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The semi-arid districts of Tirunelveli and Tuticorin in the southern Indian state of Tamil Nadu consist of numerous wetlands in the form of irrigation tanks, interconnected by an ancient network of canals, and fed by the rivers originating from the Western Ghats. While these irrigation tanks have socio-economic and cultural significance, very little is known of their ecological importance. These tanks have the potential to harbor good populations of resident and wintering waterbirds but no studies have been done to confirm this. A survey was carried out in 230 irrigation tanks of various sizes in the two districts from November 2008 to January 2011. A total of 83 waterbird species were recorded. Indian Pond Heron Ardeola grayii occurred in most of the surveyed tanks. Large concentrations of wintering waterfowl such as Eurasian Wigeon Anas penelope, Northern Pintail Anas acuta, Garganey Anas querquedula were recorded in tanks closer to the coast. Based on our survey, six sites with large waterbird concentrations have been identified, one of which is Vagaikulam, an active heronry currently under threat from tree felling. These sites along with associated wetlands are important for the long term conservation of waterbirds in the region. [ABSTRACT FROM AUTHOR]

The experiment was conducted to evaluate the nutrient utilization ability of sweet orange (Citrus sinensis L. Osbeck) budded on five rootstocks (viz., Sathgudi, Rangpur lime, Cleopatra mandarin, Troyer citrange, and Trifoliate orange) in Alfisols at the experimental farm of the Citrus Improvement Project, S. V. Agricultural College Farm, Tirupati, Andhra Pradesh, India. Results of the study revealed that all the five rootstocks showed differential behaviors in terms of nutrient absorption from the soil. Rootstocks exhibited significant variation in the leaf content of potassium (K), copper (Cu), manganese (Mn), and boron (B) at all the three stages of sampling. Concentrations of the following key nutrient elements significantly varied: phosphorus (P), calcium (Ca), magnesium (Mg), zinc (Zn), and Cu at stage 1; K, Ca, Mg, Zn, iron (Fe), and Mn at stage 2; and nitrogen (N), P, Zn, Fe, and B at stage 3. The performances of rootstocks in terms of relative nutrient accumulation indices (RNAIs) were in the order of Sathgudi (1.00) > Rangpur lime (0.98) > Cleopatra mandarin (0.96) > Trifoliate orange (0.76) > Troyer citrange (0.69). The present study clearly demonstrated that citrus rootstocks employed had differential nutritional behavior and different abilities to utilize plant nutrient elements. Thus, the findings of the present study and the methodology adopted can help the horticultural breeders and nutritionists choose the best rootstock/scion combination having the desirable traits of nutrient utilization ability and also to plan effective fertilizer schedule programs for achieving greater yields. [ABSTRACT FROM PUBLISHER]

Anurans of Puducherry, a union territory measuring 293 km2, on the East coast of India are understudied. In this communication, we provide a comprehensive list of anurans encountered in and around wetlands across this union territory. Visual Encounter Surveys during the rainy season in 17 wetlands yielded a total of 14 species belonging to four families. This diversity is relatively low compared to other urban areas like Bangalore or Pune having 16 and 31 species respectively. Possible reasons for this low diversity and scope for future studies have been emphasized. [ABSTRACT FROM AUTHOR]

India has the largest population of patients with type 2 diabetes mellitus. The conventional agents used to treat type 2 diabetes frequently exhibit reduced efficacy over time leading to inadequate glycaemic control and are also associated with adverse effects. Hence, there is a need for alternative therapies that can overcome the limitations associated with conventional antidiabetic agents. This review focuses on Gliptins, which have become a research area of intense focus and present an alternative therapeutic strategy for patients with type 2 diabetes. Gliptins show significant improvements in glycaemic control and are well tolerated, particularly with regard to weight change and hypoglycemia. Hence, gliptins are considered as useful agents for the treatment of type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

A mixing rule is developed to predict extinction of a diffusion flame burning a multicomponent fuel. The chemical reaction is approximated as a one-step process between each component of the fuel and the oxidizer, and the activation energy characterizing the reaction is presumed to be large. The mixing rule predicts the overall chemical kinetic rate parameters characterizing the gas phase oxidation of the multicomponent fuel, if the rate parameters for its components are known. To test the validity of the predictions, extinction experiments were performed on diffusion flames stabilized above heptane, toluene, methanol, and a number of homogeneous solutions (with different proportions of the components) of these fuels. Experimental and theoretical values for the overall activation energy for the solutions were found to agree to better than 5 percent, and the preexponential factors were found to agree to better than a factor of three. [ABSTRACT FROM PUBLISHER]

Molecular constraints for the localization of active site directed ligands (competitive inhibitors and substrates) in the active site of phospholipase A2 (PLA2) are characterized. Structure activity relationships with known inhibitors suggest that the head group interactions dominate the selectivity as well as a substantial part of the affinity. The ab initio fitting of the amide ligands in the active site was carried out to characterize the head group interactions. Based on a systematic coordinate space search, formamide is docked with known experimental constraints such as coordination of the carbonyl group to Ca and hydrogen bond between amide nitrogen and ND1 of His48. An optimal position for a bound water molecule is identified and its significance for the catalytic mechanism is postulated. Unlike the traditional 'pseudo-triad' mechanism, the 'Ca-coordinated-oxyanion' mechanism proposed here invokes activation of the catalytic water to form the oxyanion in the coordination sphere of calcium. As it attacks the carbonyl carbon of the ester, a near-tetrahedral intermediate is formed. As the second proton of the catalytic water is abstracted by the ester oxygen, its reorientation and simultaneous cleavage form hydrogen bond with ND1 of His48. In this mechanism of esterolysis, a catalytic role for the water co-ordinated to Ca is recognised. [ABSTRACT FROM AUTHOR]