Partition coefficients from water to organic solvents for phenoxide anions have been obtained using a method based on the variation of pK(a) of phenols with solvent. From these partition coefficients, the Abraham descriptors for phenoxide anions, on the same scale as descriptors for neutral molecules, have been obtained. Equations have been constructed for the prediction of descriptors, and val...

An experimental investigation on shape retrieval using Quadratic Polynomial Interpolation of Adjacent Landmarks (QPIAL), a newly proposed shape refinement method [1], is carried. Shape representation is a fundamental issue in the process of shape retrieval, a category of Content-Based Image Retrieval (CBIR). Many shape representations and shape refinement methods have been proposed. Fourier Des...

There are many methods to localize its position based on visual sensing schemes in indoor environment. This paper presents the problem of finding the correspondences of images feature’s descriptors when the images have large rotation. SIFT and SURF have always been considered as very effective algorithms to extract interest points and their orientation and descriptors. For descriptors, one of b...

The paper reports an improved method of content-based image retrieval using a well-known method of bag-of words (BoW). Words built over descriptors of popular affine-invariant keypoint detectors (Harris-Affine and Hessian-Affine are exemplary choices) are used. What is novel, however, is the number of descriptors (i.e. the number of words) representing individual keypoints. Instead of SIFT (or ...

A set of 21 mutagenic aliphatic N-nitrosamines were subjected to a pattern recognition analysis using ADAPT software. Four descriptors based on molecular connectivity, geometry and sigma charge on nitrogen were capable of achieving a 100% classification using the linear learning machine or iterative least squares algorithms. Three descriptors were capable of a 90.5% and two descriptors of a 85....

Quantitative structure–activity relationships (QSARs) and quantitative structure–property relationships (QSPRs) rely on regression equations containing numerical descriptors of molecular structure. In constructing these models, highly correlated descriptors are sometimes excluded from the regression equations. Although this exclusion seems reasonable, in fact it can lead investigators to overlo...

We have investigated techniques for distinguishing between drugs and nondrugs using a set of molecular descriptors derived from semiempirical molecular orbital (AM1) calculations. The "drug" data set of 2105 compounds was derived from the World Drug Index (WDI) using a procedure designed to select real drugs. The "nondrug" data set was the Maybridge database. We have first investigated the dime...

In designing microstructural materials systems, one of the key research questions is how to represent the microstructural design space quantitatively using a descriptor set that is sufficient yet small enough to be tractable. Existing approaches describe complex microstructures either using a small set of descriptors that lack sufficient level of details, or using generic high order microstruct...

OBJECTIVE To develop a set of descriptive terms applied to the sensation of dyspnea (dyspnea descriptors) for use in Brazil and to investigate the usefulness of these descriptors in four distinct clinical conditions that can be accompanied by dyspnea. METHODS We collected 111 dyspnea descriptors from 67 patients and 10 health professionals. These descriptors were analyzed and reduced to 15 ba...