New Singular and Nonsingular Colliding Wave Solutions in Einstein - Maxwell - Scalar Theory

A technique is given to generate coupled scalar field solutions in colliding Einstein - Maxwell (EM) waves. By employing the Bell - Szekeres solution as seed and depending on the chosen scalar field it is possible to construct nonsingular solutions. If the original EM solution is already singular addition of scalar fields does not make the physics any better. In particular, scalar field solution that is transformable to spherical symmetry is plagued with singularities.Comment: 15 pages, To be published in GR

Negative parental responses to coming out and family functioning in a sample of lesbian and gay young adults

Parental responses to youths' coming out (CO) are crucial to the subsequent adjustment of children and family. The present study investigated the negative parental reaction to the disclosure of same-sex attraction and the differences between maternal and paternal responses, as reported by their homosexual daughters and sons. Participants' perceptions of their parents' reactions (evaluated through the Perceived Parental Reactions Scale, PPRS), age at coming out, gender, parental political orientation, and religiosity involvement, the family functioning (assessed through the Family Adaptability and Cohesion Evaluation Scales, FACES IV), were assessed in 164 Italian gay and lesbian young adults. Pearson correlation coefficients were calculated to assess the relation between family functioning and parental reaction to CO. The paired sample t-test was used to compare mothers and fathers' scores on the PPRS. Hierarchical multiple regression was conducted to analyze the relevance of each variable. No differences were found between mothers and fathers in their reaction to the disclosure. The analysis showed that a negative reaction to coming out was predicted by parents' right-wing political conservatism, strong religious beliefs, and higher scores in the scales Rigid and Enmeshed. Findings confirm that a negative parental reaction is the result of poor family resources to face a stressful situation and a strong belief in traditional values. These results have important implications in both clinical and social fields

Strong guidance on mitigating the effects of uncertainties in the brass casting blending problem: a hybrid optimization approach

WOS: 000315819600007The scrap charge optimization problem in the brass casting process is a critical management concern that aims to reduce the charge while preventing specification violations. Uncertainties in scrap material compositions often cause violations in product standards. In this study, we have discussed the aleatory and epistemic uncertainties and modelled them by using probability and possibility distributions, respectively. Mathematical models including probabilistic and possibilistic parameters are generally solved by transforming one type of parameter into the other. However, the transformation processes have some handicaps such as knowledge losses or virtual information production. In this paper, we have proposed a new solution approach that needs no transformation process and so eliminates these handicaps. The proposed approach combines both chance-constrained stochastic programming and possibilistic programming. The solution of the numerical example has shown that the blending problem including probabilistic and possibilistic uncertainties can be successfully handled and solved by the proposed approach. Journal of the Operational Research Society (2013) 64, 562-576. doi:10.1057/jors.2012.5

User requirements regarding information included in audio-tactile maps for individuals with blindness

The aim of this study is to investigate the user requirements of young adults with blindness regarding the information to be included/ mapped in two different types of audio-tactile mobility maps: (a) audio-tactile maps of indoors, and (b) audio-tactile maps of campuses. Forty young adults (aged from 18 years to 30 years) with blindness took part in the research. Participants came from four countries: 14 from Greece, 2 from Cyprus, 18 from Turkey, and 6 from Germany. The researchers developed two lists of information to be included in the two types of audio-tactile maps (indoor and campus) respectively. Participants were asked to evaluate the information, regarding: (a) the significance of the information in regard to safety, location of services, way finding and orientation during movement, and (b) the frequency the participants meet the information (within their surrounding and the environment they move in). The first list of information to be evaluated, related to the maps of indoor places consisted of 136 different information, and the second list of information to be evaluated, related to the campus maps consisted of 213 different information. The result of the study is the definition of the most important information that should be included in each one of the two different types of audio-tactile maps. Thus, the findings of the present study will be particularly important for designers of orientation and mobility (O&M) aids for individuals with blindness. Moreover, the findings can be useful for O&M specialists, rehabilitation specialists, and teachers who design and construct O&M aids for their students with blindness. © Springer International Publishing Switzerland 2016