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Shannon information entropy for a quantum nonlinear oscillator on a space of non-constant curvature
Get PDFThe so-called Darboux III oscillator is an exactly solvable N-dimensional nonlinear oscillator defined
on a radially symmetric space with non-constant negative curvature. This oscillator can be interpreted
as a smooth (super)integrable deformation of the usual N-dimensional harmonic oscillator in terms of
a non-negative parameter λ which is directly related to the curvature of the underlying space. In this
paper, a detailed study of the Shannon information entropy for the quantum version of the Darboux
III oscillator is presented, and the interplay between entropy and curvature is analysed. In particular,
analytical results for the Shannon entropy in the position space can be found in the N-dimensional case,
and the known results for the quantum states of the N-dimensional harmonic oscillator are recovered
in the limit of vanishing curvature λ → 0. However, the Fourier transform of the Darboux III wave
functions cannot be computed in exact form, thus preventing the analytical study of the information
entropy in momentum space. Nevertheless, we have computed the latter numerically both in the one
and three-dimensional cases and we have found that by increasing the absolute value of the negative
curvature (through a larger λ parameter) the information entropy in position space increases, while in
momentum space it becomes smaller. This result is indeed consistent with the spreading properties
of the wave functions of this quantum nonlinear oscillator, which are explicitly shown. The sum of
the entropies in position and momentum spaces has been also analysed in terms of the curvature: for
all excited states such total entropy decreases with λ, but for the ground state the total entropy is
minimized when λ vanishes, and the corresponding uncertainty relation is always fulfilled.This work has been partially supported by Agencia Estatal de Investigación (Spain) under grant PID2019-106802GB-I00/AEI/ 10.13039/501100011033, by the Regional Government of Castilla y León (Junta de Castilla y León, Spain) and by the Spanish Ministry of Science and Innovation MICIN and the European Union NextGenerationEU/PRTR, as well as the contribution of the European Cooperation in Science and Technology through the COST Action CA18108. The authors acknowledge A. Najafizade for useful discussions at the early stages of this work, and also the Referee for several relevant comments and suggestions
Multi-parametric flowability classification of self-compacting concrete containing sustainable raw materials: An approach to real applications
Get PDFAdding sustainable raw materials to Self-Compacting Concrete (SCC) modifies its flowability
behavior. Furthermore, the use of these raw materials may at the same time even improve one
fresh property while worsening another. An accurate flowability description of SCC containing
sustainable raw materials therefore requires a multi-parametric classification that simultaneously
covers all fresh properties (slump flow, viscosity, and blocking ratio) for an accurate description
of its potential applications. Existing classifications consider each fresh property independently.
In this paper, a multi-parametric flowability classification of SCC containing sustainable raw
materials is proposed. The effects of multiple sustainable raw materials on SCC flowability are
compiled in a dataset serving as a knowledge base with information on 663 SCC mixes containing
sustainable aggregates and binders. The statistical analysis of the dataset led to the definition of
three types of flowability zones. Firstly, the overall-flowability zones, in which SCC flowability is
described in absolute terms: the better the in-fresh properties, the better the overall-flowability
zone. Secondly, the flowability-balance zones reflect the balance between free flow (slump
flow and slump-flow viscosity) and flow around obstacles (V-funnel emptying time and L-box
blocking ratio). Finally, SCC is classified within flowability-predominance zones, which define the
main characteristic of SCC flowability, rate of flow (viscosity) or uniformity of flow (spreading).
The variability of the effect of each sustainable raw material on the flowability of SCC makes this
classification useful, in so far as it offers a complete picture of the fresh behavior of SCC in which
all fresh properties are simultaneously considered. Furthermore, based on the description in the
proposed classification of overall flowability and the balance between free flow and flow around
obstacles, the application fields are defined for which the use of each SCC mix with sustainable
raw materials is recommended.This research work was supported by the Spanish Ministry of Universities, MICINN, AEI, EU, ERDF and NextGenerationEU/PRTR [grant numbers PID2020-113837RB-I00; 10.13039/501100011033; TED2021-129715B–I00; FPU17/03374]; the Junta de Castilla y León (Regional Government) and ERDF [grant number UIC-231]; and, finally, the University of Burgos [grant number SUCONS, Y135. GI]
New record of cold-adapted fauna on the Castilian Plateau: Woolly rhinoceros – Coelodonta antiquitatis (Blumenbach, 1799) – at La Mina (Burgos, Spain)
No full textLa Mina is one of three sites, along with Cueva Millán and La Ermita, located in the middle course of the Arlanza river. La Mina was excavated for the first time in 2006 and three test pits were carried out. In one of them, evidence of two Palaeolithic occupations was identified and several remains of woolly rhinoceros were recovered. Amino acid racemisation dating yielded an age of 52.5 ka BP, the earliest Upper Pleistocene date for Coelodonta antiquitatis on the Iberian Peninsula. This new record may have several implications for understanding the access routes to the Castilian Plateau, together with the definition of a new migratory wave of this species at the end of the Pleistocene. The location of La Mina on the Castilian Plateau may help researchers to complete the movements of this species through the Middle and Upper Palaeolithic on the Iberian Peninsula.Our study was supported by Project CGL2006-13532-C03/BTE ‘Gestión del territorio en el Paleolítico medio del área centroriental de Castilla y León por medio del estudio de fuentes y productos líticos’ funded by the Consejería de Educación de la Junta de Castilla y León
Diseño de un programa de atención plena basado en la revisión sistemática de técnicas de mindfulness en la discapacidad intelectual y las dificultades específicas de aprendizaje
Get PDFEl presente trabajo se ha centrado en el desarrollo de un programa de atención plena dirigido a alumnos con discapacidad intelectual y/o dificultades específicas de aprendizaje. Con el fin de diseñarlo se ha realizado una revisión sistemática de investigaciones basadas en mindfulness, tema de actualidad en el ámbito educativo. Se ha utilizado la metodología PRISMA 2020 para responder a los objetivos de la investigación. En la revisión se han analizado los posibles beneficios que mindfulness puede aportar a la discapacidad intelectual y las dificultades específicas de aprendizaje, así como los principales contenidos de los programas y su impacto en el bienestar de los alumnos. Las principales conclusiones extraídas muestran una mayoría de actividades enfocadas en la respiración consciente y el escáner corporal como estrategias para reducir la ansiedad, el estrés y los síntomas de depresión.This paper has focused on the development of a mindfulness programme aimed at students with intellectual disabilities and/or specific learning difficulties. In order to design it, a systematic review of research based on mindfulness, which is topical in the field of education, has been carried out. The PRISMA 2020 methodology has been used to respond to the research objectives. The review analysed the possible benefits that mindfulness can bring to intellectual disabilities and specific learning difficulties, as well as the main contents of the programmes and their impact on the well-being of students. The main conclusions drawn show a majority of activities focused on mindful breathing and body scanning as strategies to reduce anxiety, stress and depressive symptoms
Extracción de ácido cítrico mediante tecnologías limpias
No full textEl ácido cítrico es uno de los ácidos orgánicos más utilizados en la industria alimentaria, ya
que se considera un aditivo seguro. Generalmente se produce mediante procesos de
fermentación, siendo necesarias varias etapas de postratamiento muy costosas para su
recuperación y purificación. En los últimos años se está investigando el uso de tecnologías
limpias como alternativas para la recuperación de ácido cítrico de una forma más económica
y ambientalmente sostenible. Este trabajo tiene como objetivo principal evaluar la viabilidad
técnica de un proceso combinado de extracción de ácido cítrico de disoluciones acuosas
diluidas utilizando niosomas y la concentración de los mismos de forma simultánea mediante
microfiltración, estando ambas consideradas como tecnologías limpias. Se formularon
niosomas formados por los tensioactivos Span 80 (20 mM) y SDS (4 mM) mediante
ultrasonicación y se utilizó una membrana cerámica tubular de TiO2 de 0,2 µm de tamaño de
poro para separar y concentrar mediante microfiltración los niosomas con el ácido cítrico
extraído.
En primer lugar, se realizaron 3 experimentos de extracción en 1 etapa utilizando diferentes
concentraciones de ácido cítrico (5, 10 y 20 mM) en la alimentación (400 mL) y el mismo
volumen de fase dispersa de niosomas (30 mL), bajo las mismas condiciones de temperatura
(20 ºC) y presión transmembrana (0,3 bar). En todos los casos se alcanzó el equilibrio de
extracción para tiempos comprendidos entre 22 y 30 minutos, con un buen ajuste de los datos
experimentales al modelo teórico propuesto y buenas densidades de flujo de permeado (J =
50–70 L/m2 h). Los mejores resultados, con un 20,03% de extracción de ácido cítrico, se
obtuvieron para la alimentación con la mayor concentración inicial de ácido (20 mM).
Finalmente se llevó a cabo un experimento de extracción de ácido cítrico en 2 etapas en serie,
utilizando 400 mL de la disolución de ácido cítrico 20 mM como alimentación para la etapa 1,
y el permeado de la etapa 1 como alimentación de la etapa 2, obteniendo un grado de
extracción del 38,17% de ácido cítrico para el proceso global.
El desarrollo y uso de tecnologías limpias como las utilizadas en este trabajo contribuiría a
lograr alguna de las metas de los objetivos de desarrollo sostenible (ODS), concretamente del
ODS 9: Industria, innovación e infraestructuras, e indirectamente también del ODS 6: Agua
limpia y saneamiento.Citric acid is one of the most widely used organic acids in the food industry, as it is considered
a generally recognized as safe (GRAS) additive. It is generally produced by fermentation
processes, requiring several and very expensive post-treatment stages for its recovery and
purification. In recent years, the use of clean technologies has been investigated as
alternatives for the recovery of citric acid in a more economical and environmentally
sustainable way. The main objective of this work is to evaluate the technical feasibility of a
combined process for the extraction of citric acid from dilute aqueous solutions using niosomes
and their concentration simultaneously by microfiltration, both being considered as clean
technologies. Niosomes of Span 80 (20 mM) and SDS (4 mM) surfactants were formulated by
ultrasonication, and a 0.2 µm pore size TiO2 tubular ceramic membrane was used to separate
and concentrate the niosomes with the extracted citric acid by microfiltration.
Three 1-stage extraction experiments were first performed using different concentrations of
citric acid (5, 10 and 20 mM) in the feed (400 mL) and the same volume of dispersed phase of niosomes (30 mL), under the same temperature (20 ºC) and transmembrane pressure (0.3
bar) operating conditions. Extraction equilibrium was reached for times between 22 and 30
minutes in all cases, with good adjustment of the experimental data to the proposed theoretical
model and good permeate flux values (J = 50–70 L/m2 h). Best results, with 20.03% citric acid
extraction, were obtained for the feed with the highest initial acid concentration (20 mM).
Finally, a 2-stage citric acid extraction experiment was performed, using 400 mL of the 20 mM
citric acid solution as feed for stage 1, and the permeate from stage 1 as feed for stage 2,
obtaining a citric acid extraction degree of 38.17% for the global process.
The development and use of clean technologies such as those tested in this work would
contribute to achieving some of the objectives of the sustainable development goals (SDG),
specifically SDG 9: Industry, innovation and infrastructure, and indirectly also SDG 6: Clean
water and sanitation.Este Trabajo Fin de Grado ha sido realizado en el marco de los siguientes proyectos de
investigación del grupo Biotecnología Industrial y Medioambiental (BIOIND) de la Universidad
de Burgos:
PID2019-104950RB-I00 – Valorización de subproductos marinos mediante tecnologías de
fluidos sub- y supercríticos para la obtención de biocompuestos valiosos, financiado por la
Agencia Estatal de Investigación.
BU050P20 – Valorización de la fracción proteica de subproductos de la industria
agroalimentaria de Castilla y León mediante tecnologías de fluidos presurizados, financiado
por la Junta de Castilla y León y el Fondo Europeo de Desarrollo Regional (FEDER).
PID2020-116716RJ-I00 – Tecnologías de fluidos presurizados para la valorización de
subproductos de la industria agroalimentaria: recuperación de pectina y otros compuestos
bioactivos de alto valor, financiado por la Agencia Estatal de Investigación.
TED2021-129311B-I00 – Tecnologías verdes basadas en el empleo de fluidos presurizados
para valorizar biomasa lignocelulósica mediante la producción de furfural, financiado por el
Ministerio de Ciencia e Innovación.
PDC2022-133443-I00 – Diseño de un prototipo para la extracción de bioproductos con agua
subcrítica, financiado por el Ministerio de Ciencia e Innovación
Biomarkers of Oxidative Stress in Healthy Infants within the First Three Days after Birth
No full textThe clinical relevance of stress biomarkers in newborns is well established. Currently,
oxidative stress (OS) parameters are seen to play an important role in neonatal resuscitation guidelines,
and a link has been observed between the amount of oxygen delivered and the level of OS and the
development of various pathologies. The aim of the current study was to investigate changes in
neonatal plasma and urine OS status during the first hours after birth. A lower antioxidant capacity
(TAC) and higher levels of malondialdehyde in blood were observed in newborns at the time of
birth compared with results 48 h postnatally. The urine revealed a significant and progressive
increase in TAC and creatinine during the first 36 h of life, with a progressive decline thereafter.
Meanwhile, malondialdehyde in urine samples showed no significant differences over time. Overall,
the correlation between blood and urine parameters was poor, except for the relationship between
umbilical vein glutathione reduced/oxidized ratio and urine malondialdehyde (r = 0.7; p = 0.004)
and between TAC in the umbilical artery and urine (r = −0.547; p = 0.013). The biomarkers evaluated
in this study could be established as reference values for neonatal OS.This research was funded by Fundación Burgos por la Investigación de la Salud (grant number 1088) and Gerencia Regional de Castilla y Leon (grant number GRS 1773/A/18)