Comment on "PT Symmetry as a Generalization of Hermiticity" [arXiv:1002.2676]

We notice that the general PT-symmetric Hamiltonian matrix(N=2) having 6-real parameters fails to reproduce one parameter PT-symmetric matrix.Comment: Title unchanged ,one ref [5] added . Abstract changed . All the previous matrices have been changed consideing the ref[5

Necessary and sufficient conditions for the oscillation of higher-order differential equations involving distributed delays

In this article, we establish necessary and sufficient conditions for the oscillation of both bounded and unbounded solutions of the differential equation \begin{equation} \bigg[x(t)+\int_{0}^{\lambda}p(t,v)x(\tau(t,v))\,\mathrm{d}v\bigg]^{(n)}+\int_{0}^{\lambda}q(t,v)x(\sigma(t,v))\,\mathrm{d}v=\varphi(t)\quad\text{for } t \geq t_{0},\notag \end{equation} where $n\in\mathbb{N}$, $t_{0},\lambda\in\mathbb{R}^{+}$, $p\in C([t_{0},\infty)\times[0,\lambda] \mathbb{R})$, $q\in C([t_{0},\infty)\times[0,\lambda],\mathbb{R}^{+})$, $\tau\in C([t_{0},\infty)\times[0 \lambda],\mathbb{R})$ with $\lim_{t\to\infty}\inf_{v\in[0,\lambda]}\tau(t,v)=\infty$ and $\sup_{v\in[0,\lambda]}\tau(t,v)\leq t$ for all $t\geq t_{0}$, $\sigma\in C([t_{0},\infty)\times[0,\lambda],\mathbb{R})$ with $\lim_{t\to\infty}\inf_{v\in[0,\lambda]}\sigma(t,v)=\infty$, and $\varphi\in C([t_{0},\infty),\mathbb{R})$. We also give illustrating examples to show the applicability of these results

NEUROPROTECTIVE EFFECT OF METHANOLIC EXTRACT OF SARGASSUM WIGHTII ON HALOPERIDOL INDUCED CATALEPSY AND TARDIVE DYSKINESIA IN ALBINO RATS

Objective: The present study was designed to evaluate the neuroprotective effect of methanolic extract of Sargassum wightii on haloperidol-induced catalepsy and tardive dyskinesia in Wistar albino rats. Methods: In this study, thirty Wistar albino rats were randomly divided into six groups. Gr-I served as control. Haloperidol (1 mg/kg intraperitoneally) was administered to rats of Gr-II to Gr-V for twenty-one consecutive days to induce catalepsy and tardive dyskinesia. Animals of Gr-II to Gr-V were orally administered with vehicle, levodopa carbidopa combination (30 mg/kg), Sargassum extract 200 and 400 mg/kg respectively. All the drugs and vehicles were given orally one hour before haloperidol injection for twenty one consecutive days. The cataleptic scores were recorded using standard bar test. Tardive dyskinesia was assessed in terms of vacuous chewing movement (VCM) and tongue protrusion (TP) scores. After behavioural testing, all animals were sacrificed on twenty-second day and various biochemical parameters like MDA, SOD and GSH were estimated in brain tissue. Results: Chronic administration of haloperidol significantly increased cataleptic scores, VCM and TP scores. (p<0.001) Sargassum wightii extract (400 mg/kg) significantly inhibited haloperidol-induced catalepsy, VCM and TP (p<0.001) Haloperidol increased MDA and decreased SOD and GSH in brain tissue to a highly significant extent (p<0.001) Sargassum extract at 400 mg/kg also significantly reversed the haloperidol-induced alteration in brain oxidative stress markers. Conclusion: Sargassum wightii inhibits haloperidol-induced catalepsy and tardive dyskinesia. Thus it may be used as a unique therapeutic adjunct for the prevention of neuroleptic-induced extrapyramidal symptoms, however, it has to be explored more

Evolution of microstructure and optical properties of TiO2/Au nanocomposite

TiO2/Au nanocomposite has been synthesized by mixing Au with milled TiO2 nanopowder through wet chemical route. The effect of Au on the microstructural and optical properties of TiO2 nanopowder has been studied by XRD, FESEM, UV Visible, PL and FTIR techniques. Our study indicates that Au causes the decrease of crystallite size of TiO2 by accumulating on the circumference of these nanoparticles. TiO2/Au nanocomposite exhibits strong spectral response in the visible range due to the surface plasmon effect. Band gap of TiO2 nanopowder reduces from 3.4 eV to 3.1 eV while making composite with Au. The PL spectra showed that emission peak intensity of TiO2 nanopowder decreases in the presence of Au. The reductions in band gap and electron-hole recombination in TiO2/Au nanocomposite suggest that TiO2/Au could be a good candidate for photocatalysis