Non-relativistic electron-electron interaction in a Maxwell-Chern-Simons-Proca model endowed with a timelike Lorentz-violating background

A planar Maxwell-Chern-Simons-Proca model endowed with a Lorentz-violating background is taken as framework to investigate the electron-electron interaction. The Dirac sector is introduced exhibiting a Yukawa and a minimal coupling with the scalar and the gauge fields, respectively. The the electron-electron interaction is then exactly evaluated as the Fourier transform of the Moller scattering amplitude (carried out in the non-relativistic limit) for the case of a purely time-like background. The interaction potential exhibits a totally screened behavior far from the origin as consequence of massive character of the physical mediators. The total interaction (scalar plus gauge potential) can always be attractive, revealing that this model may lead to the formation of electron-electron bound states.Comment: 14 pages, 4 figures, style revtex. To appear in International Journal Modern Physics

Lipkea ruspoliana Vogt, 1886 (Cnidaria: Staurozoa) in Portugal: the contribution of citizen science to range extension and taxonomic discussion of rare species

Citizen science online platforms are increasingly making important sources of biological information available at the click of a button, allowing the interaction of volunteers and scientists to report and identify the world's diversity. In this work, we combined the data available in citizen science platforms (iNaturalist and GelAvista) and the effort and collaboration of a diverse team of scuba-divers, scientists, and underwater photographers to report for the first time the presence of the stauromedusa Lipkea (Cnidaria: Staurozoa) in Portugal. Based on DNA (COI and 16S), we identified the species as Lipkearuspoliana. However, the marginal lappets of some Portuguese specimens are similar to those of Lipkeasturdzii, a species described based on a single specimen in 1893 and never reported again. These results suggest that L.sturdzii is a synonym of L.ruspoliana, although further taxon and habitat sampling for genetic studies and investigations of intraspecific morphological variation are necessary. In addition, we provided data on species ecology, reviewed the records of Staurozoa from Portugal, and mapped the world geographic distribution of Lipkea. Staurozoa is a cryptic group of cnidarians, and Lipkea seems to be a particularly rare genus. Citizen science has proved to be a valuable contribution to studies on the group, enabling biological discussions that otherwise would be more challenging.BIOMARES20212023; UID/MAR/04292/2018/2019; BiodivAMP Grant FA_06_2017_045; BiodivRestore ERA-NET Cofund (GA N°101003777); POCI-01-0247-FEDER-033889info:eu-repo/semantics/publishedVersio

Uma WebQuest como Tema Gerador para o Ensino de Análises Químicas

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Proposta de Webquest para a Introdução da Química dos Materiais no Contexto do Ensino Médio da Escola Pública

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A low-cost HPV immunochromatographic assay to detect high-grade cervical intraepithelial neoplasia

Objective To evaluate the reproducibility and accuracy of the HPV16/18-E6 test. Methods The study population was comprised of 448 women with a previously abnormal Pap who were referred to the Barretos Cancer Hospital (Brazil) for diagnosis and treatment. Two cervical samples were collected immediately before colposcopy, one for the hr-HPV-DNA test and cytology and the other for the HPV16/18-E6 test using high-affinity monoclonal antibodies (mAb). Women with a histologic diagnosis of cervical intraepithelial neoplasia grade 2 or 3 were considered to be positive cases. Different strategies using a combination of screening methods (HPV-DNA) and triage tests (cytology and HPV16/18-E6) were also examined and compared. Results The HPV16/18-E6 test exhibited a lower positivity rate compared with the HPV-DNA test (19.0% vs. 29.3%, p<0.001) and a moderate/high agreement (kappa = 0.68, 95% CI: 0.60-0.75). It also exhibited a significantly lower sensitivity for CIN2+ and CIN3+ detection compared to the HPV-DNA test and a significantly higher specificity. The HPV16/18-E6 test was no different from cytology in terms of sensitivity, but it exhibited a significantly higher specificity in comparison to ASCH+. A triage test after HPV-DNA detection using the HPV16/18-E6 test exhibited a significantly higher specificity compared with a triage test of ASCH+ to CIN2+ (91.8% vs. 87.4%, p = 0.04) and CIN3+ (88.6% vs. 84.0%, p = 0.05). Conclusion The HPV16/18-E6 test exhibited moderate/high agreement with the HPV-DNA test but lower sensitivity and higher specificity for the detection of CIN2+ and CIN3+. In addition, its performance was quite similar to cytology, but because of the structural design addressed for the detection of HPV16/18-E6 protein, the test can miss some CIN2/3+ lesions caused by other high-risk HPV types.Cancer Prevention Department, Center for the Researcher Support and Pathology Department of the Barretos Cancer Hospital. This study was supported by CNPq 573799/2008-3 and FAPESP 2008/57889-1info:eu-repo/semantics/publishedVersio

Personality Traits of an Entrepreneur, Determinants of Successful Microenterprise in Ireland

Why do certain individuals become entrepreneur and are successful, whereas others do not? The researchers in the entrepreneurship field attempt to answer that question by studying the personality traits of entrepreneurs for decades. Many confirm that the personality traits have a positive correlation with entrepreneurial intention and performance. Various studies suggest that the main entrepreneurial characteristics are risk attitudes, need for achievement, internal locus of control, innovativeness, and self-efficacy. However, debate exist if the personality traits are born or inherited and if the entrepreneurs’ actions are influenced by factors such as family, culture, education and market conditions. Although these aspects will be reviewed the focus of this study is on entrepreneurs’ personality traits only. Consequently, the aim of this study is to identify which of the personality traits, and whether there are traits, that are associated with operating successful microenterprise, from a perspective of an owner-manager of an established business in Ireland. The findings of this research revealed that the participants perceive themselves as individuals who possess indirectly four out of five most cited traits in the literature, which are need for achievement, locus of control, innovativeness and self-efficacy. In addition, they mentioned ability to relate to others, being organized and perform a quality work as the most important characteristics of a successful business owner. Also, other factors of environment influenced the participants’ decision to become an entrepreneur and Ireland was perceived as an attractive country to set up a business. Still, most of the participants do not perceive themselves as a successful entrepreneur. In summary, the inconclusiveness of this study generate more questions than it provide answers, coupled with this study limitations it is suggested that additional and more extensive research is desired