Electrocortical responses in reward paradigms and their variation related to personality

This thesis was conducted in order to investigate two issues: (1) how sensitive event related potentials (ERPs), and more specifically the medial frontal negativity and the P3 components, are to the valence and magnitude of reward-related stimuli, and (2) whether individual differences have an effect on the sensitivity of these ERP components to these characteristics. This was investigated using two reward-related paradigms. In the "pure gambling task" participants were asked to choose between two cards, each containing varying dollar amounts (large or small). The outcome of the choice (i.e., win or loss) was revealed after the choice was made. Additionally, participants were shown whether the non-chosen card would have been a win or a loss. In the "simple response task", participants were presented with five cues (large win, large loss, small win, small loss or zero) that labelled the trial as either a potential win, a potential loss or no change. Following the cue, a target appeared on the screen and the participant's task was to press the response key while the target was still visible. A success led to a win (gain in money) or no loss (no change) depending on the cue. Thirty participants completed both tasks; afterwards they filled out a set of questionnaires measuring personality and other individual differences relating to risk-taking behaviour. The results of both tasks showed that ERP components can differentiate between the valence and magnitude of reward-related stimuli, although no single component was uniquely related to either of the characteristics as previous suggested in the literature. Additionally, the context of the stimulus presentation (e.g., the task structure, condition within the task) affected the relationships between the ERP components and stimulus characteristics.

Astringency and other oral sensations : biological sources of individual variation and association with food and beverage behaviour

Orosensory perception strongly influences liking and consumption of foods and beverages. This thesis examines the influence of biological sources of individual variation on the perception of prototypical orosensory stimuli, food liking, self-reported alcohol liking and consumption, and indices of health. Two orosensory indices were examined: propylthiouracil (PROP) responsiveness, a genetically-mediated index of individual variation associated with enhanced responsiveness to orosensory stimuli often expressed as PROP taster status (PTS); and thermal taster status (TTS), a recently reported index of orosensory responsiveness. Taster status in PTS and/or TTS confers greater responsiveness to most orosensory stimuli. Gender, age, ethnicity, and fungiform papillae (FP) density were not associated with orosensory responsiveness to tastants, an astringent, and a flavour. Unlike PROP responsiveness, FP density was not associated with TTS. Both PROP responsiveness and TTS were associated with increased responsiveness to orosensory stimuli, including temperature and astringency. For PROP, this association did not hold when stimuli were presented at cold or warm temperatures, which are ecologically valid since most foods and beverages are not consumed at ambient temperature. Thermal tasters (TTs), who perceive 'phantom' taste sensations with lingual thermal stimulation, were more responsive to stimuli at both temperatures than thermal non-tasters (TnTs). While PTS, TIS, and gender affected self-reported liking and consumption of some alcoholic beverages, gender associated with the greatest number of beverage types and consumption parameters, with males generally liking and consuming alcoholic beverages more than females. Age and gender were the best predictors of alcoholic beverageAiking and consumption. As expected, .. liking of bitter and fatty foods and cream was inversely related to PROP responsiveness. TTS did not associate with body mass index or waist circumference, and contrary to previous studies, neither did PROP responsiveness. Taken together, TnTs' greater liking of cooked fruits and vegetables and high alcohol, and astringent alcoholic beverages than TTs suggests differences between TTS groups may be driven by perceived temperature and texture. Neither an interaction between PTS and TTS nor a TTS effect on PROP responsiveness was observed, suggesting these two indices of individual variation exert their influences on orosensory perception independently.

Annual Variation in Bee Community Structure in the Context of Disturbance (Niagara Region, South-Western Ontario)

This study examined annual variation in phenology, abundance and diversity of a bee community during 2003, 2004, 2006, and 2008 in recovered landscapes at the southern end of St. Catharines, Ontario, Canada. Overall, 8139 individuals were collected from 26 genera and sub-genera and at least 57 species. These individuals belonged to the 5 families found in eastern North America (Andrenidae, Apidae, Colletidae, Halictidae and Megachilidae). The bee community was characterized by three distinct periods of flight activity over the four years studied (early spring, late spring/early summer, and late summer). The number of bees collected in spring was significantly higher than those collected in summer. In 2003 and 2006 abundance was higher, seasons started earlier and lasted longer than in 2004 and 2008, as a result of annual rainfall fluctuations. Differences in abundance for low and high disturbance sites decreased with years. Annual trends of generic richness resembled those detected for species. Likewise, similarity in genus and species composition decreased with time. Abundant and common taxa (13 genera and 18 species) were more persistent than rarer taxa being largely responsible for the annual fluctuations of the overall community. Numerous species were sporadic or newly introduced. The invasive species Anthidium oblongatum was first recorded in Niagara in 2006 and 2008. Previously detected seasonal variation patterns were confirmed. Furthermore, this study contributed to improve our knowledge of temporal dynamics of bee communities. Understanding temporal variation in bee communities is relevant to assessing impacts caused on their habitats by diverse disturbances.

Phonon spectra and temperature variation of thermodynamic properties of fcc metals via Finnis-Sinclair type many body potentials: Sutton-Chen and improved Sutton-Chen models

Volume(density)-independent pair-potentials cannot describe metallic cohesion adequately as the presence of the free electron gas renders the total energy strongly dependent on the electron density. The embedded atom method (EAM) addresses this issue by replacing part of the total energy with an explicitly density-dependent term called the embedding function. Finnis and Sinclair proposed a model where the embedding function is taken to be proportional to the square root of the electron density. Models of this type are known as Finnis-Sinclair many body potentials. In this work we study a particular parametrization of the Finnis-Sinclair type potential, called the "Sutton-Chen" model, and a later version, called the "Quantum Sutton-Chen" model, to study the phonon spectra and the temperature variation thermodynamic properties of fcc metals. Both models give poor results for thermal expansion, which can be traced to rapid softening of transverse phonon frequencies with increasing lattice parameter. We identify the power law decay of the electron density with distance assumed by the model as the main cause of this behaviour and show that an exponentially decaying form of charge density improves the results significantly. Results for Sutton-Chen and our improved version of Sutton-Chen models are compared for four fcc metals: Cu, Ag, Au and Pt. The calculated properties are the phonon spectra, thermal expansion coefficient, isobaric heat capacity, adiabatic and isothermal bulk moduli, atomic root-mean-square displacement and Gr\"{u}neisen parameter. For the sake of comparison we have also considered two other models where the distance-dependence of the charge density is an exponential multiplied by polynomials. None of these models exhibits the instability against thermal expansion (premature melting) as shown by the Sutton-Chen model. We also present results obtained via pure pair potential models, in order to identify advantages and disadvantages of methods used to obtain the parameters of these potentials.

Sermón fúnebre en las solemnes exequias que celebraron en la Santa Iglesia Metropolitana de Valencia su excmo. e illmo. Arzobispo y cabildo con asistencia de la M. I. ciudad y de todo el clero secular y regular en sufragio por el alma de su difunto prelado el excmo. illmo. Señor Don Francisco Fabian y Fuero, el dia 13 de octubre de 1801,

UANL

Primera carta pastoral del Ilustrísimo Señor Dr. Fr. Buenaventuradel Sagrado Corazón de María, Portillo y Tejeda tercer Obispo de Zacatecas, dirigida al V. clero secular y regular a todos los fieles de la diócesis

UANL

Circular dirigida por el Ilmo. Sr. Arzobispo de México al Ilmo. y Ve. Cabildo Metropolitano, al de la insigne Colegiata de Guadalupe, al clero secular y regular y a todos sus diocesanos

UANL

Carta pastoral del Illmo. y Rmo. Sr. D. F. Buenaventura del Sagrado Corazón de María, Portillo y Tejeda, tercer Obispo de Zacatecas dirigido al M.I. y venerable cabildo al clero secular y regular y a todos sus amados diocesanos, convocándolos para la próxima peregrinación que Dios mediante tendrá lugar el día tres del próximo octubre...

UANL

Carta pastoral que el Ilmo. Sr. Dr. D. Francisco de P. Verea Obispo de Linares, dirige al venerable clero secular y regular y a todos los fieles de su Diócesis, con motivo de la enciclica que su santidad el señor Pio IX dirigió al orbe católico, el 19 de Enero del corriente año

UANL

Primera carta pastoral que el Ilmo. Sr. Obispo de Puebla Dr. D. José Perfecto Amézquita y Gutierrez dirige al Ilmo. y V. Sr. Dean y Cabildo de la Sta. I. Catedral al V. Clero Secular y Regular y a los fieles de la diocesis al tomar y regular y a los fieles de la diocesis al tomar posesión de la sede episcopal

UANL

Carta pastoral que el segundo obispo de León, Dr. D. Tomas Barón y Morales dirije a su M. I. Cabildo Venerable clero secular y regular y fieles de su diocesis, con motivo de la carta abolición de la esclavitud...

UANL

Carta pastoral que el segundo Obispo de León Dr. D. Tomás Barón y Morales dirije a su muy ilustre cabildo, venerable clero secular y regular y fieles de su diocesis recomendando al establecimiento de la obra de la propagación de la fé

UANL

Jesús al corazón del sacerdote secular y regular o consideraciones esclesiásticas para cada día del mes que pueden servir para un retiro espiritual de diéz días, con la preparación y acción de gracias para el santo sacrificio de la misa

UANL

Bone mineral density measurement and osteoporosis treatment after a fragility fracture in older adults: regional variation and determinants of use in Quebec

Affiliation: Pierre Dagenais : Hôpital Maisonneuve-Rosemont, Faculté de médecine, Université de Montréal

Les Principes d'UNIDROIT et le Code civil du Québec : variation et mutations

Un résumé en anglais est également disponible.