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Black Online, Doctoral Psychology Graduates' Academic Achievement: A Phenomenological Self-Directed Learning PerspectiveWilliams, Cathy Q. 01 January 2015 (has links)
Guided by the conceptual framework of self-directed learning and culture, this study investigated the effectiveness of Title IV private, for-profit colleges and universities (FPCUs). Little research has examined this topic, which is problematic considering the disproportionate rate of student loan defaults experienced by Black FPCU borrowers. A phenomenological design was used to explore the meaning of academic achievement for Black doctorate recipients who attained a doctorate in psychology through an FPCU. This study specifically examined how Black students experience the completion of doctoral psychology programs at 2 FPCUs and what factors contributed to these students finishing their degrees. A unique-criterion-purposive sample of 7 Black students who completed doctoral psychology programs at FPCUs within the past 5 years was recruited to participate in telephone interviews. Moustakas' data analysis steps were applied to the data. The results indicated that study participants saw an association between attaining their doctorates in psychology and their self-actualization. They shared the experiences of selecting a suitable FPCU, choosing a specialty area, negotiating transfer credits, completing the doctoral coursework phase, and completing the dissertation phase. Their commitment to achieving self-actualization was a salient experience in finishing their degrees. A core aspect of self-actualization was their cultural knowledge, which helped them to overcome challenges and persevere. However, the results uncovered some insufficiencies in the FPCUs' practices. They have implications for positive social change by highlighting how FPCU academic support services might use cultural knowledge and self-actualization strategies to maximize the successful matriculation of Black students.
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Directed differentiation of mouse embryonic stem cells into neocortical output neuronsSadegh, Cameron 10 October 2015 (has links)
During development of the neocortex, many diverse projection neuron subtypes are generated under regulation of cell-extrinsic and cell-intrinsic controls. One broad projection neuron class, corticofugal projection neurons (CFuPN), is the primary output neuron population of the neocortex. CFuPN axons innervate sub-cortical targets including thalamus, striatum, brainstem, and spinal cord.
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Managing Dependencies in Knowledge-Based Systems: A Graph-Based ApproachTapankov, Martin January 2009 (has links)
<p>In knowledge-based engineering, the inference engine plays an important part in the behaviour of the system. A flexible and adaptive execution scheme allows the designer to experiment with different modes of operation and selecting an appropriate one with respect to the initial data set and the execution goal.</p><p>In this project, an extension of an existing research prototype software in the field of knowledge-based engineering will be developed, with the goal of building a reliable and easy to use dependency resolution engine that will replace a less-than-ideal current implementation of the same. A discussion will be included how the knowledge concepts and objects can be represented in an abstract mathematical form, converting at the same time the problem of dependency resolution to a more formally specified one in terms of the data abstraction proposed. Some algorithms and methods that are used to operate on the data set will be discussed from both a theoretical and programming point of view, analysing their complexity, proposing and testing their implementation. Graphical interface controls that can be used to visualize and understand easily the relations in the available knowledge base will be also demonstrated.</p><p>The testing and verification of the resulting software will be presented, comparing its behaviour against reference tools serving similar purposes. Methods for validating the consistency of the knowledge base will also be discussed. Finally, the integration of the newly-developed code within the context of the prototype will be discussed, commenting on the new features and functionality gained.</p>
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Re-Conceptualizing the Organizing Circumstance of LearningSpear Ellinwood, Karen Courtenay January 2011 (has links)
This study explores the web-navigation practices of adult learners in higher education and re-conceptualizes the concept of the organizing circumstance of self-managed learning, originated by Spear and Mocker (1984). The theoretical framework draws on funds of knowledge theory from a cultural historical perspective and elaborates a Vygotskian concepts of learning and development by introducing the notion of the distal object and the zone of distal development. The study employed a mixed methods design with an embedded multiple-case study involving half of the twelve participants using a new technology for self-managed learning called Zonebee. Zonebee recorded participants' web navigation, known as Zonebee Trails, providing quantitative data for analysis. Surveys were administered, namely the Metacognitive Awareness Inventory (Schraw&Dennison, 1994), the Index of Learning Styles Inventory (Soloman&Felder, 1986), a survey of technology use (created for this study) and a set of demographic questions. Eleven of the twelve participants also provided interviews in which they described their self-managed learning practices.Findings contradicted the premise in the literature that the learning environment fortuitously determines the learning experience. Participants primarily relied on the internet and computer to manage their learning and made deliberate choices about which tools to use depending upon the purpose of the constituent process of self-managed learning in which they were engaged (assessing, planning, implementing, monitoring, evaluating or producing). Zonebee Trails evidenced participants' engagement in considerable planning before generating focused queries to locate specific materials. Thus, this study suggests that the organizing circumstance operates, not through happenstance alone, but through the confluence of four factors influencing the direction the learner takes: funds of knowledge for learning; learning demands (proximity of the learning object, proximal or distal), conditions for learning (affordances for and constraints on learning); and motivation or purpose of activity. The re-conceptualized organizing circumstance of learning, then, offers a methodological and theoretical way to redefine context and understand how learners manage their own learning.
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高社交焦慮者在指示遺忘作業之回憶表現--從遺忘觀點探討記憶偏誤 / Memory Bias in Socially Anxious Individuals: A Perspective from Directed Forgetting林肇賢, LIN, CHAO-HSIEN Unknown Date (has links)
本研究主要目的在於運用指示遺忘作業探討高社交焦慮者是否有記憶偏誤現象。高社交焦慮組24人與低社交焦慮組20人參與正式實驗,受試者被要求依據指示記住或忘記三種類型刺激詞(社交威脅、中性、社交正向)。作業結果未發現任何顯著之組間差異,但進一步分析發現,在指示記住項目的回憶上,所有受試者皆回憶出較多的社交正向詞(相對於中性詞以及社交威脅詞),顯示記憶的正向偏誤,然而,在指示忘記項目的回憶上,正向偏誤的現象僅出現在低社交焦慮組,不見於高社交焦慮組。此外,相關分析顯示,高社交焦慮組的FNE量表(Fear of Negative Evaluation Scale)得分與指示記住的社交正向詞回憶量成正相關,與指示忘記的社交威脅詞回憶量成負相關;低社交焦慮組的FNE量表得分與指示記住的社交正向詞回憶量成負相關。這些結果顯示高社交焦慮者可能缺乏正向偏誤的保護機制,較一般人更容易遺忘正向評價訊息,因而更容易受到負面評價的影響,於是他們傾向抑制負向評價訊息的回憶,將注意力投注在非威脅訊息,並努力記住正向評價,換言之,他們透過逃避負面評價的方式來維持良好的自我形象。 / The purpose of the present study was to utilize the directed forgetting task to investigate the memory bias in socially anxious individuals. Performance on a directed forgetting task was assessed in socially anxious (n=24) and nonanxious (n=20) individuals. Participants were presented with three types of words (negative social, neutral, positive social) and were cued to either remember or forget each word as it was presented. There were no between-groups differences on a free recall task for words in both remember and forget conditions. Follow-up analyses demonstrated that all subjects recalled more positive social words than either neutral words or negative social words in the remember condition, revealing the positive memory bias. However, only nonanxious individuals showed such positive memory bias in the forget condition, while high-social-anxiety individuals did not. Moreover, in the social anxiety group, the Fear of Negative Evaluation Scale (FNE) scores were positively related to the recall of positive social “to-be-remembered” words, and negatively related to the recall of negative social “to-be-forgotten” words. In the control group, FNE scores were negatively related to the recall of positive social “to-be-remembered” words. These results suggest that the protective positive bias was absent in socially anxious individuals. Thus, they were more likely than nonanxious individuals to forget positive evaluative information; therefore, they were vulnerable to negative evaluation. Furthermore, people with excessive social anxiety might try hard to inhibit the recall of negative evaluation and to remember positive evaluation. In other words, they made an effort to maintain a good impression by avoiding negative evaluative information.
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A theoretical model for the effectiveness of project-based learning in engineering design educationGao, Mingyi January 2012 (has links)
The main focus of this thesis is on the effectiveness of project-based learning (PBL) in engineering design. The literature review has shown that there is much confusion and ongoing arguments concerning the implementation of PBL in engineering design, and there lacks consensus on its effectiveness. Little research has been done on providing measurable metrics of PBL effectiveness, not to mention discovering the optimal PBL and its underlying mechanisms based on solid educational theories and rigorous research methodology. In this thesis, the measurement of the optimal PBL effectiveness (effect) is studied and a theoretical model of PBL is built in order to identify parameters (cause) controlling the effectiveness and to study the interplay between effectiveness and the parameters. The model is built through three main phases, with a combination of qualitative and quantitative research methods. In phase one, the effectiveness of PBL is studied from the perspectives of the engineering design lecturers and engineering graduates by interviews, which is used to represent effect (Y axis) of the model. In phase two, on the basis of self-directed learning theory (SDL) and learner engagement theory,two key parameters of PBL, i.e. SDL and learner engagement, are identified and quantified respectively to represent cause (X axis) of the model. With the key parameters of PBL (X axis) and PBL effectiveness (Y axis) obtained, a theoretical model of PBL is proposed. The model is verified by means of experiments (student self-reported surveys). A specified Moving Average Method (MAM) is used for data analysis and findings demonstrate different trends of the relations between SDL and PBL effectiveness, and between learner engagement and PBL effectiveness. Consequently, a 3D model of PBL is built by combining the data in aforementioned 2D models,through which the optimal PBL effectiveness in 3D are identified and measured and the interplay between different parameters are found. In phase three, in order to find out more delicate features in PBL ignored by MAM, the dynamic interaction of individual differences in PBL teamwork is explored by the ethnological method (including participant observations and interviews), which is conducted as a supplement to the model of PBL. The theoretical model of PBL effectiveness proposed in this thesis is novel and groundbreaking. Firstly, a series of 2D and 3D models are presented and the relations between SDL, learner engagement and PBL effectiveness are revealed for the first time, which provides guidance for the optimal PBL measurement and implementation. Secondly, a qualitatively-quantitatively-combined strategy is used to discover the mechanisms controlling optimal PBL at different scales. Thirdly, the experiments verifying the model provide fresh quantitative insight into optimal PBL. In summary, the research in this thesis opens up a new research methodology for studying PBL effectiveness, which makes contribution to the educational field as well. Keywords: Project-based learning, Self-directed learning, Learner engagement, Optimal PBL effectiveness, 3D model, Individual differences, Engineering design, Pedagogy.
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Exploring the facilitating effect of diminutives on the acquisition of Serbian noun morphologySeva, Nada January 2006 (has links)
Studies of Russian, Polish, and Lithuanian language learners converge on the finding that morphological features of nouns are first generalized to word clusters of high morpho-phonological similarities such as diminutives, that grammatical categorisation is are more easily applied to novel words that fall into these clusters. The present thesis explores whether the facilitating effect of diminutives on the acquisition of complex noun morphology can be extended to Serbian, a south Slavic language, morphologically similar to Russian and Polish. Specifically, the thesis explores the role of parameters responsible for the obtained diminutive advantage: high frequency of a particular cluster of words in child-directed speech (CDS) and morpho-phonological homogeneity within this cluster. A corpus analysis of the distribution of diminutives in Serbian CDS indicated a rather unexpected difference in frequency relative to Russian and Polish CDS, despite the high similarity of the diminutive derivation across these three Slavic languages. Out of the total number of nouns in Serbian CDS only 7% were diminutives, compared to 20-30% in Polish and 45% in Russian. Two experimental studies explored whether the low frequency of diminutives in Serbian CDS attenuates the diminutive advantage in morphology learning compared to Russian and Polish. In the first two experiments, Serbian children exhibited a strong diminutive advantage for both gender agreement and case marking in the same range as Russian children, indicating that morpho-phonological homogeneity within the cluster of diminutives may play as important a role as their frequency for grammatical categorisation of novel nouns. A third study investigated in more detail the effects of morpho-phonological homogeneity on the emergence of the diminutive advantage using a gender-agreement task with novel nouns in simplex and pseudo-diminutive form over four sessions with Serbian children. The results showed a pseudo-diminutive advantage for gender agreement by Session 2, suggesting that the categorisation of nouns into grammatical categories is based on morpho-phonological homogeneity of the word cluster, emerges relatively fast, and can occur despite the much lower frequency of diminutives in Serbian CDS. Finally, a series of neural network simulations designed to capture the pattern of results from the third experimental study was used to examine to what extent a simple associative learning mechanism, relying on morpho-phonological similarity of the noun endings, can explain the findings. The performance of three models, a whole-word feed-forward network, a Simple Recurrent Network (SRN) and a last-syllable feed-forward network, was compared to the experimental data. The superior fit of the SRN suggests that gender learning is based on a very fast sequential build-up of representations of the entire word, allowing the system to exploit the predictive power of word stems to anticipate regularised endings. Overall, the findings of this thesis contribute to our general understanding of mechanisms responsible for the acquisition of complex inflectional noun morphology in two ways. First, by extending experimental studies and neural network simulations to Serbian, the results underline the universality of the idea that noun morphology is learned and processed through a single-route associative mechanism based on the frequency and morpho-phonological structure of nouns. More specifically, the results from experimental studies and neural network simulations demonstrate that for diminutives, the low-level grammatical categorisation is based mainly on the morpho-phonological similarity of word endings, and can emerge after just a few exposures. And second, the neural network simulations suggest that during the process of categorisation of nouns into gender categories, learners rely not only on predictable information from the noun endings, but also on phonological regularities in the stems of nouns. Taken together, these findings contribute also to a better understanding of the facilitating role of CDS in morphology acquisition.
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Directed intervention crossover approaches in genetic algorithms with application to optimal control problemsGodley, Paul Michael January 2009 (has links)
Genetic Algorithms (GAs) are a search heuristic modeled on the processes of evolution. They have been used to solve optimisation problems in a wide variety of fields. When applied to the optimisation of intervention schedules for optimal control problems, such as cancer chemotherapy treatment scheduling, GAs have been shown to require more fitness function evaluations than other search heuristics to find fit solutions. This thesis presents extensions to the GA crossover process, termed directed intervention crossover techniques, that greatly reduce the number of fitness function evaluations required to find fit solutions, thus increasing the effectiveness of GAs for problems of this type. The directed intervention crossover techniques use intervention scheduling information from parent solutions to direct the offspring produced in the GA crossover process towards more promising areas of a search space. By counting the number of interventions present in parents and adjusting the number of interventions for offspring schedules around it, this allows for highly fit solutions to be found in less fitness function evaluations. The validity of these novel approaches are illustrated through comparison with conventional GA crossover approaches for optimisation of intervention schedules of bio-control application in mushroom farming and cancer chemotherapy treatment. These involve optimally scheduling the application of a bio-control agent to combat pests in mushroom farming and optimising the timing and dosage strength of cancer chemotherapy treatments to maximise their effectiveness. This work demonstrates that significant advantages are gained in terms of both fitness function evaluations required and fitness scores found using the proposed approaches when compared with traditional GA crossover approaches for the production of optimal control schedules.
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Levels of resourcefulness and motivation as they relate to sales force success: An examination of correlates using the hope theory.Pool, Patricia W. 12 1900 (has links)
This study sought to determine whether a relationship existed between individual salesperson's levels of goal-directed cognition and motivation and their professional success as determined by the percentage of sales goals achieved. Salespersons represented two companies with national sales forces: one from the financial services industry and one from the apparel manufacturing industry. Both groups of salespeople were responsible for complex selling tasks. The skill sets for these professionals included high levels of communication skills, extensive product knowledge, and competitive market knowledge. Survey research, both paper and pencil and online, was conducted using the Hope Scale developed by C. R. Snyder and associates (1991). Hope is defined as a two-dimensional construct of goal-directed thinking: resourcefulness, thoughtful planning to overcome obstacles to goals, and motivation, cognition to sustain momentum toward goal achievement. Theoretically, upon assessing salespersons' Hope scores, organizations would be better prepared to assist those with low Hope Scale Scores (HSS) in one of the two areas. Those with low resourcefulness scores could be trained in cognitive techniques to overcome obstacles to goal achievement. Those with low motivational scores would be identified for further analysis, from a developmental perspective, to better determine what personally initiates and sustains motivation to attain their goals (Snyder, 1991). This study affirmed two of three parts of the hope theory with regard to salespeople. High Hope scores showed significant correlations with high goal achievement, as did one of the subset scores, motivation. The resourcefulness subset score did not correlate significantly with high goal achievement, and also produced low reliability scores.
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The Argonaute-binding platform of NRPE1 evolves through modulation of intrinsically disordered repeatsTrujillo, Joshua T., Beilstein, Mark A., Mosher, Rebecca A. 12 1900 (has links)
• Argonaute proteins are important effectors in RNA silencing pathways, but they must interact with other machinery to trigger silencing. Ago hooks have emerged as a conserved motif responsible for interaction with Argonaute proteins, but little is know about the sequence surrounding Ago hooks that must restrict or enable interaction with specific Argonautes.
• Here we investigated the evolutionary dynamics of an Argonaute-binding platform in NRPE1, the largest subunit of RNA Polymerase V. We compared NRPE1 sequences from more than 50 species, including dense sampling of two plant lineages.
• This study demonstrates that the Argonaute-binding platform of NRPE1 retains Ago-hooks, intrinsic disorder, and repetitive character while being highly labile at the sequence level. We reveal that loss of sequence conservation is due to relaxed selection and frequent expansions and contractions of tandem repeat arrays. These factors allow a complete restructuring of the Ago-binding platform over 50-60 million years. This evolutionary pattern is also detected in a second Ago-binding platform, suggesting it is a general mechanism.
• The presence of labile repeat arrays in all analyzed NRPE1 Ago-binding platforms indicates that selection maintains repetitive character, potentially to retain the ability to rapidly restructure the Ago-binding platform.
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