Conferencias científicas de las alumnas de la Escuela Normal para Profesoras en el período del 6 de Junio al 25 de Julio de 1903

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Conferencias cientificas de las alumnas de la Escuela Normal para Profesoras en el periodo del 6 de Junio al 25 de Julio de 1891

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Conferencias científicas de las alumnas de la Escuela Normal para profesoras en el periodo del 3 de junio al 29 de julio de 1893

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Conferencias científicas a los niños

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La superdotación : concepto y actitudes de los estudiantes de psicología, ciencias de la educación y magisterio.

Recoger de forma sistemática y precisa las actitudes, conocimientos, intereses y relación en general que los alumnos de psicología, pedagogía y magisterio como futuros profesionales mantienen con respecto a la superdotación. Las hipótesis de trabajo son: H1. El conocimiento que los alumnos de psicología, pedagogía y magisterio tienen sobre el tema de la superdotación es escaso. SH 1.1. Los currícula incluyen poca información sobre superdotación. SH 1.2. Reciben menos información sobre superdotados que sobre deficientes. SH 1.3. Carecen de una definición clara de superdotación. SH 1.4. La información y los conocimientos respecto al tema varían según la especialidad. H2. En la muestra seleccionada existe una escasa relación con el tema de la superdotación. SH 2.1. La relación con el tema varía según la especialidad. SH 2.2. La relación con la deficiencia mental es mayor que con la superdotación. H3. Las actitudes de los alumnos seleccionados hacia el tema de la superdotación son poco favorables. SH 3.1. Las actitudes sobre deficiencia mental son más favorables que aquellas referidas a la superdotación. SH 3.2. Las actitudes varían según la especialidad cursada por los sujetos de la muestra. H4. Los alumnos de psicología, pedagogía y magisterio desconocen cuáles son los objetivos educativos propios del trabajo con superdotados. SH 4.1. La muestra no diferencia los objetivos educativos para el trabajo con niños deficientes, normales o superdotados. SH 4.2. La selección de los objetivos varía en función de la especialidad cursada. 235 estudiantes seleccionados entre los alumnos matriculados en las cuatro especialidades de tercero de magisterio (76), en segundo (16) y quinto (11) de pedagogía, y en tercero (66) y quinto (66) de psicología, durante los cursos 88-89 y 89-90. En la parte teórica se presentan y describen los modelos más relevantes sobre la naturaleza y medición de la inteligencia y, a su vez, las principales investigaciones realizadas sobre el tema de la superdotación. Seguidamente se analizan las distintas definiciones existentes sobre la superdotación, recopilando las características más importantes de la misma. Para concluir se recogen los trabajos más destacados sobre opiniones, creencias y actitudes de distintos profesionales hacia los superdotados. La parte experimental queda claramente reflejada en el resto de apartados. Cuestionario compuesto por cinco partes diferentes: 1. Rejilla: dos, una para la superdotación y otra para deficiencia mental. Con ellas se podrá evaluar la importancia de la superdotación en función de las especialidades y sus currícula correspondientes. 2. Definiciones; para controlar el concepto que se tiene de la superdotación. 3. Cuestionario: dos, uno para superdotación y otro para deficiencia mental; valora las distintas opiniones, relación y conocimientos sobre el tema. 4. Actitudes: escala de Klaus K. Urban sobre actitudes hacia la educación del superdotado. Valora diferentes aspectos relacionados con el tema, como por ejemplo, la educación especial, la integración, etc. 5. Objetivos educativos. Se partió de una escala creada por Klaus K. Urban. Valora qué objetivos son relevantes para el trabajo con superdotados. Análisis descriptivo para rejilla, cuestionario, actitudes y objetivos educativos, lo cual da una primera aproximación a la agrupación de resultados a través de proporciones, separadamente para cada grupo. Contraste entre grupos con el método x2. Análisis factorial para conocer los componentes subyacentes principales con elección de factores eigen value superior a uno y rotación ortogonal VARIMAX. Se utiliza el Stadistical Package for Social Sciencies o SPSS. Análisis de contenido para el apartado de definición: ideas básicas de lo que es un superdotado. 1. Rejilla: la superdotación recibe una escasa atención en los estudios de psicología, pedagogía y magisterio de nuestra universidad. Los pedagogos apenas trabajan el tema. Se constatan diferencias de tiempo, amplitud y profundidad entre deficiencias y superdotación. Se confirma SH 1.1., SH 1.2. y SH 1.4. 2. Definición: suelen centrarse en conceptos psicométricos o características aptitudinales muy difusas confirmándose así la SH 1.3. 3. Cuestionario: Los alumnos no poseen libros sobre la superdotación, la asistencia a cursos, seminarios, conferencias, etc., sobre el tema es casi nula, nadie manifiesta conocer a algún profesional que la trabaje exceptuando el propio ámbito universitario. La cosa cambia bastante al tratar la deficiencia mental: la mayoría posee documentación y conoce a alguien que trabaja el tema. La falta de información sobre superdotados repercute en un menor interés por el tema. Muchos opinan que para trabajar con ellos necesitan mayor preparación. Al poseer mucha información sobre deficientes mentales se valora el tema como muy interesante e importante para su futuro profesional. Se confirma la segunda hipótesis, SH 2.1. y SH 2.2. 4. Actitudes: la superdotación necesita atención especial e integración en centros normales pero hay dispersión acerca de si la identificación temprana es o no perjudicial para su desarrollo y sobre la conveniencia de crear colegios especiales para estos niños. La deficiencia mental debe identificarse tempranamente; educación especial dirigida a sus necesidades, capacidades e intereses, integración aconsejable. La tercera hipótesis debería matizarse. Las actitudes hacia la superdotación son heterogéneas y poco claras aunque mayoritariamente favorables. Se confirma SH 3.1. pero no SH 3.2. 5. Objetivos educativos: se atribuyen los mismos a los grupos normales y superdotados pero no a los deficientes. Se confirma H4 y SH 4.1. pero no SH 4.2. Falta una teoría general que abarque los conocimientos que se tienen sobre el tema de la superdotación. Se detectan amplias perspectivas de futuro, cada vez son más numerosos los libros, revistas especializadas, congresos e instituciones dedicadas al tema. Es necesario preparar a los alumnos porque la demanda social de especialistas en este campo ya ha empezado y porque la buena información es el primer paso para conseguir mayor entendimiento, aceptación e interés hacia el tema.

La historia de la educación de las mujeres en España : líneas actuales de investigación.

Resumen basado en el del autor. Resumen en castellano e inglés. Notas a pie de página. Este artículo se incluye en el monográfico 'Temas actuales de enseñanza'

MCAO for Extremely Large Telescopes: the cases of LBT and E-ELT

Several MCAO systems are under study to improve the angular resolution of the current and of the future generation large ground-based telescopes (diameters in the 8-40 m range). The subject of this PhD Thesis is embedded in this context. Two MCAO systems, in dierent realization phases, are addressed in this Thesis: NIRVANA, the 'double' MCAO system designed for one of the interferometric instruments of LBT, is in the integration and testing phase; MAORY, the future E-ELT MCAO module, is under preliminary study. These two systems takle the sky coverage problem in two dierent ways. The layer oriented approach of NIRVANA, coupled with multi-pyramids wavefront sensors, takes advantage of the optical co-addition of the signal coming from up to 12 NGS in a annular 2' to 6' technical FoV and up to 8 in the central 2' FoV. Summing the light coming from many natural sources permits to increase the limiting magnitude of the single NGS and to improve considerably the sky coverage. One of the two Wavefront Sensors for the mid- high altitude atmosphere analysis has been integrated and tested as a stand- alone unit in the laboratory at INAF-Osservatorio Astronomico di Bologna and afterwards delivered to the MPIA laboratories in Heidelberg, where was integrated and aligned to the post-focal optical relay of one LINC-NIRVANA arm. A number of tests were performed in order to characterize and optimize the system functionalities and performance. A report about this work is presented in Chapter 2. In the MAORY case, to ensure correction uniformity and sky coverage, the LGS-based approach is the current baseline. However, since the Sodium layer is approximately 10 km thick, the articial reference source looks elongated, especially when observed from the edge of a large aperture. On a 30-40 m class telescope, for instance, the maximum elongation varies between few arcsec and 10 arcsec, depending on the actual telescope diameter, on the Sodium layer properties and on the laser launcher position. The centroiding error in a Shack-Hartmann WFS increases proportionally to the elongation (in a photon noise dominated regime), strongly limiting the performance. To compensate for this effect a straightforward solution is to increase the laser power, i.e. to increase the number of detected photons per subaperture. The scope of Chapter 3 is twofold: an analysis of the performance of three dierent algorithms (Weighted Center of Gravity, Correlation and Quad-cell) for the instantaneous LGS image position measurement in presence of elongated spots and the determination of the required number of photons to achieve a certain average wavefront error over the telescope aperture. An alternative optical solution to the spot elongation problem is proposed in Section 3.4. Starting from the considerations presented in Chapter 3, a first order analysis of the LGS WFS for MAORY (number of subapertures, number of detected photons per subaperture, RON, focal plane sampling, subaperture FoV) is the subject of Chapter 4. An LGS WFS laboratory prototype was designed to reproduce the relevant aspects of an LGS SH WFS for the E-ELT and to evaluate the performance of different centroid algorithms in presence of elongated spots as investigated numerically and analytically in Chapter 3. This prototype permits to simulate realistic Sodium proles. A full testing plan for the prototype is set in Chapter 4.

Multipath Reflectivity Estimation in Urban Environments for Synthetic Aperture Radar Images

Synthetic Aperture Radar (SAR) images a target region reflectivity function in the multi-dimensional spatial domain of range and cross-range. SAR synthesizes a large aperture radar in order to achieve a finer azimuth resolution than the one provided by any on-board real antenna. Conventional SAR techniques assume a single reflection of transmitted waveforms from targets. Nevertheless, today¿s new scenes force SAR systems to work in urban environments. Consequently, multiple-bounce returns are added to directscatter echoes. We refer to these as ghost images, since they obscure true target image and lead to poor resolution. By analyzing the quadratic phase error (QPE), this paper demonstrates that Earth¿s curvature influences the defocusing degree of multipath returns. In addition to the QPE, other parameters such as integrated sidelobe ratio (ISLR), peak sidelobe ratio (PSLR), contrast (C) and entropy (E) provide us with the tools to identify direct-scatter echoes in images containing undesired returns coming from multipath.

Lick Observatory bulletins

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Advances in preservation of fruits and vegetables with bioactive coatings

Bioactive compounds are a large group of compounds (antimicrobials, antioxidants, nutrients, etc.), but its use in edible fi lms and coatings for application on fruits and vegetables has been very important because nowadays the consumers demand fruits and vegetables that are fresh, healthy, high quality and easy to prepare. A number of investigations have shown that the use of additives in edible fi lms and coatings improve its functionability and provide compounds for human health. However, it is necessary to continue research that can generate specifi c or tailor-made edible fi lms and coatings for each product with the best characteristics for preservation. In this review we present and analyze the concepts, progress and perspectives in the design and application of edible fi lms and coatings for fruits and vegetables in order to defi ne the challenges and opportunities that this topic of study in the fi eld of science, technology and food engineering.

Estudos experimentais sôbre a origem do milho

1) It may seem rather strange that, in spite of the efforts of a considerable number of scientists, the problem of the origin of indian corn or maize still has remained an open question. There are no fossil remains or archaeological relics except those which are quite identical with types still existing. (Fig. 1). The main difficulty in finding the wild ancestor- which may still exist - results from the fact that it has been somewhat difficult to decide what it should be like and also where to look for it. 2) There is no need to discuss the literature since an excellent review has recently been published by MANGELSDORF and REEVES (1939). It may be sufficient to state that there are basically two hypotheses, that of ST. HILAIRE (1829) who considered Brazilian pod corn as the nearest relative of wild corn still existing, and that of ASCHERSON (1875) who considered Euchlaena from Central America as the wild ancestor of corn. Later hypotheses represent or variants of these two hypotheses or of other concepts, howewer generally with neither disproving their predecessors nor showing why the new hypotheses were better than the older ones. Since nearly all possible combinations of ideas have thus been put forward, it har- dly seems possible to find something theoretically new, while it is essential first to produce new facts. 3) The studies about the origin of maize received a new impulse from MANGELSDORF and REEVES'S experimental work on both Zea-Tripsacum and Zea-Euchlaena hybrids. Independently I started experiments in 1937 with the hope that new results might be obtained when using South American material. Having lost priority in some respects I decided to withold publication untill now, when I can put forward more concise ideas about the origin of maize, based on a new experimental reconstruction of the "wild type". 4) The two main aspects of MANGELSDORF and REEVES hypothesis are discussed. We agree with the authors that ST. HILAIRE's theory is probably correct in so far as the tunicata gene is a wild type relic gene, but cannot accept the reconstruction of wild corn as a homozygous pod corn with a hermaphroditic tassel. As shown experimentally (Fig. 2-3) these tassels have their central spike transformed into a terminal, many rowed ear with a flexible rachis, while possessing at the same time the lateral ear. Thus no explanation is given of the origin of the corn ear, which is the main feature of cultivated corn (BRIEGER, 1943). The second part of the hypothesis referring to the origin of Euchlaena from corn, inverting thus ASCHERSON's theory, cannot be accepted for several reasons, stated in some detail. The data at hand justify only the conclusion that both genera, Euchlaena and Zea, are related, and there is as little proof for considering the former as ancestor of the latter as there is for the new inverse theory. 5) The analysis of indigenous corn, which will be published in detail by BRIEGER and CUTLER, showed several very primitive characters, but no type was found which was in all characters sufficiently primitive. A genetical analysis of Paulista Pod Corn showed that it contains the same gene as other tunicates, in the IV chromosome, the segregation being complicated by a new gametophyte factor Ga3. The full results of this analysis shall be published elsewhere. (BRIEGER). Selection experiments with Paulista Pod Corn showed that no approximation to a wild ancestor may be obtained when limiting the studies to pure corn. Thus it seemed necessary to substitute "domesticated" by "wild type" modifiers, and the only means for achieving this substitution are hybridizations with Euchlaena. These hybrids have now been analysed init fourth generation, including backcrosses, and, again, the full data will be published elsewhere, by BRIEGER and ADDISON. In one present publication three forms obtained will be described only, which represent an approximation to wild type corn. 6) Before entering howewer into detail, some arguments against ST. HILAIRE's theory must be mentioned. The premendelian argument, referring to the instability of this character, is explained by the fact that all fertile pod corn plants are heterozygous for the dominant Tu factor. But the sterility of the homozygous TuTu, which phenotypically cannot be identified, is still unexplained. The most important argument against the acceptance of the Tunicata faetor as wild type relic gene was removed recently by CUTLER (not yet published) who showed that this type has been preserved for centuries by the Bolivian indians as a mystical "medicine". 7) The main botanical requirements for transforming the corn ear into a wild type structure are stated, and alternative solutions given. One series of these characters are found in Tripsacum and Euchlaena : 2 rows on opposite sides of the rachis, protection of the grains by scales, fragility of the rachis. There remains the other alternative : 4 rows, possibly forming double rows of female and male spikelets, protection of kernels by their glumes, separation of grains at their base from the cob which is thin and flexible. 8) Three successive stages in the reconstruction of wild corn, obtained experimentally, are discussed and illustrated, all characterized by the presence of the Tu gene. a) The structure of the Fl hybrids has already been described in 1943. The main features of the Tunicata hybrids (Fig. -8), when compared with non-tunicate hybrids (Fig. 5-6), consist in the absence of scaly protections, the fragility of the rachis and finally the differentiation of the double rows into one male and one female spikelet. As has been pointed out, these characters represent new phenotypic effects of the tunicate factor which do not appear in the presence of pure maize modifiers. b) The next step was observed among the first backcross to teosinte (Fig. 9). As shown in the photography, Fig. 9D, the features are essencially those of the Fl plants, except that the rachis is more teosinte like, with longer internodes, irregular four-row-arrangement and a complete fragility on the nodes. c) In the next generation a completely new type appeared (Fig. 10) which resembles neither corn nor teosinte, mainly in consequence of one character: the rachis is thin and flexible and not fragile, while the grains have an abscission layer at the base, The medium sized, pointed, brownish and hard granis are protected by their well developed corneous glumes. This last form may not yet be the nearest approach to a wild grass, and I shall try in further experiments to introduce other changes such as an increase of fertile flowers per spikelet, the reduction of difference between terminal and lateral inflorescences, etc.. But the nature of the atavistic reversion is alveadwy such that it alters considerably our expectation when looking for a still existing wild ancestor of corn. 9) The next step in our deductions must now consist in an reversion of our question. We must now explain how we may obtain domesticated corn, starting from a hypothetical wild plant, similar to type c. Of the several changes which must have been necessary to attract the attention of the Indians, the following two seem to me the most important: the disappearance of all abscission layers and the reduction of the glumes. This may have been brought about by an accumulation of mutations. But it seems much more probable to assume that some crossing with a tripsacoid grass or even with Tripsacum australe may have been responsible. In such a cross, the two types of abscission layer would be counterbalanced as shown by the Flhybrids of corn, Tripsacum and Euchlaena. Furthermore in later generations a.tu-allele of Tripsacum may become homozygous and substitute the wild tunicate factor of corn. The hypothesis of a hybrid origin of cultivated corn is not completely new, but has been discussed already by HARSHBERGER and COLLINS. Our hypothesis differs from that of MANGELSDORF and REEVES who assume that crosses with Tripsacum are responsible only for some features of Central and North American corn. 10) The following arguments give indirects evidence in support of our hypothesis: a) Several characters have been observed in indigenous corn from the central region of South America, which may be interpreted as "tripsacoid". b) Equally "zeoid" characters seem to be present in Tripsacum australe of central South-America. c) A system of unbalanced factors, combined by the in-tergeneric cross, may be responsible for the sterility of the wild type tunicata factor when homozygous, a result of the action of modifiers, brought in from Tripsacum together with the tuallele. d) The hybrid theory may explain satisfactorily the presence of so many lethals and semilethals, responsible for the phenomenon of inbreeding in cultivated corn. It must be emphasized that corn does not possess any efficient mechanism to prevent crossing and which could explain the accumulation of these mutants during the evolutionary process. Teosinte which'has about the same mechanism of sexual reproduction has not accumulated such genes, nor self-sterile plants in spite of their pronounced preference for crossing. 11) The second most important step in domestication must have consisted in transforming a four rowed ear into an ear with many rows. The fusion theory, recently revived byLANGHAM is rejected. What happened evidently, just as in succulent pXants (Cactus) or in cones os Gymnosperms, is that there has been a change in phyllotaxy and a symmetry of longitudinal rows superimposed on the original spiral arrangement. 12) The geographical distribution of indigenous corn in South America has been discussed. So far, we may distinguish three zones. The most primitive corn appears in the central lowlands of what I call the Central Triangle of South America: east of the Andies, south of the Amazone-Basin, Northwest of a line formed by the rivers São Prancisco-Paraná and including the Paraguay-Basin. The uniformity of the types found in this extremely large zone is astonishing (BRIEGER and CUTLER). To the west, there is the well known Andian region, characterized by a large number of extremely diverse types from small pop corn to large Cuszco, from soft starch to modified sweet corn, from large cylindrical ears to small round ears, etc.. The third region extends along the atlantic coast in the east, from the Caribean Sea to the Argentine, and is characterized by Cateto, an orange hard flint corn. The Andean types must have been obtained very early, and undoubtedly are the result of the intense Inca agriculture. The Cateto type may be obtained easily by crosses, for instance, of "São Paulo Pointed Pop" to some orange soft corn of the central region. The relation of these three South American zones to Central and North America are not discussed, and it seems essential first to study the intermediate region of Ecuador, Colombia and Venezuela. The geograprical distribution of chromosome knobs is rapidly discussed; but it seems that no conclusions can be drawn before a large number of Tripsacum species has been analysed.

Secure Bluetooth Audio Transmission System

The growing spread of small but powerful mobile devices (such as PDAs, mobile phone, Internet Tablet, etc.) opens up new scenarios in which users can interact with such devices in many environments in order to access the information at different locations. In this thesis, a ubiquitous computing based system called Secure Bluetooth Audio Transmission System is introduced. This system is situated in a large public place (like airport, festival venues, etc.), where voice messages are conveyed from the system to users' Bluetooth headsets in order to inform users the latest flight schedule and other public information. The reliability of the message is secured by adopting an authorization strategy and ECDSA. In order to assess and evaluate the risks and potential weaknesses of the system, an easy-to-use prototype implementation was written and tested. Other possible uses and further research were also considered.

Characterization of Lubricating Oil Using Ultrasound

This paper presents an ultrasonic method to measure small concentrations of water in lubricating oil. It uses an ultrasonic measurement cell composed by a piezoceramic emitter (5 and 10 MHz), and a large aperture PVDF receiver that eliminates diffraction effects. The propagation velocity, attenuation coefficient and density of several samples of water-in-oil emulsion were measured. The concentrations of water of the samples were in the range of 0 to 5% in volume, and the results showed that these low concentrations can be discriminated within a resolution of 0.2% in the studied range, using the measurement of the propagation velocity.

Memorias Congreso internacional de derecho comercial presente y futuro del derecho comercial : mayo 5 y 6 de 2010

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Lo urbano en lo rural : transformación del espacio periurbano y la creación de las necesidades

Tesis (Maestría en Ciencias con Orientación en Trabajo Social) U.A.N.L.