Baeyer-Villiger Oxidation of 1,7- & 1,9-dibromopentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione

Access: Use of this item is restricted to the UNT Community
Baeyer-Villiger oxidation of 1,9-dibromopentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione (1,9-dibromo-PCU-8,11-dione) was performed by using an excess amount of m-chloroperbenzoic acid (3 equivalents) and resulted in the formation of the corresponding monolactone. The reaction would not proceed to the dilactone stage. The structure of the reaction product was established unequivocally via single crystal X-ray diffraction. Baeyer-Villiger oxidation of 1,9-dibromo-PCU-8,11-dione using ceric ammonium nitrate (CAN) was also performed and afforded a mixture of lactones. Only one of these lactones, which also contained an alkene functionality, could be isolated and characterized. 1,7-dibromo-PCU-8,11-dione was also reacted with CAN, yielding the mono-lactone, which has also been characterized.
Date: May 2004
Creator: Akinola, Adeniyi O.
System: The UNT Digital Library

Evaluation of virulence in wild type and pyrimidine auxotrophs of Pseudomonas aeruginosa using the eukaryotic model system Caenorhabditis elegans.

Access: Use of this item is restricted to the UNT Community
The human opportunistic pathogen, Pseudomonas aeruginosa PAO1, has been shown to kill the nematode Caenorhabditis elegans. C. elegans has been a valuable model for the study of bacterial pathogenesis, and has reinforced the notion that common virulence and host defense mechanisms exist. Recently, the pyrimidine pathway was shown to regulate virulence levels. Therefore, mutations in the pyrimidine pathway of PAO1 showed decrease virulence in the nematode. When starving the nematode, bacterial resistance was also shown to increase. It was hypothesized that starvation induced the DAF pathway, which regulates the transcription of genes involved with the antibacterial defense mechanism. Further research will be conducted to test this theory by performing RNAi experiments for the genes functioning in the antibacterial defense mechanism.
Date: August 2004
Creator: Anvari, Sara
System: The UNT Digital Library

The Effect of Information Literacy Instruction on Library Anxiety Among International Students

Access: Use of this item is restricted to the UNT Community
This study explored what effect information literacy instruction (ILI) may have on both a generalized anxiety state and library anxiety specifically. The population studied was international students using resources in a community college. Library anxiety among international students begins with certain barriers that cause anxiety (i.e., language/communication barriers, adjusting to a new education/library system and general cultural adjustments). Library Anxiety is common among college students and is characterized by feelings of negative emotions including, ruminations, tension, fear and mental disorganization (Jiao & Onwuegbuzie, 1999a). This often occurs when a student contemplates conducting research in a library and is due to any number of perceived inabilities about using the library. In order for students to become successful in their information seeking behavior this anxiety needs to be reduced. The study used two groups of international students enrolled in the English for Speakers of other Languages (ESOL) program taking credit courses. Each student completed Bostick's Library Anxiety Scale (LAS) and Spielberger's State-Trait Anxiety Inventory (STAI) to assess anxiety level before and after treatment. Subjects were given a research assignment that required them to use library resources. Treatment: Group 1 (experimental group) attended several library instruction classes (the instruction used Kuhltau's information search …
Date: May 2004
Creator: Battle, Joel C.
System: The UNT Digital Library

Wayfinding tools in public library buildings: A multiple case study.

Access: Use of this item is restricted to the UNT Community
Wayfinding is the process of using one or more tools to move from one location to another in order to accomplish a task or to achieve a goal. This qualitative study explores the process of wayfinding as it applies to locating information in a public library. A group of volunteers were asked to find a selection of items in three types of libraries-traditional, contemporary, and modern. The retrieval process was timed and the reactions of the volunteers were recorded, documented, and analyzed. The impact of various wayfinding tools-architecture, layout, color, signage, computer support, collection organization-on the retrieval process was also identified. The study revealed that many of the wayfinding tools currently available in libraries do not facilitate item retrieval. Inconsistencies, ambiguities, obstructions, disparities, and operational deficiencies all contributed to end-user frustration and retrieval failure. The study suggests that failing to address these issues may prompt library patrons-end users who are increasingly interested in finding information with minimal expenditures of time and effort-may turn to other information-retrieval strategies and abandon a system that they find confusing and frustrating.
Date: May 2004
Creator: Beecher, Ann B.
System: The UNT Digital Library

Treatment efficacy in a chronic pain population: Pre- to post-treatment.

Access: Use of this item is restricted to the UNT Community
The purpose of the current study was to investigate the effects of a multidisciplinary pain management program on five measures of subjective psychosocial factors. Ninety-five participants in the comprehensive multidisciplinary treatment group and the standard medical intervention control group were surveyed about various psychosocial factors using Axis II of the West Haven - Yale Multidimensional Pain Inventory (MPI), pre- to post-treatment. It was hypothesized that post-treatment levels would be significantly lower than pre-treatment levels for all five psychosocial variables. Additionally, gender and ethnicity variables were examined. Based on preliminary analyses indicating pre-treatment differences between the experimental and control group, five 2 x 2 x 3 analyses of covariances (ANCOVAs) were used to examine the above hypotheses. Results indicated significant differences between the treatment conditions on measures of control, with the comprehensive group feeling more in control than the standard group at post-treatment. No other significant main effects for treatment condition were found on the measures of pain severity, interference with daily activities, negative mood, or social support. However, a significant gender main effect was found for social support at post-treatment, with females reporting more social support than males. A significant gender x ethnicity interaction was also found for post-treatment control, …
Date: December 2004
Creator: Bernstein, Dana N.
System: The UNT Digital Library

Hopfield Networks as an Error Correcting Technique for Speech Recognition

Access: Use of this item is restricted to the UNT Community
I experimented with Hopfield networks in the context of a voice-based, query-answering system. Hopfield networks are used to store and retrieve patterns. I used this technique to store queries represented as natural language sentences and I evaluated the accuracy of the technique for error correction in a spoken question-answering dialog between a computer and a user. I show that the use of an auto-associative Hopfield network helps make the speech recognition system more fault tolerant. I also looked at the available encoding schemes to convert a natural language sentence into a pattern of zeroes and ones that can be stored in the Hopfield network reliably, and I suggest scalable data representations which allow storing a large number of queries.
Date: May 2004
Creator: Bireddy, Chakradhar
System: The UNT Digital Library

City of Denton Municipal Solid Waste Characterization and Management Strategies

Access: Use of this item is restricted to the UNT Community
Due to concern about diminishing landfill space, the City of Denton contracted a municipal solid waste characterization study in 1999 that would identify materials for diversion. This paper describes the results of 5 1-week waste sorting events, a scale-house analysis, a recycling participation study, a recycler profile and a similar city study. The results of the characterization studies suggest that at least 50% of each waste stream is recyclable or divertible though paper products accounted for no more than 45% by weight of any waste stream. Curbside recycling participation rate was 71% during the 6-week study period though the average weekly set-out rate was 37%. Recycling participation rates varied significantly by zip code and by home value categories but not by gender. Denton is fairly progressive in its waste management approach when compared to demographically similar cities on a 15-question assessment though recommendations for improvement have been identified.
Date: May 2004
Creator: Brady, Patricia D.
System: The UNT Digital Library

The Effect of Breastfeeding Education on Breastfeeding Initiation Rates Among Teenage Mothers

Access: Use of this item is restricted to the UNT Community
The purpose of this study was to examine the effect of a breastfeeding education program on breastfeeding initiation rates, breastfeeding knowledge, and attitude towards breastfeeding among teenage mothers at an urban school for pregnant and parenting teens. Breastfeeding initiation rose from 35.7% in the control group to 85.2% in the treatment group. The mean score on the Breastfeeding Knowledge Subscale was significantly higher for the treatment group but not the control group. There was not a significant increase in mean scores on the Breastfeeding Attitude Subscale. Participants who initiated breastfeeding scored also had a significant increase in scores from pretest to posttest on the Breastfeeding Knowledge Subscale, while participants who did not initiate breastfeeding did not.
Date: May 2004
Creator: Brown, Amber L.
System: The UNT Digital Library

Development of a Novel Grease Resistant Functional Coatings for Paper-based Packaging and Assessment of Application by Flexographic Press

Access: Use of this item is restricted to the UNT Community
Recent commercial developments have created a need for alternative materials and methods for imparting oil/grease resistance to paper and/or paperboard used in packaging. The performance of a novel grease resistant functional coating comprised of polyvinyl alcohol (PVA), sodium tetraborate pentahydrate (borate) and acetonedicarboxylic acid (ACDA) and the application of said coating by means of flexographic press is presented herein. Application criteria is developed, testing procedures described, and performance assessment of the developed coating materials are made. SEM images along with contact angle data suggest that coating performance is probably attributable to decreased mean pore size in conjunction with a slightly increased surface contact angle facilitated by crosslinking of PVA molecules by both borate ions and ACDA.
Date: August 2004
Creator: Brown, Robert W.
System: The UNT Digital Library

Utilization of Corridor Habitat by White-tailed Deer (Odocoileus virginianus) in Denton County, Texas

Access: Use of this item is restricted to the UNT Community
White-tailed deer (Odocoileus virginianus) (N=15) movements were determined with use of radio telemetry techniques to determine the utilization of corridor habitat on the Lake Ray Roberts Greenbelt Corridor (RRGC) in north central Texas. Home ranges were calculated using three estimation types. Male white-tailed deer tend to have home ranges twice that of female home ranges. Seasonal home ranges were largest during spring (Feb. - April) and fall (Aug. - Oct.) seasons. Males had greater seasonal variation in utilization than females. No statistically significant difference (p=0.24) between white-tailed deer locations when the RRGC experiences heavy human traffic compared to days when there is light human traffic. Linearity indices indicated home ranges less linear than expected (LI = 3.02). The RRGC should be maintained at its current status to provide a variety of vegetational types and protective cover for white-tailed deer and other wildlife of Denton County.
Date: May 2004
Creator: Bruce, Troy Kenneth
System: The UNT Digital Library

De novo prediction of the ground state structure of transition metal complexes.

Access: Use of this item is restricted to the UNT Community
One of the main goals of computational methods is to identify reasonable geometries for target materials. Organometallic complexes have been investigated in this dissertation research, entailing a significant challenge based on transition metal diversity and the associated complexity of the ligands. A large variety of theoretical methods have been employed to determine ground state geometries of organometallic species. An impressive number of transition metals entailing diverse isomers (e.g., geometric, spin, structural and coordination), different coordination numbers, oxidation states and various numbers of electrons in d orbitals have been studied. Moreover, ligands that are single, double or triple bonded to the transition metal, exhibiting diverse electronic and steric effects, have been investigated. In this research, a novel de novo scheme for structural prediction of transition metal complexes was developed, tested and shown to be successful.
Date: December 2004
Creator: Buda, Corneliu
System: The UNT Digital Library

Biogeography of Montane Mammals on the Colorado Plateau and Adjacent Regions

Access: Use of this item is restricted to the UNT Community
This study identifies the biogeographic factors that structure small mammal communities on mountains of the Colorado Plateau and adjacent regions. Forty six isolated ranges were characterized across a 5-state study area encompassing the Colorado Plateau, including the central high plateaus of Utah and the Basin and Range Province (i.e. the Great Basin and mountains of Arizona and New Mexico). Presence/absence data of 25 montane mammal species were used to explore the interactions between historical and ecological processes affecting local and regional diversity patterns. Multivariate analyses, such as non-metric dimensional scaling, were used to explore factors which influence community composition. Results of these analyses revealed the Colorado River as a significant biogeographic barrier that affects montane mammal community structure. MtDNA cytochrome b sequence variation was analyzed among populations of the long-tailed vole, Microtus longicaudus, sampled from five interior ranges of the Colorado Plateau- Abajo, LaSal, Henry, and Chuska Mts., and Boulder Mountain of the Aquarius Plateau-and analyzed using traditional phylogenetic approaches (parsimony and likelihood) as well as nested clade analysis. Results support previous documentation of a major east-west phylogeographic break occurring between populations southeast of the Colorado River (eastern Arizona, Colorado, Wyoming and New Mexico) and all other western populations, which …
Date: May 2004
Creator: Carr, Carla B.
System: The UNT Digital Library

Social Skills Intervention for Students with Emotional/Behavioral Disorders Aged Six through Twelve Years: A Combination of a Literature-Based Curriculum and Telecommunications

Access: Use of this item is restricted to the UNT Community
Researchers have noted that by providing formal and informal social skills training (SST), the school can become a potential optimal setting that fosters the development of social competence in students with behavioral problems. Indeed, learning to get along with people is one of the most important skills that we can teach students. In order to maximize its effectiveness, SST must be motivating and personally relevant enough for students to want to use the skills. In addition, it must provide opportunities for learned skills to be practiced under varying conditions and in as close to natural situations as possible in order to enhance the transfer of training. The purpose of the study was to investigate the social competence of students aged from six to twelve, diagnosed with emotional/behavioral disorders (E/BD) in a public self-contained school setting, and to increase the students' social competence by using a literature-based method that employs multiage grouping, impersonation, and telecommunications. By providing intensive, literature-based training in a multiage classroom, the SST gave students opportunities to practice skills in a natural, real-life environment and, therefore, increased the likelihood of generalizing these skills in other settings. The employment of impersonation and telecommunications also enhanced students' acquisition of social …
Date: May 2004
Creator: Chen, Kaili
System: The UNT Digital Library

Reconsidering the Lament: Form, Content, and Genre in Italian Chamber Recitative Laments: 1600-1640

Access: Use of this item is restricted to the UNT Community
Scholars have considered Italian chamber recitative laments only a transitional phenomenon between madrigal laments and laments organized on the descending tetrachord bass. However, the recitative lament is distinguished from them by its characteristic attitude toward the relationship between music and text. Composer of Italian chamber recitative laments attempted to express more subtle, refined and sometimes complicated emotion in their music. For that purpose, they intentionally created discrepancies between text and music. Sometimes they even destroy the original structure of text in order to clearly deliver the composer's own voice. The basic syntactic structure is deconstructed and reconstructed along with their reading and according to their intention. The discrepancy between text and music is, however, expectable and natural phenomena since text cannot be completely translated or transformed to music and vice versa. The composers of Italian chamber recitative laments utilized their innate heterogeneity between two materials (music and text) as a metaphor that represents the semantic essence of the genre, the conflict. In this context, Italian chamber recitative laments were a real embodiment of the so-called seconda prattica and through the study of them, finally, we more fully able to understand how the spirit of late Renaissance flourished in Italy in …
Date: December 2004
Creator: Chung, Kyung-Young
System: The UNT Digital Library

Narcissistic traits and parenting style: A closer look at maladaptive parenting through parent-child observations, parent self-report, and child self-report.

Access: Use of this item is restricted to the UNT Community
The thrust of this paper was two-fold, 1) to confirm a 2-factor model of narcissism in women, and 2) to examine the relationship between narcissistic traits in mothers and several variables associated with parenting efficacy. Participants included 193 mother-child dyads. A 2-factor model of narcissism was confirmed in the present sample of mothers, suggesting that narcissistic traits in women may be manifested in distinct Overt and Covert forms. Contrary to expectations, Covert Narcissistic traits in mothers did not significantly correlate with observed parenting behaviors on the PCIA, including Positive Personal Comments (PPC) towards children, Negative Personal Comments (NPC), and Parental Nurturance. However, children's self-reported maternal rejection on the C-PARQ correlated positively with Covert Narcissistic traits in mothers, as did mother's self-reported dysfunctional parenting attitudes on the AAPI-2. Narcissistic traits in mothers correlated most strongly with risk of child physical abuse on the CAPI (r = .70). Results are also presented for the Overt Narcissism factor, which proved to be less stable as a factor. Overall, results emphasize the need for a more comprehensive understanding of narcissism for women, given its potential Implications for children's healthy development and parenting interventions.
Date: August 2004
Creator: Collins, Michelle
System: The UNT Digital Library

Bioavailability and toxicity of 2,4,6-trinitrotoluene in sediment.

Access: Use of this item is restricted to the UNT Community
TNT (2,4,6-trinitrotoluene) is a persistent contaminant at many military installations and poses a threat to aquatic ecosystems. Data from environmental fate and toxicity studies with TNT revealed that sediment toxicity test procedures required modification to accurately assess sediment TNT toxicity. Key modifications included aging TNT-spiked sediments 8-14 d, basing lethal dose on measured sediment concentrations of the molar sum of TNT and its main nitroaromatic (NA) transformation products (SNA), basing sublethal dose on average sediment SNA concentrations obtained from integration of sediment SNA transformation models, avoiding overlying water exchanges, and minimizing toxicity test durations. Solid phase microextraction fibers (SPMEs) were investigated as a biomimetic chemical measure of toxicity and bioavailability. Both organism and SPME concentrations provided measures of lethal dose independent of exposure scenario (TNT-spiked sediment or TNT-spiked water) for Tubifex tubifex. Among all benthic organisms tested (Chironomus tentans, Ceriodaphnia dubia, T. tubifex) and matrixes, median lethal dose (LC50) estimates based on SPME and organism concentrations ranged from 12.6 to 55.3 mmol SNA/ml polyacrylate and 83.4 to 172.3 nmol SNA/g tissue, ww, respectively. For Tubifex, LC50s (95% CI) based on SNA concentrations in sediment and SPMEs were 223 (209-238) nmol SNA/g, dw and 27.8 (26.0-29.8) mmol SNA/ml, respectively. Reproductive effects …
Date: May 2004
Creator: Conder, Jason M.
System: The UNT Digital Library

An investigation of success metrics for the design of e-commerce Web sites.

Access: Use of this item is restricted to the UNT Community
The majority of Web site design literature mainly concentrates on the technical and functional aspects of Web site design. There is a definite lack of literature, in the IS field, that concentrates on the visual and aesthetic aspects of Web design. Preliminary research into the relationship between visual design and successful electronic commerce Web sites was conducted. The emphasis of this research was to answer the following three questions. What role do visual design elements play in the success of electronic commerce Web sites? What role do visual design principles play in the success of electronic commerce Web sites? What role do the typographic variables of visual design play in the success of electronic commerce Web sites? Forty-three undergraduate students enrolled in an introductory level MIS course used a Likert-style survey instrument to evaluate aesthetic aspects of 501 electronic commerce Web pages. The instrument employed a taxonomy of visual design that focused on three dimensions: design elements, design principles, and typography. The data collected were correlated against Internet usage success metrics data provided by Nielsen/NetRatings. Results indicate that 22 of the 135 tested relationships were statistically significant. Positive relationships existed between four different aesthetic dimensions and one single success measure. …
Date: May 2004
Creator: Cutshall, Robert C.
System: The UNT Digital Library

Application of Cultured Neuronal Networks for Use as Biological Sensors in Water Toxicology and Lipid Signaling.

Access: Use of this item is restricted to the UNT Community
This dissertation research explored the capabilities of neuronal networks grown on substrate integrated microelectrode arrays in vitro to be applied to toxicological research and lipid signaling. Chapter 1 details the effects of chlorine on neuronal network spontaneous electrical activity and pharmacological sensitivity. This study demonstrates that neuronal networks can maintain baseline spontaneous activity, and respond normally to pharmacological manipulations in the present of three times the chlorine present in drinking water. The findings suggest that neuronal networks may be used as biological sensors to monitor the quality of water and the presence of novel toxicants that cannot be detected by conventional sensors. Chapter 2 details the neuromodulatory effects of N-acylethanolamides (NAEs) on the spontaneous electrical activity of neuronal networks. NAEs are a group of lipids that can mimic the effects of marijuana and can be derived from a variety of plant sources including soy lecithin. The most prominent NAEs in soy lecithin, palmitoylethanolamide (PEA) and linoleoylethanolamide (LEA), were tested individually and were found to significantly inhibit neuronal spiking and bursting activity. These effects were potentiated by a mixture of NAEs as found in a HPLC enriched fraction from soy lecithin. Cannabinoid receptor-1 (CB1-R) antagonists and other cannabinoid pathway modulators indicated …
Date: August 2004
Creator: Dian, Emese Emöke
System: The UNT Digital Library

Modeling wild type and mutant glutathione synthetase.

Access: Use of this item is restricted to the UNT Community
Glutathione syntethase (GS) is an enzyme that belongs to the ATP-grasp superfamily and catalyzes the second step in the biosynthesis of glutathione. GS has been purified and sequenced from a variety of biological sources; still, its exact mechanism is not fully understood. Four highly conserved residues were identified in the binding site of human GS. Additionally, the G-loop residues that close the active site during catalysis were found to be conserved. Since these residues are important for catalysis, their function was studied computationally by site-directed mutagenesis. Starting from the reported crystal structure of human GS, different conformations for the wild type and mutants were obtained using molecular dynamics technique. The key interactions between residues and ligands were detected and found to be essential for enzyme activity.
Date: August 2004
Creator: Dinescu, Adriana
System: The UNT Digital Library

Functional analysis and elimination of SIB in an olive baboon (Papio hamadryas anubis).

Access: Use of this item is restricted to the UNT Community
Self injurious behavior (SIB), such as self-biting and head-banging, has been reported to occur in approximately 10% of captive, individually housed primates (Novak, Kinsely, Jorgensen, and Hazen, 1998). Accounts of the causes of SIB range from environmental to physiological. However, to date, no researchers have investigated the possible influence of social consequences, delivered by handlers and keepers, in the maintenance of SIB. There is only one research report showing that self-injury can be shaped in primates by the manipulation of food as a reinforcing consequence for the animal's behavior. The current study investigated the effects of social contact as potentially reinforcing consequences for the SIB displayed by an olive baboon (Papio hamadryas anubis). Results indicated that the behavior was maintained by attention from humans. As treatment, reinforcement was arranged for an appropriate alternative attention-getting behavior, resulting in increases in the appropriate alternative behavior and decreases in SIB.
Date: August 2004
Creator: Dorey, Nicole R.
System: The UNT Digital Library

The significance of supportive structure in improving student achievement in knowledge of the history of the Christian church in a Kenyan Bible college.

Access: Use of this item is restricted to the UNT Community
The problem of this study was to determine whether Kenyan Bible college students who receive instruction using a modified (highly structured) mastery learning model will demonstrate greater achievement in knowledge of Christian Church history as compared to Kenyan Bible college students who receive instruction using a traditional (minimally structured) non-mastery learning model. The subjects were 17 second-year Kenyan Bible college students enrolled in a course on Christian Church history, and they were randomly assigned to the two treatment conditions. The researcher served as instructor for both groups. The experimental group used a textbook, detailed syllabus, 200 page study guide (featuring an advance organizer to provide an ideational scaffolding), and a lesson-development feature (providing an enabling objective, congruent questions, and informative feedback for each lesson segment). The control group used a textbook and a less-detailed syllabus. Both groups shared the same classroom lectures, class discussions, required assignments, examinations, and review of examination items. Five tests of Christian church history were administered, including a pretest, three unit tests, and a comprehensive course examination. Test data were analyzed using a 2 x 5 (treatment x testing occasion) repeated measures analysis of variance (RM ANOVA). The percentage of students performing at mastery level (80% …
Date: May 2004
Creator: Duncan, David D.
System: The UNT Digital Library

First-term Air Force medical service corps officers: Relationship between MBTI® and initial occupational placement to predict job satisfaction.

Access: Use of this item is restricted to the UNT Community
The purpose of this study was to determine whether a relationship exists between the Myers-Briggs Type Indicator® (MBTI®) of first-term Air Force medical service corps (MSC) officers and their initial occupational placement matches (OCUPLACE MATCH), and, if so, whether this could it predict job satisfaction. The population consisted of 116 first-term Air Force MSC officers already assigned and working at their initial occupational placement. Statistical Package for the Social Sciences (SPSS®) computer software program was used for the statistical computation. Several techniques were used, including, frequency distribution, the Pearson product-moment correlation coefficient, and regression analyses, among others. Results showed a statistical significant correlation between the MBTI type of the first-term MSC officer matches and their initial occupational placement (OCUPLACE MATCH, r = .440, p < .01). Furthermore, results of a regression analysis showed no statistical significance for predication on job satisfaction (r = 492, F = .887, p < .05). Based on this study, the Air Force Personnel Center can match first-term MSC officers' personality type to an initial occupation placement; however, based on the second part of the hypothesis, prediction of job satisfaction may not be yield on less other aspects of the group are considered such as time …
Date: August 2004
Creator: Edie-Korleski, Montserrat P.
System: The UNT Digital Library

Claremont Connections

Access: Use of this item is restricted to the UNT Community
Claremont Connections is a collection of fictional short stories about the relationships between the generations of women in one family and their friends.
Date: August 2004
Creator: Elerson, Crystal L.
System: The UNT Digital Library

Random growth of interfaces: Statistical analysis of single columns and detection of critical events.

Access: Use of this item is restricted to the UNT Community
The dynamics of growth and formation of surfaces and interfaces is becoming very important for the understanding of the origin and the behavior of a wide range of natural and industrial dynamical processes. The first part of the paper is focused on the interesting field of the random growth of surfaces and interfaces, which finds application in physics, geology, biology, economics, and engineering among others. In this part it is studied the random growth of surfaces from within the perspective of a single column, namely, the fluctuation of the column height around the mean value, which is depicted as being subordinated to a standard fluctuation-dissipation process with friction g. It is argued that the main properties of Kardar-Parisi-Zhang theory are derived by identifying the distribution of return times to y(0) = 0, which is a truncated inverse power law, with the distribution of subordination times. The agreement of the theoretical prediction with the numerical treatment of the model of ballistic deposition is remarkably good, in spite of the finite size effects affecting this model. The second part of the paper deals with the efficiency of the diffusion entropy analysis (DEA) when applied to the studies of stromatolites. In this case …
Date: August 2004
Creator: Failla, Roberto
System: The UNT Digital Library