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Analyzing Dropout in Alcohol Recovery Programs: A Machine Learning Approach
Get PDFBackground: Retention in treatment is crucial for the success of interventions targeting
alcohol use disorder (AUD), which affects over 100 million people globally. Most previous studies
have used classical statistical techniques to predict treatment dropout, and their results remain
inconclusive. This study aimed to use novel machine learning tools to identify models that predict
dropout with greater precision, enabling the development of better retention strategies for those
at higher risk. Methods: A retrospective observational study of 39,030 (17.3% female) participants
enrolled in outpatient-based treatment for alcohol use disorder in a state-wide public treatment
network has been used. Participants were recruited between 1 January 2015 and 31 December 2019.
We applied different machine learning algorithms to create models that allow one to predict the
premature cessation of treatment (dropout). With the objective of increasing the explainability of
those models with the best precision, considered as black-box models, explainability technique
analyses were also applied. Results: Considering as the best models those obtained with one of
the so-called black-box models (support vector classifier (SVC)), the results from the best model,
from the explainability perspective, showed that the variables that showed greater explanatory
capacity for treatment dropout are previous drug use as well as psychiatric comorbidity. Among
these variables, those of having undergone previous opioid substitution treatment and receiving
coordinated psychiatric care in mental health services showed the greatest capacity for predicting
dropout. Conclusions: By using novel machine learning techniques on a large representative sample
of patients enrolled in alcohol use disorder treatment, we have identified several machine learning
models that help in predicting a higher risk of treatment dropout. Previous treatment for other
substance use disorders (SUDs) and concurrent psychiatric comorbidity were the best predictors
of dropout, and patients showing these characteristics may need more intensive or complementary
interventions to benefit from treatment.This study was supported by the grant “COMPARA: Comorbilidad Psiquiátrica en Adicciones
y Resultados en Andalucía. Modelización a través de Big Data”, project P20_00735 in the
Andalusian Research, Development, and Innovation Plan, provided by the Fondo Europeo de Desarrollo
Regional (EU) and Junta de Andalucía (Spain).Departamento de Psicología Clínica, Experimental y Socia
New SiS destruction and formation routes via neutral-neutral reactions and their fundamental role in interstellar clouds at low- and high-metallicity values
Get PDFContext. Among the silicon-bearing species discovered in the interstellar medium, SiS and SiO stand out as key tracers due to their distinct chemistry and variable abundances in interstellar and circumstellar environments. Nevertheless, while the origins of SiO are well documented, the SiS chemistry remains relatively unexplored.
Aims. Our objective is to enhance the network of Si- and S-bearing chemical reactions for a gas-grain model in molecular clouds, encompassing both low and high metallicities. To achieve this, we calculated the energies and rate coefficients for six neutral atom-diatom reactions involved in the SiCS triatomic system, with a special focus on the C+SiS and S+SiC collisions.
Methods. We employed the coupled-cluster method with single and double substitutions and a perturbative treatment of triple substitutions (CCSD(T)) refined at the explicitly correlated CCSD(T)-F12 level. With these computational results in conjunction with supplementary data from the literature, we construct an extended network of neutral-neutral chemical reactions involving Si- and S-bearing molecules. To assess the impact of these chemical reactions, we performed time-dependent models employing the Nautilus gas-grain code, setting the gas temperature to 10 K and the H2 density to 2 × 10^4 cm−3 . The models considered two initial abundance scenarios, corresponding to low- and high-metallicity levels. Abundances were computed using both the default chemical network and the constrained network, enriched with newly calculated reactions.
Results. The temperature dependence for the reactions involving SiS were modelled to the k(T ) = α (T/300)β exp (−γ/T ) expression, and the coefficients are provided for the first time. The high-metallicity models significantly boost the SiS production, resulting in abundances nearly four orders of magnitude higher compared to low-metallicity models. Higher initial abundances of C, S, and Si, roughly ∼2, 190, and 210 times higher, respectively, contribute to this. Around the age of 10^3 yr, destruction mechanisms become relevant, impacting the abundance of SiS. The proposed production reaction S + SiC −→ C + SiS, mitigates these effects in later stages. By expanding the gas reaction network using a high-metallicity model, we derived estimates for the abundances of observed interstellar molecules, including SiO, SO, and SO2 .
Conclusions. We demonstrate the significance of both SiC+S and C+SiS channels in the SiS chemistry. Notably, the inclusion of neutral-neutral mechanisms, particularly via Si+HS and S+SiC channels, played a pivotal role in determining SiS abundance. These mechanisms carry a significance level on a par with that of the well-known and fast ion-neutral reactions
Assessing citizen science data quality for bird monitoring in the Iberian Peninsula
Get PDFCitizen science data on biodiversity has experienced signifcant growth, largely driven by
advancements in technology that facilitate data sharing. In recent years, mobile applications have
provided a substantial boost to both the collection and sharing of this data. While this accessible
information is undoubtedly valuable, we must consider the numerous biases present in this data when
used for high-quality research. In this study, we analyse citizen science data for the birds of the Iberian
Peninsula, comprising over 23 million unique records after fltering for duplicates (i.e., instances where
the same observation was uploaded more than once). Using a 10 × 10 km square grid, we present
information on well-surveyed cells (completeness) as well as temporal, taxonomic, geographical, and
land use coverages. We found that the completeness of information is generally high, with better
coverage around densely populated areas such as major cities and coastal regions, as well as popular
birding destinations, which are frequently visited. The Mediterranean ecoregion and wetlands exhibit
the highest levels of surveying. Furthermore, we observed an increase in temporal coverage since
the 1980s and broad taxonomic coverage across all bird orders in the Iberian region. Our results
underscore the utility of citizen science for many locations, as expressed in 10 × 10 km cells. However,
they also highlight the inadequate data completeness across part of the territory, particularly in
forested or sparsely inhabited areas. These fndings not only identify cells suitable for bird diversity
or conservation studies but also indicate areas where citizen-driven bird recording eforts should be
encouragedTis work was fnancially supported by the following three projects: (1) “Agricultura y conservación de la avifauna esteparia en Andalucía. Evaluación de la biodiversidad a partir de conocimiento accesible digital (DAK)
y estudios in situ” (Andalusian Research Plan 2014–2020. Ref. P20_00354) (Operative FEDER Program); (2)
“Procesos de extinción en paisajes agrarios mediterráneos: evaluación de biodiversidad al inicio de una nueva
Política Agraria Común mediante conocimiento accesible digital (DAK) y estudios in situ” (Ref. UHU-202076)
(Operative FEDER Program) and (3) “Infuencia sobre la avifauna del uso y ocupación del territorio en el medio
agrario andaluz por plantas fotovoltaicas y olivar intensivo y superintensivo” (BIOD22_00033_15_PPCB. Plan
Complementario de I+D+i de Biodiversidad). Gross data for this study were provided by GBIF, eBird, and
Observation.org. We extend special gratitude to Julio Rabadán from Observation.org for his invaluable suppor
The narrative and teaching identity: an evaluation of primary education students' perception on the use of videopresentations and life boxes
Get PDFLas videopresentaciones son una herramienta importante para narrar y comunicar dentro de la Educación Superior, convirtiéndola en una técnica que brinda numerosas oportunidades junto con las historias de vida, por su carácter narrativo. El empleo de esta herrammienta en la exposición comunicativa de la caja de vida se convierte en un elemento de gran utilidad en la formación inicial del profesorado, potenciando la adquisición de diferentes competencias de la profesión docente. Esta experiencia se plantea mediante un estudio de caso con un enfoque metodológico mixto y en el que participan dos asignaturas de forma coordinada. Los resultados muestran cómo las y los estudiantes incrementan su motivación, aprenden significativamente, adquieren competencias digitales e inician la construcción de su identidad docente. Finalmente, el trabajo demuestra la importancia de la narrativa y el poder del contenido audiovisual para mejorar las relaciones personales y la relación con conceptos vitales como el tipo de docente que quieren ser. En este campo no existen trabajos o publicaciones sobre experiencias parecidas, siendo una experiencia novedosa en el campo y dentro del propio grupo clase. Por tanto, el estudio presentado tiene el objetivo de analizar el grado de satisfacción en el alumnado que cursa el primer curso del Grado de Educación Primaria, tras realizar una actividad que combina la creación de una videopresentación con la construcción de una caja de vida personalVideo presentations are an important tool for narrating and communicating within higher education, making it a technique that offers numerous opportunities in conjunction with life stories due to its narrative nature. The use of video presentations in communicative exposition of the life box becomes a highly useful element in teacher's initial training, enhancing the acquisition of different teaching competencies. In this field, there are no works or publications on similar experiences, making it a novel experience in the field and within the class group itself. Therefore, the presented study aims to analyze the degree of satisfaction in students enrolled in the first year of the Primary Education Degree, after carrying out an activity that combines the creation of a video presentation with the construction of a personal life box. This experience is approached through a case study with a mixed methodological approach in which two subjects participate in a coordinated manner. The results show how students increase their motivation, learn significantly, acquire digital competencies, and initiate the construction of their teaching identity. Finally, the work demonstrates the importance of narrative and the power of audiovisual content to improve personal relationships and the relationship with vital concepts such as the type of teacher they want to b
The Space for Religion and Spirituality in Business, Management, and Entrepreneurship Education: Reflections on the Main Contributions and Tentative Directions
Get PDFThe business, management, and entrepreneurship (BME) education provided by universities is believed to influence the way in which organisations are managed in the business world. In recent decades, it has been criticised for its focus on profit and short-term goals, while new approaches inspired by the humanities, particularly religious and spiritual traditions, have been proposed. Although research in this area is growing, it is scattered. In this study, we systematically review the existing literature to deepen our understanding of this emergent stream of research. From a sample of 216 papers, 51 articles from 1996 to 2023, selected from the Web of Science and Scopus databases, are analysed. Overall, the findings highlight that the literature on this topic is predominantly theoretical and suggest that some of the wisdom embedded in religion and spirituality might be considered to inform different discussions in BME courses, with a prominent application of sacred and ancient texts in the teaching of business ethics. Future research avenues are discussed in relation to a variety of themes and pedagogical and empirical approaches that can benefit scholars and advance this area of study.Funding for Open Access charge: Universidad de Huelva /CBU
Effect of acid mine drainage on the mechanical properties of AISI 1020 carbon steel and AW6060 aluminium
Get PDFAcid mine drainage severely affects metallic materials due to the high acidity and oxidising capacity of these
lixiviates. A study was carried out to evaluate the time evolution of the mechanical properties of AISI 1020
carbon steel and AW6060 aluminium in contact with acid mine drainage. Weight loss, fatigue and tensile
strength were evaluated in two different scenarios, one involving erosion corrosion (dynamic scenario) and the
other involving chemical corrosion only (static scenario). Over 80 days of exposure in a static scenario, weight
loss is almost 2% for aluminium and 0.5% for steel, fatigue strength is reduced by 28% for steel and ultimate
tensile strength is reduced by almost 5% for aluminium and by 2.5% for steel. In a dynamic scenario, the weight
loss after 4 days of exposure is 30–35% for both materials, the fatigue strength is reduced by almost 50% for
steel, the ultimate tensile strength is reduced by 33% for aluminium and by almost 5% for steel. Acid drainage
causes an increase in brittleness and a decrease in stiffness of these materials, much more rapidly in a dynamic
environment favoured by the effects of erosion corrosion.CIN/AEI/10.13039/501100011033/FEDER, UE, throughout the project PID2021-123130OB-I00
Tectonic evolution around the Sierra de Arcos thrust (Ariño, northeaster Iberian Chain)
Get PDFEl área de Ariño (Rama Aragonesa de la Cordillera Ibérica, borde
norte de la cuenca de Oliete) muestra un conjunto de macroestructuras
que resultan de la evolución tectónica de la misma: pliegues
con orientación variada (NNO-SSE, E-O y NO-SE), fallas normales
conjugadas, y un cabalgamiento plurikilométrico (cabalgamiento de
la Sierra de Arcos) enraizado en las evaporitas del Triásico superior.
El análisis de estas estructuras permite proponer dos hipótesis acerca
de la evolución tectónica de este sector de la Cordillera Ibérica. La
primera versa sobre la existencia de varios episodios compresivos
de distinta orientación en sus ejes de esfuerzo, que generaron las
estructuras tectónicas presentes en la zona de estudio en el contexto
de la Orogenia Alpina. La segunda se centra en la existencia de un
solo campo de esfuerzos, de orientación N-NNE, y la anisotropía en
la orientación de sus elementos, fruto de la presencia de estructuras
de origen extensional cretácicas relacionadas con fallas de zócaloThe Ariño sector of the Aragonese Branch of the Iberian Chain
(Oliete basin) shows a set of macrostructures resulting from its tectonic
evolution: NNW-SSE, E-W and NW-SE trending folds, and a
plurikilometricthrust (Sierra de Arcos thrust) detached on the Upper
Triassic evaporites. Mesostrutures include normal faults forming
conjugate systems, stylolytic peaks with two main preferred directions
and cleavage planes associated with normal and overturned
limbs in the Upper Triassic. The analysis of these structures allows
to propose two different hypotheses about the tectonic evolution of
this sector of the Iberian Chain during the Cenozoic. The first one
deals with several compressional episodes with differently oriented
stress axis that generated the tectonic structures present in the study
arena. The second one is focused in the interpretation of an only
N-NNE oriented compression, the different orientation of the structures
found resulting from the orientation anisotropy of structural
features, resulting from the previous basinal evolution of the are
Validación de una escala sobre las percepciones del impacto socioeconómico del turismo deportivo de naturaleza
Get PDFThe impact that tourists have on the destination community
modifies their behavior and can be a key factor
guiding both their perceptions and their intention to
revisit the destination. However, the perceptions of tourists
have been little analyzed in the scientific literature.
The objective of this study is to explore the psychometric
properties and validity of a questionnaire aimed at
assessing tourists’ perceptions of the socioeconomic impact
of sports activities in the natural environment. The
sample consisted of 1184 sports tourists who traveled to
the Valle del Jerte (Extremadura, Spain). Both an exploratory
factor analysis and a confirmatory factor analysis
were carried out, as well as an analysis of the reliability of
the instrument. The results showed a final structure of 8
items divided into two factors with satisfactory reliability
values and indicators of the goodness of fit. Therefore,
this research provides a quick, free and easy-to-use tool
to assess the perceptions of sports tourists about the
socio-economic impact generated by the activities they
practice.El impacto que los turistas tienen en la comunidad del
destino modifica su comportamiento y puede ser un
factor clave que guíe tanto sus percepciones como su
intención de volver a visitar el destino. Sin embargo, las
percepciones de los turistas han sido poco analizadas en
la literatura científica. El objetivo de este estudio es explorar
las propiedades psicométricas y la validez de un
cuestionario destinado a evaluar las percepciones de los
turistas sobre el impacto socioeconómico de las actividades
deportivas en el medio natural. La muestra estuvo
formada por 1184 turistas deportivos que viajaron al Valle
del Jerte (Extremadura, España). Se realizó un análisis
factorial exploratorio y un análisis factorial confirmatorio,
así como un análisis de fiabilidad del instrumento. Los
resultados mostraron una estructura final de 8 ítems divididos
en dos factores con satisfactorios valores de fiabilidad
e indicadores de la bondad del ajuste. Por lo tanto,
esta investigación proporciona una herramienta rápida,
gratuita y fácil de usar para evaluar las percepciones de
los turistas deportivos sobre el impacto socioeconómico
generado por las actividades que practican
Milling amorphous FeSiB ribbons with vibratory ball and disc mills
Get PDFFe, Si and B powders, mixed with atomic composition Fe78Si9B13, are subjected after arc melting to a melt spinning process, which is optimized to obtain the greatest amount of amorphous ribbon. The amorphous ribbons are milled to powder form in a vibratory ball mill and a vibratory disc mill, taking care of maintaining the amorphous character. Ribbons and powders have been characterized by X-ray diffraction (XRD), laser diffrac- tion, SEM and TEM microscopy, and differential scanning calorimetry (DSC). The amorphous character and particle size of the powders are characterized as a function of the mill charge and the milling time. It is shown that the use of the ball mill is appropriate for obtaining small quantities of amorphous or nanocrystalline powder, while the disc mill can process larger quantities of powder in a shorter time. The particle sizes obtained for milling times between 10 and 150 min range between 26 and 412 μm, ready for use in powder metallurgy processes.This research was funded by Ministerio de Economía y Competitividad (Spain) and Feder (EU) through the research project
PID2021-123750-OB-I00, and research support conceded by the University of Huelva. Funding for open access charge: Universidad de Huelva / CBUAIngeniería Química, Química Física y Ciencias de los Materiale
Physical profile, nutritional status and effect of relative age of youth basketball players from 9 to 16 years old, related to sports performance in the Costa Rican Minor League
Get PDFEl efecto de la edad relativa (RAE) hace referencia a las
consecuencias en el rendimiento deportivo, gracias a las
diferencias físicas y psicológicas que pueden existir entre
los nacidos en los primeros meses del año y los jugadores
del mismo año. Objetivo: determinar la relación del
perfil físico, el estado nutricional y el efecto de la edad
relativa de los jugadores de baloncesto juveniles de 9
a 16 años, con el rendimiento deportivo mostrado. Metodología:
Se realizó un estudio no experimental, correlacionando
las variables medidas a la muestra de 1302
sujetos participantes del torneo nacional. Resultados: Se
encontró diferencias de rendimiento en categorías U12
femenino con base al mes de nacimiento (rho= -,323;
p =,027), siendo las nacidas en las primeras etapas del
año quienes tienen mayor ventaja deportiva, también se
evidenció efecto del RAE en la categoría U14 masculino,
para el resto de categorías no existe relación, si se observa
como la talla y el peso influyen en una especialización
temprana. Conclusiones: Se determina para la categoría
U12 femenino y U14 masculino que existe una relación
directamente proporcional entre el perfil físico, el estado
nutricional y el efecto de la edad relativa de los jugadores,
con el rendimiento deportivo mostrado en el Torneo
Nacional de Liga Menor 2023 de la Federación Costarricense
de Baloncesto, en las otras categorías no existe
esta relación con el RAE.The relative age effect (RAE) refers to the consequences
on sports performance, thanks to the physical and
psychological differences that may exist between those
born in the first months of the year and players of the
same year. Objective: to determine the relationship of
the physical profile, nutritional status and the effect of relative
age of youth basketball players from 9 to 16 years
old, with the sports performance shown. Methodology: A
non-experimental study was carried out, correlating the
variables measured to the sample of 1302 subjects national
tournament participants. Results: Differences in performance
were found in female U12 categories based on
the month of birth (rho= -.323; p =.027), with those born
in the first stages of the year having the greatest sporting
advantage, an effect was also evident of the RAE in the
U14 male category, for the rest of the categories there is
no relationship, if it is observed how height and weight
influence early specialization. Conclusions: It is determined
for the U12 female and U14 male category that there
is a directly proportional relationship between the physical
profile, nutritional status and the effect of the relative
age of the players, with the sporting performance shown
in the 2023 National Minor League Tournament of the
Costa Rican Basketball Federation, in the other categories
this relationship with the RAE does not exist