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1,226 Matching Results
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An Atomic Gravitational Wave Interferometric Sensor (AGIS)
We propose two distinct atom interferometer gravitational wave detectors, one terrestrial and another satellite-based, utilizing the core technology of the Stanford 10m atom interferometer presently under construction. Each configuration compares two widely separated atom interferometers run using common lasers. The signal scales with the distance between the interferometers, which can be large since only the light travels over this distance, not the atoms. The terrestrial experiment with baseline {approx} 1 km can operate with strain sensitivity {approx} 10{sup -19}/{radical}Hz in the 1 Hz-10 Hz band, inaccessible to LIGO, and can detect gravitational waves from solar mass binaries out to megaparsec distances. The satellite experiment with baseline {approx} 1000 km can probe the same frequency spectrum as LISA with comparable strain sensitivity {approx} 10{sup -20}/{radical}Hz. The use of ballistic atoms (instead of mirrors) as inertial test masses improves systematics coming from vibrations, acceleration noise, and significantly reduces spacecraft control requirements. We analyze the backgrounds in this configuration and discuss methods for controlling them to the required levels.
Date:
August 1, 2008
Creator:
Dimopoulos, Savas; Graham, Peter W.; Hogan, Jason M.; Kasevich, Mark A. & Rajendran, Surjeet
Object Type:
Report
System:
The UNT Digital Library
Mesoscale Characterization of Coupled Hydromechanical Behavior of a Fractured Porous Slope in Response to Free Water-Surface Movement
To better understand the role of groundwater-level changes on rock-slope deformation and damage, a carbonate rock slope (30 m x 30 m x 15 m) was extensively instrumented for mesoscale hydraulic and mechanical measurements during water-level changes. The slope is naturally drained by a spring that can be artificially closed or opened by a water gate. In this study, a 2-hour slope-dewatering experiment was analyzed. Changes in fluid pressure and deformation were simultaneously monitored, both at discontinuities and in the intact rock, using short-base extensometers and pressure gauges as well as tiltmeters fixed at the slope surface. Field data were analyzed with different coupled hydromechanical (HM) codes (ROCMAS, FLAC{sup 3D}, and UDEC). Field data indicate that in the faults, a 40 kPa pressure fall occurs in 2 minutes and induces a 0.5 to 31 x 10{sup -6} m normal closure. Pressure fall is slower in the bedding-planes, lasting 120 minutes with no normal deformation. No pressure change or deformation is observed in the intact rock. The slope surface displays a complex tilt towards the interior of the slope, with magnitudes ranging from 0.6 to 15 x 10{sup -6} rad. Close agreement with model for both slope surface and internal measurements …
Date:
May 15, 2008
Creator:
Rutqvist, Jonny; Guglielmi, Y.; Cappa, F.; Rutqvist, J.; Tsang, C.-F. & Thoraval, A.
Object Type:
Article
System:
The UNT Digital Library
Discovery of a Giant Lya Emitter Near the Reionization Epoch
We report the discovery of a giant Ly{alpha} emitter (LAE) with a Spitzer/IRAC counterpart near the reionization epoch at z = 6.595. The giant LAE is found from the extensive 1 deg{sup 2} Subaru narrow-band survey for z = 6.6 LAEs in the Subaru/XMM-Newton Deep Survey (SXDS) field, and subsequently identified by deep spectroscopy of Keck/DEIMOS and Magellan/IMACS. Among our 207 LAE candidates, this LAE is not only the brightest narrow-band object with L(Ly{alpha}) = 3.9 {+-} 0.2 x 10{sup 43} erg s{sup -1} in our survey volume of 10{sup 6} Mpc{sup 3}, but also a spatially extended Ly{alpha} nebula with the largest isophotal area whose major axis is at least {approx_equal} 3-inches. This object is more likely to be a large Ly{alpha} nebula with a size of {approx}> 17-kpc than to be a strongly-lensed galaxy by a foreground object. Our Keck spectrum with medium-high spectral and spatial resolutions suggests that the velocity width is v{sub FWHM} = 251 {+-} 21 km s{sup -1}, and that the line-center velocity changes by {approx_equal} 60 km s{sup -1} in a 10-kpc range. The stellar mass and star-formation rate are estimated to be 0.9-5.0 x 10{sup 10}M{sub {circle_dot}} and > 34 M{sub {circle_dot}}yr{sup …
Date:
August 1, 2008
Creator:
Ouchi, Masami; Ono, Yoshiaki; Egami, Eiichi; Saito, Tomoki; Oguri, Masamune; McCarthy, Patrick J. et al.
Object Type:
Article
System:
The UNT Digital Library
Post-Translational Modifications of Desulfovibrio vulgaris Hildenborough Sulfate Reduction Pathway Proteins
Recent developments in shotgun proteomics have enabled high-throughput studies of a variety of microorganisms at a proteome level and provide experimental validation for predicted open reading frames in the corresponding genome. More importantly, advances in mass spectrometric data analysis now allow mining of large proteomics data sets for the presence of post-translational modifications(PTMs). Although PTMs are a critical aspectof cellular activity, such information eludes cell-wide studies conducted at the transcript level. Here, we analyze several mass spectrometric data sets acquired using two-dimensional liquid chromatography tandem mass spectrometry, 2D-LC/MS/MS, for the sulfate reducing bacterium, Desulfovibrio vulgaris Hildenborough. Our searches of the raw spectra led us to discover several post-translationally modified peptides in D. vulgaris. Of these, several peptides containing a lysine with a +42 Da modification were found reproducibly across all data sets. Both acetylation and trimethylation have the same nominal +42 Da mass, and are therefore candidates for this modification. Several spectra were identified having markers for trimethylation, while one is consistent with an acetylation. Surprisingly, these modified peptides predominantly mapped to proteins involved in sulfate respiration. Other highly expressed proteins in D. vulgaris, such as enzymes involved in electron transport and other central metabolic processes, did not contain this …
Date:
March 1, 2008
Creator:
Gaucher, S. P.; Redding, A. M.; Mukhopadhyay, A.; Keasling, J. D. & Singh, A. K.
Object Type:
Article
System:
The UNT Digital Library
Characterization of Vadose Zone Sediment: Slant Borehole SX-108 in the S-SX Waste Management Area
This report was revised in September 2008 to remove acid-extractable sodium data from Table 4.17. The sodium data was removed due to potential contamination introduced during the acid extraction process. The rest of the text remains unchanged from the original report issued in February 2002. The overall goal of the of the Tank Farm Vadose Zone Project, led by CH2M HILL Hanford Group, Inc., is to define risks from past and future single-shell tank farm activities. To meet this goal, CH2M HILL Hanford Group, Inc., asked scientists from Pacific Northwest National Laboratory to perform detailed analyses on vadose zone sediment from within the S-SX Waste Management Area. This report is the fourth in a series of four reports to present the results of these analyses. Specifically, this report contains all the geologic, geochemical, and selected physical characterization data collected on vadose zone sediment recovered from a slant borehole installed beneath tank SX-108 (or simply SX-108 slant borehole).
Date:
September 11, 2008
Creator:
Serne, R. Jeffrey; Last, George V.; Schaef, Herbert T.; Lanigan, David C.; Lindenmeier, Clark W.; Ainsworth, Calvin C. et al.
Object Type:
Report
System:
The UNT Digital Library
Perceptions of Faculty Development: A Study of a North Texas Community College
This dissertation study deems faculty development critical to meeting challenges associated with retirement, potential professor shortages, increasing adjunct populations, unprepared faculty, and accreditation standards in the community college. The study centers on seeking a current, in-depth understanding of faculty development at Metro Community College (a pseudonym). The participants in this qualitative study consisted of adjunct and full-time faculty members and administrators who communicated their perceptions of faculty development. The analysis discovered faculty member types (progressive and hobbyist adjunct and proactive, active, and reactive full-time faculty) who invest themselves in development differently depending on their position and inclination to participate. Faculty members generally indicated a desire for collegiality and collaboration, self-direction, and individualized approaches to development whereas administrators exhibited a greater interest in meeting accreditation standards and ensuring institutional recognition. The study also discovered a need to consider development initiatives for adjunct faculty members. The dissertation proposes an improved partnership between the adjunct and full-time faculty and the administration.
Date:
December 2008
Creator:
Bodily, Brett Hogan
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Geochemical Characterization of Chromate Contamination in the 100 Area Vadose Zone at the Hanford Site
The major objectives of the proposed study were to: 1.) determine the leaching characteristics of hexavalent chromium [Cr(VI)] from contaminated sediments collected from 100 Area spill sites; 2.) elucidate possible Cr(VI) mineral and/or chemical associations that may be responsible for Cr(VI) retention in the Hanford Site 100 Areas through the use of i.) macroscopic leaching studies and ii.) microscale characterization of contaminated sediments; and 3.) provide information to construct a conceptual model of Cr(VI) geochemistry in the Hanford 100 Area vadose zone. In addressing these objectives, additional benefits accrued were: (1) a fuller understanding of Cr(VI) entrained in the vadose zone that will that can be utilized in modeling potential Cr(VI) source terms, and (2) accelerating the Columbia River 100 Area corridor cleanup by providing valuable information to develop remedial action based on a fundamental understanding of Cr(VI) vadose zone geochemistry. A series of macroscopic column experiments were conducted with contaminated and uncontaminated sediments to study Cr(VI) desorption patterns in aged and freshly contaminated sediments, evaluate the transport characteristics of dichromate liquid retrieved from old pipelines of the 100 Area; and estimate the effect of strongly reducing liquid on the reduction and transport of Cr(VI). Column experiments used the < …
Date:
July 16, 2008
Creator:
Dresel, P. Evan; Qafoku, Nikolla; McKinley, James P.; Fruchter, Jonathan S.; Ainsworth, Calvin C.; Liu, Chongxuan et al.
Object Type:
Report
System:
The UNT Digital Library
Observation of B^+\to\eta\rho^+ and Search for B^0 Decays to\eta^\prime\eta, \eta\pi^0, \eta^\prime\pi^0, and \omega\pi^0
The authors present measurements of branching fractions for five B-meson decays to two-body charmless final states. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 459 million B{bar B} pairs. The results for branching fractions are, in units of 10{sup -6} (upper limits at 90% C.L.): {Beta}(B{sup +} {yields} {eta}{rho}{sup +}) = 9.9 {+-} 1.2 {+-} 0.8, {Beta}(B{sup 0} {yields} {eta}{prime}{eta}) = 0.5 {+-} 0.4 {+-} 0.1 (< 1.2), {Beta}(B{sup 0} {yields} {eta}{pi}{sup 0}) = 0.9 {+-} 0.4 {+-} 0.1 (< 1.5), {Beta}(B{sup 0} {yields} {eta}{prime}{pi}{sup 0}) = 0.9 {+-} 0.4 {+-} 0.1 (< 1.5), and {Beta}(B{sup 0}{sup 0} {yields} {omega}{pi}{sup 0}) = {eta}{rho}{sup +} mode, they measure the charge asymmetry {Alpha}{sub ch} (B{sup +} {yields} {eta}{rho}{sup +}) = 0.13 {+-} 0.11 {+-} 0.02.
Date:
April 22, 2008
Creator:
Aubert, Bernard; Bona, Marcella; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type:
Article
System:
The UNT Digital Library
Climate Projections Based on Emissions Scenarios for Long-Lived and Short-Lived Radiatively Active Gases and Aerosols
This report focuses on the Climate Projections Based on Emissions Scenarios. The influence of greenhouse gases and particle pollution on our present and future climate has been widely examined. While both long-lived (e.g., carbon dioxide) and short-lived (e.g., soot) gases and particles affect the climate, other projections of future climate, such as the IPCC reports focus largely on the long-lived gases. This U.S. Climate Change Science Program Synthesis and Assessment Product provides a different emphasis. The authors examine the effect of long-lived greenhouse gases on the global climate based on updated emissions scenarios produced by another CCSP Synthesis and Assessment Product (SAP 2.1a). In these scenarios, atmospheric concentrations of the long-lived greenhouse gases leveled off, or stabilized, at predetermined levels by the end of the twenty-first century (unlike in the IPCC scenarios). However, the projected future temperature changes fall within the same range as those projected for the latest IPCC report. The authors confirm the robust future warming signature and other associated changes in the climate.
Date:
September 2008
Creator:
U.S. Climate Change Science Program and the Subcommittee on Global Change Research
Object Type:
Book
System:
The UNT Digital Library
DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS USING ARP PRODUCT SIMULANT AND SB4 TANK 40 SLUDGE SLURRY
The radioactive startup of two new SRS processing facilities, the Actinide Removal Process (ARP) and the Modular Caustic-Side-Solvent-Extraction Unit (MCU) will add two new waste streams to the Defense Waste Processing Facility (DWPF). The ARP will remove actinides from the 5.6 M salt solution resulting in a sludge-like product that is roughly half monosodium titanate (MST) insoluble solids and half sludge insoluble solids. The ARP product will be added to the Sludge Receipt and Adjustment Tank (SRAT) at boiling and dewatered prior to pulling a SRAT receipt sample. The cesium rich MCU stream will be added to the SRAT at boiling after both formic and nitric acid have been added and the SRAT contents concentrated to the appropriate endpoint. A concern was raised by an external hydrogen review panel that the actinide loaded MST could act as a catalyst for hydrogen generation (Mar 15, 2007 report, Recommendation 9). Hydrogen generation, and it's potential to form a flammable mixture in the off-gas, under SRAT and Slurry Mix Evaporator (SME) processing conditions has been a concern since the discovery that noble metals catalyze the decomposition of formic acid. Radiolysis of water also generates hydrogen, but the radiolysis rate is orders of magnitude …
Date:
May 14, 2008
Creator:
Lambert, D; John Pareizs, J; Bradley Pickenheim, B; Cj Bannochie, C; Michael Stone, M; Damon Click, D et al.
Object Type:
Report
System:
The UNT Digital Library
Individual attachment styles and the correspondence/compensation hypotheses in relation to depression and depressive experiences.
Two hundred twenty individuals participated in the present study from a university population. The study examined the relationship among attachment styles to caregivers, relationship with God, depressive symptomology, and depressive experiences. Attachment theorists have suggested a connection between childhood attachment to caregivers and current attachment to God through the idea that individuals have "working models" that form how they interpret present relationships. For the most part, the results of the current study supported the idea of correspondence between attachment to caregiver and attachment to God. Individual attachment styles to caregivers matched their attachment style to God. However, when caregiver religiousness was included as a moderating variable, results supported the theory of combined compensation-correspondence for those with insecure attachments to caregivers. Individuals with insecure attachment to caregivers were more likely to compensate for their insecure attachment bonds through participation in religious activity, whereas their internal, private relationship with God corresponded with their previous insecure attachment bonds. Individuals with insecure attachment to caregivers were more likely to endorse symptoms of depression and report introjective, but not anaclitic, depressive experiences. With respect to attachment to God, introjective depressive experiences were positively related to both anxious and avoidant attachments, whereas, anaclitic depressive experiences were …
Date:
August 2008
Creator:
Hill, Mary Kathleen
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Collected Papers from Past Texas Archeological Society Summer Field Schools
Series of articles documenting four Texas Archeological Society Field Schools, describing each of the projects including the environment, cultural context, and archaeological findings.
Date:
2008
Creator:
Perttula, Timothy K.
Object Type:
Book
System:
The Portal to Texas History
Preliminary Review of Adaptation Options for Climate-Sensitive Ecosystems and Resources
The U.S. Government's Climate Change Science Program (CCSP) is responsible for providing the best science-based knowledge possible to inform management of the risks and opportunities associated with changes in the climate and related environmental systems. To support its mission, the CCSP has commissioned 21 "synthesis and assessment products" (SAPs) to advance decision making on climate change-related issues by providing current evaluations of climate change science and identifying priorities for research, observation, and decision support. This Report-SAP 4.4-focuses on federally managed lands and waters to provide a "Preliminary Review of Adaptation Options for Climate-Sensitive Ecosystems and Resources." It is one of seven reports that support Goal 4 of the CCSP Strategic Plan to understand the sensitivity and adaptability of different natural and managed ecosystems and human systems to climate and related global changes. The purpose of SAP 4.4 is to provide useful information on the state of knowledge regarding adaptation options for key, representative ecosystems and resources that may be sensitive to climate variability and change. As its title suggests, this report is a preliminary review, defined as "the process of collecting and reviewing available information about known or potential adaptation options."
Date:
June 2008
Creator:
U.S. Climate Change Science Program and the Subcommittee on Global Change Research
Object Type:
Book
System:
The UNT Digital Library
Adolescent Self-Mutilating Behaviors: Experiential Avoidance Coupled with Imitation?
Repetitive self-mutilation (RSM) has become increasingly prevalent among adolescents. Empirical research has pinpointed several correlates of this behavior, but the initiation and maintenance of RSM among adolescents are not well understood. The experiential avoidance model (EAM) proposes that self-mutilation is a behavior that allows for the avoidance or alteration of unwanted internal experiences, and that it is negatively reinforced with repetition. The current study explored the usefulness of the EAM as an explanatory theory for adolescent RSM, with the additional incorporation of issues of social context. Adolescents (N = 211) from three school-based samples completed self-report questionnaires. One-third of students reported at least one incident of purposeful, non-suicidal self-mutilation and 16% had engaged in self-mutilation repeatedly within the past 6 months. Both regression and group analyses indicated that adolescents who engage in RSM report greater psychological distress, a greater incidence of functionally equivalent behaviors, and greater exposure to self-mutilation among peers and/or in the media, when compared to their counterparts who have not engaged in RSM. Suicidal ideation/behaviors were consistently the strongest predictors of current self-mutilation behaviors. Clinical implications, limitations, and suggestions for future research are discussed.
Date:
August 2008
Creator:
Howe-Martin, Laura S.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Ten Spurs, Volume 2, 2008
Annual publication of The Mayborn Literary Nonfiction Conference held by the Frank W. Mayborn Graduate Institute of Journalism. This volume includes the eleven literary non-fiction pieces selected from the conference submissions as well as illustrations and author biographies.
Date:
2008
Creator:
Getschow, George
Object Type:
Journal/Magazine/Newsletter
System:
The UNT Digital Library
Joint Groundwater Monitoring and Contamination Report: 2007
Annual report compiling information about required groundwater monitoring activities and cases of contamination by state-regulated activities during the YYYY calendar year. Includes tables with the enforcement status of each case of contamination.
Date:
June 2008
Creator:
Texas Groundwater Protection Committee
Object Type:
Report
System:
The Portal to Texas History
Jewish Herald-Voice (Houston, Tex.), Vol. 100, No. 29, Ed. 1 Thursday, October 16, 2008
Weekly Jewish newspaper from Houston, Texas that includes local, state and national news along with extensive advertising.
Date:
October 16, 2008
Creator:
Samuels, Jeanne F.
Object Type:
Newspaper
System:
The Portal to Texas History
Aspen Ecology in Rocky Mountain National Park: Age Distribution, Genetics, and the Effects of Elk Herbivory
Lack of aspen (Populus tremuloides) recruitment and canopy replacement of aspen stands that grow on the edges of grasslands on the low-elevation elk (Cervus elaphus) winter range of Rocky Mountain National Park (RMNP) in Colorado has been a cause of concern for more than 70 years (Packard, 1942; Olmsted, 1979; Stevens, 1980; Hess, 1993; R.J. Monello, T.L. Johnson, and R.G. Wright, Rocky Mountain National Park, 2006, written commun.). These aspen stands are a significant resource since they are located close to the park's road system and thus are highly visible to park visitors. Aspen communities are integral to the ecological structure of montane and subalpine landscapes because they contain high native species richness of plants, birds, and butterflies (Chong and others, 2001; Simonson and others, 2001; Chong and Stohlgren, 2007). These low-elevation, winter range stands also represent a unique component of the park's plant community diversity since most (more than 95 percent) of the park's aspen stands grow in coniferous forest, often on sheltered slopes and at higher elevations, while these winter range stands are situated on the low-elevation ecotone between the winter range grasslands and some of the park's drier coniferous forests.
Date:
October 1, 2008
Creator:
Tuskan, Gerald A & Yin, Tongming
Object Type:
Report
System:
The UNT Digital Library
Symbolic visuals in advertising: The role of relevance.
Relevance has been applied to various conditions in the marketing literature but no single definition has been developed. A single clear definition will be helpful to researchers investigating relevance in the marketing and consumer behavior fields. Confusion also exists in the literature regarding to what extent a symbolic visual in an advertisement is relevant. Many researchers are also calling for empirical evidence of a linkage between relevance and response through a theoretical measure of relevance. The central theory used in this dissertation is Sperber and Wilson's (1995) theory of relevance (TOR). TOR can help researchers and marketing managers by explaining how consumers may interpret visuals in advertising. TOR explains why some visuals thought to be unconnected with the product become relevant in advertising. This study makes the assertion that TOR has been underutilized and even ignored by some researchers in past marketing literature. Thus, TOR is used to provide greater explanatory power of consumers' interpretation and response to advertising visuals than what is currently realized by researchers and marketing managers. A reliable measure of relevance was developed using TOR as a foundation. Experiments were conducted to empirically test TOR and support was found for most aspects of the theory. This …
Date:
August 2008
Creator:
Holmes, Gary R.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
[Funeral Program for Lori Gail Young, March 4, 2008]
Funeral program for Lori Gail Young, born January 9, 1959 and died February 29, 2008. The first funeral service was held March 4, 2008 at Victory Gospel Chapel. The second funeral service was held March 8, 2008 at East Saint Paul Baptist Church in Fort Worth, Texas, officiated by Reverend Carl W. Nealy. Funeral arrangements were made through Carter Taylor Williams Mortuary, and she was buried in Cedar Hill Memorial Park in Fort Worth, Texas.
Date:
March 4, 2008
Creator:
unknown
Object Type:
Pamphlet
System:
The Portal to Texas History
Jewish Herald-Voice (Houston, Tex.), Vol. 100, No. 25, Ed. 1 Thursday, September 25, 2008
Weekly Jewish newspaper from Houston, Texas that includes local, state and national news along with extensive advertising.
Date:
September 25, 2008
Creator:
Samuels, Jeanne F.
Object Type:
Newspaper
System:
The Portal to Texas History
Jewish Herald-Voice (Houston, Tex.), Vol. 100, No. 35, Ed. 1 Thursday, November 20, 2008
Weekly Jewish newspaper from Houston, Texas that includes local, state and national news along with extensive advertising.
Date:
November 20, 2008
Creator:
Samuels, Jeanne F.
Object Type:
Newspaper
System:
The Portal to Texas History
Jewish Herald-Voice (Houston, Tex.), Vol. 100, No. 31, Ed. 1 Thursday, October 30, 2008
Weekly Jewish newspaper from Houston, Texas that includes local, state and national news along with extensive advertising.
Date:
October 30, 2008
Creator:
Samuels, Jeanne F.
Object Type:
Newspaper
System:
The Portal to Texas History
Jewish Herald-Voice (Houston, Tex.), Vol. 100, No. 32, Ed. 1 Thursday, November 6, 2008
Weekly Jewish newspaper from Houston, Texas that includes local, state and national news along with extensive advertising.
Date:
November 6, 2008
Creator:
Samuels, Jeanne F.
Object Type:
Newspaper
System:
The Portal to Texas History