Towards Optimal Testing of Auditory Memory : Methodological development of recording of the mismatch negativity (MMN) of the auditory event-related potential (ERP)

The overlapping sound pressure waves that enter our brain via the ears and auditory nerves must be organized into a coherent percept. Modelling the regularities of the auditory environment and detecting unexpected changes in these regularities, even in the absence of attention, is a necessary prerequisite for orientating towards significant information as well as speech perception and communication, for instance. The processing of auditory information, in particular the detection of changes in the regularities of the auditory input, gives rise to neural activity in the brain that is seen as a mismatch negativity (MMN) response of the event-related potential (ERP) recorded by electroencephalography (EEG). --- As the recording of MMN requires neither a subject s behavioural response nor attention towards the sounds, it can be done even with subjects with problems in communicating or difficulties in performing a discrimination task, for example, from aphasic and comatose patients, newborns, and even fetuses. Thus with MMN one can follow the evolution of central auditory processing from the very early, often critical stages of development, and also in subjects who cannot be examined with the more traditional behavioural measures of auditory discrimination. Indeed, recent studies show that central auditory processing, as indicated by MMN, is affected in different clinical populations, such as schizophrenics, as well as during normal aging and abnormal childhood development. Moreover, the processing of auditory information can be selectively impaired for certain auditory attributes (e.g., sound duration, frequency) and can also depend on the context of the sound changes (e.g., speech or non-speech). Although its advantages over behavioral measures are undeniable, a major obstacle to the larger-scale routine use of the MMN method, especially in clinical settings, is the relatively long duration of its measurement. Typically, approximately 15 minutes of recording time is needed for measuring the MMN for a single auditory attribute. Recording a complete central auditory processing profile consisting of several auditory attributes would thus require from one hour to several hours. In this research, I have contributed to the development of new fast multi-attribute MMN recording paradigms in which several types and magnitudes of sound changes are presented in both speech and non-speech contexts in order to obtain a comprehensive profile of auditory sensory memory and discrimination accuracy in a short measurement time (altogether approximately 15 min for 5 auditory attributes). The speed of the paradigms makes them highly attractive for clinical research, their reliability brings fidelity to longitudinal studies, and the language context is especially suitable for studies on language impairments such as dyslexia and aphasia. In addition I have presented an even more ecological paradigm, and more importantly, an interesting result in view of the theory of MMN where the MMN responses are recorded entirely without a repetitive standard tone. All in all, these paradigms contribute to the development of the theory of auditory perception, and increase the feasibility of MMN recordings in both basic and clinical research. Moreover, they have already proven useful in studying for instance dyslexia, Asperger syndrome and schizophrenia.

Studies on follicular growth in the immature rat and hamster: Effect of a single injection of gonadotropin or estrogen on the rate of3H-thymidine incorporation into ovarian DNAin vitro

Initiation of follicular growth by specific hormonal stimuli in ovaries of immature rats and hamsters was studied by determining the rate of incorporation of3H-thymidine into ovarian DNAin vitro. Incorporation was considered as an index of DNA synthesis and cell multiplication. A single injection of pregnant mare serum gonadotropin could thus maximally stimulate by 18 hr3H-thymidine incorporation into DNA of the ovary of immature hamsters. Neutralization of pregnant mare serum gonadotropin by an antiserum to ovine follicle stimulating hormone only during the initial 8–10 hr and not later could inhibit the increase in3H-thymidine incorporationin vitro observed at 18 hr, suggesting that the continued presence of gonadotropin stimulus was not necessary for this response. The other indices of follicular growth monitored such as ovarian weight, serum estradiol and uterine weight showed discernible increase at periods only after the above initial event. A single injection of estrogen (diethyl stilbesterol or estradiol-l7β) could similarly cause 18 hr later, a stimulation in the rate of incorporation of3H-thymidine into DNAin vitro in ovaries of immature rats. The presence of endogenous gonadotropins, however, was obligatory for observing this response to estrogen. Evidence in support of the above was two-fold: (i) administration of antiserum to follicle stimulating hormone or luteinizing hormone along with estrogen completely inhibited the increase in3H-thymidine incorporation into ovarian DNAin vitro; (ii) a radioimmunological measurement revealed following estrogen treatment, the presence of a higher concentration of endogenous follicle stimulating hormone in the ovary. Finally, administration of varying doses of ovine follicle stimulating hormone along with a constant dose of estrogen to immature rats produced a dose-dependent increment in the incorporation of3H-thymidine into ovarian DNAin vitro. These observations suggested the potentiality of this system for developing a sensitive bioassay for follicle stimulating hormone.

Inhibition of protein synthesis leading to unfolded protein response is the major event in abrin-mediated apoptosis

Abrin obtained from the plant Abrus precatorius inhibits protein synthesis and also triggers apoptosis in cells. Previous studies from our laboratory suggested a link between these two events. Using an active site mutant of abrin A-chain which exhibits 225-fold lower protein synthesis inhibitory activity than the wild-type abrin A-chain, we demonstrate in this study that inhibition of protein synthesis induced by abrin is the major factor triggering unfolded protein response leading to apoptosis. Since abrin A-chain requires the B-chain for internalization into cells, the wild-type and mutant recombinant abrin A-chains were conjugated to native ricin B-chain to generate hybrid toxins, and the toxic effects of the two conjugates were compared. The rate of inhibition of protein synthesis mediated by the mutant ricin B-rABRA (R167L) conjugate was slower than that of the wild-type ricin B-rABRA conjugate as expected. The mutant conjugate activated p38MAPK and caspase-3 similar to its wild-type counterpart although at later time points. Overall, these results confirm that inhibition of protein synthesis is the major event contributing to abrin-mediated apoptosis.

Discovering compressing serial episodes from event sequences

Most pattern mining methods yield a large number of frequent patterns, and isolating a small relevant subset of patterns is a challenging problem of current interest. In this paper, we address this problem in the context of discovering frequent episodes from symbolic time-series data. Motivated by the Minimum Description Length principle, we formulate the problem of selecting relevant subset of patterns as one of searching for a subset of patterns that achieves best data compression. We present algorithms for discovering small sets of relevant non-redundant episodes that achieve good data compression. The algorithms employ a novel encoding scheme and use serial episodes with inter-event constraints as the patterns. We present extensive simulation studies with both synthetic and real data, comparing our method with the existing schemes such as GoKrimp and SQS. We also demonstrate the effectiveness of these algorithms on event sequences from a composable conveyor system; this system represents a new application area where use of frequent patterns for compressing the event sequence is likely to be important for decision support and control.

La construcción literaria de personajes históricos en la Crónica de Sancho IV

Resumen: El valor estético de la Crónica de tres reyes siempre ha sido puesto en entredicho a raíz de su estilo neutro que contrasta con el de otras obras del género, como ser las crónicas de Alfonso X y las de Pero López de Ayala. El presente trabajo se encarga de estudiar los procedimientos narrativos a través de los cuales algunos de sus personajes son confi gurados en función de asignar a la trama de los acontecimientos un determinado sentido político que se distancia de otras versiones de los hechos que circulaban en el período, como por ejemplo la "Historia hasta 1288 dialogada".

Construcciones científicas del teatro: la pregunta epistemológica en los estudios teatrales

Resumen: El artículo afirma que en la Teatrología argentina de los últimos años ha crecido la conciencia y la responsabilidad de los investigadores respecto de la pregunta epistemológica. Se llama base epistemológica para el estudio teatral a la elección de las condiciones de conocimiento que determinan los marcos, las capacidades y las limitaciones teóricas, metodológicas, historiológicas, analíticas, críticas y pedagógicas de un investigador ante su objeto de estudio. La determinación de la base epistemológica depende del posicionamiento consciente del investigador respecto de su relación científica con el teatro. El artículo afirma que diferentes líneas científicas construyen concepciones del teatro diferentes. Finalmente se describe la base epistemológica de la Filosofía del Teatro, disciplina de innovación en los estudios teatrales de la Argentina.

Antiguo Oriente: Cuadernos del Centro de Estudios de Historia del Antiguo Oriente, 2008, n° 6 (número completo)

Sumario -- The pottery of Edom: A Correction / Israel Finkelstein & Lily Singer-Avitz -- The Jezirah Burnished Ware / Stefano Valentini -- The Cordage from Berenike (1994-2000): The Statics / André J. Veldmeijer -- A Reevaluation of the Use of !bz and bhy in Elephantine / Alejandro F. Botta -- Four Ur III Administrative Tablets in the Possesion of Professor Francis Carroll, University of Manitoba / John Nielsen -- Una actualización de la Cronología Baja: arqueología, historia y Biblia / Israel Finkelstein -- The Alleged “Anchor Point” of 732 BC for the Destrction of Hazor V / Peter James -- The “Wicked Priest” in Egyptology and Amarna Studies: A Reconsideration / Samuel Jackson -- Violencia fenicia en el Mediterráneo Oriental / Jordi Vidal -- Reportes de Excavación -- The Leatherwork from Deir el-Bachit: Preliminary Report / André J. Veldmeijer -- Reseñas bibliográficas -- Política editorial e instrucciones para los colaboradores -- Direcciones para envío de artículos y reseñas bibliográficas -- Colaboraciones en numeros anteriores

De los grandes relatos a los estudios de “pequeña escala” : algunas notas acerca de la historiografía del primer peronismo

Resumen: Existen varias posibilidades a la hora de analizar las distintas corrientes en la historiografía reciente del peronismo; sin embargo, en líneas generales, se puede decir que a lo largo de los años el foco del debate se ha trasladado de los sociólogos a los historiadores, de las perspectivas macro a las micro y de lo político a lo social. El énfasis inicial acerca de la supuesta ruptura y anomalía que representaba el peronismo ha prácticamente desaparecido a favor de la continuidad y de su contextualización en el proceso histórico argentino. La imagen homogénea ha sido reemplazada por un cuadro complejo y heterogéneo. Desde la perspectiva de los estudios de género, las investigaciones sobre el peronismo han producido no solamente trabajos sobre el Partido Peronista Femenino, sino otros que también han explorado temas como la reproducción, la maternidad, la infancia y las dinámicas familiares. Asimismo, la dimensión nacional, basada en la experiencia de la Capital Federal y sus alrededores, es decir la óptica metropolitana, ha dado lugar a distintas miradas provinciales, regionales y locales. Con cierta exageración se podría hablar de un desplazamiento de los grandes relatos y los modelos teóricos a los estudios de pequeña escala de la vida cotidiana bajo el peronismo.

Key business factors for eco-innovation: an overview of recent firm-level empirical studies

[EN] The increasing interest in eco-innovation or environmental innovation as a strategy not only to address the serious global environmental problems but also as a source of competitive advantages for companies and for the emergence of new business areas, leads us to try to identify the different factors that act as determinants of its development and adoption at the micro level.

Evaluación de la actividad investigadora: indicadores de calidad. Utilización de bases de datos en estudios bibliométricos.

[ES]La utilización de indicadores bibliométricos como los índices de citas y el factor de impacto se han convertido en herramientas imprescindibles tanto para la evaluación de la actividad investigadora como para la medición de la actividad económica y social de un país. El artículo analiza los indicadores para la evaluación de la calidad en la actividad investigadora y profundiza en la utilización de las bases de datos como herramienta de estudios bibliométricos.

Una aproximación a la situación de la mujer en los estudios universitarios de informática

[ES]En los últimos años, la baja participación de la mujer y la tendencia al descenso de los porcentajes de alumnas matriculadas en los estudios universitarios de informática ha sido objeto de estudio para investigadoras/es en Estados Unidos, Europa y otros países. Habiendo constatado también en la Facultad de Informática de San Sebastián (FISS) de la Universidad del País Vasco (UPV/EHU) dicho descenso, nuestro objetivo ha sido recopilar información estadística para determinar si esta tendencia se ha producido también en otras universidades del Estado español. El estudio incluye, en primer lugar,porcentajes de mujeres inscritas en Ingeniería Informática comparados con los porcentajes en el área técnica en su conjunto. Por otra parte, recoge datos del tercer ciclo y porcentajes de profesoras de los departamentos que imparten docencia en la FISS, comparados con los porcentajes en los mismos departamentos en el conjunto del Estado. Por último, se presentan datos de inserción en el mundo laboral para las promociones 1998-2002 de egresadas/os en la UPV/EHU. Los datos revelan los bajos porcentajes de mujeres que se han matriculado en Ingeniería Informática los últimos años y la tendencia al descenso, las diferencias entre distintas universidades,y que apenas hay sesgo de género en los datos de inserción en el mundo laboral.

Studies of physical, chemical, and biological oceanography in the vicinity of the Revilla Gigedo Islands during the “Island Current Survey” of 1957

ENGLISH: The tendency of the tunas, especially the yellowfin (Neothunnus macropterus) to be more abundant in the near vicinity of islands and seamounts, or "banks", than in the surrounding oceanic areas, is well known to commercial fishermen. This has been confirmed by statistical analysis of fishing vessel logbook records, which demonstrates that the catch-per-day's-fishing is, indeed, higher in the near vicinity of these features. It is hypothesized that islands and seamounts cause changes in the physical circulation or the biochemical cycle resulting in greater supplies of food for tunas in their immediate environs. In order to examine this hypothesis, and in order to study possible mechanisms involved, the "Island Current Survey" was undertaken from 8 May to 12 June, 1957, under the joint auspices of the Inter-American Tropical Tuna Commission and the Scripps Institution of Oceanography. Surveys of varying nature and extent were made from M/V Spencer F. Baird near Alijos Rocks, Clarion Island, Shimada Bank and Socorro Island (Figure 1). These studies sought to provide knowledge of the action of islands and seamounts in arresting, stalling or deflecting the mean current past them, in establishing convergence and divergence in the surface flow, in producing vertical motion (mixing and upwelling), and in influencing the primary production and the standing crops of phytoplankton and zooplankton. Each survey is discussed below in detail. Observations made at a front on 10 June will be discussed in another paper. SPANISH: Los pescadores que realizan la pesca comercial conocen muy bien la tendencia de los atunes, en particular del atún aleta amarilla (Neothunnus macropterus), de presentarse en mayor abundancia en las cercanías inmediatas a las islas y cimas submarinas, o "bancos", que en las áreas oceánicas circundantes. Este hecho ha sido confirmado par el análisis estadístico de los registros de los cuadernos de bitácora de las embarcaciones pesqueras, demostrándose que la captura par dias de pesca es, en efecto, más abundante en la inmediata proximidad de tales formaciones. Hipotéticamente se admite que las islas y las cimas submarinas provocan cambios en la circulación física o en el ciclo bioquímico, lo cual se pone de manifiesto a través de un mejor abastecimiento de alimento para los atunes en sus cercanías inmediatas. Con la finalidad de verificar esta hipótesis y de estudiar los mecanismos que ella involucra, se realizó la “Island Current Survey” del 8 de mayo al 12 de junio de 1957, bajo los auspicios de la Comisión Interamericana del Atún Tropical y de la Institución Scripps de Oceanografia. Con el barco Spencer F. Baird se hicieron observaciones de distintas clases y alcances cerca de las Rocas Alijos, la Isla Clarion, el Banco Shimada y la Isla Socorro (Figura 1). Estos estudios tuvieron por objeto adquirir conocimientos sobre la acción que ejercen las islas y cimas submarinas sobre la corriente promedio, ya sea deteniéndola, reduciendo su velocidad o desviando su curso, así como estableciendo convergencia o divergencia en su flujo de superficie, o provocando un movimiento vertical (mezcla y afloramiento) e influyendo en la producción primaria y en las existencias de fitoplancton y zooplancton. Cada operación será tratada a continuación por separado. Las observaciones hechas el dia 10 de junio sobre un frente serán objeto de otra publicación.

Sensor networks for geospatial event detection - theory and applications

This thesis presents theories, analyses, and algorithms for detecting and estimating parameters of geospatial events with today's large, noisy sensor networks. A geospatial event is initiated by a significant change in the state of points in a region in a 3-D space over an interval of time. After the event is initiated it may change the state of points over larger regions and longer periods of time. Networked sensing is a typical approach for geospatial event detection. In contrast to traditional sensor networks comprised of a small number of high quality (and expensive) sensors, trends in personal computing devices and consumer electronics have made it possible to build large, dense networks at a low cost. The changes in sensor capability, network composition, and system constraints call for new models and algorithms suited to the opportunities and challenges of the new generation of sensor networks. This thesis offers a single unifying model and a Bayesian framework for analyzing different types of geospatial events in such noisy sensor networks. It presents algorithms and theories for estimating the speed and accuracy of detecting geospatial events as a function of parameters from both the underlying geospatial system and the sensor network. Furthermore, the thesis addresses network scalability issues by presenting rigorous scalable algorithms for data aggregation for detection. These studies provide insights to the design of networked sensing systems for detecting geospatial events. In addition to providing an overarching framework, this thesis presents theories and experimental results for two very different geospatial problems: detecting earthquakes and hazardous radiation. The general framework is applied to these specific problems, and predictions based on the theories are validated against measurements of systems in the laboratory and in the field.