A new approach for analyzing the moleculedescriptor matrix for the QSAR problem (Quantitative StructureActivity Relationship) based on a fuzzy cluster structure of the learning sample is presented. The ways for generating fast rules for refusing prediction and searching the spikes in the learning sample are described. For this purpose, a special space of descriptors, simple for calculation, is ...

the cytotoxic chloroform fraction of euphorbia aellenii afforded two cycloartane type triterpenes — cycloart-25-en-3,24-diol (1) and 24-methylene-cycloartan-3-ol (2) — for the first time from this plant. preparation of cycloartane derivatives, 3, 24-o-diacetyl-cycloart-25-en as compound 3 and 3-o-acetyl-24-methylene-cycloartan (4) were conducted by acetylating of 1 and 2, respectively. the ...

Automatic change pattern mapping in urban and sub-urban area is important but challenging due to the diversity of urban land use pattern. With multi-sensor imagery, it is possible to generate multidimensional unique information of Earth surface features that allow developing a relationship between a response of each feature to synthetic aperture radar (SAR) and optical sensors to track the chan...

The species-area relationship (SAR) gives a quantitative description of the increasing number of species in a community with increasing area of habitat. In conservation, SARs have been used to predict the number of extinctions when the area of habitat is reduced. Such predictions are most needed for landscapes rather than for individual habitat fragments, but SAR-based predictions of extinction...

PURPOSE To examine relationships between specific energy absorption rate (SAR) and temperature distributions in the human head during radio frequency energy deposition in MRI. MATERIALS AND METHODS A multi-tissue numerical model of the head was developed that considered thermal conductivity, heat capacity, perfusion, heat of metabolism, electrical properties, and density. Calculations of SAR ...

We tackle the problem of automatic detection of StructureActivity relationships by means of Inductive Logic Programming (ILP). We describe an algorithm for constructing features from background knowledge (stochastic propositionalization SP) and an abstract level representation for chemical compounds.

The species-area relationship (SAR) provides a cornerstone for ecological theory. Implicit in SAR studies is the assumption that SAR properties, especially SAR slopes, remain constant through time, even though the ecosystem characteristics that they encompass the spatial distribution and abundance of species change on seasonal to evolutionary time scales. Focusing on disturbed subalpine systems...

C describe the concept of multimodal analgesia and give examples Abstract Opium is the natural substance to which modern narcotics owe their existence. First discovered in the 1500s, opium was the most potent analgesic compound in use, held in high regard, hence its Latin name laudanum (to praise). Subsequent studies into the effects of opium led to the discovery of the opioid receptors, and th...