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IN-VIVO DIAGNOSIS OF CHEMICALLY INDUCED MELANOMA IN AN ANIMAL MODEL USING UV-VISIBLE AND NIR ELASTIC SCATTERING SPECTROSCOPY: PRELIMINARY TESTING. (open access)

IN-VIVO DIAGNOSIS OF CHEMICALLY INDUCED MELANOMA IN AN ANIMAL MODEL USING UV-VISIBLE AND NIR ELASTIC SCATTERING SPECTROSCOPY: PRELIMINARY TESTING.

Elastic light scattering spectroscopy (ESS) has the potential to provide spectra that contain both morphological and chromophore information from tissue. We report on a preliminary study of this technique, with the hope of developing a method for diagnosis of highly-pigmented skin lesions, commonly associated with skin cancer. Four opossums were treated with dimethylbenz(a)anthracene to induce both malignant melanoma and benign pigmented lesions. Skin lesions were examined in vivo using both UV-visible and near infrared (NIR) ESS, with wavelength ranges of 330-900 nm and 900-1700 nm, respectively. Both portable systems used identical fiber-optic probe geometry throughout all of the measurements. The core diameters for illuminating and collecting fibers were 400 and 200 {micro}m, respectively, with center-to-center separation of 350 {micro}m. The probe was placed in optical contact with the tissue under investigation. Biopsies from lesions were analyzed by two standard histopathological procedures. Taking into account only the biopsied lesions, UV-visible ESS showed distinct spectral correlation for 11/13 lesions. The NIR-ESS correlated well with 12/13 lesions correctly. The results of these experiments showed that UV-visible and NIR-ESS have the potential to classify benign and malignant skin lesions, with encouraging agreement to that provided by standard histopathological examination. These initial results show potential …
Date: January 1, 2001
Creator: A'AMAR, C.; LEY, R. & AL, ET
Object Type: Article
System: The UNT Digital Library
Buffer Chemical Polishing and RF Testing of the 56 MHz SRF Cavity (open access)

Buffer Chemical Polishing and RF Testing of the 56 MHz SRF Cavity

N/A
Date: January 1, 2009
Creator: A., Burrill
Object Type: Report
System: The UNT Digital Library
IBS and Potential Luminosity Improvement for RHIC Operation Below Transition Energy (open access)

IBS and Potential Luminosity Improvement for RHIC Operation Below Transition Energy

N/A
Date: January 1, 2009
Creator: A., Fedotov
Object Type: Report
System: The UNT Digital Library
Plasma Micro-Stability Analysis for the RHIC Electron Beam Cooler (open access)

Plasma Micro-Stability Analysis for the RHIC Electron Beam Cooler

N/A
Date: January 1, 2004
Creator: A., Hershcovitch
Object Type: Report
System: The UNT Digital Library
Monte Carlo simulations of phosphate polyhedron connectivity in glasses (open access)

Monte Carlo simulations of phosphate polyhedron connectivity in glasses

Monte Carlo simulations of phosphate tetrahedron connectivity distributions in alkali and alkaline earth phosphate glasses are reported. By utilizing a discrete bond model, the distribution of next-nearest neighbor connectivities between phosphate polyhedron for random, alternating and clustering bonding scenarios was evaluated as a function of the relative bond energy difference. The simulated distributions are compared to experimentally observed connectivities reported for solid-state two-dimensional exchange and double-quantum NMR experiments of phosphate glasses. These Monte Carlo simulations demonstrate that the polyhedron connectivity is best described by a random distribution in lithium phosphate and calcium phosphate glasses.
Date: January 1, 2000
Creator: ALAM,TODD M.
Object Type: Report
System: The UNT Digital Library
Laser Safety and Hazard Analysis for the Trailer (B70) Based AURA Laser System (open access)

Laser Safety and Hazard Analysis for the Trailer (B70) Based AURA Laser System

A laser safety and hazard analysis was performed for the AURA laser system based on the 2000 version of the American National Standards Institute's (ANSI) Standard Z136.1, for ''Safe Use of Lasers'' and the 2000 version of the ANSI Standard Z136.6, for ''Safe Use of Lasers Outdoors''. The trailer based AURA laser system is a mobile platform, which is used to perform laser interaction experiments and tests at various national test sites. The trailer (B70) based AURA laser system is generally operated on the United State Air Force Starfire Optical Range (SOR) at Kirtland Air Force Base (KAFB), New Mexico. The laser is used to perform laser interaction testing inside the laser trailer as well as outside the trailer at target sites located at various distances from the exit telescope. In order to protect personnel, who work inside the Nominal Hazard Zone (NHZ), from hazardous laser emission exposures it was necessary to determine the Maximum Permissible Exposure (MPE) for each laser wavelength (wavelength bands) and calculate the appropriate minimum Optical Density (OD{sub min}) of the laser safety eyewear used by authorized personnel and the Nominal Ocular Hazard Distance (NOHD) to protect unauthorized personnel who may have violated the boundaries of …
Date: January 1, 2003
Creator: AUGUSTONI, ARNOLD L.
Object Type: Report
System: The UNT Digital Library
Laser Safety and Hazardous Analysis for the ARES (Big Sky) Laser System (open access)

Laser Safety and Hazardous Analysis for the ARES (Big Sky) Laser System

A laser safety and hazard analysis was performed for the ARES laser system based on the 2000 version of the American National Standards Institute's (ANSI) Standard Z136.1,for Safe Use of Lasers and the 2000 version of the ANSI Standard Z136.6, for Safe Use of Lasers Outdoors. The ARES laser system is a Van/Truck based mobile platform, which is used to perform laser interaction experiments and tests at various national test sites.
Date: January 1, 2003
Creator: AUGUSTONI, ARNOLD L.
Object Type: Report
System: The UNT Digital Library
Domestic Energy Scenarios (open access)

Domestic Energy Scenarios

This report attempts to organize and evaluate scenarios of markets and technologies that could impact renewable and distributed electricity-generating technologies during the next 20-100 years in the United States. For the purposes of this report, scenarios are defined broadly as any projection or forecast that helps illuminate the potential of Renewable Electric Technologies (RETs) in the United States. Scenarios vary widely in terms of their scope-some focus on supply of fuels or narrow segments of markets with limited timeframes, while others are broader in scope and time span. There are several factors that influence the market penetration of renewable energy and distributed generation technologies. Most notable among these are natural gas prices, technology improvements, and policy measures. Natural gas prices are important because most new generating capacity, as well as marginal generation units, generally are natural-gas fired. Assumptions about the rate of improvement in renewable and distributed generation technologies can also have a significant impact on market penetration. Finally, policy measures that support these technologies, such as tax credits or interconnection standards, can contribute to their accelerated adoption.
Date: January 1, 2003
Creator: Aabakken, J. & Short, W.
Object Type: Report
System: The UNT Digital Library
Measurement of the $\ttbar$ Production Cross Section in 2 fb$^{-1}$ of $\ppbar$ Collisions at $\sqrt{s}=1.96$ TeV Using Lepton Plus Jets Events with Soft Muon b-Tagging (open access)

Measurement of the $\ttbar$ Production Cross Section in 2 fb$^{-1}$ of $\ppbar$ Collisions at $\sqrt{s}=1.96$ TeV Using Lepton Plus Jets Events with Soft Muon b-Tagging

We present a measurement of the t{bar t} production cross section in p{bar p} collisions at {radical}s = 1.96 TeV using events containing a high transverse momentum electron or muon, three or more jets, and missing transverse energy. Events consistent with t{bar t} decay are found by identifying jets containing candidate heavy-flavor semileptonic decays to muons. The measurement uses a CDF Run II data sample corresponding to 2 fb{sup -1} of integrated luminosity. Based on 248 candidate events with three or more jets and an expected background of 79.5 {+-} 5.3 events, we measure a production cross section of 9.1 {+-} 1.6 pb.
Date: January 1, 2009
Creator: Aaltonen, T.
Object Type: Article
System: The UNT Digital Library
First Measurement of ZZ Production in panti-p Collisions at s**(1/2) = 1.96-TeV (open access)

First Measurement of ZZ Production in panti-p Collisions at s**(1/2) = 1.96-TeV

We report the first measurement of the cross section for Z boson pair production at a hadron collider. This result is based on a data sample corresponding to 1.9 fb{sup -1} of integrated luminosity from p{bar p} collisions at {radical}s = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. In the {ell}{ell}{ell}{prime}{ell}{prime} channel, we observe three ZZ candidates with an expected background of 0.096{sub -0.063}{sup +0.092} events. In the {ell}{ell}{nu}{nu} channel, we use a leading-order calculation of the relative ZZ and WW event probabilities to discriminate between signal and background. In the combination of {ell}{ell}{ell}{prime}{ell}{prime} and {ell}{ell}{nu}{nu} channels, we observe an excess of events with a probability of 5.1 x 10{sup -6} to be due to the expected background. This corresponds to a significance of 4.4 standard deviations. The measured cross section is {sigma}(p{bar p} {yields}ZZ) = 1.4{sub -0.6}{sup +0.7} (stat.+syst.) pb, consistent with the standard model expectation.
Date: January 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, M. G.; Alvarez Gonzalez, B.; Amerio, S. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of Ratios of Fragmentation Fractions for Bottom Hadrons in p anti-p Collisions at s**(1/2) = 1.96-TeV (open access)

Measurement of Ratios of Fragmentation Fractions for Bottom Hadrons in p anti-p Collisions at s**(1/2) = 1.96-TeV

None
Date: January 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, M. G.; Alvarez Gonzalez, B.; Amerio, S. et al.
Object Type: Article
System: The UNT Digital Library
Search for Heavy Top-like Quarks Using Lepton Plus Jets Events in 1.96-TeV p anti-p Collisions (open access)

Search for Heavy Top-like Quarks Using Lepton Plus Jets Events in 1.96-TeV p anti-p Collisions

None
Date: January 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, M. G.; Alvarez Gonzalez, B.; Amerio, S. et al.
Object Type: Article
System: The UNT Digital Library
Search for New Heavy Particles Decaying to Z0 Z0 ---> eeee in p - anti-p Collisions at s**(1/2) = 1.96-TeV (open access)

Search for New Heavy Particles Decaying to Z0 Z0 ---> eeee in p - anti-p Collisions at s**(1/2) = 1.96-TeV

We report the results of a search for the anomalous production of a massive particle decaying to four electrons via two Z{sup 0} bosons in 1.1 fb{sup -1} of p{bar p} collisions at {radical}s =1.96 TeV collected by the CDF II detector at Fermilab. We employ optimized electron identification criteria to maximize acceptance and efficiency. We estimate the backgrounds in the invariant mass range 500-1000 GeV/c{sup 2} to be 0.028 {+-} 0.009 (stat) {+-} 0.011 (syst) events. We observe zero events in this search region. Assuming a Randall-Sundrum graviton production model, we set 95% CL limits on {sigma} x BF(G {yields} Z{sup 0}Z{sup 0}) < 4-6 pb, depending on the graviton mass.
Date: January 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, M.G.; Alvarez Gonzalez, B.; Amerio, S. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the top quark mass at CDF using the `neutrino phi weighting' template method on a lepton plus isolated track sample (open access)

Measurement of the top quark mass at CDF using the `neutrino phi weighting' template method on a lepton plus isolated track sample

We present a measurement of the top quark mass with t{bar t} dilepton events produced in p{bar p} collisions at the Fermilab Tevatron ({radical}s = 1.96 TeV) and collected by the CDF II detector. A sample of 328 events with a charged electron or muon and an isolated track, corresponding to an integrated luminosity of 2.9 fb{sup -1}, are selected as t{bar t} candidates. To account for the unconstrained event kinematics, we scan over the phase space of the azimuthal angles ({phi}{sub {nu}1}, {phi}{sub {nu}2}) of neutrinos and reconstruct the top quark mass for each {phi}{sub {nu}1}, {phi}{sub {nu}2} pair by minimizing a {chi}{sup 2} function in the t{bar t} dilepton hypothesis. We assign {chi}{sup 2}-dependent weights to the solutions in order to build a preferred mass for each event. Preferred mass distributions (templates) are built from simulated t{bar t} and background events, and parameterized in order to provide continuous probability density functions. A likelihood fit to the mass distribution in data as a weighted sum of signal and background probability density functions gives a top quark mass of 165.5{sub -3.3}{sup +3.4}(stat.){+-}3.1(syst.) GeV/c{sup 2}.
Date: January 1, 2009
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D. et al.
Object Type: Article
System: The UNT Digital Library
Direct Measurement of the W Production Charge Asymmetry in p anti-p Collisions at s**(1/2) = 1.96-TeV (open access)

Direct Measurement of the W Production Charge Asymmetry in p anti-p Collisions at s**(1/2) = 1.96-TeV

We present the first direct measurement of the W production charge asymmetry as a function of the W boson rapidity y{sub W} in p{bar p} collisions at {radical}s = 1.96 TeV. We use a sample of W {yields} e{nu} events in data from 1 fb{sup -1} of integrated luminosity collected using the CDF II detector. In the region |y{sub W}| < 3.0, this measurement is capable of constraining the ratio of up and down quark momentum distributions in the proton more directly than in previous measurements of the asymmetry that are a function of the charged-lepton pseudorapidity.
Date: January 1, 2009
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type: Article
System: The UNT Digital Library
Search for the Decays B0(s) ---> e+ mu- and B0(s) ---> e+ e- in CDF Run. II. (open access)

Search for the Decays B0(s) ---> e+ mu- and B0(s) ---> e+ e- in CDF Run. II.

The authors report results from a search for the lepton flavor violating decays B{sub (s)}{sup 0} {yields} e{sup +}{mu}{sup -}, and the flavor-changing neutral-current decays B{sub (s)}{sup 0} {yields} e{sup +}e{sup -}. The analysis uses data corresponding to 2 fb{sup -1} of integrated luminosity of p{bar p} collisions at {radical}s = 1.96 TeV collected with the upgraded Collider Detector (CDF II) at the Fermilab Tevatron. The observed number of B{sub (s)}{sup 0} candidates is consistent with background expectations. The resulting bayesian upper limits on the branching ratios at 90% credibility level are {Beta}(B{sub s}{sup 0} {yields} e{sup +}{mu}{sup -}) < 2.0 x 10{sup -7}, {Beta}(B{sup 0} {yields} e{sup +}{mu}{sup -}) < 6.4 x 10{sup -8}, {Beta}(B{sub s}{sup 0} {yields} e{sup +}e{sup -}) < 2.8 x 10{sup -7} and {Beta}(B{sup 0} {yields} e{sup +}e{sup -}) < 8.3 x 10{sup -8}. From the limits on {Beta}(B{sub (s)}{sup 0} {yields} e{sup +}{mu}{sup -}), the following lower bounds on the Pati-Salam leptoquark masses are also derived: M{sub LQ}(B{sub s}{sup 0} {yields} e{sup +}{mu}{sup -}) > 47.8 TeV/c{sup 2}, and M{sub LQ}(B{sup 0} {yields} e{sup +}{mu}{sup -}) > 59.3 TeV/c{sup 2}, at 90% credibility level.
Date: January 1, 2009
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type: Article
System: The UNT Digital Library
Search for production of single top quarks via $tcg$ and $tug$ flavor-changing neutral current couplings (open access)

Search for production of single top quarks via $tcg$ and $tug$ flavor-changing neutral current couplings

None
Date: January 1, 2008
Creator: Abazov, : V.
Object Type: Article
System: The UNT Digital Library
Lifetime difference and CP-violating phase in the B0(s) system (open access)

Lifetime difference and CP-violating phase in the B0(s) system

None
Date: January 1, 2007
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the charge asymmetry in semileptonic Bs decays (open access)

Measurement of the charge asymmetry in semileptonic Bs decays

The authors have performed the first direct measurement of the time integrated flavor untagged charge asymmetry in semileptonic B{sub s}{sup 0} decays, A{sub SL}{sup a,unt}, by comparing the decay rate of B{sub s}{sup 0} {yields} {mu}{sup +} D{sub s}{sup -}{nu}X, where D{sub s}{sup -} {yields} {phi}{pi}{sup -} and {phi} {yields} K{sup +}K{sup -}, with the charge-conjugate {bar B}{sub s}{sup 0} decay rate. This sample was selected from 1.3 fb{sup -1} of data collected by the D0 experiment in Run II of the Fermilab Tevatron collider. They obtain A{sub SL}{sup a,unt} = [1.23 {+-} 0.97(stat) {+-} 0.17(syst)] x 10{sup -2}. Assuming that {Delta}m{sub s}/{bar {Lambda}}{sub s} >> 1 and {Delta}{Lambda}{sub a}/(2{bar {Lambda}}{sub s}) < 1, this result can be translated into a measurement on the CP-violating phase in B{sub s}{sup 0} mixing: {Delta}{Lambda}{sub s}/{Delta}m{sub s} {center_dot} tan {phi}{sub s} = [2.45 {+-} 1.93(stat) {+-} 0.35(syst)] x 10{sup -2}.
Date: January 1, 2007
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the t anti-t production cross section and top quark mass extraction using dilepton events in p anti-p collisions (open access)

Measurement of the t anti-t production cross section and top quark mass extraction using dilepton events in p anti-p collisions

We present a measurement of the top quark pair production cross section in p{bar p} collisions at {radical}s = 1.96 TeV using approximately 1 fb{sup -1} of data collected with the D0 detector. We consider decay channels containing two high p{sub T} charged leptons where one lepton is identified as an electron or a muon while the other lepton can be an electron, a muon or a hadronically decaying {tau} lepton. For a mass of the top quark of 170 GeV, the measured cross section is 7.5{sub -1.0}{sup +1.0}(stat){sub -0.06}{sup +0.7}(syst){sub -0.5}{sup 0.6}(lumi) pb. Using {ell}{sub {tau}} events only, they measure: {sigma}{sub t{bar t}} x B(t{bar t} {yields} {ell}{sub {tau}}b{bar b}) = 0.13{sub -0.08}{sup +0.09}(stat){sub -0.06}{sup 0.06}(syst)+{sub -0.02}{sup +0.02}(lumi) pb. Comparing the measured cross section as a function of the mass of the top quark with a partial next-to-next-to leading order Quantum Chromodynamics theoretical prediction, we extract a mass of the top quark of 171.5{sub -8.8}{sup +9.9} GeV, in agreement with direct measurements.
Date: January 1, 2009
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for admixture of scalar top quarks in the t anti-t lepton+jets final state at s**(1/2) = 1.96-TeV (open access)

Search for admixture of scalar top quarks in the t anti-t lepton+jets final state at s**(1/2) = 1.96-TeV

A search for pair production of the lightest supersymmetric partner of the top quark, {tilde t}{sub 1}, is performed in the lepton+jets channel using 0.9 fb{sup -1} of data collected by the D0 experiment. Kinematic differences between {tilde t}{sub 1}{bar {tilde t}}{sub 1} and the dominant top quark pair production background are used to separate the two processes. First limits from Run II of the Fermilab Tevatron Collider for the scalar top quark decaying to a chargino and a b quark ({tilde t}{sub 1} {yields} {tilde {chi}}{sub 1}{sup +} b) are obtained for scalar top quark masses of 130-190 GeV and chargino masses of 90-150 GeV.
Date: January 1, 2009
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for associated production of charginos and neutralinos in the trilepton final state using 2.3 fb**-1 of data (open access)

Search for associated production of charginos and neutralinos in the trilepton final state using 2.3 fb**-1 of data

We report the results of a search for associated production of charginos and neutralinos using a data set corresponding to an integrated luminosity of 2.3 fb{sup -1} collected with the D0 experiment during Run II of the Tevatron proton-antiproton collider. Final states containing three charged leptons and missing transverse energy are probed for a signal from supersymmetry with four dedicated trilepton event selections. No evidence for a signal is observed, and we set limits on the product of production cross section and leptonic branching fraction. Within minimal supergravity, these limits translate into bounds on m{sub 0} and m{sub 1/2} that are well beyond existing limits.
Date: January 1, 2009
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for excited electrons in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for excited electrons in p anti-p collisions at s**(1/2) = 1.96-TeV

We present the results of a search for the production of an excited state of the electron, e*, in proton-antiproton collisions at {radical}s = 1.96 TeV. The data were collected with the D0 experiment at the Fermilab Tevatron Collider and correspond to an integrated luminosity of approximately 1 fb{sup -1}. We search for e* in the process p{bar p} {yields} e*e, with the e* subsequently decaying to an electron plus photon. No excess above the standard model background is observed. Interpreting our data in the context of a model that describes e* production by four-fermion contact interactions and e* decay via electroweak processes, we set 95% C.L. upper limits on the production cross section ranging from 8:9 fb to 27 fb, depending on the mass of the excited electron. Choosing the scale for contact interactions to be {Lambda} = 1 TeV, excited electron masses below 756 GeV are excluded at the 95% C.L.
Date: January 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for pair production of second generation scalar leptoquarks in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for pair production of second generation scalar leptoquarks in p anti-p collisions at s**(1/2) = 1.96-TeV

The authors report on a search for the pair production of second generation scalar leptoquarks (LQ{sub 2}) in p{bar p} collisions at the center-of-mass energy {radical}s = 1.96 TeV, using data corresponding to an integrated luminosity of 294 {+-} 19 pb{sup -1} recorded with the D0 detector. No evidence for a leptoquark signal in the LQ{sub 2} {ovr LQ}{sub 2} {yields} {mu}q{mu}q channel has been observed, and upper bounds on the product of cross section times branching fraction were set. This yields lower mass limits of m{sub LQ{sub 2}} > 247 GeV for {beta} = {Beta}(LQ{sub 2} {yields} {mu}q) = 1 and m{sub LQ{sub 2}} > 182 GeV for {beta} = 1/2. Combining these limits with previous D0 results, the lower limits on the mass of a second generation scalar leptoquark are m{sub LQ{sub 2}} > 251 GeV and m{sub LQ{sub 2}} > 204 GeV for {beta} = 1 and {beta} = 1/2, respectively.
Date: January 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library