Search results for "heterogeneity"
showing 10 items of 402 documents
Connecting others: Does a tertius iungens orientation shape the relationship between research networks and innovation?
2021
Research on social networks and innovation emphasizes that individuals spanning structural holes and crossing institutional boundaries have more opportunities for knowledge recombination and innovation involvement. However, transforming the potential knowledge and resources available through personal networks to attain innovation can be difficult for the focal individual. Using an ego-network approach, this study examines whether and to what extent an individual strategic orientation to cooperation (i.e. tertius iungens) contributes to strengthening the relation between two personal network properties (structural and institutional separation) and involvement in innovation. Our analysis is c…
Heterogeneity versus Homogeneity in Schools: A Review of the Educational Value of Classroom Interaction
2020
The degree of homogeneity and heterogeneity among schools affects the comprehensiveness and inclusiveness of the school system and the type and scope of classroom interaction. Since the beginning of the 1980s, interest has gradually increased in the effects of homogeneity and heterogeneity of schools on classroom interactions
Hétérogénéité spatiale : principes et méthodes
2004
Spatial Heterogeneity : Principles and Methods This article has a dual purpose . First , it describes the main econometric specifications which can be used to represent spatial heterogeneity , reflected in an instability of parameters in space and / or a heteroscedasticity of error terms . Only the specifications valid in cross-section are examined . Second , it explains the links between spatial heterogeneity and autocorrelation , the other major feature of localised data , defined by the absence of independence between geographical observations . In particular , we look at the extent to which traditional tests of heteroscedasticity or instability need to be amended to take account of spat…
Management diversification increases habitat availability for multiple biodiversity indicator species in production forests
2022
Context Forest biodiversity is closely linked to habitat heterogeneity, while forestry actions often cause habitat homogenization. Alternative approaches to even-aged management were developed to restore habitat heterogeneity at the stand level, but how their application could promote habitat diversity at landscape scale remains uncertain. Objectives We tested the potential benefit of diversifying management regimes to increase landscape-level heterogeneity. We hypothesize that different styles of forest management would create a diverse mosaic of forest habitats that would in turn benefit species with various habitat requirements. Methods Forest stands were simulated under business-as-usua…
Genetic relationship between clinical and environmental Vibrio cholerae isolates in Tanzania: A comparison using repetitive extragenic palindromic (R…
2015
The bacterium causing cholera, Vibrio cholerae, is a marine organism and coastal waters are important reservoirs of the organism. There are more than 200 serogroups of V. cholerae, of which serogroups O1 and O139 are known to be the causative agent of the cholera. The main virulent factor in V. cholerae is cholera toxin gene (ctx) that is found from the epidemic O1 and O139 strains, but may also be found in some strains other than O1 and O139 (non-O1 and non-O139). In this study, 48 V. cholerae strains isolated from three estuaries of Tanzania and 20 stool isolates were characterized in terms of their serogroups and possession of ctx gene and then compared using two PCR based fingerprinting…
How news affect the trading behavior of different categories of investors in a financial market
2015
We investigate the trading behavior of a large set of single investors trading the highly liquid Nokia stock over the period 2003-2008 with the aim of determining the relative role of endogenous and exogenous factors that may affect their behavior. As endogenous factors we consider returns and volatility, whereas the exogenous factors we use are the total daily number of news and a semantic variable based on a sentiment analysis of news. Linear regression and partial correlation analysis of data show that different categories of investors are differently correlated to these factors. Governmental and non profit organizations are weakly sensitive to news and returns or volatility, and, typica…
Variants of human CLDN9 cause mild to profound hearing loss
2021
Hereditary deafness is clinically and genetically heterogeneous. We investigated deafness segregating as a recessive trait in two families. Audiological examinations revealed an asymmetric mild to profound hearing loss with childhood or adolescent onset. Exome sequencing of probands identified a homozygous c.475G>A;p.(Glu159Lys) variant of CLDN9 (NM_020982.4) in one family and a homozygous c.370_372dupATC;p.(Ile124dup) CLDN9 variant in an affected individual of a second family. Claudin 9 (CLDN9) is an integral membrane protein and constituent of epithelial bicellular tight junctions that form semi-permeable, paracellular barriers between inner ear perilymphatic and endolymphatic compartment…
Is personality related to permanent earnings? Evidence using a twin design
2018
Using twin survey combined with register-based panel data on labor market outcomes, the authors examine the association between personality characteristics and long-term earnings among prime working-age individuals. The long-term earnings were measured over the 1990–2008 period. The sample contains 4,642 twin pairs, of which 53% are females. In contrast to previous studies, this paper uses the within-twin dimension of the data to control for shared family background and confounding genetic factors. The results suggest that unobserved genetic differences may introduce omitted variable bias in standard ordinary least square results. After controlling for shared environment and genetic backgro…
Assessing the conservation priority of freshwater lake sites based on taxonomic, functional and environmental uniqueness
2022
Aim We propose a novel approach that considers taxonomic uniqueness, functional uniqueness and environmental uniqueness and show how it can be used in guiding conservation planning. We illustrate the approach using data for lake biota and environment. Location Lake Puruvesi, Finland. Methods We sampled macrophytes and macroinvertebrates from the same 18 littoral sites. By adapting the original “ecological uniqueness” approach, we used distance-based methods to calculate measures of taxonomic (LCBD–t), functional (LCBD–f) and environmental (LCEH) uniqueness for each site. We also considered the numbers and locations of the sites needed to protect up to 70% of total variation in taxonomic, fu…