131 research outputs found
Forest Ecosystem Services: An Analysis of Worldwide Research
The relevance of forests to sustain human well-being and the serious threats they face have led to a notable increase of research works on forest ecosystem services during the last few years. This paper analyses the worldwide research dynamics on forest ecosystem services in the period from 1998 to 2017. A bibliometric analysis of 4284 articles was conducted. The results showed that the number of published research articles has especially increased during the last five years. In total, 68.63% of the articles were published in this period. This research line experiences a growing trend superior to the general publishing trend on forest research. In spite of this increase, its relative significance within the forest research is still limited. The most productive subject areas corresponded to Environmental Science, Agricultural and Biological Sciences and Social Sciences Economic topics are understudied. The scientific production is published in a wide range of journals. The three first publishing countries are United States, China and the United Kingdom. The most productive authors are attached to diverse research centres and their contributions are relatively recent. A high level of international cooperation has been observed between countries, institutions and authors. The findings of this study are useful for researchers since they give them an overview of the worldwide research trends on forest ecosystem services
The Sustainable Management of Metals: An Analysis of Global Research
The objective of this study was to analyze research trends in the field of sustainable management of metals on a global level between 1993 and 2017. To do so, a bibliometric analysis was carried out on a total of 6967 articles. The results revealed the growing interest in this research field, particularly over the last five year-period during which 63% of all articles were published. The three journals in which most articles had been published were the Journal of Cleaner Production, ACS Sustainable Chemistry and Engineering, and Chemsuschem. The countries that published the most articles were China, the United States, India, Germany, and the United Kingdom. A sizeable network of collaboration has been established between countries for the joint publication of studies. The main lines of research have been focused on metal decontamination in water and soil, waste management oriented towards reuse and recycling, and the innovation of processes for cleaner and more efficient production. The results revealed the need for comprehensive studies that integrate different disciplines within the same analytical framework, and to promote research that contributes to the different dimensions of sustainability (environmental, economic, and social)
Estudio de la violencia y conflictividad escolar en las aulas de educación primaria a través de un cuestionario de clima de clase: el caso de las provincias de Córdoba y Granada
Actualmente en la mayoría de las instituciones educativas existe un problema evidente, la violencia escolar. Numerosos estudios han mostrado datos sobre los índices de violencia en las aulas, los cuales nos sirven como base para justificar la necesidad de una educación para la convivencia en los centros escolares apoyada y reforzada por el trabajo conjunto de los docentes que desarrollan su labor educativa en dichos centros.
Este trabajo supone un acercamiento a una realidad educativa que esta muy presente en las aulas de los cursos superiores de los centros de Educación Primaria de las provincias de Córdoba y Granada del sur de España. El objetivo del estudio trata de plasmar y analizar las situaciones de conflictividad escolar y las relaciones entre el alumnado a nivel de aula, obteniendo así una visión general respecto al tema de la conflictividad y violencia escolar
Living on the Edge: Settlement Patterns by the Symbiotic Barnacle \u3cem\u3eXenobalanus globicipitis\u3c/em\u3e on Small Cetaceans
The highly specialized coronulid barnacle Xenobalanus globicipitis attaches exclusively on cetaceans worldwide, but little is known about the factors that drive the microhabitat patterns on its hosts. We investigate this issue based on data on occurrence, abundance, distribution, orientation, and size of X. globicipitis collected from 242 striped dolphins (Stenella coeruleoalba) that were stranded along the Mediterranean coast of Spain. Barnacles exclusively infested the fins, particularly along the trailing edge. Occurrence, abundance, and density of X. globicipitis were significantly higher, and barnacles were significantly larger, on the caudal fin than on the flippers and dorsal fin. Barnacles were found more frequently and in greater numbers on the dorsal rather than ventral side of the caudal fin and on the central third of dorsal and ventral fluke surfaces. Nearly all examined individuals attached with their cirral fan oriented opposite to the fluke edge. We suggest that X. globicipitis may chemically recognize dolphins as a substratum, but fins, particularly the flukes, are passively selected because of creation of vortices that increase contact of cyprids with skin and early survival of these larvae at the corresponding sites. Cyprids could actively select the trailing edge and orient with the cirri facing the main direction of flow. Attachment on the dorsal side of the flukes is likely associated with asymmetrical oscillation of the caudal fin, and the main presence on the central segment of the flukes could be related to suitable water flow conditions generated by fluke performance for both settlement and nutrient filtration
Fluorescence-Labeled Pyrenesulfonamide Response for Characterizing Polymeric Interfaces in Composite Materials
E-glass fibers were silanized using a 1% (v/v) aqueous solution of γ-aminopropyltriethoxysilane (APES). Pyrene—sulfonamide conjugates were formed by reaction of 1-pyrenesulfonyl chloride (PSC) in acetonitrile (AcN), with the amine groups immobilized on the glass fiber surface. These pyrene—sulfonamide conjugates were used as fluorescence probes, being a relatively simple analytical method to study the coating microstructure of polyorganosiloxane layer on glass fibers. The first aim of this work was to estimate possible interactions of the polyaminosiloxane coating with surrounding molecules of different solvents (solvent accessibility to the chromophore). For this study, the fluorescence response of pyrene—sulfonamide dye (PSA) was correlated with solvent polarity parameters. It was concluded that all the studied solvents were accessible to the chromophore, and they can gather in two groups, depending on their ability to swell the poliorganosiloxane layer. The second objective was to estimate the rigidity of the coating polymer from the temperature dependence of PSA emission. At about 180 K, a sudden change in the behavior of different photophysical parameters of PSA were observed. This phenomenon was interpreted as a density change in the polyaminosiloxane attached to the glass fibersThis research was supported by integrated actions Portugal–Spain, Reference HP1998-0014. J. Baselga, A. Aznar, and J. González-Benito wish to acknowledge the European Commission for support under the Brite-EuRam program (BE97-4472)
ABPgame: a videogame as a coordinated learning project for several subjects
Los tiempos demandan que formemos a los estudiantes universitarios para que tengan un papel activo en su aprendizaje, desde un enfoque interdisciplinar, favoreciendo el aprendizaje colaborativo y haciendo uso de la tecnología a su alcance. La metodología de Aprendizaje Basado en Proyectos (ABP) nos ofrece esta posibilidad. ABPgame es la adaptación de esta metodología a la impartición de cuatro asignaturas de la titulación de Ingeniería Informática en la que se ha utilizado como proyecto de aprendizaje el diseño y desarrollo en equipo de un videojuego. El artículo presenta los principios en los que se fundamenta la propuesta y describe la experiencia, haciendo énfasis en los pasos seguidos y las ventajas e inconvenientes encontrados, de forma que la misma pueda ser trasferida a otros ámbitos.Current times demand the university students to be trained to have an active role in their learning, from an interdisciplinary approach, encouraging collaborative learning and using technology at their disposal. The methodology of Project Based Learning (PBL) allows this possibility. ABPgame is the adaptation of this methodology to the teaching of four subjects of Computer Engineering degree in which the design and development of a computer game has been used as a learning project. This paper presents the underlying principles of our proposal and describes the experience, emphasizing the steps taken and the advantages and drawbacks found, so that the model may be transferred to other areas
Characterization of miniaturized metamaterial resonators coupled to planar transmission lines through parameter extraction
In this paper, a method for obtaining the electrical characteristics of metamaterial resonators coupled
to planar transmission lines is proposed. This parameter extraction technique is based on the
comparison between the measured or full wave electromagnetic simulated transmission and
reflection characteristics of a host line loaded with such resonators and those obtained from its
lumped element equivalent circuit model previously reported by some of the authors. The resonant
particles considered in this study are split ring resonators, spiral resonators, and other electrically
small resonant particles based on two metal levels. The interest in this technique lies in the lack of
analytical models providing the electrical parameters of several of the considered ultrasmall
resonator topologies due to their complexity. From the extracted parameters, it is concluded that
the circuit models predict very accurately the frequency responses of the considered structures for
the different resonators under study. There is an increasing interest in the synthesis of metamaterial
transmission lines with extremely small unit cell size. In order to achieve dimensions close to or
even below g /100, it is imperative to use complex resonator topologies that combine broadside
coupling and extremely elongated metallic strips etched in different metal levels connected through
vias. This justifies the proposed technique. Thus, this work is useful in aiding the synthesis of
microwave components based on resonant type metamaterial transmission lines.Ministerio de Educación y Ciencias de España-TEC2007-68013-C02 METAINNOVACentro de Innovación y Desarrollo de España-CIMITEC (UAB)-2005SGR0624Ministerio de Educación y Ciencias-(subvención FPU)-AP2005-452
Geological risk assessment of Amtoudi Agadir in southern Morocco: a key case for sustainable cultural heritage
Medieval fortified granaries known as “agadirs” are very common in southern Morocco, being catalogued as world cultural heritage by United Nations. These Berber buildings (made of stones and tree trunks) usually located on rocky promontories, constitute historical testimonials related to the origin of Morocco, and, as tourist attractions, have a positive impact on the local economy. The sustainability of these ancient monuments requires geological-risk evaluations of the massif stability under the agadir with the proposal of stabilization measures, and an architectonic analysis with appropriate maintenance of the structural elements. An interdisciplinary study including climate, seismicity, hydrology, geology, geomorphology, geotechnical surveys of the massif, and diagnosis of the degradation of structural elements have been performed on the Amtoudi Agadir, selected as a case study. The main findings from this study are that the prevalent rocks used for construction (coming from the underlying substratum) are good-quality arkosic sandstones; the SW cliffs under the agadir are unstable under water saturation; some masonry walls are too thin and lack interlocking stones and mortar; and failures in the beams (due to flexure, fracture, and exhaustion in the resistance due to insect attacks or plant roots) are common. The basic risk assessment of ancient buildings of cultural heritage and their geologic substratum are needed especially in undeveloped areas with limited capacity to implement durable conservation policies. Therefore, recommendations have been provided to ensure the stability and maintenance of this important archaeological site.This research was supported by Urbino University found (Resp. F. Guerrera); by CGL2011-30153-CO2-02 and CGL2012-32169 research project (Spanish Ministry of Education and Science); and by research groups and projects of the Generalitat Valenciana from Alicante University (CTMAIGA)
Actividad física, hidratación y salud
Since the beginning of mankind, man has sought ways to promote and preserve health as well as to prevent disease.
Hydration, physical activity and exercise are key factors for enhancing human health. However, either a little dose of them
or an excess can be harmful for health maintenance at any age.
Water is an essential nutrient for human body and a major key to survival has been to prevent dehydration. However, there is
still a general controversy regarding the necessary amount to drink water or other beverages to properly get an adequate level
of hydration. In addition, up to now the tools used to measure hydration are controversial. To this end, there are several
important groups of variables to take into account such as water balance, hydration biomarkers and total body water. A combination of methods will be the most preferred tool to find out any risk or situation of dehydration at any age range.
On the other hand, physical activity and exercise are being demonstrated to promote health, avoiding or reducing health
problems, vascular and inflammatory disea ses and helping weight management. Therefore, physical activity is also being
used as a pill within a therapy to promote health and reduce risk diseases, but as in the case of drugs, dose, intensity, frequency, duration and precautions have to be evaluated and taken into account in order to get the maximum effectiveness and success
of a treatment. On the other hand, sedentariness is the opposite concept to physical activity that has been recently recognized as an important factor of lifestyle involved in the obesogenic environment and consequently in the risk of the non-communicable diseases.
In view of the literature consulted and taking into account the expertise of the authors, in this review a Decalogue of global
recommendations is included to achieve an adequate hydration and physical activity status to avoid overweight/obesity consequences.Desde los comienzos del género humano, el hombre ha buscado el modo de promover y preservar la salud, así como prevenir la enfermedad. La hidratación, la actividad física y el ejercicio son factores clave para mejorar la salud. Sin embargo, estos factores en dosis excesivamente bajas o en exceso pueden ser perjudiciales para el mantenimiento de la salud a cualquier edad. El agua es un nutriente esencial para el organismo y un factor clave para la supervivencia y la prevención de la deshidratación. Sin embargo, hay todavía una controversia general en cuanto a la cantidad necesaria de ingesta de agua u otros líquidos con objeto de conseguir un nivel adecuado de hidratación. Además, hasta la fecha no hay consenso sobre las herramientas a utilizar para medir la hidratación. Con este fin, hay varios grupos importantes de variables a tener en cuenta, como el equilibrio de agua, biomarcadores de hidratación y el agua total corporal. Se prefiere en general una combinación de métodos para evaluar riesgo de situaciones de deshidratación en cualquier franja etaria. Por otro lado, se ha demostrado que la actividad física y el ejercicio promueven la salud, evitando o reduciendo la susceptibilidad a enfermedades de tipo vascular o inflamatorio, así como para ayudar en el manejo del peso. Por todo ello, la actividad física está siendo utilizada también a modo de “píldora” en terapias para promover la salud y reducir el riesgo de enfermedad. Como en el caso de los medicamentos, hay que evaluar la dosis, intensidad, frecuencia, duración y tener en cuenta las precauciones necesarias para conseguir la máxima eficacia y el mayor éxito del tratamiento. Por el contrario, el sedentarismo es el concepto opuesto a la actividad física y se ha reconocido recientemente como un factor importante de estilo de vida implicado en el ámbito obesogénico y en consecuencia en el riesgo de las enfermedades no transmisibles. Teniendo en cuenta la bibliografía consultada y la experiencia de los autores, en esta revisión se concluye con unas recomendaciones a modo de decálogo dirigido a la población general para conseguir un estatus de hidratación y actividad física adecuados con el fin de evitar las consecuencias del sobrepeso y la obesidad
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