258 research outputs found
Concepciones docentes acerca de la naturaleza de la tecnología y de las relaciones Ciencia, Tecnología, Sociedad y Ambiente en la educación tecnológica.
This paper aims, firstly, to question widespread conceptions of technology, presented as a simple application of scientific knowledge, which are contributing to a distorted and impoverished view of the nature of science and technology and, therefore, to students' lack of interest and even rejection of the study of techno-scientific subjects. Secondly, we present an analysis of how these conceptions affect teachers in charge of technological literacy. Finally, we contemplate how to overcome these conception
Imagen de la tecnología transmitida por los textos de educación tecnológica
Cuestionamos en este artículo la transmisión por los textos de tecnología de una visión simplista y socialmente neutra de la tecnología como "ciencia aplicada", ignorando, o tratando muy superficialmente, las complejas relaciones ciencia-tecnología-sociedad-ambiente (CTSA)
First report of Aphria latifrons (Diptera, Tachinidae, Leskiini) in the Canary Islands
The Canary Islands are an archipelago of volcanic origin, located off north-west Africa comprising eight islands. Fuerteventura and Lanzarote are the oldest (20 and 15 millon years old, respectively) and the easternmost islands. The order Diptera is one of the most relevant taxa in the Canary Islands as they constitute the second highest species richness. Within this order, the family Tachinidae is especially interesting as all species are endoparasitoids of arthropods and most species play a key role as pollinators. In the Canary Islands, the family comprises 52 species, with Fuerteventura and Lanzarote harbouring up to 20 species each.Aphria latifrons, a Palaearctic tachinid fly, is reported for the first time from the Canary Islands, where it was found on Fuerteventura and Lanzarote. Morphological examination was carried out and the first known barcode of the species is presented. Its potential distribution and source of origin are discussed
Overcoming the oblivion of technology in physics education
Technology is generally viewed as ‘applied science’, that is to say, as something that comes ‘after’
science. This conception justifies the lack of attention paid to technology in science education, especially where
physics education is concerned. In this chapter we question this simplistic view of the science-technology
relationship, historically rooted in the unequal appreciation of intellectual and manual work, and we try to show
how the absence of the technological dimension in science education contributes to a naïve and distorted view of
science which deeply affects the necessary scientific and technological literacy of all citizens, as well as the
preparation of the future scientists and technicians that our societies demand
Modelling of atmospheric hazards and severe weather phenomena toWestern Mediterranean basin coastal floods since 1960
The main goal of this study is to present a methodological approach to improve synoptic classifications associatedto basin coastal floods. A further step is done towards an objective reclassification of new events to improve andfacilitate the task of flooding weather forecast.In a recent study, we identified more than 3,600 cases of flood in the municipalities of the Spanish Mediterraneancoast from 1960 to 2013, and analyzed synoptic patterns associated to them. A Principal Sequence Pattern Analysiswas applied to sea level pressure, temperature at 850 hPa, geopotential at 700 hPa and 500 hPa (data provided bythe 20th Century V2 Reanalysis Project). The methodology used is based on three steps: (1) Principal SequenceComponent Analysis in S-mode, the scree-test to determine the number of components involved and OrthogonalVarimax rotation to minimise the number of variables with high factorial loadings; (2) Cluster Analysis to de-termine the main synoptic patterns associated with flooding activity in the study area using the non-hierarchicalK-means and the hierarchical Ward clusters; and (3) Discriminant Analysis for validating the model. The resultsshowed twelve Principal Sequence Patterns related to atmospheric convection associated with a trough in the mid-dle levels of the troposphere, and to thermal forcing. Regional differences are modulated by a triggering effect dueto local convergences.Once the synoptic patterns were identified, the new flood time-series recollected for 2014 and 2015 have beenreclassified from the component score coefficients matrix and Discriminant Fisher Functions of the reference period(1960-2013). The component scores were calculated from the following equation:Aij=SBikCkjWhere Aijis the score value at time i for the PCA component (j); Bikis the variable at time (i) at the grid point(k); and Ckjis the component score coefficient at the grid point (k) and PCA component (j).2) To classify new events, we used the Fisher discriminant functions:SP= maxt{Zt+SAjtXjt}Where SP is the predicted synoptic pattern; Ztis the constant coefficient of the Fisher discriminant function forthe synoptic pattern (t); Ajtis the score value of the PCA component (j) for the synoptic pattern (t); and Xjtis theFisher function coefficient for the PCA component (j) and the synoptic pattern (t).In comparison to other techniques, the method applied in this study obtains the discriminant functions that can be applied to reclassify a classification, as we did in this study, or to classify flood events in the future. Consequently,in a Meteorological Service, this tool could be an operational system for classifying any flood synoptic pattern fora period of 6-hours and delimiting the more likely flooding areas for the studied region.Peer ReviewedPostprint (published version
Concepciones acerca de la naturaleza de la tecnología y de las relaciones Ciencia, Tecnología, Sociedad y Ambiente en la educación tecnológica
Este trabajo pretende, en primer lugar, cuestionar extendidas concepciones de la tecnología que la presentan como mera aplicación de los conocimientos científicos y que están contribuyendo a una imagen distorsionada y empobrecida de la naturaleza de la ciencia y la tecnología y, consecuentemente, al desinterés e incluso rechazo hacia su estudio. En segundo lugar se presentan los resultados de una investigación cuyo objetivo es analizar en qué medida dichas concepciones afectan incluso al profesorado encargado de la alfabetización tecnológica. Finalmente se aborda la transformación de dichas concepciones.This paper aims, firstly, to question widespread conceptions of technology, presented as a simple application of scientific knowledge, which are contributing to a distorted and impoverished view of the nature of science and technology and, therefore, to students' lack of interest and even rejection of the study of techno-scientific subjects. Secondly, we present an analysis of how these conceptions affect even teachers in charge of technological literacy. Finally, we contemplate how to overcome these conceptions
Synoptic patterns associated to Western Mediterranean basin coastal floods since 1960
The analysis of long time-series related to floods supports the identification of climatic/synoptic processes naturally governing the occurrence of flooding and thus improves the projection of these hydrologic extremes.
The aim of this study is to analyze synoptic patterns associated to Spanish Mediterranean coast floods since 1960.
To collect the flood database we have explored the archives of all newspapers with a presence in the area. The searches have been made by typing the name of each of the 180 municipalities of the Spanish coast followed by 5 key terms. Additionally, we have consulted the specific bibliography to rule out any data gaps. This work has allowed to identify more than 3600 cases of flood in the municipalities of the Spanish Mediterranean coast.
The methodology to analyze the synoptic patterns is based on the Principal Sequence Pattern Analysis applied to sea level pressure, temperature at 850 hPa, and geopotential at 700 and 500 hPa. The data is obtained from the 20th Century V2 Reanalysis Project at 2.5 ° horizontal resolution. We used a 7-days sequence defined by the flood-date (key-date), given by the flood record, plus the 6-days before this date, to evaluate the evolution of the synoptic configuration. The methodology includes three steps: (1) Principal Sequence Component Analysis in S-mode, the scree-test to determine the number of components involved and Orthogonal Varimax rotation to minimize the number of variables with high factorial loadings; (2) Cluster Analysis to determine the main
synoptic patterns associated with flooding activity in the study area using the non-hierarchical K-means and the hierarchical Ward clusters; and (3) Discriminant Analysis for validating the model.
The results show twelve Principal Sequence Patterns linked to coast floods in the Mediterranean basin of the Iberian Peninsula. The patterns are characterized by low-pressure systems related to cold fronts with a strong and sudden deepening of the cyclone in North Africa which moved northwards over the Mediterranean advecting
warm and wet air at the low levels of the troposphere. Predominant flows are, first, from the south to southeast and, second, from the east, enhancing severe convective events. Furthermore, the stagnation of the synoptic configuration due to the presence of the high-pressure system over Europe favors long-lasting rainfall.Peer ReviewedPostprint (published version
Nonionizing electromagnetic field: A promising alternative for growing control yeast
In the food industry, some fungi are considered to be common spoilage microorganisms which reduce the shelf life of products. To avoid this outcome, different technologies are being developed to control their growth. Electromagnetic fields (EMF) have been used to combat bacterial growth, but there are few studies on yeasts and their possible action mechanisms. For this reason, we studied the effect of EMF between 1 to 5.9 GHz bands on the growth of Saccharomyces cerevisiae yeast and observed that all the frequencies of the band used cause the reduction of the viability of this yeast. In addition, we observed that the distance between the antenna and the sample is an important factor to consider to control the growing yeast. By using transmission electron microscopy, we found that the EMF caused a loss of continuity of the yeast cell membrane. Therefore, EMF may be used as a control method for yeast growth.Fil: Riffo, Byron. Universidad de Santiago de Chile; ChileFil: Henríquez, Consuelo. Universidad de Santiago de Chile; ChileFil: Chávez, Renato. Universidad de Santiago de Chile; ChileFil: Peña, Rubén. Universidad de Santiago de Chile; ChileFil: Sangorrin, Marcela Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; ArgentinaFil: Gil Duran, Carlos. Universidad de Santiago de Chile; ChileFil: Rodríguez, Arturo. Universidad de Santiago de Chile; ChileFil: Ganga, María Angélica. Universidad de Santiago de Chile; Chil
Assessment of the Association of Health with the Liberalisation of Trade in Services under the World Trade Organisation
Background: The liberalisation of trade in services which began in 1995 under the General Agreement on Trade in Services (GATS) of the World Trade Organisation (WTO) has generated arguments for and against its potential health effects. Our goal was to explore the relationship between the liberalisation of services under the GATS and three health indicators – life expectancy (LE), under-5 mortality (U5M) and maternal mortality (MM) - since the WTO was established. Methods and Findings: This was a cross-sectional ecological study that explored the association in 2010 and 1995 between liberalisation and health (LE, U5M and MM), and between liberalisation and progress in health in the period 1995–2010, considering variables related to economic and social policies such as per capita income (GDP pc), public expenditure on health (PEH), and income inequality (Gini index). The units of observation and analysis were WTO member countries with data available for 2010 (n = 116), 1995 (n = 114) and 1995–2010 (n = 114). We conducted bivariate and multivariate linear regression analyses adjusted for GDP pc, Gini and PEH. Increased global liberalisation in services under the WTO was associated with better health in 2010 (U5M: 20.358 p,0.001; MM: 20.338 p = 0.001; LE: 0.247 p = 0.008) and in 1995, after adjusting for economic and social policy variables. For the period 1995–2010, progress in health was associated with income equality, PEH and per capita income. No association was found with global liberalisation in services. Conclusions: The favourable association in 2010 between health and liberalisation in services under the WTO seems to reflect a pre-WTO association observed in the 1995 data. However, this liberalisation did not appear as a factor associated with progress in health during 1995–2010. Income equality, health expenditure and per capita income were more powerful determinants of the health of populations.This study was funded by the Carlos III Health Institute and the Programme for Promotion of Biomedical and Health Sciences (http://www.isciii.es/) of the Spanish Ministry of Health and Consumer Affairs (Ref. PI060295)
Microwave-induced covalent functionalization of few-layer graphene with arynes under solvent-free conditions
A non-conventional modification of exfoliated few-layer graphene (FLG) with different arynes under microwave (MW) irradiation and solvent-free conditions is reported. The described approach allows reaching fast, efficient and mild covalent functionalization of FLG.M. P. is the recipient of the AXA Chair (2016-2023). This work was supported by the EU H2020-Adhoc-2014-20 Graphene Core1 (no. 696656)S
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