Probing the Effects of Lorentz-Symmetry Violating Chern-Simons and Ricci-Cotton Terms in Higher Derivative Gravity

The combined effects of the Lorentz-symmetry violating Chern-Simons and Ricci-Cotton actions are investigated for the Einstein-Hilbert gravity in the second order formalism modified by higher derivative terms, and their consequences on the spectrum of excitations are analyzed. We follow the lines of previous works and build up an orthonormal basis of operators that splits the fundamental fields according to their individual degrees of freedom. With this new basis, the attainment of the propagators is remarkably simplified and the identification of the physical and unphysical modes gets a new insight. Our conclusion is that the only tachyon- and ghost-free model is the Einstein-Hilbert action added up by the Chern-Simons term with a time-like vector of the type $v^{\mu} = (\mu,\vec{0})$. Spectral consistency imposes taht the Ricci-Cotton term must be switched off. We then infer that gravity with Lorentz-symmetry violation imposes a drastically different constraint on the background if compared to usual gauge theories whenever conditions for suppression of tachyons and ghosts are required.Comment: 15 pages. It coincides with the version published in Phys. Rev.

Understanding the relationship between illness perceptions of breast cancer and perceived risk in a sample of U.A.E. female university students: the role of comparative risk

BackgroundIn the Middle East region, the incidence of breast cancer (BC) has substantially increased in the last years. Despite a considerable body of research about BC in Arab countries, how illness perceptions of healthy women about BC may influence risk perception is unknown.MethodsA cross-sectional survey was conducted on a sample of 298 young Emirati women. The measures included demographic information, illness perceptions, and risk perception. Descriptive and correlational analyses were performed to assess illness perceptions about BC, perceived individual risk and comparative risk. A structural equation modelling (S.E.M.) was built to investigate the relationship between illness perceptions and perceived individual risk.ResultsParticipants reported negative illness perceptions about BC The individual risk perception and the compared risk perception for BC were low. Participants with a family history of BC reported more negative illness and higher risk perceptions. The relationship between illness perceptions and perceived individual risk was significant and mediated by compared risk. The S.E.M. explained 55.9% of the variance in predicting perceived individual risk for BC.ConclusionWomen\u27s views of BC are important factors in risk perception and may provide culturally sensitive clues to promote early screening for BC in Arab countries. This may be important for policymakers to design intervention strategies to lower health risks, considering the different ways in which women perceive their risks for BC

Mixed-mode fracture and load misalignment on the assessment of FRP-concrete bond connections

Considerable dispersion is usually found in experimental data concerning the material properties of FRP-concrete bond connections. In pure shear models, the direction of FRP loading is assumed to be parallel to the axis of the concrete specimen. However, in practice, it is very difficult to prevent load misalignment. This fact can have important consequences on the derivation of material properties from experimental data. This is why a parametric study is herein undertaken to thoroughly identify the role of the load misalignment in the behaviour of the connection. It is concluded that the load capacity of the connection significantly decreases in the case of a misaligned load pointing outwards the reinforced surface. It is also found that this effect is less relevant for thick laminates when compared to thin FRP sheets.Australian Research Council Discovery Early Career Researcher Award (DE150101703); Faculty of Engineering & Information Technologie

Understanding the relationship between illness perceptions of breast cancer and perceived risk in a sample of U.A.E. female university students: the role of comparative risk

BMC Women's Health is an open access, peer-reviewed journal that considers articles on all aspects of the health and wellbeing of adolescent girls and women, with a particular focus on the physical, mental, and emotional health of women in developed and developing nations. The journal welcomes submissions on women's public health issues, health behaviours, breast cancer, gynecological diseases, mental health and health promotion.info:eu-repo/semantics/publishedVersio

How Do Healthy Women Perceive the Risk of Breast Cancer? The Role of Illness Perceptions and Compared Risk between Portugal and the U.A.E

(1) Background: Breast cancer (BC) shows significant epidemiological differences between Eastern and Western countries. These may arise from socio-cultural factors influencing how healthy young women perceive this condition, their risk of getting cancer, and the implications for preventive screening behaviors. In this study, the illness perceptions, individual risk perception, compared risk, and beliefs about preventive behaviors for BC of female university students were compared using an anonymous online survey between a European country (Portugal) and the United Arab Emirates. (2) Method: A structural equation model (SEM) was developed to investigate the hypothetical relationship between illness perceptions and compared risk as predictors of perceived risk for BC. (3) Results: There were significant differences between the study variables. The SEM was invariant, but the differences between regression coefficients in both countries were highly statistically significant. Mediation analyses revealed a significant indirect effect of compared risk on individual risk and a significantly stronger direct effect for the Emirati sample. (4) Conclusions: These findings suggest that cultural research may help to explain factors that may shape social comparison of individual risk characteristics and influence perceived risk. Moreover, providing culturally appropriate strategies to be designed and implemented can promote early detection behaviors for BC