Initial development and production of CO2 in colonies of the leaf-cutting ant Atta sexdens during the claustral foundation

Queens in the genus Atta are solely responsible for fungus cultivation and for care of herself and her offspring. Only few studies have investigated their nests in the claustral foundation and it is unknown the production rate of expelled carbon dioxide and/or of oxygen consumption in the initial colonies of leaf-cutting ants. Thus, we have studied the development of 50 initial colonies of Atta sexdens, and production of expelled carbon dioxide under laboratory conditions. The number of eggs was counted one week after nest foundation on the seventh day, the larvae counted on day 28, and the pupae between days 42 and 49. The workers emerged on the 63rd and 70th day. The CO2 concentration increased steeply in the 42nd days (20.60 ± 8.36%) and 49th days (15,37 ± 13,11 %), at 42nd days,  and subsequently returned to lower values, for example, 3.35±2.84% at week seven. The present study is the first to present CO2 emission data in initial nests, in their claustral foundation under laboratory conditions

Contextos comunicacionales adecuados e inadecuados para la inclusión de alumnos con discapacidad visual en clases de Física moderna

El presente trabajo forma parte de un estudio que procura identificar las principales barreras para la inclusión de alumnos con discapacidad visual en las clases de Física. Busca comprender cuáles son los contextos comunicacionales que favorecen y/o dificultan la participación efectiva del alumno ciego en las actividades de Física moderna. Para ello, define, a partir de las estructuras empíricas y semántico-sensoriales, el lenguaje utilizado en las actividades así como el momento y el modelo discursivo en el que esas actividades fueron utilizadas. Como resultado, identifica una intensa relación entre el empleo del lenguaje de estructura empírica audio-visual interdependiente en episodios no interactivos de autoridad, el decrecimiento de la utilización de tal estructura en los episodios interactivos, la creación de ambientes segregativos de enseñanza en el interior del aula y la frecuente utilización del lenguaje de estructura empírica táctil auditiva interdependiente en esos ambientes.This article is inserted in a wider study that seeks to understand the main inclusion barriers in Physics classes for students with visual impairment It aims to understand which communication context favorsor impedes the visually impaired student participation to the impairment visual student's real participation in Modern Physics activities. The research defines, from the empirical-sensory and semantics structures, the languages used in the activities, as well as, the moment and the speech pattern in which those languages have been used. As a result, this study identifies a strong relation between the uses of the interdependent empirical structure audio-visual language in the non-interactive episodes of authority; a decrease of this structure use in the interactive episodes; the creation of education segregation environments within the clasroom and the frequent use of empirical tactile-hearing interdependent language structure in these environments. Moreover, the concept of «special educational need» is discussed and its inadequate use is analyzed. Suggestions are given for its correct use of «special educational need,» its inadequate use, giving suggestions for its correct use

Future high school teachers' difficulties and alternatives found to planning electromagnetism activities designed for visual handicapped students

We report here partial outcomes of a study aimed to verify future High School teachers' performance when, during the development of a called "Teaching Practice" undergraduate course, were asked to plan, elaborate and teach, in classroom situations, electromagnetism topics to a students class which included visual handicapped pupils. Data analyzed show that the main difficulties presented by the future Physics High School teachers are related to the approach to know physics phenomena as dependent of vision and to break with some elements of the traditional pedagogy. By other hand, as alternatives, future teachers showed creativity in order to surpass passive aptitudes related to this educational problem, working out methodological strategies deprived of the relation knowing/seeing, as well as, the work with orality in a physics education context

Resistance of sugarcane commercials cultivars to causal agent of ratoon stunting disease

O raquitismo-da-soqueira (RSD), causado pela bactéria Leifsonia xyli subsp. xyli, é uma das mais importantes doenças da cana-de-açúcar nas regiões produtoras do mundo. O presente trabalho teve como objetivo avaliar o grau de resistência de 10 variedades comerciais RB de cana-de-açúcar mais a variedade CB 49-260, a qual foi incluída como padrão suscetível. O trabalho visou avaliar os danos amostrados em campo pelo peso das parcelas em função da relação entre a produtividade de parcelas inoculadas e não inoculadas artificialmente com a bactéria. Os resultados mostraram que as variedades RB 72 454, RB 83 5486, RB 86 7515, RB 92 5211, RB 92 5268, RB 92 5345, RB 92 8064 e a variedade padrão CB 49-260 comportaram-se como variedades suscetíveis. A variedade RB 85 5156 comportou-se como de resistência intermediária e apenas as variedades RB 85 5453 e RB 85 5536 comportaram-se como tolerantes.Ratoon stunting disease (RSD) caused by bacteria Leifsonia xyli subsp. xyli is one of the most economically important disease of sugarcane worldwide. The present survey had objective to evaluate the resistance of 10 RB commercial cultivars of sugarcane including CB 49-260 as a susceptible standard. The study evaluated the correlating the damages presented for overhauls productivity of inoculate and non inoculate parcels with the bacteria. The results showed that varieties RB 72 454, RB 83 5486, RB 86 7515, RB 92 8064, RB 92 5211, RB 92 5345 and RB 92 5268 were susceptible. RB 85 5156 had a intermediary resistance and varieties RB 85 5453 and RB 85 5536 both showed tolerant behavior

Idiopathic sudden sensorineural hearing loss: etiopathogenic aspects

SummarySeveral factors have been postulated to elicit the etiology of idiopathic sudden sensorineural hearing loss. Through a bibliographic review, we made a critical analysis of the different etiopathogenic aspects of its clinical manifestation. The most recent studies concerning the possible causes of sudden hearing loss suggest vascular disorders, rupture of the inner ear membrane and autoimmune diseases; however, viral infections have received a great deal of attention in recent years. Little is known about the mechanism of sudden hearing loss. Viruses can cause sudden hearing loss in an acute infection, however the latent form, and its possible reactivation have also been considered as explanations of the cochlear injury mechanism. Even though hearing loss can be explained by a blood viscosity change, experimental and clinical studies do not show any evidence of labyrinthine fibrosis and new bone formation, or labyrinthine membrane breaks. These findings are not in agreement with vascular and rupture membrane factors, respectively. The eventual presence of antibodies against the inner ear suggests that sudden hearing loss pathogenesis may be of autoimmune nature, but the difficulty in establishing the correlation of its morphological and clinical aspects to the hearing loss also do not help to support this statement. Sudden hearing loss is still a controversial and obscure subject in several aspects

Detección de información relevante en funciones de modo intrínseco

The empirical mode decomposition (EMD) decomposes a local and adaptive time series into a finite set of intrinsic mode functions (IMF), AM-FM signals that allow to represent a non-linear and non-stationary model with the advantage of not losing the underlying meaning. This study examines time series of sEMG measurements for a case study of healthy individuals with carpal tunnel syndrome. Due to the amount of multiple levels of detail, all around a central frequency and evoked by the number of IMFs obtained through EMD, the informational contribution of each at the intermodal and interindividual level is studied through Shannon entropy to establish a general framework of spectral study given Hilbert Huang's (HHT) transformation to remarkable degrees of information. The results show that the latest IMFs have more disordered states even when they engage in apparently regular behavior, agglomerate more time-frequency information, and in the same way, concentrate more differentiable characteristics for a process of individualization of patterns.Este estudio explora la descomposición empírica de modos (EMD), técnica local y adaptativa que descompone una serie de tiempo en un conjunto finito de funciones de modo intrínseco (IMF), señales con amplitud y frecuencia variable que permiten representar un modelo no lineal y no estacionario con la ventaja de no perder el significado físico subyacente. Para el caso se examinan series de tiempo provenientes de mediciones sEMG de un estudio de caso de individuos sanos y con síndrome de túnel del carpo. Debida la cantidad de múltiples niveles de detalle, todos alrededor de una frecuencia central y evocados a la cantidad de IMFs obtenidas a través de la EMD, se estudia el aporte informativo de cada uno a nivel intermodal e interindividual a través de la entropía de Shannon, de manera que se logre establecer un marco general que propicie un enfoque al estudio espectral dada la transformada de Hilbert Huang (HHT) a grados de información destacables. Los resultados permiten evidenciar que sobre las últimas componentes IMF se logran los estados más potenciales al desorden, aun cuando comprometen un comportamiento más regular, aglomeran más información tiempo-frecuencia y del mismo modo, concentran las características más diferenciables para un proceso de individualización de patrones

Los toros : reseña gráfica de la fiesta española

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 201

Aplicación lógica difusa en valoración financiera de marcas

Resumen: El uso de la lógica difusa en la valoración tiene como objetivo proporcionar las bases del razonamiento aproximado, que utiliza las premisas subjetivas como instrumento para calcular el valor de las marcas que es muy subjetivo por su componente intangible. La valoración de marcas es un ejemplo de aplicación en el que se hace necesario introducir esquemas matemáticos flexibles ofrecidos por la lógica difusa, de esa forma es más real el determinar el grado de ajuste de determinados factores considerados como de éxito para el valor de la empresa. En situaciones en la que la no puede darse un valor exacto para los parámetros del problema, su información no es cuantificable e incompleta o no puede obtenerse se puede usar la teoría de conjuntos difusos. La lógica difusa no exige valores exactos, soporta valoraciones subjetivas e incluso valoraciones lingüísticas para los parámetros del problema y las incorpora apropiadamente a modelos matemáticos complejosAbstract: The use of fuzzy logic in the assessment is intended to provide the basis of approximate reasoning, subjective assumptions used as a tool to calculate the value of the brands that is very subjective by its intangible component. The brand valuation is an example application in which it is necessary to introduce flexible mathematical schemes offered by fuzzy logic, in that way is more real to determine the degree of fit of certain success factors considered for the value of the company. In situations in which there can be no exact value for the parameters of the problem, your information is not quantifiable and incomplete or cannot be obtained using fuzzy set theory. Fuzzy logic does not require exact values, supports and even subjective assessments linguistic evaluations for the parameters of the problem and properly incorporating complex mathematical modelsMaestrí