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Targeting the tumor microenvironment

Description: Despite some notable successes cancer remains, for the most part, a seemingly intractable problem. There is, however, a growing appreciation that targeting the tumor epithelium in isolation is not sufficient as there is an intricate mutually sustaining synergy between the tumor epithelial cells and their surrounding stroma. As the details of this dialogue emerge, new therapeutic targets have been proposed. The FDA has already approved drugs targeting microenvironmental components such as VEGF and aromatase and many more agents are in the pipeline. In this article, we describe some of the 'druggable' targets and processes within the tumor microenvironment and review the approaches being taken to disrupt these interactions.
Date: November 7, 2006
Creator: Kenny, P.A.; Lee, G.Y. & Bissell, M.J.
Partner: UNT Libraries Government Documents Department

Time Resolved Shadowgraph Images of Silicon during Laser Ablation:Shockwaves and Particle Generation

Description: Time resolved shadowgraph images were recorded of shockwaves and particle ejection from silicon during laser ablation. Particle ejection and expansion were correlated to an internal shockwave resonating between the shockwave front and the target surface. The number of particles ablated increased with laser energy and was related to the crater volume.
Date: May 6, 2006
Creator: Liu, C.Y.; Mao, X.L.; Greif, R. & Russo, R.E.
Partner: UNT Libraries Government Documents Department

Analysis of interaction phenomena between liquid jets and materials. Revision 1

Description: The interaction phenomena of high-velocity liquid jets impinging on a material surface have been investigated theoretically and experimentally to understand the physics of material removal by jet-machining processes. Experiments were performed to delineate conditions under which liquid jet impacts will cause mass removal, and to determine optimum jet-cutting conditions. Theoretical analyses have also been carried out to study the effects of multiple jet-droplet impacts on a target surface as a material deformation mechanism. The calculated target response and spallation behavior following droplet impacts and their physical implications are also discussed.
Date: April 1, 1995
Creator: Kang, S.W.; Reitter, T. & Carlson, G.
Partner: UNT Libraries Government Documents Department

Overcoming Thermal Shock Problems in Liquid Targets

Description: Short pulse accelerator-driven neutron sources such as the Spallation Neutron Source (SNS) employ high-energy proton beam energy deposition in heavy metal (such as mercury) over microsecond time frames. The interaction of the energetic proton beam with the mercury target leads to very high heating rates in the target. Although the resulting temperature rise is relatively small (a few {degree}C ), the rate of temperature rise is enormous ({approximately}10{sup 7} C/s) during the very brief beam pulse ({approximately}0.58 {micro}s). The resulting thermal-shock induced compression of the mercury leads to the production of large amplitude pressure waves in the mercury that interact with the walls of the mercury target and the bulk flow field. Safety-related operational concerns exist in two main areas, viz., (1) possible target enclosure failure from impact of thermal shocks on the wall due to its direct heating from the proton beam and the loads transferred from the mercury compression waves, and (2) impact of the compression-cum-rarefaction wave-induced effects such as cavitation bubble emanation and fluid surging. Preliminary stress evaluations indicate stress levels approaching yielding conditions and beyond in select regions of the target. Also, the induction of cavitation (which could assist in attenuation) can also release gases that may accumulate at undesirable locations and impair heat transfer.
Date: June 2000
Creator: Taleyarkhan, R. P. & Kim, S. H.
Partner: UNT Libraries Government Documents Department

Hydraulic testing of APT blanket assemblies

Description: The Thermal Fluids Laboratory (TFL) conducted hydraulic tests on two versions of the test samples of the Low Flux Blanket Assembly and on four High Flux Blanket Assemblies in support of the Area-A Tests to be conducted at Los Alamos National Laboratory (LANL). The first purpose for the tests was to check for manufacturing flaws that might have constricted cooling passages. No evidence of manufacturing flaws was found. The second purpose was to provide hydraulic information that could be used to calculate orifice sizes for limiting flow to the assemblies after installation. During the TFL hydraulic tests differential pressures were measured for the six pieces of hardware as functions of water flowrate. In all cases differential pressure was proportional to flowrate squared. The particular functional relationships needed by LANL are listed in graphical and tabular form.
Date: May 1, 1996
Creator: Steimke, J.L.
Partner: UNT Libraries Government Documents Department

Support Facility for a Graphite Target Neutrino Factory

Description: The Target Support Facility for a Neutrino Producing Research Facility extends from the pretarget, primary beam focusing region to the end of the decay channel. Technical components include the target, beam absorber, and solenoid magnetic-field focusing system. While the ultimate goal is to target about 4 MW of proton beam in the target area., smaller values and different target materials (e.g., low Z) are considered to facilitate the first step. As detailed in this report, a carbon target was chosen with an incident primary beam power of 1.5 MW, The target is embedded in a high-field solenoid magnet of 20 T, followed by a transition section channel, where the field tapers down to 1.25 T. An iterative design process has been carried out which optimizes Monte Carlo code flux projections with realistic magnetic-field parameters. The severe radiation environment and component shielding requirements strongly influence design choices. The overall system design includes the capture and decay channel solenoids, the design parameters of which were provided by the National High Magnetic Field Laboratory. This design balances resistive and superconducting magnet contributions. Facility requirements, including shielding, remote handling, radioactive water system, etc. are based on the final design goal of 4 MW. The extent of the Target Support Facility and radiation-handling equipment includes the 50-m decay channel, where remote-handling operations are also required.
Date: August 1, 2000
Creator: Spampinato, P.T.; Chesser, J.B.; Gabriel, T.A.; Gallmeier, F.X.; Haines, J.R.; Lillie, R.A. et al.
Partner: UNT Libraries Government Documents Department

SELEX RICH performance and physics results

Description: SELEX took data in the 1996/7 Fixed Target Run at Fermilab. The excellent performance parameters of the SELEX RICH Detector had direct influence on the quality of the obtained physics results.
Date: August 28, 2002
Creator: al., Jurgen Engelfried et
Partner: UNT Libraries Government Documents Department

The future of fixed target physics: Snowmass E5 working group summary

Description: Fixed target experimentation remains a vigorous and important tool. In many cases it provides the best technique to study elementary physics. Here the authors explore several areas, where, in the near future, fixed target experiments have the potential to alter the understanding of physics. These include, but are clearly not limited to, high precision tests of CP violation in the Kaon sector, ultra-precise determination of the weak mixing angle and its evolution, and lepton flavor violation.
Date: December 10, 2002
Creator: al., Krishna Kumar et
Partner: UNT Libraries Government Documents Department

Slip stacking

Description: We have started beam studies for ''slip stacking''[1] in the Main Injector in order to increase proton intensity on a target for anti-proton production. It has been verified that the system for slip stacking is working with low intensity beam. For a high intensity operation, we are developing a feedback[2][3] and feedforward system.
Date: September 19, 2002
Creator: Steimel, Kiyomi Koba and James
Partner: UNT Libraries Government Documents Department

HUD PowerSaver Pilot Loan Program

Description: The U.S. Department of Housing and Urban Development (HUD) recently announced the creation of a pilot loan program for home energy improvements. The PowerSaver loan program is a new, energy-focused variant of the Title I Property Improvement Loan Insurance Program (Title I Program) and is planned for introduction in early 2011. The PowerSaver pilot will provide lender insurance for secured and unsecured loans up to $25,000 to single family homeowners. These loans will specifically target residential energy efficiency and renewable energy improvements. HUD estimates the two-year pilot will fund approximately 24,000 loans worth up to $300 million; the program is not capped. The Federal Housing Administration (FHA), HUD's mortgage insurance unit, will provide up to $25 million in grants as incentives to participating lenders. FHA is seeking lenders in communities with existing programs for promoting residential energy upgrades.
Date: December 10, 2010
Creator: Zimring, Mark & Hoffman, Ian
Partner: UNT Libraries Government Documents Department

Target Detection in SAR Images Based on a Level Set Approach

Description: This paper introduces a new framework for point target detection in synthetic aperture radar (SAR) images. We focus on the task of locating reflective small regions using alevel set based algorithm. Unlike most of the approaches in image segmentation, we address an algorithm which incorporates speckle statistics instead of empirical parameters and also discards speckle filtering. The curve evolves according to speckle statistics, initially propagating with a maximum upward velocity in homogeneous areas. Our approach is validated by a series of tests on synthetic and real SAR images and compared with three other segmentation algorithms, demonstrating that it configures a novel and efficient method for target detection purpose.
Date: September 1, 2008
Creator: Marques, Regis C.P.; Medeiros, Fatima N.S. & Ushizima, Daniela M.
Partner: UNT Libraries Government Documents Department

Measurements of MeV photon flashes in petawatt laser experiments

Description: Planar targets illuminated by the Petawatt laser system emit directed beams of photons with energies of MeVs. The laser pulses have durations of 0.5 or 5 psec, on target energies in excess of 100 joules, and focal-spot sizes that vary from 10 to 100 µm, producing peak intensities greater than 10<sup>19</sup> watts/cm<sup>;2</sup>. Arrays of PIN diodes, dosimeters and nuclear-activation detectors measure the angular distributions of photons with energies greater than 0.5 MeV. The PIN diodes, with 1 cm<sup>2</sup> by 500-µm sensitive volume, are housed in lead pigs with 2.5-cm thick walls. Measured emission intensities have been as high as 5x10<sup>13</sup> (gamma) MeV/steradian. The angular distributions are highly directed in forward directions, with significant variations on a shot-to-shot basis. Backward radiated intensities tend to be more than a decade lower than in forward direct
Date: November 10, 1998
Creator: Phillips, T.; Brown, C. G.; Cowan, T.; Hatchett, S.; Hunt, A.; Key, M. et al.
Partner: UNT Libraries Government Documents Department

Energetic Proton Generation in Ultra-Intense Laser-Solid Interactions

Description: An explanation for the energetic ions observed in the PetaWatt experiments is presented. In solid target experiments with focused intensities exceeding 10{sup 20} W/cm{sup 2}, high-energy electron generation, hard bremsstrahlung, and energetic protons have been observed on the backside of the target. In this report, we attempt to explain the physical process present that will explain the presence of these energetic protons, as well as explain the number, energy, and angular spread of the protons observed in experiment. In particular, we hypothesize that hot electrons produced on the front of the target are sent through to the back off the target, where they ionize the hydrogen layer there. These ions are then accelerated by the hot electron cloud, to tens of MeV energies in distances of order tens of microns, whereupon they end up being detected in the radiographic and spectrographic detectors.
Date: March 1, 2000
Creator: Wilks, S.C.; Langdon, A.B.; Cowan, T.E.; Roth, M.; Singh, M.; Hatchett, S. et al.
Partner: UNT Libraries Government Documents Department

Measurement Strategies for Remote Sensing Applications

Description: Remote sensing has grown to encompass many instruments and observations, with concomitant data from a huge number of targets. As evidenced by the impressive growth in the number of published papers and presentations in this field, there is a great deal of interest in applying these capabilities. The true challenge is to transition from directly observed data sets to obtaining meaningful and robust information about remotely sensed targets. We use physics-based end-to-end modeling and analysis techniques as a framework for such a transition. Our technique starts with quantified observables and signatures of a target. The signatures are propagated through representative atmospheres to realistically modeled sensors. Simulated data are then propagated through analysis routines, yielding measurements that are directly compared to the original target attributes. We use this approach to develop measurement strategies which ensure that our efforts provide a balanced approach to obtaining substantive information on our targets.
Date: March 6, 1999
Creator: Weber, P.G.; Theiler, J.; Smith, B.; Love, S.P.; LaDelfe, P.C.; Cooke, B.J. et al.
Partner: UNT Libraries Government Documents Department

Momentum Transfer by Laser Ablation of Irregularly Shaped Space Debris

Description: Proposals for ground-based laser remediation of space debris rely on the creation of appropriately directed ablation-driven impulses to either divert the fragment or drive it into an orbit with a perigee allowing atmospheric capture. For a spherical fragment, the ablation impulse is a function of the orbital parameters and the laser engagement angle. If, however, the target is irregularly shaped and arbitrarily oriented, new impulse effects come into play. Here we present an analysis of some of these effects.
Date: February 4, 2010
Creator: Liedahl, D A; Libby, S B & Rubenchik, A
Partner: UNT Libraries Government Documents Department

Deep Levels in p- and n-type InGaAsN for High Efficiency Multi-Junction III-V Solar Cells

Description: Red Teaming is an advanced form of assessment that can be used to identify weaknesses in a variety of cyber systems. it is especially beneficial when the target system is still in development when designers can readily affect improvements. This paper discusses the red team analysis process and the author's experiences applying this process to five selected Information Technology Office (ITO) projects. Some detail of the overall methodology, summary results from the five projects, and lessons learned are contained within this paper.
Date: November 11, 1999
Creator: ALLERMAN,ANDREW A.; JONES,ERIC D.; KAPLAR,ROBERT J.; KURTZ,STEVEN R.; KWON,DAEWON & RINGEL,STEVEN A.
Partner: UNT Libraries Government Documents Department

Enhanced Processing for a Towed Array Using an Optimal Noise Canceling Approach

Description: Noise self-generated by a surface ship towing an array in search of a weak target presents a major problem for the signal processing especially if broadband techniques are being employed. In this paper we discuss the development and application of an adaptive noise canceling processor capable of extracting the weak far-field acoustic target in a noisy ocean acoustic environment. The fundamental idea for this processor is to use a model-based approach incorporating both target and ship noise. Here we briefly describe the underlying theory and then demonstrate through simulation how effective the canceller and target enhancer perform. The adaptivity of the processor not only enables the ''tracking'' of the canceller coefficients, but also the estimation of target parameters for localization. This approach which is termed ''joint'' cancellation and enhancement produces the optimal estimate of both in a minimum (error) variance sense.
Date: July 21, 2005
Creator: Sullivan, E J & Candy, J V
Partner: UNT Libraries Government Documents Department

Environmental Management System (EMS) objectives and targets : annual results summary - FY2011.

Description: Sandia National Laboratories/New Mexico's (SNL/NM) Environmental Management System is the integrated approach for members of the workforce to identify and manage environmental risks. Each Fiscal Year (FY) SNL/NM performs an analysis to identify environmental aspects, and the environmental programs associated with them are charged with the task of routinely monitoring and measuring the objectives and targets that are established to mitigate potential impacts of SNL/NM's operations on the environment. An annual summary of the results achieved towards meeting established objectives and targets provides a connection to, and rational for, annually revised environmental aspects. The purpose of this document is to summarize the results achieved and documented in FY2011.
Date: February 1, 2012
Creator: Vetter, Douglas Walter
Partner: UNT Libraries Government Documents Department

ISOTOPE PRODUCTION CROSS SECTIONS FROM THE FRAGMENTATION OF 16O AND 12C AT RELATIVISTIC ENERGIES

Description: The 0-degree fragmentation products of {sup 16}O and {sup 12}C at 2.1-GeV/n and {sup 12}C at 1.05-GeV/n have been measured for targets ranging from H to Pb. They present a total of 464 partial-production cross sections for 35 isotopes. The cross sections are energy independent and can be factored into beam-fragment and target terms. The target factor, {gamma}{sub T} = A{sub T}{sup 1/4}, and other evidence, imply the isotopes are produced in peripheral interactions.
Date: February 1, 1975
Creator: Lindstrom, P.J.; Greiner, D.E.; Heckman, H.H.; Cork, Bruce & Bieser, F.S.
Partner: UNT Libraries Government Documents Department

Modeling the Office of Science Ten Year Facilities Plan: The PERI Architecture Tiger Team

Description: The Performance Engineering Institute (PERI) originally proposed a tiger team activity as a mechanism to target significant effort optimizing key Office of Science applications, a model that was successfully realized with the assistance of two JOULE metric teams. However, the Office of Science requested a new focus beginning in 2008: assistance in forming its ten year facilities plan. To meet this request, PERI formed the Architecture Tiger Team, which is modeling the performance of key science applications on future architectures, with S3D, FLASH and GTC chosen as the first application targets. In this activity, we have measured the performance of these applications on current systems in order to understand their baseline performance and to ensure that our modeling activity focuses on the right versions and inputs of the applications. We have applied a variety of modeling techniques to anticipate the performance of these applications on a range of anticipated systems. While our initial findings predict that Office of Science applications will continue to perform well on future machines from major hardware vendors, we have also encountered several areas in which we must extend our modeling techniques in order to fulfill our mission accurately and completely. In addition, we anticipate that models of a wider range of applications will reveal critical differences between expected future systems, thus providing guidance for future Office of Science procurement decisions, and will enable DOE applications to exploit machines in future facilities fully.
Date: June 26, 2009
Creator: de Supinski, Bronis R.; Alam, Sadaf; Bailey, David H.; Carrington, Laura; Daley, Chris; Dubey, Anshu et al.
Partner: UNT Libraries Government Documents Department