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Developing questionnaires for educational research: AMEE Guide No. 87
In this AMEE Guide, we consider the design and development of self-administered surveys, commonly called questionnaires. Questionnaires are widely employed in medical education research. Unfortunately, the processes used to develop such questionnaires vary in quality and lack consistent, rigorous standards. Consequently, the quality of the questionnaires used in medical education research is highly variable. To address this problem, this AMEE Guide presents a systematic, seven-step process for designing high-quality questionnaires, with particular emphasis on developing survey scales. These seven steps do not address all aspects of survey design, nor do they represent the only way to develop a high-quality questionnaire. Instead, these steps synthesize multiple survey design techniques and organize them into a cohesive process for questionnaire developers of all levels. Addressing each of these steps systematically will improve the probabilities that survey designers will accurately measure what they intend to measure
La función de la escritura como discurso testimonial: el Inca Garcilaso de la Vega y Miguel de Cervantes Saavedra
The present study aims to analyze and establish communicative lines of convergence and opposition between the life and work of Inca Garcilaso de la Vega and Miguel de Cervantes Saavedra, in the craft of writing as testimonial discourse. Although these two writers may appear to have different positions or interests, the value they both attach to language as to the Hispanic American culture of classical knowledge and art cannot be dismissed. Likewise, both writers belong to an important historical period, within which and from each of their geographical spaces they seek to leave in writing the ideal of a century (XVI-XVII), that is, the ideological project of their time, channeled through their own beliefs and ideas.El presente estudio tiene como objetivo analizar y establecer líneas comunicativas de convergencia y oposición entre la vida y la obra del Inca Garcilaso de la Vega y Miguel de Cervantes Saavedra, en el oficio de la escritura como discurso testimonial. Aunque estos dos escritores aparenten distintas posiciones o intereses, no puede descartarse el valor que ambos otorgan al idioma como a la cultura propiamente hispanoamericana de conocimiento y arte clásicos. Asimismo, ambos escritores pertenecen a un período histórico importante, dentro del cual y desde cada uno de sus espacios geográficos buscan dejar por escrito el ideal de un siglo (XVI-XVII), es decir, el proyecto ideológico de su tiempo, canalizado a través de sus propias creencias e ideas
La novela modernista hispanoamericana: representaciones fantasmagóricas en Fabla salvaje de César Vallejo
This article aims to analyse and explain, based on César Vallejo’s short novel Fabla salvaje, how the phantasmagorical representations in which the characters, beings and environments of the narrative are involved are constructed and developed. Likewise, for this purpose, it is necessary to recognise and start from the central idea that this novel is inscribed within the canons of the modernist movement in its version of the decadentist narrative, where man and his individual and cultural condition are condemned to misery, to moral and spiritual destruction and to the annihilation of the traditional institutions that this movement represents, such as love and fidelity. The literary analysis will use, on the one hand, narratological and hermeneutic categories based on the recognition of the textual elements, such as the narrator, space, time and the global meaning of the text; and on the other hand, it will use the categories of literary decadentism developed by Gabriela Mora.En el presente artículo se pretende analizar y explicar, a partir de la novela breve de César Vallejo, Fabla salvaje, cómo se construyen y desarrollan las representaciones fantasmagóricas en las que están envueltos los personajes, seres y ambientes de la narración. Asimismo, para este fin, es necesario reconocer y partir de la idea central que señala que esta novela está inscrita dentro de los cánones del movimiento modernista en su versión de la narrativa decadentista, donde el hombre y su condición individual y cultural están condenados a la miseria, a la destrucción moral y espiritual y al aniquilamiento de las instituciones tradicionales que este movimiento representa, como el amor y la fidelidad. El análisis literario utilizará, por un lado, categorías narratológicas y hermenéuticas que parten del reconocimiento de los elementos textuales, como el narrador, el espacio, el tiempo y el sentido global del texto; y por otro, empleará categorías propias del decadentismo literario desarrolladas por Gabriela Mora
The Problem of Contextuality and the Impossibility of Experimental Metaphysics Thereof
Recently a new impulse has been given to the experimental investigation of
contextuality. In this paper we show that for a widely used definition of
contextuality there can be no decisive experiment on the existence of
contextuality. To this end, we give a clear presentation of the hidden variable
models due to Meyer, Kent and Clifton (MKC), which would supposedly nullify the
Kochen-Specker Theorem. Although we disagree with this last statement, the
models play a significant role in the discussion on the meaning of
contextuality. In fact, we introduce a specific MKC-model of which we show that
it is non-contextual and completely in agreement with quantum mechanical
predictions. We also investigate the possibility of other definitions of
non-contextuality --with an emphasis on operational definitions-- and argue
that any useful definition relies on the specification of a theoretical
framework. It is therefore concluded that no experimental test can yield any
conclusions about contextuality on a metaphysical level
Air Pollution and Lymphocyte Phenotype Proportions in Cord Blood
Effects of air pollution on morbidity and mortality may be mediated by alterations in immune competence. In this study we examined short-term associations of air pollution exposures with lymphocyte immunophenotypes in cord blood among 1,397 deliveries in two districts of the Czech Republic. We measured fine particulate matter < 2.5 μm in diameter (PM(2.5)) and 12 polycyclic aromatic hydrocarbons (PAHs) in 24-hr samples collected by versatile air pollution samplers. Cord blood samples were analyzed using a FACSort flow cytometer to determine phenotypes of CD3(+) T-lymphocytes and their subsets CD4(+) and CD8(+), CD19(+) B-lymphocytes, and natural killer cells. The mothers were interviewed regarding sociodemographic and lifestyle factors, and medical records were abstracted for obstetric, labor and delivery characteristics. During the period 1994 to 1998, the mean daily ambient concentration of PM(2.5) was 24.8 μg/m(3) and that of PAHs was 63.5 ng/m(3). In multiple linear regression models adjusted for temperature, season, and other covariates, average PAH or PM(2.5) levels during the 14 days before birth were associated with decreases in T-lymphocyte phenotype fractions (i.e., CD3(+) CD4(+), and CD8(+)), and a clear increase in the B-lymphocyte (CD19(+)) fraction. For a 100-ng/m(3) increase in PAHs, which represented approximately two standard deviations, the percentage decrease was −3.3% [95% confidence interval (CI), −5.6 to −1.0%] for CD3(+), −3.1% (95% CI, −4.9 to −1.3%) for CD4(+), and −1.0% (95% CI, −1.8 to −0.2%) for CD8(+) cells. The corresponding increase in the CD19(+) cell proportion was 1.7% (95% CI, 0.4 to 3.0%). Associations were similar but slightly weaker for PM(2.5). Ambient air pollution may influence the relative distribution of lymphocyte immunophenotypes of the fetus
Creation of dense polymer brush layers by the controlled deposition of an amphiphilic responsive comb polymer
We introduce a copolymer with a comb topology that has been engineered to assemble in a brush configuration at an air-water interface. The molecule comprises a 6.1 kDa poly(methyl methacrylate) backbone with a statistical amount of poly[2-(dimethyl amino)ethyl methacrylate] polybase side chains averaging 2.43 per backbone.. Brush layers deposited with the hydrophobic PMMA backbone adsorbed to hydrophobized silicon are stable in water even when stored at pH values less than 2.0 for over 24 h. The use of a Langmuir trough allows a simple controlled deposition of the layers at a variety of grafting densities. Depth profiling of brush layers was performed using neutron reflectometry and reveals a significant shifting of the responsiveness of the layer upon changing the grafting density. The degree of swelling of the layers at a pH value of 4 (below the pK(b)) decreases as grafting density increases. Lowering the pH of the subphase during deposition causes the side chains to become charged and more hydrophilic extending to a brush-like configuration while at neutral pH the side chains lie in a "pancake" conformation at the interface. (C) 2009 Elsevier Ltd. All rights reserved
Anion height as a controlling parameter for the superconductivity in iron pnictides and cuprates
Both families of high superconductors, iron pnictides and cuprates,
exhibit material dependence of superconductivity. Here, we study its origin
within the spin fluctuation pairing theory based on multiorbital models that
take into account realistic band structures. For pnictides, we show that the
presence and absence of Fermi surface pockets is sensitive to the pnictogen
height measured from the iron plane due to the multiorbital nature of the
system, which is reflected to the nodeless/nodal form of the superconducting
gap and . Surprisingly, even for the cuprates, which is conventionally
modeled by a single orbital model, the multiorbital band structure is shown to
play a crucial role in the material dependence of superconductivity. In fact,
by adopting a two orbital model that considers the orbital on top of
the orbital, we can resolve a long standing puzzle of why the
single layered Hg cuprate have much higher than the La cuprate.
Interestingly, here again the apical oxygen height measured from the CuO
plane plays an important role in determining the relative energy difference
between and orbitals, thereby strongly affecting the
superconductivity.Comment: 8 pages, 7 figures, submitted as Proceedings of SNS201
First-Line Trastuzumab Plus an Aromatase Inhibitor, With or Without Pertuzumab, in Human Epidermal Growth Factor Receptor 2-Positive and Hormone Receptor-Positive Metastatic or Locally Advanced Breast Cancer (PERTAIN): A Randomized, Open-Label Phase II Trial
To assess pertuzumab plus trastuzumab and an aromatase inhibitor (AI) in patients with human epidermal growth factor receptor 2 (HER2)-positive and hormone receptor-positive metastatic/locally advanced breast cancer (MBC/LABC)
Integrative analyses identify modulators of response to neoadjuvant aromatase inhibitors in patients with early breast cancer
Introduction
Aromatase inhibitors (AIs) are a vital component of estrogen receptor positive (ER+) breast cancer treatment. De novo and acquired resistance, however, is common. The aims of this study were to relate patterns of copy number aberrations to molecular and proliferative response to AIs, to study differences in the patterns of copy number aberrations between breast cancer samples pre- and post-AI neoadjuvant therapy, and to identify putative biomarkers for resistance to neoadjuvant AI therapy using an integrative analysis approach.
Methods
Samples from 84 patients derived from two neoadjuvant AI therapy trials were subjected to copy number profiling by microarray-based comparative genomic hybridisation (aCGH, n = 84), gene expression profiling (n = 47), matched pre- and post-AI aCGH (n = 19 pairs) and Ki67-based AI-response analysis (n = 39).
Results
Integrative analysis of these datasets identified a set of nine genes that, when amplified, were associated with a poor response to AIs, and were significantly overexpressed when amplified, including CHKA, LRP5 and SAPS3. Functional validation in vitro, using cell lines with and without amplification of these genes (SUM44, MDA-MB134-VI, T47D and MCF7) and a model of acquired AI-resistance (MCF7-LTED) identified CHKA as a gene that when amplified modulates estrogen receptor (ER)-driven proliferation, ER/estrogen response element (ERE) transactivation, expression of ER-regulated genes and phosphorylation of V-AKT murine thymoma viral oncogene homolog 1 (AKT1).
Conclusions
These data provide a rationale for investigation of the role of CHKA in further models of de novo and acquired resistance to AIs, and provide proof of concept that integrative genomic analyses can identify biologically relevant modulators of AI response
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