University of Cádiz
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El yeísmo en el español de América: registro espontáneo versus registro leído
Get PDFEl yeísmo es un cambio lingüístico de carácter fonético y fonológico que consiste en la sustitución
del fonema lateral palatal [ ʎ ] por el aproximante palatal [j]. Este fenómeno se encuentra presente en
el español, no solo en el de España, sino también en el de América, por lo que en este trabajo nos
centraremos en estudiar la aparición del yeísmo en el habla de personas hispanoamericanas. Para
ello, analizaremos algunas grabaciones de audio de hablantes procedentes de distintos orígenes
geográficos de Hispanoamérica, lo cual nos permitirá obtener datos acerca de la presencia del
fenómeno yeísta en su habla. De esta manera, podremos estudiar si la aparición del yeísmo y sus
diferentes tipos se supedita a factores de carácter lingüístico o extralingüístico y, además,
investigaremos si estos datos coinciden con los diversos estudios existentes hasta la fecha acerca de
este fenómeno en el habla de Hispanoamérica.Yeísmo is a linguistic change of a phonetic and phonological nature which consists of the
replacement of the palatal lateral phoneme [ ] by the palatal approximant [j]. This phenomenon is ʎ
present in Spanish, not only in Spain, but also in America; that is why in this work I will focus on
the emergence of yeísmo in the speech of Spanish-speaking people from Hispanic America. In order
to do so, I have compiled several audio recordings of speakers from different geographical origins
within Hispanic America, which will allow for determining the presence of the yeísta phenomenon
in their speech. Thus, I will be able to study whether the appearance of yeísmo and its different
types is conditioned by linguistic and extralinguistic factors and I will also investigate if my
findings coincide with the statements of numerous existing studies on the actuality of this
phenomenon in American Spanish
Sistema de monitorización de tráfico en directo mediante detección de objetos basada en Deep Learning
Get PDFEn un contexto donde la movilidad urbana eficiente y la seguridad vial son desafíos crecientes para las ciudades, se vuelve imprescindible desarrollar soluciones tecnológicas que permitan una gestión inteligente del tráfico. Aprovechando las tecnologías emergentes, en este trabajo se propondrá un sistema de monitoreo de tráfico en tiempo real que utiliza técnicas de Deep Learning para detectar y seguir vehículos de manera automática a partir de fuentes de vídeo en vivo. La plataforma captura flujos de vídeo, preprocesa las imágenes para enfocar áreas de interés y utiliza un modelo de inteligencia artificial entrenado para identificar y rastrear vehículos, generando conteos y estadísticas de circulación que permiten predecir flujos futuros. Estos datos se presentan a través de una API web moderna y se almacenan periódicamente en una base de datos, lo que facilita el análisis histórico y la integración con soluciones de gestión urbana y seguridad vial. Gracias a su arquitectura, el sistema puede adaptarse tanto a entornos de prueba como a implementaciones en ciudades de diferentes tamaños, proporcionando información clave para optimizar la movilidad y reducir la congestión
Pleural Fluid Biomarkers of Pediatric Parapneumonic Effusion
Get PDFBackground/Objectives: Parapneumonic pleural effusion (PPE) secondary to community-acquired pneumonia is the most common cause of pediatric pleural effusion. This study aimed to evaluate the pleural fluid characteristics of pediatric patients with PPE and to compare biomarkers between infants (1–12 months) and children (1–14 years). Methods: Fifty-four pediatric patients (14 infants and 40 children) with PPE were included. Pleural fluid samples were analyzed for white blood cell (WBC) count, glucose, total protein, lactate dehydrogenase (LDH), adenosine deaminase (ADA), and pH levels. Differences between age groups and correlations between age and pleural fluid biomarkers were assessed. Results: Most pediatric PPE cases exhibited biochemical characteristics consistent with pleural exudate: WBC > 1000 cells/µL, total protein > 3 g/dL, LDH > 200 U/L. Infants showed a predominance of mononuclear WBC, while children exhibited a predominance of polymorphonuclear WBC. Glucose levels were higher, and total protein levels were lower in infants compared to children. Age was positively correlated with polymorphonuclear WBC percentage (rho = 0.509, p < 0.001) and protein levels (rho = 0.622, p < 0.001), whereas glucose levels were negatively correlated with age (rho = −0.274, p = 0.043). Conclusions: Age-specific differences in pleural fluid biomarkers were observed in pediatric patients with PPE, suggesting a more robust and acute inflammatory response in children compared to infants. These findings underscore the importance of considering age-related variations in the inflammatory response when diagnosing and managing PPE in pediatric populations
Enhancing the Production of H2 and Volatile Fatty Acids by Fungal Pretreatment of Invasive Macroalgae (Rugulopteryx okamurae) Followed by Dark Fermentation
Get PDFThe blue economy promotes the sustainable use of marine resources, such as algae, for socioeconomic development. This study aims to increase the production of hydrogen (H2) and volatile fatty acids (VFA) through the dark fermentation of the invasive macroalga Rugulopteryx okamurae. Batch experiments were conducted to identify the optimal operating conditions, with the following parameters being varied: inoculum-substrate ratio (IS) (0.43, 0.25, and 0.11 v/v); initial pH (5.5, 6.5, and 7.5); and algal suspension concentration (4, 6, 8, and 10% w/v). Additionally, the impact of biological pretreatment using Aspergillus awamori was assessed. This was performed via solid-state fermentation (SSF) at two fungal inoculum concentrations (10^7 and 10^8 cel/gbiomass) and two incubation times (5 and 8 days). The highest H2 yield (9.49 mLH2/gbiomass) was obtained after 8 days of pretreatment with 10^7 cel/gbiomass, whereas the greatest TVFA production (213 mg of acetic acid equivalents/gbiomass) occurred after 5 days using 10^8 cel/gbiomass. These results suggest that biological pretreatment can enhance the performance of dark fermentation and that the latter condition is most suitable for VFA-oriented biorefineries
Analysis of factors with an impact on the academic performance of Contabilidad de Gestión students: a quantitative and qualitative approach.
Get PDFHoy en día el rendimiento académico de los estudiantes es una preocupación constante
en la sociedad, especialmente en el entorno universitario, dónde no solo se busca superar
las asignaturas, sino también formar a profesionales competentes alineándose con el
Objetivo de Desarrollo Sostenible 4: Educación de calidad.
Este trabajo analiza los factores que influyen en el rendimiento académico de los
estudiantes que cursan la asignatura “Contabilidad de Gestión”, a partir del modelo 3P
(Presagio-Proceso-Producto), identificado a partir de la revisión bibliográfica realizada
3
previamente. La investigación combina un estudio cuantitativo, realizado mediante un
cuestionario, y un análisis cualitativo a partir de entrevistas, dicha investigación es aplicada
a estudiantes del Grado en Administración y Dirección de Empresas y a estudiantes del Doble
Grado en Administración y Dirección de Empresas con Finanzas y Contabilidad, para poder
obtener información sobre los estudiantes que cursan la Mención de Negocios
Internacionales.
En la fase cuantitativa, en los cuestionarios se emplean escalas tipo dicotómicas, Likert
y de intervalos con el fin de estudiar los diferentes factores como el interés y motivación
personal, la asistencia a clase y métodos de aprendizaje, analizados mediante el software
SPSS para obtener resultados estadísticos que nos permitan contrastar las hipótesis
diseñadas. El análisis cualitativo profundiza en los aspectos internos de los estudiantes para
completar la información que proporciona los datos estadísticos con el fin de crear
conclusiones fiables.
Por último, se obtiene una relación significativa entre los factores presagio y de proceso
con el rendimiento académico. Este estudio aporta evidencias empíricas con el fin de
contribuir a una docencia universitaria centrada en el estudiante.Nowadays, the academic performance of students is a constant concern in society,
especially in the university environment, where the aim is not only to pass the subjects, but
also to prepare competent professionals in line with Sustainable Development Goal 4: Quality
Education.
The present research analyses the factors that influence the academic performance of
students enrolled in the subject “Contabilidad de Gestión”, based on the 3P model (PresageProcess-Product), identified from the previous literature review. The research combines a
quantitative study, carried out by a questionnaire, and a qualitative analysis based on
interviews, this research is applied to students of the Degree in Business Administration and
Management and to students of the Double Degree in Business Administration and
Management with Finance and Accounting, in order to obtain information about the students
studying the International Business Mention.
In the quantitative stage, dichotomous, Likert and interval scales are used in the
questionnaires in order to study the different factors such as personal interest and
motivation, class attendance and learning methods, analysed using SPSS software to obtain
statistical results that allow the designed hypotheses to be contrasted. The qualitative
analysis focuses on the internal aspects of the students to complete the information provided
by the statistical data in order to create reliable conclusions.
Finally, a significant relationship is obtained between the omen and process factors with
academic performance. This study provides empirical evidence in order to contribute to
student-centred university teaching
Criterion-related validity and reliability of the 6-minute walk test in adults according to sex, age and physical activity level: The ADULT-FIT project
Get PDFThis study aimed to analyse the criterion-related validity and reliability of the 6-minute walk test (6MWT) to assess cardiorespiratory fitness in the adult population, according to sex, age and physical activity level.
Sociodemographic and anthropometric measurements, a treadmill maximal test, and the 6MWT were performed on 410 adults aged 18–64 years.
Measured VO2max was associated with the total distance in the 6MWT and estimated VO2max by Burr´s and Manttari´s equations (R2= 0.35, 0.61 and 0.61, respectively, all p< 0.01; SEE= 6.564 - 5.089 ml* kg-1 * min-1, %SEE= 11.80 – 15.30). The stepwise linear regression analysis showed that the total distance in the 6MWT, sex, age, physical activity level and body fat mass (%) explained 75% variance of measured VO2max (SEE= 4.203 ml* kg-1 * min-1, %SEE= 9.78, p< 0.001). The systematic error in the total distance in the 6MWT was 0.87-m (p< 0.001). The ICC showed excellent agreement (0.99, p< 0.001), with low error values and most of the MCD95 close to 0.
The 6MWT was valid and reliable to assess cardiorespiratory fitness in adults aged 18–64 years. Validity was greater in the older age and non-active groups. Reliability did not depend on sex, age, nor physical activity level
MICHAEL BRAUN, Ingmar. (2022): Ausgewählte Säugetierdarstellungen in der Eiszeitkunst und der Versuch ihrer zoologisch-ethologischen Interpretation. Universitätsforschungen zur prähistorischen Archäologie, Band 373, Aus dem Institut für Ur- und Frühgeschichte und Archäologie des Mittelalters der Universität Tübingen, Abt. Ältere Urgeschichte und Quartärökologie. Verlag Dr. Rudolf Habelt GmbH, Bonn Alemania. 234 páginas 501 figuras. ISBN: 978-3-77 49-4326-1.
Get PDFLa edición de este volumen corresponde a la
tesis doctoral presentada por el Dr. Braun en la
Universidad de Tübingen en diciembre del año
2020 y dirigida por el Dr. Harald Floss. Con una
vocación muy precoz el autor de este trabajo, durante su etapa de formación ha contactado con
la mayoría de los profesionales del arte rupestre
europeo. Organiza visitas guiadas a las cavidades
de la Cornisa Cantábrica y a otros yacimientos arqueológicos con ciudadanos interesados en el patrimonio prehistórico
Predictive modelling and coastal storm responsea study of urban and natural coastal systems
Get PDFThe increase in frequency and intensity of storm events combined with the growth of population in the coastal zones are exacerbating risk in coastal areas . Proper mitigation plans are necessary to reduce the impact of extreme events on those areas. In many cases, the development of those plans is based on early warning systems, a combination of pre-established extreme values and numerical models to forecast the storm's possible impact. However, the local characteristics must be considered when establishing the extreme values and setting the numerical models to achieve reliable predictions.
This PhD thesis presents the study of the application of numerical modelling to predict coastal storm behaviour in two sites with opposite characteristics: Urban and Natural systems. The chosen highly urbanised beach was the beach of Volano in the Emilia-Romagna region in Italy, while the considered natural coastal system was the Arborea Beach in Sardinia (Italy); the last one is characterised by the presence of seagrass Posidonia oceanica deposition on the foreshore, known as "banquette". The thesis comprehensively evaluates these models' role in predicting and mitigating coastal hazards by investigating the two different environments.
The first topic addressed in this thesis is the flooding risk in urban areas, with the specific case study in the Emilia-Romagna region. The coastal area of this Italian region, located on the northern Adriatic coast, is heavily urbanised due to the presence of resorts, roads and coastal defences. The high infrastructure in a low-lying dune area makes the region susceptible to extreme events, being impacted at least once yearly. When defining the warning levels in a forecasted event, a common practice is establishing different thresholds according to the event's intensity. One standard value is the Total Water Level (TWL). However, the definition of TWL and how the extreme values are calculated change from country to country or even region to region. This can go from including different components to calculating the TWL components such as sea level, tidal components, wave setup, and storm surge or calculating the extreme value by combining individual extreme values or extracting directly by a combined time series. The different methodologies for calculating the extreme TWL were applied to the coastal area of Volano and then applied to the numerical model LISFLOOD-FP to observe their impact.
The results of this section highlight the sensitivity of the numerical model to the different inputs, such as the inclusion of the wave runup in the TWL. To define the best TWL definition and method to calculate the extreme value, a storm that occurred on this coast on 22 November 2022 was used as a real-case scenario. Compared to the event, the best combination and method found was combining the individual components' time series into a common time series and the respective extracted values.
The second topic of the thesis changes the focus to a natural coastal system, examining the role of Posidonia oceanica banquettes in protecting beaches from storm-induced erosion. Arborea Beach, located on the island of Sardinia, was selected due to the undisturbed natural environment and the frequent presence of Posidonia oceanica banquettes on the beach. Posidonia oceanica is banquettes, and their meadows are important in the beach's wave action effects. Over the years (2022-2024), extensive fieldwork was done covering the topography and bathymetry of Arborea Beach, and this was also combined with historical data collected from aerial data. The study demonstrated that banquettes can act as natural buffers of wave action, preventing erosion. The study also compared different sections of the beach, revealing that areas with dense Posidonia banquettes experienced significantly less erosion when compared with areas with fewer banquettes. This demonstrated the importance of banquettes in maintaining the beach's stability, although not entirely sufficient for nullifying erosion. The overall trend of the study area is eroding, suggesting a possible lack of sediment supply.
The third Chapter focuses on using the fieldwork's high-quality data to explore the limitations of the current numerical modes in simulating the formation and protective characteristics of Posidonia oceanica banquettes. A widely used morphohydrodynamic model, XBeach, was used to simulate the impact of a storm on the Arborea beach. Two scenarios were tested: i) one where the beach morphology remained static, analysing the runup extension, and ii) another where the capability to simulate the development of banquettes on the beach was tested.
The results of the simulation were compared with the fieldwork observations. While the XBeach accurately simulated the hydrodynamics during the event on a static morphology, it struggled to simulate the development of Posidonia banquettes. The model's inability to simulate the organic structure highlighted a current limitation of the current numerical models. This emphasises that the numerical models need improvements to include characteristics crucial to coastal protection. Future advancements in coastal modelling should incorporate better representation of those characteristics.
Overall, the thesis highlights the need to adopt a mitigation plan according to the local areas; where the urban area is more focused on flood propagation, the natural area's adaptation requires a good morphological prediction. The combination of the prediction of both sectors would show the best results overall. However, this would require constant monitoring of the areas of interest. The constant monitoring of the beach and the proper calibration will allow the coastal managers to improve the coastal storm predictions and, therefore, anticipate and mitigate the impacts of extreme.
In future research, the thesis recommends expanding the field of coastal modelling to include more comprehensive simulations of the peculiar characteristics of specific environments. Furthermore, continued improvement in data collection methods, such as the use of high-resolution satellite imagery and advanced monitoring systems, will be essential to enhance the predictive accuracy of these models
Homenaje al doctor don Francisco Herrera Rodríguez: catedrático de Historia de la Enfermería
Get PDFUn afectuoso homenaje a don Francisco Herrera, unido al autor por un
gran vínculo de amistad, admiración y cariño.An affectionate tribute to Mr. Francisco Herrera, united to the author by
a great bond of friendship, admiration, and affection
Realidad aumentada, una tecnología estratégica para impulsar el aprendizaje en las aulas universitarias
Get PDFDiversas tecnologías emergentes, como la realidad aumentada (RA), se encuentran
transformando la educación superior al ofrecer experiencias inmersivas e interactivas que
fortalecen los procesos de enseñanza y aprendizaje. Este estudio analiza la integración de la RA
en la formación docente mediante el curso Realidad Aumentada en la Educación, impartido en la
Universidad Autónoma de Baja California (UABC) durante 2023-2 y 2024-1. Se empleó el
Modelo de Aceptación Tecnológica (TAM) para evaluar la percepción y actitud de los docentes
hacia la RA, utilizando un enfoque mixto basado en la recopilación y análisis de datos sobre
aceptación y utilidad percibida. Los resultados indican que el 97 % de los participantes consideró
intuitivos y aplicables los recursos de RA, y el 73 % integró esta tecnología en sus estrategias
didácticas, destacando su impacto en la motivación y comprensión del alumnado; sin embargo,
algunos docentes señalaron desafíos técnicos relacionados con dispositivos obsoletos y
conectividad. Se concluye que la RA es una herramienta valiosa para la educación superior, ya
que enriquece la enseñanza y el aprendizaje, pero su implementación requiere capacitación y
acceso a infraestructura tecnológica adecuada para optimizar sus beneficios en el aula
universitaria