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Application Of The Empirical Likelihood Method In Proportional Hazards Model, Bin He Jan 2006

Application Of The Empirical Likelihood Method In Proportional Hazards Model, Bin He

Electronic Theses and Dissertations

In survival analysis, proportional hazards model is the most commonly used and the Cox model is the most popular. These models are developed to facilitate statistical analysis frequently encountered in medical research or reliability studies. In analyzing real data sets, checking the validity of the model assumptions is a key component. However, the presence of complicated types of censoring such as double censoring and partly interval-censoring in survival data makes model assessment difficult, and the existing tests for goodness-of-fit do not have direct extension to these complicated types of censored data. In this work, we use empirical likelihood (Owen, 1988) …

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Direct Nonlinear Optics Measurements Of Raman Gain In Bulk Glasses And Estimates Of Fiber Performance, Robert Stegeman Jan 2006

Direct Nonlinear Optics Measurements Of Raman Gain In Bulk Glasses And Estimates Of Fiber Performance, Robert Stegeman

Electronic Theses and Dissertations

The need for more bandwidth in communications has stimulated the search for new fiberizable materials with properties superior to fused silica which is the current state-of-the-art. One of the key properties is Raman gain by which a pump beam amplifies a signal beam of longer wavelength. An apparatus capable of directly measuring the spectral dependence and absolute magnitude of the material Raman gain coefficient using nonlinear optics techniques has been built. Using radiation from a 1064 nm Nd:YAG laser as the pump and from a tunable Optical Parametric Generator and Amplifier as the signal, the Raman gain spectrum was measured …

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The Effects Of Gender In Elementary Science Groups, Melissa Parks Jan 2006

The Effects Of Gender In Elementary Science Groups, Melissa Parks

Electronic Theses and Dissertations

This action research study investigated the effects of gender on same and mixed gender elementary school science groups. Qualitative data for this study was collected using surveys, student focus groups, student journals, and teacher-researcher field notes and observations. Students in this study were eager to participate in science groups and demonstrated a positive attitude toward the study of science. Results also showed the types of interactions between boys and girls varied and those interactions affected their science attitude and participation. Recommendations were made for continued research to examine the long-term effects of gender groupings in the elementary science classroom.

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Antenna-Coupled Infrared And Millimeter-Wave Detectors: Fabrication, Measurement And Optimization, Charles Middleton Jan 2006

Antenna-Coupled Infrared And Millimeter-Wave Detectors: Fabrication, Measurement And Optimization, Charles Middleton

Electronic Theses and Dissertations

Antenna-coupled detectors provide uncooled, cost-effective solutions for infrared and millimeter-wave imaging. This work describes the design, fabrication, measurement, and optimization of several types of antenna-coupled detectors for LWIR (8 - 12 µm) and 94 GHz radiation. Two types of millimeter-wave antenna-coupled detectors were fabricated and tested: a slot antenna coupled to a bolometer, and a patch antenna coupled to a SiC Schottky diode. Electromagnetic modeling of the antennas helped guide the design of antennas with better impedance matching to the detectors. Schottky diodes are discussed as detectors for millimeter-wave and infrared radiation, with the goal of increasing the cutoff frequency …

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Integrated Inp Photonic Switches, Daniel May-Arrioja Jan 2006

Integrated Inp Photonic Switches, Daniel May-Arrioja

Electronic Theses and Dissertations

Photonic switches are becoming key components in advanced optical networks because of the large variety of applications that they can perform. One of the key advantages of photonic switches is that they redirect or convert light without having to make any optical to electronic conversions and vice versa, thus allowing networking functions to be lowered into the optical layer. InP-based switches are particularly attractive because of their small size, low electrical power consumption, and compatibility with integration of laser sources, photo-detectors, and electronic components. In this dissertation the development of integrated InP photonic switches using an area-selective zinc diffusion process …

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The Effect Of Different Presentation Formats Of Hypertext Annotations On Cognitive Load, Learning And Learner Control, Yuanming Yao Jan 2006

The Effect Of Different Presentation Formats Of Hypertext Annotations On Cognitive Load, Learning And Learner Control, Yuanming Yao

Electronic Theses and Dissertations

This dissertation study was intended to verify whether the positive effects of the roll-over annotation presentation format on reducing cognitive load and enhancing vocabulary and comprehension of 5th-grade children (Morrison, 2004) can be extended to college students' learning from a web-delivered text. In order to answer this research question, relevant constructs, such as cognitive load, learner control and learning, have been examined in this experimental study of 149 undergraduate students in a state university at College of Education. No single effect of annotation presentation format on cognitive load was found, but an interaction effect on cognitive load was revealed between …

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Teacher Retention In Brevard County, Florida K-12 Schools, Kenneth Winn Jan 2006

Teacher Retention In Brevard County, Florida K-12 Schools, Kenneth Winn

Electronic Theses and Dissertations

This descriptive study was designed to determine the extent to which selected self-reported practical and professional factors of teaching influenced teacher job satisfaction and retention within the K-12 public education system. The population of the study was 1321 certified teachers from a large Central Florida school district. The researcher developed the survey instrument based on the constructs of teaching known for motivating teachers to remain within the public school setting (Brunetti, 2001; Farkas, Johnson, & Folena, 2005). The researcher's survey was based on the studies of Perie (1997), Brunetti (2001), and Gary (2002). The researcher personally distributed 1321 surveys, respondent …

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A Comparison Of Ordinary Least Squares, Weighted Least Squares, And Other Procedures When Testing For The Equality Of Regression, Patrick J. Rosopa Jan 2006

A Comparison Of Ordinary Least Squares, Weighted Least Squares, And Other Procedures When Testing For The Equality Of Regression, Patrick J. Rosopa

Electronic Theses and Dissertations

When testing for the equality of regression slopes based on ordinary least squares (OLS) estimation, extant research has shown that the standard F performs poorly when the critical assumption of homoscedasticity is violated, resulting in increased Type I error rates and reduced statistical power (Box, 1954; DeShon & Alexander, 1996; Wilcox, 1997). Overton (2001) recommended weighted least squares estimation, demonstrating that it outperformed OLS and performed comparably to various statistical approximations. However, Overton's method was limited to two groups. In this study, a generalization of Overton's method is described. Then, using a Monte Carlo simulation, its performance was compared to …

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The Analysis Of The Relationship Between Learning Styles And The Learners' Knowledge Acquisition And Reactions Through The Online Case Study, Rui Zeng Jan 2006

The Analysis Of The Relationship Between Learning Styles And The Learners' Knowledge Acquisition And Reactions Through The Online Case Study, Rui Zeng

Electronic Theses and Dissertations

The purpose of this study was to examine the relationship between learning styles and student performance on a pre and post test, using an online case study, while also documenting their reactions to the case study. The case studies used in this research contained different storylines that showed multiple perspectives of case scenarios, giving students more choices to see what may happen in real school situations. Working with undergraduate students (N = 138) from the College of Education at a southeastern university, the researcher examined how students learned and responded to an online case study relative to their learning styles. …

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Effect Of Germanium Doping On Erbium Sensitization In The Erbium Doped Silicon Rich Silica Material System, Forrest Ruhge Jan 2006

Effect Of Germanium Doping On Erbium Sensitization In The Erbium Doped Silicon Rich Silica Material System, Forrest Ruhge

Electronic Theses and Dissertations

The continued size reduction in electronic integrated circuits has lead to a demand for on-chip high-bandwidth and low loss communication channels. Optical interconnects are considered an essential addition to the silicon electronics platform. A major challenge in the field of integrated Si photonics is the development of cost effective silicon compatible light sources. This thesis investigates the sensitization of group IV doped silica films emitting at 1.535μm for applications as silicon compatible light sources. Thin erbium-doped silica films containing excess silicon and germanium were deposited using a multi-gun sputter system. The composition of the deposited materials was verified by Rutherford …

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External Cavity Multiwavelength Semiconductor Mode-Locked Laser Gain Dynamics, Luis Archundia-Berra Jan 2006

External Cavity Multiwavelength Semiconductor Mode-Locked Laser Gain Dynamics, Luis Archundia-Berra

Electronic Theses and Dissertations

External cavity semiconductor mode-locked lasers can produce pulses of a few picoseconds. The pulses from these lasers are inherently chirped with a predominant linear chirp component that can be compensated resulting in sub-picosecond pulses. External cavity semiconductor mode-locked lasers can be configured as multiwavelength pulse sources and are good candidates for time and wavelength division multiplexing applications. The gain medium in external cavity semiconductor mode-locked lasers is a semiconductor optical amplifier (SOA), and passive and hybrid mode-locked operation are achieved by the introduction of a saturable absorber (SA) in the laser cavity. Pump-probe techniques were used to measure the intracavity …

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Police Organizational Performance In The State Of Florida:Confirmatory Analysis Of The Relationship Of The Environment And Design Structure To Performance, Jeffrey Goltz Jan 2006

Police Organizational Performance In The State Of Florida:Confirmatory Analysis Of The Relationship Of The Environment And Design Structure To Performance, Jeffrey Goltz

Electronic Theses and Dissertations

To date, police organizations have not been rigorously analyzed by organizational scholars and most analysis of these organizations has been captured through a single construct. The purpose of this study is to develop confirmatory police organizational analysis by validating a multi-dimensional conceptual framework that explains the relationships among three constructs: environmental constraints, the design structures of police organizations, and organizational performance indicators. The modeling is deeply rooted in contingency theory, and the influence of isomorphism and institutional theory on the covariance structure model are investigated. One hundred and thirteen local police organizations from the State of Florida are included in …

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Three-Photon Absorption Process In Organic Dyes Enhanced By Surface Plasmon Resonance, Ion Cohanoschi Jan 2006

Three-Photon Absorption Process In Organic Dyes Enhanced By Surface Plasmon Resonance, Ion Cohanoschi

Electronic Theses and Dissertations

Multi-photon absorption processes have received significant attention from the scientific community during the last decade, mainly because of their potential applications in optical limiting, data storage and biomedical fields. Perhaps, one of the most investigated processes studied so far has been two-photon absorption (2PA). These investigations have resulted in successful applications in all the fields mentioned above. However, 2PA present some limitations in the biomedical field when pumping at typical 2PA wavelengths. In order to overcome these limitations, three-photon absorption (3PA) process has been proposed. However, 3PA in organic molecules has a disadvantage, typical values of σ3' are small (10-81 …

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Effects Of Atmospheric Turbulence On The Propagation Of Flattened Gaussian Optical Beams, Doris Cowan Jan 2006

Effects Of Atmospheric Turbulence On The Propagation Of Flattened Gaussian Optical Beams, Doris Cowan

Electronic Theses and Dissertations

In an attempt to mitigate the effects of the atmosphere on the coherence of an optical (laser) beam, interest has recently been shown in changing the beam shape to determine if a different power distribution at the transmitter will reduce the effects of the random fluctuations in the refractive index. Here, a model is developed for the field of a flattened Gaussian beam as it propagates through atmospheric turbulence, and the resulting effects upon the scintillation of the beam and upon beam wander are determined. A comparison of these results is made with the like effects on a standard TEM00 …

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High Birefringence And Low Viscosity Liquid Crystals, Chien-Hui Wen Jan 2006

High Birefringence And Low Viscosity Liquid Crystals, Chien-Hui Wen

Electronic Theses and Dissertations

In this dissertation, liquid crystal (LC) materials and devices are investigated in order to meet the challenges for photonics and displays applications. We have studied three kinds of liquid crystal materials: positive dielectric anisotropic LCs, negative dielectric anisotropic LCs, and dual- frequency LCs. For the positive dielectric anisotropic LCs, we have developed some high birefringence isothiocyanato tolane LC compounds with birefringence ~0.4, and super high birefringence isothiocyanato biphenyl-bistolane LC compounds with birefringence as high as ~0.7. Moreover, we have studied the photostability of several high birefringence LC compounds, mixtures, and LC alignment layers in order to determine the failure mechanism …

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Development And Evaluation Of A Single-Session Expectancy Challenge Intervention To Reduce Alcohol Use Among Heavy Drinking College Students, Hoyee Lau Jan 2006

Development And Evaluation Of A Single-Session Expectancy Challenge Intervention To Reduce Alcohol Use Among Heavy Drinking College Students, Hoyee Lau

Electronic Theses and Dissertations

While overall rates of college student drinking have declined slightly since 1980, extreme forms of drinking are escalating. A comprehensive review of all aspects of alcohol use among college students completed by a panel of scientists and college presidents concluded that very few approaches for dealing with student drinking can be considered empirically validated, and they strongly encouraged additional efforts to develop and validate effective strategies. Expectancy challenge approaches designed to reduce risky drinking through changing key expectancies have been identified as one of the few validated strategies, but this approach has not been developed into a format that is …

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Near-Infrared Observations Of Comet-Asteroid Transition Objects, Julie Elaine Ziffer Jan 2006

Near-Infrared Observations Of Comet-Asteroid Transition Objects, Julie Elaine Ziffer

Electronic Theses and Dissertations

The primary objective of this research is to characterize the surface composition of five comet-asteroid transition objects via near-infrared spectroscopy. The five targets include two asteroids with Tisserand invariants lower than 3.0 (1373 Cincinnati and 2906 Caltech), one asteroid that is likely an extinct comet (944 Hidalgo), one intermittent activity comet (162P/Siding Spring), and one nearly dormant comet (28P/Neujmin1). Previous research regarding cometary end states and dynamical and physical properties of comets and asteroids provides the foundation for this work. Focusing primarily on the 1-2.5 µm spectral region of the five target objects, this project specifically searches for mineral species …

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On The Use Of Gaussian Filter Functions For Adaptive Optics, Merfit Assad Jan 2006

On The Use Of Gaussian Filter Functions For Adaptive Optics, Merfit Assad

Electronic Theses and Dissertations

For adaptive optic systems, the use of aperture filter functions calculated using various Zernike modes can be useful in removing lower-order aberrations caused by atmospheric turbulence. Traditionally, these filter functions are calculated using the step function depicting a hard aperture that introduces integrals that are sometimes difficult to integrate and must be done numerically. The Gaussian method can be used in place of the conventional method for calculating the aperture filter functions. Evaluation of the Gaussian approximation for modeling a finite receiver aperture can be made by comparison of reduction in phase variance with results achieved using the conventional method. …

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Analytical Potential Of Polymerized Liposomes Bound To Lanthanide Ions For Qualitative And Quantitative Analysis Of Proteins, Marina Santos Jan 2006

Analytical Potential Of Polymerized Liposomes Bound To Lanthanide Ions For Qualitative And Quantitative Analysis Of Proteins, Marina Santos

Electronic Theses and Dissertations

One of the intriguing features of biological systems is the prevalence of highly selective and often very strong interactions among different cellular components. Such interactions play a variety of organizational, mechanical, and physiological roles at the cellular and organism levels. Antigen-antibody complexes are representative examples of highly selective and potent interactions involving proteins. The marked specificity of protein-antibody complexes have led to a wide range of applications in cellular and molecular biology related research. They have become an integral research tool in the present genomic and proteomic era. Unfortunately, the production of selective tools based on antigen-antibody interactions requires cumbersome …

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Design And Optimization Of Nano-Optical Elements By Coupling Fabrication To Optical Behavior, Raymond Rumpf Jan 2006

Design And Optimization Of Nano-Optical Elements By Coupling Fabrication To Optical Behavior, Raymond Rumpf

Electronic Theses and Dissertations

Photonic crystals and nanophotonics have received a great deal of attention over the last decade, largely due to improved numerical modeling and advances in fabrication technologies. To this day, fabrication and optical behavior remain decoupled during the design phase and numerous assumptions are made about "perfect" geometry. As research moves from theory to real devices, predicting device behavior based on realistic geometry becomes critical. In this dissertation, a set of numerical tools was developed to model micro and nano fabrication processes. They were combined with equally capable tools to model optical performance of the simulated structures. Using these tools, it …

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Predicting Surface Scatter Using A Linear Systems Formulation Of Non-Paraxial Scalar Diffraction, Andrey Krywonos Jan 2006

Predicting Surface Scatter Using A Linear Systems Formulation Of Non-Paraxial Scalar Diffraction, Andrey Krywonos

Electronic Theses and Dissertations

Scattering effects from rough surfaces are non-paraxial diffraction phenomena resulting from random phase variations in the reflected wavefront. The ability to predict these effects is important in a variety of applications including x-ray and EUV imaging, the design of stray light rejection systems, and reflection modeling for rendering realistic scenes and animations of physical objects in computer graphics. Rayleigh-Rice (small perturbation method) and Beckmann-Kirchoff (Kirchhoff approximation) theories are commonly used to predict surface scatter effects. In addition, Harvey and Shack developed a linear systems formulation of surface scatter phenomena in which the scattering behavior is characterized by a surface transfer …

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Probing Random Media With Singular Waves, Chaim Schwartz Jan 2006

Probing Random Media With Singular Waves, Chaim Schwartz

Electronic Theses and Dissertations

In recent years a resurgence of interest in wave singularities (of which optical vortices are a prominent example), light angular momentum and the relations between them has occurred. Many applications in various areas of linear and non-linear optics have been based on studying effects related to angular momentum and optical vortices. This dissertation examines the use of such wave singularities for studying the light propagation in highly inhomogeneous media and the relationship to angular momentum transfer. Angular momentum carried by light can be, in many cases, divided in two terms. The first one relates to the polarization of light and …

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Middle School Mathematics Teacher Certification, Degree Level, And Experience, And The Effects On Teacher Attrition And Student Mathematics Achievement In A Large Urban District, Bonnie Swan Jan 2006

Middle School Mathematics Teacher Certification, Degree Level, And Experience, And The Effects On Teacher Attrition And Student Mathematics Achievement In A Large Urban District, Bonnie Swan

Electronic Theses and Dissertations

The purpose of this study was to examine the backgrounds and experiences of middle school mathematics teachers that often distinguish "quality" teachers, including certification, experience, degree type, and degree level and how those demographics and others vary for different types of schools. The emphasis was on profiling teachers in a large urban district by describing their basic features and distributions, as well as how middle school mathematics teachers, according to those differences, relate to student mathematics achievement, teacher attrition and teacher mobility. Student achievement was measured by test results from the Norm Reference Test-Normal Curve Equivalent (NRT-NCE) mathematics portion of …

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Quantitative High-Angle Annular Dark Field Scanning Transmission To Electron Microscopy For Materials Science, Rumyana Petrova Jan 2006

Quantitative High-Angle Annular Dark Field Scanning Transmission To Electron Microscopy For Materials Science, Rumyana Petrova

Electronic Theses and Dissertations

Scanning transmission electron microscopy (STEM) has been widely used for characterization of materials; to identify micro- and nano-structures within a sample and to analyze crystal and defect structures. High-angle annular dark field (HAADF) STEM imaging using atomic number (Z) contrast has proven capable of resolving atomic structures with better than 2 A lateral resolution. In this work, the HAADF STEM imaging mode is used in combination with multislice simulations. This combination is applied to the investigation of the temperature dependence of the intensity collected by the HAADF detector in silicon, and to convergent beam electron diffraction (CBED) to measure the …

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Portraying Pointillism: An Actress's Journey Through Pointillism To Define The Role Of Dot In Sondheim And Lapine's Musical Sunday In The Park With George, Chris Staffel Jan 2006

Portraying Pointillism: An Actress's Journey Through Pointillism To Define The Role Of Dot In Sondheim And Lapine's Musical Sunday In The Park With George, Chris Staffel

Electronic Theses and Dissertations

Upon receiving a role, an actor must research the major themes, concepts, and relationships associated with the play, its collaborators, and the character they are to portray. Only by layering this combination of research and analysis to the rehearsal process and performances in a detailed format can an actor cohesively transform the learned knowledge from the performer's training and research to a finished product on stage. Many forms of art are created using a similar process. This thesis will explore the similarities between the Post-Impressionist technique of pointillism and the actor's process in developing a role. Upon observing the basic …

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Central Florida Future, Vol. 38 No. 33, December 19, 2005 Dec 2005

Central Florida Future, Vol. 38 No. 33, December 19, 2005

Central Florida Future

The time flies by: Success in 2005 only makes 2006 seem much more exciting; Alumni mourn loss of dear friend; Early decision on rise: College applicants make quick choices, experts believe it could be bad; Completion of FDLE investigation leads to arrest for battering officer in Jenkins melee.

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Central Florida Future, Vol. 38 No. 21, October 27, 2005 Oct 2005

Central Florida Future, Vol. 38 No. 21, October 27, 2005

Central Florida Future

They're giving out some good citations: Organizer claims Good Sport season full of responsibility; Activists take to the clothesline for victims; Battle for north and south: Residents protesters still aim for change of stadium location; 2005 UCF Breast Cancer Update focuses on true stories of survival; Women physicists honored for contributions: Women's Research Center also handed out two grants.

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Central Florida Future, Vol. 38 No. 18, October 17, 2005 Oct 2005

Central Florida Future, Vol. 38 No. 18, October 17, 2005

Central Florida Future

Arts and Sciences to announce split: Growing deficit causing college to break into two new colleges come January; Traveling fans enjoy flavor of the South: Football roadtrip results in love for 'best barbecue ever'; Senate off to cultural start keeps pro tempore; Newly elected get lesson on policies: Annual Senate retreat teaches veterans rookies rules and jobs.

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Central Florida Future, Vol. 38 No. 15, October 6, 2005 Oct 2005

Central Florida Future, Vol. 38 No. 15, October 6, 2005

Central Florida Future

Gunfire ends in loitering prowling charges: Residents petition for more lighting security wall after second incident in a year; Taking action: President Hitt approves task force recommendations; Run-off brings Whitaker to Senate: Only 100 voted SGA Senate retreat the next step in annual orientation process; New program still focused on rewarding good behavior; Greek alumnus collects for fund: Kevan Stone reaches out to students in Jenkins' name.

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The Learning Marketspace, October 2005, Bob Heterick, Carol Twigg Oct 2005

The Learning Marketspace, October 2005, Bob Heterick, Carol Twigg

The Learning MarketSpace (4/03 - 4/14)

No abstract provided.

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