Ressenyes

Index de les obres ressenyades: Jeanne HERSCH, El gran asombro. La curiosidad como estímulo en la historia de la filosofí

Los fuegos del Etna

This work aims to analize the Latin texts that authors let us about the Aetna’s volcanic activity. Our research stars with some lucretian verses (VI 639-702), follows with other texts of the problematic poem Aetna and ends with two famous passages by Virgilio (Aen. III 570-587) and Ovid (Met. XV 340-355), all in order to know the literary treatment of a scientific matter

Trama y urdimbre de la escritura de Jeanne Hersch

Este artículo intenta presentar la originalidad del pensamiento de Jeanne Hersch y el sentido de su aportación a partir de un análisis de los elementos que componen la estructura de su obra. En este análisis se atiende, en primer lugar, a su relación con la tradición filosófica, y se destaca, a continuación, el papel de la escritura como forma de acción y la importancia del tema de la temporalidad

Thymine starvation causes abortive initiation of chromosome replication critical for cell death in Escherichia coli

Presentado en: XXXVI Congreso SEBBM (Sociedad Española de Bioquímica y Biología Molecular), Madrid, 4-6 septiembre, 2013Thymineless death (TLD), a phenomenon in which thymine auxotrophy becomes lethal when cells are starved for thymine, can be prevented by rifampicin addition. In this work, we have obtained evidence indicating that among the effects of RNA polymerase inhibition by rifampicin, the inhibition of chromosomal replication initiation is the process responsible for TLD suppression. We show that diminishing, abolishing or increasing the transcription level around oriC alleviates TLD by limiting the chromosomal initiation capacity (ChIC) generated under thymine starvation. TLD suppression was eliminated by DnaA inactivation or the deletion in the left half of the replication origin or deletion of the DnaA-boxes located in the right half of the oriC region. In accordance with these data, two-dimensional DNA electrophoresis gels showed an accumulation of simple-Y and bubble arc replication intermediates, as well as recombination structures at the oriC region during thymine starvation. None of these structures were observed under genetic or physiological conditions that suppress TLD. These results demonstrate that abortive initiations of chromosome replication occur under thymine starvation, supporting the idea that these events are a critical target for the lethal damage caused by thymine starvation and that results in TLD.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Influence of ecotourism on the conservation of wildlife and socioeconomic conditions of indigenous communities of the Yasuní National Park and its area of influence

This article aims to illuminate the influence of ecotourism on the conservation of wild fauna and socioeconomic conditions of indigenous communities living in and around the Yasuní National Park (YNP). To obtain relevant data, a survey was applied to 132 household (HH) heads of seven communities from the park...Este artículo pretende aclarar la influencia del ecoturismo en la conservación de la fauna silvestre y las condiciones socioeconómicas de las comunidades indígenas que viven en y alrededor del Parque Nacional Yasuní. Para obtener los datos pertinentes, se aplicó una encuesta a 132 jefes de hogar (JH) de siete comunidades del parque..

Modulation of bone metabolism and mineralization in gilthead seabream (Sparus aurata) fed various vegetable oil sources

Little information exists on the role of dietary lipids on the bone metabolism in fish. A trial was undertaken to evaluate the effect of dietary lipid sources as modulators of bone fatty acid composition, mineralization and skeletal metabolism in fast-growing seabream juveniles. Twelve homogenous groups of 25 seabream juveniles each (mean initial body weight of 39.3 1.4 g) were stocked in 90 L tanks and fed one of four semi-purified experimental diets formulated to be isonitrogenous (crude protein, 46% DM), isolipidic (15% DM) and isoenergetic, but with variable oils sources. The dietary lipid sources under testing were: a) cod liver oil (FO, a source of n-3 LC-PUFA); b) soybean oil (SBO, a source of n-6 fatty acids); c) linseed oil (LSO, a source of non-LC-PUFA n-3 fatty acids); and d) palm oil (PO, a source of saturated fatty acids). Overall growth performance criteria and whole-body composition of fish were not significantly affected by the various dietary experimental treatments (P>0.05). Bone fatty acid composition was altered by the dietary fatty acid profile, but suggests the existence of conservative mechanisms for some specific fatty acids, namely DHA. While the calcium content of bone was little affected by the dietary treatments, bone phosphorus level in seabream fed the cod liver oil diet was significantly higher (P0,05). A composição de ácidos gordos do osso foi alterada pelo perfil de ácidos gordos da dieta, mas sugere a existência de mecanismos de conservaçãos de alguns ácidos gordos específicos, nomeadamente do DHA. Embora o teor de cálcio do osso tenha sido pouco afetado pelos tratamentos alimentares, o nível de fósforo no osso de douradas alimentadas com a dieta de óleo de fígado de bacalhau foi significativamente superior (P<0,05) do que aqueles encontrados nos peixes alimentados com as dietas de óleo vegetal. A observação microscópica de tetraciclina marcado nas vértebras mostraram que a deposição mineral em vértebras de peixes alimentados com a dieta LSO foi significativamente menor (P<0,05) do que a encontrada nos peixes alimentados com dietas FO e SBO. Actividade da fosfatase ácida resistente ao tartarato (TRAP) em homogeneizado de osso foi positivamente correlacionada (r = 0,658) com ácido α-linolénico (ALA, 18:3 n-3), ao passo que um aumento da ingestão de EPA (r = -0,478) e DHA (r = -0,536) teve tendência a reduzir a atividade TRAP. Atividade de fosfatase alcalina (ALP) em homogeneizados de osso foi positivamente correlacionada com a ingestão de EPA (r = 0,763) e DHA (r = 0,793). Em comparação com os peixes alimentados com a FO e LSO dietas, aqueles alimentados com as dietas SBO e PO mostrou uma redução significativa (P <0,05) do total de fosfolipase A2 (PLA2) atividade em homogeneizados ósseos. No entanto, estas alterações não foram claramente associadas à actividade da PLA2 citosólica. Os resultados deste trabalho, confirmam que os lípidos alimentares desempenham um papel importante na modulação do metabolismo ósseo da dourada.Universidade do Algarve, Faculdade de Ciências e Tecnologi

Trainee teachers’ perceptions on cyberbullying in educational contexts

This paper analyzes the perceptions of teachers in training regarding cyberbullying in schools. The objectives of the study were: to ascertain their perceptions regarding their concern and their commitment to cyberbullying, their agreement with the measures to address it in educational contexts, as well as the assessment of their capabilities to act and the training they have received and they would like to receive; to determine if the perceptions differ according to gender, age and degree pursued and if there are relationships between the perceptions; and, to define pre-service teachers’ profiles based on perceptions. With a survey research design, 408 students from different undergraduate and graduate education-related degree programs at Spanish public universities participated. Findings highlight the coexistence of three different teacher in training profiles. All profiles exhibit a high level of concern and recognize cyberbullying as a problem. They strongly agree with all the proposed prevention and management measures. Two of the three profiles perceive themselves as highly confident and willing to respond. On the contrary, participants in the third profile do not feel confident enough to act and consider their training insufficient, coinciding with the second profile. The need to approach this issue in the initial training of future education professionals is a main conclusion

The relationship between knowledge management and innovation level in Mexican SMEs: Empirical evidence

The transformation of the current society from an industry-based economy to a knowledge management and innovation-based economy is changing the design and implementation of business strategies and the nature of the competition among the organizations which are mainly small and medium-size enterprises (SMEs). They struggle to survive in a market which is more demanding and competitive, so they seeknowledge management as one of the most effective strategies that may help to enable the innovation activities into the businesses. For these reasons, this research paper has as a main goal to analyze the relationship between knowledge management and innovation in Mexican SMEs. The empirical analysis used 125 manufacturing SMEs (each SME having from 20 to 250 employees) as a sample to be carried out. The obtained results indicate that knowledge management has a positive impact in products, process, and management systems innovation

Análisis de eficiencia por programas en el sector fundacional Español

This paper evaluates the performance of the foundation sector in Spain by applying the non-parametric technique of Data Envelopment Analysis (DEA), proposed by Charnes, Cooper, and Rhodes (1978) and Banker, Charnes, and Cooper (1984). The study is based on a sample of 172 Spanish foundations, framed inside the sub-sectors of care and educational–cultural foundations, both of them relevant in the national foundation sector. In order to measure the performance of these kind of non-profit organisations, we designed a model based on the economic and financial information obtained from the annual accounts for the period 2008–2010. We classified the sample according to the different types of foundations and applied the technique known as programme decomposition approach (Charnes, Cooper, & Rhodes, 1981) to determine which foundational model achieves a better management performance. Subsequently, the work was completed with the two-stage DEA analysis to evaluate the main factors that determine the management performance of these entities for the period of studyEl presente trabajo evalúa la eficiencia en la gestión de recursos y cumplimiento de fines del sector fundacional en España mediante la aplicación de la técnica no paramétrica del Análisis Envolvente de Datos (Data Envelopment Analysis, DEA) propuesto por Charnes, Cooper, and Rhodes (1978) y Banker, Charnes, and Cooper (1984). A partir de una muestra de 172 fundaciones estatales pertenecientes a los subsectores de fundaciones asistenciales y de educación y cultura, ambos de relevancia en el sector fundacional nacional, se diseñó un modelo de rendimiento basado en la información económico-financiera de sus cuentas anuales para el trienio 2008-2010, al que se le aplicó la técnica DEA por programas (Charnes, Cooper, & Rhodes, 1981) de acuerdo a la tipología de fundaciones, con el fin de conocer el modelo fundacional que mejor rendimiento alcanza, complementándose posteriormente el estudio con un análisis DEA en dos etapas para evaluar los principales factores determinantes del rendimiento de dichas entidades en el periodo estudiado.Administración y Dirección de Empresa