Type O pure radiation metrics with a cosmological constant

In this paper we complete the integration of the conformally flat pure radiation spacetimes with a non-zero cosmological constant $\Lambda$, and $\tau \ne 0$, by considering the case $\Lambda +\tau\bar\tau \ne 0$. This is a further demonstration of the power and suitability of the generalised invariant formalism (GIF) for spacetimes where only one null direction is picked out by the Riemann tensor. For these spacetimes, the GIF picks out a second null direction, (from the second derivative of the Riemann tensor) and once this spinor has been identified the calculations are transferred to the simpler GHP formalism, where the tetrad and metric are determined. The whole class of conformally flat pure radiation spacetimes with a non-zero cosmological constant (those found in this paper, together with those found earlier for the case $\Lambda +\tau\bar\tau = 0$) have a rich variety of subclasses with zero, one, two, three, four or five Killing vectors

Obtaining a class of Type O pure radiation metrics with a cosmological constant, using invariant operators

Using the generalised invariant formalism we derive a class of conformally flat spacetimes whose Ricci tensor has a pure radiation and a Ricci scalar component. The method used is a development of the methods used earlier for pure radiation spacetimes of Petrov types O and N respectively. In this paper we demonstrate how to handle, in the generalised invariant formalism, spacetimes with isotropy freedom and rich Killing vector structure. Once the spacetimes have been constructed, it is straightforward to deduce their Karlhede classification: the Karlhede algorithm terminates at the fourth derivative order, and the spacetimes all have one degree of null isotropy and three, four or five Killing vectors.Comment: 29 page

StemChecker: a web-based tool to discover and explore stemness signatures in gene sets

Stem cells present unique regenerative abilities, offering great potential for treatment of prevalent pathologies such as diabetes, neurodegenerative and heart diseases. Various research groups dedicated significant effort to identify sets of genes-so-called stemness signatures-considered essential to define stem cells. However, their usage has been hindered by the lack of comprehensive resources and easy-to-use tools. For this we developed StemChecker, a novel stemness analysis tool, based on the curation of nearly fifty published stemness signatures defined by gene expression, RNAi screens, Transcription Factor (TF) binding sites, literature reviews and computational approaches. StemChecker allows researchers to explore the presence of stemness signatures in user-defined gene sets, without carrying-out lengthy literature curation or data processing. To assist in exploring underlying regulatory mechanisms, we collected over 80 target gene sets of TFs associated with pluri- or multipotency. StemChecker presents an intuitive graphical display, as well as detailed statistical results in table format, which helps revealing transcriptionally regulatory programs, indicating the putative involvement of stemness-associated processes in diseases like cancer. Overall, StemChecker substantially expands the available repertoire of online tools, designed to assist the stem cell biology, developmental biology, regenerative medicine and human disease research community. StemChecker is freely accessible at http://stemchecker.sysbiolab.eu.Portuguese Fundacao para a Ciencia e Tecnologia (FCT) [RH/BPD/96890/2013, SFRH/BPD/70718/2010, PTDC/BIA/GEN/116519/2010, IF/00881/2013, PTDC/BIA-GEN/116519/2010]; Programa Doutoral ProRegeM-Mecanismos de Doenca e Medicina Regenerativa [PD/00117/2012]info:eu-repo/semantics/publishedVersio

UniHI 7: an enhanced database for retrieval and interactive analysis of human molecular interaction networks.

Unified Human Interactome (UniHI) (http://www.unihi.org) is a database for retrieval, analysis and visualization of human molecular interaction networks. Its primary aim is to provide a comprehensive and easy-to-use platform for network-based investigations to a wide community of researchers in biology and medicine. Here, we describe a major update (version 7) of the database previously featured in NAR Database Issue. UniHI 7 currently includes almost 350,000 molecular interactions between genes, proteins and drugs, as well as numerous other types of data such as gene expression and functional annotation. Multiple options for interactive filtering and highlighting of proteins can be employed to obtain more reliable and specific network structures. Expression and other genomic data can be uploaded by the user to examine local network structures. Additional built-in tools enable ready identification of known drug targets, as well as of biological processes, phenotypes and pathways enriched with network proteins. A distinctive feature of UniHI 7 is its user-friendly interface designed to be utilized in an intuitive manner, enabling researchers less acquainted with network analysis to perform state-of-the-art network-based investigations

Is anodal transcranial direct current stimulation a potential ergogenic resource for muscle strength and effort perception? A critical review

Nas últimas décadas, vários estudos estão investigando a dose-resposta ideal em termos de frequência, intensidade e volume de treinamento para alcançar o aumento da força muscular, tanto em atletas quanto em não atletas. A dose-resposta é fundamental para a prescrição do treinamento, uma vez que sua manipulação equivocada pode acarretar alto risco de desenvolvimento de lesões por esforços repetitivos, bem como pelo não desenvolvimento da força esperada. Em indivíduos com nível avançado de treinamento de força, é extremamente importante aumentar sua intensidade e volume de treinamento. Nesse sentido, com os avanços encontrados na área de treinamento de força e a necessidade de novas estratégias para otimizar ganhos de força, um novo método vem ganhando força na literatura, a estimulação transcraniana por corrente contínua (ETCC). Portanto, o objetivo deste estudo é analisar criticamente os efeitos do ETCC como potencial recurso ergogênico para a realização de força muscular e percepção de esforço, bem como se seu uso é ético ou não. Para tanto, foram pesquisadas as bases de dados Pubmed/Medline, ISI Web of Knowledge e Scielo, apenas em inglês, e com as palavras-chave: força muscular, resistência muscular, estimulação transcraniana por corrente contínua, ETCC. Nós comparamos o efeito do ETCC anódico (ETCC-a) com uma condição sham/controle nos resultados de ETCC para força muscular e percepção de esforço força muscular e percepção de esforço. Nenhum estudo menciona efeitos colaterais negativos da intervenção. Os dados mostram diferenças entre os estudos que investigam os estudos de avaliação da força muscular e resistência muscular, em termos do uso bem sucedido de ETCC. Estudos que investigaram a eficiência do ETCC na melhora da força muscular demonstraram efeitos positivos do ETCC-a em 66,7% dos parâmetros testados. Amaioria dos dados mostra consistentemente a influência do ETCC-a na força muscular, mas não no desempenho de resistênciaEn las últimas décadas, diversos estudios están investigando la dosis-respuesta ideal en cuanto a la frecuencia, intensidad y volumen de entrenamiento para alcanzar el aumento de fuerza muscular, sea en atletas y no atletas. La dosis-respuesta es fundamental para la prescripción de entrenamiento, pues su manipulación equivocada puede llevar a un alto de riesgo de desarrollo de lesiones por esfuerzo repetitivo, así como para el no desarrollo de la fuerza esperada. En sujetos con nivel avanzado de entrenamiento de fuerza es extremadamente importante aumentar su intensidad y volumen de entrenamiento. En este sentido, con los avances encontrados en el área de entrenamiento de fuerza y la necesidad de nuevas estrategias para optimizar las ganancias de fuerza, un nuevo método está ganando fuerza en la literatura, la estimulación transcraneal por corriente continua (ETCC). Por lo tanto, el objetivo del presente estudio es analizar de forma crítica los efectos de la ETCC como potencial recurso ergogénico al desempeño de fuerza muscular y percepción de esfuerzo, así como si su uso es ético o no. Por lo tanto, se realizó una búsqueda en las bases de datos Pubmed/Medline, ISI Web of Knowledge y Scielo, solamente en inglés y con las palabras clave: fuerza muscular, resistencia muscular, estimulación transcraneal de corriente continua, ETCC. Comparamos el efecto de la ETCC anódica (ETCC-a) a una condición sham/control sobre los resultados de la fuerza muscular y percepción de esfuerzo. Ningún estudio menciona efectos secundarios negativos de la intervención. Los datos muestran diferencias entre los estudios que investigan la fuerza muscular y los estudios de evaluación de resistencia muscular, en lo que se refiere al uso exitoso de la ETCC. Los estudios que investigan la eficiencia de la ETCC en la mejora de la fuerza muscular demuestran efectos positivos de la ETCC-a en el 66,7% de los parámetros probados. La mayoría de los datos muestran consistentemente influencia de la ETCC-a en la fuerza muscular, pero no en el rendimiento de resistencia.In the last decades, several studies are investigating the optimal dose-response in terms of frequency, intensity and volume of training to achieve increased muscle strength in both athletes and non-athletes. Dose-response is critical to the prescription of training, since its mismanagement may pose a high risk of developing repetitive strain injuries as well as failure to develop the expected strength. In individuals with advanced level of strength training, it is extremely important to increase their intensity and training volume. In this sense, with the advances in the area of strength training and the need for new strategies to optimize force gains, a new method is gaining strength in the literature, the transcranial direct current stimulation (tDCS). Therefore, the purpose of this study is to critically analyze the effects of tDCS as a potential ergogenic resource for achieving muscle strength and perceived exertion, as well as whether its use is ethical or not. To do so, we searched the databases Pubmed/Medline, ISI Web of Knowledge and Scielo, in English only, and with the keywords: muscle strength, muscular endurance, transcranial direct current stimulation, tDCS. We compared the effect of anodic tDCS (a-tDCS) with a sham/control condition on muscle strength and perceived exertion results. No study mentions the negative side effects of the intervention. The data show differences between studies investigating studies of muscle strength and muscle endurance in terms of the successful use of tDCS. Studies that investigated tDCS efficiency in improving muscle strength demonstrated positive effects of a-tDCS on 66.7% of the parameters tested. Most data consistently show the influence of a-tDCS on muscle strength, but not on resistance performance.info:eu-repo/semantics/publishedVersio

Validity And Reliability Of A Self-efficacy Expectancy Scale For Adherence To Antiretroviral Therapy For Parents And Carers Of Children And Adolescents With Hiv/aids [validação E Reprodutibilidade De Uma Escala De Auto-eficácia Para Adesão Ao Tratamento Anti-retroviral Em Pais Ou Cuidadores De Crianças E Adolescentes Vivendo Com Hiv/aids]

Objective: To validate and evaluate the reproducibility of a self-efficacy (SE) scale for adherence to antiretroviral therapy in children and adolescents with HIV/AIDS, taking into account the perspective of parents/guardians. Methods: The study was carried out at the Hospital-Dia, Centro de Referência e Treinamento em DST/AIDS (CRT/SP), in São Paulo, Brazil. The parents/guardians of 54 children and adolescents aged 6 months to 20 years were interviewed during routine consultations at our service. Data on SE were collected using the Self-Efficacy for Following Anti-Retroviral Prescription Scale, and SE scores were calculated in two different ways: factor analysis and a predefined formula. The scale's internal consistency was verified using Cronbach's α coefficient. Validity was tested by comparing the mean scores of a group of patients who did adhere to antiretroviral treatment with those of a group that did not (Mann-Whitney test) and by calculating the Spearman correlation coefficient for agreement between scores and clinical parameters. Reproducibility was verified using the Wilcoxon test, intraclass correlation coefficients (ricc) and Bland-Altman plots. Results: The SE scale demonstrated good internal consistency (α = 0.87) and good reproducibility (r icc = 0.69 and r icc = 0.75). In terms of validity, the SE scale was capable of differentiating adherent patients from those who did not adhere to their antiretroviral treatment (p = 0.002) and exhibited a significant correlation with CD4 counts (r = 0.28; p = 0.04). Conclusions: The SE scale can be used to assess adherence to antiretroviral therapy in children and adolescents with HIV/AIDS, taking into account the perspective of parents/carers. Copyright © 2008 by Sociedade Brasileira de Pediatria.8414146Matida, L.H., da Silva, M.H., Tayra, A., Succi, R.C., Gianna, M.C., Gonçalves, A., Prevention of mother-to-child transmission of HIV in São Paulo State, Brazil: An update (2005) AIDS, 19 (SUPPL. 4), pp. S37-S41Gibb, D.M., Goodall, R.L., Giacomet, V., McGee, L., Compagnucci, A., Lyall, H., Paediatric European Network for Treatment of Aids Steering Committee. Adherence to prescribed antiretroviral therapy in human immunodeficiency virus-infected children in the PENTA 5 trial (2003) Pediatr Infect Dis J, 22, pp. 56-62Pluciennik, A.M., (2003) Transmissão materno infantil do vírus da imunodeficiência humana adquirida: Quanto custa não prevenir [tese], , São Paulo: Faculdade de Saúde Pública da USP;Dyke, R.B.V., Lee, S., Johnson, G.M., Wiznia, A., Mohan, K., Stanley, K., Reported adherence as a determinant of response to highly active antiretroviral therapy in children who have human immunodeficiency virus infection (2002) Pediatrics, 109 (4), pp. 1-7Starace, F., Massa, A., Amico, K.R., Fisher, J.D., Adherence to antiretroviral therapy: An empirical test of the information-motivation-behavioral skills model (2006) Health Psychol, 25, pp. 153-162Shah, C.A., Adherence to high activity antiretroviral therapy (HAART) in pediatric patients infected with HIV: Issues and interventions (2007) Indian J Pediatr, 74, pp. 55-60Leite, J.C., Drachler, M.L., Centeno, M.O., Pinheiro, C.A., Silveira, V.L., Desenvolvimento de uma escala de auto-eficácia para adesão ao tratamento anti-retroviral. (2002) Psicol Reflex Crit, 15, pp. 121-133Bandura, A., Self-efficacy: Toward a unifying theory of behavioral change (1977) Psychol Rev, 84, pp. 191-215Gortmaker SL, Lenderking WR, Clark C, Lee S, Fowler MG, Oleske JMThe ACTG 219 Team. Development and use of a pediatric quality of life questionnaire in AIDS clinical trials: reliability and validity of the general health assessment for children. In: Drotar D. Measuring health-related quality of life in children and adolescents: implications for research and practice. Mahwah, NJ: Lawrence Erlbaum Associates1998. p. 219-35Eiser, C., Morse, R., Quality-of-life measures in chronic diseases of childhood (2001) Health Technol Assess, 5, pp. 1-95Streiner, D.L., Norman, G.R., (2003) Health measurement scales: A practical guide to their development and use, , 3rd ed. Oxford: Oxford University Press;Drotar D, Levi R. Critical issues and needs in health-related quality of life assessment of children and adolescents with chronic health condition. In: Drotar D. Measuring health-related quality of life in children and adolescents: implications for research and practice. Mahwah, NJ: Lawrence Erlbaum Associates1998. p. 3-2

Extreme Ultra-Violet Spectroscopy of the Lower Solar Atmosphere During Solar Flares

The extreme ultraviolet portion of the solar spectrum contains a wealth of diagnostic tools for probing the lower solar atmosphere in response to an injection of energy, particularly during the impulsive phase of solar flares. These include temperature and density sensitive line ratios, Doppler shifted emission lines and nonthermal broadening, abundance measurements, differential emission measure profiles, and continuum temperatures and energetics, among others. In this paper I shall review some of the advances made in recent years using these techniques, focusing primarily on studies that have utilized data from Hinode/EIS and SDO/EVE, while also providing some historical background and a summary of future spectroscopic instrumentation.Comment: 34 pages, 8 figures. Submitted to Solar Physics as part of the Topical Issue on Solar and Stellar Flare