Characterization of Dominant Hydrogen Bonded Complex Structures of Dielectric Polarization and Viscous Flow Processes in Glycerol–Formamide Binary Mixtures

The static permittivity and viscosity of glycerol–formamide (Gly–FA) binary mixtures were measured at eleven concentrations over the entire composition range and at temperatures T=288.15, 303.15, 318.15 and 333.15 K. The excess static permittivity and excess viscosity of the mixtures were determined using the mole-fraction additive mixture law. Results indicated that the molecular dielectric polarization in Gly–FA mixtures is governed by 1:1 complexes with a decrease in number of H-bonded parallel aligned dipolar ordering at all of the investigated temperatures. The 2Gly:FA complexes facilitate the viscous flow process and the number of these complexes decreases with increasing temperature. The apparent activation energy of viscous flow, determined from Arrhenius plots, increases with increases of the Gly concentration in the mixtures. The electric-field-induced increment of the Helmholtz free energy and the entropy of these binary mixtures were determined from the temperature dependence of the static permittivity and its derivative, respectively.     

Comprehensive comparison of various techniques for the analysis of elemental distributions in thin films

The present work shows results on elemental distribution analyses in Cu(In,Ga)Se2 thin films for solar cells performed by use of wavelength-dispersive and energy-dispersive X-ray spectrometry (EDX) in a scanning electron microscope, EDX in a transmission electron microscope, X-ray photoelectron, angle-dependent soft X-ray emission, secondary ion-mass (SIMS), time-of-flight SIMS, sputtered neutral mass, glow-discharge optical emission and glow-discharge mass, Auger electron, and Rutherford backscattering spectrometry, by use of scanning Auger electron microscopy, Raman depth profiling, and Raman mapping, as well as by use of elastic recoil detection analysis, grazing-incidence X-ray and electron backscatter diffraction, and grazing-incidence X-ray fluorescence analysis. The Cu(In,Ga)Se2 thin films used for the present comparison were produced during the same identical deposition run and exhibit thicknesses of about 2 μm. The analysis techniques were compared with respect to their spatial and depth resolutions, measuring speeds, availabilities, and detection limits.     

Prediction of low-sensitivity reactive dye recipe in exhaust dyeing influenced by material to liquor ratio and nature of salt

Reactive dyeings were carried out by exhaust method on 100% cotton knits. A trichromatic combination was chosen with only change in blue component. Colorimetric data were produced under controlled dyeing conditions by comparing the color difference between the target shade and resulting shades. Giving a change in liquor ratio and nature of salt the colorimetric data were regenerated again produced the shades. The data will be helpful to predict the low-sensitivity reactive dye recipe, which lead to the concept of right-first-time dyeing. The aim of this research is to help a dyer to select the right recipe. A set of the dye recipes was applied by dyeing with reactive dyes on cotton. Sodium chloride shows best results in terms of dye sensitivity as compared to Glauber's salt at low liquor ratio that is 1:10. Blue BRF in combination with yellow and red shows best result as compared to navy blue BF.     

Silicon slow-light-based photonic mixer for microwave-frequency conversion applications

We describe and demonstrate experimentally a method for photonic mixing of microwave signals by using a silicon electro-optical Mach-Zehnder modulator enhanced via slow-light propagation. Slow light with a group index of ~11, achieved in a one-dimensional periodic structure, is exploited to improve the upconversion performance of an input frequency signal from 1 to 10.25 GHz. A minimum transmission point is used to successfully demonstrate the upconversion with very low conversion losses of ~7 dB and excellent quality of the received I/Q modulated QPSK signal with an optimum EVM of ~8%.     

A Stability-Indicating Assay of Brimonidine Tartrate Ophthalmic Solution and Stress Testing Using HILIC

A stability-indicating hydrophilic interaction liquid chromatography (HILIC) method has been developed and validated for the quantitative determination of Brimonidine tartrate (BT) formulated as an ophthalmic solution. Isocratic separation was achieved using an acetonitrile-buffer mixture (92:8, v/v) at pH 7.1 on an unmodified silica column (250 × 4.6 mm, 5 μm). The drug was subjected to oxidative, hydrolytic, photolytic and thermal stress conditions and complete separation was achieved for the parent compound and degradation products. The influence of acetonitrile, pH and ionic strength of the buffer was studied. Linearity range and recoveries for BT were 100–400 μg mL^?1 and 100.12%, respectively. The method was validated for BT and indicated that the method was sufficiently sensitive with a limit of detection at 0.005 μg mL^?1 and a limit of quantitation at 0.02 μg mL^?1, respectively.     

Extreme ultraviolet and soft x-ray spectral lines in Rb XXIX

An extensive theoretical set of atomic data for Rb XXIX in a wide range with L-shell electron excitations to the M-shell has been reported. We have computed energy levels for the lowest 113 fine structure levels of Rb XXIX. The fully relativistic multiconfigurational Dirac-Fock method (MCDF) within the framework of Dirac-Coulomb Hamiltonian taking quantum electrodynamics (QED) and Breit corrections into account has been adopted for calculations. Radiative data are reported for electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2), and magnetic quadrupole (M2) transitions from the ground level, although calculations have been performed for a much larger number of levels. To assess the accuracy of results, we performed analogous calculations using flexible atomic code (FAC). Comparisons are made with existing available results and a good agreement has been achieved. Most of the wavelengths calculated lie in the soft x-ray (SXR) region. Lifetimes for all 113 levels have also been provided for the first time. Additionally, we have provided the spectra for allowed transitions from n=2 to n= 3 within the x-ray region and also compared our SXR photon wavelengths with experimentally recognized wavelengths. We hope that our results will be beneficial in fusion plasma research and astrophysical applications.     

Cosmic (Super)String Constraints from 21 cm Radiation

We calculate the contribution of cosmic strings arising from a phase transition in the early Universe, or cosmic superstrings arising from brane inflation, to the cosmic 21 cm power spectrum at redshifts z > or =30. Future experiments can exploit this effect to constrain the cosmic string tension G mu and probe virtually the entire brane inflation model space allowed by current observations. Although current experiments with a collecting area of approximately 1 km2 will not provide any useful constraints, future experiments with a collecting area of 10(4)-10(6) km2 covering the cleanest 10% of the sky can, in principle, constrain cosmic strings with tension G mu > or = 10(-10)-10(-12) (superstring/phase transition mass scale >10(13) GeV).     

Investigations on Anticancer Potentials by DNA Binding and Cytotoxicity Studies for Newly Synthesized and Characterized Imidazolidine and Thiazolidine-Based Isatin Derivatives

Imidazolidine and thiazolidine-based isatin derivatives (IST-01–04) were synthesized, characterized, and tested for their interactions with ds-DNA. Theoretical and experimental findings showed good compatibility and indicated compound–DNA binding by mixed mode of interactions. The evaluated binding parameters, i.e., binding constant (K_b), free energy change (ΔG), and binding site sizes (n), inferred comparatively greater and more spontaneous binding interactions of IST-02 and then IST-04 with the DNA, among all compounds tested under physiological pH and temperature (7.4, 37 °C). The cytotoxic activity of all compounds was assessed against HeLa (cervical carcinoma), MCF-7 (breast carcinoma), and HuH-7 (liver carcinoma), as well as normal HEK-293 (human embryonic kidney) cell lines. Among all compounds, IST-02 and 04 were found to be cytotoxic against HuH-7 cell lines with percentage cell toxicity of 75% and 66%, respectively, at 500 ng/µL dosage. Moreover, HEK-293 cells exhibit tolerance to the increasing drug concentration, suggesting these two compounds are less cytotoxic against normal cell lines compared to cancer cell lines. Hence, both DNA binding and cytotoxicity studies proved imidazolidine (IST-02) and thiazolidine (IST-04)-based isatin derivatives as potent anticancer drug candidates among which imidazolidine (IST-02) is comparatively the more promising.     

Some properties of BLUE in a linear model and canonical correlations associated with linear transformations

Let (x, Xβ, V) be a linear model and let A′ = (A′₁, A′₂) be a p × p nonsingular matrix such that A₂X = 0, Rank A₂ = p − Rank X. We represent the BLUE and its covariance matrix in alternative forms under the conditions that the number of unit canonical correlations between y₁ ( = A₁x) and y₂ ( = A₂x) is zero. For the second problem, let x′ = (x′₁, x′₂) and let a g-inverse V⁻ of V be written as (V⁻)′ = (A′₁, A′₂). We investigate the reations (if any) between the nonzero canonical correlations {1 ₁ … ₁ > 0} due to y₁ ( = A₁x) and y₂ ( = A₂x), and the nonzero canonical correlations {1 λ₁ … λ_v+r > 0} due to x₁ and x₂. We answer some of the questions raised by Latour et al. (1987, in Proceedings, 2nd Int. Tampere Conf. Statist. (T. Pukkila and S. Puntanen, Eds.), Univ. of Tampere, Finland) in the case of the Moore-Penrose inverse V⁺ = (A′₁, A′₂) of V.     

Inferences on interclass and intraclass correlations in multivariate familial data

Inference procedures for interelass and intraclass correlations are given in the multivariate context of familial data for which measurements are taken on more than one characteristic. Unified estimators are proposed based on a certain class of unbiased estimators of covariance matrices. Asymptotic distributions of the proposed estimators are derived under the assumption of multivariate normality. The results can be used to construct approximate confidence intervals and test procedures.Research supported by the Department of Statistics, the Pennsylvania State University and the Air Force Office of Scientific Research under Grant AFSO-88-0030.Institute of Statistical Mathematics