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Measurement of the production fraction times branching fraction $\boldsymbol{ f(b\to\Lambda_{b})\cdot \mathcal{B}(\Lambda_{b}\to J/\psi \Lambda)}$ (open access)

Measurement of the production fraction times branching fraction $\boldsymbol{ f(b\to\Lambda_{b})\cdot \mathcal{B}(\Lambda_{b}\to J/\psi \Lambda)}$

The {Lambda}{sub b}(udb) baryon is observed in the decay {Lambda}{sub b} {yields} J/{psi}{Lambda} using 6.1 fb{sup -1} of p{bar p} collisions collected with the D0 detector at {radical}s = 1.96 TeV. The production fraction multiplied by the branching fraction for this decay relative to that for the decay B{sup 0} {yields} J/{psi}K{sub s}{sup 0} is measured to be 0.345 {+-} 0.034 (stat.) {+-} 0.033 (syst.) {+-} 0.003 (PDG). Using the world average value of f(b {yields} B{sup 0}) {center_dot} {Beta}(B{sup 0} {yields} J/{psi}K{sub s}{sup 0}) = (1.74 {+-} 0.08) x 10{sup -5}, they obtain f(b {yields} {Lambda}{sub b}) {center_dot} {Beta}({Lambda}{sub b} {yields} J/{psi}{Lambda}) = (6.01 {+-} 0.60 (stat.) {+-} 0.58 (syst.) {+-} 0.28 (PDG)) x 10{sup -5}. This measurement represents an improvement in precision by about a factor of three with respect to the current world average.
Date: May 1, 2011
Creator: Abazov, Victor Mukhamedovich; Abbott, Braden Keim; Acharya, Bannanje Sripath; Adams, Mark Raymond; Adams, Todd; Alexeev, Guennadi D. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the $t\bar{t}$ production cross section using dilepton events in $p\bar{p}$ collisions (open access)

Measurement of the $t\bar{t}$ production cross section using dilepton events in $p\bar{p}$ collisions

We present a measurement of the t{bar t} production cross section {sigma}{sub t{bar t}} in p{bar p} collisions at {radical}s = 1.96 TeV using 5.4 fb{sup -1} of integrated luminosity collected with the D0 detector. We consider final states with at least two jets and two leptons (ee, e{mu}, {mu}{mu}), and events with one jet for the the e{mu} final state as well. The measured cross section is {sigma}{sub t{bar t}} = 7.36{sub -0.79}{sup +0.90} (stat + syst) pb. This result combined with the cross section measurement in the lepton + jets final state yields {sigma}{sub t{bar t}} = 7.56{sub -0.56}{sup +0.63}(stat + syst) pb, which agrees with the standard model expectation. The relative precision of 8% of this measurement is comparable to the latest theoretical calculations.
Date: May 1, 2011
Creator: Abazov, Victor Mukhamedovich; Abbott, Braden Keim; Acharya, Bannanje Sripath; Adams, Mark Raymond; Adams, Todd; Alexeev, Guennadi D. et al.
Object Type: Article
System: The UNT Digital Library
Model-independent measurement of $\boldsymbol{t}$-channel single top quark production in $\boldsymbol{p\bar{p}}$ collisions at $\boldsymbol{\sqrt{s}=1.96}$ TeV (open access)

Model-independent measurement of $\boldsymbol{t}$-channel single top quark production in $\boldsymbol{p\bar{p}}$ collisions at $\boldsymbol{\sqrt{s}=1.96}$ TeV

We present a model-independent measurement of t-channel electroweak production of single top quarks in p{bar p} collisions at {radical}s = 1.96 TeV. Using 5.4 fb{sup -1} of integrated luminosity collected by the D0 detector at the Fermilab Tevatron Collider, and selecting events containing an isolated electron or muon, missing transverse energy and one or two jets originating from the fragmentation of b quarks, we measure a cross section {sigma}(p{bar p} {yields} tqb + X) = 2.90 {+-} 0.59 (stat + syst) pb for a top quark mass of 172.5 GeV. The probability of the background to fluctuate and produce a signal as large as the one observed is 1.6 x 10{sup -8}, corresponding to a significance of 5.5 standard deviations.
Date: May 1, 2011
Creator: Abazov, Victor Mukhamedovich; Abbott, Braden Keim; Acharya, Bannanje Sripath; Adams, Mark Raymond; Adams, Todd; Alexeev, Guennadi D. et al.
Object Type: Article
System: The UNT Digital Library
Jacques-Antoine-Hippolyte, comte de Guibert: Father of the Grande Armée (open access)

Jacques-Antoine-Hippolyte, comte de Guibert: Father of the Grande Armée

The eighteenth century was a time of intense upheaval in France. The death of Louis XIV in 1715 and the subsequent reign of Louis XV saw the end of French political and martial hegemony on the continent. While French culture and language remained dominant in Europe, Louis XV's disinterested rule and military stagnation led to the disastrous defeat of the French army at the hands of Frederick the Great of Prussia in the Seven Years War (1756-1763). The battle of Rossbach marked the nadir of the French army in the Seven Years War. Frederick's army routed the French infantry that had bumbled its way into massed Prussian cavalry. Following the war, two reformist elements emerged in the army. Reformers within the government, chiefly Etienne François, duc de Choiseul, sought to rectify the army's poor performance and reconstitute France's military establishment. Outside the traditional army structure, military thinkers looked to military theory to reinvigorate the army from within and without. Foremost among the latter was a young officer named Jacques-Antoine-Hippolyte de Guibert, whose 1772 Essai général de tactique quickly became the most celebrated work of theory in European military circles. The Essai provided a new military constitution for France, proposing wholesale …
Date: May 2011
Creator: Abel, Jonathan, 1985-
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Relationship Between Supplemental Instruction Leader Learning Style and Study Session Design (open access)

The Relationship Between Supplemental Instruction Leader Learning Style and Study Session Design

The purpose of this qualitative study was to examine the learning styles of supplemental instruction leaders at a large, public university during the fall 2010 semester and determine whether or not their personal learning styles influenced the way they designed and developed out-of-class study sessions. The total population of supplemental instruction leaders was 37, of which 24 were eligible to participate in the study. Of the 24 eligible supplemental instruction leaders, 20 completed the entire study. Participants in the study included nine male and 11 female supplemental instruction leaders with a median age of 22.25 years-old. Seventeen participants indicated their classification as senior, two as junior, and one as sophomore. Of the participants, 16 indicated white as a race or ethnicity, one indicated Asian, two indicated African American, and one indicated both American Indian/Alaska Native and white. Supplemental instruction leader learning style was assessed using the Kolb Learning Style Inventory. Leaders were then interviewed, and their study sessions were analyzed. Through triangulation of data from learning style, interviews and actual study session documents, four major themes emerged. The four themes were: 1) incorporation of personal experience into study session design, 2) the sense of impact on student learning, 3) a …
Date: May 2011
Creator: Adams, Joshua
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Solvent Effects and Bioconcentration Patterns of Antimicrobial Compounds in Wetland Plants (open access)

Solvent Effects and Bioconcentration Patterns of Antimicrobial Compounds in Wetland Plants

This study looked at effects of organic solvents dimethylsulfoxide, dimethylformamide and acetone at 0.01%, 0.05% and 0.1% concentration on germination and seedling development wetland plants. Even at 0.01% level, all solvents affected some aspect of seed germination or seedling growth. Acetone at 0.01% was least toxic. Root morphological characteristics were most sensitive compared to shoot morphological characteristics. This study also looked at bioconcentration patterns of antimicrobial compounds triclosan, triclocarban and methyl-triclosan in wetland plants exposed to Denton Municipal Waste Water Treatment Plant effluent. Bioconcentration patterns of antimicrobial compounds varied among species within groups as well as within organs of species. The highest triclocarban, triclosan and methyltriclosan concentration were in shoot of N. guadalupensis, root of N. lutea and in shoots of P. nodous respectively.
Date: May 2011
Creator: Adhikari, Sajag
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Taming transport in InN (open access)

Taming transport in InN

The large electron affinity of InN, close to 6 eV and the largest of any III-V semiconductor, creates a strong driving force for native donor formation, both in the bulk and at surfaces and interfaces. Moreover, all InN surfaces, regardless of crystal orientation or doping, have been observed to have a surface accumulation layer of electrons, which interferes with standard electrical measurements. For these reasons, until recently, it was uncertain whether or not compensation by donor defects would prevent “real” p-type activity (i.e. existence of sufficiently shallow acceptors and mobile holes). A coordinated experimental approach using a combination of electrical (Hall effect) and electrothermal (Seebeck coefficient) measurements will be described that allows definitive evaluation of carrier transport in InN. In Mg-doped InN films, the sensitivity of thermopower to bulk hole conduction, combined with modeling of the parallel conducting layers (surface/bulk/interface), enables quantitative measurement of the free hole concentration and mobility. In undoped (n-type) material, combined Hall and thermopower measurements, along with a considering of the scattering mechanisms, leads to a quantitative understanding of the crucial role of charged line defects in limiting electron transport.
Date: May 29, 2011
Creator: Ager, Joel W., III & Miller, Nate R.
Object Type: Article
System: The UNT Digital Library
Biological Interactions and Dynamics Science Theme Advisory Panel (BID-STAP) (open access)

Biological Interactions and Dynamics Science Theme Advisory Panel (BID-STAP)

This report contains the charge to the panel, the panel's discussions and panel recommendations.
Date: May 1, 2011
Creator: Ahring, Birgitte K.; Baliga, Nitin S.; Frederickson, James R.; Kaplan, Samuel; Pakrasi, Himadri B.; Pounds, Joel G. et al.
Object Type: Report
System: The UNT Digital Library
Using Cool Roofs to Reduce Energy Use, Greenhouse Gas Emissions, and Urban Heat-island Effects: Findings from an India Experiment (open access)

Using Cool Roofs to Reduce Energy Use, Greenhouse Gas Emissions, and Urban Heat-island Effects: Findings from an India Experiment

Cool roofs, cool pavements, and urban vegetation reduce energy use in buildings, lower local air pollutant concentrations, and decrease greenhouse gas emissions from urban areas. This report summarizes the results of a detailed monitoring project in India and related simulations of meteorology and air quality in three developing countries. The field results quantified direct energy savings from installation of cool roofs on individual commercial buildings. The measured annual energy savings potential from roof-whitening of previously black roofs ranged from 20-22 kWh/m2 of roof area, corresponding to an air-conditioning energy use reduction of 14-26% in commercial buildings. The study estimated that typical annual savings of 13-14 kWh/m2 of roof area could be achieved by applying white coating to uncoated concrete roofs on commercial buildings in the Metropolitan Hyderabad region, corresponding to cooling energy savings of 10-19%. With the assumption of an annual increase of 100,000 square meters of new roof construction for the next 10 years in the Metropolitan Hyderabad region, the annual cooling energy savings due to whitening concrete roof would be 13-14 GWh of electricity in year ten alone, with cumulative 10-year cooling energy savings of 73-79 GWh for the region. The estimated savings for the entire country would …
Date: May 25, 2011
Creator: Akbari, Hashem; Xu, Tengfang; Taha, Haider; Wray, Craig; Sathaye, Jayant; Garg, Vishal et al.
Object Type: Report
System: The UNT Digital Library
Consensus Building in Sensor Networks and Long Term Planning for the National Airspace System (open access)

Consensus Building in Sensor Networks and Long Term Planning for the National Airspace System

In this thesis, I present my study on the impact of multi-group network structure on the performance of consensus building strategies, and the preliminary mathematical formulation of the problem on improving the performance of the National Airspace system (NAS) through long-term investment. The first part of the thesis is concerned with a structural approach to the consensus building problem in multi-group distributed sensor networks (DSNs) that can be represented by bipartite graph. Direct inference of the convergence behavior of consensus strategies from multi-group DSN structure is one of the contributions of this thesis. The insights gained from the analysis facilitate the design and development of DSNs that meet specific performance criteria. The other part of the thesis is concerned with long-term planning and development of the NAS at a network level, by formulating the planning problem as a resource allocation problem for a flow network. The network-level model viewpoint on NAS planning and development will give insight to the structure of future NAS and will allow evaluation of various paradigms for the planning problem.
Date: May 2011
Creator: Akula, Naga Venkata Swathik
Object Type: Thesis or Dissertation
System: The UNT Digital Library
A Regional Seismic Array of Three-Component Stations in Central Saudi Arabia (open access)

A Regional Seismic Array of Three-Component Stations in Central Saudi Arabia

None
Date: May 4, 2011
Creator: Al-Amri, A.; Harris, D.; Fnais, M.; Rodgers, A. & Hemaida, M.
Object Type: Article
System: The UNT Digital Library
Modeling Student Perception of Web 2.0 Technologies Adoption in Kuwait (open access)

Modeling Student Perception of Web 2.0 Technologies Adoption in Kuwait

The primary focus of this dissertation was to explore students' perceptions of adopting Web 2.0 applications at the School of Basic Education (SBE) in Kuwait. Although Web 2.0 applications are becoming more popular among the digital generation, there is still no evidence of students' perceptions of adopting the innovation of Web 2.0 technologies in Kuwait. The problem this study addresses is that the current status of Web 2.0 technologies usage by academic students has remained educationally unknown in Kuwait. Therefore, there was a need to investigate the extent to which academic students in SBE are aware of and their usage of Web 2.0 technologies, as well as the factors and obstacles that affect using these technologies. Rogers' diffusion of innovation theory (DoI) is employed in this study to specify the factors that influence student perceptions of adopting Web 2.0 applications as learning tools. Data used in this dissertation was gathered via a survey instrument from 350 students at the SBE and was statistically analyzed to find out the answers of the research questions. This study identified the low rate of Web 2.0 awareness and adoption by the students. Descriptive statistical analysis, such as mean scores and standard deviation, were used …
Date: May 2011
Creator: Alajmi, Mohammad
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Development of a micro flow-through cell for high field NMR spectroscopy. (open access)

Development of a micro flow-through cell for high field NMR spectroscopy.

A highly transportable micro flow-through detection cell for nuclear magnetic resonance (NMR) spectroscopy has been designed, fabricated and tested. This flow-through cell allows for the direct coupling between liquid chromatography (LC) and gel permeation chromatography (GPC) resulting in the possibility of hyphenated LC-NMR and GPC-NMR. The advantage of the present flow cell design is that it is independent and unconnected to the detection probe electronics, is compatible with existing commercial high resolution NMR probes, and as such can be easily implemented at any NMR facility. Two different volumes were fabricated corresponding to between {approx}3.8 and 10 {micro}L detection volume. Examples of the performance of the cell on different NMR instruments, and using different NMR detection probes were demonstrated.
Date: May 1, 2011
Creator: Alam, Todd Michael & McIntyre, Sarah K.
Object Type: Report
System: The UNT Digital Library
CdTe Feedstock Development and Validation: Cooperative Research and Development Final Report, CRADA Number CRD-08-00280 (open access)

CdTe Feedstock Development and Validation: Cooperative Research and Development Final Report, CRADA Number CRD-08-00280

The goal of this work was to evaluate different CdTe feedstock formulations (feedstock provided by Redlen) to determine if they would significantly improve CdTe performance with ancillary benefits associated with whether changes in feedstock would affect CdTe cell processing and possibly reliability of cells. Feedstock also included attempts to intentionally dope the CdTe with pre-selected elements.
Date: May 1, 2011
Creator: Albin, D.
Object Type: Report
System: The UNT Digital Library

Retrospective Digitization of Theses and Dissertations: Revisiting Issues and Considerations

Poster presented at the 2011 U.S. ETD Annual Conference. The poster describes the digitization of theses and dissertations at the University of North Texas (UNT) Libraries.
Date: May 2011
Creator: Alemneh, Daniel Gelaw & Phillips, Mark Edward
Object Type: Poster
System: The UNT Digital Library
CP Violation in D0-D0bar Mixing and Electric Dipole Moments in SUSY Alignment Models (open access)

CP Violation in D0-D0bar Mixing and Electric Dipole Moments in SUSY Alignment Models

We report on a study of CP Violation in D{sup 0}-{bar D}{sup 0} mixing and Electric Dipole Moments in the framework of supersymmetric alignment models. Both classes of observables are strongly suppressed in the Standard Model and highly sensitive to new sources of flavor and CP violation that can be present in models of New Physics. Supersymmetric alignment models generically predict large non-standard effects in D{sup 0}-{bar D}{sup 0} mixing and we show that visible CP violation in D{sup 0}-{bar D}{sup 0} mixing implies lower bounds for the EDMs of hadronic systems, like the neutron EDM and the mercury EDM, in the reach of future experimental sensitivities. We also give updated constraints on the mass insertions of the Minimal Supersymmetric Standard Model using the current data on D{sup 0}-{bar D}{sup 0} mixing.
Date: May 1, 2011
Creator: Altmannshofer, Wolfgang
Object Type: Article
System: The UNT Digital Library
Retinoic acid Treatment Affects Kidney Development and Osmoregulatory System in the Developing Chicken (Gallus Gallus) (open access)

Retinoic acid Treatment Affects Kidney Development and Osmoregulatory System in the Developing Chicken (Gallus Gallus)

Development is a dynamic process characterized by critical periods in which organ systems are sensitive to changes in the surrounding environment. In the current study, critical windows of embryonic growth and kidney development were assessed in the embryonic chicken. All‐trans retinoic acid (tRA) influences not only organogenesis and cell proliferation, but also targets metanephric kidney nephrogenesis. Embryonic chickens were given a single injection of tRA on embryonic day 8. tRA decreased embryo, kidney, and heart mass from day 16 to day 18. However, mass specific kidney and heart masses showed no differences. Whole blood, plasma, and allantoic fluid osmolality were altered in tRA treated embryos from day 16 to day 18. In addition, hematocrit, red blood cell count, and hemoglobin concentration were altered in tRA treated embryos. The results suggest that although nephrogenesis was not affected by tRA, the developing osmoregulatory system was altered in tRA treated embryos.
Date: May 2011
Creator: Alvine, Travis Douglas
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Southwest Retort, Volume 63, Number 9, May 2012 (open access)

Southwest Retort, Volume 63, Number 9, May 2012

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2011
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
The Newsletter of the Texas Chapter of the American Fisheries Society, Volume 37, Number 2, Spring 2011 (open access)

The Newsletter of the Texas Chapter of the American Fisheries Society, Volume 37, Number 2, Spring 2011

Newsletter of the Texas Chapter of the American Fisheries Society containing information about the organization, membership, and field of aquaculture and ecosystem management.
Date: May 2011
Creator: American Fisheries Society. Texas Chapter.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Advanced High-Speed Framing Camera Development for Fast, Visible Imaging Experiments (open access)

Advanced High-Speed Framing Camera Development for Fast, Visible Imaging Experiments

The advances in high-voltage switching developed in this project allow a camera user to rapidly vary the number of output frames from 1 to 25. A high-voltage, variable-amplitude pulse train shifts the deflection location to the new frame location during the interlude between frames, making multiple frame counts and locations possible. The final deflection circuit deflects to five different frame positions per axis, including the center position, making for a total of 25 frames. To create the preset voltages, electronically adjustable {+-}500 V power supplies were chosen. Digital-to-analog converters provide digital control of the supplies. The power supplies are clamped to {+-}400 V so as not to exceed the voltage ratings of the transistors. A field-programmable gated array (FPGA) receives the trigger signal and calculates the combination of plate voltages for each frame. The interframe time and number of frames are specified by the user, but are limited by the camera electronics. The variable-frame circuit shifts the plate voltages of the first frame to those of the second frame during the user-specified interframe time. Designed around an electrostatic image tube, a framing camera images the light present during each frame (at the photocathode) onto the tube’s phosphor. The phosphor persistence …
Date: May 11, 2011
Creator: Amy Lewis, Stuart Baker, Brian Cox, Abel Diaz, David Glass, Matthew Martin
Object Type: Article
System: The UNT Digital Library
Novel Insights into the Diversity of Catabolic Metabolism from Ten Haloarchaeal Genomes (open access)

Novel Insights into the Diversity of Catabolic Metabolism from Ten Haloarchaeal Genomes

The extremely halophilic archaea are present worldwide in saline environments and have important biotechnological applications. Ten complete genomes of haloarchaea are now available, providing an opportunity for comparative analysis. We report here the comparative analysis of five newly sequenced haloarchaeal genomes with five previously published ones. Whole genome trees based on protein sequences provide strong support for deep relationships between the ten organisms. Using a soft clustering approach, we identified 887 protein clusters present in all halophiles. Of these core clusters, 112 are not found in any other archaea and therefore constitute the haloarchaeal signature. Four of the halophiles were isolated from water, and four were isolated from soil or sediment. Although there are few habitat-specific clusters, the soil/sediment halophiles tend to have greater capacity for polysaccharide degradation, siderophore synthesis, and cell wall modification. Halorhabdus utahensis and Haloterrigena turkmenica encode over forty glycosyl hydrolases each, and may be capable of breaking down naturally occurring complex carbohydrates. H. utahensis is specialized for growth on carbohydrates and has few amino acid degradation pathways. It uses the non-oxidative pentose phosphate pathway instead of the oxidative pathway, giving it more flexibility in the metabolism of pentoses. These new genomes expand our understanding of haloarchaeal …
Date: May 3, 2011
Creator: Anderson, Iain; Scheuner, Carmen; Goker, Markus; Mavromatis, Kostas; Hooper, Sean D.; Porat, Iris et al.
Object Type: Article
System: The UNT Digital Library

Web Archives: Outreach Strategy Task Force Proposal Review

Presentation for the 2011 International Internet Preservation Consortium General Assembly. This presentation discusses the International Internet Preservation Consortium's plans to increase awareness of web archiving activities and standards through outreach.
Date: May 11, 2011
Creator: Anderson, Martha
Object Type: Presentation
System: The UNT Digital Library
Nuclear Power Plant Design and Seismic Safety Considerations (open access)

Nuclear Power Plant Design and Seismic Safety Considerations

This report presents some of the general design concepts of operating nuclear power plants in order to discuss design considerations for seismic events. This report does not attempt to conclude whether one design is inherently safer or less safe than another plant. Nor does it attempt to conclude whether operating nuclear power plants are at any greater or lesser risk from earthquakes given recent updates to seismic data and seismic hazard maps.
Date: May 2, 2011
Creator: Andrews, Anthony
Object Type: Report
System: The UNT Digital Library
Organizational Alignment (open access)

Organizational Alignment

This paper discusses organizational alignment and digital preservation.
Date: May 23, 2011
Creator: Angevaare, Inge; Gallinger, Michelle; Anderson, Martha; Giaretta, David & Halbert, Martin
Object Type: Paper
System: The UNT Digital Library