[en] Ba₅LnZnTa₉O₃₀ (Ln=La, Sm) ceramics were prepared by high temperature solid-state reaction route. The samples were characterized by X-ray diffraction, scanning electron microscopy (SEM), and differential scanning calorimetry (DSC) methods. They belong to paraelectric phase of filled tetragonal TB structure at room temperature with unit cell a=12.5909(4) A, c=3.9622(2) A for Ba₅LaZnTa₉O₃₀; and a=12.5777(4) A, c=3.9544(2) A for Ba₅SmZnTa₉O₃₀. At 1 MHz, Ba₅LaZnTa₉O₃₀ has high dielectric constants of 89 with low dielectric loss 0.0067, and temperature coefficients of the dielectric constant (τ_ε) -811 ppm deg. C^-1; Ba₅LaZnTa₉O₃₀ has dielectric constants of 74 with low dielectric loss 0.0035, and τ_ε -474 ppm deg. C^-1

[en] Theoretical estimates of the length scale and amplitude of the dominant component of large scale inhomogeneities (less than a few hundred Mpc) in the universe are discussed. A table is given which lists the known length scales and amplitudes of visible objects in the universe, based on theoretical calculations and observations, and a nearest-neighbor test for quasar distribution is derived from observations by Savage and Bolton (1979). Evidence is given for the existence of invisible matter in the universe, and an upper limit is calculated for inhomogeneities in a universe dominated by invisible matter. The upper limit of the homogeneities is given as the gravitational scintillation of the microwave background. It is shown that the inhomogeneity for total matter distribution is much smaller than that for visible nucleon matter as long as the universe is dominated by invisible matter

[en] Consideration is given to some theoretical issues in the problem of matter clustering in a neutrino-dominated universe. Among the topics discussed are: the role of right-handedness and left-handedness in neutrino interactions; Jeans instability; and Jeans coupling in a two-component field of massive neutrinos. On the basis of the theoretical discussion, a quantitative analysis is presented of the collapsing stage of clustering in an overdense region with a spherically symmetrical configuration

[en] The various methods of determining the deceleration parameter q(0) are reviewed. The Hubble diagram method for galaxies and various subsets of quasars consistently gives q(0) greater than 1/2, the mean mass density method always gives q(0) less than 1/2, while the theta-z method more often than not follows the Euclidean relation where theta varies as the inverse of z. Thus, the ultimate question of whether the universe is open or closed now hinges on the question as to which factor is more important: luminosity decrease or the existence of a quasi-uniform nonluminous nonbaryonic mass distribution. The present authors are inclined to the second alternative because it makes use of, rather than ignores, the clue from the mean density results. The recent discovery of a non-zero rest-mass of the electron neutrino offers a possible identification of the postulated mass distribution

[en] Separate theoretical classifications are proposed for two classes of objects with core-halo structure, loaded polytropes and loaded neutrino objects. The classifications are based on a solution to the relativistic Emden equation which describes the different density distributions and stable equilibrium configurations of both the loaded polytropes and the loaded neutrino objects. The major differences between classical characterizations of compact core objects and the relativistic solution are discussed, and some applications of the theory to the calculation of the redshift distributions of quasars in the Hewitt and Burbridge (1980) catalog are presented

[en] Very thin Tl₂Ba₂CaCu₂O_x (Tl-2212) superconducting films with thickness < 100 nm have been fabricated on LaAlO₃ (0 0 1) substrates using dc magnetron sputtering and post-annealing process in pure argon. For a 100 nm thick film, T_c and J_c (77 K, 0 T) show the values of 105.3 K and 2.33 x 10⁶ A/cm², respectively. A 30 nm thick film with T_c>100 K shows smooth surface morphology and high quality epitaxy. A 20 nm thick film revealed full transition to superconductivity at temperature of 98.7 K. The superconductivity and surface morphology of the very thin film deteriorated rapidly as the film thickness below 20 nm. A 6 nm thick Tl-2212 film was not found to be superconducting at temperature down to 15 K. In our experiments the critical film thickness leading to degradation of the superconducting properties was 20 nm

[en] The influence of massive neutrinos upon the clustering process of cosmological matter in the early Jeans instability stage has been studied in the standard big bang cosmology

[en] The possibility of thermally induced initial density perturbations in inflationary cosmology is examined. The fluctuation dynamics of a scalar field plus a thermal bath system during slow roll is described by a Langevin-like equation. Fluctuation-dissipation arguments show that for a wide parameter range within the standard inflation model, the thermal fluctuations of the scalar field can dominate its quantum fluctuations. The initial amplitude of density perturbations is found to lie in a range which is consistent with the recent observations of cosmic temperature fluctuations

[en] A beam line U2A for microscopy, SEXAFS, and soft X-ray holography is being designed at NSRL, USTC, China. A preliminary design for U2A is presented, utilizing a linear monochromator consisting of a zone plate and a diaphragm. The parameters for these elements are as follows: the condenser zone plate has D = 6.0 mm, N = 10000, deltaRn = 0.15 μm, and F = 204.5 mm. The diaphragm has d = 24 μm. A spectral resolution lambda/Δlambda = 125 would be achieved. (orig.)

[en] Recent epidemiological studies have found that women infected with both herpes simplex virus type 2 (HSV-2) and human papillomavirus (HPV) type 16 or HPV-18 are at greater risk of developing cervical carcinoma compared to women infected with only one virus. However, it remains unclear if HSV-2 is a cofactor for cervical cancer or if HPV and HSV-2 interact in any way. We have studied the effect of HSV-2 infection on HPV-11 gene expression in an in vitro double-infection assay. HPV transcripts were down-regulated in response to HSV-2 infection. Two HSV-2 vhs mutants failed to reduce HPV-16 E1-circumflexE4 transcripts. We also studied the effect of HSV-2 infection on preexisting experimental papillomas in a vaginal epithelial xenograft model. Doubly infected grafts demonstrated papillomatous transformation and the classical cytopathic effect from HSV-2 infection. HPV and HSV DNA signals were mutually exclusive. These studies may have therapeutic applications for HPV infections and related neoplasms