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In vivo collection of rare proteins using kinesin-based "nano-harvesters".

Description: In this project, we have developed a novel platform for capturing, transport, and separating target analytes using the work harnessed from biomolecular transport systems. Nanoharvesters were constructed by co-organizing kinesin motor proteins and antibodies on a nanocrystal quantum dot (nQD) scaffold. Attachment of kinesin and antibodies to the nQD was achieved through biotin-streptavidin non-covalent bonds. Assembly of the nanoharvesters was characterized using a modified enzyme-linked immunosorbent assay (ELISA) that confirmed attachment of both proteins. Nanoharvesters selective against tumor necrosis factor-{alpha} (TNF-{alpha}) and nuclear transcription factor-{kappa}B (NF-{kappa}B) were capable of detecting target antigens at <100 ng/mL in ELISAs. A motility-based assay was subsequently developed using an antibody-sandwich approach in which the target antigen (TNF-{alpha}) formed a sandwich with the red-emitting nanoharvester and green-emitting detection nQD. In this format, successful sandwich formation resulted in a yellow emission associated with surface-bound microtubules. Step-wise analysis of sandwich formation suggested that the motility function of the kinesin motors was not adversely affected by either antigen capture or the subsequent binding of the detection nQDs. TNF-{alpha} was detected as low as {approx}1.5 ng/mL TNF-{alpha}, with 5.2% of the nanoharvesters successfully capturing the target analyte and detection nQDs. Overall, these results demonstrate the ability to capture target protein analytes in vitro using the kinesin-based nanoharvesters in nanofluidic environments. This system has direct relevance for lab-on-a-chip applications where pressure-driven or electrokinetic movement of fluids is impractical, and offers potential application for in vivo capture of rare proteins within the cytoplasmic domain of live cells.
Date: November 1, 2008
Creator: Bachand, Marlene; Bachand, George David; Greene, Adrienne Celeste & Carroll-Portillo, Amanda
Partner: UNT Libraries Government Documents Department

RF/Microwave properties and applications of directly assembled nanotubes and nanowires: LDRD project 102662 final report.

Description: LDRD Project 102662 provided support to pursue experiments aimed at measuring the basic electrodynamic response and possible applications of carbon nanotubes and silicon nanowires at radiofrequency to microwave frequencies, approximately 0.01 to 50 GHz. Under this project, a method was developed to integrate these nanomaterials onto high-frequency compatible co-planar waveguides. The complex reflection and transmission coefficients of the nanomaterials was studied as a function of frequency. From these data, the high-frequency loss characteristics of the nanomaterials were deduced. These data are useful to predict frequency dependence and power dissipation characteristics in new rf/microwave devices incorporating new nanomaterials.
Date: November 1, 2006
Creator: Mayer, Theresa (The Pennyslvania State University, University Park, PA 16802); Vallett, Aaron (The Pennyslvania State University, University Park, PA 16802); Lee, Mark; Shaner, Eric Arthur; Jones, Frank E.; Talin, Albert Alec et al.
Partner: UNT Libraries Government Documents Department

Microwave to millimeter-wave electrodynamic response and applications of semiconductor nanostructures: LDRD project 67025 final report.

Description: Solid-state lighting (SSL) technologies, based on semiconductor light emitting devices, have the potential to reduce worldwide electricity consumption by more than 10%, which could significantly reduce U.S. dependence on imported energy and improve energy security. The III-nitride (AlGaInN) materials system forms the foundation for white SSL and could cover a wide spectral range from the deep UV to the infrared. For this LDRD program, we have investigated the synthesis of single-crystalline III-nitride nanowires and heterostructure nanowires, which may possess unique optoelectronic properties. These novel structures could ultimately lead to the development of novel and highly efficient SSL nanodevice applications. GaN and III-nitride core-shell heterostructure nanowires were successfully synthesized by metal organic chemical vapor deposition (MOCVD) on two-inch wafer substrates. The effect of process conditions on nanowire growth was investigated, and characterization of the structural, optical, and electrical properties of the nanowires was also performed.
Date: November 1, 2006
Creator: Shaner, Eric Arthur; Lee, Mark; Averitt, R. D. (Los Alamos National Laboratory); Highstrete, Clark; Taylor, A. J. (Los Alamos National Laboratory); Padilla, W. J. (Los Alamos National Laboratory) et al.
Partner: UNT Libraries Government Documents Department

Quantification of false positive reduction in nucleic acid purification on hemorrhagic fever DNA.

Description: Columbia University has developed a sensitive highly multiplexed system for genetic identification of nucleic acid targets. The primary obstacle to implementing this technology is the high rate of false positives due to high levels of unbound reporters that remain within the system after hybridization. The ability to distinguish between free reporters and reporters bound to targets limits the use of this technology. We previously demonstrated a new electrokinetic method for binary separation of kb pair long DNA molecules and oligonucleotides. The purpose of this project 99864 is to take these previous demonstrations and further develop the technique and hardware for field use. Specifically, our objective was to implement separation in a heterogeneous sample (containing target DNA and background oligo), to perform the separation in a flow-based device, and to develop all of the components necessary for field testing a breadboard prototype system.
Date: November 1, 2006
Creator: James, Conrad D.; Pohl, Kenneth Roy; Derzon, Mark Steven; McClain, Jaime & Achyuthan, Komandoor
Partner: UNT Libraries Government Documents Department

The screening of the lamb shift in heavy helium-like ions. Final technical report

Description: The project was undertaken in collaboration with Dr. Neal Snyderman of Lawrence Livermore National Laboratory (LLNL) through a project under the directorship of Dr. Kennedy Reed of LLNL. It is a collaboration of the work started at LLNL during the summers of 1994 and 1995, and continued at Spelman College. Spelman students Adrienne Stiff and Joy Harris were supported under this project. The main question under investigation was whether a Sturmian representation of the electron Green function is suitable for numerical calculations of QED effects in high-Z helium-like atoms. The frequency-independent part of the two-photon exchange graphs was calculated with this representation and compared with the results of other recent calculations. Only the Coulomb part of these graphs were calculated under this project.
Date: November 1, 1997
Creator: Hylton, D.J.
Partner: UNT Libraries Government Documents Department

In situ soil remediation using electrokinetics

Description: Electrokinetics is emerging as a promising technology for in situ soil remediation. This technique is especially attractive for Superfund sites and government operations which contain large volumes of contaminated soil. The approach uses an applied electric field to induce transport of both radioactive and hazardous waste ions in soil. The transport mechanisms include electroosmosis, electromigration, and electrophoresis. The feasibility of using electrokinetics to move radioactive {sup 137}Cs and {sup 60}Co at the Hanford Site in Richland, Washington, is discussed. A closed cell is used to provide in situ measurements of {sup 137}Cs and {sup 60}Co movement in Hanford soil. Preliminary results of ionic movement, along with the corresponding current response, are presented.
Date: November 1, 1994
Creator: Buehler, M. F.; Surma, J. E. & Virden, J. W.
Partner: UNT Libraries Government Documents Department

Atomic Physics Aspects of a Relativistic Nuclear Collider

Description: Atomic collision cross sections involving bare uranium nuclei are large at relativistic energies and will affect the design and operation of a relativistic nuclear collider (RNC). The most significant may be production of electron-positron pairs and muon pairs ({approx} 10{sup 8} per sec. and 2000 per sec. respectively for a 100 GeV/nucleon collider with a luminosity of 10{sup 27} cm{sup 2} s{sup -1}). Although the pair production is a direct measure of the luminosity it is also a large source of background and capture of an electron from the pair by one of the nuclei will result in the loss of the ion. Another important loss mechanism is Coulomb excitation of the giant nuclear dipole and giant nuclear quadrupole resonances. Storing and colliding bare and highly-stripped uranium opens up new possibilities for novel atomic physics experiments and an alternate approach for present experiments. As examples, the use of a collider for experiments to study spontaneous decay of the super-critical state (both positron production and x-ray production) of quasi-atoms of atomic number Z > 172, and a storage-ring measurement of the ground state hyperfine structure of hydrogen like thallium as a test of quantum electrodynamics (QED) are discussed.
Date: November 1, 1984
Creator: Gould, R.
Partner: UNT Libraries Government Documents Department

Key contributions in MHD power generation. Quarterly report, 1 June 1979-31 August 1979

Description: Activities during the third quarter of the contract period are reported in detail. The tasks reported on include: (1) investigation of electrical behavior in the vicinity of electrode and insulating walls; (2) studies of critical performance issues in the development of combustion disk generators; (3) development and testing of electrode modules, including studies of insulator properties; and (4) determination of coal combustion kinetics and ash behavior relevant to two-stage MHD combustors, and investigation of the mixing and flow aerodynamics of a high swirl geometry second stage.
Date: November 1, 1979
Creator: Louis, J F
Partner: UNT Libraries Government Documents Department

Results from the crystal ball detector at SPEAR

Description: The Crystal Ball detector is a device particularly suited to the measurement of photons with energies lower than 1 GeV. The detector has as its principal component a 16 radiation length thick, highly segmented shell of NaI(Tl) surrounding cylindrical, proportional, and magnetostrictive spark chambers. The main Ball and various elements of the central chambers cover 94% of 4..pi.. sr. Segmented endcap NaI(Tl) detectors of 20 radiation lengths behind magneto strictive spark chambers supplement the main Ball. The Ball and endcaps close the solid angle for charged particle and photon detection to 98% of 4..pi.. sr. In addition, detectors of interspersed iron and proportional tubes provide for ..mu..-..pi.. separation over 15% of 4..pi.. sr, about theta/sub CM/ = 90/sup 0/. In this report preliminary results are presented from the data obtained. In particular, QED at E/sub CM/ = 6.5 GeV, R/sub hadron/ and related inclusive distributions, eta branching fractions at J/psi and psi'', and a detailed study of the psionium system are discussed.
Date: November 1, 1979
Creator: Bloom, E.D.
Partner: UNT Libraries Government Documents Department

Strong coupling QED with two fermionic flavors

Description: We report the recent results of our simulation of strong coupling QED, with non-compact action, on lattices 10{sup 4} and 16{sup 4}. Since we are dealing with two staggered fermionic flavors, we use hybrid algorithm to do the simulation. In addition to the measurement of the chiral order parameter {l angle}{bar {psi}}{psi}{r angle}, we also measure magnetic monopole susceptibility, {chi}, throughout the region of chiral transition. 6 refs., 6 figs.
Date: November 1, 1990
Creator: Wang, K.C.
Partner: UNT Libraries Government Documents Department

Preliminary results from ASP on tests of QED to order. cap alpha. /sup 4/ in e/sup +/e/sup -/ annihilation at. sqrt. s = 29 GeV

Description: Tests of QED to order ..cap alpha../sup 4/ performed with the ASP detector at PEP are presented. Measurements have been made of exclusive e/sup +/e/sup -/e/sup +/e/sup -/, e/sup +/e/sup -/..gamma gamma.. and ..gamma gamma gamma gamma.. final states with all particles above 50 milliradians with respect to the e/sup +/e/sup -/ beam line. These measurements represent a significant increase in statistics over previous measurements. All measurements agree well with theoretical predictions. 5 refs., 1 tab.
Date: November 1, 1988
Creator: Hawkins, C.A.
Partner: UNT Libraries Government Documents Department

Hard photon processes in electron-positron annihilation at 29 GeV

Description: The hard photon processes ..mu mu gamma.. and hadrons + ..gamma.. in e/sup +/e/sup -/ annihilation at 29 GeV have been studied. The study is based on an integrated luminosity of 226 pb/sup -1/ taken at PEP with the Mark II detector. For the ..mu mu gamma.. process, a small fraction of non-planar events are observed with missing momentum along the beam direction. The resulting missing energy spectrum is consistent with that expected from higher order effects. The observed cross section is consistent with the predicted cross section for this process, sigma/sup exp/sigma/sup th/ = .90 +- .05 +- .06. The observed hard photon energy spectrum and mass distributions are found to be in agreement with O(..cap alpha../sup 3/) QED. The measured charge asymmetry is in good agreement with the predicted value, A/sub exp/A/sub th/ = .83 +- .25 +- .12. The ..mu gamma.. invariant mass distribution is used to place a limit on a possible excited muon coupling G..gamma../M* for excited muon masses in the range 1 < M* < 21 GeV of (G..gamma../M*)/sup 2/ < 10/sup -5/ GeV/sup -2/ at a 95% confidence level. In the hadrons + ..gamma.. process, evidence for final state radiation is found in an excess of events over that predicted from initial state radiation alone of 253 +- 54 +- 60 events. Further evidence for final state radiation is found in a large hadronic charge asymmetry A/sub Had+..gamma../= (-24.6 +- 5.5)%.
Date: November 1986
Creator: Gold, M. S.
Partner: UNT Libraries Government Documents Department