Explosive Nucleosynthesis: What we learned and what we still do not understand

This review touches on historical aspects, going back to the early days of nuclear astrophysics, initiated by B$^2$FH and Cameron, discusses (i) the required nuclear input from reaction rates and decay properties up to the nuclear equation of state, continues (ii) with the tools to perform nucleosynthesis calculations and (iii) early parametrized nucleosynthesis studies, before (iv) reliable stellar models became available for the late stages of stellar evolution. It passes then through (v) explosive environments from core-collapse supernovae to explosive events in binary systems (including type Ia supernovae and compact binary mergers), and finally (vi) discusses the role of all these nucleosynthesis production sites in the evolution of galaxies. The focus is put on the comparison of early ideas and present, very recent, understanding.Comment: 11 pages, to appear in Springer Proceedings in Physics (Proc. of Intl. Conf. "Nuclei in the Cosmos XV", LNGS Assergi, Italy, June 2018

Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches

Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly

Nucleosynthetic signatures of the first stars

Original article can be found at: http://www.nature.com/nature/index.html--Copyright Nature Publishing Group --DOI : 10.1038/nature03455Peer reviewe

Atribuição de falsas crenças no desenvolvimento de linguagem de crianças com síndrome de Down Attribution of false beliefs in the language development of children with Down syndrome

OBJETIVO: Avaliar atribuição de falsa crença em indivíduos com Síndrome de Down. MÉTODOS: Onze crianças usuárias de comunicação verbal, com síndrome de Down, retardo mental de grau leve a grave, de ambos os sexos, na faixa etária entre quatro e oito anos e atendidas em instituição compuseram o Grupo Down (GD). Além disso, 85 crianças sem alterações do desenvolvimento, na faixa etária entre quatro e seis anos, matriculadas em EMEI, constituíram o Grupo Controle (GC). Foram utilizados o Teste de Vocabulário por Imagem Peabody (TVIP) para a comparação do nível de compreensão verbal dos grupos, e o "teste dos smarties" adaptado, para avaliar a atribuição de falsa crença. RESULTADOS: Na análise do TVIP verificou-se diferença estatisticamente significante entre os grupos, sendo que o GD apresentou pontuação abaixo do terceiro desvio-padrão e, as crianças do GC, abaixo do primeiro desvio-padrão. Em relação à análise da atribuição de falsa crença, o GC apresentou progressão de acertos em todas as questões conforme o aumento da faixa etária. O mesmo não foi observado para o GD, sendo que os melhores resultados foram os dos indivíduos com maior tempo de terapia fonoaudiológica na instituição. Não houve correlação entre o nível de vocabulário receptivo e a habilidade de falsa crença. CONCLUSÃO: Em todas as questões houve melhor desempenho do GC em comparação ao GD. Sendo assim, foi possível analisar a falsa crença em crianças com síndrome de Down.<br>PURPOSE: To evaluate the attribution of false belief in individuals with Down syndrome. METHODS: Eleven children of both genders with Down syndrome and ages between four and eight years composed the Down Group (DG). All subjects used verbal communication, had mild to severe mental retardation, and were attended at the same institution. In addition, 85 children within normal development with ages between four and six years were recruited at an elementary school, constituting the Control Group (CG). The Peabody Picture Vocabulary Test (PPVT) was used to compare the level of verbal comprehension of the groups, and the adaptation of the "smarties test" was used to assess the attribution of false belief. RESULTS: The analysis of the PPVT showed a statistically significant difference between the groups, with the DG presenting scores below the third standard deviation, and the CG, below the first standard deviation. Regarding the false belief analysis, the CG presented increasing scores in all questions as the age group increased. The same was not observed for the DG, whose subjects with best results were those that attended speech-language therapy for a longer time at the institution. No correlation was found between receptive vocabulary level and the ability of false belief. CONCLUSION: The CG showed a better performance in all questions of the false belief test, when compared to the DG. Thus, it was possible to evaluate false belief in children with Down syndrome