Do Spanish Stock Market Prices Follow a Random Walk?

In this article we test the random walk hypothesis in the Spanish daily stock market prices by means of using fractionally integrated techniques. We use a version of the tests of Robinson (1994) that permit us to test I(d) statistical models. The results show that though fractional degrees of integration are plausible in some cases, the confidence intervals are generally narrow, including the unit root in all cases. Therefore, there is very little evidence of fractional integration, despite the length of the series, implying that the standard practice of taking first differences when modelling stock prices is adequate. In addition, the tests cannot reject that the underlying I(0) disturbances are white noise, supporting thus the (weakly) efficient market hypothesis in the Spanish stock market.Stock market; Unit roots; Long memory; Market efficiency

Testing of Nonstationary Cycles in Financial Time Series Data

In this article we propose a new method for testing nonstationary cycles in financial time series data. In particular, we use a procedure due to Robinson (1994) that permits us to test unit root cycles in raw time series. These tests have several distinguishing features compared with other procedures. In particular, they have a standard null limit distribution and they are the most efficient ones when directed against the appropriate alternatives. In addition, the procedure of Robinson (1994) allows us to test unit root cycles at each of the frequencies, and thus permits us to approximate the number of periods per cycle. The results, based on the daily structure of the Spanish stock market prices (IBEX 35) show that some intra-year cycles occur, and they take place at approximately 6, 9 or between 24 and 50 periods.Stock market; Unit root cycles; Nonstationarity

Interactome Data and Databases: Different Types of Protein Interaction

In recent years, the biomolecular sciences have been driven forward by overwhelming advances in new biotechnological high-throughput experimental methods and bioinformatic genome-wide computational methods. Such breakthroughs are producing huge amounts of new data that need to be carefully analysed to obtain correct and useful scientific knowledge. One of the fields where this advance has become more intense is the study of the network of ‘protein–protein interactions’, i.e. the ‘interactome’. In this short review we comment on the main data and databases produced in this field in last 5 years. We also present a rationalized scheme of biological definitions that will be useful for a better understanding and interpretation of ‘what a protein–protein interaction is’ and ‘which types of protein–protein interactions are found in a living cell’. Finally, we comment on some assignments of interactome data to defined types of protein interaction and we present a new bioinformatic tool called APIN (Agile Protein Interaction Network browser), which is in development and will be applied to browsing protein interaction databases

Rheas, mockinbirds and the "creation" of evolution

Las ideas de cambio evolutivo y de selección natural fueron dos contribuciones extraordinarias de la ciencia del siglo XIX; Charles Darwin formalizó la primera sobre la base de algunos antecedentes notables e inventó la segunda, pero fue reticente a publicarlas en forma temprana. Ciertas afirmaciones del propio Darwin generaron la impresión de que, tras su retorno del viaje del Beagle, permaneció registrando y ordenando datos y realizando nuevas observaciones en búsqueda de una explicación (mecanismo causal) del cambio evolutivo. Ese relato podría no ajustarse a los hechos porque Darwin parece haber concebido sus ideas tempranamente, tal vez antes de 1840, aunque permaneció elaborándolas durante años. Su pretensión era publicarlas una vez que la evidencia en su favor fuera indudable. Temeroso de la opinión crítica de colegas y legos, Darwin examinó su teoría detalladamente, poniendo en evidencia sus supuestos más restrictivos y deduciendo “observaciones esperadas” en diversos escenarios, para los que con cierta frecuencia encontró contraejemplos. La demora de Darwin en publicar no se debió a que estuviera buscando la explicación; contaba con ella pero permaneció evaluando su confiabilidad. El proceso de concepción de la teoría evolutiva muestra que la creatividad es fundamental en el avance del conocimiento y, por esa razón, constituye un modelo valioso para la enseñanza de la ciencia.The ideas of evolutionary change and natural selection were two extraordinary contributions of 19th-century science to culture and society. Charles Darwin formalized the first idea from some outstanding antecedents and entirely invented the second one, although he delayed the publication of both. Some of Darwin’s own comments gave rise to the impression that he deferred publication because he remained summarizing information and making new observations while searching for an explanation of evolutionary change (i.e., the causal mechanism). This story might not fit the facts, however, since Darwin appears to have conceived his theory very soon in his life, perhaps before 1840. Apparently, Darwin aspired to publish the theory only when it appeared unquestionable but when he wrote down his ideas in detail exposing its critical assumptions and deducing several “expected observations” he noted numerous drawbacks in both. Fearful of the reactions of their colleagues, he delayed publishing the theory. Darwin did not postpone publication because he was looking for the explanation of evolutionary change between 1840 and 1858; he already had the explanation and remained obsessively testing it. The process through which evolutionary theory was conceived highlights the key role of creativity in the development of human knowledge and, therefore, constitutes a valuable model to consider when teaching about “scientific discoveries”.Fil: Marone, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Pontificia Universidad Católica de Chile; ChileFil: Lopez de Casenave, Javier Nestor. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Grupo de Investigación en Ecología de Comunidades del Desierto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Glyphosate and AMPA concentrations in wind-blown material under field conditions

Agricultural intensification in fragile arid and semiarid environments has led to an increase in soil degradation, mainly through wind erosion. Argentina is an agricultural and cattle-farming country, which has increased its productivity in the last few decades, widening the boundaries of farm land and the use of herbicides to control weeds. Glyphosate, which accounts for 65% of the Argentinian pesticides market, is strongly retained in soil. The World Health Organization concluded that there was evidence to classify glyphosate as ‘probably carcinogenic to humans.’ In this context, the objective of this study was to determine the presence and concentration of glyphosate and aminomethylphosphonic acid (AMPA) in wind-blown material in 3 areas in Argentine semiarid regions (Chaco, La Pampa, and San Luis). In 1-ha2 plots, left uncovered and levelled, the wind-blown material was collected at heights of 13.5, 50, and 150 cm during 18 erosion events. The wind-blown material carried by the wind at a height of 150 cm had concentrations of 247 and 218 μg kg−1 of glyphosate and AMPA, respectively. This material was enriched 60 times in glyphosate and 3 times in AMPA as compared with the original soil. This shows that the eroded material can, potentially, have a negative impact on the ecosystem and also on human health, depending on the proportion of this material released into the atmosphere in suspension as particulate matter. This study is, to our knowledge, the first to report concentrations of glyphosate and AMPA in wind-blown material under field conditions.Fil: Aparicio, Virginia Carolina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aimar, Silvia Beatriz. Universidad Nacional de La Pampa. Facultad de Agronomía; ArgentinaFil: de Gerónimo, Eduardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mendez, Mariano Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Costa, Jose Luis. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentin

Direct introduction of nitrogen and oxygen functionality with spatial control using copper catalysis.

Synthetic chemists have spent considerable effort optimizing the synthesis of nitrogen and oxygen containing compounds through a number of methods; however, direct introduction of N- and O-functionality remains challenging. Presented herein is a general method to allow for the simultaneous installation of N- and O-functionality to construct unexplored N-O heterocyclic and amino-alcohol scaffolds. This transformation uses earth abundant copper salts to facilitate the formation of a carbon-centered radical and subsequent carbon-nitrogen bond formation. The intermediate aminoxyl radical is terminated by an intramolecularly appended carbon-centered radical. We have exploited this methodology to also access amino-alcohols with a range of aliphatic and aromatic linkers

Toolpath dependent stability lobes for the milling of thin-walled parts

The milling of thin-walled parts can become a seriously complex problem because the parts have variable dynamics. Firstly, the dynamics evolution of the part has been calculated through Finite Element Method (FEM) analysis. Then, the 3D stability lobes have been calculated for the thin walls and the thin floor. Finally, several milling tests have been performed in order to validate the predictions made by the model

mTOSSIM: A simulator that estimates battery lifetime in wireless sensor networks

Knowledge of the battery lifetime of the wireless sensor network is important for many situations, such as in evaluation of the location of nodes or the estimation of the connectivity, along time, between devices. However, experimental evaluation is a very time-consuming task. It depends on many factors, such as the use of the radio transceiver or the distance between nodes. Simulations reduce considerably this time. They allow the evaluation of the network behavior before its deployment. This article presents a simulation tool which helps developers to obtain information about battery state. This simulator extends the well-known TOSSIM simulator. Therefore it is possible to evaluate TinyOS applications using an accurate model of the battery consumption and its relation to the radio power transmission. Although an specific indoor scenario is used in testing of simulation, the simulator is not limited to this environment. It is possible to work in outdoor scenarios too. Experimental results validate the proposed model.Junta de Andalucía P07-TIC-02476Junta de Andalucía TIC-570

Behavioral traits predicting cocaine-conditioned place reference in mice: role of anxiety adn the basolateral amygdala

Aims. The individual susceptibility to cocaine addiction, a factor of interest in the understanding and prevention of this disorder, may be predicted by certain behavioral traits. However, these are not usually taken into account in research, making it difficult to identify whether they are a cause or a consequence of drug use. Methods. Male C57BL/6J mice underwent a battery of behavioral tests (elevated plus maze, hole-board, novelty preference in the Y maze, episodic-like object recognition memory and forced swimming test), followed by a cocaine-conditioned place preference (CPP) training to assess the reinforcing effect of the drug. In a second study, we aimed to determine the existence of neurobiological differences between the mice expressing high or low CPP by studying the number of neurons in certain addiction-related structures: the medial prefrontal cortex, the basolateral amygdala and the ventral tegmental area. Results. Anxiety-like behaviors in the elevated plus maze successfully predicted the cocaine-CPP behavior, so that the most anxious mice were also more likely to search for cocaine in a CPP paradigm. In addition, these mice exhibited an increased number of neurons in the basolateral amygdala, a key structure in emotional response including anxiety expression, without differences in the others regions analyzed. Conclusions. Our results suggest a relevant role of anxiety as a psychological risk factor for cocaine vulnerability, with the basolateral amygdala as potential common neural center for both anxiety and addiction.Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech. PSI2013-44901-P, FPU13/04819, CD12/00455, Red de Trastornos Adictivo

Técnicas tradicionales de construcción en Lanzarote

Se desarrollan los aspectos tipológicos y constructivos de la arquitectura tradicional de Lanzarote, estudiando los materiales de construcción (piedra, madera, barro y cal), los sistemas constructivos (muros y sus aparejos, forjados y cubiertas, bóvedas, aljibes y hornos y balcones y elementos de madera)