No abstract

The smectic layer thickness and the switching behavior in MHPOBC have been studied as a function of temperature; SmCα * is a tilted phase and is antiferroelectric at least in the higher-temperature region but becomes ferrielectric with decreasing temperature. The gradual appearance of ferrielectric characteristics in SmCα * suggests the emergence of the Devil's staircase. To explain the antiferroelectricity in SmCα * and SmCA *, two types of molecular interactions are proposed: one is the interaction between the spontaneous polarizations in the neighboring layers which is effective in SmCα *, and the other is the pairing of transverse dipole moments responsible for the antiferroelectricity in SmCA *.

A novel topological index, PI (Padmakar-Ivan index), is derived in this paper. The index is very simple to calculate and has disseminating power similar to that of the Wiener (W) and the Szeged (Sz) indices. The comprehensive studies show that the proposed PI index correlates highly with W and Sz as well as with physicochemical properties and biological activities of a large number of diversified and complex compounds. The proposed PI index promises to be a useful parameter in the QSPR/QSAR studies. The stability of each model is demonstrated by applying cross-validation test. Furthermore, more favorable comparison with other representative indices such as the Randic index is also made in order to establish the predictive ability of the PI index. The results have shown that in several cases the PI index gave better results.

No abstract

In this review we describe various applications of Szeged (Sz) index for modeling physicochemical properties as well as physiological activities of organic compounds acting as drugs or possess pharmacological activity.Keywords: Szeged index, physicochemical properties, biological activity, drug design, QSPR, QSAR, QSTR, multiple regression analysis. # On the eve of 70 th birthday of both Prof. Padmakar V. Khadikar and his wife Mrs. Kusum Khadikar.

Aluminum phosphide (ALP) poisoning is one of the major causes of suicidal deaths. Toxicity by ALP is caused by the liberation of phosphine gas, which rapidly causes cell hypoxia due to inhibition of oxidative phosphorylation, leading to circulatory failure. Treatment of ALP toxicity is mainly supportive as there is no specific antidote. We recently managed 7 cases of ALP poisoning with severe hemodynamic effects. Patients were treated with supportive measures including gastric lavage with diluted potassium permanganate, coconut oil and sodium-bicarbonate first person account should be avoided in a scientific paper. Intravenous magnesium sulfate, proper hemodynamic monitoring and vasopressors. Four out of 7 survived thus suggesting a role of such supportive measures in the absence of specific antidote for ALP poisoning.

No abstract

We have measured the temperature dependence of the infrared line shapes of three fundamental vibrations of the ethylidyne species, ≡C–CH3, on the Pt(111) surface. Each of the three line shapes possesses distinctly different properties. The C–C stretch shows the strongest temperature dependence. The full width at half-maximum (FWHM) varies quadratically with temperature from 6 cm−1 at 82 K to 10 cm−1 at 350 K. The frequency of the C–C stretch shows a linear shift from 1125 cm−1 at 82 K to 1117 cm−1 at 350 K. The symmetric C–H stretch shows a temperature independent frequency of 2883 cm−1 and only a small change in full width from 4.1 cm−1 at 82 K to 5.1 cm−1 at 300 K. The symmetric CH3 bend has an unusually narrow full width of 1.2 cm−1 at 82 K which increases to 2.4 cm−1 at 350 K while its frequency remains constant within the experimental error. The results are discussed in terms of current theories of vibrational line broadening for molecules adsorbed on metal surfaces.