1,464 research outputs found
The board of directors and dividend policy: the effect of gender diversity
In this article, we aim to study the impact on dividends policy of gender diversity on the board of directors (hereinafter BD). We hypothesize that the proportion of women directors, the proportion of independent, institutional, and executive female directors, and the percentage of shares held by female directors on BD, have an impact on the dividends policy of Spanish companies. Our findings, analyzing the whole sample, show that the proportion of female directors and shares held by female directors are positively associated with dividend payout, while the percentage of institutional female directors has a negative impact. The percentage of independent and executive female directors has no effect on dividend payout. When companies with losses are removed from the sample, the findings report that the percentage of female directors on BD and the percentage of independent female directors impact positively on dividend policy, while the percentage of institutional and executive female directors has a negative effect. The proportion of shares held by female directors on BD does not have an effect on dividend payout when only companies with profits are examined. Thus, the results confirm that gender diversity has an influence on dividend payout, so the existing legislation should encourage more participation by women in governing bodies. Our evidence supports the Act for Effective Equality between Women and Men, which establishes that listing companies have to achieve a quota of 40% of women in decision-making bodies by 2015
Final state interaction effects in neutrino-nucleus quasielastic scattering
We consider the charged-current quasielastic scattering of muon neutrinos on
an Oxygen 16 target, described within a relativistic shell model and, for
comparison, the relativistic Fermi gas. Final state interactions are described
in the distorted wave impulse approximation, using both a relativistic mean
field potential and a relativistic optical potential, with and without
imaginary part. We present results for inclusive cross sections at fixed
neutrino energies in the range 200 MeV - 1 GeV, showing that final
state interaction effects can remain sizable even at large energies.Comment: 4 pages, 4 figures; poster session of the Third International
Workshop on Neutrino-Nucleus Interactions in the Few GeV Region (NuInt04),
Gran Sasso (Italy), March 17-21, 2004; to appear in the proceeding
Variation in Sensitivity of Different Grapevine Genotypes to Erysiphe necator Growing under Unfavourable Climatic Conditions
This paper reports the susceptibility to powdery mildew of 41 grapevine genotypes growing in the north and northwest of Spain over a three-year period. Although the humid climate of these vine-growing areas is not particularly favourable to the development of this disease, serious damages appears in some years when dry weather alternates with times of some rain. All the examined genotypes belonged to the collection of the Misión Biológica de Galicia (CSIC) (Pontevedra, Galicia, Spain). The incidence and severity of powdery mildew were determined on leaves three weeks after the onset of flowering and on clusters at harvest. The values for both variables were smaller than those recorded for other fungal diseases, although great differences in susceptibility between the different genotypes were observed. The most susceptible was Castañal (recently included in the Spanish Registry of Commercial Varieties), a genotype native to the O Rosal subzone of the Rias Baixas denomination of origin area. The present results could help viticulturalists grow different grapevine genotypes more successfully in regions with climatic conditions similar to those where the study was undertaken
Corporate social and environmental disclosure as a sustainable development tool provided by board sub-committees: Do women directors play a relevant moderating role?
he aim of this research is to examine the impact of three audit committee characteristics on corporate social and environmental responsibility (CSR) disclosure: the existence of an audit committee, audit committee independence, and audit committee financial expertise. Moreover, this research analyzes the moderating effect of board gender diversity between these audit committees' attributes and CSR reporting. The results of analyzing 13,178 firm-year observations of non-financial companies show that the presence of an audit committee and audit committee financial expertise are positively associated with CSR disclosure. However, a higher proportion of non-executive directors in audit committees has a negative effect on the disclosure of CSR information. These findings suggest that some audit committees' features play an important role in ensuring the reporting of environmental, social, and economic information. Our evidence also indicates that the presence of female directors on boards increases the positive impact of financial expert membership of audit committees on CSR disclosure, while women directors moderate any negative effect of the percentage of independent directors on audit committees on CSR reporting by increasing the latter. In addition, female directors moderate the positive impact of the existence of an audit committee on the disclosure of CSR information by reducing the latter
A Methodology Based on Machine Learning and Soft Computing to Design More Sustainable Agriculture Systems
©2023. This manuscript version is made available under the CC-BY 4.0 license http://creativecommons.org/licenses/by /4.0/
This document is the Published, version of a Published Work that appeared in final form in Sensors. To access the final edited and published work see https://doi.org/10.3390/s23063038Advances in new technologies are allowing any field of real life to benefit from using
these ones. Among of them, we can highlight the IoT ecosystem making available large amounts
of information, cloud computing allowing large computational capacities, and Machine Learning
techniques together with the Soft Computing framework to incorporate intelligence. They constitute
a powerful set of tools that allow us to define Decision Support Systems that improve decisions in a
wide range of real-life problems. In this paper, we focus on the agricultural sector and the issue of
sustainability. We propose a methodology that, starting from times series data provided by the IoT
ecosystem, a preprocessing and modelling of the data based on machine learning techniques is carried
out within the framework of Soft Computing. The obtained model will be able to carry out inferences
in a given prediction horizon that allow the development of Decision Support Systems that can help
the farmer. By way of illustration, the proposed methodology is applied to the specific problem of
early frost prediction. With some specific scenarios validated by expert farmers in an agricultural
cooperative, the benefits of the methodology are illustrated. The evaluation and validation show the
effectiveness of the proposal
Las tecnologías de la información y las comunicaciones en la enseñanza superior española: factores explicativos del uso del campus virtual
En este trabajo se aborda el estudio empírico
de los factores que afectan al uso del campus virtual
por parte de los estudiantes de Administración y
Dirección de Empresas de la Universidad Católica San
Antonio.
Para el análisis nos hemos basado en el modelo de
aceptación de tecnología de Davis (1989). Los resultados
obtenidos confirman lo que dicho modelo propone:
la utilidad y la facilidad de uso percibida afectan positivamente
a la actitud hacia esta herramienta tecnológica.
Además, la actitud y la obligatoriedad percibida
influyen de manera positiva en el uso de la misma.
Se ha comprobado también la influencia que tienen en
el uso del campus virtual algunas variables de carácter
socioeconómico. Nuestro estudio nos permite concluir que el sexo, la edad y la situación laboral dan lugar a
cambios en los factores determinantes de la conducta
analizada.
Las conclusiones del trabajo permiten no solo conocer
de una forma más completa qué factores afectan a la
percepción, actitudes y comportamientos de los estudiantes
universitarios hacia el campus virtual, sino que
permiten también plantear propuestas para conseguir
una implantación más efectiva de esta herramienta
tecnológica en la universidad
Sliding wear resistance of biomorphic SiC ceramics
Biomorphic SiC ceramics were fabricated from four different wood precursors and their Knoop hardness and sliding wear resistance when sliding against a Si3N4 ball in air were studied. Tribological experiments were performed using a pin on disk apparatus, under normal loads of 2 and 5 N, at a sliding speed of 100 mm/s. The effects of specimen porosity and microstructure on measured wear were evaluated. A commercial sintered silicon carbide ceramic was also tested for comparison. Small differences in friction coefficient comparable to monolithic SiC ceramics were obtained. Several concurrent wear mechanisms are taking place: microfracture, plastic deformation in the Si phase and oxidation of the Si and/or SiC phase. The presence of an oxide tribolayer was assessed using fluorescence microscopy. Wear rates were found to scale with SiC content and depend on residual porosity in the composite.Peer reviewe
Nota corta. Análisis de heterogeneidad entre aislados de Mycoplasma pullorum por medio de técnicas de amplificación de DNA polimórfico
Mycoplasmas were isolated from chickens with respiratory problems during field investigations of a concentrated respiratory disease outbreak in western Cuba, 1997. A high percentage of mycoplasma cultures from tracheas and air-sac lesions yielded pure cultures of Mycoplasma pullorum. The aim of the present work was to investigate the heterogeneity among M. pullorum isolates from Cuba and strains from other countries using random amplified polymorphic DNA (RAPD) techniques. The results show that the RAPD method may be a useful identification tool for studying the epidemiology of poultry mycoplasmosis in Cuba.En 1997 se aislaron micoplasmas en el curso de investigaciones de campo en pollos con un brote de enfermedad respiratoria localizada en la zona oeste de Cuba. Un alto porcentaje de los cultivos de micoplasmas procedentes de lesiones de tráquea y alveolos revelaron la presencia de Mycoplasma pullorum. El objetivo de este trabajo fue investigar la heterogeneidad de los aislados cubanos entre sí y con cepas de otros países, mediante la técnica RAPD (DNA polimórfico amplificado al azar). Los resultados muestran que la técnica RAPD puede ser una herramienta de identificación útil en el estudio de la epidemiología de la micoplasmosis aviar en Cuba
Eficacia analgésica de diclofenaco versus metilprednisolona en el control del dolor postoperatorio tras la cirugía del tercer molar inferior
Objetivo: Comparar la eficacia analgésica de la metilprednisolona
(corticoide) versus diclofenaco (antiinflamatorio no
esteroideo-AINE-) tras la cirugía del tercer molar inferior.
Diseño del estudio: Estudio prospectivo sobre 73 pacientes
sometidos a la extracción quirúrgica de los terceros molares
inferiores. Fueron divididos de forma aleatoria en dos grupos:
De diclofenaco y de metilprednisolona. Se cumplimentó una
ficha donde se hizo constar los datos epidemiológicos y clínicos
preoperatorios y postoperatorios. La valoración del dolor se hizo
mediante escala visual analógica y semicuantitativa y número de
analgésicos de rescate consumidos. El control del dolor se hizo
en la primera hora, a las 8 horas, 24 horas, 48 y 72 horas.
Se usó el programa estadístico BMDP para hacer un amplio
tratamiento de los datos.
Resultados: En el dolor reflejado por los pacientes en la escala
visual analógica no hubo diferencias de conjunto entre los dos
grupos (aunque sí las hubo en ciertos momentos). Tampoco
hubo diferencias en el número de analgésicos de rescate consumidos.
Conclusiones. La reducción del dolor que se consigue con el
corticoide no es significativa por lo que no está justificado su
uso rutinario.Objetive: To compare the analgesic efficacy of methylprednisolone
(corticoid) versus diclofenac (nonsteroidal antiinflammatory-
NSAID-) after surgical removal of lower third molars.
Study Design: Prospective study on 73 patients for the surgical
removal of their lower third molars. These patients were
separated in two groups at random: a diclofenac group and a
methylprednisolone group. A record card was filled in with
preoperative and postoperative epidemiological and clinic data.
The pain level assessment was made on a semiquantitative and an
analogical visual scales and in relation to the amount of rescue
analgesics consumed. Pain levels were measured at 1, 8, 24, 48
and 72 hours.
In order to make a broad study of data, BMDP program was
used for statistics.
Results: In the pain described by patients in the analogical visual
scale there were no differences between groups as a whole.
There were no differences in the amount of rescue analgesics
consumed.
Conclusions. There is less pain in the corticoid group but not as
to justify its routine use
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