Добірка наукової літератури з теми "Indices contextuels"

Cette expérience tente de différencier deux voies de construction des catégories taxonomiques surordonnées selon les domaine (objets naturels vs. fabriqués). La voie perceptive (Quinn, Eimas, 1997) serait privilégiée pour certains objets naturels du fait d’un apprentissage visuel et la voie contextuelle (Nelson, 1982) pour certains objets artificiels, du fait de l’interaction directe avec ces objets. Une étude longitudinale utilisant une épreuve de tri est proposée à des enfants de 3 ans (3 sessions tous les 6 mois). Les enfants peuvent produire des tris soit thématiques, soit taxonomiques. Les associés taxonomiques peuvent être regroupés sur la base 1° d’un contexte commun ou non et 2° de leur ressemblance ou non. Quatre catégories sont étudiées : animaux, aliments, véhicules, jouets. Les indices perceptifs et contextuels semblent utilisés différentiellement, selon les domaines, entre 3 et 5 ans. La prise en compte de l’information contextuelle diminue pour les objets naturels à 4 ans et demi alors que l’information perceptive augmente. En revanche, les deux sortes d’indices perdurent pour les objets artificiels. Ainsi, plusieurs critères de catégorisation coexistent chez le jeune enfant, pondérés différemment selon les individus et les domaines.

Introduction Malgré l'usage répandu d'indices de défavorisation en santé publique, leur validation est rarement abordée de manière explicite ou élaborée, car il s'agit là d'un exercice complexe. Méthodologie En nous fondant sur les propositions de chercheurs britanniques, nous avons cherché à valider l'indice québécois de défavorisation matérielle et sociale en utilisant des critères de validité (validité de contenu, validité sur critère et validité de construit), de fiabilité, de sensibilité et d'autres propriétés pertinentes en santé publique (intelligibilité, objectivité et praticabilité). Résultats Nous avons passé en revue la littérature internationale sur les indices de défavorisation ainsi que les publications et les utilisations de l'indice québécois et nous avons ajouté des données factuelles. Conclusion Après examen, il appert que l'indice québécois répond favorablement aux critères et propriétés de validation proposés. Des validations additionnelles s'imposent toutefois afin de mieux cerner les facteurs contextuels associés à cet indice.

L’autonomie des femmes a été reconnue comme une condition essentielle au développement lors de la Conférence internationale sur la population et le développement de Caire en 1994. Cette étude examine les facteurs contextuels (notamment des normes de genre légitimant la violence envers les femmes) et les facteurs individuels (dont le niveau d’instruction et le type d’emploi) sur l’autonomie décisionnelle des femmes en milieu rural au Ghana, au Kenya, en Ouganda et en Tanzanie. Elle utilise les données issues des enquêtes démographiques et de santé (EDS) de ces pays. La mesure des normes de genre à partir de la perception qu’ont les femmes de la violence domestique (d’un homme sur son épouse) dans leur communauté en recourant à l’analyse factorielle confirmatoire a donné de bons indices d’ajustement qui renforcent la validité de cette méthode. Une augmentation d’un écart-type de cette variable contextuelle est associée à un accroissement des risques pour une femme d’avoir une faible autonomie décisionnelle de 54 % au Ghana, de 45 % au Kenya, de 48 % en Ouganda et de 25 % en Tanzanie. L’instruction et le statut socioéconomique des femmes ne présentent pas la même stabilité sur l’autonomie décisionnelle des femmes. Nos résultats témoignent de la nécessité d’une politique plus globale pour renforcer l’autonomie des femmes en Afrique subsaharienne.

Résumé Cet article tente d’esquisser la contribution des phénomènes segmentaux et suprasegmentaux au décodage perceptif rudimentaire tel qu’il se manifeste chez le débutant en langue seconde. Selon Berkovits (1980), l’apport des habiletés phonétiques se ferait valoir surtout au niveau débutant étant donné que l’apprenant qui n’a aucune connaissance de la langue cible ne peut se prévaloir d’informations sémantiques, pragmatiques ou syntaxiques (Conrad, 1985) disponibles chez l’apprenant avancé ou le locuteur natif. Comme en témoignent les écrits recensés, qu’il s’agisse de la compréhension dans un but communicatif ou en vue du développement de la langue cible en général (au sens de Sharwood-Smith, 1986), il semble que le processus de décodage de compréhension auditive soit lié au développement des habiletés phonétiques dans la mesure où ces dernières contribuent à la segmentation de l’intrant, à l’accès lexical et constituent des indices linguistiques contextuels qui permettent d’accéder à un sens rudimentaire.

In environments where information asymmetries and changing market conditions are ever-present, discerning between different macro-level and contextual factors that stimulate or inhibit entrepreneurial activity still needs to be validated. Utilizing our own primary data ( N = 1473 across 10 countries) as well as secondary data (World Bank Economic Forum, Global Financial Data, and Transparency International), we investigate the role that several contextual indices (e.g. perceptions of an entrepreneurial culture) and macro-level indices (e.g. government corruption, GDP per capita, and ease of doing business indices) have on entrepreneurial intentions. Results reveal the impact government corruption and the concomitant transactional impediments have on the degree of entrepreneurial interest across countries.

Abstract Lexical items that are encountered more frequently and in varying contexts have important effects on second language (L2) development because frequent and contextually diverse words are learned faster and become more entrenched in a learner’s lexicon (Ellis 2002a, b). Despite evidence that L2 learners are generally exposed to non-native input, most frequency and contextual diversity metrics used in L2 research represent what is produced by native speakers of English. This study develops and tests indices of lexical frequency and contextual diversity based on L2 output. The L2 indices were derived from an L2 English learner adult corpus that contained three sub-corpora based on language levels (i.e. low, medium, and high). These indices were used to predict human scores of 480 independent essays from the Test of English as a Foreign Language (TOEFL). First language (L1) indices reported by the Tool for the Automatic Analysis of Lexical Sophistication (TAALES) were also calculated. Three regression analyses were run to predict human scores using L2 indices, L1 indices, and combined indices. The results suggested that the L2 model explained a greater amount of variance in the writing scores and that the L2 model was statistically superior to the L1 model. The findings also suggested that contextual diversity indices are better predictors of writing proficiency than lexical frequency for both the L2 and the L1 models. Finally, an index from the lower level learner sub-corpus was found to be the strongest predictor. The findings have important implications for the analysis of L2 writing in that the L2 benchmarks are more predictive than the L1 benchmarks. These findings could extend human and machine scoring approaches as well as help explain L2 writing quality.

AbstractObjective:Using the African Neuropsychology Battery (ANB), we seek to develop normative data by examining the demographic effects for two learning process scores: initial learning (Trial One) and learning ratio (LR, the percentage of items learned relative of to-be-learned material following Trial 1).Methods:Healthy participants from the Democratic Republic of Congo completed the four memory tests of the ANB: the African Story Memory Test (ASMT), African List Memory Test (ALMT), African Visuospatial Memory Test (AVMT), and African Contextual Visuospatial Memory Test (ACVMT). We developed indices of learning for each subtest, as well as aggregate learning indices for Trial 1 and LR, and composite indices examining verbal, visual, contextual, and noncontextual learning, and grand indices comprising all four subtests.Results:Trial 1 and LR scores each demonstrated acceptable intercorrelations across memory tests. We present normative data for Trial 1 and LR by age and education.Conclusion:These data provide normative standards for evaluating learning in Sub-Saharan Africa.

In the present study, interactions of contextual interference and the cognitive style reflection-impulsivity were examined for training and retention performance. 64 subjects were randomly assigned to either a random or blocked practice schedule in learning a cursor-movement task. Reflectivity indices were determined by means of our computerized version of the Matching Familiar Figures Test. Analysis showed that the generally positive effect of practicing under a random practice schedule decreased for more reflective subjects. Further, training under a random practice schedule forced impulsive subjects to behave more like reflective ones, which improved their performance at retention. It was concluded that reflection-impulsivity is an important factor to be incorporated into the design of effective training programs.

L’exploitation de données radiographiques, en particulier pour la reconstruction 3D du rachis de patients scoliotiques, est un prérequis à la modélisation personnalisée. Les méthodes actuelles, bien qu’assez robustes pour la routine clinique, reposent sur des ajustements manuels fastidieux. Dans ce contexte, ce travail de thèse vise à la détection automatisée de points anatomiques spécifiques des vertèbres, permettant ainsi des ajustements automatisés. Nous avons développé premièrement une méthode originale de localisation de coins de vertèbres cervicales et lombaires sur les radiographies sagittales. L’évaluation rigoureuse de cette méthode suggère sa robustesse et sa précision. Nous avons ensuite développé un algorithme pour le problème pertinent cliniquement de localisation des pédicules sur les radiographies coronales. Cet algorithme se compare favorablement aux méthodes similaires dans la littérature, qui nécessitent une saisie manuelle. Enfin, nous avons soulevé les problèmes, relativement peu étudiés, de détection, identification et segmentation des apophyses épineuses du rachis cervical dans les radiographies sagittales. Toutes les tâches mentionnées ont été réalisées grâce à une combinaison originale de descripteurs visuels et une classification multi-classe par Random Forest, menant à une nouvelle et puissante approche de localisation et de segmentation. Les méthodes proposées dans cette thèse suggèrent un grand potentiel pour être intégré à la reconstruction 3D du rachis, utilisée quotidiennement en routine clinique
Exploitation of spine radiographs, in particular for 3D spine shape reconstruction of scoliotic patients, is a prerequisite for personalized modelling. Current methods, even though robust enough to be used in clinical routine, still rely on tedious manual adjustments. In this context, this PhD thesis aims toward automated detection of specific vertebrae landmarks in spine radiographs, enabling automated adjustments. In the first part, we developed an original Random Forest based framework for vertebrae corner localization that was applied on sagittal radiographs of both cervical and lumbar spine regions. A rigorous evaluation of the method confirms robustness and high accuracy of the proposed method. In the second part, we developed an algorithm for the clinically-important task of pedicle localization in the thoracolumbar region on frontal radiographs. The proposed algorithm compares favourably to similar methods from the literature while relying on less manual supervision. The last part of this PhD tackled the scarcely-studied task of joint detection, identification and segmentation of spinous processes of cervical vertebrae in sagittal radiographs, with again high precision performance. All three algorithmic solutions were designed around a generic framework exploiting dedicated visual feature descriptors and multi-class Random Forest classifiers, proposing a novel solution with computational and manual supervision burdens aiming for translation into clinical use. Overall, the presented frameworks suggest a great potential of being integrated in current spine 3D reconstruction frameworks that are used in daily clinical routine

La maladie d’Alzheimer (MA) est actuellement considérée comme un enjeu majeur de santé publique. Face à la stagnation des résultats issus des approches médicamenteuses, le développement et la validation de stratégies de prise en charge non médicamenteuses sont aujourd’hui particulièrement encouragées. Les odeurs et le regard direct (i.e. un regard dirigé vers soi qui aboutit à une situation de contact par le regard) sont deux indices contextuels connus pour avoir des influences bénéfiques communes sur la cognition normale. L’objectif de ces travaux de thèse est de déterminer si ces influences sont préservées dans le vieillissement normal et dans la MA débutante. Nous nous sommes attachées à déterminer notamment si, dans ces deux populations: i) le regard direct induit une évaluation plus positive d’autrui et améliore la mémoire des visages ainsi que des associations prénoms-visages, ii) les odeurs sont des indices pertinents pour stimuler la mémoire autobiographique, par rapport à d’autres indices sensoriels, iii) un effet cumulatif des odeurs et du regard direct sur l’évaluation d’autrui ainsi que sur la mémoire des visages peut être observé (données de ce dernier axe finalisées uniquement dans la population adulte jeune à ce jour). Nos travaux explorent ces questions à travers quatre études comportementales, dont une intégrant également des données d’oculométrie. Dans leur ensemble, nos résultats indiquent que les effets du regard direct sont préservés dans le vieillissement normale et la MA débutante: la perception d’un regard direct influence positivement l’évaluation d’autrui (étude 1), peut augmenter la mémoire des visages et la mémoire des prénoms (sans toutefois augmenter la mémoire de l’association visage-prénom – étude 2). Par ailleurs, dans ces populations, les stimuli olfactifs et visuels peuvent être considérés des outils de stimulation de la mémoire autobiographique plus pertinents que les stimuli auditifs (étude 3). Enfin, des données préliminaires de nature comportementale suggèrent une prédominance des effets des odeurs sur ceux du regard direct sur le plan de l’évaluation d’autrui chez les sujets jeunes (étude 4). La partie conclusive de cette thèse ouvre une réflexion sur les stratégies d’utilisation de ces indices dans un contexte clinique de stimulation cognitive des patients MA aux premiers stades de la maladie
Alzheimer’s disease (AD) is considered as a major public health concern. Given the poor outcomes associated with pharmacological approaches in dementia care, development and validation of non-pharmacological interventions have been promoted lately. Odors and direct gaze (i.e. another individual’s gaze directed to the observer leading to eye contact) are two contextual cues that are known to influence positively a wide range of cognitive processes in normal cognition. In this work, we aim to determine whether odors and direct gaze effects are preserved in normal ageing and in AD patients at the early stages of the disease. We namely aim to test whether, in these two populations i) direct gaze induces more positive appraisal of others and enhances memory for faces and for face-name association, ii) odors can be considered as particularly relevant cues to stimulate autobiographical memories as compared to other sensory cues, iii) a cumulative effect of odors and direct gaze effects on others’ appraisal and on memory for faces can be observed (data only recorded in healthy young to date). Our work explores these issues through four sets of behavioral studies, one of which also includes eye-tracking recording. Overall, our results suggest that direct gaze effects are preserved in normal ageing and in AD patients: perceiving a direct gaze influences positively others’ appraisal (study 1) and can increase memory for faces and for name (although it does not increase the memory of face-name association – study 2). In addition, we showed that olfactory and visual stimulation can be considered as a more relevant tool for autobiographical memory stimulation than auditory stimulation (study 3). Finally, preliminary behavioral data suggest a predominance of odors’ effects over direct gaze’s ones on others’ appraisal in young subjects (study 4). We discuss our findings in the context of their clinical implications. We namely evoke some cognitive stimulation strategies for AD patients involving direct gaze and odors

La navigation autonome des véhicules dans les zones urbaines implique des interactions avec les différents usagers de la route ou agents de la circulation partageant le même réseau routier comme les voitures, les vélos et les piétons. La capacité du véhicule autonome à observer, comprendre et prédire le comportement de ces agents est très importante pour acquérir une bonne compréhension de la situation avant de décider de la manœuvre à suivre. Bien que cela soit réalisé à divers degrés de succès en utilisant des méthodes basées sur des modèles ou des données, les conducteurs humains restent beaucoup plus efficaces dans cette tâche, déduisant instinctivement différents mouvements d'agent même dans des situations inédites et difficiles. De plus, le contexte joue un rôle très important qui permet à nous les humains de comprendre ce qui est perçu et de faire des prédictions plus fines. La nécessité d'accroître la connaissance de la situation des véhicules autonomes, ainsi que des fonctions d'aide à la conduite liées à la sécurité, stimule notre objectif d'exploiter ces informations contextuelles pour prédire les trajectoires futures des agents observés dans différentes conditions.Au cours des dernières années, l'apprentissage automatique s'est avéré efficace pour résoudre une grande variété de problèmes, en particulier ceux associés à la perception. Cette thèse se concentre donc sur le développement de modèles d'apprentissage automatique pour exploiter des informations contextuelles afin d'observer et d'apprendre les trajectoires de différents agents en interaction. Alors que la plupart des modèles proposés dans le passé reposent sur un seul capteur et des techniques basées sur un modèle, les approches actuelles reposent souvent sur l'utilisation de plusieurs capteurs et traitent leurs sorties à l'aide de différentes méthodes d'apprentissage automatique. L'approche proposée dans cette thèse suit ces tendances en combinant les informations de différents capteurs pour prédire les trajectoires des agents observés à l'aide de l'apprentissage automatique, ainsi qu'en intégrant des informations contextuelles et des interactions dans le processus de prédiction.La thèse construit progressivement une architecture d'apprentissage automatique basée sur une formulation théorique et des expérimentations. Notre approche est basée sur un modèle d'encodeur-décodeur LSTM qui accepte les données de différentes entrées. Des observations de trajectoire à partir de données de nuages de points LiDAR 3D et d'informations sémantiques à partir de masques de carte sont utilisées. Les masques de cartes représentent des zones où les agents peuvent opérer ou non, de manière binaire. Les informations sur l'attention des piétons aux véhicules venant en sens inverse obtenues à partir des images des caméras sont également exploitées pour enrichir le système de prédiction de séquence. L'objectif est d'alimenter le modèle avec des indices contextuels et des informations sémantiques.Les architectures d'apprentissage sont construites à partir de jeux de données acquis à partir des capteurs de perception d'un véhicule. Étant donné qu'ils jouent un rôle important dans la résolution des problèmes d'apprentissage, les jeux de données annotés disponibles pour la navigation autonome ont été examinés en fonction de la disponibilité des données des capteurs et des informations contextuelles. Sur cette base, nos expériences ont permis de valider nos modèles et de construire progressivement leur architecture. Leurs performances sont démontrées à l'aide du célèbre jeu de données NuScenes acquis en milieu urbain. Les performances de l'approche proposée comparées aux approches basées sur des modèles et des données démontrent que l'ajout de multiples informations contextuelles et des interactions d'agents permet une augmentation substantielle des performances
Autonomous vehicle navigation in urban areas involves interactions with the different road-users or traffic-agents like cars, bicycles, and pedestrians, sharing the same road network. The ability of autonomous vehicle to observe, understand and predict the behaviour of these traffic-agents is very important to gain a good situation understanding prior to deciding what manoeuvre to follow. While this is achieved to various degrees of success using model-based or data-driven methods, human drivers remain much more efficient at this task, instinctively inferring different agent motions even in previously unseen and challenging situations. Moreover, context plays a very important role that enables us humans to understand what is being perceived and make finer predictions. The need to increase situational awareness of autonomous vehicles, as well as for safety related driving assistance functions, stimulates our goal to exploit contextual information to predict the future trajectories of the observed traffic-agents in different conditions.Over the past years, machine learning has proven to be efficient at solving a wide variety of problems, particularly those associated to machine perception. This thesis therefore focuses on developing machine learning models to exploit contextual information in order to observe and learn the trajectories of different interacting traffic-agents as perceived from an autonomous vehicle. While most models proposed in the past rely on a single sensor and model-based techniques, the current approaches often rely on the use of multiple sensors and process their outputs using different machine learning methods. The approach proposed in this thesis follows these trends by combining information from different sensors to predict the trajectories of the observed traffic-agents using machine learning, as well as integrating contextual information and interactions into the prediction process.The thesis gradually builds a machine learning architecture based on a theoretical formulation and experimentation. Our approach is based on an LSTM encoder-decoder model that accepts data from different inputs. Trajectory observations from 3D LiDAR point-cloud data and semantic information from map-masks are used. Map masks represent areas where the traffic-agents can operate or not, in a binary manner. The information on pedestrian attention to oncoming vehicles obtained from camera images is also exploited to enrich the sequence prediction system. The goal is to feed the model with context-cues and semantic information to enhance the prediction of the traffic-agent trajectories, by knowing whether or not the agents are aware of the presence of the subject vehicle and including knowledge on areas where they are likely to navigate. Moreover, interactions of the autonomous vehicle with traffic-agents often govern its behaviour as the vehicle navigates. A mechanism to incorporate this information to the machine learning model is also developed as an interaction-aware trajectory prediction system enhanced by context-cues.Machine learning architectures are built using datasets acquired from the perception sensors of a vehicle navigating in the expected workspace. As datasets play an important role in solving machine learning problems, available annotated datasets for autonomous navigation were reviewed according to their availability of sensor data and contextual information. Experiments were performed for our models to learn, and gradually build the resulting architecture. Their performance are demonstrated using the well-known NuScenes dataset acquired in urban settings. The performance of the proposed approach were compared with model and data-driven approaches, demonstrating that the incorporation of multiple contextual information and agent interactions provides a substantial performance increase

Archaeologists have portrayed north-central Venezuela as the seat of the Valencioid 'chiefdom' (a.d. 900-1500) and assumed socio-cultural continuity between the Valencioid culture and the historic Caraca Indians. These assumptions have neither been constructed nor tested on socially meaningful archaeological contexts. My research formulates and tests the cognitive value of the non-ceramic evidence recovered from socially meaningful archaeological contexts on the islands of the Central Coast of Venezuela as sources for understanding the developmental trajectory of the Valencioid polity(ies). The data come from archaeological surveys and excavations on 55 offshore islands and at 47 sites. Through horizontal excavation, off-site control units and statistical control over sample size it is established that the economic purpose for the occupation of a large Valencioid campsite at Dos Mosquises Island (a.d. 1400-1500) was primarily to exploit Conch Shell (Strombus gigas) for food and raw material. Other local resources, such as fishes, lobsters, turtles and birds, were complementary. The conceptual polarity food/artefact, often applied to the archaeofaunal analyses, is replaced by contextual discrimination between food, non-food remains and natural objects, which leads to inferences on social group composition, labour division, specialisation, differential access to food and the exportation of shell raw material outside the islands. The results of the contextual analyses of allochthonous mammal and special purpose artefacts indicate the presence of prominent members of the society (chief, shaman and/or warriors) and the ceremonial character of the core locus at the Dos Mosquises site. It is suggested that the organisation of the insular enterprise is most likely controlled from this core locus. From a macro-regional perspective, the resulting analyses challenge the notion of a 600 yearlong unilinear evolution toward social complexity of the Valencioid polity. The previous view of a straightforward, hegemonic character of this polity is replaced by perspective of recurrent long and short-term changes in the nature and intensity of regional interactions between several polities. These interactions were based on a changing multilateral negotiations of power through trade, co-operativev entures,r esourcee xploitation, intermarriage,c eremonial assistancew, arfare and peace. The purported continuity between the insular Valencioids and the Caraca Indians is not supported by the archaeological data.

Dans cette thèse, nous abordons le contrôle moteur du mouvement du coude à travers deux approches expérimentales : une première étude psychophysique a été effectuée chez les sujets humains, et une seconde implique des enregistrements neurophysiologiques chez le singe. Nous avons recensé plusieurs aspects non résolus jusqu’à présent dans l’apprentissage moteur, particulièrement concernant l’interférence survenant lors de l’adaptation à deux ou plusieurs champs de force anti-corrélés. Nous avons conçu un paradigme où des stimuli de couleur aident les sujets à prédire la nature du champ de force externe actuel avant qu’ils ne l’expérimentent physiquement durant des mouvements d’atteinte. Ces connaissances contextuelles faciliteraient l’adaptation à des champs de forces en diminuant l’interférence. Selon le modèle computationnel de l’apprentissage moteur MOSAIC (MOdular Selection And Identification model for Control), les stimuli de couleur aident les sujets à former « un modèle interne » de chaque champ de forces, à s’en rappeler et à faire la transition entre deux champs de force différents, sans interférence. Dans l’expérience psychophysique, quatre groupes de sujets humains ont exécuté des mouvements de flexion/extension du coude contre deux champs de forces. Chaque force visqueuse était associée à une couleur de l’écran de l’ordinateur et les deux forces étaient anti-corrélées : une force résistante (Vr) a été associée à la couleur rouge de l’écran et l’autre, assistante (Va), à la couleur verte de l’écran. Les deux premiers groupes de sujets étaient des groupes témoins : la couleur de l’écran changeait à chaque bloc de 4 essais, tandis que le champ de force ne changeait pas. Les sujets du groupe témoin Va ne rencontraient que la force assistante Va et les sujets du groupe témoin Vr performaient leurs mouvements uniquement contre une force résistante Vr. Ainsi, dans ces deux groupes témoins, les stimuli de couleur n’étaient pas pertinents pour adapter le mouvement et les sujets ne s’adaptaient qu’à une seule force (Va ou Vr). Dans les deux groupes expérimentaux, cependant, les sujets expérimentaient deux champs de forces différents dans les différents blocs d’essais (4 par bloc), associés à ces couleurs. Dans le premier groupe expérimental (groupe « indice certain », IC), la relation entre le champ de force et le stimulus (couleur de l’écran) était constante. La couleur rouge signalait toujours la force Vr tandis que la force Va était signalée par la couleur verte. L’adaptation aux deux forces anti-corrélées pour le groupe IC s’est avérée significative au cours des 10 jours d’entraînement et leurs mouvements étaient presque aussi bien ajustés que ceux des deux groupes témoins qui n’avaient expérimenté qu’une seule des deux forces. De plus, les sujets du groupe IC ont rapidement démontré des changements adaptatifs prédictifs dans leurs sorties motrices à chaque changement de couleur de l’écran, et ceci même durant leur première journée d’entraînement. Ceci démontre qu’ils pouvaient utiliser les stimuli de couleur afin de se rappeler de la commande motrice adéquate. Dans le deuxième groupe expérimental, la couleur de l’écran changeait régulièrement de vert à rouge à chaque transition de blocs d’essais, mais le changement des champs de forces était randomisé par rapport aux changements de couleur (groupe « indice-incertain », II). Ces sujets ont pris plus de temps à s’adapter aux champs de forces que les 3 autres groupes et ne pouvaient pas utiliser les stimuli de couleurs, qui n’étaient pas fiables puisque non systématiquement reliés aux champs de forces, pour faire des changements prédictifs dans leurs sorties motrices. Toutefois, tous les sujets de ce groupe ont développé une stratégie ingénieuse leur permettant d’émettre une réponse motrice « par défaut » afin de palper ou de sentir le type de la force qu’ils allaient rencontrer dans le premier essai de chaque bloc, à chaque changement de couleur. En effet, ils utilisaient la rétroaction proprioceptive liée à la nature du champ de force afin de prédire la sortie motrice appropriée pour les essais qui suivent, jusqu’au prochain changement de couleur d’écran qui signifiait la possibilité de changement de force. Cette stratégie était efficace puisque la force demeurait la même dans chaque bloc, pendant lequel la couleur de l’écran restait inchangée. Cette étude a démontré que les sujets du groupe II étaient capables d’utiliser les stimuli de couleur pour extraire des informations implicites et explicites nécessaires à la réalisation des mouvements, et qu’ils pouvaient utiliser ces informations pour diminuer l’interférence lors de l’adaptation aux forces anti-corrélées. Les résultats de cette première étude nous ont encouragés à étudier les mécanismes permettant aux sujets de se rappeler d’habiletés motrices multiples jumelées à des stimuli contextuels de couleur. Dans le cadre de notre deuxième étude, nos expériences ont été effectuées au niveau neuronal chez le singe. Notre but était alors d’élucider à quel point les neurones du cortex moteur primaire (M1) peuvent contribuer à la compensation d’un large éventail de différentes forces externes durant un mouvement de flexion/extension du coude. Par cette étude, nous avons testé l’hypothèse liée au modèle MOSAIC, selon laquelle il existe plusieurs modules contrôleurs dans le cervelet qui peuvent prédire chaque contexte et produire un signal de sortie motrice approprié pour un nombre restreint de conditions. Selon ce modèle, les neurones de M1 recevraient des entrées de la part de plusieurs contrôleurs cérébelleux spécialisés et montreraient ensuite une modulation appropriée de la réponse pour une large variété de conditions. Nous avons entraîné deux singes à adapter leurs mouvements de flexion/extension du coude dans le cadre de 5 champs de force différents : un champ nul ne présentant aucune perturbation, deux forces visqueuses anti-corrélées (assistante et résistante) qui dépendaient de la vitesse du mouvement et qui ressemblaient à celles utilisées dans notre étude psychophysique chez l’homme, une force élastique résistante qui dépendait de la position de l’articulation du coude et, finalement, un champ viscoélastique comportant une sommation linéaire de la force élastique et de la force visqueuse. Chaque champ de force était couplé à une couleur d’écran de l’ordinateur, donc nous avions un total de 5 couleurs différentes associées chacune à un champ de force (relation fixe). Les singes étaient bien adaptés aux 5 conditions de champs de forces et utilisaient les stimuli contextuels de couleur pour se rappeler de la sortie motrice appropriée au contexte de forces associé à chaque couleur, prédisant ainsi leur sortie motrice avant de sentir les effets du champ de force. Les enregistrements d’EMG ont permis d’éliminer la possibilité de co-contractions sous-tendant ces adaptations, étant donné que le patron des EMG était approprié pour compenser chaque condition de champ de force. En parallèle, les neurones de M1 ont montré des changements systématiques dans leurs activités, sur le plan unitaire et populationnel, dans chaque condition de champ de force, signalant les changements requis dans la direction, l’amplitude et le décours temporel de la sortie de force musculaire nécessaire pour compenser les 5 conditions de champs de force. Les changements dans le patron de réponse pour chaque champ de force étaient assez cohérents entre les divers neurones de M1, ce qui suggère que la plupart des neurones de M1 contribuent à la compensation de toutes les conditions de champs de force, conformément aux prédictions du modèle MOSAIC. Aussi, cette modulation de l’activité neuronale ne supporte pas l’hypothèse d’une organisation fortement modulaire de M1.
In this thesis, we addressed motor control by two experimental approaches: psychophysical studies in human subjects and neurophysiological recordings in non-human primates. We identified unresolved issues concerning interference in motor learning during adaptation of subjects to two or more anti-correlated force fields. We designed paradigms in which arbitrary color stimuli provided contextual cues that allowed subjects to predict the nature of impending external force fields before encountering them physically during arm movements. This contextual knowledge helped to facilitate adaptation to the force fields by reducing this interference. According to one computational model of motor learning (MOdular Selection And Identification model for Control; MOSAIC), the color context cues made it easier for subjects to build “internal models” of each force field, to recall them and to switch between them with minimal interference. In our first experiment, four groups of human subjects performed elbow flexion/extension movements against two anti-correlated viscous force fields. We combined two different colors for the computer monitor background with two forces: resistive (Vr) and assistive (Va). The first two groups were control subjects. In those subjects, the color of the computer monitor changed at regular intervals but the force field remained constant; Vr was presented to the first group while the second group only experienced Va. As a result, the color cues were irrelevant in the two control groups. All control subjects adapted well to the single experienced force field (Vr or Va). In the two experimental groups, in contrast, the anti-correlated force fields and the monitor colors changed repeatedly between short blocks of trials. In the first experimental group (Reliable-cue subjects), there was a consistent relationship between the force and the stimulus (color of the monitor) - the red colour always signalled the resistive force while the green colour always signalled the assistive force. Adaptation to the two anti-correlated forces for the Reliable-cue group was significant during 10 days of training and almost as good as in the Irrelevant-cue groups who only experienced one of the two force fields. Furthermore, the Reliable-cue subjects quickly demonstrated predictive adaptive changes in their motor output whenever the monitor color changed, even during their first day of training, showing that they could use the reliable color context cues to recall the appropriate motor skills. In contrast, the monitor color also changed regularly between red and green in the second experimental group, but the force fields were not consistently associated with the color cue (Unreliable-cue group). These subjects took longer to adapt to the two force fields than the other three groups, and could not use the unreliable color cue change to make predictive changes to their motor output. Nevertheless, all Unreliable-cue subjects developed an ingenious strategy of making a specific “default” arm movement to probe the type of force field they would encounter in the first trial after the monitor color changed and used the proprioceptive feedback about the nature of the field to make appropriate predictive changes to their motor output for the next few trials, until the monitor color changed again, signifying the possibility of a change in force fields. This strategy was effective since the force remained constant in each short block of trials while the monitor color remained unchanged. This showed that the Unreliable-cue subjects were able to extract implicit and explicit information about the structure of the task from the color stimuli and use that knowledge to reduce interference when adapting to anti-correlated forces. The results of this first study encouraged us to advance our understanding of how subjects can recall multiple motor skills coupled to color context stimuli can be recalled, and how this phenomenon can be reflected by the neuronal activity in monkeys. Our aim was to elucidate how neurons of primary motor cortex (M1) can contribute to adaptive compensation for a wide range of different external forces during single-joint elbow flexion/extension movements. At the same time, we aimed to test the hypothesis evoked in the MOSAIC model, whereby multiple controller modules located in the cerebellum may predict each context and produce appropriate adaptive output signals for a small range of task conditions. Also, according to this hypothesis, M1 neurons may receive inputs from many specialized cerebellar controllers and show appropriate response modulations for a wide range of task conditions. We trained two monkeys to adapt their flexion/extension elbow movements against 5 different force-field conditions: null field without any external force disturbance, two anti-correlated viscous forces (assistive and resistive), which depended on movement speed and resembled that used in the human psychophysical study, a resistive elastic force which depended on elbow-joint position and finally, a visco-elastic field that was the linear sum of the elastic and viscous forces field. Each force field was reliably coupled to 5 different computer monitor background colors. The monkeys properly adapted to the 5 different force-field conditions and used the color context cues to recall the corresponding motor skill for the force field associated with each color, so that they could make predictive changes to their motor output before they physically encountered the force fields. EMG recordings eliminated the possibility that a co-contraction strategy was used by the monkeys to adapt to the force fields, since the EMG patterns were appropriate to compensate for each force-field condition. In parallel, M1 neurons showed systematic changes in their activity at the single-neuron and population level in each force-field condition that could signal the required changes in the direction, magnitude and time course of muscle force output required to compensate for the 5 force-field conditions. The patterns of response changes in each force field were consistent enough across M1 neurons to suggest that most M1 neurons contributed to the compensation for all force field conditions, in line with the predictions of the MOSAIC model. Also, these response changes do not support a strongly modular organization for M1.

This study set out to examine contextual level drivers of HIV among the South African Indian community of Chatsworth. Very little is currently known about HIV/AIDS among South African Indians. It was from this starting point that I set out to research this largely unexplored study topic, to gain insight into and understanding of the non-biological factors that underlie the spread of HIV/AIDS among people in Chatsworth. In-depth interviews, informal discussions and participant observation were carried out among community members, including members who were HIV positive. Findings revealed that poverty, gender power relations and stigma were major social factors contributing to the growth of HIV/AIDS within the South African Indian community of Chatsworth. Poverty places many in vulnerable positions, having to choose between treatment and disability grants to buy food for example, and gender inequalities make women more susceptible to contracting HIV than men. Culture plays a role in placing women in high risk situations. Furthermore stigma, denial and discrimination against people living with HIV/AIDS makes it very difficult for HIV positive people to disclose their status and to live their lives in the community. The importance of understanding the context in which the HIV/AIDS pandemic is occurring and the various cultural factors that play a role in the experience of HIV/AIDS in people?s lives, is argued to be vital to the development of successful strategies to prevent and manage the disease.
Thesis (M.A.)-University of KwaZulu-Natal, Durban, 2010.

Recent research indicates that people from multiracial backgrounds may have more malleable racial identification than those with monoracial backgrounds. For multiracial individuals, context may play an important role in racial self-identification. An Asian/White biracial person, for example, might identify more as Asian when around other Asian people or when speaking an Asian language. Also, over one’s lifetime, multiracial people are more likely to change their racial identification than keep it constant. But how do these fluctuations in racial self-definition affect psychological well-being? This chapter discusses how individual difference variables, namely dialectical self-views, moderate the effect of racial identity fluctuation on psychological well-being. In particular, it discusses how malleable racial identification predicts lower psychological well-being only for those with less dialectical-self views (i.e., little tolerance for change and inconsistency).

AbstractSegregation is often viewed and studied as a macro-level phenomenon, described in terms of aggregate patterns across areas. Empirical analyses of segregation are typically conducted at the macro-level as well, explaining changes and variations in segregation through contextual-level factors such as population size, region, or percent White. However, there is an established body of literature that recognizes segregation as an outcome of micro-level processes of locational attainments and residential mobility that considers the role of household characteristics like income, education, and nativity. This work is fundamentally important for testing the dominant theoretical frameworks employed in segregation research, which largely emphasize that segregation is driven by micro-level characteristics and processes and center the barriers and opportunities in residential mobility. Additionally, the locational attainments approach can be linked with outcomes that are essentially consequences of segregation such as educational disparities, health disparities, and unequal exposure to crime. While both levels of analyses are important, a fundamental link between them has been missing which could explicate how locational attainments directly produce residential segregation patterns. In this final empirical chapter, we draw on Fossett’s (2017) difference-of-means approach to calculating segregation indices to establish a direct quantitative link between predicted outcomes from household-level locational attainment models and overall residential segregation outcomes at the community level. This approach opens up a new toolbox of methods that are popular in inequality studies, including regression standardization and decomposition, which allow us to analyze residential segregation as a stratification outcome. We perform this analysis on 25 metropolitan areas with a focus on White-Black, White-Latino, and White-Asian residential segregation in 2010. We find that White-Black segregation is largely attributable to differences in rates of return on resources relevant for locational attainments, while White-Latino and White-Asian segregation can be explained more by group differences in characteristics and resources such as income and nativity.

AbstractSocioeconomic segregation has become a common phenomenon, both in the Global North and Global South, and highly relates to income inequality. The merging of these two notions affects the geography of residential areas which are based on the socio-occupational composition. This chapter focuses on the Jakarta Metropolitan Area (JMA). Not only is Jakarta the largest metropolitan area in Southeast Asia, it is also one of the most dynamic. Batavia, the colonial capital of the former Dutch East Indies in the first half of the twentieth century, was a small urban area of approximately 150,000 residents. In the second half of the century, Batavia became Jakarta, a megacity of 31 million people and the capital of independent Indonesia was beset with most of the same urban problems experienced in twenty-first-century Southeast Asia, including poverty, income inequality, and socioeconomic segregation. This study aims to identify the correlation among income inequality, socioeconomic segregation, and other institutional and contextual factors which caused residential segregation in JMA. The analysis consists of two stages. First, we examine income inequality measured by the Gini Index as well as the occupational structure based on the International Standard Classification of Occupations (ISCO). Second, we investigate residential segregation by using the Dissimilarity Index as a result of socioeconomic intermixing in residential areas. The data in this study comes from multiple sources including Indonesia’s Central Bureau of Statistics, Indonesia’s National Socio-economic Survey (Susenas), Indonesia’s Economic Census, Jakarta’s Regional Bureau of Statistics, and policies related to the housing system and investment in the JMA. This study also produces maps of socioeconomic segregation patterns from several sources including Jakarta’s Geospatial Information Centre, Jakarta’s Spatial Plan Information System, and the Indonesian Poverty Map by the SMERU Research Institute.

AbstractThis chapter examines the relationship between changes in the scientific paradigm and curriculum after 2000 in Turkey and Singapore as case countries that experienced the transition to social constructivist education. This chapter explores the following questions: Can the traces of paradigm shifts be seen in the curricula? What was the education curriculum like in Turkey and Singapore before 2000? Have any changes occurred in the curricula in Turkey and Singapore after 2000? If any apparent changes have occurred in the curricula, how can they be explained through the relationship with the science-knowledge paradigm shift? After 2000, Singapore and Turkey were observed to have adopted the contextual and subjectivist paradigm, which changes based on idiosyncratic conditions, rather than the objectivist science-knowledge paradigm based on the positivist paradigm. Since 2000, Turkey has started to apply the constructivist paradigm in its education system after trying out various education approaches. Likewise, Singapore started to search for a new paradigm following its independence from England in 1959 and separation from Malesia in 1965. Even though the change in Turkey’s curriculum after the 2000s indicates positivism to be questioned, the realist ontology and objectivist approach to knowledge have apparently not been put behind. In the case of Singapore, the constructivism that had evolved over time emerged in the curriculum, not the relativist and anti-realist constructivism. Singapore’s success compared to Turkey’s is debatable; nevertheless, Singapore’s performance on the Trends in International Mathematics and Science Study (TIMSS) and Program for International Student Assessment (PISA) is noteworthy.

AbstractIndian urban infrastructure is in the middle of a massive build-up. For several decades, Indian cities were caught between the demands of an exploding population and the need to provide infrastructure in terms of health, education, transport, and services to meet the core needs of the citizenry. With increasing prosperity and leveraging the strengths of one of the world’s largest and fast-growing economies, Indian policymakers seek to correct their previous underinvestment in city infrastructure. Smart City Mission, Swachh Bharat Mission, and Atal Mission for Rejuvenation and Urban Transformation are some of the policy vehicles planned for a broad transformation of India’s urban agenda. This chapter highlights some of the policy initiatives focused on meeting the objectives of Smart Cities. These policy initiatives are expected to help address the current service delivery gap from an urban infrastructure standpoint. By incorporating technology, improving digital access, innovations in traffic management, investments in mobility solutions, and ensuring that the heritage of the Indian cities is maintained, India seeks to answer the challenge of urbanization of millions. These policy mechanisms and the lessons from their successes and failures constitute this chapter’s core. Indian urban infrastructure developments are unique globally, primarily because of the varying range of urbanization across the country, the contextual rationale and the evolving aspirations of the policymakers, and the devolution of developmental powers to local bodies. The Indian experience of implementing the Smart Cities objectives would be unique in the world, given the scale of the massive investments and the millions of citizens whose lives are impacted.

The four domains of Contextual Safeguarding (CS) have provided the framework for what we are doing to respond to extra-familial harm (EFH). The evidence in this book indicates that they may not always provide enough of a framework to protect against problematic practice within child protection. In response, the five values of CS provide guidance on how we can do CS. Drawing on bell hooks’s (2001) love ethic, this chapter explores the five values of CS: collaboration, ecological, rights-based, strengths-based and evidence-informed, arguing that CS aims to create societies where children can know love. Drawing on findings from each chapter, it explores the need for love to be shown towards children impacted by EFH and practitioners working to protect them.

The aim of this chapter is to determine the effects of perceived role, career, goal, and performance uncertainty on employee task and contextual performance. The research model was constructed around four independent variables (role, career, goal, and performance uncertainty) and two dependent variables (task and contextual performance). Cronbach alphas for each survey were over 0.85. To determine the validity level of the surveys, confirmatory factor analysis was conducted and found that all surveys are between acceptable limits of goodness of fit index. Two hundred thirty-nine employees responded to the surveys. Principal components analysis (PCA) was used to create indices for uncertainty perception. PCA shows that the employees included in the study generally were in role, goal, career, and performance uncertainty. The results indicate that there is a statistically significant effect of role and goal uncertainty on employee task performance. The other main result is that there is a statistically significant effect of role and performance uncertainty on the employees' contextual performance.

This chapter uses harmonized quantitative regional data on the mediating role of LLL policies in the configuration of individuals living conditions. We focus our attention on four indicators: youth unemployment, tertiary education enrolment, early school leavers and NEET rates. To analyse the determinants of the contextual living conditions we fit persistence models, attempting to explain the status in 2014 with the observed conditions in 2006. We find strong evidence of path dependency. This indicates that the regional contextual living conditions of young adults are overwhelmingly dominated by a combination of the region’s history and developments at the national level. Looking forward, a historically prosperous region in a positive national context is likely to remain so, whilst equally a weak region within a weak national context is likely to remain so. If policy makers are intending to influence the contextual living conditions of young adults, they need to be aware of this inertia. Policies at the national level can be changed and they can be devolved. This could be one way of tackling the inertia, i.e. by providing more policy authority to NUTS-2 regions. Highlighting existing data gaps and improving the availability of territorial information are crucial steps to achieve better targeted policy that isn’t contingent up nation-state-based measures.

Funcționarea biocenozelor acvatice este legată direct de condițiile climatice ale unei anumite ecoregiuni. Schimbările climatice din ultimele decenii au dus la estomparea granițelor dintre anotimpuri. Indiferent de factorii care au determinat modificarea regimului de temperatură al unui ecosistem acvatic (climatici sau tehnogeni), aceasta va avea ca rezultat perturbarea ciclurilor sezoniere naturale de dezvoltare și reproducere a hidrobionților. Lucrarea de față prezintă o analiză a dinamicii sezoniere a principalilor parametri fizico-chimici ai râurilor Nistru și Prut din Republica Moldova pentru perioada anilor 2020-2023. Conform Regulamentului de calitate pentru apele de suprafață, apa din râul Prut în perioada analizată a fost atribuită clasei de calitate II (bună) în baza parametrului CCO-Mn și claselor de calitate II și III (bună – moderat poluată) – în baza parametrului CCO-Cr, cu unele excepții, când apa era clasificată ca poluată și atribuită la clasa IV. Indicele capacității de autoepurare a râului a fost stabilit ca fiind scăzut (ICA< 0,2). Indicele CCO-Mn/CCO-Cr variază în intervalul 0,6-0,1, ceea ce indică prezența unor substanțe organice ușor degradabile (indicator de poluare proaspătă și permanentă) și substanțe greu degradabile în apa Prutului.

The article examines variables that might influence associations between dimensions of perfectionism and current feelings of hopelessness and suicidal ideation in pandemic and post-pandemic in university students. Review of the literature indicates that self-oriented and other-oriented perfectionism are possibly adaptive or maladaptive under certain conditions. Implications for the development of comprehensive, and multidimensional models of the perfectionism-suicide risk link in students and for prevention of perfectionists at risk of suicide are discussed.

The early manifestation of the seasons and seasonal temperature's increasing trend for all seasons require adequate solutions of adaptation to climate change. Knowledge of the spatio-temporal variability of climatic parameters that characterize the seasons, focusing on the last decades - a period of time when climatic variability is even more pronounced compared to previous periods, is of particular interest. Analysis of the density of the seasonal average temperature distribution function indicates a shift to the right for the values, which demonstrates warming trend for all the seasons. The highest accelerated rhythm belongs to winters and summers, and in this context the duration of the seasons and the accumulation of daily temperatures with a certain thermal threshold is also changing.

The present work presents the results of the research of the ichthyofauna of the largest accumulation lakes in the Republic of Moldova (Dubăsari on the Dniester River and CosteștiStânca on the Prut River) under the conditions of climate changes and intensification of anthropogenic pressure. The state of profound change in the ichthyocenosis of the Dubasari reservoir is demonstrated, which is currently dominated by small species (gobius species, bleak, bitterling, blackstriped pipefish), and indicates the urgent need to carry out ameliorating measures of populating the ecosystems with economically valuable species of fish, among which a significant share shall be placed on ichthyophagous species of fish, such as pikeperch, northern pike, catfish, asp. The higher share of oxyphilic and reophilous fish species in the fish catches from the Costești-Stânca accumulation lake reveals a more favourable ecological status of this ecosystem compared to the Dubasari accumulation.

O tempo é um dos aspectos mais relevantes quando modelamos a variabilidade contextual. A perspectiva temporal orienta a modelagem de sistemas sensíveis ao contexto. Apesar da percepção natural e consensual do tempo, a modelagem integrada de suas dimensões para o desenvolvimento de software sensível ao contexto é um tema recente de estudo. O Passado é armazenado em Contextos Históricos, o Presente é modelado através do Gerenciamento de Perfis e o Futuro é antecipado usando a Previsão de Contexto. Este artigo discute a modelagem dessas três dimensões nos sistemas sensíveis ao contexto, indica desafios para cada dimensão e propõe uma arquitetura de sistema para gerenciar a variabilidade contextual em sistemas multitemporais. Acredito que este texto possa ser um artigo seminal para estimular e orientar futuras pesquisas sobre aspectos temporais de ambientes computacionais.

Evidence-based practice is often encouraged in most service delivery settings, yet a substantial body of research indicates that service providers often show resistance or limited adherence to such practices. Resistance to the uptake of evidence-based treatments and programs is well-documented in several fields, including nursing, dentistry, counseling, and other mental health services. This research brief discusses the reasons behind provider resistance, with a contextual focus on mental health service provision in school settings. Recommendations are to attend to resistance in the preplanning proposal stage, during early implementation training stages, and in cases in which insufficient adherence or low fidelity related to resistance leads to implementation failure. Directions for future research include not only attending to resistance but also moving toward client-centered approaches grounded in the evidence base.