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Biomonitoring with Wireless Communications (open access)

Biomonitoring with Wireless Communications

This review is divided into three sections: technologies for monitoring physiological parameters; biosensors for chemical assays and wireless communications technologies including image transmissions. Applications range from monitoring high risk patients for heart, respiratory activity and falls to sensing levels of physical activity in military, rescue, and sports personnel. The range of measurements include, heart rate, pulse wave form, respiratory rate, blood oxygen, tissue pCO2, exhaled carbon dioxide and physical activity. Other feasible measurements will employ miniature chemical laboratories on silicon or plastic chips. The measurements can be extended to clinical chemical assays ranging from common blood assays to protein or specialized protein measurements (e.g., troponin, creatine, and cytokines such as TNF and IL6). Though the feasibility of using wireless technology to communicate vital signs has been demonstrated 32 years ago (1) it has been only recently that practical and portable devices and communications net works have become generally available for inexpensive deployment of comfortable and affordable devices and systems.
Date: March 1, 2003
Creator: Budinger, Thomas F.
System: The UNT Digital Library
Delamination Failure Investigation for Out-Of-Plane Loading in Laminates (open access)

Delamination Failure Investigation for Out-Of-Plane Loading in Laminates

In contrast to failure approaches at the lamina level or the micromechanics level the present work concerns failure characterization at the laminate level. Specifically, attention is given to the ultimate failure characterization for quasi-isotropic laminates. This is in further contrast to the commonly used approaches for initial damage or progressive damage. It is shown that the analytical failure forms decompose into two modes, one for out of plane, delamination type failure and one for in plane, fiber controlled type failure. The work here is mainly given over to the delamination mode of failure. Experimental results are presented for laminates in this mode of failure. These results are then integrated with the analytical forms to give a simple criterion for delamination failure.
Date: March 26, 2003
Creator: Christensen, R M & DeTeresa, S J
System: The UNT Digital Library
A Systematic Approach for the Evaluation of Technology Opportunities to Enhance the Proliferation Resistance of Civilian Nuclear Energy Systems (open access)

A Systematic Approach for the Evaluation of Technology Opportunities to Enhance the Proliferation Resistance of Civilian Nuclear Energy Systems

Enhancing the proliferation resistance of nuclear energy systems and fuel cycles is an ambitious undertaking. Current systems, dominated by the light water reactor fuel cycle are quite proliferation resistant. However, continued accumulations of plutonium in spent fuel and accumulations of separated plutonium resulting from reprocessing are eroding the proliferation resistance of today's nuclear energy systems. Alternatives to address these issues invariably involve making trade-offs among different proliferation risks and advantages. For example, thorium cycles reduce the quantity and quality of plutonium in spent fuel, but do so at the expense of increased fresh fuel enrichment and/or production of separable U233. Evaluation of these tradeoffs is difficult, as there are serious and significant differences of opinion regarding the relative merits and significance of the various risks of and barriers to proliferation from commercial nuclear power fuel cycles.
Date: March 10, 2003
Creator: Hassberger, J
System: The UNT Digital Library
Passive Seismic Monitoring for Rockfall at Yucca Mountain: Concept Tests (open access)

Passive Seismic Monitoring for Rockfall at Yucca Mountain: Concept Tests

For the purpose of proof-testing a system intended to remotely monitor rockfall inside a potential radioactive waste repository at Yucca Mountain, a system of seismic sub-arrays will be deployed and tested on the surface of the mountain. The goal is to identify and locate rockfall events remotely using automated data collecting and processing techniques. We install seismometers on the ground surface, generate seismic energy to simulate rockfall in underground space beneath the array, and interpret the surface response to discriminate and locate the event. Data will be analyzed using matched-field processing, a generalized beam forming method for localizing discrete signals. Software is being developed to facilitate the processing. To date, a three-component sub-array has been installed and successfully tested.
Date: March 3, 2003
Creator: Cheng, J.; Twilley, K.; Murvosh, H.; Tu, Y.; Luke, B.; Yfantis, A. et al.
System: The UNT Digital Library
Rates, Polarizations, and Asymmetries in Charmless Vector-Vector B Decays (open access)

Rates, Polarizations, and Asymmetries in Charmless Vector-Vector B Decays

With a sample of approximately 89 million B{bar B} pairs collected with the BABAR detector, they measure branching fractions, determine the degree of longitudinal polarization, and search for direct CP violation in the decays B{sup 0} {yields} {phi}K*{sup 0} and B{sup +} {yields} {phi}K*{sup +}. They perform a search for other charmless vector-vector B decays involving {rho} and K*(892) resonances and observe the decays B{sup +} {yields} {rho}{sup 0} K*{sup +} and B{sup +} {yields} {rho}{sup 0}{rho}{sup +}. The branching fractions are measured to be {Beta}({phi}K*{sup 0}) = (11.1{sub -1.2}{sup +1.3} {+-} 1.1) x 10{sup -6}, {Beta}({phi}K*{sup +}) = (12.1{sub -1.9}{sup +2.1} {+-} 1.5) x 10{sup -6}, {Beta}({rho}{sup 0} K*{sup +}) = (7.7{sub -2.0}{sup +2.1} {+-} 1.4) x 10{sup -6}, and {Beta}({rho}{sup 0}{rho}{sup +}) = (9.9{sub -2.5}{sup +2.6} {+-} 2.5) x 10{sup -6}. The longitudinal polarization fractions are measured to be {Lambda}{sub L}/{Lambda}({phi}K*{sup 0}) = 0.65 {+-} 0.07 {+-} 0.04 and {Lambda}{sub L}/{Lambda}({phi}K*{sup +}) = 0.46 {+-} 0.12 {+-} 0.05. They measure the charge asymmetries: {Alpha}{sub CP}({phi}K*{sup 0}) = +0.04 {+-} 0.12 {+-} 0.02 and {Alpha}{sub CP}({phi}K*{sup +}) = +0.16 {+-} 0.17 {+-} 0.04.
Date: March 11, 2003
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Gaillard, J.-M.; Hicheur, A.; Karyotakis, Y. et al.
System: The UNT Digital Library
Design and Performance of Capping Layers for EUV Multilayer Mirrors (open access)

Design and Performance of Capping Layers for EUV Multilayer Mirrors

The reflectance stability of multilayer coatings for extreme ultraviolet lithography (EUVL) in a commercial tool environment is of uttermost importance to ensure continuous exposures with minimum maintenance cost. We have made substantial progress in designing the protective capping layer coatings, understanding their performance and estimating their lifetimes based on accelerated electron beam and EUV exposure studies. Our current capping layer coatings have about 40 times longer lifetimes than Si-capped multilayer optics. Nevertheless, the lifetime of current Ru-capped multilayers is too short to satisfy commercial tool requirements and further improvements are essential.
Date: March 10, 2003
Creator: Bajt, S.; Chapman, H. N.; Nuygen, N.; Alameda, J.; Robinson, J. C.; Malinowski, M. et al.
System: The UNT Digital Library
Associated Higgs Boson Production With Heavy Quarks. (open access)

Associated Higgs Boson Production With Heavy Quarks.

The production of a Higgs boson in association with a pair of e quarks will play a very important role at both hadron and lepton colliders. We review the status of theoretical predictions and their relevance to Higgs boson studies, with particular emphasis on the recently calculated NLO QCD corrections to the inclusive cross section for p{bar p}, pp {yields} t{bar t}h. We conclude by briefly discussing the case of exclusive b{bar b}h production and the potential of this process in revealing signals of new physics beyond the Standard Model.
Date: March 15, 2003
Creator: Dawson, S.; Orr, L. H.; Reina, L. & Wackeroth, D.
System: The UNT Digital Library
Adaptive Optics Applications in Vision Science (open access)

Adaptive Optics Applications in Vision Science

Adaptive optics can be used to correct the aberrations in the human eye caused by imperfections in the cornea and the lens and thereby, improve image quality both looking into and out of the eye. Under the auspices of the NSF Center for Adaptive Optics and the DOE Biomedical Engineering Program, Lawrence Livermore National Laboratory has joined together with leading vision science researchers around the country to develop and test new ophthalmic imaging systems using novel wavefront corrector technologies. Results of preliminary comparative evaluations of these technologies in initial system tests show promise for future clinical utility.
Date: March 17, 2003
Creator: Olivier, S. S.
System: The UNT Digital Library
Systematics of Coupling Flows in AdS Backgrounds (open access)

Systematics of Coupling Flows in AdS Backgrounds

We give an effective field theory derivation, based on the running of Planck brane gauge correlators, of the large logarithms that arise in the predictions for low energy gauge couplings in compactified AdS}_5 backgrounds, including the one-loop effects of bulk scalars, fermions, and gauge bosons. In contrast to the case of charged scalars coupled to Abelian gauge fields that has been considered previously in the literature, the one-loop corrections are not dominated by a single 4D Kaluza-Klein mode. Nevertheless, in the case of gauge field loops, the amplitudes can be reorganized into a leading logarithmic contribution that is identical to the running in 4D non-Abelian gauge theory, and a term which is not logarithmically enhanced and is analogous to a two-loop effect in 4D. In a warped GUT model broken by the Higgs mechanism in the bulk,we show that the matching scale that appears in the large logarithms induced by the non-Abelian gauge fields is m_{XY}^2/k where m_{XY} is the bulk mass of the XY bosons and k is the AdS curvature. This is in contrast to the UV scale in the logarithmic contributions of scalars, which is simply the bulk mass m. Our results are summarized in a set …
Date: March 18, 2003
Creator: Goldberger, Walter D. & Rothstein, Ira Z.
System: The UNT Digital Library
The Confinement Problem in Lattice Gauge Theory (open access)

The Confinement Problem in Lattice Gauge Theory

I review investigations of the quark confinement mechanism that have been carried out in the framework of SU(N) lattice gauge theory. The special role of Z(N) center symmetry is emphasized.
Date: March 5, 2003
Creator: Greensite, J.
System: The UNT Digital Library
Proteins as paradigms of complex systems. (open access)

Proteins as paradigms of complex systems.

The science of complexity has moved to center stage within the past few decades. Complex systems range from glasses to the immune system and the brain. Glasses are too simple to possess all aspects of complexity; brains are too complex to expose common concepts and laws of complexity. Proteins, however, are systems where many concepts and laws of complexity can be explored experimentally, theoretically, and computationally. Such studies have elucidated crucial aspects. The energy landscape has emerged as one central concept; it describes the free energy of a system as a function of temperature and the coordinates of all relevant atoms. A second concept is that of fluctuations. Without fluctuations, proteins would be dead and life impossible. A third concept is slaving. Proteins are not isolated systems; they are embedded in cells and membranes. Slaving arises when the fluctuations in the surroundings of a protein dominate many of the motions of the protein proper.
Date: March 26, 2003
Creator: Fenimore, Paul W.; Frauenfelder, Hans & Young, Robert D.
System: The UNT Digital Library
Lightning, Downed Power Line Form Intriguing Rock Structure in Denton, Texas (open access)

Lightning, Downed Power Line Form Intriguing Rock Structure in Denton, Texas

This article describes a vitrified soil structure, formed by atmospheric and human activity, possessing characteristics of igneous and metamorphic rocks.
Date: March 2003
Creator: Hudak, Paul F. & Maxey, George
System: The UNT Digital Library
Further studies of electron avalanche gain in liquid argon (open access)

Further studies of electron avalanche gain in liquid argon

Previously we showed how small admixtures of xenon (Xe) stabilize electron avalanches in liquid Argon (LAr). In the present work, we have measured the positive charge carrier mobility in LAr with small admixtures of Xe to be 6.4 x 10{sup -3} cm{sup 2}/Vsec, in approximate agreement with the mobility measured in pure LAr, and consistent with holes as charge carriers. We have measured the concentration of Xe actually dissolved in the liquid and compared the results with expectations based on the amount of Xe gas added to the LAr. We also have tested LAr doped with krypton to investigate the mechanism of avalanche stabilization.
Date: March 7, 2003
Creator: Kim, J. G.; Dardin, S. M.; Kadel, R. W.; Kadyk, J. A.; Jackson, K. H.; Peskov, V. et al.
System: The UNT Digital Library
Comparative genomic analysis as a tool for biologicaldiscovery (open access)

Comparative genomic analysis as a tool for biologicaldiscovery

Biology is a discipline rooted in comparisons. Comparative physiology has assembled a detailed catalogue of the biological similarities and differences between species, revealing insights into how life has adapted to fill a wide-range of environmental niches. For example, the oxygen and carbon dioxide carrying capacity of vertebrate has evolved to provide strong advantages for species respiring at sea level, at high elevation or within water. Comparative- anatomy, -biochemistry, -pharmacology, -immunology and -cell biology have provided the fundamental paradigms from which each discipline has grown.
Date: March 30, 2003
Creator: Nobrega, Marcelo A. & Pennacchio, Len A.
System: The UNT Digital Library
Insights from Human/Mouse genome comparisons (open access)

Insights from Human/Mouse genome comparisons

Large-scale public genomic sequencing efforts have provided a wealth of vertebrate sequence data poised to provide insights into mammalian biology. These include deep genomic sequence coverage of human, mouse, rat, zebrafish, and two pufferfish (Fugu rubripes and Tetraodon nigroviridis) (Aparicio et al. 2002; Lander et al. 2001; Venter et al. 2001; Waterston et al. 2002). In addition, a high-priority has been placed on determining the genomic sequence of chimpanzee, dog, cow, frog, and chicken (Boguski 2002). While only recently available, whole genome sequence data have provided the unique opportunity to globally compare complete genome contents. Furthermore, the shared evolutionary ancestry of vertebrate species has allowed the development of comparative genomic approaches to identify ancient conserved sequences with functionality. Accordingly, this review focuses on the initial comparison of available mammalian genomes and describes various insights derived from such analysis.
Date: March 30, 2003
Creator: Pennacchio, Len A.
System: The UNT Digital Library
On the speed of gravity and the nu/c corrections to the Shapirotime delay (open access)

On the speed of gravity and the nu/c corrections to the Shapirotime delay

I compute the v/c correction to the gravitational time delayfor light passing by a massive object moving with speed v, and I finddisagreement with previously published results. It is also argued thatthe speed of gravity formula that was recently used in the conjunction ofJupiter and quasar J0842+1845 is frame dependent.
Date: March 26, 2003
Creator: Samuel, Stuart
System: The UNT Digital Library
Deutron photodissociation in ultraperipheral relativistic heavyion on deutron collisions (open access)

Deutron photodissociation in ultraperipheral relativistic heavyion on deutron collisions

In ultraperipheral relativistic deuteron on heavy-ion collisions, a photon emitted from the heavy nucleus may dissociate the deuterium ion. We find deuterium breakup cross sections of 1.24 barns for deuterium-gold collisions at a center of mass energy of 200 GeV per nucleon, as studied at the Relativistic Heavy Ion Collider, and 2.35 barns for deuterium-lead collisions at a center of mass energy of 6.2 TeV, as proposed for the Large Hadron Collider. In the latter case, the cross section is as large as that of hadronic interactions. The estimated error is 5%. We discuss the use of this process as a luminosity monitor and a 'tag' for moderate impact parameter collisions.
Date: March 24, 2003
Creator: Klein, Spencer & Vogt, Ramona
System: The UNT Digital Library
Synthesis of GaNxAs1-x thin films by pulsed laser melting andrapid thermal annealing (PLM-RTA) of N+-implanted GaAs (open access)

Synthesis of GaNxAs1-x thin films by pulsed laser melting andrapid thermal annealing (PLM-RTA) of N+-implanted GaAs

We present a systematic investigation on the formation of the highly mismatched alloy GaN{sub x}As{sub 1-x} using N{sup +}-implantation followed by a combination of pulsed laser melting and rapid thermal annealing. Thin films of GaN{sub x}As{sub 1-x} with x as high as 0.016 and an activation efficiency of the implanted N up to 50% have been synthesized with structural and optical properties comparable to films grown by epitaxial deposition techniques with similar substitutional N content. The effects of N{sup +} implantation dose, laser energy fluence and rapid thermal annealing temperature on the N incorporation as well as optical and structural properties of the GaN{sub x}As{sub 1-x} films are discussed.
Date: March 11, 2003
Creator: Yu, K. M.; Walukiewicz, W.; Scarpulla, M. A.; Dubon, O. D.; Wu, J.; Jasinski, J. et al.
System: The UNT Digital Library
Review of U.S. ESCO industry market trends: An empirical analysis of project data (open access)

Review of U.S. ESCO industry market trends: An empirical analysis of project data

This article summarizes a comprehensive empirical analysis of U.S. Energy Service Company (ESCO) industry trends and performance. We employ two parallel analytical approaches: a comprehensive survey of firms to estimate total industry size and a database of {approx}1500 ESCO projects, from which we report target markets and typical project characteristics, energy savings and customer economics. We estimate that industry investment for energy-efficiency related services reached US $2 billion in 2000 following a decade of strong growth. ESCO activity is concentrated in states with high economic activity and strong policy support. Typical projects save 150-200 MJ/m2/year and are cost-effective with median benefit/cost ratios of 1.6 and 2.1 for institutional and private sector projects. The median simple payback time is 7 years among institutional customers; 3 years is typical in the private sector. Reliance on DSM incentives has decreased since 1995. Preliminary evidence suggests that state enabling policies have boosted the industry in medium-sized states. ESCOs have proven resilient in the face of restructuring and will probably shift toward selling ''energy solutions,'' with energy efficiency part of a package. We conclude that a private sector energy-efficiency services industry that targets large commercial and industrial customers is viable and self-sustaining with appropriate policy …
Date: March 1, 2003
Creator: Goldman, Charles A.; Hopper, Nicole C.; Osborn, Julie G. & Singer, Terry E.
System: The UNT Digital Library
Inclusion complexes oriented in thermotropic liquid crystalline solvents studied with Carbon-13 NMR (open access)

Inclusion complexes oriented in thermotropic liquid crystalline solvents studied with Carbon-13 NMR

None
Date: March 28, 2003
Creator: Marjanska, Malgorzata; Goodson, Boyd M.; Castiglione, Franca & Pines, Alexander
System: The UNT Digital Library
A fast inversion method for interpreting borehole electromagnetic data (open access)

A fast inversion method for interpreting borehole electromagnetic data

None
Date: March 4, 2003
Creator: Kim, Hee Joon; Lee, Ki Ha & Wilt, Michael
System: The UNT Digital Library
Voluntary agreements in the industrial sector in China (open access)

Voluntary agreements in the industrial sector in China

China faces a significant challenge in the years ahead to continue to provide essential materials and products for a rapidly-growing economy while addressing pressing environmental concerns. China's industrial sector is heavily dependent on the country's abundant, yet polluting, coal resources. While tremendous energy conservation and environmental protection achievements were realized in the industrial sector in the past, there remains a great gulf between the China's level of energy efficiency and that of the advanced countries of the world. Internationally, significant energy efficiency improvement in the industrial sector has been realized in a number of countries using an innovative policy mechanism called Voluntary Agreements. This paper describes international experience with Voluntary Agreements in the industrial sector as well as the development of a pilot program to test the use of such agreements with two steel mills in Shandong Province, China.
Date: March 31, 2003
Creator: Price, Lynn; Worrell, Ernst & Sinton, Jonathan
System: The UNT Digital Library
Atmospheric Corrosion and Precipitation Runoff From Zinc and Zinc Alloys Surfaces (open access)

Atmospheric Corrosion and Precipitation Runoff From Zinc and Zinc Alloys Surfaces

The long-term atmospheric corrosion performance of rolled zinc and three thermal-sprayed (TS) zinc materials (Zn, Zn-15Al, and Al-12Zn-0.2In) was characterized by measuring corrosion product concentrations in precipitation runoff at coastal marine and inland sites. Corrosion rates and average zinc concentrations in the runoff were greater at the site having higher annual rainfall. Higher chloride concentrations did not seem to affect either the corrosion rates or the zinc concentrations in the runoff at the coastal site compared to those of the inland site. Zinc runoff concentrations were higher for TS Zn than rolled zinc due to the greater surface area of the thermal-sprayed surface. Average cumulative zinc runoff losses for the two sites were: 64 {micro}mol Zn/L for TS Zn, 37 {micro}mol Zn/L for rolled Zn, 24 {micro}mol Zn/L for TS Zn-15Al, and 1.8 {micro}mol Zn/L for TS Al-12Zn-0.2In. Cumulative zinc runoff losses were directly related both to the precipitation rate and to the availability of Zn in metal surfaces, a consequence of surface roughness and surface chemistry properties of the metal.
Date: March 16, 2003
Creator: Matthes, S. A.; Cramer, S. D.; Bullard, S. J.; Covino, B. S., Jr. & Holcomb, G. R.
System: The UNT Digital Library
Single spin asymmetries in semi-inclusive DIS at CLAS (open access)

Single spin asymmetries in semi-inclusive DIS at CLAS

None
Date: March 1, 2003
Creator: Hwang, D.S.
System: The UNT Digital Library