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Epidemiology of ataxia and hereditary spastic paraplegia in Spain: a cross-sectional study
No full textIntroducción: Las ataxias (AT) y paraparesias espásticas hereditarias (PEH) son síndromes neurodegenerativos raros. Nos proponemos conocer la prevalencia de las AT y PEH en Espana˜ en
2019.
Pacientes y métodos: Estudio transversal, multicéntrico, descriptivo y retrospectivo de los
pacientes con AT y PEH, desde marzo de 2018 a diciembre de 2019 en toda Espana. ˜
Resultados: Se obtuvo información de 1933 pacientes procedentes de 11 Comunidades Autónomas, de 47 neurólogos o genetistas. Edad media: 53,64 anos ˜ ± 20,51 desviación estándar (DE);
938 varones (48,5%), 995 mujeres (51,5%). En 920 pacientes (47,6%) no se conoce el defecto
genético. Por patologías, 1.371 pacientes (70,9%) diagnosticados de AT, 562 diagnosticados de
PEH (29,1%). La prevalencia estimada de AT es 5,48/100.000 habitantes, y la de PEH es 2,24
casos/100.000 habitantes. La AT dominante más frecuente es la SCA3. La AT recesiva más frecuente es la ataxia de Friedreich (FRDA). La PEH dominante más frecuente es la SPG4, y la PEH
recesiva más frecuente es la SPG7.
Conclusiones: La prevalencia estimada de AT y PEH en nuestra serie es de 7,73 casos/100.000
habitantes. Estas frecuencias son similares a las del resto del mundo. En el 47,6% no se ha
conseguido un diagnóstico genético. A pesar de las limitaciones, este estudio puede contribuir
a estimar los recursos, visibilizar estas enfermedades, detectar las mutaciones más frecuentes
para hacer los screenings por comunidades, y favorecer los ensayos clínicos.Introduction: Ataxia and hereditary spastic paraplegia are rare neurodegenerative syndromes.
We aimed to determine the prevalence of these disorders in Spain in 2019.
Patients and methods: We conducted a cross-sectional, multicentre, retrospective, descriptive study of patients with ataxia and hereditary spastic paraplegia in Spain between March
2018 and December 2019. Results: We gathered data from a total of 1933 patients from 11 autonomous communities,
provided by 47 neurologists or geneticists. Mean (SD) age in our sample was 53.64 (20.51)
years; 938 patients were men (48.5%) and 995 were women (51.5%). The genetic defect was
unidentified in 920 patients (47.6%). A total of 1371 patients (70.9%) had ataxia and 562 (29.1%)
had hereditary spastic paraplegia. Prevalence rates for ataxia and hereditary spastic paraplegia
were estimated at 5.48 and 2.24 cases per 100 000 population, respectively. The most frequent
type of dominant ataxia in our sample was SCA3, and the most frequent recessive ataxia was
Friedreich ataxia. The most frequent type of dominant hereditary spastic paraplegia in our
sample was SPG4, and the most frequent recessive type was SPG7.
Conclusions: In our sample, the estimated prevalence of ataxia and hereditary spastic paraplegia was 7.73 cases per 100 000 population. This rate is similar to those reported for other
countries. Genetic diagnosis was not available in 47.6% of cases. Despite these limitations, our
study provides useful data for estimating the necessary healthcare resources for these patients,
raising awareness of these diseases, determining the most frequent causal mutations for local
screening programmes, and promoting the development of clinical trials
Unidades didácticas potencialmente significativas para la enseñanza y el aprendizaje de sistemas de ecuaciones de 1er grado basados en la teoría de aprendizaje significativo crítico
No full textAs dificuldades de ensino e aprendizagem de matemática constituem, muitas vezes, um entrave para o desenvolvimento integral dos estudantes e o pleno exercício da cidadania. Acredita-se que é possível promover aprendizagem significativa crítica a partir da aplicação de Unidades de Ensino Potencialmente Significativas (UEPS), fundamentadas nos princípios da TASC. Esta tese apresenta a análise da construção do conceito de sistema de equações do 1º grau com duas variáveis, aplicando uma UEPS, utilizando a estratégia de situações-problema como metodologia de ensino para promover aprendizagem significativa crítica no 8º ano do Ensino Fundamental do Colégio de Aplicação da Universidade Federal de Roraima (CAp/UFRR), Brasil. Foi necessário diagnosticar os conhecimentos prévios dos estudantes, elaborar, aplicar e avaliar a contribuição da UEPS, analisar o nível de compartilhamento de significados dos estudantes em relação ao conceito estudado; verificar quais dos 13 princípios da TASC influenciaram a aprendizagem significativa crítica. Realizou-se uma pesquisa qualitativa com cem (100) estudantes, utilizando os seguintes instrumentos de coleta de dados: provas de lápis e papel, autoavaliação, fichas individuais de observações, relatórios e registros pessoais. Apresentam-se os dados organizados em tabelas e gráficos. O processo de ensino-aprendizagem, na perspectiva de Gowin visa compartilhar significados, tendo como protagonistas da ação: o aluno, o professor e os materiais educativos. Foram utilizados vários tipos de atividades: aulas expositivas, aulas práticas usando caderno quadriculado e/ou papel milimetrado e o programa GeoGebra; leitura e discussão dos conteúdos; produção de textos; atividades individuais e em grupo. Os resultados apresentam evidências de que a UEPS foi exitosa. A tese está dividida em cinco capítulos, sendo o primeiro da Revisão da Literatura, o segundo da Fundamentação Teórica, o terceiro os procedimentos metodológicos, o quarto apresenta a Proposta Didática, organizada a partir da elaboração de uma UEPS, no quinto encontram-se os resultados e suas análises fundamentadas na TAS de Ausubel, TASC de Moreira e no modelo triádico de Gowin. Finalizando esse estudo com as perspectivas da utilização deste trabalho para promover aprendizagem significa crítica no ensino de matemática.Las dificultades en la enseñanza y el aprendizaje de las matemáticas constituyen muchas veces un obstáculo para el desarrollo integral de los estudiantes y el pleno ejercicio de la ciudadanía. Se cree que es posible promover el aprendizaje crítico significativo a partir de la aplicación de Unidades de Enseñanza Potencialmente Significativas (UEPS), basadas en los principios de TASC. Esta tesis presenta el análisis de la construcción del concepto de un sistema de ecuaciones de 1° grado con dos variables, aplicando una UEPS, utilizando la estrategia de situaciones problema como metodología didáctica para promover el aprendizaje crítico significativo en el 8° año de la Enseñanza Fundamental del Colegio de Aplicación de la Universidad Federal de Roraima (CAp/UFRR), Brasil. Fue necesario diagnosticar los conocimientos previos de los estudiantes, elaborar, aplicar y evaluar el aporte de la UEPS, analizar el nivel del compartir de significados de los estudiantes en relación al concepto estudiado; verificar cual de los 13 principios de TASC influyó en el aprendizaje crítico significativo. Se realizó una investigación cualitativa con cien (100) estudiantes, utilizando los siguientes instrumentos de recogida de datos: pruebas de lápiz y papel, autoevaluación, fichas de observación individual, informes y fichas personales. Los datos se presentan organizados en tablas y gráficos. El proceso de enseñanza-aprendizaje, en la perspectiva de Gowin, tiene como objetivo compartir significados, teniendo como protagonistas de la acción: el alumno, el docente y los materiales educativos. Se utilizaron varios tipos de actividades: clases expositivas, clases prácticas con cuaderno cuadriculado y/o papel cuadriculado y el programa GeoGebra; lectura y discusión de contenidos; producción de textos; actividades individuales y grupales. Los resultados muestran evidencia de que la UEPS fue exitosa. La tesis se divide en cinco capítulos, el primero sobre la Revisión de la Literatura, el segundo sobre la Fundamentación Teórica, el tercero sobre los procedimientos metodológicos, el cuarto presenta la Propuesta Didáctica, organizada a partir de la elaboración de una UEPS, en el quinto se encuentran los resultados y sus análisis basados en el TAS de Ausubel, el TASC de Moreira y el modelo triádico de Gowin. Terminando este estudio con las perspectivas de utilizar este trabajo para promover el aprendizaje crítico en la enseñanza de las matemáticas.Difficulties in teaching and learning mathematics often constitute an obstacle to the integral development of students and the full exercise of citizenship. It is possible to promote critical meaningful learning from the application of Potentially Meaningful Teaching Unit (PMTU), based on the principles of the Critical Meaningful Learning Theory (CMLT). This thesis presents the concept construction analysis of system of firstdegree equations in two variables, applying a PMTU, using the problem-situation strategy as a teaching methodology to promote critical meaningful learning in the 8th year of Elementary School at Colégio de Aplicação from the Federal University of Roraima (CAp/UFRR), Brazil. It was necessary to diagnose the students' prior knowledge, elaborate, apply and evaluate the contribution of PMTU, analyze the level of sharing of meanings of the students in relation to the studied concept; verify which of the 13 CMLT principles influenced critical meaningful learning. Qualitative research was carried out with one hundred (100) students, using the following data collection instruments: pencil and paper tests, self-assessment, individual observation sheets, reports and personal records. The data are organized in tables and graphs. The teaching-learning process, in Gowin's perspective, aims to share meanings, having as protagonists of the action: the student, the teacher and the educational materials. Several types of activities were used: expository classes, practical classes using squared notebook and/or graph paper and the GeoGebra program; reading and discussion of contents; production of texts; individual and group activities. The results show evidence that the PMTU was successful. The thesis is divided into five chapters, the first on the Literature Review, the second on the Theoretical Foundation, the third on the methodological procedures, the fourth presents the Didactic Proposal, organized from the elaboration of a PMTU, in the fifth are the results and their analysis based on Ausubel's Meaningful Learning Theory (MLT), Moreira's CMLT and Gowin's triadic model. We end this study with the perspectives of using this work to promote critical learning in mathematics teaching
Integrated methodology for sustainability assessment of several innovative materials and processes in different industrial scenarios
No full textLos materiales compuestos de matrices metálicas han atraído gran atención en los últimos años, principalmente por sus mejoradas características mecánicas, en especial su baja proporción en peso, lo que les confiere una gran importancia en determinadas industrias como la aeroespacial o automovilística, entre otras. Sin embargo, y en línea con las actuales tendencias en materia de sostenibilidad y circularidad promovidas por la gran mayoría de políticas internacionales, la preocupación en cuanto a su impacto ambiental ha crecido recientemente debido a la falta de datos y a su gran interrelación con la industria manufacturera. Es por ello que el objetivo de esta tesis doctoral es investigar, mediante la metodología de Análisis de Ciclo de Vida (ACV), las implicaciones medioambientales que tienen el uso de estos materiales en los procesos industriales que los utilizan, aportando nuevos datos que puedan finalmente apoyar la toma de decisiones en el desarrollo y mejora de las tecnologías para lograr un mejor desempeño ambiental. En primer lugar, como primera toma de contacto con la metodología, se analiza la producción de pomos de puerta, mediante dos diferentes técnicas de fundición, formados por una aleación entre aluminio y partículas de dióxido de titanio, que le confiere capacidad auto-limpiable. En la segunda parte se compara un método convencional y otro más novedoso de producción de polvo metálico de titanio para su uso en técnicas de fabricación aditiva, profundizando aún más en la metodología de ACV y en el uso y modificación de bases de datos. Por último, se analiza la utilización del material previo en la producción de una caja de cambios, mediante el uso de una técnica convencional de fundición y otra más novedosa de fabricación aditiva, conocida como deposición de energía dirigida (Direct Energy Deposition o DED). Este caso se trata de un análisis prospectivo en el que se evalúan diferentes escenarios de desarrollo y mejora de la nueva tecnología, escalando los parámetros actuales para encontrar un óptimo en el que poder compararla fielmente con su tecnología de contrapartida, mucho más madura. Se realiza mediante un enfoque paso a paso bajo un análisis ex-ante, aportando como resultado diferentes recomendaciones de ecodiseño para ayuda en la toma de decisiones en la mejora de tecnologías emergentes. Los análisis producidos, los datos extraídos y el modelo final creado para comparar tecnologías maduras y en desarrollo, pueden ser claves para evaluar y cuantificar los impactos ambientales en entornos industriales innovadores, identificando puntos críticos y optimizando así los procesos.Metal Matrix Composites have attracted much attention in recent years, mainly due to their improved mechanical characteristics, in particular their low weight ratio, which makes them of great importance in certain industries such as aerospace or automotive, among others. However, and in line with the current trends in sustainability and circularity promoted by the vast majority of international policies, concern regarding their environmental impact has recently risen due to the lack of data and their strong interrelation with the manufacturing industry. That is why the aim of this doctoral thesis is to investigate, by means of the Life Cycle Assessment (LCA) methodology, the environmental implications of the use of these materials in the industrial processes, providing with new data that can finally support decision-making in the development and improvement of technologies to achieve better environmental performance.He de agradecer la ayuda predoctoral concedida por la Orden EDU/1508/2020 de la Consejería de Educación de la Junta de Castilla y León, cofinanciada por el Fondo Social Europeo, que ha sufragado mi contrato para elaborar esta tesis. También a la Comisión Europea, por financiar el proyecto LightMe (G.A. 814552) enmarcado en el programa Horizonte 2020, y dentro del que se ha desarrollado la presente investigación
Subcritical Water Treatment for Valorization of the Red Algae Residue after Agar Extraction: Scale-Up from Laboratory to Pilot Plant
No full textThe feasibility of industrial subcritical water treatment on Gelidium sesquipedale residue through scaling up from the lab to pilot system in discontinuous mode (geometric scale-up factor = 50), at 130 and 175 °C (5% biomass), was investigated. The maximum volumes of the reactors were 500 mL at the lab-scale and 5 L at the pilot-scale system. At 175 °C, faster extraction/hydrolysis was observed for the pilot plant, but maximum yields were similar: 71.4 and 78.6% for galactans, 9.8 and 10.4% for glucans, and 92.7 and 86.1% for arabinans in pilot scale and lab scale, respectively, while the yields for proteins accounted nearly 40%. The highest yields for amino acids were observed for the smallest ones, while lower yields were determined for polar amino acids. The total phenolic content and color intensity progressively increased along time at lab scale, while a plateau was reached at the pilot level. Lower extraction yields but reproducible results were obtained at 130 °C. Finally, the pilot scale was essayed at a higher biomass loading (15%), and successful results were obtained, supporting the feasibility of the scaling-up process.This work was supported by the Agencia Estatal de Investigación (Spain) [grant numbers PID2019-104950RB-I00/AEI/10.13039/501100011033, TED2021-129311B-I00, and PDC2022-133443-I00], the Junta de Castilla y León (JCyL), and the European Regional Development Fund (ERDF) [grant number BU050P20]. The predoctoral contracts of E.T. and P.A.-R. were funded by the JCyL and ESF [ORDEN EDU/574/2018 and EDU/556/2019, respectively]
Cobres de Flandes en Castilla: los Misterios del Rosario de Otto van Veen del retablo del hospital de Briviesca (Burgos)
No full textDesde los años finales del siglo XVI y sobre todo en el siglo XVII fue muy frecuente en España
la presencia de obras pictóricas flamencas realizadas sobre cobre que pudieron llegar como
consecuencia de importaciones llevadas a cabo por comerciantes que, una vez adquiridos estos
objetos en los territorios de origen, se encargaron de distribuirlos en los mercados españoles y
americanos. Junto a esta manera de importación también fueron muy importantes los encargos
directos, realizados en esas tierras por destacados hombres de la nobleza, el comercio o la Iglesia
a notables artistas, dando lugar a realizaciones que, en muchos casos, acabaron en sus palacios,
casas y fundaciones religiosas en los territorios hispanos. Este segundo grupo de obras suele caracterizarse
por su mayor calidad y singularidad. Este es el caso de los cobres del Rosario, realizados
por Otto van Veen para Juan Fernández de Velasco, VI Condestable de Castilla, pinturas que
pasaron de formar parte de un uso privado a uno público cuando se ensamblaron en el retablo de
la capilla del Rosario del Hospital de Briviesca puesto bajo la protección de este noble castellano
A Systematic Review of Literature on Emerging Technologies and Specific Learning Difficulties
No full textRevisiónEducational research on emerging technologies, particularly virtual reality and augmented
reality, is expanding at the moment. The purpose of this contribution is to conduct a systematic
review to understand the impact of emerging technologies in the educational and social-health
fields. The PRISMA 2020 methodology was used to respond to the objective and research questions,
ensuring the fulfillment of the quality criteria in the elaboration of the systematic review. This
systematic review analyses the possible benefits that new technologies, specifically virtual reality and
augmented reality, can have on learning difficulties such as dyslexia and ADHD disorder, as well
as their inclusion in the social sphere. In this study, articles from both the health and educational
fields will be reviewed. The research focuses on highlighting the incipient benefits of these new
technologies for the aforementioned learning difficulties in the school and health fields. The main
conclusions drawn show that research on these emerging technologies is still scarce and incipient in
the educational field, with the main results found in the healthcare field.This work has been co-financed by the Erasmus + program of the European Union through the 2018-1-ES01-KA201-050659 project. That of the European Commission for the preparation of this publication does not imply acceptance of its contents, which is the sole responsibility of the authors. Therefore, the Commission is not responsible for the use that may be made of the information disclosed here
Optimizing pressurized hot water technology to assist the recovery of residual crude agar from the algae industry waste stream with tailorable physicochemical properties and gel texture
No full textComunicación oral presentada en: The 5th International Symposium on Processing of Food, Vegetables and Fruits (ISPFVF) 2023, durante los días 22-23 de junio en University of Nottingham Malaysia (Malasia).This work was supported by the European Commission, Horizon 2020 program through the Marie-Curie Individual Fellowship (H2020-MSCA-IF-2019), with regards to the ALGWAS-BIOR project (Grant agreementnumber 898804)
Transition probability matrices for pavement deterioration modelling with variable duty cycle times
No full textProbabilistic pavement models, with Markov chains as the most widely used type, are considered to capture an accurate representation of the in situ pavement performance. Homogeneous Markov chain models present the same transition probability matrix (TPM) for all the transitions of the period and require data from multiple duty cycles of one or two years. The aim of this paper is to explore the feasibility of developing homogeneous Markov chain models with variations of the duty cycle (in increments of either one or two years). Without considering maintenance and rehabilitation works, this research found that TPMs for a one-year duty cycle can be calculated from the two-year duty cycle, without a noticeable effect on accuracy using International Roughness Index (IRI) values from the Spanish State Road Network. However, for developing coherent TPMs, two primary assumptions were made: (1) heavy vehicle traffic volumes determine the traffic category (TC), and (2) only roads from the same climatic region were modelled. The satisfactory results verified the validity of the methodology and overcame the disadvantages of homogeneous Markov models. Furthermore, the results suggest that pavement sections are adequately designed in Spain for each TC because of the similar deterioration patterns
Cardiovascular risk factors in alzheimer's disease-a metaanalysis
No full textAD follows a progressive degenerative course characterized by an insidious
progression whose symptomatological manifestations usually appear in a staggered
manner
Molecularly imprinted polypyrrole based electrochemical sensor for selective determination of ethanethiol
No full textThis work describes a molecularly imprinted (MIP) sensor, based on the electropolymerization of pyrrole on a glassy carbon electrode (GCE), for the determination of ethanethiol. Ethanethiol was used as a template molecule for the formation of cavities in the imprinted polymer. The effect of molar ratios template molecules/functional monomers and time needed to remove the template were optimized. The developed MIP/GCE sensor presented a linear range from 6.1 to 32.4 mg L−1 with capability detection and reproducibility values of 7.2 mg L−1 and 10.4%, respectively. The sensitivity of the developed sensor was enhanced by the incorporation of gold nanoparticles (AuNPs). The AuNPs/MIP/GCE showed a capability of detection and reproducibility values of 0.4 mg L−1 and 4.1%, respectively (calibration range from 0.3 to 3.1 mg L−1). The sensor was successfully applied to the determination of ethanethiol in spiked wine samples with recoveries ranging from 99% to 107%.Authors would like to acknowledge funding obtained by Junta de Castilla y León (BU018G19) and Agencia Estatal de Investigación (PID2020-117095RB-I00)