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Evolution of Primary Hemostasis in Early Vertebrates (open access)

Evolution of Primary Hemostasis in Early Vertebrates

Article on the evolution of primary hemostasis in early vertebrates.
Date: December 23, 2009
Creator: Kim, Seongcheol; Carrillo, Maira; Kulkarni, Vrinda & Jagadeeswaran, Pudur
System: The UNT Digital Library
Quantum Irreversibility and Chaos [Phys. Rev. Lett. 67, 2593 (1991)] (open access)

Quantum Irreversibility and Chaos [Phys. Rev. Lett. 67, 2593 (1991)]

Corrections to an equation printed with a typographical error in Quantum Irreversibility and Chaos, Physical Review Letters 67, 2593 (1991).
Date: December 23, 1991
Creator: Bonci, Luca; Roncaglia, Roberto; West, Bruce J. & Grigolini, Paolo
System: The UNT Digital Library
Physical limits for high ion charge states in pulsed discharges in vacuum (open access)

Physical limits for high ion charge states in pulsed discharges in vacuum

Short-pulse, high-current discharges in vacuum were investigated with the goal to maximize the ion charge state number. In a direct extension of previous work [Appl. Phys. Lett. 92, 041502 (2008)], the role of pulse length, rate of current rise, and current amplitude was studied. For all experimental conditions, the usable (extractable) mean ion charge state could not be pushed beyond 7+. Instead, a maximum of the mean ion charge state (about 6+ to 7+ for most cathode materials) was found for a power of 2-3 MW dissipated in the discharge gap. The maximum is the result of two opposing processes that occur when the power is increased: (i) the formation of higher ion charge states, and (ii) a greater production of neutrals (both metal and non-metal), which reduces the charge state via charge exchange collisions.
Date: December 23, 2008
Creator: Yushkov, Georgy & Anders, Andre
System: The UNT Digital Library
Liquid-drop technique for generation of organic glass and metal shells (open access)

Liquid-drop technique for generation of organic glass and metal shells

We have for several years utilized the technique of capillary wave synchronization of the break-up of single and multiple component jets to produce uniform sized liquid drops and solid particles, and hollow liquid and solid shells. The technique has also been used to encapsulate a number of liquids in impermeable spherical shells. Highly uniform glass shells have been made by generating uniform drops of glass forming materials in an aqueous solution, subsequently evaporating the water, and then fusing and blowing the remaining solids in a high temperature vertical tube furnace. Experimental results will be presented and the critical problems in further research in this field will be discussed.
Date: December 23, 1981
Creator: Hendricks, C.D.
System: The UNT Digital Library
Overview of spin physics (open access)

Overview of spin physics

Spin physics activities at medium and high energies became significantly active when polarized targets and polarized beams became accessible for hadron-hadron scattering experiments. My overview of spin physics will be inclined to the study of strong interaction using facilities at Argonne ZGS, Brookhaven AGS (including RHIC), CERN, Fermilab, LAMPF, an SATURNE. In 1960 accelerator physicists had already been convinced that the ZGS could be unique in accelerating a polarized beam; polarized beams were being accelerated through linear accelerators elsewhere at that time. However, there was much concern about going ahead with the construction of a polarized beam because (i) the source intensity was not high enough to accelerate in the accelerator, (ii) the use of the accelerator would be limited to only polarized-beam physics, that is, proton-proton interaction, and (iii) p-p elastic scattering was not the most popular topic in high-energy physics. In fact, within spin physics, [pi]-nucleon physics looked attractive, since the determination of spin and parity of possible [pi]p resonances attracted much attention. To proceed we needed more data beside total cross sections and elastic differential cross sections; measurements of polarization and other parameters were urgently needed. Polarization measurements had traditionally been performed by analyzing the spin of …
Date: December 23, 1992
Creator: Yokosawa, A.
System: The UNT Digital Library
Winter experience of a passive solar retrofit. Final technical report (open access)

Winter experience of a passive solar retrofit. Final technical report

An older home in St. Louis had 2 inch foam insulation added to the outside of masonry walls with stucco exterior finish applied. The south wall was modified so that there is a gross solar collection area of 26.2 m/sup 2/, with 13.2 m/sup 2/ of greenhouse, 8.6 m/sup 2/ of direct gain and 4.4 m/sup 2/ of Trombe components. The performance of the building and its data acquisition system are described. (MHR)
Date: December 23, 1980
Creator: Michels, T. I. & Andes, F. S.
System: The UNT Digital Library
Progress on achieving the ICF conditions needed for high gain (open access)

Progress on achieving the ICF conditions needed for high gain

Progress during the past two years has moved us much closer to demonstrating the scientific and technological requirements for high gain ICF in the laboratory. This progress has been made possible by operating at the third harmonic of 1..mu..m light which dramatically reduces concern about hot electrons and by advances in diagnostics such as 100 ps x-ray framing cameras which greatly increase the data available from each experiment. Making use of many of these new capabilities, major improvements in confinement conditions have been achieved for ICF implosions. In particular, in an optimized hohlraum on Nova, radiation driven implosions with convergence ratio in excess of 30 (volume compression /approximately/3 /times/ 10/sup 4/) have performed essentially as predicted by spherical implosion calculations. This paper presents these results as well as examples of advances in several other areas and discusses the implications for the future of ICF with lasers and heavy ion beam drivers. 8 refs., 10 figs.
Date: December 23, 1988
Creator: Lindl, J.D.
System: The UNT Digital Library
High Performance Fortran: An overview (open access)

High Performance Fortran: An overview

The purpose of this paper is to give an overview of the work of the High Performance Fortran Forum (HPFF). This group of industry, academic, and user representatives has been meeting to define a set of extensions for Fortran dedicated to the special problems posed by a very high performance computers, especially the new generation of parallel computers. The paper describes the HPFF effort and its goals and gives a brief description of the functionality of High Performance Fortran (HPF).
Date: December 23, 1992
Creator: Zosel, M. E.
System: The UNT Digital Library
Comparison of Three Afterglow Morphologies (open access)

Comparison of Three Afterglow Morphologies

Herein we compare three functional families for afterglow morphologies: the homogeneous afterglow with constant shock surface energy density, the structured afterglow for which the energy density decays as a power-law as a function of viewer angle, and the gaussian afterglow which has an exponential decay of energy density with viewer angle. We simulate observed lightcurves and polarization curves for each as seen from a variety of observer vantage points. We find that the homogeneous jet is likely inconsistent with observations and suggest that the future debate on the structure of afterglow jets will be between the other two candidates.
Date: December 23, 2003
Creator: Salmonson, J D; Rossi, E & Lazzati, D
System: The UNT Digital Library
POPULATION KINETICS MODELING FOR NON-LTE AND NON-MAXWELLIAN PLASMAS GENERATED IN FINITE TEMPERATURE DENSE MATTER EXPERIMENTS ARISING FROM SHORT PULSE X-RAY SOURCE (open access)

POPULATION KINETICS MODELING FOR NON-LTE AND NON-MAXWELLIAN PLASMAS GENERATED IN FINITE TEMPERATURE DENSE MATTER EXPERIMENTS ARISING FROM SHORT PULSE X-RAY SOURCE

The short pulse x-ray sources will provide a major advance in dense matter studies important to understand implosion physics for ICF as a generator of warm dense matter or a probe of finite temperature dense matter. The interaction of such a high-energy photon pulse with the initially solid matter creates highly transient states of plasmas initially whose relaxation processes are of interest to the equation of states or spectral properties of these matter. For these plasmas, assumptions such as LTE population distributions or Maxwellian electron energy distributions should be tested by employing a method that does not make these assumption a priori. Our goal is to present a model that can be used to simulate the electron distributions, the ionization balance and the spectral output of transient systems generated in the future ICF experiments. We report on the progress in developing a non-LTE atomic population kinetics code integrated with Boltzmann equation solver to provide a self-consistent time-dependent solution of the level populations and the particle energy distributions.
Date: December 23, 2003
Creator: Chung, H; Lee, R W & Morgan, W L
System: The UNT Digital Library
Climate change and forests in India: note from the guest editors (open access)

Climate change and forests in India: note from the guest editors

Forestry is one of the most important sectors in the context of climate change. It lies at the center-stage of global mitigation and adaptation efforts. Yet, it is one of the least understood sectors, especially in tropical zones, which constitute a significant portion of the global forests. Recently, there has been a growing interest in forests in addressing global climate change. The IPCC Assessment Report 4 (2007) Chapters related to forests have highlighted the limited number of studies on the impact of climate change on forests at the regional, national and sub-national level, while policy makers need information at these scales. Further, implication of projected climate change on mitigation potential of forest sector is only briefly mentioned in the IPCC report, with limited literature to support the conclusions. India is one among the top ten nations in the world in terms of forest cover. It is also sixth among the tropical countries in terms of forested area. As IPCC Assessment Report 5 work is about to be initiated soon, studies on the impact of climate change on forests as well as the mitigation potential of the forest sector, particularly at regional and national level, will be of great interest to …
Date: December 23, 2010
Creator: Ravindtranath, N.H. & Aaheim, Asbjporn
System: The UNT Digital Library
X-ray streak and framing camera techniques (open access)

X-ray streak and framing camera techniques

This paper reviews recent developments and applications of ultrafast diagnostic techniques for x-ray measurements. These techniques, based on applications of image converter devices, are already capable of significantly important resolution capabilities. Techniques capable of time resolution in the sub-nanosecond regime are being considered. Mechanical cameras are excluded from considerations as are devices using phosphors or fluors as x-ray converters.
Date: December 23, 1975
Creator: Coleman, L. W. & Attwood, D. T.
System: The UNT Digital Library
Reactions of the CN Radical with Benzene and Toluene: Product Detection and Low-Temperature Kinetics (open access)

Reactions of the CN Radical with Benzene and Toluene: Product Detection and Low-Temperature Kinetics

Low temperature rate coefficients are measured for the CN + benzene and CN + toluene reactions using the pulsed Laval nozzle expansion technique coupled with laser-induced fluorescence detection. The CN + benzene reaction rate coefficient at 105, 165 and 295 K is found to be relatively constant over this temperature range, 3.9 - 4.9 x 10-10 cm3 molecule-1 s-1. These rapid kinetics, along with the observed negligible temperature dependence, are consistent with a barrierless reaction entrance channel and reaction efficiencies approaching unity. The CN + toluene reaction is measured to have a slower rate coefficient of 1.3 x 10-10 cm3 molecule-1 s-1 at 105 K. At room temperature, non-exponential decay profiles are observed for this reaction that may suggest significant back-dissociation of intermediate complexes. In separate experiments, the products of these reactions are probed at room temperature using synchrotron VUV photoionization mass spectrometry. For CN + benzene, cyanobenzene (C6H5CN) is the only product recorded with no detectable evidence for a C6H5 + HCN product channel. In the case of CN + toluene, cyanotoluene (NCC6H4CH3) constitutes the only detected product. It is not possible to differentiate among the ortho, meta and para isomers of cyanotoluene because of their similar ionization energies …
Date: December 23, 2009
Creator: Trevitt, Adam J.; Goulay, Fabien; Taatjes, Craig A.; Osborn, David L. & Leone, Stephen R.
System: The UNT Digital Library
Continuity and Performance in Composite Electrodes (open access)

Continuity and Performance in Composite Electrodes

It is shown that the rate performance of a lithium battery composite electrode may be compromised by poor internal connectivity due to defects and inhomogeneities introduced during electrode fabrication or subsequent handling. Application of a thin conductive coating to the top surface of the electrode or to the separator surface in contact with the electrode improves the performance by providing alternative current paths to partially isolated particles of electroactive material. Mechanistic implications are discussed and strategies for improvement in electrode design and fabrication are presented.
Date: December 23, 2009
Creator: Chen, Guoying & Richardson, Thomas J.
System: The UNT Digital Library
1-D Van der Waals Foams Heated by Ion Beam Energy Deposition (open access)

1-D Van der Waals Foams Heated by Ion Beam Energy Deposition

One dimensional simulations of various initial average density aluminum foams (modeled as slabs of solid metal separated by low density regions) heated by volumetric energy deposition are conducted with a Lagrangian hydrodynamics code using a van der Waals equation of tate (EOS). The resulting behavior is studied to facilitate the design of future warm dense matter (WDM) experiments at LBNL. In the simulations the energy deposition ranges from 10 to 30 kJ/g and from 0.075 to 4.0 ns total pulse length, resulting in temperatures from approximately 1 o 4 eV. We study peak pressures and temperatures in the foams, expansion velocity, and the phase evolution. Five relevant time scales in the problem are identified. Additionally, we present a method for characterizing the level of inhomogeneity in a foam target as it is heated and the time it takes for a foam to homogenize.
Date: December 23, 2009
Creator: Zylstra, A. B.; Barnard, J. J. & More, R. M.
System: The UNT Digital Library
Triangulation Made Easy (open access)

Triangulation Made Easy

We describe a simple and efficient algorithm for two-view triangulation of 3D points from approximate 2D matches based on minimizing the L2 reprojection error. Our iterative algorithm improves on the one by Kanatani et al. by ensuring that in each iteration the epipolar constraint is satisfied. In the case where the two cameras are pointed in the same direction, the method provably converges to an optimal solution in exactly two iterations. For more general camera poses, two iterations are sufficient to achieve convergence to machine precision, which we exploit to devise a fast, non-iterative method. The resulting algorithm amounts to little more than solving a quadratic equation, and involves a fixed, small number of simple matrixvector operations and no conditional branches. We demonstrate that the method computes solutions that agree to very high precision with those of Hartley and Sturm's original polynomial method, though achieves higher numerical stability and 1-4 orders of magnitude greater speed.
Date: December 23, 2009
Creator: Lindstrom, P.
System: The UNT Digital Library
Tissue architecture and function: dynamic reciprocity via extra- and intra-cellular matrices (open access)

Tissue architecture and function: dynamic reciprocity via extra- and intra-cellular matrices

Mammary gland development, functional differentiation, and homeostasis are orchestrated and sustained by a balance of biochemical and biophysical cues from the organ's microenvironment. The three-dimensional microenvironment of the mammary gland, predominantly 'encoded' by a collaboration between the extracellular matrix (ECM), hormones, and growth factors, sends signals from ECM receptors through the cytoskeletal intracellular matrix to nuclear and chromatin structures resulting in gene expression; the ECM in turn is regulated and remodeled by signals from the nucleus. In this chapter, we discuss how coordinated ECM deposition and remodeling is necessary for mammary gland development, how the ECM provides structural and biochemical cues necessary for tissue-specific function, and the role of the cytoskeleton in mediating the extra - to intracellular dialogue occurring between the nucleus and the microenvironment. When operating normally, the cytoskeletal-mediated dynamic and reciprocal integration of tissue architecture and function directs mammary gland development, tissue polarity, and ultimately, tissue-specific gene expression. Cancer occurs when these dynamic interactions go awry for an extended time.
Date: December 23, 2008
Creator: Xu, Ren; Boudreau, Aaron & Bissell, Mina J
System: The UNT Digital Library
Role for DNA methylation in the regulation of miR-200c and miR-141 expression in normal and cancer cells (open access)

Role for DNA methylation in the regulation of miR-200c and miR-141 expression in normal and cancer cells

BACKGROUND: The microRNA-200 family participates in the maintenance of an epithelial phenotype and loss of its expression can result in epithelial to mesenchymal transition (EMT). Furthermore, the loss of expression of miR-200 family members is linked to an aggressive cancer phenotype. Regulation of the miR-200 family expression in normal and cancer cells is not fully understood. METHODOLOGY/ PRINCIPAL FINDINGS: Epigenetic mechanisms participate in the control of miR-200c and miR-141 expression in both normal and cancer cells. A CpG island near the predicted mir-200c/mir-141 transcription start site shows a striking correlation between miR-200c and miR-141 expression and DNA methylation in both normal and cancer cells, as determined by MassARRAY technology. The CpG island is unmethylated in human miR-200/miR-141 expressing epithelial cells and in miR-200c/miR-141 positive tumor cells. The CpG island is heavily methylated in human miR-200c/miR-141 negative fibroblasts and miR-200c/miR-141 negative tumor cells. Mouse cells show a similar inverse correlation between DNA methylation and miR-200c expression. Enrichment of permissive histone modifications, H3 acetylation and H3K4 trimethylation, is seen in normal miR-200c/miR-141-positive epithelial cells, as determined by chromatin immunoprecipitation coupled to real-time PCR. In contrast, repressive H3K9 dimethylation marks are present in normal miR-200c/miR-141-negative fibroblasts and miR-200c/miR-141 negative cancer cells and the …
Date: December 23, 2009
Creator: Vrba, Lukas; Jensen, Taylor J.; Garbe, James C.; Heimark, Ronald L.; Cress, Anne E.; Dickinson, Sally et al.
System: The UNT Digital Library
Laser conditioning methods of Hafnia Silica multilayer mirrors (open access)

Laser conditioning methods of Hafnia Silica multilayer mirrors

None
Date: December 23, 1999
Creator: Hue, J; Maricle, S M; Schwartz, S; Sheehan, L M & Stolz, C J
System: The UNT Digital Library
Role of starting material composition in interfacial damage morphology of Hafnia Silica multilayer coatings (open access)

Role of starting material composition in interfacial damage morphology of Hafnia Silica multilayer coatings

None
Date: December 23, 1999
Creator: Bevis, R P; Stolz, C J; Von Gunten, M K; Weakley, S C & Wu, Z L
System: The UNT Digital Library
B physics: measurement of the j/psi meson and b-hadron production cross sections in p anti-p collisions at s**(1/2) = 1960 gev (open access)

B physics: measurement of the j/psi meson and b-hadron production cross sections in p anti-p collisions at s**(1/2) = 1960 gev

The authors present a new measurement of the inclusive and differential production cross sections of J/{psi} mesons and b-hadrons in proton-antiproton collisions at {radical}s = 1960 GeV. The data correspond to an integrated luminosity of 39.7 pb{sup -1} collected by the CDF Run II detector. They find the integrated cross section for inclusive J/{psi} production for all transverse momenta from 0 to 20 GeV/c in the rapidity range |y| < 0.6 to be 4.08 {+-} 0.02(stat){sub -0.33}{sup +0.36}(syst) {mu}b. They separate the fraction of J/{psi} events from the decay of the long-lived b-hadrons using the lifetime distribution in all events with p{sub T}(J/{psi}) > 1.25 GeV/c. They find the total cross section for b-hadrons, including both hadrons and anti-hadrons, decaying to J/{psi} with transverse momenta greater than 1.25 GeV/c in the rapidity range |y(J/{psi})| < 0.6, is 0.330 {+-} 0.005(stat){sub -0.033}{sup +0.036}(syst) {mu}b. Using a Monte Carlo simulation of the decay kinematics of b-hadrons to all final states containing a J/{psi}, they extract the first measurement of the total single b-hadron cross section down to zero transverse momentum at {radical}s = 1960 GeV. They find the total single b-hadron cross section integrated over all transverse momenta for b-hadrons in the …
Date: December 23, 2004
Creator: Acosta, D.
System: The UNT Digital Library
What ignites optical jets? (open access)

What ignites optical jets?

The properties of radio galaxies and quasars with and without optical or X-ray jets are compared. The majority of jets from which high-frequency emission has been detected so far (13 with optical emission, 11 with X-rays, 13 with both) are associated with the most powerful radio sources at any given redshift. It is found that optical/X-ray jet sources are more strongly beamed than the average population of extragalactic radio sources. This suggests that the detection or non-detection of optical emission from jets has so far been dominated by surface brightness selection effects, not by jet physics. It implies that optical jets are much more common than is currently appreciated.
Date: December 23, 2002
Creator: Jester, Sebastian
System: The UNT Digital Library
Neutrino factories: Physics potential (open access)

Neutrino factories: Physics potential

The physics potential of low-performance and high-performance neutrino factories is briefly reviewed.
Date: December 23, 2003
Creator: Geer, Steve
System: The UNT Digital Library
Electroweak symmetry breaking by strong dynamics and the collider phenomenology (open access)

Electroweak symmetry breaking by strong dynamics and the collider phenomenology

We discuss the possible signatures in the electroweak symmetry breaking sector by new strong dynamics at future hadron colliders such as the Tevatron upgrade, the LHC and VLHC, and e{sup +}e{sup -} linear colliders. Examples include a heavy Higgs-like scalar resonance, a heavy Technicolor-like vector resonance and pseudo-Goldstone states, non-resonance signatures via enhanced gauge-boson scattering and fermion compositeness.
Date: December 23, 2002
Creator: al., Timothy L. Barklow et
System: The UNT Digital Library