasia patients showed low brain weights and subtle brain histologic abnormalities suggestive of perturbed neuron-glial migration such as heterotopia, irregular cortical thickness, incomplete gyral formation, and poor definition of cortical layers. We found that SMARCAL1 is highly expressed in the developing and adult mouse and human brain, including neural precursors and neuronal lineage cells. These observations suggest that SMARCAL1 deficiency may influence brain development and function in addition to its previously recognized effect on cerebral circulation

Resultados de urocultivos en adultos realizados por el laboratorio de microbiología del Hospital de Clínicas - San Lorenzo de enero del 2015 a agosto de 2016 y métodos de estudio de las infecciones urinarias disponibles en la institución

Introducción: Los objetivos de este trabajo son: presentar los métodos de estudio de las infecciones urinarias actualmente disponibles en el Laboratorio de Microbiología del Hospital de Clínicas y mostrar los datos de los urocultivos evaluados en forma retrospectiva. Materiales y Métodos: Para estudiar los métodos de estudio de los urocultivos disponibles en el Laboratorio hemos recurrido al archivo del Laboratorio cuyos datos fueron consecutivamente cargados en una planilla de procesamiento de datos Excel de Microsoft Office ®. Los resultados de los urocultivos fueron evaluados de enero de 2015 a agosto de 2016, en forma retrospectiva, observacional, en corte transverso, de los adultos de ambos sexos. Las muestras para urocultivo son recibidas y procesadas en el laboratorio, siguiendo pasos preestablecidos. Resultados: El microorganismo preponderante de los urocultivos fue Escherichia coli (60% de las mujeres y 32% de los varones) seguido por Klebsiella pneumoniae (19% de los varones, 14% de las mujeres). Otros microorganismos aislados fueron Candida sp., Enterococcus faecalis, Enterobacter cloacae, Pseudomona aeruginosa, Proteus mirabilis, Staphylococcus aureus, Acinetobacter baumanii. La resistencia de Escherichia Coli a nitrofurantoína fue del 6% en los varones y 1% en las mujeres. La resistencia de E.Coli a meropenen fue también escasa. En cuanto a Klebsiella pneumoniae en las mujeres, la resistencia fue del 3%. En los hombres, los antibióticos testados para Klebsiella pneumoniae mostraron una resistencia superior al 30%, con excepción del meropenem. Uropatógenos productores de betalactamas de espectro extentido (BLEE) y de carbapenemasas fueron detectados en el presente estudio. Discusión: La toma de la orina para el urocultivo se efectúa siguiendo pautas claras, emanadas del laboratorio. Con la utilización de medios actualmente disponibles en el laboratorio, es posible tipificar el género y la especie tanto de bacterias Gram negativas y positivas como de hongos. Conclusión: La estructura del Laboratorio de Microbiología ha tenido avances que permiten la identificación precisa de los gérmenes de los urocultivos, así como la prevalencia y la resistencia que presentan a ciertos antibióticos. Estos aportes son particularmente útiles para los casos de Escherichia coli y Klebsiella pneumoniae debido a su alta prevalencia. También fue factible constatar la emergencia de gérmenes productores de betalactamasas de espectro extendido (BLEE) y carbapenemasas