Pradesh (India).

In the present work, bio-conversion studies were performed on gallic acid, an important precursor for pharmaceutical industries engaged in manufacture of trimethoprim. Microbiological hydrolysis of two gallotanin rich substrates Chebulic myrobalan and Emblic myrobalan was studied by two fungal strains Aspergillus niger MTCC 281 and Rhizopus oryzae MTCC 1987. Comparative studies were performed using shake flask technique in different variations; high yield of gallic acid was produced by Aspergillus niger from Chebulic myrobalan. This article can be downloaded from www.ijpbs.ne

Measuring Distance and Properties of the Milky Way's Central Supermassive Black Hole with Stellar Orbits

We report new precision measurements of the properties of our Galaxy's supermassive black hole. Based on astrometric (1995-2007) and radial velocity (2000-2007) measurements from the W. M. Keck 10-meter telescopes, a fully unconstrained Keplerian orbit for the short period star S0-2 provides values for Ro of 8.0+-0.6 kpc, M_bh of 4.1+-0.6x10^6 Mo, and the black hole's radial velocity, which is consistent with zero with 30 km/s uncertainty. If the black hole is assumed to be at rest with respect to the Galaxy, we can further constrain the fit and obtain Ro = 8.4+-0.4 kpc and M_bh = 4.5+-0.4x10^6 Mo. More complex models constrain the extended dark mass distribution to be less than 3-4x10^5 Mo within 0.01 pc, ~100x higher than predictions from stellar and stellar remnant models. For all models, we identify transient astrometric shifts from source confusion and the assumptions regarding the black hole's radial motion as previously unrecognized limitations on orbital accuracy and the usefulness of fainter stars. Future astrometric and RV observations will remedy these effects. Our estimates of Ro and the Galaxy's local rotation speed, which it is derived from combining Ro with the apparent proper motion of Sgr A*, (theta0 = 229+-18 km/s), are compatible with measurements made using other methods. The increased black hole mass found in this study, compared to that determined using projected mass estimators, implies a longer period for the innermost stable orbit, longer resonant relaxation timescales for stars in the vicinity of the black hole and a better agreement with the M_bh-sigma relation.Comment: ApJ, accepted (26 pages, 16 figures, 7 tables

A New Technique for Finding Needles in Haystacks: A Geometric Approach to Distinguishing Between a New Source and Random Fluctuations

We propose a new test statistic based on a score process for determining the statistical significance of a putative signal that may be a small perturbation to a noisy experimental background. We derive the reference distribution for this score test statistic; it has an elegant geometrical interpretation as well as broad applicability. We illustrate the technique in the context of a model problem from high-energy particle physics. Monte Carlo experimental results confirm that the score test results in a significantly improved rate of signal detection.Comment: 5 pages, 4 figure

Genotoxic mechanisms for the carcinogenicity of the environmental pollutants and carcinogens o-anisidine and 2-nitroanisole follow from adducts generated by their metabolite N-(2-methoxyphenyl)-hydroxylamine with deoxyguanosine in DNA

An aromatic amine, o-anisidine (2-methoxyaniline) and its oxidative counterpart, 2-nitroanisole (2-methoxynitrobenzene), are the industrial and environmental pollutants causing tumors of the urinary bladder in rats and mice. Both carcinogens are activated to the same proximate carcinogenic metabolite, N-(2-methoxyphenyl)hydroxylamine, which spontaneously decomposes to nitrenium and/or carbenium ions responsible for formation of deoxyguanosine adducts in DNA in vitro and in vivo. In other words, generation of N-(2-methoxyphenyl)hydroxylamine is responsible for the genotoxic mechanisms of the o-anisidine and 2-nitroanisole carcinogenicity. Analogous enzymes of human and rat livers are capable of activating these carcinogens. Namely, human and rat cytochorme P4502E1 is the major enzyme oxidizing o-anisidine to N-(2-methoxyphenyl)hydroxylamine, while xanthine oxidase of both species reduces 2-nitroanisole to this metabolite. Likewise, O-demethylation of 2-nitroanisole, which is the detoxication pathway of its metabolism, is also catalyzed by the same human and rat enzyme, cytochorme P450 2E1. The results demonstrate that the rat is a suitable animal model mimicking the fate of both carcinogens in humans and suggest that both compounds are potential carcinogens also for humans

Is there an impact of public smoking bans on self-reported smoking status and exposure to secondhand smoke?

<p>Abstract</p> <p>Background</p> <p>Implementation of smoke free policies has potentially substantial effects on health by reducing secondhand smoke exposure. However little is known about whether the introduction of anti-smoking legislation translates into decreased secondhand smoke exposure. We examined whether smoking bans impact rates of secondhand smoke exposure in public places and rates of complete workplace smoking restriction.</p> <p>Methods</p> <p>Canadian Community Health Survey was used to obtain secondhand smoking exposure rates in 15 Ontario municipalities. Data analysis included descriptive summaries and 95% confidence intervals were calculated and compared across groups</p> <p>Results</p> <p>Across all studied municipalities, secondhand smoke exposure in public places decreased by 4.7% and workplace exposure decreased by 2.3% between the 2003 and 2005 survey years. The only jurisdiction to implement a full ban from no previous ban was also the only setting that experienced significant decreases in both individual exposure to secondhand smoke in a public place (-17.3%, 95% CI -22.8, -11.8) and workplace exposure (-18.1%, 95% CI -24.9, -11.3). Exposures in vehicles and homes declined in almost all settings over time.</p> <p>Conclusions</p> <p>Implementation of a full smoking ban was associated with the largest decreases in secondhand smoke exposure while partial bans and changes in existing bans had inconsistent effects. In addition to decreasing exposure in public places as would be expected from legislation, bans may have additional benefits by decreasing rates of current smokers and decreasing exposures to secondhand smoke in private settings.</p

Designing and Piloting a Tool for the Measurement of the Use of Pronunciation Learning Strategies

What appears to be indispensable to drive the field forward and ensure that research findings will be comparable across studies and provide a sound basis for feasible pedagogic proposals is to draw up a classification of PLS and design on that basis a valid and reliable data collection tool which could be employed to measure the use of these strategies in different groups of learners, correlate it with individual and contextual variables, and appraise the effects of training programs. In accordance with this rationale, the present paper represents an attempt to propose a tentative categorization of pronunciation learning strategies, adopting as a point of reference the existing taxonomies of strategic devices (i.e. O'Malley and Chamot 1990; Oxford 1990) and the instructional options teachers have at their disposal when dealing with elements of this language subsystem (e.g. Kelly 2000; Goodwin 2001). It also introduces a research instrument designed on the basis of the classification that shares a number of characteristics with Oxford's (1990) Strategy Inventory for Language Learning but, in contrast to it, includes both Likert-scale and open-ended items. The findings of a pilot study which involved 80 English Department students demonstrate that although the tool requires considerable refinement, it provides a useful point of departure for future research into PLS

Adult beginner distance language learner perceptions and use of assignment feedback

This qualitative study examines perceptions and use of assignment feedback among adult beginner modern foreign language learners on higher education distance learning courses. A survey of responses to feedback on assignments by 43 Open University students on beginner language courses in Spanish, French, and German indicated that respondents can be classified into three groups: those who use feedback strategically by integrating it into the learning process and comparing it with, for example, informal feedback from interaction with native speakers, those who take note of feedback, but seem not to use it strategically, and those who appear to take little account of either marks or feedback. The first group proved to be the most confident and most likely to maintain their motivation in the longer term. The conclusion discusses some of the pedagogical and policy implications of the findings

Parameterization of subgrid plume dilution for use in large-scale atmospheric simulations

A new model of plume dynamics has been developed for use as a subgrid model of plume dilution in a large-scale atmospheric simulation. The model uses mean wind, shear, and diffusion parameters derived from the local large-scale variables to advance the plume cross-sectional shape and area in time. Comparisons with a large eddy simulation of aircraft emission plume dynamics, with an analytical solution to the dynamics of a sheared Gaussian plume, and with measurements of aircraft exhaust plume dilution at cruise altitude show good agreement with these previous studies. We argue that the model also provides a reasonable approximation of line-shaped contrail dilution and give an example of how it can be applied in a global climate model

Study of Atmospheric Pollution Scavenging: Eighteenth Progress Report

published or submitted for publicationis peer reviewedOpe