Digital Commons Network^™

Leading Transformational Change In A Large Urban School District, Leslie Jean Brinks

UNLV Theses, Dissertations, Professional Papers, and Capstones

This abstract reflects the findings of the understanding of the skills necessary to lead transformative change in a non-affluent neighborhood in a large urban district. Current research and understandings of transformative leadership has been limited to traits and organizational concepts rather than the work associated with transforming schools. Studies seldom addressed if leaders even valued the actions central to transformative work or if they have the capacity and expertise to do the task. The purpose of this study was to understand the kinds of knowledge, skills, and dispositions that support what is viewed as transformative leading. Additionally the inquiry probed …

Adaptive Local And Global Synchronization And Phase Control Of Inferior Olive Neurons (Ions), Srujan Kumar Chalike

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clusters of inferior olive neurons (IONs) in the olive-cerebellar system play an important role in providing synchronized motor control signals for the activation of large number of muscles. However, the dynamics of IONs are highly nonlinear and the system parameters are assumed to be unknowm. The IONs evolving from arbitrary initial conditions are not synchronized. However the application of IONs for control of BAUV's requires that IONs oscillate in unison. The objective is to design control laws such that the controlled ION tracks the trajectories of the reference ION. The two control laws are derived based on tuning functions adaptive …

Nitrite Oxidation In Geothermal Springs: Evidence Of An Upper Temperature Limit For Thermophilic Nitrite-Oxidizing Bacteria Of 60 - 65 °C, Tara Edwards

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite growing evidence of the importance of nitrification in terrestrial geothermal environments, little is known about nitrite oxidation in these environments. In order to further our knowledge, this study combined cultivation-dependent and -independent approaches with measurements of nitrogen speciation along the outflow channels of two Great Basin geothermal springs. Enrichment cultures were inoculated with sediment slurries from sites ranging in temperature from 42 - 87 °C at the sources and along the outflows of >15 hot springs. While attempts to enrich nitrite-oxidizing bacteria (NOB) from sites greater than or equal to 61 °C were unsuccessful, NOB were enriched from five …

Sociosexuality, Mate Preferences, And Sex Steroid Hormone Levels Among Breastfeeding Women In Manila, Michelle Escasa

UNLV Theses, Dissertations, Professional Papers, and Capstones

This project investigates the influence of lactation on female sociosexuality and mate preferences in urban Manila, a population with long-term breastfeeding, low contraceptive use, and quick return to ovulatory cycling. Physiological and evolutionary considerations suggest that lactating women face important life history allocation trade-offs between mating and parenting effort that may be manifest in their sociosexual behavior and mate preferences. Breastfeeding (n=155) and control (n=105) women were recruited to provide a saliva sample (for testosterone and estradiol analyses), complete a questionnaire, and complete a face and voice preference task to determine preferences for masculinity. Breastfeeding women reported differences in commitment …

Timeliness Of Electronic And Traditional Laboratory Reporting In Southern Nevada, 1999-2012, Jennifer Anne Lucas

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study compares the timeliness of Electronic Laboratory Reporting (ELR) with traditional reporting. ELR has been implemented in parts of the United States, and is perceived to be faster than traditional reporting. Faster reporting leads to faster public health response to prevent outbreaks, and to reduce the burden of infectious disease in communities. Nevada State law requires that diseases be reported within certain time frames. Timeliness of laboratory reporting at the Southern Nevada Health District (SNHD) from 1999-2012 was assessed by analyzing cases of four common diseases in this retrospective secondary analysis of extant data.

The difference in timeliness regarding …

Innovators And Laggards? Faculty Adoption Of Online Distance Education, Thomas Tailor Scott

UNLV Theses, Dissertations, Professional Papers, and Capstones

Over the past decade, institutions of higher education have seen enrollments in distance education, especially in the form of online learning, proliferate in striking numbers. In fact, some traditional colleges and universities are only experiencing real institutional growth in the areas of online learning. Even though a major push to increase the availability of distance education technology has occurred, effective adoption has not always followed suit. In hopes of speeding up the diffusion process, many colleges and universities have begun to contemplate the increased integration and institutional adoption of online learning. One of the most critical factors administrators must consider …

Molecular Forensic Science Analysis Of Nuclear Materials, Dallas Reilly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Concerns over the proliferation and instances of nuclear material in the environment have increased interest in the expansion of nuclear forensics analysis and attribution programs. A new related field, molecular forensic science (MFS) has helped meet this expansion by applying common scientific analyses to nuclear forensics scenarios. In this work, MFS was applied to three scenarios related to nuclear forensics analysis. In the first, uranium dioxide was synthesized and aged at four sets of static environmental conditions and studied for changes in chemical speciation. The second highlighted the importance of bulk versus particle characterizations by analyzing a heterogeneous industrially prepared …

An Infusion Of Eastern And Western Music Styles Into Art Song: Introducing Two Sets Of Art Song For Mezzo-Soprano By Chen Yi, Wen Zhang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Chinese-American composer Chen Yi has been praised as "the most internationally renowned female Asian composer of contemporary music today," and she "has in particular become a prominent figure in music circles in the United States and China." Besides her successes in writing orchestral and chamber music, Chen Yi has also written numerous vocal compositions including some art songs. This document aims to introduce two sets of Chen's art songs written for mezzo-soprano voice, Meditation and Bright Moonlight, and study the features of these compositions that represent the unique style of her music, which is influenced by Chinese folk music idioms …

Quantification Of Mixing In Microchannels, Vijaymaran Manickam

Graduate Theses, Dissertations, and Problem Reports (ETD)

Microchannels are used for delivery of two-or more fluids for multiple purposes, such as drug delivery, where good mixing is desired in a very short time (or distance). For this purpose, many design options are being proposed in the literature. For example herringbone baffles at the bottom of a rectangular channel are commonly proposed to enhance mixing in a drug delivery device. To assess the effectiveness of such devices many experiments need to be performed thus increasing the design cycle time and the cost involved. Computational fluid dynamics (CFD) can and is being used to shorten this design cycle by …

Terrorisk: The Impact Of Terrorist Attacks On Sovereign Bond Yield Spreads Of Targeted Countries, Slava Rar

Business/Business Administration

This study estimates the effects of terrorism incidents on a nation’s borrowing costs. An event study approach is used to evaluate changes in sovereign-bond yield spreads after terrorist attacks occur. Prior research is not in consensus on whether the effect of terrorism on bond markets is significant, and no study shows why certain bond indices may rise while others may fall after a terrorist attack. This study does not find statistical significance, which suggests that the effect of an attack may depend on the targeted country. For terrorist researchers, this study is one step toward answering whether terrorists can manipulate …

Parkinson Disease And Rehabilitation Administration And Services, Deanna Booker

Research Papers

No abstract provided.

Production Of Poly-?-Glutamic Acid By Bacillus Licheniformis: Synthesis And Characterization, N. Konglom, C. Chuensangjun, C. Pechyen, S. Sirisansaneeyakul

Journal of Metals, Materials and Minerals

Poly-?-glutamic acid (?-PGA), one type of amino acid polymers, consists of D-and L-glutamic acids linked with amide bonding between ?-amino and ?-carboxylic acids. Naturally, ?-PGA could be biodegradable polymer and water-solubleapplied in various industries such as food, cosmetics, and pharmaceutical industries. Variation of initial L-glutamic acid concentration affecting on the production of ?-PGA by fermentation of Bacillus licheniformis was studied. The batch fermentation process consists of preparing the inoculum and expanding the culture of B. licheniformis into E medium (pH 6.5) for ?-PGA production. ?-PGA was recovered by using methanol precipitation together with lyophilization. For characterization, the molecular size of …

Cetirizine Dihydrochloride Tablets Comprising Two Different Lubricants With Highly Loaded Colloidal Silicon Dioxide, P. Katewongsa, T. Phaechamud

Journal of Metals, Materials and Minerals

Recently, the fast disintegrating tablet (FDT) has started gaining popularity and acceptance as new drug delivery system. Cetirizine dihydrochloride (CD) is the selective histamine (H-1)-receptor antagonist that is demonstrated to treat the symptoms associated with seasonal and perennial allergic rhinitis which this drug nowadays was prepared in form of FDT. Lubricant typically influences on tablet disintegration time (DT) and wetting time (WT). Therefore, it is important for optimizing the lubricant amount in this dosage form. The purpose of this study was to evaluate the effect of the lubricants (magnesium stearate (Mg-st) and sodium stearyl fumarate (SSF)) on the CD tablet …

Influence Of Casting Techniques On Hardness, Tarnish Behavior And Microstructure Of Ag-Cu-Zn-Si Sterling Silver Jewelry Alloys, C. Chanmuang, W. Kongmuang, J.T.H. Pearce, T. Chairuangsri

Journal of Metals, Materials and Minerals

The effects of Zn and Si on the hardness, tarnish resistance and microstructures of experimental Ag-Cu-Zn-Si alloy were investigated by means of vickers hardness, tarnish testing, optical and scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The various compositions of 935 sterling silver alloys produced by different casting techniques, investment (lost wax) process and metal mould casting, were compared. An induction casting machine with a vacuum system was used for investment casting at 1,025C with the mould temperature at 600C whereas a LPG/oxygen single flame tip torch was used for the metal mould process. Vickers hardness of the samples …

Ballistic Performance Of Ceramic/S2-Glass Composite Armor, K. Dateraksa, K. Sujirote, R. Mccuiston, D. Atong

Journal of Metals, Materials and Minerals

Ceramic composite armor was initially developed during the Vietnam War for use as helicopter armor and personnel armor. The requirements for the armor were light weight and the capability to defeat small caliber armor piercing (AP) projectiles. Several different ceramics were developed and tested for this application. It was found that aluminum oxide (Al2O3), silicon carbide (SiC) and boron carbide (B4C) had the best combination of properties to meet the requirements. The long term goal of this research is to develop domestic knowledge, design and production capability of ceramic composite armors. In this present research, the relationship between the ballistic …

Bismuth Vanadate (Bivo4) Powder Prepared By The Sol-Gel Method, P. Pookmanee, S. Kojinok, S. Phanichphant

Journal of Metals, Materials and Minerals

Bismuth vanadate (BiVO4) powder was prepared by the sol-gel method. Bismuth nitrate and ammonium vanadate were used as the starting precursors with mole ratio of 1:1 in ethanol at 70C for 1 hour. The obtained sol was changed to the yellow gel after addition of deionized water and acetic acid. The yellow gel was dried at 100C for 48 h and calcined at 400-600C for 2 hours. The phase of BiVO4 powder was studied by X-ray diffraction (XRD). The morphology of BiVO4 powder was investigated by scanning electron microscopy (SEM). The element composition of BiVO4 powder was indicated by energy …

Effect Of Milling Method On The Particle Size Of Calcined 0.65pmn-0.35pt Powder, A. Boonruang, P. Ngernchuklin, C. Eamchotchawalit

Journal of Metals, Materials and Minerals

In this study, stoichiometric 0.65PMN-0.35PT powders have been prepared by columbite method. The perovskite single phase of PMN-PT was successfully synthesized after calcination of the mixed oxide at 900C/4hr. Due to the particle size of calcined powder has greatly effect on the electrical properties of sintered samples. Therefore, two different milling methods including high energy ball milling (HBM) and conventional ball milling (CBM) were used to grind the calcined powders. The results showed that the particle size distribution of calcined powders from HBM and CBM were 0.17 and 0.19 ?m, respectively. As a result, the relative density of the sintered …

Effect Of Zn Addition On Sol-Gel Derived Apatite/Wollastonite Glass-Ceramics Scaffolds, S. Tubsungneon Rattanachan, N. Srakaew, R. Pethnin, N. Suppakarn

Journal of Metals, Materials and Minerals

Bioactive glasses and glass-ceramics consisting of CaO-MgO-P2O5-SiO2 system have been shown to be bioactive, resorbable and to exhibit appropriate mechanical properties for bone tissue engineering applications. Bioactive glass-ceramics scaffolds consisting of zinc doped-apatite/wollastonite (AW) glassceramics were prepared by coating polyurethane foams with sol-gel derived glass gels. Density and compressive strength of the scaffolds decreased with increased in zinc contents. In vitro bioactivity of Zndoped AW glass-ceramics in a simulated body fluid (SBF) showed the formation of apatite layer on the surface within 7 days of soaking. However, increasing Zn addition increased the chemical durability of the AW glass-ceramics, resulting in …

Characterization And Drug Behavior In Shellac Wax Poloxamer Matrix Tablets Fabricated With Mold Technique, C. Choncheewa, T. Phaechamud

Journal of Metals, Materials and Minerals

Shellac wax is a waste product from shellac manufacturing process and has not been reported to be used as pharmaceutical matrix base. This study was to prepared and characterized shellac wax - poloxamer 407 matrix tablet comprising hydrophilic or hydrophobic drug which were prepared by molten technique. The ratios of poloxamer 407: shellac wax was varied and subsequently loaded with the different drug content before characterized with differential scaning calorimetry (DSC), thermogravimetric analysis (TGA) and powder x-ray diffractometry (PXRD). Drug release study was also performed for 25 mg drug loaded matrix tablet in distilled water using dissolution apparatus II at …

Role Of Aluminum Monostearate On Heat Treated-Chitosan Sponges Properties, K. Yodkhum, T. Phaechamud

Journal of Metals, Materials and Minerals

Heat treatment can be employed to modify properties such as biocompatibility and degradation rate of chitosan-based materials. However, heat treatment generally has effect on worsening of physical properties of the biomaterials. Our previous study indicated that fatty additive; aluminum monostearate (Alst), could improve thermal stability of chitosan sponges. Aim of this study is to investigate an effect of amount of Alst on physicochemical properties of chitosan sponges treated by different heat treatment methods. Two methods of heat treatment including moist heat (autoclave at 121°C, 15 psi for 5 minutes) and dry heat (vacuum heat at 110°C for 24 hours) were …

Preparation And Characterization Of Highly Filled Graphite-Based Polybenzoxazine Composites, A. Pengdam, S. Rimdusit

Journal of Metals, Materials and Minerals

This research aims to study suitable preparation methods and to characterize highly filled graphite composites using polybenzoxazine as a matrix. The high loading of graphite filler was attained in the range of 40 to 80% by wt. due to the very low a-stage viscosity of the benzoxazine resin (BA-a) used. The suitable condition for the compression molding of the highly filled graphite-polybenzoxazine (PBA-a) composites was at temperature of 200°C, and pressure of 15 MPa in the hydraulic hot-press machine for 3 hours to assure a fully cured specimen. The densities of the obtained composites were found to be in a …

Effect Of Silicon On Subcritical Heat Treatment Behavior And Wear Resistance Of 16 Wt% Cr Cast Iron With 2 Wt% Mo, P. Kosasu, S. Inthidech, P. Srichareonchai, Y. Matsubara

Journal of Metals, Materials and Minerals

Effects of Si content on the hardness, decomposition of austenite and abrasive wear resistance during subcritical heat treatment of hypoeutectic 16 wt% Cr -2 wt% Mo cast irons were investigated. The hypoeutectic 16 wt%Cr-2wt% Mo cast irons with 0.5-2.0 wt% Si were prepared. The as-cast specimens were heated up to subcritical temperatures at 50 K intervals from 673K for 14.4 ks ,28.8 ks and 43.2 ks and then, cooled to the room temperature by fan air cooling. In the as-cast state, the hardness increased gradually as Si content increased to 1.5 wt% and then decreased rapidly. The size and the …

Twin-Jet Electropolishing Of Cast Sterling Silver Alloys Using Perchloric Acid And Potassium Cyanide Solutions, W. Kongmuang, T. Chairuangsri, C. Chanmuang

Journal of Metals, Materials and Minerals

Twin-jet electropolishing of Ag-4.87 wt%Cu-0.79 wt%Zn-0.09 wt%Si alloy was studied. Two electrolytes, i.e. potassium cyanide solution in distilled water and glycerol-perchloric acid solution in absolute ethanol, were used in the experiments. Effects of parameters including voltage and electrolyte concentration have been studied. Surface of polishing specimens and artifact formed were characterized by light microscopy and electron microscopy. In general, the potassium cyanide solution is a better electrolyte than the glycerol-perchloric acid solution. A more uniform polishing can be obtained from the potassium cyanide solution at the voltage higher than 5 V. Increasing of the potassium cyanide concentration reduced the electrical …

Study Of Dynamic Vulcanized Pla/Enr Tpv Filled With Various Organic Modified Mmt (Ommt), C. Thongpin, N. Kuttanate, K. Kampuang, N. Suwanwanit

Journal of Metals, Materials and Minerals

In this research, we investigated the crystallization behavior of PLA and properties of PLA/ENR thermoplastic vulcanizates (TPVs). ENR was compounded with phenolic resin and with PLA at the blend ratio of 40/60 by using an internal mixer at 170°C and rotor speed of 70 rpm. Three types of organic modified montmorillonite (OMMT) which are Cloisite® 15A, Cloisite® 20 A and Cloisite® 30B were also added at various contents during mixing. The TPVs were pressed to form thin film in a compression molding machine and cooled down under pressure for 10 minutes. Crystallization behavior, thermal properties and morphology of TPVs were …

Preparation And Catalytic Property Of High Surface Area Mixed Oxides From Calcination Of Mgcucr- And Mgcual-Layered Double Hydroxides, W. Trakarnpruk

Journal of Metals, Materials and Minerals

In this research work layered double hydroxides (LDHs) containing Mg, Cu and Cr(or Al) were prepared with starting Mg:Cu:Cr (or Al) molar ratio of 2:1:1. They were calcined at 500 ºC for 5 h to convert into corresponding mixed oxides possessing high surface area. The catalysts were characterized by chemical analysis (ICP), infrared spectroscopy (FTIR), thermal analysis (TGA/DTA), powder X-ray diffraction (XRD), surface area measurements and H2 temperature programmed reduction (TPR). Catalytic property of these mixed oxides catalysts were tested in the oxidation of ethylbenzene using tertbutylhydroperoxide as an oxidant without added solvent. The experimental results show that high conversion …

Effect Of Catalase And Superoxide Dismutase On Motility, Viability And Acrosomal Integrity Of Canine Spermatozoa During Storage At 5๐c, Khongsak Thiangtum, Tatsuya Hori, Eiichi Kawakami

The Thai Journal of Veterinary Medicine

Preservation of canine spermatozoa at 5๐C is a helpful method for dog breeding management. However, in many species, oxidative damage due to generation of reactive oxygen species (ROS) and long term storage which specifically cause DNA damage, and lipid peroxidation during preservation techniques can cause a decline of sperm motility and fertility capacity. In this study, the effect of antioxidants catalase (CAT) and superoxide dismutase (SOD) on motility, viability and acrosomal integrity of chilled canine semen were investigated. Semen was collected by digital manipulation from 4 dogs (two ejaculates/dog). After removal of seminal plasma, spermatozoa were diluted in egg yolk …

China's Rare Earths Export Quotas: Out Of The China-Raw Materials Gate, But Past The Wto's Finish Line?, Han-Wei Liu, John Maughan

Research Collection Yong Pung How School Of Law

Several recent studies have discussed the ramifications of the China – Raw Materials case for China's rare earths. However, none of these studies has conducted a thorough investigation of China's current export quota regime for rare earths or how it might stand up under WTO rules, assuming that it would be treated the same. This article makes no such assumption, investigating China's export quota regime for rare earths as it stands in early June 2012. The regime is somewhat improved over that applied during the Raw Materials case and could allow a more favourable WTO ruling. However, if General Agreement …

Training Individuals In Function-Based Behavior Intervention Plans Using Modeling, Rehearsal, And Self-Monitoring, Aimee F. Giles

Graduate Theses, Dissertations, and Problem Reports (ETD)

Behavior intervention plans based on the function of problem behavior are more likely to be effective than non-function-based plans. However, plans developed by teachers often do not address behavior function. In addition to ensuring that teachers can write function-based behavior intervention plans, it is also important to ensure plans are implemented with a sufficient degree of fidelity. The purpose of the present study was to evaluate a multi-component training package to train teachers to write function-based behavior intervention plans and to accurately implement differential reinforcement of alternative behavior for escape-maintained problem behavior. Twenty public school teachers of children with emotional …

Exploring The Experiences Of Successful First-Generation College Students At Selected Community Colleges, Jennifer Ann Waters

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to examine how successful FGCS in community colleges addressed challenges they face in order to complete their degree programs. This study was based upon Titno's (1993) Model of Student Departure and explored what methods and programs were most beneficial in helping FGCS overcome the challenges they faced as they worked on their degrees. This study explored each of the three categories discussed: (a) responsive social support; (b) financial preparation and acquisition; and (c) proactive academic preparation and encouragement through the use of semi-structured individual interviews. A more thorough understanding of how to assist FGCS …

Examining The Forces Associated With Heading In Collegiate Soccer Athletes, Elizabeth A. Tenore

Graduate Theses, Dissertations, and Problem Reports (ETD)

Context: Repetitive sub-concussive impacts have recently been recognized as a contributing factor of long-term cognitive deficits. The potential for this to affect soccer players participating at a high level is great due to the constant intentional use of the unprotected head when playing. Examining the force with which a soccer ball strikes an athlete's head during the act of heading is important to determine if there is a potential risk for long term consequences. Objective: The purpose of this study was to determine how much force is associated with heading in soccer. The variability between goal and corner kicks and …