[en] Several topics in field theory are investigated. (1) Massive higher spin actions are obtained as gauge theories from the dimensional reduction of the corresponding massless ones. (2) The author considers a model of spin4 and spin2 interaction through the Bel-Robinson tensor of spin2 field, which in conserved at free level. The coupling is inconsistent, yet there are indications that adding still higher spin couplings would be a promising direction to achieve consistency. (3) Energy and Stability of Einstein-Gauss-Bonnet models of gravity are studied. It is shown that flat space is stable while AdS is not. (4) Gauged Wess-Zumino-Witten models are studied in detail. The equivalence to GKO construction of conformal field theory is considered. BRST quantization of the models is given. (5) Nonrenormalizability of quantum gravity is, in the binomial first order metric formulation, traced to a mismatch between the symmetries of its quadratic and cubic term. (6) The possibility that the gravitational model defined in D = 3 by an action which is the sum of Einstein and Chern-Simons terms is a viable quantum theory is investigated. It is shown that it is compatible with power-counting renormalizability. Gauge invariant regularizations, however, have not been found to exist. Detailed BRS analysis shows that there are possible anomalies

[en] This dissertation consists of two parts. The last part is eight research papers which involve topics related to High T_c superconductor (HTSC) studies. The main topic describes the interaction between a permanent magnet and a HTSC studied by a mechanical pendulum. The first part of the dissertation has two purposes. One is to give a brief introduction and background to the research papers, and the other is to outline the scientific findings from the HTSC studies. 94 refs., 2 figs

[en] 45% Ni-55% Fe films were deposited onto (1 0 0) Si substrate via radio frequency (RF) magnetron sputtering. The influence of composition, RF input power, argon pressure, substrate-to-target distance on the magnetic and structural properties of the films was investigated. X-ray diffraction (XRD) measurements indicate that the films had the fcc structure and exhibited a dominant (1 1 1) orientation. The maximum saturation magnetization (4πM_s∼16 kG) could be obtained for films with the composition Fe_54.5Ni_45.5. Depending on deposition conditions, the film coercivity could be varied from 10 to 60 Oe. After annealing at 400 deg. C for 1 h, the particles grew bigger, the films orientation did not change obviously, still showed (1 1 1) orientation, and the coercivity decreased. After annealing, the optimal magnetic properties can be obtained in the films as follows: the saturation magnetization 4πM_s∼16 kG, the easy axis of less than 2 Oe, and the hard axis coercivity of less than 1 Oe

[en] The concrete-filed square steel tube with inner I-shaped CFRP profiles short columns under bi-axial eccentric load were investigated by the finite element analysis software ABAQUS. The working mechanism of the composite columns which is under bi-axial eccentric load are investigated by using the stress distribution diagram of steel tube concrete and the I-shaped CFRP profiles. In this paper, the main parameters; eccentric ratio, steel ratio, steel yield strength, concrete compressive strength and CFRP distribution rate of the specimens were investigated to know the mechanical behavior of them. The interaction between the steel tube and the concrete interface at different characteristic points of the composite columns were analyzed. The results showed that the ultimate bearing capacity of the concrete-filed square steel tube with inner I-shaped CFRP profiles short columns under bi-axial eccentric load decrease with the increase of eccentric ratio, the ultimate bearing capacity of the composite columns increase with the increase of steel ratio, steel yield strength, concrete compressive strength and CFRP distribution rate. The contact pressure between the steel tube and the concrete decreased from the corner zone to the flat zone, and the contact pressure decreased from the mid-height cross section to other sections. (Author)

[en] We have performed an analysis of the diffuse gamma-ray emission with the Fermi Large Area Telescope in the Milky Way Halo region searching for a signal from dark matter annihilation or decay. We consider both gamma rays produced directly in the dark matter annihilation/decay and produced by inverse Compton scattering of the e⁺/e⁻ produced in the annihilation/decay. Conservative limits are derived requiring that the dark matter signal does not exceed the observed diffuse gamma-ray emission. A second set of more stringent limits is derived based on modeling the foreground astrophysical diffuse emission. Uncertainties in the height of the diffusive cosmic-ray halo, the distribution of the cosmic-ray sources in the Galaxy, the cosmic-ray electron index of the injection spectrum and the column density of the interstellar gas are taken into account using a profile likelihood formalism, while the parameters governing the cosmic-ray propagation have been derived from fits to local cosmic-ray data. The resulting limits impact the range of particle masses over which dark matter thermal production in the early Universe is possible, and challenge the interpretation of the PAMELA/Fermi-LAT cosmic ray anomalies as annihilation of dark matter

[en] Motivated by recent progress on non-perturbative 2D quantum gravity, we reconsider the superLiouville action for N=2 2D supergravity and its properties carefully, thus refining some of the previous treatments. Based on the new results we speculate upon whether it is a sensible theory for any D. (orig.)

[en] We discuss adding 'quarks' to random matrix models. We then study the Veneziano type random matrix model in D=1. It is found that there is no spontaneous tearing of the world sheet. If we instead take dynamical loops according to Kazakov in D=1, a phase structure similar to that of D=0 occurs. The loops are necessarily generated by bosonic 'quarks'. (orig.)

[en] We have synthesized N-[3-(2',4'-dichlorophenoxy)-2-¹⁸F-fluoropropyl]-N-methylpropargylamine (¹⁸F-fluoroclorgyline) as a potential positron emission tomography (PET) radiotracer for monoamine oxidase A (MAO-A). The radiosynthesis was carried out by a ¹⁸F-fluoride-for-mesylate substitution reaction in approximately 20% radiochemical yield in specific activities of 1-2 Ci/μmol. Selectivity for MAO-A was demonstrated by the high affinity of clorgyline ( IC₅₀=39 nM) and lower affinity of (R)-deprenyl ( IC₅₀≥100 μM) for the inhibition of ¹⁸F-fluoroclorgyline binding in vitro in rat brain membranes. The uptake of ¹⁸F-fluoroclorgyline in the rat brains was high (>1.0% injected dose/g). The binding of ¹⁸F-fluoroclorgyline in the rat brain correlated with the distribution of MAO-A and was inhibited by preadministration of MAO-A inhibitors, clorgyline, and Ro 41-1049, whereas (R)-deprenyl, a MAO-B blocker, had no inhibitory effect. These results suggest that ¹⁸F-fluoroclorgyline is a potential PET radiotracer for MAO-A

[en] Temporal relaxation of rubbed polystyrene (PS) thin films (50 nm thick) was studied by probing the decay of the optical anisotropy in the sample. Our results show that the relaxation process is characterized by two single-exponential decays plus a temperature-dependent constant. Both relaxations are orders of magnitude faster than the main chain (α) relaxation at temperatures well below (>10 degreeC)T_g, with activation energies 3.0 kcal/mol and 5.1 kcal/mol, respectively, either of which are much smaller than that of the α relaxation (∼50 kcal/mol). The decay time constants are found to be independent of the sample molecular weights M_w (=13.7 K to 550 K Daltons, M_w/M_n≤1.1) at these temperatures. This shows the local nature of the relaxation modes of rubbed PS

[en] We compute n-point functions in D=1 random surfaces from an effective field theory. The results are useful to show certain universality in the low momentum p regime. (orig.)