Adolescents in stepfamilies: Developmental family interventions.

Discusses issues and interventions for working with adolescents who live in stepfamilies. A developmental perspective, using psychoeducation and brief strategic intervention approaches, is proposed for working with stepfamilies. Six major issues for adolescents in stepfamilies are discussed: developmental issues, sexuality issues, parent–child relationships, parenting in stepfamilies, nonresidential parent–child issues, and changes in visitation and custody. Case illustrations and suggested interventions are presented for each of these areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Palliative treatments of cancers of upper respiratory and digestive tracts

Palliative treatment of head and neck cancers needs an initial evaluation based upon clinical symptoms and tumoral behaviour. Local recurrences are the most frequent presentation of tumoral failures. The therapeutic management of these local recurrences requires a mixture of unspecific and specific oncologic procedures. Radiotherapy and chemotherapy are frequently used in those circumstances in order to reduce the tumoral volume and to facilitate the effectiveness of unspecific treatments. Management of metastatic disease is often impaired by the moderate efficiency of chemotherapy while this treatment leads to marked side effects. Basically, the best therapeutic choice depends on the expected positive balance between the improvement of symptoms and the level of treatment-related side effects. However, daily clinical approach is a better way to care these patients than predefined rigid protocols.     

Randomization in individual choice behavior.

There is ample evidence that people cannot generate random series when instructed to do so. Rather, they produce sequences with too few symmetries and long runs and too many alternations among events. The authors propose a psychological theory to account for these findings, which assumes that subjects generate nonrandom sequences that locally represent theoretical random series subject to a constraint on their short-term memory. Closed-form expressions are then derived for the major statistics that have been used to test for deviations from randomness. Results from 3 experiments with 2 and 3 equiprobable alternatives support the model on both the individual and group levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fooling anti-virus systems

Anti-virus (AV) products and other fingerprint-based systems are typical of the applications used to enforce security. AV products are probably the first step that most organizations take to protect their systems and enhance security. Many small to medium organizations rely almost entirely on AV products.     

A Maximum Entropy Approach for Collaborative Filtering

Collaborative filtering (CF) involves predicting the preferences of a user for a set of items given partial knowledge of the user's preferences for other items, while leveraging a database of profiles for other users. CF has applications e.g. in predicting Web sites a person will visit and in recommending products. Fundamentally, CF is a pattern recognition task, but a formidable one, often involving a huge feature space, a large data set, and many missing features. Even more daunting is the fact that a CF inference engine must be capable of predicting any (user-selected) items, given any available set of partial knowledge on the user's other preferences. In other words, the model must be designed to solve any of a huge (combinatoric) set of possible inference tasks. CF techniques include memory-based, classification-based, and statistical modelling approaches. Among these, modelling approaches scale best with large data sets and are the most adept at handling missing features. The disadvantage of these methods lies in the statistical assumptions (e.g. feature independence), which may be unjustified. To address this shortcoming we propose a new model-based CF method, based on the maximum entropy principle. For the MS Web application, the new method is demonstrated to outperform a number of CF approaches, including naive Bayes and latent variable (cluster) models, support vector machines (SVMs), and the (Pearson) correlation method.     

Interfacial effects of surface-active agents under zinc pressure leach conditions

Liquid sulfur-zinc sulfate solution interfacial tensions and liquid sulfur-zinc sulfate solution-zinc sulfide (marmatite) contact angles were measured in the absence and presence of surface-active agents. Interfacial tensions measured varied between 54 ± 1 mN/m in the surfactant-free system and 20 ± 1 mN/m in the presence of a surfactant. The liquid sulfur-zinc sulfide mineral-zinc sulfate solution contact angle varies between 80 ± 5 deg, in the absence of any surfactant, and 148 ± 5 deg, depending on the surfactant used. The surface-active agents were used as dispersants for sulfur in bench-scale zinc pressure-leaching experiments. The observed extent of zinc extraction depends on the surfactant and varies from 40 to 96 pct.     

Confidentiality in psychotherapy: History, issues, and research.

Discusses ethical guidelines of the American Psychological Association regarding confidentiality in psychotherapy. Possible inconsistencies between these guidelines and privileged communication are explored. It is asserted that additional research is needed to determine the implications for psychotherapy of the ethical limitations to confidentiality and the legal restrictions on privileged communication. The relevance of moral philosophy to issues of confidentiality is considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Investigation of iron oxide reduction by TEM

An “environmental cell” located in a high voltage transmission electron microscope has been used to study the reduction of single crystal iron oxides by hydrogen and hydrogen-argon mixtures. The cell enables a direct observation of the solid during reaction, thus permitting the nucleation and growth of solid reaction products to be observed. Hematite was reduced at temperatures in the range 387 to 610°C with gas pressures up to 5.3 kP. Reduction with pure hydrogen was considerably faster than when argon was present. Lath magnetite which rapidly transforms to porous magnetite and thence (more slowly) to porous iron was observed. The reduction of magnetite and of wustite single crystals was observed in the temperature range 300 to 514°C using both hydrogen and hydrogen-argon mixtures at gas pressures up to 6.6 kP. Incubation periods were found for magnetite reduction; during these periods faceted pits formed in the oxide. Iron formed in the early stages was epitaxial with the host magnetite; at later stages the epitaxy was lost and fissures frequently formed in the metal. The morphology of the iron differed between the gas mixtures. Disproportionation accompanied the reduction of wustite, producing intermediate polycrystalline magnetite despite reducing conditions. The disproportionation appeared to be promoted by the reduction reaction. For both oxides, reduction in the hydrogen-argon mixture was slower than in pure hydrogen.