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The Effects of a Computer-mediated Intervention on "At-risk" Preschool Students' Receptive Vocabulary and Computer Literacy Skills.

The Effects of a Computer-mediated Intervention on "At-risk" Preschool Students' Receptive Vocabulary and Computer Literacy Skills.

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Date: December 2003
Creator: Alman, Lourdes Fraga
Description: This study examined the effects of a computer-mediated intervention on "at-risk" preschool students' receptive vocabulary development, computer-literacy skills, and enthusiasm for leaning. Twenty-two preschool-aged children attending an urban primary public school and participating in government subsidized school lunch program participated in the study. A pretest/posttest control-group design and case-study participant observations were used for data collection. Students were assigned to one of two treatment groups. Eleven preschool students with pretest School Readiness Composite (SRC) standard scores of 80, or below, on the Bracken Basic Concept Scale-Revised (BBCS-R), were assigned to the intervention group. Eleven pre-school students matched by age level and teacher comprised the comparison group. The intervention group received computer-mediated instruction while the comparison group received classroom teacher instruction. The first research question examined the effect of the intervention on students' receptive vocabulary analyzing groups' pretest and posttest BBCS-R School Readiness Composite mean scores. Combined analysis of a Two-Factor Repeated Measures and a Posttest only ANCOVA revealed that computer-mediated instruction was as effective as classroom teacher instruction in helping "at-risk" students acquire readiness receptive vocabulary. The second research question examined the effect of the intervention on "at-risk" student's computer-literacy skills analyzing participants pretest and posttest mean scores on the ...
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The Effects of a Remote Control Tactile Feedback System on Conversation Skills in Children with Autism.

The Effects of a Remote Control Tactile Feedback System on Conversation Skills in Children with Autism.

Date: December 2003
Creator: Shively, Jane M.
Description: A few studies have examined the effects of a remote control tactile device (RCT) as an unobtrusive prompting method used to promote skills such as verbal initiations and play behaviors in children with autism. To date, however, no published studies have investigated the effects of the RCT as a consequence to increase and maintain conversation skills. This study was designed to determine whether the RCT, in conjunction with common training techniques (i.e. roleplays, visual feedback, and sibling coaching), could be used as a discrete and unobtrusive feedback system to promote conversation skills in high functioning children with autism. Results found that the RCT and training packages were effective in initially increasing rates of target responses. The effects however, did not always maintain with a return to baseline. Programming "naturally" maintaining communities of reinforcement was found to be a critical factor in the maintenance of the conversational responses.
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The Effects of an Intensive Format of the Landreth Filial Therapy Training Model Compared to the Traditional Landreth Filial Therapy Model

The Effects of an Intensive Format of the Landreth Filial Therapy Training Model Compared to the Traditional Landreth Filial Therapy Model

Date: December 2003
Creator: Ferrell, Lisa G.
Description: This research study investigated the effectiveness of an intensive format of the traditional Landreth filial therapy training (LFTT) model compared to the traditional LFTT model. Specifically, this study compared the intensive LFTT group and the traditional LFTT group at post-testing in the areas of: (a) reducing stress related to parenting, (b) increasing parental empathic behavior with their children, (c) increasing parental acceptance toward their children, and (d) reducing perceived child behavior problems. The traditional LFTT group consisted of 13 parents in groups of up to six members for 10 90-minute weekly sessions. Traditional LFTT involved didactic instruction, required at-home laboratory playtimes, and supervision. Parents were taught child-centered play therapy skills of responsive listening, recognizing children's emotional needs, therapeutic limit setting, building children's self-esteem, and structuring required weekly playtimes with their children using a kit of specially selected toys. The intensive LFTT group consisted of 13 parents in groups of up to four members who met on four Saturdays for 4 hours each. The traditional LFTT model was modified to teach the same material over fewer sessions. The difference in this delivery was fewer opportunities for parents to have home playtimes and receive feedback from the researcher. To compensate for this ...
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The Effects of "Errorless" Training and Testing on the Performances of Typically Developing Children During Acquisition and Retention.

The Effects of "Errorless" Training and Testing on the Performances of Typically Developing Children During Acquisition and Retention.

Date: December 2003
Creator: Arnadottir, Iris
Description: This study examines the effects of two teaching procedures and two testing procedures (“Skip” and “Guess”) on acquisition, retention and generalization of learning. Three typically developing females between the ages of 8 and 11 learned the 24 lower case letters of the Greek alphabet. Half of the letters were taught with the “Skip” procedure and the other half with the “Guess” procedure. The “Skip” procedure produced faster and more efficient learning than the “Guess” procedure. The “Skip” procedure also resulted in better initial retention (4 weeks), but this effect disappeared in subsequent retention tests. The training conditions did not have differential effects on generalization tests across learning channels, except for the Free/Say channel.
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Effects of Tenderness on Problem Solving.

Effects of Tenderness on Problem Solving.

Date: December 2003
Creator: Kalawski, Juan Pablo
Description: The purpose of this study was to determine the effects of tenderness on problem solving. Thirty-four female undergraduates participated. In the experimental condition, participants received instructions to reproduce a specific respiratory-posturo-facial pattern that had induced tenderness in previous studies. Participants in the control condition performed a non-emotional exercise. After either the pattern or the control exercise, participants completed one of two jigsaw puzzles. One puzzle had only an empty room while the other had a family scene. For participants who worked on the room puzzle, the tenderness pattern led to longer completion times. In contrast, for participants who worked on the family puzzle, the tenderness pattern led to shorter completion times.
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The Effects of Workshop Training and Coaching on the Acquisition and Generalization of Teaching Skills

The Effects of Workshop Training and Coaching on the Acquisition and Generalization of Teaching Skills

Date: December 2003
Creator: Almon, Holly C.
Description: The purpose of this study was threefold: (a) to examine the separate effects of increased accuracy on multiple-choice/rank-order written tests and coaching on the teaching performance of participants; (b) to compare generalization across tasks produced by the workshop and coaching; and (c) to assess maintenance of teaching performance. Following baseline, two adults received a lecture on discrete trial teaching procedures. A written test measured verbal performance on workshop material periodically throughout this phase. During the next phase, each adult then experienced further training via in-situ coaching. A multiple baseline design across tasks was used during the coaching phase. Results of the workshop training package revealed an inverse relationship between the strongest verbal performance and strongest teaching performance skill areas. In addition, only with the introduction of the in-situ coaching package did teacher performance improve significantly across all behaviors. Child responding remained relatively constant throughout the study, regardless of teacher performance. Some generalization of teacher behavior was observed across tasks, but was extremely variable across both workshop and coaching conditions. After the cessation of coaching, teacher performance remained stable across maintenance phases and at a 6-week follow-up.
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Electrochemical synthesis of CeO2 and CeO2/montmorillonite nanocomposites.

Electrochemical synthesis of CeO2 and CeO2/montmorillonite nanocomposites.

Date: December 2003
Creator: Wang, Qi
Description: Nanocrystalline cerium oxide thin films on metal and semiconductor substrates have been fabricated with a novel electrodeposition approach - anodic oxidation. X-ray diffraction analysis indicated that as-produced cerium oxide films are characteristic face-centered cubic fluorite structure with 5 ~ 20 nm crystal sizes. X-ray photoelectron spectroscopy study probes the non-stoichiometry property of as-produced films. Raman spectroscopy and Scanning Electron Microscopy have been applied to analyze the films as well. Deposition mode, current density, reaction temperature and pH have also been investigated and the deposition condition has been optimized for preferred oriented film formation: galvanostatic deposition with current density of -0.06 mA/cm2, T > 50oC and 7 < pH < 10. Generally, potentiostatic deposition results in random structured cerium oxide films. Sintering of potentiostatic deposited cerium oxide films leads to crystal growth and reach nearly full density at 1100oC. It is demonstrated that in-air heating favors the 1:2 stoichiometry of CeO2. Nanocrystalline cerium oxide powders (4 ~ 10 nm) have been produced with anodic electrochemical synthesis. X-ray diffraction and Raman spectroscopy were employed to investigate lattice expansion phenomenon related to the nanoscale cerium oxide particles. The pH of reaction solution plays an important role in electrochemical synthesis of cerium oxide films ...
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Embedded monitors for detecting and preventing intrusions in cryptographic and application protocols.

Embedded monitors for detecting and preventing intrusions in cryptographic and application protocols.

Date: December 2003
Creator: Joglekar, Sachin P.
Description: There are two main approaches for intrusion detection: signature-based and anomaly-based. Signature-based detection employs pattern matching to match attack signatures with observed data making it ideal for detecting known attacks. However, it cannot detect unknown attacks for which there is no signature available. Anomaly-based detection builds a profile of normal system behavior to detect known and unknown attacks as behavioral deviations. However, it has a drawback of a high false alarm rate. In this thesis, we describe our anomaly-based IDS designed for detecting intrusions in cryptographic and application-level protocols. Our system has several unique characteristics, such as the ability to monitor cryptographic protocols and application-level protocols embedded in encrypted sessions, a very lightweight monitoring process, and the ability to react to protocol misuse by modifying protocol response directly.
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Enigmatic Realms

Enigmatic Realms

Date: December 2003
Creator: Malik, Irum
Description: The use of copper in my work has opened up an entirely new conceptual and esthetic world. I have expanded my vocabulary of visual imagery based on the nature of how copper reacts with fire. The organic beauty harmonizes so gracefully with the manufactured material. This new material has certainly opened up a refreshing platform on which to further develop my ideas.
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Fabrication and light scattering study of multi-responsive nanostructured hydrogels and water-soluble polymers.

Fabrication and light scattering study of multi-responsive nanostructured hydrogels and water-soluble polymers.

Date: December 2003
Creator: Xia, Xiaohu
Description: Monodispersed microgels composed of poly-acrylic acid (PAAc) and poly(N-isopropylacrylamide) (PNIPAM) interpenetrating networks were synthesized by 2-step method with first preparing PNIPAM microgel and then polymerizing acrylic acid that interpenetrates into the PNIPAM network. The semi-dilute aqueous solutions of the PNIPAM-PAAc IPN microgels exhibit an inverse thermo-reversible gelation. Furthermore, IPN microgels undergo the reversible volume phase transitions in response to both pH and temperature changes associated to PAAc and PNIPAM, respectively. Three applications based on this novel hydrogel system are presented: a rich phase diagram that opens a door for fundamental study of phase behavior of colloidal systems, a thermally induced viscosity change, and in situ hydrogel formation for controlled drug release. Clay-polymer hydrogel composites have been synthesized based on PNIPAM gels containing 0.25 to 4 wt% of the expandable smectic clay Na-montmorillonite layered silicates (Na-MLS). For Na-MLS concentrations ranging from 2.0 to 3.2 wt%, the composite gels have larger swelling ratio and stronger mechanical strength than those for a pure PNIPAM. The presence of Na-MLS does not affect the value of the lower critical solution temperature (LCST) of the PNIPAM. Surfactant-free hydroxypropyl cellulose (HPC) microgels have been synthesized in salt solution. In a narrow sodium chloride concentration range from 1.3 ...
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Fashion Circles

Fashion Circles

Date: December 2003
Creator: Öhrn, Linda
Description: Through this body of work and this paper the possibilities of using Fashion Design to express the concepts of the circle has been explored. This was done with three questions in mind: How can I use the shape of the circle as inspiration for fashion design? How can I express related words and phrases in my design? and How can I use the colors black and white to emphasize the concept of my design. To answer these questions I have created two groups of garments: one was inspired by circular objects, such as cherries and drops, and the other starting from words and phrases such as "study circle" and "circle the wagons." In the first group the emphasis was on the aesthetics of the garment while the second group was more focused on meaning. All garments are black and white.
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Feminist Design Methodology: Considering the Case of Maria Kipp

Feminist Design Methodology: Considering the Case of Maria Kipp

Date: December 2003
Creator: Lawrence, Anne
Description: This thesis uses the work and career of the textile designer Maria Kipp to stage a prolegomena concerning how to write about a female designer active during the middle of the twentieth century. How can design historians incorporate new methodologies in the writing of design history? This thesis explores the current literature of feminist design history for solutions to the potential problems of the traditional biography and applies these to the work and career of Kipp. It generates questions concerning the application of methodologies, specifically looking at a biographical methodology and new methodologies proposed by feminist design historians. Feminist writers encourage scholarship on unknown designers, while also they call for a different kind of writing and methodology. The goal of this thesis is to examine how these new histories are written and in what ways they might inspire the writing of Kipp into design history.
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Filial Therapy with Israeli Parents

Filial Therapy with Israeli Parents

Date: December 2003
Creator: Kidron, Michal
Description: The purpose of this study was to determine the effectiveness of an intensive version of the Landreth (2002) 10-week filial therapy model as a method of intervention for children of Israeli parents living in Israel. This study was designed to determine the effectiveness of intensive filial therapy training in (a) reducing internalizing behavior problems of Israeli children; (b) reducing externalizing behavior problems of Israeli children; and (c) reducing overall behavior problems of Israeli children. A second purpose of this study was to determine the effectiveness of intensive filial therapy training with Israeli parents in increasing the parents' (a) empathic responsiveness with their children; (b) communication of acceptance to their children; (c) allowance of self-direction by their children; (d) involvement in their children's play activities; (e) feelings of efficacy as parents; and (f) reduction of parental stress. The experimental group consisted of fourteen Israeli children who their parents received nine intensive Filial Therapy training sessions within a five week period and had seven parent-child play sessions. The non-treatment comparison group consisted of thirteen Israeli children whose parents received no treatment. Parents in the study completed the Hebrew version of the Child Behavior Checklist, the Parenting Stress Index, and conducted pre-test and ...
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From Stockyards to Defense Plants, the Transformation of a City: Fort Worth, Texas, and World War II

From Stockyards to Defense Plants, the Transformation of a City: Fort Worth, Texas, and World War II

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Date: December 2003
Creator: Pinkney, Kathryn Currie
Description: World War II represented a watershed event in the history of the United States and affected political, economic, and social systems at all levels. In particular, the war unleashed forces that caused rapid industrialization, immigration, and urbanization in two regions, the South and the West. This study examines one community's place in that experience as those forces forever altered the city of Fort Worth, Texas. Prior to World War II, Fort Worth's economy revolved around cattle, food-processing, and oil, industries that depended largely on an unskilled labor force. The Fort Worth Stockyards laid claim to the single largest workforce in the city, while manufacturing lagged far behind. After an aggressive campaign waged by city civic and business leaders, Fort Worth acquired a Consolidated Aircraft Corporation assembly plant in early 1941. The presence of that facility initiated an economic transformation that resulted in a major shift away from agriculture and toward manufacturing, particularly the aviation industry. The Consolidated plant sparked industrial development, triggered an influx of newcomers, trained a skilled workforce, and stimulated an economic recovery that lifted the city out of the Depression-era doldrums. When hostilities ended and the United States entered the Cold War period, Consolidated and the adjacent ...
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The gathering and use of information by fifth grade students with access to Palm® handhelds.

The gathering and use of information by fifth grade students with access to Palm® handhelds.

Date: December 2003
Creator: Peet, Martha Stuart Williamson
Description: Handheld computers may hold the possibility for a one-to-one computer: student ratio. The impact of the use of Palm® (Palm, Inc.) handhelds on information acquisition and use by 5th grade students in a North Texas school during a class research project was investigated. Five research questions were examined using observation, interviews, surveys, and document analysis. Are there differences in information gathering and use with the Palm between gifted, dyslexic, and regular learners? What relevance criteria do students use to evaluate a web site to determine whether to download the site to the Palm and afterwards whether to use the downloaded site's information in the report? How do the Palms affect the writing process? Do the animations and concept maps produced on the Palm demonstrate understanding of the intended concepts? Are there significant differences in results (i.e., final products grade) between Palm users and non-Palm users? Three groups of learners in the class, gifted, dyslexic, and regular learners, participated in the study. The regular and dyslexic students reported using Web sites that had not been downloaded to the Palm. Students reported several factors used to decide whether to download Web sites, but the predominant deciding factor was the amount of information. ...
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Harmonization of Accounting Practices Among IAS Firms Listed in the U.S. and Its Capital Market Implications

Harmonization of Accounting Practices Among IAS Firms Listed in the U.S. and Its Capital Market Implications

Date: December 2003
Creator: Paananen, Mari
Description: The focus of the study is on financial reporting for non-U.S. firms registered with the Securities Exchange Commission (SEC) but using International Accounting Standards (IAS). This study addresses two issues, (1) whether the comparability of financial reporting among firms using IAS in credit and equity financing jurisdictions increases over time and (2) the associated capital market implications. The motivation for the study is the SEC's ongoing assessment of IAS for possible use by non-U.S. registrants for listing and capital raising in the U.S. Previous research on variations in financial reporting practices has revealed distinctly different types of financial reporting depending on country of origin. Moreover, some research suggests that such differences in financial reporting tend to persist in spite of harmonization efforts of accounting standards. This study suggests that there may be a systematic difference between credit and equity firms' financial reporting that is manifested by the fact that credit firms' adjustments to U.S. GAAP are greater than the adjustments made by equity firms. This systematic difference has had the following capital market consequences for credit firms, (1) a decreasing strength of association between accounting earnings and share prices post-1994, (2) an increased bid-ask spread post-1994, and (3) a decreased ...
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High school string orchestra teacher as a career choice: A survey of 11th- and 12th-grade high school string orchestra students in Texas.

High school string orchestra teacher as a career choice: A survey of 11th- and 12th-grade high school string orchestra students in Texas.

Date: December 2003
Creator: Brumbaugh, Sherron M.
Description: The purpose of this study was to describe 11th- and 12th-grade high school string orchestra students in Texas public schools in terms of their decision to enter the field of string orchestra teaching as a possible career choice or to pursue another field of study. Convenience sampling techniques were used to secure a study population of 1,683 high school string orchestra students. The Junior and Senior High School String Orchestra Student Survey (researcher designed) was used to gather demographic characteristics, students' perceptions on selected intrinsic/extrinsic work values, tangible elements of teaching, intrinsic characteristics of string orchestra teaching, and individuals assisting in students' career choices. Selected elements of teaching cited by students for their lack of interest in string orchestra teaching were also reviewed. Analysis procedures for descriptive statistics included measures of central tendency, crosstabulation, frequencies and percentages. Consistent with prior research, it was found that a larger number of female students over male students were interested in string orchestra teaching. Students interested in fields outside of string orchestra teaching reported higher class grades, more honors and advanced classes and higher SAT/ACT mean scores. Students interested in string orchestra teaching reported a higher percentage of brothers/sisters, mothers and fathers who played ...
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The impact of alternative school intervention on subsequent student performance in the mainstream school environment.

The impact of alternative school intervention on subsequent student performance in the mainstream school environment.

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Date: December 2003
Creator: Galloway, Cathleen
Description: The purpose of this study was to analyze the impact of alternative school intervention on subsequent student performance. The literature review examined the history and development of alternative schools, the legislation pertaining to alternative schools, and related studies. The population consisted of students placed in the discipline alternative education program (DAEP) of an alternative school located in a large suburban school district in north Texas. Students placed in DAEP in the spring semester of 2001 in grades 7, 8, 9, and 10 were included in the sample. Data on student success was gathered for the one semester prior to placement (pre-intervention) and for the two semesters after placement (post-intervention). Student success was measured in terms of course grade averages and attendance. The student sample was divided into the following subgroups: grade level, sex, ethnicity, and qualification for the school meal program. The students' grade averages were compared within the subgroups utilizing a one-way analysis of variance (ANOVA). Tukey's post hoc comparison was utilized on the groups when ANOVA was found to be significant. The students' attendance was analyzed by comparing the proportion of days attended in each of the three semesters included in the study. A normal test of two ...
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The impact of computer assisted instruction on sensory cognitive factors in literacy learning.

The impact of computer assisted instruction on sensory cognitive factors in literacy learning.

Date: December 2003
Creator: Walton, Donna L.
Description: The purpose of this study was to examine the impact of computer assisted instruction on the development of literacy skills. The effect of instructional methodologies designed to stimulate sensory processing (auditory, visual, and somatic sensory) through information processing activities was analyzed. A software program was designed to present instruction to stimulate learning in one sensory modality, visual processing. Also, the effect of delivery mechanisms on the acquisition of literacy skills was investigated. Three treatment groups and a control group were established to analyze differences: cognitive processing methodologies presented via computer technology, conventional methodologies presented via computer technology, cognitive processing methodologies presented through traditional classroom tools, and a control group. A portable keyboard computer with word processing capabilities was selected to deliver technology-enhanced instruction. Results from this study suggest that activities designed to specifically promote processing in one sensory modality, do not promote acquisition of skills in other regions. There was no change in scores when visual methodologies were applied to auditory and somatic sensory cognitive processing goals. When spelling tests that utilized all sensory modalities were analyzed, visual processing instruction had no effect on achievement. This result was duplicated when tests requiring auditory processing skills were examined. However, when visual ...
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The Impact of Middle Class Economic Strength on Civil Liberties Performance and Domestic and External Peace

The Impact of Middle Class Economic Strength on Civil Liberties Performance and Domestic and External Peace

Date: December 2003
Creator: Stedman, Joseph B.
Description: Using data for 93 countries from 1972 through 2001 in cross-national analysis, this study compares the relative economic strength of a country's middle-class with its civil liberties performance and its history of domestic and external conflict. For purposes of this analysis, the relative strength of a country's middle-class is determined by multiplying the square root of a country's gross domestic product per capita by the percentage of income distributed to the middle 60 % of the population (middle class income share). Comparisons between this measure of per capita income distributed (PCID) and several other indicators show the strength of the relationship between PCID and civil liberties performance and domestic and external conflict. In the same manner, comparisons are made for the middle class income share (MCIS) alone. The countries are also divided by level of PCID into 3 world classes of 31 countries each for additional comparisons. In tests using bivariate correlations, the relationships between PCID and MCIS are statistically significant with better civil liberties performance and fewer internal conflicts. With multivariate regression the relationship between PCID and civil liberties performance is statistically significant but not for PCID and internal conflict. As expected, in both correlations and regression between PCID ...
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The impact of technical barriers on the effectiveness of professional development as related to a distance education system-based course: A case study in the Web World Wonders environmental science learning community.

The impact of technical barriers on the effectiveness of professional development as related to a distance education system-based course: A case study in the Web World Wonders environmental science learning community.

Date: December 2003
Creator: Dawson, John L.
Description: This study reports and discusses the impact of technical barriers on the effectiveness of professional development as related to a distance education system based course: a case study of the web world wonders environmental science learning community in Florida. The project involved 4th through 12th grade public school teachers learning how to use GPS readers, digital cameras, and Arc View software for the purpose of utilizing a Website that enabled remote Internet camera access in Florida State Parks. Under the supervision of Florida State University and the Florida Department of Education those teachers received professional development in techniques for developing lesson plans utilizing the equipment and software as stated above. Using the Concept Based Adoption Model, a description of the teacher's demographics, Levels of Use and Stages of Concern with relation to gender, age, teaching experience, and technological experience was examined. Technical barriers were identified and an explanation of how they were overcome in the process of receiving the professional development is reported.
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Improved Approximation Algorithms for Geometric Packing Problems With Experimental Evaluation

Improved Approximation Algorithms for Geometric Packing Problems With Experimental Evaluation

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Date: December 2003
Creator: Song, Yongqiang
Description: Geometric packing problems are NP-complete problems that arise in VLSI design. In this thesis, we present two novel algorithms using dynamic programming to compute exactly the maximum number of k x k squares of unit size that can be packed without overlap into a given n x m grid. The first algorithm was implemented and ran successfully on problems of large input up to 1,000,000 nodes for different values. A heuristic based on the second algorithm is implemented. This heuristic is fast in practice, but may not always be giving optimal times in theory. However, over a wide range of random data this version of the algorithm is giving very good solutions very fast and runs on problems of up to 100,000,000 nodes in a grid and different ranges for the variables. It is also shown that this version of algorithm is clearly superior to the first algorithm and has shown to be very efficient in practice.
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Influence of Cholesterol Import on  Aspergillus fumigatus Growth and Antifungal Suscepibility

Influence of Cholesterol Import on Aspergillus fumigatus Growth and Antifungal Suscepibility

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Date: December 2003
Creator: Hassan, Saad A.
Description: Invasive pulmonary aspergillosis is a life-threatening fungal infection commonly observed in immunocompromised patients and has a mortality rate approaching 100% once the disease is disseminated. Aspergillus fumigatus is the most common pathogen. Early diagnosis improves the prognosis but is very difficult since most signs and symptoms are nonspecific. Antifungal therapy, usually based on sterol biosynthesis inhibitors, is also of limited efficacy. In my attempts to discover a diagnostic sterol marker for aspergillosis, I observed that A. fumigatus incorporates large amounts of cholesterol from serum-containing medium. This observation suggested the hypothesis that exogenous cholesterol from the host can be imported by A. fumigatus and used as a substitute for ergosterol in the cell membrane. This proposed mechanism would reduce the efficacy of antifungal drugs that act as sterol biosynthesis inhibitors. Experiments to test this hypothesis were designed to determine the effects of serum-free and serum-containing medium on growth of A. fumigatus in the presence and absence of azole antifungal agents. The results showed a marked increase in growth in the presence of human serum. Cultures in media containing cholesterol but no serum also showed enhanced growth, a result indicating that a non-cholesterol component of serum is not primarily responsible for the ...
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Integrating GIS with Benthic Metrics: Calibrating a Biotic Index to Effectively Discriminate Stream Impacts in Urban Areas of the Blackland Prairie Eco-Region

Integrating GIS with Benthic Metrics: Calibrating a Biotic Index to Effectively Discriminate Stream Impacts in Urban Areas of the Blackland Prairie Eco-Region

Date: December 2003
Creator: Earnest, Steven F. P.
Description: Rapid Bioassessment Protocols integrate a suite of community, population, and functional metrics, determined from the collection of benthic macroinvertebrates or fish, into a single assessment. This study was conducted in Dallas County Texas, an area located in the blackland prairie eco-region that is semi-arid and densely populated. The objectives of this research were to identify reference streams and propose a set of metrics that are best able to discriminate between differences in community structure due to natural variability from those caused by changes in water quality due to watershed impacts. Using geographic information systems, a total of nine watersheds, each representing a different mix of land uses, were chosen for evaluation. A total of 30 metrics commonly used in RBP protocols were calculated. Efficacy of these metrics to distinguish change was determined using several statistical techniques. Ten metrics were used to classify study area watersheds according to stream quality. Many trends, such as taxa presence along habitat quality gradients, were observed. These gradients coincided with expected responses of stream communities to landscape and habitat variables.
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