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Final report: Photochromism as a switching mechanism for electronically active organic materials
Recent discoveries in the field of conjugated polymers in environmental stability, regiochemical regularity, and electrical conductivity, particularly of polythiophene and polyaniline, have intensified interest in device applications. Present or anticipated applications include development of electrical circuitry on a molecular scale, as well as conducting and semiconducting materials for a variety of applications including thin film transistors and batteries. The authors have investigated a series of compounds comprising conjugated segments coupled to photochromic elements. The photochromic reaction in these compounds reversibly alters the conjugation length and provides a mechanism for switching both the electrical and optical properties of these materials. The authors are currently investigating the nature and scope of this switching mechanism and preparing extended materials that take advantage of this novel form of switching behavior. Preparation and photochromic behavior of several of these materials are described
Positive Pion Production from the Bombardment of 11-B, 12-C, and 40-Ca by 146-159 MeV Polarized Protons
Supported by the National Science Foundation and Indiana Universit
Measurement of Charged Pion Yields from Nuclei in (p,Pi+) Reactions Very Near Threshold
This work was supported by National Science Foundation Grants PHY 76-84033A01, PHY 78-22774, and Indiana Universit
Competition between local and nonlocal dissipation effects in two-dimensional quantum Josephson junction arrays
We discuss the local and nonlocal dissipation effects on the existence of the
global phase coherence transitions in two dimensional Josephson-coupled
junctions. The quantum phase transitions are also examined for various lattice
geometries: square, triangular and honeycomb. The T=0 superconductor-insulator
phase transition is analyzed as a function of several control parameters which
include self-capacitance and junction capacitance and both local and nonlocal
dissipation effects. We found the critical value of the nonlocal dissipation
parameter \alpha_{1} depends on a geometry of the lattice. The critical value
of the normal state conductance seems to be difficult to obtain experimentally
if we take into consideration different damping mechanisms which are presented
in real physical systems.Comment: accepted to Physica C Ref. No.: PHYSC-D-06-00244R
Catch-up growth in the first two years of life in Extremely Low Birth Weight (ELBW) infants is associated with lower body fat in young adolescence
Aim To investigate growth patterns and anthropometrics in former extremely low birth weight (ELBW, <1000 g) children and link these outcomes to neurocognition and body
Continuous Quantum Measurement and the Quantum to Classical Transition
While ultimately they are described by quantum mechanics, macroscopic
mechanical systems are nevertheless observed to follow the trajectories
predicted by classical mechanics. Hence, in the regime defining macroscopic
physics, the trajectories of the correct classical motion must emerge from
quantum mechanics, a process referred to as the quantum to classical
transition. Extending previous work [Bhattacharya, Habib, and Jacobs, Phys.
Rev. Lett. {\bf 85}, 4852 (2000)], here we elucidate this transition in some
detail, showing that once the measurement processes which affect all
macroscopic systems are taken into account, quantum mechanics indeed predicts
the emergence of classical motion. We derive inequalities that describe the
parameter regime in which classical motion is obtained, and provide numerical
examples. We also demonstrate two further important properties of the classical
limit. First, that multiple observers all agree on the motion of an object, and
second, that classical statistical inference may be used to correctly track the
classical motion.Comment: 12 pages, 4 figures, Revtex
Quantum measurement with chaotic apparatus
We study a dissipative quantum mechanical model of the projective measurement
of a qubit. We demonstrate how a correspondence limit, damped quantum
oscillator can realise chaotic-like or periodic trajectories that emerge in
sympathy with the projection of the qubit state, providing a model of the
measurement process.Comment: 8 pages, 10 figure
Lentiviral Hematopoietic Stem Cell Gene Therapy Corrects Murine Pompe Disease
Pompe disease is an autosomal recessive lysosomal storage disorder characterized by progressive muscle weakness. The disease is caused by mutations in the acid α-glucosidase (GAA) gene. Despite the currently available enzyme replacement therapy (ERT), roughly half of the infants with Pompe disease die before the age of 3 years. Limitations of ERT are immune responses to the recombinant enzyme, incomplete correction of the disease phenotype, lifelong administration, and inability of the enzyme to cross the blood-brain barrier. We previously reported normalization of glycogen in heart tissue and partial correction of the skeletal muscle phenotype by ex vivo hematopoietic stem cell gene therapy. In the present study, using a codon-optimized GAA (GAAco), the enzyme levels resulted in close to normalization of glycogen in heart, muscles, and brain, and in complete normalization of motor function. A large proportion of microglia in the brain was shown to be GAA positive. All astrocytes contained the enzyme, which is in line with mannose-6-phosphate receptor expression and the key role in glycogen storage and glucose metabolism. The lentiviral vector insertion site analysis confirmed no preference for integration near proto-oncogenes. This correction of murine Pompe disease warrants further development toward a cure of the human condition.This publication reports that stem cell gene therapy using a codon-optimized gene encoding acid α-glucosidase (GAA) cures the mouse model of Pompe disease, a lysosomal storage disorder
Status of an Investigation of the 3-He Wave Function by Quasi-Free Scattering
This research was sponsored by the National Science Fooundation Grant NSF PHY-931478
Longitudinal double-spin asymmetry and cross section for inclusive neutral pion production at midrapidity in polarized proton collisions at sqrt(s) = 200 GeV
We report a measurement of the longitudinal double-spin asymmetry A_LL and
the differential cross section for inclusive Pi0 production at midrapidity in
polarized proton collisions at sqrt(s) = 200 GeV. The cross section was
measured over a transverse momentum range of 1 < p_T < 17 GeV/c and found to be
in good agreement with a next-to-leading order perturbative QCD calculation.
The longitudinal double-spin asymmetry was measured in the range of 3.7 < p_T <
11 GeV/c and excludes a maximal positive gluon polarization in the proton. The
mean transverse momentum fraction of Pi0's in their parent jets was found to be
around 0.7 for electromagnetically triggered events.Comment: 6 pages, 3 figures, submitted to Phys. Rev. D (RC
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