Mining Antagonistic Communities From Social Networks

In this thesis, we examine the problem of mining antagonistic communities from social networks. In social networks, people with opposite opinions normally behave differently and form sub-communities each of which containing people sharing some common behaviors. In one scenario, people with opposite opinions show differences in their views on a set of items. Another scenario is people explicitly expressing whom they agree with, like or trust as well as whom they disagree with, dislike or distrust. We defined the indirect and direct antagonistic groups based on the two scenarios. We have developed algorithms to mine the two types of antagonistic groups. For indirect antagonistic group mining, our algorithm explores the search space of all the possible antagonistic groups starting from antagonistic groups of size two, followed by searching antagonistic groups of larger sizes. We have als

Long-term surveillance of mortality and cancer incidence in women receiving hormone replacement therapy

This paper reports the preliminary results of a cohort study of 4544 British women receiving hormone replacement therapy (HRT). These women were recruited at 21 specialist menopause clinics around Britain. Up to the end of June 1983, the mean duration of HRT use per woman was 67 months of which, on average, 43% was‘opposed’use. In general, however, both the amount of progestogen given and the number of days per cycle for which it was given was less than would have been the case if the women had been receiving modern opposed therapy. The major focus of the study was to monitor mortality and cancer incidence in the cohort. The mortality results were broadly reassuring: overall mortality was significantly lower than expected on the basis of national rates (relative risk 0·58) and mortality ratios were below unity for all specific causes of death examined apart from cancer of the ovary (relative risk 1·43, 95% confidence limits 0·62–2·82) and suicide or suspected suicide (relative risk 2·53, 95% confidence limits 1·26–4·54). The most likely explanation for the latter finding is selection bias—thus at least 7 of the 11 women who died from suicide or suspected suicide had a psychiatric history before receiving HRT. The cancer incidence results were less reassuring, although they should be interpreted with some caution because cancer registry rates were used for comparative purposes. With this proviso, endometrial cancer risk was significantly elevated (relative risk 2·84,95% confidence iimits 1·46–4·96); many of the women concerned had taken therapy which was predominantly or entirely opposed although only one woman had received an opposed regimen which would now be considered adequately protective to the endometrium. Breast cancer incidence was also significantly increased (relative risk 1·59, 95% confidence limits 1·18–2·10); detailed analysis suggested that the use of unopposed ethinyloestradiol in particular might have undesirable effects on the breast

Investigations on the defect structure and the EPR parameters for AgBr:Ir

The defect structure and the EPR parameters (the g factors, the hyperfine structure constants and the superhyperfine parameters) for the tetragonal Ir2+ center in AgBr are theoretically investigated using the perturbation formulas of these parameters for a 5d7 ion in tetragonally elongated octahedra. In the calculations, the contributions from the ligand orbital and spin-orbit coupling interactions and the local lattice (elongation) distortion due to the Jahn-Teller effect are taken into account. Related molecular orbital coefficients and the ligand unpaired spin densities are determined quantitatively using a cluster approach. The impurity center is attributed to the substitutional [ IrBr6] 4− cluster on host Ag+ site, which suffers the relative elongation of about 0.08 Å along C4 axis due to the Jahn-Teller effect. The calculated EPR parameters based on the above Jahn-Teller elongation show good agreement with the observed values

An NMR spectroscopic method to identifiy and classify thiol-trapping agents: revival of Michael acceptors for drug discovery?

Speed trap: Cysteamine reacts in DMSO with electrophilic double bonds to afford Michael adducts (see scheme), whereas no trapping reaction takes place in apolar solvents. A simple and quick NMR spectroscopic method to identify Michael acceptors and sort them into reversible and irreversible thiol sinks is validated biologically in a cellular assay sensitive to thiol-trapping agents