Showing papers by "Université du Québec à Montréal published in 2003"
TL;DR: Results from four studies involving more than 900 participants from different populations supported the proposed conceptualization of two types of passion: obsessive and harmonious.
Abstract: Passion is defined as a strong inclination toward an activity that people like, that they find important, and in which they invest time and energy Two types of passion are proposed: obsessive and harmonious Obsessive passion (OP) refers to a controlled internalization of an activity in one's identity that creates an internal pressure to engage in the activity that the person likes Harmonious passion (HP) refers to an autonomous internalization that leads individuals to choose to engage in the activity that they like HP promotes healthy adaptation whereas OP thwarts it by causing negative affect and rigid persistence Results from four studies involving more than 900 participants from different populations supported the proposed conceptualization
1,726 citations
TL;DR: A motivational model of the coach–athlete relationship is presented that describes how coaches may influence athletes' motivation and the psychological processes through which coaching behaviours have a positive influence on athletes' intrinsic and self-determined extrinsic motivation.
Abstract: The aim of this paper is to present a motivational model of the coach–athlete relationship that describes how coaches may influence athletes' motivation. In line with cognitive evaluation theory (D...
1,136 citations
TL;DR: In this article, LiDAR data is used to estimate the canopy height of a single tree in a forest and to model the above-ground biomass and canopy volume of the forest.
Abstract: Light detection and ranging (LiDAR) technology provides horizontal and vertical information at high spatial resolutions and vertical accuracies. Forest attributes such as canopy height can be directly retrieved from LiDAR data. Direct retrieval of canopy height provides opportunities to model above-ground biomass and canopy volume. Access to the vertical nature of forest ecosystems also offers new opportunities for enhanced forest monitoring, management and planning.
1,046 citations
TL;DR: Evidence is presented that the attenuated vesicular stomatitis strains, AV1 and AV2, embody all of the traits of an oncolytic virus, which will replicate preferentially in malignant cells, have the ability to treat disseminated metastases, and ultimately be cleared by the patient.
830 citations
TL;DR: In this paper, the determinants of corporate environmental reporting using a cost/benefit framework within France's unique legal and regulatory context were investigated, concluding that proprietary costs, information costs, and media visibility determine corporate reporting.
622 citations
TL;DR: In this paper, it was shown that the g value derived from delayed L i / T i measurements is strongly dependent on the timing of the preheat treatment, which can be used to correct the measured optical ages.
606 citations
TL;DR: The authors examined the relationship between CEO incentives and strong and weak corporate social performance using the KLD database and found that incentives have no significant relationship with strong social performance and that long-term incentives have a positive association with weak social performance.
Abstract: This paper examines the relationship between CEO incentives and strong and weak corporate social performance Using the KLD database we find that incentives have no significant relationship with strong social performance Salary and long-term incentives have a positive association with weak social performance
403 citations
TL;DR: Some ways that gender can be and has been handled in studies of occupational health, as well as some of the consequences, are described and specific research practices that avoid errors are suggested.
Abstract: Background Both women's and men's occupational health problems merit scientific attention. Researchers need to consider the effect of gender on how occupational health issues are experienced, expressed, defined, and addressed. More serious consideration of gender-related factors will help identify risk factors for both women and men. Methods The authors, who come from a number of disciplines (ergonomics, epidemiology, public health, social medicine, community psychology, economics, sociology) pooled their critiques in order to arrive at the most common and significant problems faced by occupational health researchers who wish to consider gender appropriately. Results This paper describes some ways that gender can be and has been handled in studies of occupational health, as well as some of the consequences. The paper also suggests specific research practices that avoid errors. Obstacles to gender-sensitive practices are considered. Conclusions Although gender-sensitive practices may be difficult to operationalize in some cases, they enrich the scientific quality of research and should lead to better data and ultimately to well-targeted prevention programs. ⌐ 2003 Wiley-Liss, Inc.
366 citations
TL;DR: It is suggested that TaVRT-1 is a key developmental gene in the regulatory pathway that controls the transition from the vegetative to reproductive phase in cereals.
Abstract: The molecular genetics of vernalization, defined as the promotion of flowering by cold treatment, is still poorly understood in cereals. To better understand this mechanism, we cloned and characterized a gene that we named TaVRT-1 (wheat [Triticum aestivum] vegetative to reproductive transition-1). Molecular and sequence analyses indicated that this gene encodes a protein homologous to the MADS-box family of transcription factors that comprises certain flowering control proteins in Arabidopsis. Mapping studies have localized this gene to the Vrn-1 regions on the long arms of homeologous group 5 chromosomes, regions that are associated with vernalization and freezing tolerance (FT) in wheat. The level of expression of TaVRT-1 is positively associated with the vernalization response and transition from vegetative to reproductive phase and is negatively associated with the accumulation of COR genes and degree of FT. Comparisons among different wheat genotypes, near-isogenic lines, and cereal species, which differ in their vernalization response and FT, indicated that the gene is inducible only in those species that require vernalization, whereas it is constitutively expressed in spring habit genotypes. In addition, experiments using both the photoperiod-sensitive barley (Hordeum vulgare cv Dicktoo) and short or long day de-acclimated wheat revealed that the expression of TaVRT-1 is also regulated by photoperiod. These expression studies indicate that photoperiod and vernalization may regulate this gene through separate pathways. We suggest that TaVRT-1 is a key developmental gene in the regulatory pathway that controls the transition from the vegetative to reproductive phase in cereals.
351 citations
TL;DR: In this article, a size-segregated multicomponent aerosol algorithm, the Canadian Aerosol Module (CAM), was developed for use with climate and air quality models.
Abstract: A size-segregated multicomponent aerosol algorithm, the Canadian Aerosol Module (CAM), was developed for use with climate and air quality models. It includes major aerosol processes in the atmosphere: generation, hygroscopic growth, coagulation, nucleation, condensation, dry deposition/sedimentation, below-cloud scavenging, aerosol activation, a cloud module with explicit microphysical processes to treat aerosol-cloud interactions and chemical transformation of sulphur species in clear air and in clouds. The numerical solution was optimized to efficiently solve the complicated size-segregated multicomponent aerosol system and make it feasible to be included in global and regional models. An internal mixture is assumed for all types of aerosols except for soil dust and black carbon which are assumed to be externally mixed close to sources. To test the algorithm, emissions to the atmosphere of anthropogenic and natural aerosols are simulated for two aerosol types: sea salt and sulphate. A comparison was made of two numerical solutions of the aerosol algorithm: process splitting and ordinary differential equation (ODE) solver. It was found that the process-splitting method used for this model is within 15% of the more accurate ODE solution for the total sulphate mass concentration and <1% accurate for sea-salt concentration. Furthermore, it is computationally more than 100 times faster. The sensitivity of the simulated size distributions to the number of size bins was also investigated. The diffusional behavior of each individual process was quantitatively characterized by the difference in the mode radius and standard deviation of a lognormal curve fit of distributions between the approximate solution and the 96-bin reference solution. Both the number and mass size distributions were adequately predicted by a sectional model of 12 bins in many situations in the atmosphere where the sink for condensable matter on existing aerosol surface area is high enough that nucleation of new particles is negligible. Total mass concentration was adequately simulated using lower size resolution of 8 bins. However, to properly resolve nucleation mode size distributions and minimize the numerical diffusion, a sectional model of 18 size bins or greater is needed. The number of size bins is more important in resolving the nucleation mode peaks than in reducing the diffusional behavior of aerosol processes. Application of CAM in a study of the global cycling of sea-salt mass accompanies this paper
291 citations
TL;DR: Drug dissolution kinetics showed longer release times for higher degrees of functionalization, suggesting palmitoyl chitosan excipients as interesting candidates for oral and subdermal pharmaceutical applications.
TL;DR: Data suggest that bone‐marrow‐derived stromal cells may have the capacity to participate in tumor angiogenesis through regulation of their angiogenic properties under an atmosphere of low oxygen that closely approximates the tumor microenvironment.
Abstract: Recent evidence indicates that bone-marrow-derived stromal cells (MSCs) have a histology coherent with endothelial cells that may enable them to contribute to tumor angiogenesis through yet undefined mechanisms. In this work, we investigated the angiogenic properties of murine MSCs involved in extracellular matrix degradation and in neovascularization that could take place in a hypoxic environment such as that encountered in tumor masses. MSCs were cultured in normoxia (95% air and 5% CO(2)) or in hypoxia (1% oxygen, 5% CO(2), and 94% nitrogen). We found that hypoxic culture conditions rapidly induced MSC migration and three-dimensional capillary-like structure formation on Matrigel. In vitro, MSC migration was induced by growth-factor- and cytokine-enriched conditioned media isolated from U-87 glioma cells as well as from MSCs cultured in hypoxic conditions, suggesting both paracrine and autocrine regulatory mechanisms. Although greater vascular endothelial growth factor levels were secreted by MSCs in hypoxic conditions, this growth factor alone could not explain their greater migration. Interestingly, matrix metalloproteinase (MMP)-2 mRNA expression and protein secretion were downregulated, while those of membrane-type (MT)1-MMP were strongly induced by hypoxia. Functional inhibition of MT1-MMP by a blocking antibody strongly suppressed MSC ability to migrate and generate capillary-like structures. Collectively, these data suggest that MSCs may have the capacity to participate in tumor angiogenesis through regulation of their angiogenic properties under an atmosphere of low oxygen that closely approximates the tumor microenvironment.
TL;DR: The authors found that the welfare cost of consumption volatility per se is far from trivial and averages a substantial multiple of the corresponding U.S. estimate, and that in many poor countries, the welfare gain from eliminating volatility may in fact exceed the welfare gains from an additional percentage point of growth forever.
Abstract: Macroeconomic fluctuations are much stronger in developing countries than in the United States. Yet, while a large literature debates the welfare cost of economic fluctuations in the United States, it remains an open question how large that cost is in developing countries. Using several models, we provide such a measure. We find that the welfare cost of consumption volatility per se is far from trivial and averages a substantial multiple of the corresponding U.S. estimate. Moreover, in many poor countries, the welfare gain from eliminating volatility may in fact exceed the welfare gain from an additional percentage point of growth forever.
TL;DR: This work reports that VEGFR-2 is localized in endothelial caveolae, associated with caveolin-1, and that this complex is rapidly dissociated upon stimulation with VEGF, and observes that in an overexpression system in which VEG FR-1 is constitutively active, caveolin -1 overeexpression inhibits VEGfr-2 activity but allows VEGf-dependent activation, suggesting that caveolin can confer ligand dependency to a receptor system.
Abstract: The stimulation of vascular endothelial growth factor receptor-2 (VEGFR-2) by tumor-derived VEGF represents a key event in the initiation of angiogenesis In this work, we report that VEGFR-2 is localized in endothelial caveolae, associated with caveolin-1, and that this complex is rapidly dissociated upon stimulation with VEGF The kinetics of caveolin-1 dissociation correlated with those of VEGF-dependent VEGFR-2 tyrosine phosphorylation, suggesting that caveolin-1 acts as a negative regulator of VEGF R-2 activity Interestingly, we observed that in an overexpression system in which VEGFR-2 is constitutively active, caveolin-1 overexpression inhibits VEGFR-2 activity but allows VEGFR-2 to undergo VEGF-dependent activation, suggesting that caveolin-1 can confer ligand dependency to a receptor system Removal of caveolin and VEGFR-2 from caveolae by cholesterol depletion resulted in an increase in both basal and VEGF-induced phosphorylation of VEGFR-2, but led to the inhibition of VEGF-induced ERK activation and endothelial cell migration, suggesting that localization of VEGFR-2 to these domains is crucial for VEGF-mediated signaling Dissociation of the VEGFR-2/caveolin-1 complex by VEGF or cyclodextrin led to a PP2-sensitive phosphorylation of caveolin-1 on tyrosine 14, suggesting the participation of Src family kinases in this process Overall, these results suggest that caveolin-1 plays multiple roles in the VEGF-induced signaling cascade
TL;DR: In this paper, the authors presented a tectonic evolutionary model for the central segment of the Neoproterozoic Ribeira belt, southeastern Brazil, that can be subdivided in four major terranes: (a) the Occidental terrane, regarded as the reworked margin of the Sao Francisco Craton, to the northwest; (b) the Paraiba do Sul klippe; (c) the Oriental terrane comprising arc complexes, and (d) the Cabo Frio terrane to the southeast.
TL;DR: The idea that wt M protein suppresses interferon gene expression through the general inhibition of host RNA and protein synthesis is supported.
Abstract: The vesicular stomatitis virus (VSV) matrix (M) protein plays a major role in the virus-induced inhibition of host gene expression. It has been proposed that the inhibition of host gene expression by M protein is responsible for suppressing activation of host interferon gene expression. Most wild-type (wt) strains of VSV induce little if any interferon gene expression. Interferon-inducing mutants of VSV have been isolated previously, many of which contain mutations in their M proteins. However, it was not known whether these M protein mutations were responsible for the interferon-inducing phenotype of these viruses. Alternatively, mutations in other genes besides the M gene may enhance the ability of VSV to induce interferons. These hypotheses were tested by transfecting cells with mRNA expressing wt and mutant M proteins in the absence of other viral components and determining their ability to inhibit interferon gene expression. The M protein mutations were the M51R mutation originally found in the tsO82 and T1026R1 mutant viruses, the double substitution V221F and S226R found in the TP3 mutant virus, and the triple substitution E213A, V221F, and S226R found in the TP2 mutant virus. wt M proteins suppressed expression of luciferase from the simian virus 40 promoter and from the beta interferon (IFN-β) promoter, while M proteins of interferon-inducing viruses were unable to inhibit luciferase expression from either promoter. The M genes of the interferon-inducing mutants of VSV were incorporated into the wt background of a recombinant VSV infectious cDNA clone. The resulting recombinant viruses were tested for their ability to activate interferon gene expression and for their ability to inhibit host RNA and protein synthesis. Each of the recombinant viruses containing M protein mutations induced expression of a luciferase reporter gene driven by the IFN-β promoter and induced production of interferon bioactivity more effectively than viruses containing wt M proteins. Furthermore, the M protein mutant viruses were defective in their ability to inhibit both host RNA synthesis and host protein synthesis. These data support the idea that wt M protein suppresses interferon gene expression through the general inhibition of host RNA and protein synthesis.
TL;DR: It is argued that the optimization of the FISH protocol to describe the phylogenetic composition of bacterial assemblages will probably lead to techniques that are not effective to describeThe physiological state of cells.
TL;DR: In this article, the authors investigate the factors explaining differential growth in biotechnology firms and add some caution to the generalized opinion according to which alliances are the key factor behind new firm performance.
TL;DR: In this article, the unwanted loss of luminescence in feldspar is given as a function of three variables, the measured fading rate, the laboratory radiation dose rate, and the environmental radiation dose rates.
TL;DR: This study shows for the first time an impaired cortical activation during both wakefulness and REM sleep in idiopathic RBD, despite an absence of changes on sleep architecture compared with controls.
Abstract: Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by a loss of atonia and an increase in phasic muscle activity during REM sleep, leading to complex nocturnal motor behaviors. Brainstem structures responsible for the pathogenesis of RBD are also implicated in cortical activation. To verify the hypothesis that electroencephalogram (EEG) activation will be impaired in RBD, we performed quantitative analyses of waking and REM sleep EEG in 15 idiopathic RBD patients and 15 age- and gender-matched healthy subjects. During wakefulness, RBD patients showed a considerably higher theta power in frontal, temporal, and occipital regions with a lower beta power in the occipital region. The dominant occipital frequency was significantly lower in RBD. During REM sleep, beta power in the occipital region was lower in RBD. This study shows for the first time an impaired cortical activation during both wakefulness and REM sleep in idiopathic RBD, despite an absence of changes on sleep architecture compared with controls. EEG slowing in these patients may represent an early sign of central nervous system dysfunction, perhaps paralleled by subclinical cognitive deficits. The topographical distribution of EEG slowing and possible pathophysiological mechanisms are discussed in light of the known association between RBD and neurodegenerative disorders.
TL;DR: In this paper, a modified value at risk (VaR) and modified Sharpe ratio (MSR) is used to measure risk-adjusted performance of hedge funds. But, the authors found that the modified SR is lower and more accurate when examining non-normal returns.
Abstract: Many institutional investors use the traditional Sharpe ratio today to examine the risk-adjusted performance of funds of hedge funds (FOFs). However, this could pose problems due to the non-normal returns of this alternative asset class. A modified value at risk (VaR) and modified Sharpe ratio solves the problem and can provide a superior tool for correctly measuring risk-adjusted performance. In this article, the authors rank 30 funds of hedge funds according to the Sharpe and modified Sharpe ratio. Their results indicate that the modified Sharpe is lower and more accurate when examining non-normal returns.
TL;DR: Maternal blood Mn levels were negatively associated with foetal plasma HVA and 5-HIAA concentrations, but adjustment for monoamine levels at birth did not change the association between the Mn levels and the psychomotor scores.
Abstract: Several studies have demonstrated neurobehavioral impairment related to manganese (Mn) exposure in the workplace Exposure to high doses of manganese is associated with irreversible neurodegenerative disorders resembling idiopathic Parkinson disease Although there is a risk of Mn accumulation in the foetus during pregnancy, little information exists about developmental effects of environmental low-level exposure in human For this reason, we conducted a prospective epidemiological study in 247 healthy pregnant women and their babies to determine the long-term effect of in utero Mn levels on child's psychomotor development Concurrently, we examined the relationship between Mn tissue levels at delivery and foetal plasma monoamine metabolites Of the newborns, 195 were examined at 9 months, 126 at 3 years and 100 at 6 years At 9 months, the Brunet-Lezine scales were administered The McCarthy scales of children's abilities were used at 3 and 6 years After adjustment for potential confounding co-factors (child's gender, mother's educational level), negative relationships were observed between cord blood Mn levels and several psychomotor sub-scales at age of 3 years: "attention" (partial r=-033, P<0001), "non-verbal memory" (partial r=-028, P<001), and "hand skills" (partial r=-022, P<005) No significant relationships were observed between Mn measures at birth and the general psychomotor indices, Brunet-Lezine developmental quotient (DQ) at 9 months or McCarthy general cognitive index (GCI) at 3 and 6 years Maternal blood Mn levels were negatively associated with foetal plasma HVA and 5-HIAA concentrations (adjusted for labour duration, child's gender, and smoking during pregnancy), but the adjustment for monoamine levels at birth did not change the association between the Mn levels and the psychomotor scores These results suggest that environmental Mn exposure in utero could affect early psychomotor development
TL;DR: Structural equation models showed that both the in-school and the after-school peer networks uniquely contributed to explaining variance in 2 types of individual problem behavior and that similarity with the 2 peer networks varied according to behaviors specific to each context and across gender.
Abstract: Peer relations across 2 contexts (in school and after school) were examined for 577 participants, approximately 12 years old, from 3 middle schools in Milan, Italy. The primary research questions were: Do peer networks from different contexts uniquely contribute to explaining variance in individual behavior? Do measures of peer preference and peer network inclusion across contexts uniquely contribute to explaining individual depressive symptoms? Structural equation models showed that both the in-school and the after-school peer networks uniquely contributed to explaining variance in 2 types of individual problem behavior (in-school problem behavior, after-school delinquency), and that similarity with the 2 peer networks varied according to behaviors specific to each context and across gender. Finally, both in-school and after-school peer network inclusion contributed to explaining variance in depressive symptoms, after controlling for classroom peer preference.
TL;DR: In this paper, a hybrid electrochemical capacitor using MnO 2 and Fe 3 O 4 as active material for the positive and the negative electrode, respectively, has been designed, and the electrodes have been individually tested in a mild aqueous electrolyte (0.1 M K 2 SO 4 ) to define the adequate balance of active material in the capacitor as well as the working voltage of a capacitor based on these two electrodes.
Abstract: A hybrid electrochemical capacitor using MnO 2 and Fe 3 O 4 as active material for the positive and the negative electrode, respectively, has been designed. The electrodes have been individually tested in a mild aqueous electrolyte (0.1 M K 2 SO 4 ) to define the adequate balance of active material in the capacitor as well as the working voltage of a capacitor based on these two electrodes. The specific capacitances of MnO 2 and Fe 3 O 4 were 150 ′ 10 and 75 ′ 8 F/g, respectively whereas the specific capacitance of the Fe 3 O 4 /MnO 2 capacitor was equal to about 20 F/g of active material. The hybrid electrochemical capacitor has been cycled between 0 and 1.8 V for over 5000 constant current charge/discharge cycles. A real energy density of 7 Wh/kg was reproducibly measured with a real power density up to 820 W/kg.
TL;DR: This article investigated the associations between passion for the Internet and level of self-determined motivation toward the couple's relationship and found that an obsessive passion toward the Internet was associated with lower self-determination in the couple, greater conflict in the relationship, and low levels of dyadic adjustment.
Abstract: Based on a motivational perspective of passion, we investigated the associations between passion for the Internet and level of self-determined motivation toward the couple’s relationship. Our results show that an obsessive passion toward the Internet was associated with lower self-determination in the couple, greater conflict in the relationship, and low levels of dyadic adjustment. In contrast, harmonious passion toward the Internet was associated with greater self-determination in the couple, less conflict, and greater dyadic adjustment. Results suggest that use of the Internet is not necessarily associated with ncgative interpersonal outcomes. Rather, it appears that the way the activity has been internalized is associated with how individuals internalize their reasons for behaving in other domains.
TL;DR: Girls appeared to be more precocious in differentiating their competence and intrinsic motivation according to academic domain, as well as in being able to process and integrate information about their ability from past performances in a domain to judge their competence in the same domain.
Abstract: Background: Children's perceived competence and intrinsic motivation are assumed to be very high at the outset of schooling. However, how they change and how they relate to each other and to academic achievement across early schooling years remain open to question.
Aims: This 3-year longitudinal study was aimed at examining the following questions. Do children's perceived competence and intrinsic motivation about reading and mathematics change across the first 3 years of schooling? Do their perceived competence and intrinsic motivation differ according to academic domains? Do their perceived competence and intrinsic motivation relate to their academic achievement in each academic domain?
Sample: A total of 115 elementary schoolchildren (63 boys and 52 girls) were examined in first grade (mean age = 84,5 months, SD = .67) and for the next 2 years.
Method: Children responded to questionnaires about their perceived competence and intrinsic motivation in reading and mathematics. Year-end grades in these two subjects were used as a measure of performance.
Results: Changes in perceived competence and intrinsic motivation, and between-year intercorrelations, were observed to differ according to academic domains and gender. Intrinsic motivation did not make a significant contribution to academic achievement at either school grade or in any academic domain, whereas perceived competence was significantly related to achievement at each school grade in both reading and mathematics.
Conclusions: Differences between boys and girls observed in this study were not linked to a specific domain and cannot be attributed to gender-role stereotypes. Girls appeared to be more precocious in differentiating their competence and intrinsic motivation according to academic domain, as well as in being able to process and integrate information about their ability from past performances in a domain to judge their competence in the same domain.
TL;DR: Findings suggest that children are consistent in the type of aggression they use over time, whether it be indirect or physical, and support the notion that maturation is associated with changes in the ways children aggress.
Abstract: The purpose of the present study was to examine whether indirect aggression was distinct from physical aggression across developmental periods. Participants were 3,089 Canadian children aged 4 to 7 years (Time 1), 6 to 9 years (Time 2), and 8 to 11 years (Time 3). Confirmatory factor analysis using an accelerated longitudinal design confirmed a 2-factor model that was stable across cohorts, time, and sex. The longitudinal predictive links between indirect and physical aggression were also examined in a path analysis. Findings did not support the notion that maturation is associated with changes in the ways children aggress but rather suggest that children are consistent in the type of aggression they use over time, whether it be indirect or physical.
TL;DR: In this paper, two long Holocene piston cores were raised from the St. Lawrence Estuary, eastern Canada because of the expanded Holocene sediment sequence this location provides, supporting a u-channel-based paleomagnetic study, supported by an accelerator mass spectrometry (AMS) 14C chronology, rock-magnetic and sedimentological data.
TL;DR: Goy et al. as discussed by the authors conducted detailed geological mapping, morphostratigraphic, palaeontological and geochronological analyses on the raised marine terraces and interbedded terrestrial deposits along the Spanish peninsular and insular Atlantic and Mediterranean coasts.
01 Jan 2003
TL;DR: A state-of-the-art survey of parallel meta-heuristic developments and results is presented, and general design and implementation principles that apply to most meta- heuristic classes are discussed and instantiate these principles for the three meta-Heuristic classes currently most extensively used.
Abstract: We present a state-of-the-art survey of parallel meta-heuristic developments and results, discuss general design and implementation principles that apply to most meta-heuristic classes, instantiate these principles for the three meta-heuristic classes currently most extensively used—genetic methods, simulated annealing, and tabu search, and identify a number of trends and promising research directions.