Showing papers by "Université du Québec à Montréal published in 2005"

Information and its use by animals in evolutionary ecology

Abstract: Information is a crucial currency for animals from both a behavioural and evolutionary perspective. Adaptive behaviour relies upon accurate estimation of relevant ecological parameters; the better informed an individual, the better it can develop and adjust its behaviour to meet the demands of a variable world. Here, we focus on the burgeoning interest in the impact of ecological uncertainty on adaptation, and the means by which it can be reduced by gathering information, from both 'passive' and 'responsive' sources. Our overview demonstrates the value of adopting an explicitly informational approach, and highlights the components that one needs to develop useful approaches to studying information use by animals. We propose a quantitative framework, based on statistical decision theory, for analysing animal information use in evolutionary ecology. Our purpose is to promote an integrative approach to studying information use by animals, which is itself integral to adaptive animal behaviour and organismal biology.

Edge Influence on Forest Structure and Composition in Fragmented Landscapes

Abstract: Although forest edges have been studied extensively as an important consequence of fragmenta- tion, a unifying theory of edge influence has yet to be developed. Our objective was to take steps toward the development of such a theory by (1) synthesizing the current knowledge of patterns of forest structure and composition at anthropogenically created forest edges, (2) developing hypotheses about the magnitude and distance of edge influence that consider the ecological processes influencing these patterns, and (3) identifying needs for future research. We compiled data from 44 published studies on edge influence on forest structure and composition in boreal, temperate, and tropical forests. Abiotic and biotic gradients near created forest edges generate a set of primary responses to edge creation. Indirect effects from these primary responses and the original edge gradient perpetuate edge influence, leading to secondary responses. Further changes in veg- etation affect the edge environment, resulting in ongoing edge dynamics. We suggest that the magnitude and distance of edge influence are a direct function of the contrast in structure and composition between adjacent communities on either side of the edge. Local factors such as climate, edge characteristics, stand attributes, and biotic factors affect patch contrast. Regional factors define the context within which to assess the ecological significance of edge influence (the degree to which the edge habitat differs from interior forest habitat). Our hypotheses will help predict edge influence on structure and composition in forested ecosystems, an important consideration for conservation. For future research on forest edges in fragmented landscapes, we encourage the testing of our hypotheses, the use of standardized methodology, complete descriptions of study sites, studies on other types of edges, synthesis of edge influence on different components of the ecosystem, and investigations of edges in a landscape context.

Environmental disclosure quality in large German companies: Economic incentives, public pressures or institutional conditions?

Abstract: Investors and stakeholders in continental Europe are becoming increasingly concerned about corporate environmental policies. As a result, many firms are voluntarily increasing the extent of their environmental disclosure in their annual report. While mostly unregulated, corporate environmental disclosure does have potential economic significance considering the scarcity of alternative information sources. The purpose of this study is to identify determinants of corporate environmental disclosure using multi-theoretical lenses that rely on economic incentives, public pressures and institutional theory. The study focuses on large firms from a continental Europe country, Germany, with a distinct legal and regulatory context and where environmental concerns are especially acute. Results show that Risk, Ownership, Fixed Assets Age, Firm Size as well as routine determine the level of environmental disclosure by German firms in a given year. Moreover, consistent with institutional theory, results sugge...

Distribution of Typical Freshwater Bacterial Groups Is Associated with pH, Temperature, and Lake Water Retention Time

Abstract: The distribution of 15 typical freshwater bacterial groups in 15 diverse lakes in northern Europe was investigated using reverse line blot hybridization. Statistical evaluation of the data in relation to the characteristics of the lakes showed that pH, temperature, and the theoretical hydrological retention time of the lakes were most strongly related to variations in the distribution of bacterial taxa. This suggests that pH and temperature are steering factors in the selection of taxa and supports the notion that communities in lakes with short water turnover times are influenced by the input of bacterial cells from the drainage areas. Within the beta subdivision of the Proteobacteria (Betaproteobacteria), as well as within the divisions Actinobacteria and Verrucomicrobia, different subgroups were associated differently with environmental variables.

Bringing humility to leadership: Antecedents and consequences of leader humility:

Abstract: As noted by McGill and Slocum (1998), effective leadership tends to operate as a contingency theory. The romanticized notion of celebrity CEOs that has been lionized in the popular business press has its place in the leadership pantheon, but, like any other approach to leadership, has limitations in its application. In particular, as discussed by Collins (2001a), sustained organizational functioning is more likely to be the result of the celebrity’s antithesis, a person possessing a blend of humility and strong personal will. This article draws from a diversity of sources in order to explore this potential nexus between humility and leadership. It offers a precise conceptualization of the concept of humility, identifies traits that are predictors of humility as well as the specific leadership behaviors that are likely to be the outcomes of high levels of humility.

Coupled nitrogen and oxygen isotope measurements of nitrate along the eastern North Pacific margin

Abstract: [1] Water column depth profiles along the North Pacific margin from Point Conception to the tip of Baja California indicate elevation of nitrate (NO3−) 15N/14N and 18O/16O associated with denitrification in the oxygen-deficient thermocline waters of the eastern tropical North Pacific. The increase in δ18O is up to 3‰ greater than in δ15N, whereas our experiments with denitrifier cultures in seawater medium indicate a 1:1 increase in NO3− δ18O and δ15N during NO3− consumption. Moreover, the maximum in NO3− δ18O is somewhat shallower than the maximum in NO3− δ15N. These two observations can be summarized as an “anomaly” from the 1:1 δ18O-to-δ15N relationship expected from culture results. Comparison among stations and with other data indicates that this anomaly is generated locally. The anomaly has two plausible interpretations: (1) the addition of low-δ15N NO3− to the shallow thermocline by the remineralization of newly fixed nitrogen, or (2) active cycling between NO3− and NO2− (coupled NO3− reduction and NO2− oxidation) in the suboxic zone.

Electrochemical derivatization of carbon surface by reduction of in situ generated diazonium cations.

Abstract: The derivatization of a glassy carbon electrode surface was achieved by electrochemical reduction of several in situ generated diazonium cations. The diazonium cations were synthesized in the electrochemical cell by reaction of the corresponding amines with NaNO2 in aqueous HCl. The versatility of the method was demonstrated by using six diazonium cations. This deposition method, which involves simple reagents and does not require the isolation and purification of the diazonium salt, enabled the grafting of covalently bounded layers which exhibited properties very similar to those of layers obtained by the classical derivatization method involving isolated diazonium salt dissolved in acetonitrile or aqueous acid solution. Cyclic voltammetry and electrochemical impedance spectroscopy carried out in aqueous solutions containing electroactive redox probe molecules such as Fe(CN)63-/4- and Ru(NH3)63+ confirmed the barrier properties of the deposited layers. The chemical composition of the grafted layers was d...

Prevalence of Heterotrophy and Atmospheric CO2 Emissions from Aquatic Ecosystems

Abstract: Recent, parallel developments in the study of freshwater and marine ecosystems have provided evidence that net heterotrophic systems (those in which respiratory organic matter destruction exeeds photosynthetic production) are more prevalent than hitherto believed, including most rivers, oligo- to mesotrophic lakes and some oligotrophic regions of the ocean. In parallel, these aquatic ecosystems have been shown to act as CO2 sources to the atmosphere, as expected from the heterotrophic nature of the communities they contain. The prevalence of net heterotrophic aquatic ecosystems indicates that they must receive significant inputs of organic carbon from adjacent ecosystems, assigning an important role to the lateral exchanges of carbon between land and aquatic ecosystems, between coastal and open ocean ecosystems, as well as internal redistribution within large or complex aquatic ecosystems in determining their metabolic status and the gaseous exchange with the atmosphere. The examination of the carbon budget of ecosystems requires, therefore, an integrative approach that accounts for exchanges between compartments often studied in isolation. These recent findings conform a new paradigm of the functioning of aquatic ecosystems, and the metabolic connectivity between ecosystems in the biosphere.

Internet versus Bricks-and-Mortar Retailers: An Investigation into Intangibility and Its Consequences

Abstract: Intangibility has long been studied as a unidimensional construct with the focus being placed upon the physical element. This paper explores the effects of three unique intangibility dimensions on a consumer’s ability to evaluate goods and services, and the perceived risk (PR) associated with the transaction. The authors examine these relationships in purchase environments that include both traditional bricks-and-mortar retailers and the Internet. Their investigation further incorporates prior knowledge as a moderating factor into the proposed framework. This allows for a thorough comparison of the effects and relationships that exist between intangibility and its consequences in general, evaluation difficulty (ED) and perceived risk (PR) in particular. The authors develop hypotheses pertaining to the proposed model and test them with two experiments. The empirical results are broadly supportive of the hypotheses. Theoretical and managerial implications to the services marketing literature are discussed.

Training Effects on Dual-Task Performance: Are There Age-Related Differences in Plasticity of Attentional Control?

Abstract: A number of studies have suggested that attentional control skills required to perform 2 tasks concurrently become impaired with age (A. A. Hartley, 1992; J. M. McDowd & R. J. Shaw, 2000). A. A. Hartley (2001) recently observed that the age-related differences in dual-task performance were larger when the 2 tasks required similar motor responses. The present study examined the extent to which age-related deficits in dual-task performance or time sharing--in particular, dual-task performance of 2 discrimination tasks with similar motor requirements--can be moderated by training. The results indicate that, even when the 2 tasks required similar motor responses, both older and younger adults could learn to perform the tasks faster and more accurately. Moreover, the improvement in performance generalized to new task combinations involving new stimuli. Therefore, it appears that training can substantially improve dual-task processing skills in older adults.

Currents in Environmental Education: Mapping a Complex and Evolving Pedagogical Field.

Abstract: The purpose of this article is to bring to light and celebrate the richness of the environmental education field, thereby paying homage to the pedagogical creativity of its architects over the course of the last thirty years, as well as to their contribution in reflecting on the meaning, problems and possibilities of our relationship to the environment, and on the role of education in this regard. A typology of the different practical and theoretical propositions is presented, in the form of 15 currents of intervention, enabling a mapping of the pedagogical landscape of environmental education. This cartography offers points of reference for critical analysis of discourses and practices in this educational field. It spreads out a rich diversity of inspiration sources for enriching programs or curricula and for conceiving appropriate strategies. Resume Cet article a pour but de mettre en lumiere et de celebrer la richesse du champ de l’education relative a l’environnement, rendant ainsi hommage a la creativite pedagogique de ses artisans au fil des trente dernieres annees et a leur effort de reflexion sur le sens de notre rapport a l’environnement et sur le role de l’education a cet effet. Une typologie des differentes propositions theoriques et pratiques, sous forme de 15 courants d’intervention, permet de tracer une carte du territoire pedagogique de l’education relative a l’environnement et d’apprecier l’ampleur et la diversite du domaine. Cette typologie offre des reperes favorisant l’analyse critique des discours et des situations educatives; elle se deploie comme un ensemble de sources d’inspiration pour l’enrichissement des programmes ou curriculums et pour la conception de strategies appropriees. An overview of the literature in the field of environmental education shows that, despite their shared concern for the environment and their recognition of the central role of education in enhancing human-environment relationships, various authors (researchers, professors, educators, facilitators, associations, organizations, etc.) adopt widely differing discourses on environmental education, and propose diverse ways of practicing educative activity in this field. Each advocates his or her own vision—we may even identify different pedagogical “chapels,” all distinct proponents of the right approach, the best program, the appropriate method. How can we orient ourselves amid such a diversity of propositions? How can we discern which voice(s) should inspire our own educational initiatives?

Characterization of the deposition of organic molecules at the surface of gold by the electrochemical reduction of aryldiazonium cations.

Abstract: The deposition of 4-X phenyl groups (X = NO2, COOH, N-(C2H5)2) on polycrystalline gold electrode was achieved by the electrochemical reduction of the corresponding 4-substituted phenyldiazonium tetrafluoroborate salts in anhydrous acetonitrile media. The electrochemical quartz crystal microbalance measurements evidenced a two-step deposition process: the first one is the deposition of close to a monolayer and the second one is the relatively slower growth of multilayers. In this second region, the deposition is less efficient than for the first one. The electrochemical behavior of the resulting modified gold electrode was investigated in the presence of an electroactive redox probe and these results, together with the electrochemical quartz crystal microbalance data, demonstrated significant differences in reactivity and in deposition efficiency between the diazonium salts. The characterization of the modified electrodes by cyclic voltammetry and electrochemical impedance spectroscopy, as well as X-ray photoelectron spectroscopy measurements, showed that the formation of multilayers is possible and that a significant fraction of the deposited material remained at the electrode surface, even following ultrasonic treatment. The X-ray photoelectron spectroscopy data indicate that the existence of Au-C and Au-N=N-C linkages (where C represents a carbon atom of the phenyl group) is uncertain. Nonetheless, the deposition of the aryl groups by electrochemical reduction of diazonium cations yielded a film that adheres well to the gold surface and the deposited organic film hindered gold oxides formation in acidic medium.

Ten-Year Cross-Disciplinary Comparison of the Growth of Open Access and How it Increases Research Citation Impact

Abstract: In 2001, Lawrence found that articles in computer science that were openly accessible (OA) on the Web were cited substantially more than those that were not. We have since replicated this effect in physics. To further test its cross-disciplinary generality, we used 1,307,038 articles published across 12 years (1992-2003) in 10 disciplines (Biology, Psychology, Sociology, Health, Political Science, Economics, Education, Law, Business, Management). We designed a robot that trawls the Web for full-texts using reference metadata (author, title, journal, etc.) and citation data from the Institute for Scientific Information (ISI) database. A preliminary signal-detection analysis of the robot's accuracy yielded a signal detectability d'=2.45 and bias = 0.52. The overall percentage of OA (relative to total OA + NOA) articles varies from 5%-16% (depending on discipline, year and country) and is slowly climbing annually (correlation r=.76, sample size N=12, probability p .90, N=12, p < .0005) and the effect is greater with the more highly cited articles (r = .98, N=6, p < .005). Causality cannot be determined from these data, but our prior finding of a similar pattern in physics, where percent OA is much higher (and even approaches 100% in some subfields), makes it unlikely that the OA citation advantage is merely or mostly a self-selection bias (for making only one's better articles OA). Further research will analyze the effect's timing, causal components and relation to other variables, such as, download counts, journal citation averages, article quality, co-citation measures, hub/authority ranks, growth rate, longevity, and other new impact measures generated by the growing OA database.

Arrival rate of nonindigenous insect species into the United States through foreign trade.

Abstract: Introductions of invasive nonindigenous species, and the ensuing negative ecological and economic consequences, have increased with expanding global trade. Quantifying the influx of nonindigenous plant pest species through foreign trade is required for national and international risk assessments, monitoring and conservation efforts, and evaluation of ecological factors that affect invasion success. Here we use statistically robust data collected at US ports of entry and border crossings to estimate arrival rates of nonindigenous insect species via four cargo pathways and to evaluate the effectiveness of current efforts to monitor arrival of nonindigenous insect species. Interception rates were highest in refrigerated maritime cargo where a new insect species was intercepted on average every 54 inspections. Projected estimates of insect species richness stabilized only for non-refrigerated maritime cargo and US–Mexico border cargo, where inspectors likely detected 19–2% and 30–50% of the species being transported through these respective pathways. Conservative estimates of establishment suggest that 42 insect species may have become established through these four pathways between 1997 and 2001.

Aerospace Clusters: Local or Global Knowledge Spillovers?

Abstract: The literature about regional innovation systems, clusters and industrial districts insists on the importance of local knowledge spillovers. Nevertheless, more recently a few authors have put in question the importance of local knowledge spillovers. This paper provides an analysis of some of the most dynamic aerospace clusters in the world, located in Montreal, Seattle, Toulouse and Toronto. We start by discussing theories of clustering, then provide research questions as well as empirical evidence on the international nature of knowledge spillovers. Local knowledge spillovers are less significant, of a different nature, and they may make a scanty contribution to explain the geographical agglomeration of firms. Conversely, international spillovers help to explain the relative dispersion of industry across nations. Resilient geographical clustering is related to the anchor tenant effects as creators of labour pools and owners of very large manufacturing plants creating regional inertia. We thus reject the ...

Does supporting employees' career adaptability lead to commitment, turnover, or both?

Abstract: Today, employees are encouraged to become more career-resilient and engage in career development activities to deal with changes in required knowledge, skills, and abilities, and to facilitate their mobility. This study found that participation in decision making (PDM) and autonomy, along with supervisory career support (information, advice, and encouragement), fostered this career adaptability. These practices were also positively associated with commitment and negatively with intentions to leave. However, career adaptability was positively associated with both commitment and intentions to leave, suggesting some unintended consequences for management approaches supporting career adaptability. Implications for research and practice are discussed. © 2005 Wiley Periodicals, Inc.

Governance Regimes for Large Complex Projects

Abstract: This paper presents a framework for building governance regimes for large complex projects. The framework is based on three sources: 1) a re-examination of a study of 60 large capital projects (Mil...

Passion and Gambling: Investigating the Divergent Affective and Cognitive Consequences of Gambling1

Abstract: Vallerand et al (2003) developed a theoretical framework of passion where two types of passions are proposed: obsessive and harmonious passion Obsessive passion is characterized by an internal pressure that pushes the person to engage in the passionate activity, whereas harmonious passion is characterized by the person’s choice to engage in the activity The goal of the present study was to examine the outcomes of these types of passion toward gambling A total of 554 participants completed instruments assessing their passion toward gambling, as well as several cognitive and affective outcomes Results indicated that, in general, harmonious passion was associated with positive outcomes, while obsessive passion was related to negative consequences Results also showed that casino activities accentuated both positive and negative outcomes by fostering both types of passion toward the gambling activity Conceptual and practical implications are discussed

To Cognize is to Categorize: Cognition is Categorization

Abstract: We organisms are sensorimotor systems. The things in the world come in contact with our sensory surfaces, and we interact with them based on what that sensorimotor contact “affords”. All of our categories consist in ways we behave differently toward different kinds of things -- things we do or don’t eat, mate-with, or flee-from, or the things that we describe, through our language, as prime numbers, affordances, absolute discriminables, or truths. That is all that cognition is for, and about.

Who may frown and who should smile? Dominance, affiliation, and the display of happiness and anger

Abstract: Three experiments were conducted to test the hypothesis that the social stereotype that anger displays are more appropriate for men and smiling is requisite for women is based on the perception of men and women as more or less dominant or affiliative. The first study tested the mediation model that men are rated as more dominant and women as more affiliative and that expectations for men to show more anger and for women to smile more are partially mediated by this difference in perception. Second, a vignette approach was used to test the notion that these expectations translate into prescriptive social norms that are based on levels of perceived dominance and affiliation rather than sex per se. The results strongly support this hypothesis for dominance and provide partial confirmation for affiliation.

Indirect Networks: An Intangible Resource for Biotechnology Innovation

Abstract: In the context of the emergence of new modular organizational forms, especially in high-tech sectors such as the biotechnology sector, this article proposes that while a firm observes benefits from direct alliances, it also benefits from indirect linkages. First, a theoretical framework revolving around indirect ties is built on the basis of social network and innovation management literature. It ends with the proposition of two research hypotheses linking the indirect network position of a firm to its innovation capacities. To test those hypotheses, data on strategic partnerships and collaborations were collected through 40 interviews with biotech firms from the nutrition sector in the biotech clusters of Quebec (Canada). Using network analysis, centrality measures and hierarchical regressions, results of this study indicate that by occupying a central position in a network of indirect ties, a firm is more likely to access useful knowledge from its direct partners and increase innovation. We suggest, as a conclusion, that indirect network position could be considered as an intangible strategic resource for biotech firms.

Relations with parents and with peers, temperament, and trajectories of depressed mood during early adolescence.

Abstract: The present study examined (a) whether groups of children can be empirically identified with distinct longitudinal profiles of depressed mood from late childhood through early adolescence, (b) to what extent these different longitudinal depression profiles are predicted by problematic relations with parents, same-sex peers, and other-sex peers, and (c) what role individuals' temperamental characteristics play in this context. Based on a sample of 414 early adolescents (197 girls), four groups were identified with distinct longitudinal profiles of depressed mood between ages 11 and 14: One group with consistently low levels of depressed mood, another with consistently moderate levels of depressed mood, a third group whose depressed mood increased sharply from late childhood through early adolescence, and a fourth group who already showed clinical-range levels of depressed mood during late childhood and whose depressive feelings increased even slightly more thereafter. Subsequent analyses revealed that rejection by same-sex peers was related to the odds of following an increasing trajectory of depressed mood, but only for girls with a highly reactive temperament. A problematic relationship with parents increased the odds of an elevated trajectory of depressed mood regardless of individual temperament. The theoretical and practical implications of these findings are discussed.