Habilidades relacionadas con la comprensión lectora en lectores iniciales que crecen en contextos de pobreza / Skills related to reading comprehension in early readers growing up in poverty contexts

Resumen El presente trabajo se propuso analizar la contribución de la comprensión de lenguaje oral y la velocidad y la precisión en la lectura de palabras en la comprensión lectora en lectores iniciales del español que crecen en contextos de pobreza urbana. Para ello, se evaluó a 31 niños de 3er grado que crecían en barrios socialmente vulnerables de la provincia de Buenos Aires, Argentina, mediante pruebas de comprensión lectora, precisión y velocidad lectora, vocabulario y procesamiento morfosintáctico. Los resultados de la muestra total indican que la medida de comprensión lectora se asoció a las medidas de vocabulario, procesamiento de lenguaje oral, y velocidad y precisión en la lectura. En contraposición a resultados obtenidos en otras lenguas de ortografía transparente, el análisis de una regresión indicó que la comprensión lectora estuvo mayormente explicada por la medida de precisión y no de velocidad en la lectura de palabras. A fin de enriquecer el análisis de los datos, a partir de los resultados en la prueba de comprensión de textos se conformaron dos grupos de niños con diferente nivel de comprensión lectora: un grupo de niños con un nivel de comprensión lectora cercano a la media obtenida (21 sujetos) y un grupo de niños cuyo desempeño se ubicó en un desvío por debajo de la media en la medida de comprensión (10 sujetos). Los resultados de una prueba de comparación de medias mostraron que entre grupos de niños con diferente nivel de comprensión lectora las habilidades que se diferenciaron fueron las relacionadas al procesamiento morfosintáctico.

Abstract The present study aims to analyze the contribution of oral language and reading comprehension skills in early readers of Spanish who grow up in poverty context in Buenos Aires, Argentina. For this, reading comprehension, reading accuracy, reading fluency, vocabulary and morphosyntax processing were tested in 31 3rd graders. Full sample data analysis show that reading comprehension measures was associated with vocabulary, oral language processing, reading speed and accuracy. In contrast to results obtained in other languages with transparent orthographies, regression analysis shows that reading comprehension was mainly explained by reading accuracy and not by reading speed. In order to improve the data analysis, two groups of children with different levels of reading comprehension were selected: one group (21 children) whose level of comprehension was near to the average obtained and one group of children (10 subjects) with lower reading comprehension level. The results of a mean comparison test showed that in groups of children with different levels of reading comprehension, the skills that differed were those related to morphosyntactic processing.

The injectable resin composite restorative technique: A case report.

OBJECTIVE: To describe the use of the injectable resin composite restorative technique with a flowable resin material, in a clinical case with esthetic problems associated with irregular tooth anatomies, allied with a finishing, and polishing protocol due to staining after 1 year of use. CLINICAL CONSIDERATIONS: The presented case report helped to achieve an immediate highly esthetic restoration with appropriate width proportions based on a previous wax-up. After 1 year of use, restorations presented staining; therefore, finishing and polishing procedures were required to re-achieve acceptable esthetic results and thus increase restoration's survival. CONCLUSIONS: The use of the presented technique allowed to obtain a simple and predictable workflow; however, care must be taken on the follow up of the restorations due to intrinsic characteristics of the flowable resin material. CLINICAL SIGNIFICANCE: The use of the presented injectable technique helped on obtaining a precise anatomy replicating a diagnostic wax-up, thus improving marginal precision and achieving a highly esthetic and functional immediate outcome, with an easy workflow when appropriately planned and executed. However, it also presented low color stability after 1 year of use only, thus, requiring attention from clinicians in regard to its maintenance over time.

Interfaces Cerebro-Computadora: Conceptualización, Retos de Rediseño e Impacto Social / Brain Computer-Interfaces: Conceptualization, Redesign Challenges and Social Impact

Resumen Las Interfaces Cerebro-Computadora (ICCs) son sistemas que miden la actividad del Sistema Nervioso Central y la convierten en salidas que reemplazan, restauran, aumentan, suplementan o mejoran las salidas naturales de dicho sistema y, por lo tanto, cambian las interacciones en curso entre el ser humano y su ambiente interno o externo. Sin embargo, a más de medio siglo de ser investigadas en condiciones de laboratorio, las ICC no han podido ser trasladadas al mundo real. En el presente artículo de revisión se busca: (1) comprender a fondo la estructura de una ICC y los tipos de sistema, (2) analizar el reto que tiene la comunidad científica para mejorar la interacción entre usuario y sistema desde la perspectiva de la ingeniería de factores humanos y (3) describir la aplicación de este tipo de tecnología de asistencia en desarrollo en la sociedad mexicana. El futuro de estas ICC y la eficiencia con que logren el objetivo para el que fueron diseñadas parece depender, más que nunca, de factores relacionados a la percepción subjetiva del usuario, su adaptación al manejo de las ICC y el proceso de internalizarlas como propias en su espacio personal y su psique.

Abstract Brain-Computer Interfaces (BCIs) record the neural activity of the Central Nervous System, and then, produce outputs that replace, restore, increase, supplement or improve the natural outputs of such system. Therefore, the interaction between the human beings and their internal or external environment is transformed. However, over a century being investigated under laboratory conditions, BCIs have not been able to be transferred to the real world. This review aims to: (1) thoroughly understand the structure of a BCI and the system types, (2) analyze the challenge that the scientific community is facing to improve the interaction between user and system from the perspective of the engineering of human factors; and (3) describe the application of this type of assistive technology under development in the Mexican Society. The future of this technology and its effectiveness seem to depend more than ever on factors related to the user subjective perception, and the user adaptation to the system.

Electroless controllable growth of ZnO films and their morphology-dependent antimicrobial properties.

An electroless deposition process was used to synthesize with a controlled morphology, polycrystalline ZnO on glass substrates as antimicrobial coatings. The influence of deposition temperature (Tdep) on the physicochemical and antimicrobial properties of the ZnO films was analyzed. The results indicated that a change in deposition temperature greatly affected the morphology and the degree of crystallinity of the films. Scanning electron microscope images show that the film surface is porous at a deposition temperature of 40 and 50 °C, whereas hexagonal-plate shaped morphology predominated at 60 °C and finally at 70 and 80 °C the films consisted of rod-like particles. The films showed good transparency in the visible region. All ZnO films presented notable antimicrobial activity against the gram-negative bacteria Escherichia coli (E. coli) and the gram-positive Staphylococcus aureus (S. aureus). It was found that the antimicrobial efficiency is strongly dependent on morphology and structural properties. The best antimicrobial performance was recorded for the films consisting of rod-like morphology with a high degree of crystallinity. The procedure used in this investigation is strongly recommended for the development of functional surfaces.

Antibiofilm effect of supramolecularly templated mesoporous silica coatings.

Bacteria attached to solid surfaces and encased in a self-synthesized matrix, so-called biofilms, are highly difficult to eradicate and present negative impact on industry and human health. The ability of supramolecularly templated mesoporous silica coatings to inhibit biofilm formation in Pseudomonas aeruginosa is shown here. Assays employing submerged and air-liquid interface biofilms demonstrated that mesoporous coatings with tuned pore size significantly reduce the number of attached bacteria and matrix production. Given its versatility, scalability, robustness and low cost, our proposal is attractive for the production of transparent, inert and permanent antibiofilm coatings that could be applied on multiple surfaces.

Structure, Electronic Properties, and Electrochemical Behavior of a Boron-Doped Diamond/Quartz Optically Transparent Electrode.

The morphology, microstructure, chemistry, electronic properties, and electrochemical behavior of a boron-doped nanocrystalline diamond (BDD) thin film grown on quartz were evaluated. Diamond optically transparent electrodes (OTEs) are useful for transmission spectroelectrochemical measurements, offering excellent stability during anodic and cathodic polarization and exposure to a variety of chemical environments. We report on the characterization of a BDD OTE by atomic force microscopy, optical spectroscopy, Raman spectroscopic mapping, alternating-current Hall effect measurements, X-ray photoelectron spectroscopy, and electrochemical methods. The results reported herein provide the first comprehensive study of the relationship between the physical and chemical structure and electronic properties of a diamond OTE and the electrode's electrochemical activity.

Desarrollo de la conciencia sintáctica y fonológica en niños chilenos: un estudio transversal / Development of syntactic and phonological awareness in Chilean children: a cross-sectional study

El desarrollo de la conciencia sintáctica ha sido escasamente investigado en una ortografía transparente como la del español. Situación totalmente contraria es la que ha experimentado la conciencia fonológica, cuyo desarrollo y rol en la adquisición lectora han recibido mucha más atención tanto en lenguas transparentes como en opacas. Investigaciones en inglés y en francés han demostrado que las habilidades metasintácticas siguen desarrollándose después de comenzada la alfabetización y que incluso a los 11 o 14 años aún no ha culminado este desarrollo. El propósito del presente estudio es describir y comparar el desarrollo evolutivo de la conciencia sintáctica y conciencia fonológica en niños chilenos del periodo básico. Para ello, se seleccionó una muestra de 234 sujetos, pertenecientes a colegios públicos y privados, quienes realizaron individualmente una tarea de conciencia sintáctica y otra de conciencia fonémica. Los resultados en español confirman los hallazgos obtenidos en lenguas opacas, puesto que muestran que el desarrollo de ambas habilidades metalingüísticas continúa evolucionando durante el periodo básico.

The development of syntactic awareness has still not been widely investigated in a transparent orthography, such as Spanish. On the other hand, the increase of phonological awareness and its contribution to reading acquisition has received much more attention, both in opaque and transparent languages. Studies with English and French speaking children have demonstrated that syntactic awareness continues developing after reading instruction begins, and that even at the age of 11 or 14 it is not completely developed. The aim of this study was to describe and compare the development of syntactic awareness and phonological awareness in Chilean children from elementary grades. A sample of 234 Chilean children participated in the study, and they were assessed individually in syntactic and phonological awareness tasks. Results in Spanish confirmed similar findings found in opaque languages, as it was shown that both meta-linguistic abilities are still being developed at the school levels evaluated in this study.

Anglocentrismo en los modelos de adquisición lectora?: un estudio en una lengua de ortografía transparente / Anglocentrism in reading acquisition models?: a study in a language with transparent orthography

En el estudio se analiza si las revisiones propuestas por Share (2008) a los modelos anglosajones de adquisición lectora pueden dar cuenta de estos procesos en español, una lengua de ortografía transparente. Share cuestionó la noción de aprendizaje en etapas, la importancia otorgada a la precisión lectora por sobre la velocidad y el peso atribuido al procesamiento fonológico. Se evaluó a un grupo de 52 niños de nivel socioeconómico bajo mediante pruebas de conocimiento de correspondencias, conciencia fonológica, denominación rápida y lectura de palabras a principios y mediados de primer grado y mediante una prueba de lectura de palabras y pseudopalabras hacia el final de primer y segundo grado. Los resultados mostraron la irrelevancia de las tempranas estrategias no fonológicas de lectura, un alto nivel de precisión lectora a fin de segundo grado acompañado de importantes diferencias en la velocidad de lectura, habilidad que estuvo estrechamente ligada a la denominación rápida. Estos resultados dan apoyo al modelo de adquisición lectora propuesto por Share (2008). Éste se caracteriza por un proceso continuo de gradual incremento de las habilidades de recodificación fonológica, con un temprano logro de la precisión y un peso importante de las diferencias individuales en el logro de la velocidad lectora.

The present research aimed to check Share’s (2008) thesis about conventional reading acquisition models in a group of Argentinean children. This author proposes that reading models developed for English need to be reviewed when children are learning to read in a language with transparent orthography. Share questions the idea of learning proceeds in stages, the importance given to reading accuracy over speed and the relevance of phonological processing. A group of 52 children from low-income families were tested on letter knowledge, phonological awareness, rapid naming and reading of frequent words at the beginning and the middle of first grade. Additionally, children’s word and pseudo-word reading skills were tested at the end of first and second grade. Results showed that most children never resorted to non-phonological strategies as it is usually done by their equals in English. By the end of second grade the group had reached a high level of accuracy in reading, but important differences were found in reading speed. These results support Share’s (2008) proposal since reading acquisition did not develop in a series of stages but could be described as a continuous process in which children gradually increase their phonological recoding abilities and achieve accuracy early on. Therefore individual differences in reading speed become a critical aspect of reading.

Comportamiento de la cirugía facorrefractiva en la alta miopía / Behaviour of the phacorefractive surgery in high myopia

OBJETIVO: Determinar la efectividad de la cirugía facorrefractiva en pacientes miopes altos a partir de los resultados refractivos y la incidencia de complicaciones en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer" en un período de 5 años. MÉTODOS: Se realizó un estudio descriptivo, retrospectivo de un universo de 137 ojos de 73 pacientes con diagnóstico de alta miopía que fueron sometidos a cirugía de extracción del cristalino transparente, mediante técnica de Facoemulsificación, en el Centro de Microcirugía del Instituto Cubano de Oftalmología "Ramón Pando Ferrer" en el periodo de tiempo comprendido de enero de 2003 hasta enero de 2008. Se estudiaron 80 ojos de pacientes que cumplían con los criterios de inclusión. Se evaluaron las siguientes variables: edad, sexo, mejor agudeza visual sin corrección preoperatoria y posoperatoria, mejor agudeza visual corregida preoperatoria y posoperatoria, componente esférico, astigmatismo inducido y complicaciones transoperatorias y posoperatorias. RESULTADOS: El rango de edad predominante estuvo entre 46 y 55 años representando un 75 por ciento del total. La agudeza visual sin corrección y mejor corregida mejoró significativamente en más del 90 por ciento de los pacientes tras la cirugía. No se indujo astigmatismo en el 77,5 por ciento de los casos. La incidencia de complicaciones fue baja para un 10 por ciento. El desprendimiento de retina solo se presentó en un 2,5 por ciento. CONCLUSIONES: La cirugía facorrefractiva del cristalino, a pesar de ser aún un tema controversial, es una opción efectiva para el tratamiento de las altas miopías con muy buenos resultados visuales, una predictibilidad y estabilidad excelente, así como una baja incidencia de complicaciones.

OBJECTIVE: To determine the effectiveness of phacorefractive surgery in high myopic patients based on the refractive results and the incidence of complications at "Ramón Pando Ferrer" Cuban Institute of Ophthalmology in a five-year period. METHODS: A retrospective and descriptive study of a universe of 137 eyes from 73 patients diagnosed with high myopia and subjected to transparent crystalline extraction surgery using phacoemulsification technique was carried out at the Center of Microsurgery in "Ramón Pando Ferrer" Cuban Institute of Ophthalmology from January 2003 to January 2008. Eighty eyes of patients who met the inclusion criteria were studied. The following variables were evaluated: age, sex, better visual acuity without preoperative and postoperative correction, best corrected visual acuity before and after surgery, spheral component, induced astigmatism and transoperative and postoperative complications. RESULTS: The predominant age range was 46-55 years accounting for 75 percent of the total number. The visual acuity without correction and best corrected acuity improved significantly in over 90 percent of the patients after the surgery. Induced astigmatism was not observed in 77.5 percent of cases. The incidence of complications was low in 10 percent. Retinal detachment was present in 2,5 percent of patients. CONCLUSIONS: Despite the controversial nature of this topic, the phacorefractive surgery of the crystalline is an effective alternative for the treatment of high myopias with very good visual results, excellent predictability and stability and low incidence of complications.