The thermal dependence of optical and dielectric properties of one member namely 4 cyano-4(/)-n-nonyl biphenyl (code name 9CB) of the mesogenic homologous series of 4 cyano-4(/)-n-alkyl biphenyl (nCBs) is reported. The variation of orientational order parameter with temperature is determined and comparison made with theoretical Maier-Saupe values as well as the order parameter values of the other member of the series. The effect of temperature on the effective molecular dipole moment mu and the angle of inclination beta of the dipole axis with the preferred direction are investigated.

The electric quadrupole transition rates for the high spin yrast states of 104 Pd have been measured by using the DSAM technique. These values decrease with the increase of angular momentum which is a signature of anti-magnetic rotation. A numerical calcula- tion based on semi-classical particle plus rotor model for anti-magnetic rotation gives a good description of the experimental routhian and the transition rates. This is the first observation of AMR in a nucleus other than Cadmium.

The large aperture superferric quadrupole magnets i n energy buncher section of Super-FRS will generate h igh magnetic field gradient in the usable aperture. The magnet system will be assembled at room temperature and will undergo dissimilar thermal contraction dur ing operation at normal liquid helium temperature. It i s, therefore, very crucial from engineering design poi nt of view to understand and analyze both thermal and electromagnetic stress in coil, support structures and iron for its safe operation. The paper describes stress analysis of the magnet system as a whole with commercial FEM package ANSYS.

Environmental arsenic (As) is a potent human carcinogen and groundwater As contamination is a major health concern in West Bengal, India. Oxidative stress has been one of the prime factors in As-induced carcinogenicity. Generation of reactive oxygen species (ROS), beyond the body’s endogenous antioxidant balance cause a severe imbalance of the cellular antioxidant defence mechanism. Tea, a popular beverage has excellent chemopreventive and antioxidant properties. In this study it was investigated whether these flavonoids could ameliorate the arsenite (As III) induced oxidative stress in Swiss albino mice. Bio-monitoring with comet assay elicited that the increase in genotoxicity caused by As III was counteracted by both black tea and green tea. Elevated levels of lipid peroxides and protein carbonyl by As III were effectively reduced with green as well as black tea. They also exhibited protective action against the As III induced depletion of antioxidants like catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST) and glutathione (GSH) in mice liver tissue. Thus the tea polyphenols by virtue of their antioxidant potential may be used as an effective agent to reduce the As III induced oxidative stress in Swiss albino mice.

Undoped TiO2 and Ag–TiO2 (up to 23 at.% Ag) cermet thin films and polycrystalline powders have been prepared by sol–gel process. Their structure, composition, surface morphology and optical properties have been investigated by X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS) and ultraviolet–visible spectroscopy (UV–VIS spectroscopy). It has been observed that while Ag does not form a solid solution with TiO2, it promotes the anatase to rutile phase transformation. The transformation temperature decreases from 827 °C for undoped TiO2 to about 650 °C for 23 at.% Ag-doped TiO2. SIMS analyses show that Ag is mostly present on the surface of the films. XPS studies confirm that these Ag are in the Ag0 state. Optical analyses show that with increasing Ag content, the refractive index (n) increases and the optical absorption behavior of the cermet films is modified, but the band gap of the anatase TiO2 is not influenced.

The dynamics of electron loss to the continuum (ELC) from the light neutral projectile positronium (Ps) atom in collision with He+ ion is studied in the framework of post-collisional Eikonal approximation. The full three-body interaction, which is crucial for such ELC process is taken into account in the final channel. Both the triple differential cross sections (TDCS) and the double differential cross sections (DDCS) are studied at some intermediate and high incident energies, with respect to the threshold energy for this process. A distinct broad ELC peak centred around ve (velocity of the ejected electron) ≈vp (velocity of the positron) is noted in the ejected electron energy spectrum (DDCS) for forward ejection of e/e+, corroborating the experimental findings for the ELC process. The probability of emission of the e+ at higher angles is almost negligible as compared to its forward emission. Another salient feature noted in the present work is the shifting of the ELC DDCS (summed over the electron ejection angles) peak towards higher value of the ratio ve/vp with increasing incident energy, in agreement with the experimental findings of Armitage et al for Ps–He break-up process.

Undoped and up to 0.23at% Sn-doped TiO2 thin films and polycrystalline powders have been prepared by sol–gel process. Their structure, surface morphology and optical properties have been investigated by XRD, DTA–TG, SEM and UV–VIS spectroscopy. It has been observed that Sn promotes the anatase to rutile phase transformation and forms a complete solid solution with rutile TiO2. It is found that incorporation of about 0.17at% of Sn completely transforms anatase TiO2 to the rutile form at a calcination temperature as low as 500°C. This is the lowest temperature reported so far for the anatase to rutile phase transition in sol–gel TiO2. Optical analyses show that the Fermi level of the Ti1−xSnxO2 solid solutions increases with increasing x.

Genetically determined differences in immune responses to environmental agents may underlie susceptibility to many autoimmune and infectious diseases. Leprosy provides an example of a polarity in the type of immune response made to an infectious agent, and there is evidence that the major histocompatibility complex is genetically linked to leprosy type. It was found that HLA-DR2 is associated with both tuberculoid and lepromatous types of leprosy; however, a variant at position -308 of the promoter of the neighboring tumor necrosis factor (TNF) gene was increased in frequency in lepromatous (odds ratio = 3.0, P = .02) but not tuberculoid leprosy. Some studies have found higher serum levels of TNF in lepromatous than tuberculoid leprosy, and high TNF levels are found in malaria and leishmaniasis, which are also associated with this TNF allele. It is speculated that this association reflects genetic variability in cytokine production, which influences the immune response to and clinical outcome of leprosy.

Annalen der PhysikVolume 501, Issue 2 p. 141-143 Short Communication On the Non-Local Lie Backlund Symmetries and Prolongation Structure for a New Integrable System Swapna Roy, Swapna Roy High Energy Physics Division Department of Physics Jadavpur University Calcutta - 700 032, IndiaSearch for more papers by this authorDr. A. Roy Chowdhury, Dr. A. Roy Chowdhury High Energy Physics Division Department of Physics Jadavpur University Calcutta - 700 032, IndiaSearch for more papers by this author Swapna Roy, Swapna Roy High Energy Physics Division Department of Physics Jadavpur University Calcutta - 700 032, IndiaSearch for more papers by this authorDr. A. Roy Chowdhury, Dr. A. Roy Chowdhury High Energy Physics Division Department of Physics Jadavpur University Calcutta - 700 032, IndiaSearch for more papers by this author First published: 1989 https://doi.org/10.1002/andp.19895010210AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Volume501, Issue21989Pages 141-143 RelatedInformation

We have obtained compact expressions for the global solutions of the second order differential equations for the n-point conformal correlation functions. These equations were initially deduced by Belavin, Polyakov and Zamolodchikov. The monodromy property of such solutions can be ascertained from these expressions very easily.

We have reanalysed and reviewed the canonical structure associated with nonlinear integrable equations with emphasis on the mutual influence between the discrete and continuous spectrum. Our derivation explains the use of square eigenfunctions in the derivation of the symplectic structure. Actually we have illustrated the whole formalism on the basis of Derivative Nonlinear Schrödinger equation. It is really surprising to note that the usual approach to soliton-soliton scattering is not canonical. Furthermore an absolute separation of the discrete and continuous spectrum at least in case of DNLSE is not consistent. Our analysis really points out some basic difficulty in the framework Inverse Scattering Transform.

Bäcklund and Darboux–Bäcklund transformations are deduced for the superevaluation equations recently deduced by Kupershmidt [B. Kuperschmidt, ‘‘A super-K–dV equation—An integrable system,’’ preprint UTSI-Tullahoma, 1984; Phys. Lett. A 102, 213 (1983); J. Phys. A 17, L 863 (1984)] and Gürses [H. Gürses and O. Oguz, Phys. Lett. A 108, 437 (1985)]. By a extension of the technique of BPT [M. Boiti, F. Pempinelli, and G. Z. Tu, Nuovo Cimento B 79, 231 (1984)] to anticommuting variables the bi-Hamiltonian structure and hence the form of the recursion operator for the Lie–Bäcklund symmetry for such equations are deduced. Incidentally some explicit forms of the Lie–Bäcklund symmetry are also deduced.

We have considered the complete integrability of a class of nonlinear Klein-Gordon equation as equations—both autonomous and nonautonomous. The formalism employed is that of Ablowitz et al. It is observed that though inverse scattering equations exist for all of them yet one of them possesses fractional leading order singularity, signalling perhaps a weaker form of Painlevé property.

The authors have obtained the complete Lie-Backlund symmetry for a modified Harry-Dym system and hence deduced the bi-Hamiltonian structure associated with it. It is shown that these Lie-Backlund symmetries generate the recursion operator inherent in the theory and the conserved quantities can also be computed according to the Dorfman prescription.

We have developed a memory function approach to stochastic KdV equation. The behaviour of a KdV soliton and the corresponding many soliton solution are analyzed when under the influence of a random force obeying a Gaussian law of fluctuation. An interesting feature of our calculation is that in spite of the presence of the random perturbation, the solutions can be obtained and analyzed in an exact manner through the technique of memory function.