166 research outputs found
Pie diabético. Hallazgos en la RM
The diabetes mellitus is a systemic disease with a 5% rate of occurrence in the general population. It is cause significant morbility in the foot and ankle due to vascular disease, Neuropathy and infection. The MRI is essential to the diagnosis and evaluation of arthritis, osteomyelitis, neuropathic osteoarthropathy, cellulitis, ulcers and abscesses.La diabetes mellitus es una enfermedad sistémica con una incidencia del 5% en la población general. Puede afectar a múltiples órganos causando significativa morbilidad en el pie debido a enfermedad vascular, neuropatía e infección. La RM es imprescindible para el diagnóstico y valoración de la artritis, osteomielitis, osteoartropatía neuropática, celulitis, úlceras y abscesos
Fracturas de estrés de los metatarsianos
Stress fractures of metatarsals may occur in some bones but it is quite common in the metatarsals bones of the feet. Stress fracture can be produced in normal or anormal bones, which are subjected to ciclical repeated loads of low intensitiy. There are two kinds of stress fractures: fatigue fractures that are caused by anormal stress or torsion in bone with normal elastic strength, and insuficiency fractures, that are caused when normal stress affects bones with deficiency elastic strenght. The most common localization is the neck of the second and third metatarsal.Generally these fractures have a specific clinic, which allow us to diagnose them. However if we are not able to diagnose them, we may use radiograph, CT, MRI and/or gammagraphy, in order to obtain an early diagnosis, as has been described in the above-mentioned clinical cases.Las fracturas de estrés pueden ocurrir en cualquier hueso, siendo muy frecuentes en los metatarsianos. Pueden producirse en huesos normales, ó alterados, que están sometidos a cargas cíclicas repetidas de menor intensidad que las que causan la fractura aguda del hueso. Se distinguen dos tipos de fractura de estrés: la fractura por fatiga, que se produce como consecuencia de la aplicación de un estrés anormal ó torsión sobre un hueso con resistencia elástica normal, y la fractura por insuficiencia, que se presenta cuando el estrés normal tiene lugar en un hueso con resistencia elástica deficiente. La localización más frecuente de estas fracturas es en el cuello del segundo y tercer metatarsiano. La exploración clínica nos permite sugerir su diagnóstico, y tras la realización en todo caso de RX simple, en aquellas ocasiones de clínica insidiosa con RX simple negativa ó poco concluyente la realización de Tac, RM y/ó gammagrafía, permiten un diagnóstico precoz y/ó evolutivo, tal como mostramos en los casos clínicos expuestos
Polar decomposition of the Mueller matrix: a polarimetric rule of thumb for square-profile surface structure recognition
In this research, the polar decomposition (PD) method is applied to experimental Mueller matrices (MMs) measured on two-dimensional microstructured surfaces. Polarization information is expressed through a set of parameters of easier physical interpretation. It is shown that evaluating the first derivative of the retardation parameter, δ, a clear indication of the presence of defects either built on or dug in the scattering flat surface (a silicon wafer in our case) can be obtained. Although the rule of thumb thus obtained is established through PD, it can be easily implemented on conventional surface polarimetry. These results constitute an example of the capabilities of the PD approach to MM analysis, and show a direct application in surface characterization
Polar decomposition of Mueller matrices for 2D-structured surfaces
In this research, the Polar Decomposition (PD) has been applied to the Mueller matrices (MMs) of the light scattered by linear ribs of rectangular profile on a flat substrate. Although photo-lithographic technique produces a silicon surface, metallic character is acquired by sputtering with gold some of the samples. With a dual rotating compensator polarimeter the MMs are obtained by Fourier Transform analysis. The samples have been numerically modeled by using both FDTD and Extinction Theorem (ET) and MMs have been computed
from the results. The scattering depends strongly on the geometry and composition of the ribs, and this sensitivity is noticed for instance in M11 element. But information offered by PD parameters is shown to be more apprehensible, like the substrate-induced depolarization or the retardance associated to the rib width.This research has been supported by the Ministry of Education of Spain under project FIS2007-60158 and by USAITCA through R&D 1390-PH-01
Creación de un índice de citas de revistas españolas de Humanidades para el estudio de la actividad investigadora de los científicos de estas disciplinas
Los estudios bibliométricos basados en el análisis de citaciones han demostrado tener un gran interés, puesto que permiten evaluar la actividadcientífica desde distintas perspectivas. Sin embargo, su utilización entraña el problema del acceso a fuentes que proporcionen los datos necesarios sobre la bibliografía referenciada por los autores en sus trabajos, pues rara vezlos incluyen las bases de datos. El Institute for Scientific Information (ISI) es la única institución que produce bases de datos con las referencias bibliográficas de los documentos que indizan (Science Citation Index, SocialSciences Citation Index y Arts & Humanities Citation Index). Sin embargo,estas bases de datos tienen una escasa cobertura de las publicaciones editadas por países no anglosajones, especialmente en las áreas de humanidades.Por ello, un equipo multidisciplinar de la Universidad Carlos III de Madrid emprendió un proyecto piloto dirigido a crear un índice de citas de revistas españolas de humanidades, concretamente en el área de Historia, con el fin de analizar distintos aspectos vinculados con la actividad científica en esta disciplina, como autores y fuentes más citadas, la tipología documental utilizada por este colectivo, la obsolescencia de la información, o su capacidad idiomática. Estos aspectos se analizaron a partir de la información obtenida de las casi 25.000 referencias bibliográficas de revistas de españolas de Historia seleccionadas, durante los años 1997 y 1998.Bibliometric studies based on the analysis of citations have proved
interesting in the evaluation of scientific activity from different perspectives.
Their use, however, depends on access to data on the bibliography referenced
by authors in their papers, information that is rarely included in
databases. In fact, the Institute for Scientific Information (ISI) is the only
institution whose databases contain the bibliographic references cited in the
papers indexed (Science Citation Index, Social Sciences Citation Index and
Arts & Humanities Citation Index) and their coverage of scientific literature
published outside Anglo-Saxon countries is limited, particularly in the
area of humanities. For this reason, a multidisciplinary group at Madrid’s Carlos III University
undertook a pilot project designed to create a citation index of Spanish
humanities journals, specifically in the area of History, to analyse a
number of aspects relating to scientific activity in this discipline, such as
the authors and sources most often cited, typology of the documentation
used, obsolescence of the information or their knowledge of languages. These
issues were analysed based on nearly 25.000 bibliographic references cited
in papers published by selected Spanish history journals in 1997 and
1998
Use of maraviroc in patients with undetectable viral load: efficacy, tolerance and predictors of viral response in MARAVIROC-cohort study
Introduction: No controlled clinical trials had studied the role of maraviroc (MRV) in fully suppressed patients [1].
Methods and Materials: MRV-cohort is an observational, retrospective, multicentric (27 sites) large cohort study of patients
starting MRV in clinical practice under different circumstances, with at least 48 weeks of follow-up. For the present analysis we
selected all those patients starting with an HIV-RNAB50 copies/mL. Demographics, baseline CD4 cell count, past history of
antiretroviral treatment (ART), tropism, reasons for MRV use, MRV based therapy and change/end of MRV use were assessed.
Paired analysis of lipid, hepatic and kidney profile changes and univariate and multivariate analyses of HIV-RNAB50 copies/mL
at 48 weeks were explored.
Results: We included 247 out of 667 subjects from the entire cohort. At study entry, their median age was 47 years, 23% were
women, 31% MSM, 49% had CDC category C, median CD4 counts were 468 cells/mm3
, 46% were HCV and 4.5% AgHBs.
Tropism information was available in 197 (94% R5). Median length of prior ARTV was 10.7 years, with exposure to a median of
three drug families. Main reasons for prescribing MRV were: toxicity 38%, inmunodiscordance 23%, simplification 19% and
admission in a clinical trial 10.4%. MRV based therapies used were MRV2NRTIs 9%, MRVPI 46%, MRVPIother 40% and
MRVother 5%. At 48 weeks, 23% of patients had changed or finished MRV therapy due to toxicity 2.4%, virological failure 2%,
immunological failure 1.2%, simplification 3,2%, trial requirement 9.7%, medical decision 2.8%, treatment suspension 1.2% and
unknown 0.4%. At 48 weeks, no significant changes were observed in lipid, hepatic or kidney profiles, and 85% of patients
remained with HIV-RNAB50 copies/mL. Focusing on viral response univariate and multivariate models did not show any
significant baseline variable explaining viral failure.
Conclusions: In clinical practice MRV was used, mostly in R5 positive patients, with adequate efficacy and tolerance, but
important number of patients changed due to non-clinical reasons. In this scenario neither reason for use of MRV nor MRVbased
therapy explained viral failure
A Multiple Stakeholder Multicriteria Decision Analysis in Diabetic Macular Edema Management: The MULTIDEX‑EMD Study
Background The clinical and economic management of retinal diseases has become more complex following the introduction of new intravitreal treatments. Multicriteria decision analysis (MCDA) offers the potential to overcome the challenges associated with traditional decision-making tools. Objectives A MCDA to determine the most relevant criteria to decision-making in the management of diabetic macular edema (DME) based on the perspectives of multiple stakeholders in Spain was developed. This MCDA was termed the MULTIDEX-EMD study. Methods Nineteen stakeholders (7 physicians, 4 pharmacists, 5 health authorities and health management experts, 1 psychologist, and 2 patient representatives) participated in this three-phase project. In phase A, an advisory board defined all of the criteria that could influence DME treatment decision-making. These criteria were then screened using a discrete choice experiment (DCE) (phase B). Next, a multinomial logit model was fitted by applying the backward elimination algorithm (relevant criteria: p value = 15 letters (p value < 0.001), effect duration per administration (p value = 0.008), retinal detachment (p value < 0.001), endophthalmitis (p value = 0.012), myocardial infarction (p value < 0.001), intravitreal hemorrhage (p value = 0.021), annual treatment cost per patient (p value = 0.001), health-related quality of life (HRQoL) (p value = 0.004), and disability level (p value = 0.021). Conclusions From a multi-stakeholder perspective, the selection of an appropriate treatment for DME patients should guarantee patient safety and maximize the visual acuity improvement and treatment effect duration. It should also contribute to system sustainability by being affordable, it should have a positive impact on HRQoL, and it should prevent disability
Polarimetric techniques for determining morphology and optical features of High Refractive Index dielectric nanoparticles size
The spectral evolution of the degree of linear polarization (PL) at a scattering angle of 90º is studied numerically for high refractive index (HRI) dielectric spherical nanoparticles. The behaviour of PL(90º) is analyzed as a function of the refractive index of the surrounding medium and the particle radius. We focus on the spectral region where both electric and magnetic resonances of order not higher than two are located for various semiconductor materials with low absorption. The spectral behavior of PL(90º) has only a small, linear dependence on nanoparticle size R. This weak dependence makes it experimentally feasible to perform real-time retrievals of both the refractive index of the external medium and the NP size R. From an industrial point of view, pure materials are nonrealistic, since they can only be provided under certain conditions. For this reason, we also study the effect of contaminants on the resonances of silicon NPs by considering the spectral evolution of PL(90º).This research was supported by MICINN (Spanish Ministry of Science and Innovation, project FIS2013-45854-P)
Contabilidad ambiental. antecedentes internacionales
La Contabilidad Nacional trata de establecer una medida aproximada del bienestar que
disfruta la población sin considerar el papel que desempeña el medio ambiente en la
calidad de vida de la sociedad. Un grupo de organizaciones de ámbito supranacional y de
países se hicieron eco de esta deficiencia y desarrollaron una serie de propuestas
operativas para recoger información sobre el estado del medio ambiente y sus vínculos
con el sistema económico. Los sistemas propuestos difieren en cada caso pudiendo
diferenciarse cinco categorías: los sistemas de indicadores, los indicadores agregados,
las cuentas de recursos naturales, las cuentas satélite y los sistemas de contabilidad
integrada. Siguiendo esta clasificación, en el artículo se presentan algunas de las
experiencias desarrolladas fundamentalmente a escala nacional. La inclusión de un país
en alguna de las categorías no implica que se desarrolle de forma exclusiva un único
sistema, siendo posible la coexistencia de sistemas complementarios
Chondroid Tumors: Review of Salient Imaging Features and Update on the WHO Classification
Chondrogenic tumors are typically well recognized on radiographs, but differentiation between benign and malignant cartilaginous lesions can be difficult both for the radiologist and for the pathologist. Diagnosis is based on a combination of clinical, radiological and histological findings. While treatment of benign lesions does not require surgery, the only curative treatment for chondrosarcoma is resection. This article (1) emphasizes the update of the WHO classification and its diagnostic and clinical effects; (2) describes the imaging features of the various types of cartilaginous tumors, highlighting findings that can help differentiate benign from malignant lesions; (3) presents differential diagnoses; and (4) provides pathologic correlation. We attempt to offer valuable clues in the approach to this vast entit
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