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Systematic reduction of the proton-removal cross section in neutron-rich medium-mass nuclei
No full textSingle-neutron and single-proton removal cross sections have been measured for medium-mass neutron- rich nuclei around Z = 50 and energies around 1000A MeV using the FRagment Separator (FRS) at GSI. The measured cross sections confirm the relative low values of the proton-removal cross sections, observed since a long time ago and not yet understood. Model calculations considering the knock- out process together with initial- and final-state interactions describe the measured neutron-removal cross sections. Proton-removal cross sections are, however, significantly over-predicted by the same calculations. The observed difference can be explained to a large extent by the knock-out of short-range correlated nucleons from dominant neutron-proton pairs in neutron-rich nuclei.Agencia Estatal de Investigación | Ref. FPA2015-69640-C2-1-PAgencia Estatal de Investigación | Ref. RTI2018-101578-B-C21Xunta de Galicia | Ref. ED431C 2017/54Xunta de Galicia | Ref. ED481B-2017/002Departamento de Energía de los Estados Unidos (DOE) | Ref. DE-FG02-08ER4153
Experimental research on the countercurrent fixed-bed combustion of biomass
No full textFixed-bed combustion is the oldest and most flexible method for generating heat from solid fuels with diverse morphological characteristics. This approach consolidates countercurrent fixed-bed burners as the most employed technique for biomass combustion in small- and medium-scale installations. In recent decades, researchers worldwide have generated significant experimental evidence to decipher the complex mechanisms behind reaction front propagation using laboratory-scale burners, which simulate the conditions of fuel in industrial plants. Many experimental results are available in the scientific literature, and the consolidation and discussion of the most relevant data can be useful for better understanding the current state of the art and identifying knowledge gaps on the subject. This paper presents a systematic review of the available literature concerning experimental studies of biomass fixed-bed combustion in laboratory-scale reactors. The central discussion encompasses the definition of the parameters employed to characterize the reaction zone behaviour and their dependence on fuel properties and primary air conditions. The insights gained in this review were addressed to propose criteria for harnessing the abundant availability of agricultural residues as alternative fuels in grate-firing systems.São Paulo Research Foundation (FAPESP) | Ref. 2019/07764-2Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Possible potentiating effects of combined administration of alcohol, caffeine, and nicotine on in vivo dopamine release in addiction-related circuits within the CNS of rats
No full textBackground: Studies that assess the effects of the interaction of psychoactive substances on dopamine release, the key neurotransmitter in the neurochemical and behavioral effects related to drug consumption, are crucial to understand both their roles and the dysfunctions they produce in the central nervous system. Objective: We evaluated the effects of individual and combined administration of the three most widely consumed psychoactive substances in the world, ethanol, caffeine, and nicotine, on dopaminergic neurotransmission in three brain regions of rats related to addiction: the prefrontal cortex (PFC), the nucleus accumbens (NAcc), and the dorsal striatum. Methods: The dopamine levels were measured in vivo by cerebral microdialysis associated with HPLC-ED. Results: We observed that local administration of a single concentration of caffeine (5 mM) or nicotine (5 mM) significantly increased the dopamine levels in all three areas studied, while ethanol (300 mM) increased them in the NAcc and striatum. Perfusion of nicotine + caffeine produced a synergistic effect in both the NAcc and striatum, with increases in the in vivo dopamine release greater than the sum of the effects of both substances. When administering the combination of nicotine + caffeine + ethanol, we observed an additive effect in the NAcc, while in the PFC we observed a synergistic effect. Conclusions: Our results support the stimulating effects of caffeine, nicotine, and ethanol on the brain reward system. In addition, we also observed that the administration of different mixtures of these substances produces synergistic and additive effects on the release of dopamine in the mesocortical and nigrostriatal systems.Xunta de Galicia | Ref. C18-GPC-2019Universidade de Vigo/CISUGUniversidade de Vig
Resource interoperability: Exploiting lexicographic data to automatically generate dictionary examples
No full textThis paper describes the different design and development stages of the MultiGenera and MultiComb prototypes for the multilingual automatic generation of dictionary examples that contain nominal argument patterns at the phrasal and sentence levels. The main objective of MultiGenera is the development of a simulator for the automatic generation of phrases in Spanish, German and French, which is based on the argument patterns of ten valency nouns. The second one, MultiComb, aims to automatically generate the phrasal and sentence contexts of the previously selected nouns in MultiGenera. In the present study we focus on the description of resource interoperability and a set of tools developed to support the methodology of both projects.Fundación BBVAAgencia Estatal de Investigación | Ref. FFI2017-82454-
Priority coalitional games and claims problems
No full textIn this paper, we analyze priority coalitional games as an extension of balanced games with transferable utility. Here, conditions imposed by a stable allocation used in the past need to be respected when deciding on a new allocation of the revenues obtained by the grand coalition. Using claims problems as a tool, we define weak and strong priority games with respect to a given allocation and a priority coalition, and study their properties and core. In the weak priority game, the value of a coalition reflects that coalitional members with priority should not be harmed, i.e., the coalitional value should never be below their total benefits according to the initial allocation. In the strong priority game, in addition to the previous condition, players outside the coalition that are not in the priority group should not harbour aspirations exceeding those benefits given by the initial allocation. Priority games are also extended to analyze cooperation restricted by a hierarchical structure. These games restrict the core so that desirable monotonicity properties are satisfied when there is a hierarchy. This allows for reconciling core selection and monotonicity over a hierarchy.Xunta de Galicia | Ref. ED481A 2021/325Agencia Estatal de Investigación | Ref. PID2021-124030NB-C3
The dark side of boys’ compliments to girls: exploring their relationship with sexism and cyberviolence towards intimate partners
No full textThe objective of this study was to evaluate the frequency with which boys “compliment” girls, know their perceptions about whether girls like compliments, and discen whether they believe that society expects them to make such comments. The relationship of such compliments with the level of ambivalent sexism and cyberviolence towards the partner was also evaluated. A total of 498 adolescent boys participated in this study, with a mean age of 16.01 years (SD = 1.02), recruited with the Computer-Assisted Web Interviewing (CAWI) system. The main results obtained show that younger boys more frequently emit objectifying messages about women’s bodies than older boys. They believe these comments positively impact girls, thinking they are appreciated. These boys, especially younger boys, show higher levels of hostile and benevolent sexism and perform more cyberviolence towards their partners. Boys’ level of partner cybercontrol predicts the emission of comments about women’s bodies, especially in boys with a high level of hostile sexism. Therefore, to prevent sexual harassment, gender-based cyberviolence, and sexism, it is crucial for the educational system to promote comprehensive sex education.Agencia Estatal de Investigación | Ref. PID2019-109613RB-I00Xunta de Galicia | Ref. ED431B2023/2
Buenas prácticas em Educación infantil: una revisión sistemática
No full textLa investigación sobre “Buenas Prácticas” se ha instaurado como un aspecto fundamental en el campo de la educación en los últimos años. Sin embargo, se trata de un concepto borroso, sin un consenso científico claro. El objetivo de este estudio fue analizar qué se entiende por Buenas Prácticas en Educación Infantil (0 a 6 años) en la investigación científica. Para ello, se realizó una Revisión Sistemática de Literatura siguiendo los principios PRISMA 2020. El objetivo principal fue reconocer los elementos que identifican las producciones científicas que describen Buenas Prácticas desde el 2014 al 2024, en inglés, español, portugués y francés, en las 3 bases de datos de mayor relevancia en nuestro campo (Scopus, Web of Science y SciELO). Los principales resultados muestran que bajo el término Buenas Prácticas se encuentran variedad de publicaciones con escasa fundamentación teórica y que se refieren a aspectos muy diversos. Se concluye que es fundamental continuar profundizando en este campo para asentar el concepto de Buenas Prácticas, que pueda ser compartido por los expertos y sus resultados transferidos en el campo de la Educación Infantil. Palabras clave: Revisión de literatura, buenas prácticas, educación infantil.Research on ‘Best Practices’ has become a fundamental aspect of the field of education in recent years. However, it is a vague concept without a clear scientific consensus. The objective of this study was to analyse what is meant by Best Practices in Early Childhood Education (0 to 6 years) in scientific research. A Systematic Literature Review was conducted following the PRISMA 2020 principles. The main objective was to recognise the elements that identify scientific publications describing Best Practices from 2014 to 2024, in English, Spanish, Portuguese and French, in the three most relevant databases in our field (Scopus, Web of Science and SciELO). The main results show that under the term “Best Practices” there are a variety of publications with little theoretical basis that refer to very diverse aspects. It is concluded that it is essential to continue to delve deeper into this field in order to establish the concept of Best Practices, which can be shared by experts and whose results can be transferred to the field of Early Childhood Education.Agencia Estatal de Investigación | Ref. PID2023-148530NA-I0
Reasons why older adults engage in physical exercise. Comparative study Eastern Europe versus Southern Europe
No full textResearch on variables that encourage older adults to exercise is limited. This study was carried out to identify the participation motives of older Europeans involved in regular exercise. Methods : The 418 (170 men, 248 women) who participated in the survey are participants of the Erasmus Plus European Project In Common Sports . The participants were divided into two groups. Italy, Portugal, and Spain formed the Southern Europe group, and Bulgaria and Hungary the Eastern European group. All participants completed the Participation Motivation Questionnaire: Older Adults. Results : The most highly reported motives for participation were to have fun, stay in shape, keep healthy, and an enjoyment of exercise. Principal-components analysis of the questionnaire revealed six factors: social, fitness, recognition, challenge/benefits, medical, and involvement. Conclusions : The reasons why the residents of Southern European practice exercise are more related to medical reasons, while for Eastern Europe these reasons are more related to recognition