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DOD Personnel Clearances: Improved Annual Reporting Would Enable More Informed Congressional Oversight (open access)

DOD Personnel Clearances: Improved Annual Reporting Would Enable More Informed Congressional Oversight

A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Defense (DOD) industry personnel security clearance program has long-standing delays and backlogs in completing clearance requests and difficulties in accurately projecting its future needs for investigations to be conducted by the Office of Personnel Management (OPM). In 2006, Congress mandated that DOD report annually on the future requirements of the program and DOD's efforts to improve it, and that GAO evaluate DOD's first report. Specifically, GAO was required to report on (1) the extent to which the report responds to the issues in the mandate, (2) the number and cost of clearance investigations and adjudications in fiscal years 2000-2006, and (3) the extent to which DOD has developed procedures to estimate future needs, plans to reduce delays and backlogs, and plans to provide funding for the program. To accomplish these objectives, GAO obtained and reviewed laws, executive orders, policies, reports, and other documents related to the security clearance process and interviewed officials from a range of government offices concerned with the clearance process."
Date: February 13, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
DOD Personnel Clearances: DOD Faces Multiple Challenges in Its Efforts to Improve Clearance Processes for Industry Personnel (open access)

DOD Personnel Clearances: DOD Faces Multiple Challenges in Its Efforts to Improve Clearance Processes for Industry Personnel

Testimony issued by the Government Accountability Office with an abstract that begins "The Department of Defense (DOD) maintains approximately 2.5 million security clearances on servicemembers, federal DOD civilian employees, industry personnel for DOD and 23 other federal agencies, and employees in the legislative branch. Delays in determining eligibility for a clearance can heighten the risk that classified information will be disclosed to unauthorized sources, increase contract costs, and pose problems in attracting and retaining qualified personnel. In this statement, GAO addresses: (1) the status of DOD's efforts to improve its projections of the numbers of clearances needed for industry personnel, and (2) other long-standing challenges that have a negative effect on the efficiency and effectiveness of DOD's personnel security clearance program for industry personnel. This statement is based on a report GAO is issuing today (GAO-08-350) and other prior work, which included reviews of clearance-related documents and interviews of senior officials at DOD and the Office of Personnel Management (OPM)."
Date: February 13, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Information Technology: VA Has Taken Important Steps to Centralize Control of Its Resources, but Effectiveness Depends on Additional Planned Actions (open access)

Information Technology: VA Has Taken Important Steps to Centralize Control of Its Resources, but Effectiveness Depends on Additional Planned Actions

Testimony issued by the Government Accountability Office with an abstract that begins "The use of information technology (IT) is crucial to the Department of Veterans Affairs' (VA) mission to promote the health, welfare, and dignity of all veterans in recognition of their service to the nation. In this regard, the department's fiscal year 2009 budget proposal includes about $2.4 billion to support IT development, operations, and maintenance. VA has, however, experienced challenges in managing its IT projects and initiatives, including cost overruns, schedule slippages, and performance problems. In an effort to confront these challenges, the department is undertaking a realignment to centralize its IT management structure. This testimony summarizes the department's actions to realign its management structure to provide greater authority and accountability over its IT budget and resources and the impact of these actions to date. In developing this testimony, GAO reviewed previous work on the department's realignment and related budget issues, analyzed pertinent documentation, and interviewed VA officials to determine the current status and impact of the department's efforts to centralize the management of its IT budget and operations."
Date: February 13, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Department of Homeland Security: Progress Made in Implementation of Management and Mission Functions, but More Work Remains (open access)

Department of Homeland Security: Progress Made in Implementation of Management and Mission Functions, but More Work Remains

Testimony issued by the Government Accountability Office with an abstract that begins "The Department of Homeland Security (DHS) began operations in March 2003 with missions that include preventing terrorist attacks from occurring within the United States, reducing U.S. vulnerability to terrorism, minimizing damages from attacks that occur, and helping the nation recover from any attacks. GAO has reported that the implementation and transformation of DHS is an enormous management challenge and that the size, complexity, and importance of the effort make the challenge especially daunting and critical to the nation's security. GAO's prior work on mergers and acquisitions found that successful transformations of large organizations, even those faced with less strenuous reorganizations than DHS, can take at least 5 to 7 years to achieve. This testimony is based on GAO's August 2007 report evaluating DHS's progress between March 2003 and July 2007, selected reports issued since July 2007, and our institutional knowledge of homeland security issues."
Date: February 13, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Runway Safety: Progress on Reducing Runway Incursions Impeded by Leadership, Technology, and Other Challenges (open access)

Runway Safety: Progress on Reducing Runway Incursions Impeded by Leadership, Technology, and Other Challenges

Testimony issued by the Government Accountability Office with an abstract that begins "While aviation accidents in the United States are relatively infrequent, recent incidents have heightened concerns about safety on airport runways. As the nation's aviation system becomes more crowded every day, increased congestion at airports may exacerbate ground safety concerns. This statement discusses (1) the trends in runway incursions, (2) what FAA has done to improve runway safety, and (3) what more could be done. This statement is based on GAO's November 2007 report issued to this committee on runway safety. GAO's work on that report included surveying experts on the causes of runway incidents and accidents and the effectiveness of measures to address them, reviewing safety data, and interviewing agency and industry officials. This statement also contains information from FAA on recent incursions and actions taken since November 2007."
Date: February 13, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Three-dimensional lithographically-defined organotypic tissue arrays for quantitative analysis of morphogenesis and neoplastic progression (open access)

Three-dimensional lithographically-defined organotypic tissue arrays for quantitative analysis of morphogenesis and neoplastic progression

Here we describe a simple micromolding method to construct three-dimensional arrays of organotypic epithelial tissue structures that approximate in vivo histology. An elastomeric stamp containing an array of posts of defined geometry and spacing is used to mold microscale cavities into the surface of type I collagen gels. Epithelial cells are seeded into the cavities and covered with a second layer of collagen. The cells reorganize into hollow tissues corresponding to the geometry of the cavities. Patterned tissue arrays can be produced in 3-4 h and will undergo morphogenesis over the following one to three days. The protocol can easily be adapted to study a variety of tissues and aspects of normal and neoplastic development.
Date: February 13, 2008
Creator: Nelson, Celeste M.; Inman, Jamie L. & Bissell, Mina J.
Object Type: Article
System: The UNT Digital Library
Radiation monitoring with CVD Diamonds and PIN Diodes at BaBar (open access)

Radiation monitoring with CVD Diamonds and PIN Diodes at BaBar

The BaBar experiment at the Stanford Linear Accelerator Center has been using two polycrystalline chemical vapor deposition (pCVD) diamonds and 12 silicon PIN diodes for radiation monitoring and protection of the Silicon Vertex Tracker (SVT). We have used the pCVD diamonds for more than 3 years, and the PIN diodes for 7 years. We will describe the SVT and SVT radiation monitoring system as well as the operational difficulties and radiation damage effects on the PIN diodes and pCVD diamonds in a high-energy physics environment.
Date: February 13, 2008
Creator: Bruinsma, M.; Burchat, P.; Curry, S.; Edwards, A.J.; Kagan, H.; Kass, R. et al.
Object Type: Article
System: The UNT Digital Library
Colloid Science of Metal Nanoparticle Catalysts in 2D and 3D Structures. Challenges of Nucleation, Growth, Composition, Particle Shape, Size Control and their Influence on Activity and Selectivity (open access)

Colloid Science of Metal Nanoparticle Catalysts in 2D and 3D Structures. Challenges of Nucleation, Growth, Composition, Particle Shape, Size Control and their Influence on Activity and Selectivity

Recent breakthroughs in synthesis in nanosciences have achieved control of size and shapes of nanoparticles that are relevant for catalyst design. In this article, we review the advance of synthesis of nanoparticles, fabrication of two and three dimensional model catalyst system, characterization, and studies of activity and selectivity. The ability to synthesize monodispersed platinum and rhodium nanoparticles in the 1-10 nm range permitted us to study the influence of composition, structure, and dynamic properties of monodispersed metal nanoparticle on chemical reactivity and selectivity. We review the importance of size and shape of nanoparticles to determine the reaction selectivity in multi-path reactions. The influence of metal-support interaction has been studied by probing the hot electron flows through the metal-oxide interface in catalytic nanodiodes. Novel designs of nanoparticle catalytic systems are discussed.
Date: February 13, 2008
Creator: Somorjai, Gabor A. & Park, Jeong Y.
Object Type: Article
System: The UNT Digital Library
REFINEMENT OF THE NEPHELINE DISCRIMINATOR: RESULTS OF A PHASE I STUDY (open access)

REFINEMENT OF THE NEPHELINE DISCRIMINATOR: RESULTS OF A PHASE I STUDY

The performance of a glass used for immobilization of high-level nuclear waste (HLW) is generally quantified by its resistance to chemical degradation, or durability. The durability of a HLW glass is dependent on its composition. If crystalline phases form within a glass during cooling, the composition of the residual glass network is altered, therefore affecting the durability of the glass. Crystallization of nepheline (NaAlSiO{sub 4}) has been shown to adversely impact the durability of HLW glasses since it removes glass forming species (in this case, Al and Si) from the glass network. The propensity for nepheline crystallization in a HLW glass increases with increasing concentrations of Al{sub 2}O{sub 3} and Na{sub 2}O in the glass. Nepheline crystallization is therefore of concern for processing of HLW at the Defense Waste Processing Facility (DWPF) since the sludge waste streams at the Savannah River Site (SRS) can contain high concentrations of Al{sub 2}O{sub 3} and Na{sub 2}O. Currently, a 'nepheline discriminator' is included as a process control constraint at the DWPF. The nepheline discriminator relates the concentrations of SiO{sub 2}, Na{sub 2}O and Al{sub 2}O{sub 3} (as weight percentages in glass) to a critical value of 0.62. The discriminator defines a boundary line …
Date: February 13, 2008
Creator: Fox, K; James Newell, J; Tommy Edwards, T; David Best, D; Irene Reamer, I & Phyllis Workman, P
Object Type: Report
System: The UNT Digital Library
Mechanisms of disease: epithelial-mesenchymal transition and back again: does cellular plasticity fuel neoplastic progression? (open access)

Mechanisms of disease: epithelial-mesenchymal transition and back again: does cellular plasticity fuel neoplastic progression?

Epithelial-mesenchymal transition (EMT) is a conversion that facilitates organ morphogenesis and tissue remodeling in physiological processes such as embryonic development and wound healing. A similar phenotypic conversion is also detected in fibrotic diseases and neoplasia, which is associated with disease progression. EMT in cancer epithelial cells often seems to be an incomplete and bi-directional process. In this Review, we discuss the phenomenon of EMT as it pertains to tumor development, focusing on exceptions to the commonly held rule that EMT promotes invasion and metastasis. We also highlight the role of the RAS-controlled signaling mediators, ERK1, ERK2 and PI3-kinase, as microenvironmental responsive regulators of EMT.
Date: February 13, 2008
Creator: Bissell, Mina J; Turley, Eva A.; Veiseh, Mandana; Radisky, Derek C. & Bissell, Mina J.
Object Type: Article
System: The UNT Digital Library
Prompt gamma activation analysis (PGAA) and short-lived neutron activation analysis (NAA) applied to the characterization of legacy materials (open access)

Prompt gamma activation analysis (PGAA) and short-lived neutron activation analysis (NAA) applied to the characterization of legacy materials

Without quality historical records that provide the composition of legacy materials, the elemental and/or chemical characterization of such materials requires a manual analytical strategy that may expose the analyst to unknown toxicological hazards. In addition, much of the existing legacy inventory also incorporates radioactivity, and, although radiological composition may be determined by various nuclear-analytical methods, most importantly, gamma-spectroscopy, current methods of chemical characterization still require direct sample manipulation, thereby presenting special problems with broad implications for both the analyst and the environment. Alternately, prompt gamma activation analysis (PGAA) provides a'single-shot' in-situ, non-destructive method that provides a complete assay of all major entrained elemental constituents.1-3. Additionally, neutron activation analysis (NAA) using short-lived activation products complements PGAA and is especially useful when NAA activation surpasses the PGAA in elemental sensitivity.
Date: February 13, 2008
Creator: Firestone, Richard B; English, G. A.; Firestone, R. B.; Perry, D. L.; Reijonen, J. P.; Leung, Ka-Ngo et al.
Object Type: Article
System: The UNT Digital Library
Recent Developments in Impact and Application to Future Light Sources (open access)

Recent Developments in Impact and Application to Future Light Sources

This paper discusses two recently added capabilities of the IMPACT suite that are relevant to modeling electron linacs, namely the new 1D coherent synchrotron radiation (CSR) modeling capability and the integrated Green's function (IFG) algorithm for modeling high aspect ratio beams. In addition, we present initial results of application of the enhanced version of IMPACT-Z to high-fidelity modeling of the microbunching instability in a realistic light source lattice.
Date: February 13, 2008
Creator: Pogorelov, I.; Qiang, J.; Ryne, R.; Venturini, M.; Zholents, A. & Warnock, R.
Object Type: Article
System: The UNT Digital Library
Action-Oriented Benchmarking: Concepts and Tools (open access)

Action-Oriented Benchmarking: Concepts and Tools

Most energy benchmarking tools provide static feedback on how one building compares to a larger set of loosely similar buildings, without providing information at the end-use level or on what can be done to reduce consumption, cost, or emissions. In this article--Part 1 of a two-part series--we describe an 'action-oriented benchmarking' approach, which extends whole-building energy benchmarking to include analysis of system and component energy use metrics and features. Action-oriented benchmarking thereby allows users to generate more meaningful metrics and to identify, screen and prioritize potential efficiency improvements. This opportunity assessment process can then be used to inform and optimize a full-scale audit or commissioning process. We introduce a new web-based action-oriented benchmarking system and associated software tool-EnergyIQ. The benchmarking methods, visualizations, and user interface design are informed by an end-user needs assessment survey and best-practice guidelines from ASHRAE.
Date: February 13, 2008
Creator: Commission, California Energy; Mathew, Paul; Mills, Evan; Mathew, Paul; Piette, Mary Ann; Bourassa, Norman et al.
Object Type: Article
System: The UNT Digital Library
Evaluation of optical imaging and spectroscopy approaches for cardiac tissue depth assessment (open access)

Evaluation of optical imaging and spectroscopy approaches for cardiac tissue depth assessment

NIR light scattering from ex vivo porcine cardiac tissue was investigated to understand how imaging or point measurement approaches may assist development of methods for tissue depth assessment. Our results indicate an increase of average image intensity as thickness increases up to approximately 2 mm. In a dual fiber spectroscopy configuration, sensitivity up to approximately 3 mm with an increase to 6 mm when spectral ratio between selected wavelengths was obtained. Preliminary Monte Carlo results provided reasonable fit to the experimental data.
Date: February 13, 2008
Creator: Lin, B; Matthews, D; Chernomordik, V; Gandjbakhche, A; Lane, S & Demos, S G
Object Type: Article
System: The UNT Digital Library
Constraining Cosmic Evolution of Type Ia Supernovae (open access)

Constraining Cosmic Evolution of Type Ia Supernovae

We present the first large-scale effort of creating composite spectra of high-redshift type Ia supernovae (SNe Ia) and comparing them to low-redshift counterparts. Through the ESSENCE project, we have obtained 107 spectra of 88 high-redshift SNe Ia with excellent light-curve information. In addition, we have obtained 397 spectra of low-redshift SNe through a multiple-decade effort at Lick and Keck Observatories, and we have used 45 ultraviolet spectra obtained by HST/IUE. The low-redshift spectra act as a control sample when comparing to the ESSENCE spectra. In all instances, the ESSENCE and Lick composite spectra appear very similar. The addition of galaxy light to the Lick composite spectra allows a nearly perfect match of the overall spectral-energy distribution with the ESSENCE composite spectra, indicating that the high-redshift SNe are more contaminated with host-galaxy light than their low-redshift counterparts. This is caused by observing objects at all redshifts with similar slit widths, which corresponds to different projected distances. After correcting for the galaxy-light contamination, subtle differences in the spectra remain. We have estimated the systematic errors when using current spectral templates for K-corrections to be {approx}0.02 mag. The variance in the composite spectra give an estimate of the intrinsic variance in low-redshift maximum-light …
Date: February 13, 2008
Creator: Foley, Ryan J.; Filippenko, Alexei V.; Aguilera, C.; Becker, A. C.; Blondin, S.; Challis, P. et al.
Object Type: Article
System: The UNT Digital Library
Microaspiration for high-pressure freezing: a new method for ultrastructural preservation of fragile and sparse tissues for TEM and electron tomography (open access)

Microaspiration for high-pressure freezing: a new method for ultrastructural preservation of fragile and sparse tissues for TEM and electron tomography

High-pressure freezing is the preferred method to prepare thick biological specimens for ultrastructural studies. However, the advantages obtained by this method often prove unattainable for samples that are difficult to handle during the freezing and substitution protocols. Delicate and sparse samples are difficult to manipulate and maintain intact throughout the sequence of freezing, infiltration, embedding, and final orientation for sectioning and subsequent TEM imaging. An established approach to surmount these difficulties is the use of cellulose microdialysis tubing to transport the sample. With an inner diameter of 200 micrometers, the tubing protects small and fragile samples within the thickness constraints of high-pressure freezing, and the tube ends can be sealed to avoid loss of sample. Importantly, the transparency of the tubing allows optical study of the specimen at different steps in the process. Here, we describe the use of a micromanipulator and microinjection apparatus to handle and position delicate specimens within the tubing. We report two biologically significant examples that benefit from this approach, 3D cultures of mammary epithelial cells and cochlear outer hair cells. We illustrate the potential for correlative light and electron microscopy as well as electron tomography.
Date: February 13, 2008
Creator: Auer, Manfred; Triffo, W. J.; Palsdottir, H.; McDonald, K. L.; Inman, J. L.; Bissell, M. J. et al.
Object Type: Article
System: The UNT Digital Library
Hosing Instability in the Blow-Out Regime for Plasma-Wakefield Acceleration (open access)

Hosing Instability in the Blow-Out Regime for Plasma-Wakefield Acceleration

The electron hosing instability in the blow-out regime of plasma-wakefield acceleration is investigated using a linear perturbation theory about the electron blow-out trajectory in Lu et al. [in Phys. Rev. Lett. 96, 165002 (2006)]. The growth of the instability is found to be affected by the beam parameters unlike in the standard theory Whittum et al. [Phys. Rev. Lett. 67, 991 (1991)] which is strictly valid for preformed channels. Particle-in-cell simulations agree with this new theory, which predicts less hosing growth than found by the hosing theory of Whittum et al.
Date: February 13, 2008
Creator: Huang, C.; Lu, W.; Zhou, M.; Clayton, C. E.; Joshi, C.; Mori, W.B. et al.
Object Type: Article
System: The UNT Digital Library
System-level line-edge roughness limits in extreme ultraviolet lithography (open access)

System-level line-edge roughness limits in extreme ultraviolet lithography

As critical dimensions shrink, line edge and width roughness (LER and LWR) become of increasing concern. Traditionally LER is viewed as a resist-limited effect; however, as critical dimensions shrink and LER requirements become proportionally more stringent, system-level effects begin to play an important role. Recent advanced EUV resist testing results have demonstrated lower bounds on achievable LER at the level of approximately 2 to 3 nm. Here we use modeling to demonstrate that a significant portion of this low bound may in fact be do to system-level effects and in particular the mask. Of concern are both LER on the mask as well as roughness of the multilayer reflector. Modeling also shows roughness (flare) in the projection optics not to be of concern.
Date: February 13, 2008
Creator: Jones, Juanita; Naulleau, Patrick P; Niakoula, Dimitra & Zhang, Guojing
Object Type: Article
System: The UNT Digital Library
Beam Dynamics Challenges for the ILC (open access)

Beam Dynamics Challenges for the ILC

The International Linear Collider (ILC) is a proposal for 500 GeV center-of-mass electron-positron collider, with a possible upgrade to {approx}1 TeV center-of-mass. At the heart of the ILC are the two {approx}12 km 1.3 GHz superconducting RF (SCRF) linacs which will accelerate the electron and positron beams to an initial maximum energy of 250 GeV each. The Global Design Effort (GDE)--responsible for the world-wide coordination of this uniquely international project--published the ILC Reference Design Report in August of 2007 [1]. The ILC outlined in the RDR design stands on a legacy of over fifteen-years of R&D. The GDE is currently beginning the next step in this ambitious project, namely an Engineering Design phase, which will culminate with the publication of an Engineering Design Report (EDR) in mid-2010. Throughout the history of linear collider development, beam dynamics has played an essential role. In particular, the need for complex computer simulations to predict the performance of the machine has always been crucial, not least because the parameters of the ILC represent in general a large extrapolation from where current machines operate today; many of the critical beam-dynamics features planned for the ILC can ultimately only be truly tested once the ILC has …
Date: February 13, 2008
Creator: Kubo, Kiyoshi; /KEK, Tsukuba; Seryi, Andrei; /SLAC; Walker, Nicholas; /DESY et al.
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 39, No. 18, Ed. 1 Wednesday, February 13, 2008 (open access)

Greensheet (Houston, Tex.), Vol. 39, No. 18, Ed. 1 Wednesday, February 13, 2008

Free weekly newspaper that includes business and classified advertising.
Date: February 13, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Cherokeean Herald (Rusk, Tex.), Vol. 158, No. 51, Ed. 1 Wednesday, February 13, 2008 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 158, No. 51, Ed. 1 Wednesday, February 13, 2008

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: February 13, 2008
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 91, No. 18, Ed. 1 Wednesday, February 13, 2008 (open access)

North Texas Daily (Denton, Tex.), Vol. 91, No. 18, Ed. 1 Wednesday, February 13, 2008

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: February 13, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Rambler (Fort Worth, Tex.), Vol. 100, No. 3, Ed. 1 Wednesday, February 13, 2008 (open access)

The Rambler (Fort Worth, Tex.), Vol. 100, No. 3, Ed. 1 Wednesday, February 13, 2008

Weekly student newspaper from Texas Wesleyan University in Fort Worth, Texas that includes campus and local news along with advertising.
Date: February 13, 2008
Creator: Poling, Shawn R.
Object Type: Newspaper
System: The Portal to Texas History
Texas Attorney General Opinion: GA-0602 (open access)

Texas Attorney General Opinion: GA-0602

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification: Whether, under Local Government Code chapter 334, Terrell County may borrow money to construct an approved venue project, to be repaid from the venue project fund.
Date: February 13, 2008
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History