Engines of liberation

women;technological change

Ladder operators for isospectral oscillators

We present, for the isospectral family of oscillator Hamiltonians, a systematic procedure for constructing raising and lowering operators satisfying any prescribed `distorted' Heisenberg algebra (including the $q$-generalization). This is done by means of an operator transformation implemented by a shift operator. The latter is obtained by solving an appropriate partial isometry condition in the Hilbert space. Formal representations of the non-local operators concerned are given in terms of pseudo-differential operators. Using the new annihilation operators, new classes of coherent states are constructed for isospectral oscillator Hamiltonians. The corresponding Fock-Bargmann representations are also considered, with specific reference to the order of the entire function family in each case.Comment: 13 page

Use of vibrational spectroscopy to study 1,3-dimethyl-5-nitrobenzene: A combined theoretical and experimental approach

The FTIR and FT-Raman spectra of 1,3-dimethyl-5-nitrobenzene (DMNB) have been recorded in the range 4000‒400 cm−1 and 3500‒100 cm−1, respectively. The molecular structures, fundamental vibrational frequencies and intensity of the vibrational bands have been investigated and interpreted theoretically with the use of structural optimizations and normal coordinate force field calculations based on density functional theory (DFT) with 6-31G(d,p) basis set. The vibrational assignments have been made from potential energy distribution (PED). The theoretically simulated vibrational spectra of the molecule show excellent agreement with the experimental spectra. The hyper conjugative interaction energy (E(2)) and electron densities of donor (i) and acceptor (j) bonds have been calculated using NBO analysis. The electronic transition has been studied using UV-Visible analysis of the title molecule with B3LYP/6-31G(d,p) level of theory. The microscopic non-linear optical (NLO) behaviour of the title compound has also been calculated. In addition, the 1H and 13C NMR chemical shifts values of DMNB in the ground state for B3LYP/6-31G(d,p) method have also been calculated using gauge independent atomic orbital (GIAO) method

Beyond BAO: improving cosmological constraints from BOSS with measurement of the void-galaxy cross-correlation

We present a measurement of the anisotropic void-galaxy cross-correlation function in the CMASS galaxy sample of the BOSS DR12 data release. We perform a joint fit to the data for redshift space distortions (RSD) due to galaxy peculiar velocities and anisotropies due to the Alcock-Paczynski (AP) effect, for the first time using a velocity field reconstruction technique to remove the complicating effects of RSD in the void centre positions themselves. Fits to the void-galaxy function give a 1% measurement of the AP parameter combination $D_A(z)H(z)/c = 0.4367\pm 0.0045$ at redshift $z=0.57$, where $D_A$ is the angular diameter distance and $H$ the Hubble parameter, exceeding the precision obtainable from baryon acoustic oscillations (BAO) by a factor of ~3.5 and free of systematic errors. From voids alone we also obtain a 10% measure of the growth rate, $f\sigma_8(z=0.57)=0.501\pm0.051$. The parameter degeneracies are orthogonal to those obtained from galaxy clustering. Combining void information with that from BAO and galaxy RSD in the same CMASS sample, we measure $D_A(0.57)/r_s=9.383\pm 0.077$ (at 0.8% precision), $H(0.57)r_s=(14.05\pm 0.14)\;10^3$ kms$^{-1}$Mpc$^{-1}$ (1%) and $f\sigma_8=0.453\pm0.022$ (4.9%), consistent with cosmic microwave background (CMB) measurements from Planck. These represent a factor \sim2 improvement in precision over previous results through the inclusion of void information. Fitting a flat cosmological constant $\Lambda$CDM model to these results in combination with Planck CMB data, we find up to an 11% reduction in uncertainties on $H_0$ and $\Omega_m$ compared to use of the corresponding BOSS consensus values. Constraints on extended models with non-flat geometry and a dark energy of state that differs from $w=-1$ show an even greater improvement.Comment: 22 pages, 15 figures. Accepted for publication in Phys.Rev.D. v2 corrects small error in likelihood analysis; minor changes to figures and text, cosmological results unchanged. Reconstruction and void-finding code available at https://github.com/seshnadathur/Revolver, likelihood analysis code available at https://github.com/seshnadathur/void-galaxy-cosmo-fitte

Spectroscopic characterization and natural bond orbital analysis of 2-(trifluoromethyl) phenylacetonitrile based on DFT calculations

The experimental Fourier transform infrared (FT-IR) and Fourier transform Raman (FT-Raman) spectra of 2-(trifluoromethyl)phenylacetonitrile (2TFMP) have been recorded in the spectral region 4000‒400 cm−1 and 3500‒100 cm−1, respectively. Also the title molecule has been characterized by 13C NMR and 1H NMR spectroscopes. The geometry optimization and frequency calculations have been performed at B3LYP/6-311+G (d,p) level.  A detailed interpretation of FT-IR and FT-Raman spectra aided by the potential energy distributions (PEDs) for the calculated frequencies has been reported. Results of this study showed that there is a good correlation between the experimental and computational results. The HOMO-LUMO energy gap explains the charge transfer interactions in the molecule. NBO (natural bond orbital) computations have been utilized to evaluate the stabilities which occur from charge delocalization and inter-molecular interactions have been studied using DFT calculation

Topical steroid induced Cushing’s syndrome-a rare entity

The topical steroid therapy is the commonest mode of treatment for Psoriasis. When the therapy is overused, it can cause unusual side effects like Cushing’s syndrome which is very rarely reported and we are reporting such a case. Treatment with maintenance dose of steroids is necessary based on basal cortisol levels to avert hypocortisolemic crisis in Cushing’s syndrome, however in some select asymptomatic cases maintenance dose of steroids can be withdrawn and only stress dose be given in spite of low basal serum cortisol. We managed such a case and it is reported because of its rarity in clinical practice. This can alert the clinicians to avoid prescribing steroids as maintenance dose for a long time in asymptomatic Cushing’s syndrome with low morning cortisol and thereby reducing the side effects of long-term steroids on them

Dielectric anomalies and spiral magnetic order in CoCr2O4

We have investigated the structural, magnetic, thermodynamic, and dielectric properties of polycrystalline CoCr$_2$O$_4$, an insulating spinel exhibiting both ferrimagnetic and spiral magnetic structures. Below $T_c$ = 94 K the sample develops long-range ferrimagnetic order, and we attribute a sharp phase transition at $T_N$ $\approx$ 25 K with the onset of long-range spiral magnetic order. Neutron measurements confirm that while the structure remains cubic at 80 K and at 11 K; there is complex magnetic ordering by 11 K. Density functional theory supports the view of a ferrimagnetic semiconductor with magnetic interactions consistent with non-collinear ordering. Capacitance measurements on CoCr$_2$O$_4$, show a sharp decrease in the dielectric constant at $T_N$, but also an anomaly showing thermal hysteresis falling between approximately $T$ = 50 K and $T$ = 57 K. We tentatively attribute the appearance of this higher temperature dielectric anomaly to the development of \textit{short-range} spiral magnetic order, and discuss these results in the context of utilizing dielectric spectroscopy to investigate non-collinear short-range magnetic structures.Comment: & Figure