Positronium Laser Cooling via the 1

We report on laser cooling of a large fraction of positronium (Ps) in free flight by strongly saturating the 1^{3}S-2^{3}P transition with a broadband, long-pulsed 243 nm alexandrite laser. The ground state Ps cloud is produced in a magnetic and electric field-free environment. We observe two different laser-induced effects. The first effect is an increase in the number of atoms in the ground state after the time Ps has spent in the long-lived 2^{3}P states. The second effect is one-dimensional Doppler cooling of Ps, reducing the cloud's temperature from 380(20) to 170(20) K. We demonstrate a 58(9)% increase in the fraction of Ps atoms with v_{1D}<3.7×10^{4} ms^{-1}.

Solvatochromic and single crystal studies of 3-(4-bromophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde.

The structure of 3-(4-bromophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde was determined by using X-ray diffraction analysis. Photophysical studies of the title compound were investigated in the solvents with different polarities. The emission spectrum of the compound was recorded in polar solvent DMSO (356 nm). In different solvents the extinction coefficients and quantum yield of the compound vary from 1.88×10(4) to 3.53×10(4) and 0.01 to 0.25, respectively. The ratio of the dipole moment of excited state to the dipole moment of ground state was calculated by using solvatochromic shift methods.

Synthesis, characterization and fluorescence studies of 3,5-diaryl substituted 2-pyrazolines.

A series of 2-pyrazolines have been synthesized from α, ß unsaturated ketones and hydrazine hydrate with acetic/formic acid in ethanol/DMSO. The structures of 2-pyrazolines have been established by spectroscopic techniques i.e. UV, IR, (1)H NMR, (13)C NMR and micro element analysis. Fluorescence spectra were recorded in the solution at fixed concentration and same excitation wavelength at 290 nm. The absorption band positions of all the compounds broadly lie between 280 and 336 nm and fluorescence band positions in the range between 300 and 370 nm, the near ultraviolet region.

Development and evaluation of pharmacosomes of aceclofenac.

Pharmacosomes are amphiphilic lipid vesicular systems containing phospholipid complexes with a potential to improve bioavailability of poorly water soluble as well as poorly lipophilic drugs. To improve the water solubility, bioavailability and minimize the gastrointestinal toxicity of aceclofenac, its pharmacosomes were prepared. Aceclofenac was complexed with phosphatidylcholine (80%) in two different ratios (1:1 and 2:1) using conventional solvent evaporation technique. Pharmacosomes thus prepared were subjected to solubility and drug content evaluation, scanning electron microscopy, differential scanning calorimetry, X ray powder diffraction and in vitro dissolution study. Pharmacosomes of aceclofenac were found to be disc shaped with rough surface in scanning electron microscopy. Drug content was found to be 91.88% (w/w) for aceclofenac phospholipid complex (1:1) and 89.03% (w/w) aceclofenac-phospholipid complex (2:1). Differential scanning calorimetric thermograms and X ray powder diffraction datas confirmed the formation of phospholipid complex. Solubility and dissolution profile of the prepared complex was found to be much better than aceclofenac.

Estimation of trace amounts of benzene in solvent-extracted vegetable oils and oil seed cakes.

A new method is presented for the qualitative and quantitative estimation of trace amounts (up to 0.15 ppm) of benzene in crude as well as refined vegetable oils obtained by extraction with food grade hexane (FGH), and in the oil seed cakes left after extraction. The method involves the selection of two solvents; cyclohexanol, for thinning of viscous vegetable oil, and heptane, for azeotroping out trace benzene as a concentrate from the resulting mixture. Benzene is then estimated in the resulting azeotrope either by UV spectroscopy or by GC-MS subject to availability and cost effectiveness of the latter. Repeatability and reproducibility of the method is within 1-3% error. This method is suitable for estimating benzene in vegetable oils and oil seed cakes.

Prevalence of ectoparasites on goats in Dehradun (India).

The prevalence of two phthirapteran species, Bovicola caprae and Linognathus africanus, on 1048 goats from Dehradun (India) was 79.2% and 38% respectively. Prevalence of both species was higher on visibly weaker and less hairy goats. Sex related differences in prevalence were not found. The prevalence of L. africanus was slightly higher on young goats but the same was not true in case of B. caprae. The incidence of B. caprae showed moderately negative correlation with environmental temperature and photoperiod. The relative intensity of B. caprae has been found higher during winter months, followed by summers. Study primarily deals with lice but the information about prevalence of other ectoparasites like ticks, fleas and keds, has also been supplemented.

Population structure of goat biting louse Bovicola caprae (Phthiraptera: Ischnocera).

The population structure of Bovicola caprae on goats has been recorded by examining 57 goatskins (45 by brushing cum searching and 12 by dissolving method). Population composition, sex ratio, adult nymph ratio has been recorded at different levels of infestation. The female dominated over the male population and male: female has been found to be 1:2 by brushing cum searching and 1:1.7 by dissolving method. Likewise, A:N was found to be 1:1.2 by brushing cum searching and 1:17 by dissolving method. The number of males and females follow similar pattern throughout population and were found to exhibit a high degree of correlation.

Incidence of Mallophaga on poultry in Dehradun (India).

The order of abundance of different mallophagan species on poultry birds in Dehradun (India) has been found to be Menopon gallinae greater than Menacanthus cornutus greater than Menacanthus stramineus greater than Goniocotes gallinae greater than Goniodes dissimilis greater than Lipeurus caponis greater than Lipeurus lawrensis tropicalis greater than Goniodes gigas. The intensity of these species upon 1249 birds has been recorded by coding system. The correlation between the monthly incidence of different species and environmental temperature as well as R.H. has been recorded. The degree of association between four most commonly occurring combinations has also been analysed.

Incidence of phthirapteran infestation upon the buffaloes of Dehradun (India).

Out of 373 buffaloes examined in different localities of Dehradun, 60.58% have been found infested with Haematopinus tuberculatus. Incidence of infestation was higher on adults than on youngs. The lice index was highest in January and lowest in June. The adults and nymphs preferred neck, back, ribs, shoulder, belly, thigh, hind, flank, head, hind legs, tail, fore legs and fore flank in this order of decreasing frequency. On the other hand eggs were found most heavily concentrated on neck and back regions.

The distribution of lice (Phthiraptera) on poultry (Gallus domesticus).

The distribution of three amblyceran (Menacanthus stramineus, Menacanthus cornutus, Menopon gallinae) and five ischnoceran species (Lipeurus lawrensis tropicalis, Lipeurus caponis. Goniocotes gallinae, Goniodes gigas, Goniodes dissimilis) on poultry was determined. The preferred sites of these species on the host body were recorded.