the significance of research article (ra) abstract as a key academic genre has recently motivated analysts to focus on this neglected area. considering a summary function for abstracts, most genre researchers have adopted the conventionally proposed introduction- method- results- discussion (or conclusion) (imrd) model for analysis. however, the problems reported, especially for results and dis...

to study the effect of different fertilizing systems on macro and micro nutrients uptake by annual medic (medicago scutellata cv. robinson) an experiment was conducted under dry farming and irrigated conditions at two research stations (sararood dryland agricultural research institute and soil fertility research station in mahidasht) during 2009 growing season. the experimental treatments consi...

Protein-ligand complexes are often consulted for the understanding of binding modes and mechanisms of action as well as the development of novel drugs. Unfortunately the resolution of most x-ray structures is too low to resolve hydrogen atoms. However, hydrogen positions play a major role in the analysis of important interaction types as hydrogen bonding or metal interactions. Therefore, it is ...

N-(pyridin-2-yl)thiazol-2-amine is a versatile chemical functional unit present in many therapeutically important species. Quantum chemical analysis shows that there are six competitive isomeric structures possible for this class of compounds within a relative energy difference of ∼4 kcal/mol. Some of the isomeric structures possess divalent N(I) character. There appears to be a competition bet...

the protonation constant values of salicylic and 5-nitrosalicylic acid werestudied by a combinationof spectrophotometric and potentiometric methods at 25 °c in wide range of ionic strength. the ionicstrength of solutions was kept constant by sodium perchlorate as background electrolyte at 0.10 to 3.0 moldm-3. potentiometer was calibrated according to gran method at each of ionic strength. the p...

2-Aminopurine (AP), a potent mutagenic base analogue, most frequently pairs with thymine. In the AP X T base pair, both bases adopt normal tautomeric forms. The mechanism for the mutagenic activity arises from its observed pairing with cytosine, which has been ascribed to an enhanced tendency to adopt the rare imino tautomeric form. NMR studies in H2O on all the exchangeable protons in an oligo...

In this paper we present our reworked approach to generate ligand protonation states with our structure preparation tool SPORES (Structure PrOtonation and REcognition System). SPORES can be used for the preprocessing of proteins and protein-ligand complexes as e.g. taken from the Protein Data Bank as well as for the setup of 3D ligand databases. It automatically assigns atom and bond types, gen...

ab initio and dft methods have been used to study the seven tautomeric forms of 5-methylcytosine molecule.the related tautomer in gas phase have been studied at hf/6-31g, hf/6-31g* and b3lyp/6-31g* levels oftheory. the structures,enthalpies,entropies,gibbs free energies,relative tautomerization energies of tautomersand tautomeric equilibrium constants were compared and analyzed along with full ...

The solute-solvent interactions of L-glutamic acid and L-methionine have been studied in 0–60% V/V 1,2-propanediolwater media using the pH-metric method. The protonation constants have been calculated with the computer program MINIQUAD75. Selection of the best fit chemical model of the acid-base equilibria is based on standard deviation in protonation constants and residual analysis using cryst...