14 resultados para Treatment and control
em Digital Commons at Florida International University
The development, application, and implications of a strategy for reflective learning from experience
Resumo:
The problem on which this study focused was individuals' reduced capacity to respond to change and to engage in innovative learning when their reflective learning skills are limited. In this study, the preceding problem was addressed by two primary questions: To what degree can mastery of a strategy for reflective learning be facilitated as a part of an academic curriculum for professional practitioners? What impact will mastery of this strategy have on the learning style and adaptive flexibility of adult learners? The focus of the study was a direct application of human resource development technology in the professional preparation of teachers. The background of the problem in light of changing global paradigms and educational action orientations was outlined and a review of the literature was provided. Roots of thought for two key concepts (i.e., learning to learn from experience and meaningful reflection in learning) were traced. Reflective perspectives from the work of eight researchers were compared. A meta-model of learning from experience drawn from the literature served as a conceptual framework for the study. A strategy for reflective learning developed from this meta-model was taught to 109 teachers-in-training at Florida International University in Miami, Florida. Kolb's Adaptive Style Inventory and Learning Style Inventory were administered to the treatment group and to two control groups taught by the same professor. Three research questions and fourteen hypotheses guided data analysis. Qualitative review of 1565 personal documents generated by the treatment group indicated that 77 students demonstrated "double-loop" learning, going beyond previously established limits to perception, understanding, or action. The mean score for depth of reflection indicated "single-loop" learning with "reflection-in-action" present. The change in the mean score for depth of reflection from the beginning to end of the study was statistically significant (p $<$.05). On quantitative measures of adaptive flexibility and learning style, with two exceptions, there were no significant differences noted between treatment and control groups on pre-test to post-test differences and on post-test mean scores adjusted for pre-test responses and demographic variables. Conclusions were drawn regarding treatment, instrumentation, and application of the strategy and the meta-model. Implications of the strategy and the meta-model for research, for education, for human resource development, for professional practice, and for personal growth were suggested. Qualitative training materials and Kolb's instruments were provided in the appendices.
Resumo:
Historically, memory has been evaluated by examining how much is remembered, however a more recent conception of memory focuses on the accuracy of memories. When using this accuracy-oriented conception of memory, unlike with the quantity-oriented approach, memory does not always deteriorate over time. A possible explanation for this seemingly surprising finding lies in the metacognitive processes of monitoring and control. Use of these processes allows people to withhold responses of which they are unsure, or to adjust the precision of responses to a level that is broad enough to be correct. The ability to accurately report memories has implications for investigators who interview witnesses to crimes, and those who evaluate witness testimony. ^ This research examined the amount of information provided, accuracy, and precision of responses provided during immediate and delayed interviews about a videotaped mock crime. The interview format was manipulated such that a single free narrative response was elicited, or a series of either yes/no or cued questions were asked. Instructions provided by the interviewer indicated to the participants that they should either stress being informative, or being accurate. The interviews were then transcribed and scored. ^ Results indicate that accuracy rates remained stable and high after a one week delay. Compared to those interviewed immediately, after a delay participants provided less information and responses that were less precise. Participants in the free narrative condition were the most accurate. Participants in the cued questions condition provided the most precise responses. Participants in the yes/no questions condition were most likely to say “I don’t know”. The results indicate that people are able to monitor their memories and modify their reports to maintain high accuracy. When control over precision was not possible, such as in the yes/no condition, people said “I don’t know” to maintain accuracy. However when withholding responses and adjusting precision were both possible, people utilized both methods. It seems that concerns that memories reported after a long retention interval might be inaccurate are unfounded. ^
Resumo:
It is projected that by 2020, there will be 138 million Americans over 45, the age at which the increased incidence of heart diseases is documented. Many will require stents. This multi-billion dollar industry, with over 2 million patients worldwide, 15% of whom use Nitinol stents have experienced a decline in sales recently, due in part to thrombosis. It is a sudden blood clot that forms inside stents. As a result, the Food and Drug Administration and American Heart Association are calling for a new generation of stents, new designs and different alloys that are more adaptable to the arteries. The future of Nitinol therefore depends on a better understanding of the mechanisms by which Nitinol surfaces can be rendered stable and inert. In this investigation, binary and ternary Nitinol alloys were prepared and subjected to various surface treatments such as electropolishing (EP), magnetoelectropolishing (MEP) and water boiling & passivation (W&P). In vitro corrosion tests were conducted on Nitinol alloys in accordance with ASTM F 2129-08. The metal ions released into the electrolyte during corrosion tests were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). Biocompatibility was assessed by observing the growth of human umbilical vein endothelial cells (HUVEC) on the surface of Nitinol alloys. Static and dynamic immersion tests were performed by immersing the Nitinol alloys in cell culture media and measuring the amount of metal ions released in solution. Sulforhodamine B (SRB) assays were performed to elucidate the effect of metal ions on the growth of HUVEC cells. The surfaces of the alloys were studied using Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS) respectively. Finally, wettability and surface energy were measured by Contact Angle Meter, whereas surface roughness was measured by Atomic Force Microscopy (AFM). All the surface treated alloys exhibited high resistance to corrosion when compared with untreated alloys. SRB assays revealed that Ni and Cu ions exhibited greater toxicity than Cr, Ta and Ti ions on HUVEC cells. EP and MEP alloys possessed relatively smooth surfaces and some were composed of nickel oxides instead of elemental nickel as determined by XPS. MEP exhibited lowest surface energy and lowest surface roughness.
Resumo:
The purpose of this research was to explore the differences in factors associated with girls' status and criminal arrests. This study used data from six juvenile justice programs in multiple states, which was derived from the Juvenile Assessment and Intervention System (JAIS). The sample of 908 adolescent girls (ages 13-19) was ethnically and racially diverse (41% African American, 32% white, 12% Hispanic, 11% Native American and 4% Other). A structural equation model (SEM) was analyzed which tested the potential effects of adolescent substance use, truancy, suicidal ideation/attempt, self-harm, peer legal trouble, parental criminal history and parental and non-parental abuse on type of offense (status and criminal) and whether any of these relationships varied as a function of race/ethnicity. ^ Complex relationships emerged regarding both status and more serious criminal arrests. One of the most important findings was that distinct and different patterns of factors were associated with status arrests compared to criminal arrests. For example, truancy and parental abuse were directly associated with status offenses, whereas parental criminal history was directly related to criminal arrests. However, both status and criminal arrests shared common associations, including substance use, which signifies that certain variables are influential regarding both non-criminal and more serious crimes. In addition, significant meditating influences were observed which help to explain some underlying mechanisms involved in girls' arrest patterns. Finally, race/ethnicity moderated a key relationship, which has serious implications for treatment. ^ In conclusion, the present study is an important contribution to research regarding girls' delinquency in that it overcomes limitations in the existing literature in four primary areas: (1) it utilizes a large, multi-state, ethnically and racially diverse sample of justice system-involved girls, (2) it examines numerous co-occurring factors influencing delinquency from multiple domains (family, school, peers, etc.) simultaneously, (3) it formally examines race/ethnicity as a moderator of these multivariate relationships, and (4) it looks at status and criminal arrests independently in order to highlight possible differences in the patterning of risk factors associated with each. These findings have important implications for prevention, treatment and interventions with girls involved in the juvenile justice system.^
Resumo:
Higher education institutions across the United States have developed global learning initiatives to support student achievement of global awareness and global perspective, but assessment options for these outcomes are extremely limited. A review of research for a global learning initiative at a large, Hispanic-serving, urban, public, research university in South Florida found a lack of instruments designed to measure global awareness and global perspective in the context of an authentic performance assessment. This quasi-experimental study explored the development of two rubrics for the global learning initiative and the extent to which evidence supported the rubrics' validity and reliability. One holistic rubric was developed to measure students' global awareness and the second to measure their global perspective. The study utilized a pretest/posttest nonequivalent group design. Multiple linear regression was used to ascertain the rubrics' ability to discern and compare average learning gains of undergraduate students enrolled in two global learning courses and students enrolled in two non-global learning courses. Parallel pretest/posttest forms of the performance task required students to respond to two open-ended questions, aligned with the learning outcomes, concerning a complex case narrative. Trained faculty raters read responses and used the rubrics to measure students' global awareness and perspective. Reliability was tested by calculating the rates of agreement among raters. Evidence supported the finding that the global awareness and global perspective rubrics yielded scores that were highly reliable measures of students' development of these learning outcomes. Chi-square tests of frequency found significant rates of inter-rater agreement exceeding the study's .80 minimum requirement. Evidence also supported the finding that the rubrics yielded scores that were valid measures of students' global awareness and global perspective. Regression analyses found little evidence of main effects; however, post hoc analyses revealed a significant interaction between global awareness pretest scores and the treatment, the global learning course. Significant interaction was also found between global perspective pretest scores and the treatment. These crossover interactions supported the finding that the global awareness and global perspective rubrics could be used to detect learning differences between the treatment and control groups as well as differences within the treatment group.
Resumo:
A number of factors influence the information processing needs of organizations, particularly with respect to the coordination and control mechanisms within a hotel. The authors use a theoretical framework to illustrate alternative mechanisms that can be used to coordinate and control hotel operations.
Resumo:
The eggs of the dengue fever vector Aedes aegypti possess the ability to undergo an extended quiescence period hosting a fully developed first instar larvae within its chorion. As a result of this life history stage, pharate larvae can withstand months of dormancy inside the egg where they depend on stored reserves of maternal origin. This adaptation known as pharate first instar quiescence, allows A. aegypti to cope with fluctuations in water availability. An examination of this fundamental adaptation has shown that there are trade-offs associated with it. ^ Aedes aegypti mosquitoes are frequently associated with urban habitats that may contain metal pollution. My research has demonstrated that the duration of this quiescence and the extent of nutritional depletion associated with it affects the physiology and survival of larvae that hatch in a suboptimal habitat; nutrient reserves decrease during pharate first instar quiescence and alter subsequent larval and adult fitness. The duration of quiescence compromises metal tolerance physiology and is coupled to a decrease in metallothionein mRNA levels. My findings also indicate that even low levels of environmentally relevant larval metal stress alter the parameters that determine vector capacity. ^ My research has also demonstrated that extended pharate first instar quiescence can elicit a plastic response resulting in an adult phenotype distinct from adults reared from short quiescence eggs. Extended pharate first instar quiescence affects the performance and reproductive fitness of the adult female mosquito as well as the nutritional status of its progeny via maternal effects in an adaptive manner, i.e., anticipatory phenotypic plasticity results as a consequence of the duration of pharate first instar quiescence and alternative phenotypes may exist for this mosquito with quiescence serving as a cue possibly signaling the environmental conditions that follow a dry period. M findings may explain, in part, A. aegypti's success as a vector and its geographic distribution and have implications for its vector capacity and control.^
Resumo:
High-stakes testing and accountability have infiltrated the education system in the United States; the top priority for all teachers must be student progress on standardized tests. This has resulted in the predominance of reading for test-taking, (efferent reading), in the English, language arts, and reading classrooms. Authentic uses of print activities, like aesthetic reading, that encourage students to engage individually with a text, have been pushed aside. ^ During a 3-week time period, regular level, English 3/American literature students in a Title I magnet high school, participated in this quasi-experimental study (N = 62). It measured the effects of an intervention of reading American literature texts aesthetically and writing aesthetically-evoked reader responses on students' self-efficacy beliefs regarding their comprehension of American literature. One trained teacher and the researcher participated in the study: student participants were pre- and post- tested using the Confidence in Reading American Literature Survey which examined their self-efficacy beliefs regarding their comprehension of American literature. Several statistical analyses were performed. The results of the linear regression analyses partially supported a positive relationship between aesthetically-evoked reader responses and students' self-efficacy beliefs regarding their comprehension of American literature. Additionally, the results of the 2 (sex) x 2 (treatment) ANCOVAs conducted to test group differences in self-efficacy beliefs regarding the comprehension of American literature between treatment and control groups indicated a main effect for treatment (but not sex; nor was there a significant sex x treatment interaction), suggesting the treatment was partially effective in increasing students' self-efficacy beliefs. Seven of the twelve ANCOVAs indicated a statistically significant increase in the treatment group's adjusted group mean self-efficacy belief scores as a result of being exposed to the intervention. In six of these seven analyses, increases in self-efficacy beliefs occurred in tasks that required three or more higher-order levels of thinking/learning. The results are discussed in terms of theoretical, empirical and practical significance. Future research is recommended to extend the intervention beyond the narrow confines of a Title I magnet school to settings where the intervention could be tested longitudinally, e. g., honors and gifted students, elementary and middle schools.^
Resumo:
Virtual machines (VMs) are powerful platforms for building agile datacenters and emerging cloud systems. However, resource management for a VM-based system is still a challenging task. First, the complexity of application workloads as well as the interference among competing workloads makes it difficult to understand their VMs’ resource demands for meeting their Quality of Service (QoS) targets; Second, the dynamics in the applications and system makes it also difficult to maintain the desired QoS target while the environment changes; Third, the transparency of virtualization presents a hurdle for guest-layer application and host-layer VM scheduler to cooperate and improve application QoS and system efficiency. This dissertation proposes to address the above challenges through fuzzy modeling and control theory based VM resource management. First, a fuzzy-logic-based nonlinear modeling approach is proposed to accurately capture a VM’s complex demands of multiple types of resources automatically online based on the observed workload and resource usages. Second, to enable fast adaption for resource management, the fuzzy modeling approach is integrated with a predictive-control-based controller to form a new Fuzzy Modeling Predictive Control (FMPC) approach which can quickly track the applications’ QoS targets and optimize the resource allocations under dynamic changes in the system. Finally, to address the limitations of black-box-based resource management solutions, a cross-layer optimization approach is proposed to enable cooperation between a VM’s host and guest layers and further improve the application QoS and resource usage efficiency. The above proposed approaches are prototyped and evaluated on a Xen-based virtualized system and evaluated with representative benchmarks including TPC-H, RUBiS, and TerraFly. The results demonstrate that the fuzzy-modeling-based approach improves the accuracy in resource prediction by up to 31.4% compared to conventional regression approaches. The FMPC approach substantially outperforms the traditional linear-model-based predictive control approach in meeting application QoS targets for an oversubscribed system. It is able to manage dynamic VM resource allocations and migrations for over 100 concurrent VMs across multiple hosts with good efficiency. Finally, the cross-layer optimization approach further improves the performance of a virtualized application by up to 40% when the resources are contended by dynamic workloads.
Resumo:
It is projected that by 2020, there will be 138 million Americans over 45, the age at which the increased incidence of heart diseases is documented. Many will require stents. This multi-billion dollar industry, with over 2 million patients worldwide, 15% of whom use Nitinol stents have experienced a decline in sales recently, due in part to thrombosis. It is a sudden blood clot that forms inside stents. As a result, the Food and Drug Administration and American Heart Association are calling for a new generation of stents, new designs and different alloys that are more adaptable to the arteries. The future of Nitinol therefore depends on a better understanding of the mechanisms by which Nitinol surfaces can be rendered stable and inert. In this investigation, binary and ternary Nitinol alloys were prepared and subjected to various surface treatments such as electropolishing (EP), magnetoelectropolishing (MEP) and water boiling & passivation (W&P). In vitro corrosion tests were conducted on Nitinol alloys in accordance with ASTM F 2129-08. The metal ions released into the electrolyte during corrosion tests were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). Biocompatibility was assessed by observing the growth of human umbilical vein endothelial cells (HUVEC) on the surface of Nitinol alloys. Static and dynamic immersion tests were performed by immersing the Nitinol alloys in cell culture media and measuring the amount of metal ions released in solution. Sulforhodamine B (SRB) assays were performed to elucidate the effect of metal ions on the growth of HUVEC cells. The surfaces of the alloys were studied using Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS) respectively. Finally, wettability and surface energy were measured by Contact Angle Meter, whereas surface roughness was measured by Atomic Force Microscopy (AFM). All the surface treated alloys exhibited high resistance to corrosion when compared with untreated alloys. SRB assays revealed that Ni and Cu ions exhibited greater toxicity than Cr, Ta and Ti ions on HUVEC cells. EP and MEP alloys possessed relatively smooth surfaces and some were composed of nickel oxides instead of elemental nickel as determined by XPS. MEP exhibited lowest surface energy and lowest surface roughness.
Resumo:
The purpose of this study is to identify and analyze the basic causes of food service employee turnover in five selected restaurants in the Miami area. The withdrawal behavior in this study is treated in terms of controllable turnover, for the purpose of management, learning more about what action to take to solve this problem which has eaten into the fabric of the hospitality industry. The aim is to find out from the food service employees and management view of work for the purpose of identifying the variables which cause an employee to voluntarily leave a job. The objective is therefore, to analyze and describe the problem of labor turnover in these selected restaurants. Such description must precede efforts to arrive at solutions to the problem if these efforts are ever to be more than haphazard and superficial. Sigmund Freud once stated: "The true beginning of scientific activity consists in describing phenomena and only then in proceeding to group, classify and correlate them."1 The nature of the study is basically descriptive survey. Data is collected by the use of management questionnaire, food service employee questionnaire and finally employees job description index. The survey consisted of a series of well defined questions with open and closed endings dealing with employee with employee turnover. As Robert Ferber and P. J. Verdoom state in their book titled Research Method in Economics of Business: "Structured questionnaires, by supplying question formulations in very specific terms as well as the different possible answers are easier for the sample members to answer and also serve to reduce the danger of interviewer bias."2 The answers to the prepared questionnaire by sample members were then recorded. The results of the questionnaire responses were then compiled for presentation and analysis. 1 Julian Simon, Basic Research Methods in Social Science. Random House, New York, 1969, p.53. 2 Robert J. Ferber and P.J. Verdoon, Research Methods in Economics and Business, The McMillan Company, 1962, p. 20 9 .
Resumo:
Historically, memory has been evaluated by examining how much is remembered, however a more recent conception of memory focuses on the accuracy of memories. When using this accuracy-oriented conception of memory, unlike with the quantity-oriented approach, memory does not always deteriorate over time. A possible explanation for this seemingly surprising finding lies in the metacognitive processes of monitoring and control. Use of these processes allows people to withhold responses of which they are unsure, or to adjust the precision of responses to a level that is broad enough to be correct. The ability to accurately report memories has implications for investigators who interview witnesses to crimes, and those who evaluate witness testimony. This research examined the amount of information provided, accuracy, and precision of responses provided during immediate and delayed interviews about a videotaped mock crime. The interview format was manipulated such that a single free narrative response was elicited, or a series of either yes/no or cued questions were asked. Instructions provided by the interviewer indicated to the participants that they should either stress being informative, or being accurate. The interviews were then transcribed and scored. Results indicate that accuracy rates remained stable and high after a one week delay. Compared to those interviewed immediately, after a delay participants provided less information and responses that were less precise. Participants in the free narrative condition were the most accurate. Participants in the cued questions condition provided the most precise responses. Participants in the yes/no questions condition were most likely to say “I don’t know”. The results indicate that people are able to monitor their memories and modify their reports to maintain high accuracy. When control over precision was not possible, such as in the yes/no condition, people said “I don’t know” to maintain accuracy. However when withholding responses and adjusting precision were both possible, people utilized both methods. It seems that concerns that memories reported after a long retention interval might be inaccurate are unfounded.
Resumo:
High-stakes testing and accountability have infiltrated the education system in the United States; the top priority for all teachers must be student progress on standardized tests. This has resulted in the predominance of reading for test-taking, (efferent reading), in the English, language arts, and reading classrooms. Authentic uses of print activities, like aesthetic reading, that encourage students to engage individually with a text, have been pushed aside. During a 3-week time period, regular level, English 3/American literature students in a Title I magnet high school, participated in this quasi-experimental study (N = 62). It measured the effects of an intervention of reading American literature texts aesthetically and writing aesthetically-evoked reader responses on students’ self-efficacy beliefs regarding their comprehension of American literature. One trained teacher and the researcher participated in the study: student participants were pre- and post- tested using the Confidence in Reading American Literature Survey which examined their self-efficacy beliefs regarding their comprehension of American literature. Several statistical analyses were performed. The results of the linear regression analyses partially supported a positive relationship between aesthetically-evoked reader responses and students’ self-efficacy beliefs regarding their comprehension of American literature. Additionally, the results of the 2 (sex) x 2 (treatment) ANCOVAs conducted to test group differences in self-efficacy beliefs regarding the comprehension of American literature between treatment and control groups indicated a main effect for treatment (but not sex; nor was there a significant sex x treatment interaction), suggesting the treatment was partially effective in increasing students’ self-efficacy beliefs. Seven of the twelve ANCOVAs indicated a statistically significant increase in the treatment group’s adjusted group mean self-efficacy belief scores as a result of being exposed to the intervention. In six of these seven analyses, increases in self-efficacy beliefs occurred in tasks that required three or more higher-order levels of thinking/learning. The results are discussed in terms of theoretical, empirical and practical significance. Future research is recommended to extend the intervention beyond the narrow confines of a Title I magnet school to settings where the intervention could be tested longitudinally, e. g., honors and gifted students, elementary and middle schools.
Resumo:
The eggs of the dengue fever vector Aedes aegypti possess the ability to undergo an extended quiescence period hosting a fully developed first instar larvae within its chorion. As a result of this life history stage, pharate larvae can withstand months of dormancy inside the egg where they depend on stored reserves of maternal origin. This adaptation known as pharate first instar quiescence, allows A. aegypti to cope with fluctuations in water availability. An examination of this fundamental adaptation has shown that there are trade-offs associated with it. Aedes aegypti mosquitoes are frequently associated with urban habitats that may contain metal pollution. My research has demonstrated that the duration of this quiescence and the extent of nutritional depletion associated with it affects the physiology and survival of larvae that hatch in a suboptimal habitat; nutrient reserves decrease during pharate first instar quiescence and alter subsequent larval and adult fitness. The duration of quiescence compromises metal tolerance physiology and is coupled to a decrease in metallothionein mRNA levels. My findings also indicate that even low levels of environmentally relevant larval metal stress alter the parameters that determine vector capacity. My research has also demonstrated that extended pharate first instar quiescence can elicit a plastic response resulting in an adult phenotype distinct from adults reared from short quiescence eggs. Extended pharate first instar quiescence affects the performance and reproductive fitness of the adult female mosquito as well as the nutritional status of its progeny via maternal effects in an adaptive manner, i.e., anticipatory phenotypic plasticity results as a consequence of the duration of pharate first instar quiescence and alternative phenotypes may exist for this mosquito with quiescence serving as a cue possibly signaling the environmental conditions that follow a dry period. M findings may explain, in part, A. aegypti’s success as a vector and its geographic distribution and have implications for its vector capacity and control.