Gravitational quasinormal modes of AdS black branes in d spacetime dimensions

The AdS/CFT duality has established a mapping between quantities in the bulk AdS black-hole physics and observables in a boundary finite-temperature field theory. Such a relationship appears to be valid for an arbitrary number of spacetime dimensions, extrapolating the original formulations of Maldacena's correspondence. In the same sense properties like the hydrodynamic behavior of AdS black-hole fluctuations have been proved to be universal. We investigate in this work the complete quasinormal spectra of gravitational perturbations of $d$-dimensional plane-symmetric AdS black holes (black branes). Holographically the frequencies of the quasinormal modes correspond to the poles of two-point correlation functions of the field-theory stress-energy tensor. The important issue of the correct boundary condition to be imposed on the gauge-invariant perturbation fields at the AdS boundary is studied and elucidated in a fully $d$-dimensional context. We obtain the dispersion relations of the first few modes in the low-, intermediate- and high-wavenumber regimes. The sound-wave (shear-mode) behavior of scalar (vector)-type low-frequency quasinormal mode is analytically and numerically confirmed. These results are found employing both a power series method and a direct numerical integration scheme.Comment: added references, typos corrected, minor changes, final version for JHE

Performance of Coded Wireless Power Controllers for Wind Turbines Connected to a Smart Grid

Nowadays, with the advance of smart grid technologies, the participation of renewable energy in the power systems is changing for attend new requirements and increase efficiency of the systems. With a view of smart grid context, this work proposes the review of a modern wireless control system proposed based on for squirrel cage induction generators connected to the power grid. The wireless communication system applied transmits the reference power signals to the SCIG controller with the necessary reliability to ensure the power quality provided by the wind turbine employing the OFDM multi-carrier transmission technique associated with an LDPC coding scheme. The satisfactory results of this research endorse the operability and advantages of application of wireless control system for windy plants when some requirements and techniques, based on digital modulation and coding techniques, are employees

Genomics and epidemiology for gastric adenocarcinomas (GE4GAC): a Brazilian initiative to study gastric cancer

Abstract Gastric cancer (GC) is the fifth most common type of cancer worldwide with high incidences in Asia, Central, and South American countries. This patchy distribution means that GC studies are neglected by large research centers from developed countries. The need for further understanding of this complex disease, including the local importance of epidemiological factors and the rich ancestral admixture found in Brazil, stimulated the implementation of the GE4GAC project. GE4GAC aims to embrace epidemiological, clinical, molecular and microbiological data from Brazilian controls and patients with malignant and pre-malignant gastric disease. In this letter, we summarize the main goals of the project, including subject and sample accrual and current findings

Sexual and gender minorities rights in Latin America and the Caribbean: a multi-country evaluation

Abstract Background Although the extent of legal inequities experienced by sexual and gender minorities (SGM) has declined during recent decades, this population still enjoys fewer legal protections and benefits than the non-gender-variant, heterosexual population. Herein we analyze the current scenario of SGM rights in Latin America and the Caribbean (LAC). Methods Policy documents and governmental strategies addressing SGM rights were analyzed within a timeline framework by three major LAC sub-regions: the Caribbean, Mesoamerica and South America. Results Our search identified 88 eligible documents addressing the following categories: (1) legal protections towards same-sex couples (decriminalization of same-sex acts among consenting adults, legal recognition of same-sex unions, same-sex marriage, adoption by same-sex couples), and (2) anti-discrimination laws (SGM allowed to serve openly in the military and anti-discrimination laws related to sexual orientation, gender identity and/or expression). The majority of Caribbean countries prohibit same-sex acts between consenting adults, while in Mesoamerica same-sex couples do not have equal marriage rights and are not allowed to adopt as a couple. In the Caribbean and Mesoamerica transgender people lack proper legal protection. Legislation to protect SGM rights in South America is the most inclusive and progressive in LAC. Several countries recognize same-sex marriage and the right of transgender people to legally change their name and gender. The majority of South American countries have some kind of anti-discrimination law, but no effective mechanisms to enforce these laws. In spite of those progresses, the LAC region registers the highest rate of violence and hate crimes against SGM in the world. Conclusion In the Caribbean and Mesoamerica the overall discriminatory legislation exacerbates violence against SGM within a social and cultural context of strong sexist, gender stereotypes and widespread violence. This scenario is driving hundreds of SGM to leave their home countries. In spite of progressive legislations, several South American countries are currently controlled either by highly conservative leaders (e.g. Brazil and Chile) or by repressive dictators (Venezuela). The near future of the LAC region is unknown, but if such trends continue, severe human rights problems, including setbacks in SGM legal protections, are likely

Does immunity after Zika virus infection cross-protect against dengue?

Zika and dengue viruses are closely related flaviviruses, with immunological interactions and identical urban, mosquito-borne transmission.1Therefore, the recent introduction of Zika virus into the Americas and large-scale exposure of a uniformly previously unexposed population could affect subsequent transmission of dengue virus. This hypothesis had been untested, largely because sufficient epidemiological data were not available from affected locations. We explored this hypothesis in Salvador, the fourth largest city in Brazil (population 2·9 million), where extensive transmission of dengue viruses 1–42,3occurred before the introduction and spread of Zika virus in 2015.Fil: Ribeiro, Guilherme Sousa. Universidade Federal da Bahia; Brasil. Fundación Oswaldo Cruz; BrasilFil: Kikuti, Mariana. Fundación Oswaldo Cruz; Brasil. Universidade Federal da Bahia; BrasilFil: Tauro, Laura Beatriz. Fundación Oswaldo Cruz; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú; ArgentinaFil: Nascimento, Leile Camila J.. Fundación Oswaldo Cruz; BrasilFil: Cardoso, Cristiane W.. Secretaria Municipal de Saúde de Salvador; BrasilFil: Campos, Gúbio S.. Universidade Federal da Bahia; BrasilFil: Ko, Albert I.. Fundación Oswaldo Cruz; Brasil. University of Yale; Estados UnidosFil: Weaver, Scott C.. University of Texas Medical Branch; Estados UnidosFil: Reis, Mitermayer G.. Fundación Oswaldo Cruz; Brasil. Universidade Federal da Bahia; BrasilFil: Kitron, Uriel D.. University of Emory; Estados Unidos. Fundación Oswaldo Cruz; BrasilFil: Paploski, Igor A. D.. Universidade Federal da Bahia; BrasilFil: Silva, Monaise M. O.. Fundación Oswaldo Cruz; BrasilFil: Kasper, Amelia M.. Universidade Federal da Bahia; BrasilFil: Tavares, Aline S.. Fundación Oswaldo Cruz; BrasilFil: Cruz, Jaqueline S.. Fundación Oswaldo Cruz; BrasilFil: Moreira, Patrícia S. S.. Universidade Federal da Bahia; BrasilFil: Anjos, Rosângela O.. Fundación Oswaldo Cruz; BrasilFil: Araújo, Josélio M. G.. Universidade Federal do Rio Grande do Norte; BrasilFil: Khouri, Ricardo. Fundación Oswaldo Cruz; BrasilFil: Sardi, Silvia I.. Universidade Federal da Bahia; Brasi