994 resultados para Micro-processes


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The drumlin sediments at Chimney Bluffs, New York appear to represent a block-inmatrix style glacial melange. This melange comprises sand stringers, lenses and intraclasts juxtaposed in an apparently massive diamicton. Thin section examination of these glacigenic deposits has revealed microstructures indicative of autokinetic subglacial defonnation which are consistent with a deformable bed origin for the diamicton. These features include banding and. necking of matrix grains, oriented plasma fabrics and the formation of pressure shadows at the long axis ends of elongate clasts. Preservation of primary stratification within the sand intraclasts appears to suggest that these features were pre-existing up-ice deposits that were frozen, entrained, then deposited as part of a defonning till layer beneath an advancing ice sheet. Multi-directional micro-shearing within the sand blocks is thought to reflect the frozen nature of the sand units in such a high strain environment. It is also contended that dewatering of the sediment pile leading to the eventual immobilisation of the defonning till layer was responsible for opening sub-horizontal fissures within the diamicton. These features were subsequently infilled with mass flow poorly sorted sands and silts which were subjected to ductile defonnation during the waning stages of an actively deforming till layer. Microstructures indicative of the dewatering processes in the sand units include patches of fine-grained particles within a coarser-grained matrix and the presence of concentrated zones of translocated clays. However, these units were probably confined within an impermeable diamicton casing that prevented massive pore water influxes from the deforming till layer~ Hence, these microstructures probably reflect localised dewatering of the sand intraclasts. A layered subglacial shear zone model is proposed for the various features exhibited by the drumlin sediments. The complexity of these structures is explained in terms of ii superposing deformation styles in response to changing pore water pressures. Constructional glaciotectonics, as implied by the occurrence of sub-horizontal fissuring, is suggested as the mechanism for the stacking of the sand intraclast units within the diamicton. The usefulness of micromorphology in complimenting the traditional sedimentology of glacigenic deposits is emphasised by the current study. An otherwise massive diamicton was shown to contain microstructures indicative of the very high strain rates expected in a complexly deforming till layer. . It is quite obvious from this investigation that the classification of diamictons needs to be re-examined for evidence of microstructures that could lead to the re-interpretation of diamicton forming processes. RESUME Le pacquet de sediments drumlinaire de Chimney Bluffs, New York, represent un "bloc-en-matrice" genre de melange glaciale. Des structures microscopique comprennent l'evidence pour la defonnation intrinseque attribuee a l'origine lit non resistant du drumlin. PreselVation des structures primaires au coeur des blocs arenaces suggere que ceux sont des depots preexistant qui furent geles, entraines et par la suite sedimentes au milieu d'une couche de debris sous-glaciaires en voie de deformation. Des failles microscopiques a l'interieur des blocs arenaces appuient aussi l'idee d'un bloc cohesif (c'est-a-dire gele) au centre d'un till non resistant. Des implications significatives s'emergent de cette etude pour les conditions sous-glaciaire et les processus de la formation des drumlin.

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Extracellular hyper-osmotic (HYPER) stress increases glucose uptake to defend cell volume, when compared to iso-osmotic (ISO) conditions in skeletal muscle. The purpose of this study was to determine a time course for changes in common signaling proteins involved in glucose uptake during acute hyper-osmotic stress in isolated mammalian skeletal muscle. Rat extensor digitorum longus (EDL) muscles were excised and incubated in a media formulated to mimic ISO (290 ± 10 mmol/kg) or HYPER (400 ± 10 mmol/kg) extracellular condition (Sigma Media-199). Signaling mechanisms were investigated by determining the phosphorylation states of Akt, AMPK, AS160, cPKC and ERK after 30, 45 and 60 minutes of incubation. AS160 was found to be significantly more phosphorylated in HYPER conditions compared to ISO after 30 minutes (p<0.01). It is speculated that AS160 phosphorylation increases glucose transporter 4 (GLUT4) content at the cell surface thereby facilitating an increase in glucose uptake under hyper-osmotic stress.

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This qualitative study addresses the question of how teachers negotiate meaning of new curriculum to better understand how curriculum is transformed from a theoretical construct to a practical one. Through interviews with 5 teachers, their experiences were examined as they negotiated the process of implementing new curriculum. Three theoretical constructs provided the entry point into the study: epistemology, teacher knowledge, and teacher learning. Using inductive analysis, 4 points or attributes of negotiation emerged: reference, growth, autonomy, and reconciliation. These attributes provided a theoretical framework from which a constructivist conceptualization of teacher learning and teacher knowledge could serve to understand the process of how teachers negotiate meaning of curriculum. Studied and theorized in this way, teacher knowledge and teacher learning are seen to be inextricably linked in a relationship that is dynamically changed by forces of stability and instability. Theorizing the negotiation of meaning from a constructivist epistemology also strengthened the assertion that negotiating meaning is a unique structural process, and that knowledge construction is therefore unique to each knower and subject to experience in a particular time and place. The implications for such a theory are, first, that it questions the legitimacy of privatized teacher practice and, second, that it calls for a renewed conceptualization of collegial network and relationship to strengthen the capacity for negotiating meaning of curricular initiatives. Understanding the relationship of curricular theory and negotiating meaning also has implications for curriculum development. In particular, the study highlights the necessity of professional discretion and the generative process of negotiating meaning.

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While there has been a recent shift away from isolated, institutionalized living conditions, persons with Intellectual Disabilities (ID) may still experience restricted access to choice when it comes to making decisions about the basic aspects of their lives. A tension remains between protecting individuals from harm and promoting their right to independence and personal liberties. This tension creates complex questions and ethical concerns for care providers supporting persons with ID. This study explored the ethical decision-making processes of care providers and specifically, how care providers describe the balance of protecting supported individuals from harm while promoting their right to self-determination. Semi-structured interviews were conducted with six care providers employed by a local community agency that supports young and older adults with ID. Data were analysed using thematic analysis and broader themes were developed following phases of open and selective coding. Results indicated that care providers described ethical decision-making processes as frequent, complex, subjective, and uncomfortable. All participants described the importance of promoting independent decision-making among the individuals they support and assisting supported individuals to make informed decisions. Participants also reported work colleagues and supervisors as primary sources of information when resolving ethical concerns. This suggests that complex ethical decision-making processes are being taken seriously by care providers and supervising staff. The results of this study are well-positioned to be applied to the development of a training program for frontline care providing staff supporting individuals in community care settings.

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Adult struggling readers are understudied and most evidence-based remedial approaches target youth. This thesis examined relationships among motivation constructs across typical and struggling adult readers. Age was also investigated as a moderator in these relationships. Participants included 198 adults in adult basic education and 138 undergraduate students. Examining the influence of self-efficacy on reading achievement, moderation analyses indicated there were stronger relationships for typical readers. Furthermore, stronger relationships were found for younger participants when moderated by age. Additional regression analyses identified positive relationships between two measures of intrinsic motivation and reading value. This relationship was replicated for avoidance and value. Though age was not uniformly sampled across ability grouping, age did not account for these effects. Despite difficulties with reading, adults still exhibited motivation to engage with texts with equal to greater levels of reading value. Value and intrinsic motivation may have unique developmental courses associated with longstanding reading challenges.

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Tesis (Maestría en Ciencias de Ingeniería Eléctrica, con especialidad en Electrónica) U.A.N.L.

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Tesis (Maestro en Ciencias de la Administración con Especialidad en Producción y Calidad) UANL, 2000

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Tesis (Maestría en Contaduría Pública con Especialidad en Finanzas) U.A.N.L.

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Tesis (Maestría en Ciencias de la Administración con Especialidad en Relaciones Industriales) UANL, 2011.

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Tesis (Maestría en Psicología con Orientación Laboral y Organizacional) UANL, 2013

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Tesis (Maestría en Ciencias con orientación en Gestión e Innovación del Diseño) UANL, 2014.

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Tesis (Maestría en Economía con orientación en Economía Industrial) UANL, 2014.

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Tesis (Maestría en Ciencias con especialidad en Materiales de Construcción) UANL, 2014.

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Tesis (Maestro en Ciencias con orientación en Materiales de Construcción) UANL, 2014.