Search results for " evidence"
showing 10 items of 632 documents
Imagen de marca y análisis lexicográfico: una aplicación a centros comerciales
2015
[EN] The concept of image in its different aspects is very important in today s society as well as in the business management field. Some authors reports that most of the studies that measure image do not take into account neither previous theoretical and conceptual models nor other possible empirical evidence alternatives. Given this need, a research regarding the concept of brand image applied to shopping malls was conducted based on the conceptual model of the consumer cognitive response in order to empirically explore and contrast it. For this reason, a survey was applied to 420 consumers in five shopping malls in Bogotá, achieving a database of 3.749 cases. The results show attribute-s…
Trace elements in natural metallic iron from Disko Island, Greenland
1986
The largest occurrence of natural metallic iron on Earth is on the island of Disko, Greenland. Metallic iron is found there in a variety of different types, from small metal particles in basalts to large meter-sized blocks. We have studied three different types of metallic iron: small metal spherules (< 300 μm) in basaltic magma; larger metal grains (300 μm-3 mm), often composed of aggregates of smaller particles, in similar host rocks; and massive iron lumps (up to several tons). Analytical data for 13 siderophile elements in samples from these three types are presented. All metals analysed have a distinctly crustal pattern of siderophile elements. High Co/Ni, Re/Ir or W/Ir ratios clearly …
First observational evidence for the CO&lt;sub&gt;2&lt;/sub&gt;-driven origin of Stromboli's major explosions
2011
Abstract. We report on the first detection of CO2 flux precursors of the till now unforecastable "major" explosions that intermittently occur at Stromboli volcano (Italy). An automated survey of the crater plume emissions in the period 2006–2010, during which 12 such explosions happened, demonstrated that these events are systematically preceded by a brief phase of increasing CO2/SO2 weight ratio (up to >40) and CO2 flux (>1300 t d−1) with respect to the time-averaged values of 3.7 and ~500 t d−1 typical for standard Stromboli's activity. These signals are best explained by the accumulation of CO2-rich gas at a discontinuity of the plumbing system (decreasing CO2 emission at the surfa…
Experimental observations of upstream overdeepening
2005
The issue of morphodynamic influence in meandering streams is investigated through a series of laboratory experiments on curved and straight flumes. Both qualitative and quantitative observations confirm the suitability of the recent theoretical developments (Zolezzi & Seminara 2001) that indicate the occurrence of two distinct regimes of morphodynamic influence, depending on the value of the width ratio of the channel β. The threshold value βR separating the upstream from the downstream influence regimes coincides with the resonant value discovered by Blondeaux & Seminara (1985). Indeed it is observed that upstream influence may occur only in relatively wide channels, while narrower stream…
Pair-bonding in birds and the active role of females: a critical review of the empirical evidence.
2000
Over the recent years the role of females in maintaining or breaking the pair-bond in socially monogamous birds has received growing attention. Here, we review the overall evidence for a direct and predominant role of female behaviour in initiating or preventing divorce and its relevance for the understanding of both interspecific and intraspecific variation in divorce rate in monogamous bird species. The evidence is so far limited to a few species. We discuss the relevance of some alternative explanations and confounding factors. We conclude that the possible predominance of females in both initiating divorce or limiting its occurrence deserves further consideration. Future studies should …
Binge Drinking: The Top 100 Cited Papers
2021
We conducted a review to analyze the 100 most-cited studies on binge drinking (BD) in the Web of Science (WoS) database to determine their current status and the aspects that require further attention. We carried out a retrospective bibliometric analysis in January 2021. The year of publication, authors, design, subject, journal, institution and lead author’s country, as well as the definition of BD, were extracted from the articles. The data on the country, year, thematic category of the journals and their rank were obtained from the Institute for Scientific Information (ISI) Journal Citation Reports 2020. The number of citations was collected from the WoS, and the h index was collected fr…
The evolution of parental care in insects: the roles of ecology, life history and the social environment
2013
Parental care increases the fitness of offspring at a cost to the parents in terms of residual reproductive success. This trade-off may be affected by ecology, life history and the social environment, which raises the question as to how these factors contribute to the evolution of parental care. Here, previous hypotheses concerning the evolution of parental care in insects are summarized and discussed and the underlying empirical evidence is reviewed. Ecological factors such as harsh environments, ephemeral food sources or predation pressure are broadly accepted as evolutionary drivers of parental care. The most consistent evidence supports a role for natural enemies such as predators, micr…
Stabilization of Polar Step Edges on Calcite (10.4) by the Adsorption of Congo Red
2015
In this work, we present the stabilization of polar step edges along the [010] direction of calcite (10.4) by the presence of a water-soluble organic molecule, namely Congo Red. While characteristic etch pits are observed on the surface in the absence of the additive, no etch pits can be found in the presence of the additive. Using atomic force microscopy, we can directly follow the restructuring of the surface. Upon addition of Congo Red, the charge-neutral step edges confining the characteristic etch pits vanish, while polar step edges along the [010] direction appear on the surface, which are entirely decorated by well-ordered molecular islands of the additive. After the restructuring ha…
Calendar Anomalies in Stock Index Futures
2011
There exist a large and increasing number of papers that describe different calendar anomalies in stock markets. Although empirical evidence suggests that seasonal effects disappeared after the early 1990s, new studies and approaches assert the continuation of some anomalies in stock indexes. In this paper, we present a comprehensive study of 188 possible cyclical anomalies in S&P 500, DAX and Nikkei stock index futures contracts from 1991 to 2008. Frictions in futures markets, unlike spot markets frictions, make it feasible to produce economically significant profits from trading rules based on calendar effects. By applying a percentile-t-bootstrap and Monte Carlo methods, our analysis rev…
The analysis of 51 genes in DSM-IV combined type attention deficit hyperactivity disorder: association signals in DRD4, DAT1 and 16 other genes.
2006
Contains fulltext : 35205.pdf (Publisher’s version ) (Closed access) Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder, starting in early childhood and persisting into adulthood in the majority of cases. Family and twin studies have demonstrated the importance of genetic factors and candidate gene association studies have identified several loci that exert small but significant effects on ADHD. To provide further clarification of reported associations and identify novel associated genes, we examined 1,038 single-nucleotide polymorphisms (SNPs) spanning 51 candidate genes involved in the regulation of neurotransmitter pathways, particularly dopamine, nor…