Comparison of the metabolism of two floodplain lakes of the Trombetas River (Pará, Brazil) based on a study of diel variation

The diel variation of temperature, pH, electrical conductivity, dissolved oxygen concentration and chlorophyll-a was investigated in Batata and Mussurá Lakes on the Trombetas River floodplain. The diel variation of temperature was distinct in both lakes. The water column of Batata lake was completely mixed after 22ºº hour and Mussurá lake developed a well stablished gradient of temperature (differences up to 5.6 °C between surface and depth) which persisted all over the period studied. The thermal behavior determined the diet variation of the other parameters studied, which presented a homogenous vertical distribution in Batata Lake and remained stratified in Mussurá Lake. Chlorophyll-a concentrations were considerably lower in Batata Lake (1.8 µg/l) than in Mussurá Lake (10.8 µg/l) and resulted in production values (measured by oxygen diel variation) of ca. 2.6 g O2*m⁻²*d⁻¹ the first and 18.2 g O2*m⁻²*d⁻¹ in the former one

Careers Boundaries in the Arts in Brazil: An Exploratory Study

Over the last years the scholarly literature on careers has been enriched by the proposal of new career models which present a rhetoric that asks for the end of career boundaries: individual, hierarchical, organizational and geographical. However, in the real world, many constrains continue to exist. This paper tries to contribute to the understanding of the new boundaries of the 21st century careers. To do so we look at the case of careers in the arts. We review existing literature on careers, present a historical, contextual perspective of artistic careers, and conduct field work in the city of São Paulo based on in-depth interviews with 18 Brazilian artists from nine different occupations in the field of arts, whose data were subjected to qualitative content analysis. Our results show that career boundaries exist even in a sector we could consider as historically boundaryless . We identify and discuss four boundaries of the artistic career, seeking to reflect on the importance of considering the relationship of the individual and the context in which he/she operates in order to understand careers today

Concepciones de futuros profesores del primer ciclo de primaria sobre la naturaleza de la ciencia : contribuciones de la formación inicial

Research studies have showen that the image of science that students construct during their formal learning is strongly influenced by the teacher's conceptions about the nature of scientific knowledge. It is then fundamental to investigate the impact of initial teacher's education in the development of those conceptions in future teachers. The aim of this article is to present a study about the contribution of the three year initial teacher education, of basic education teachers (1st cycle - 6/10 years olds), in the development of their conceptions about the nature of science. The results show that the initial teacher education, as it has been developed in teacher training institutions, does not significantly influence the ideas held by future teachers about the nature of science

Bugs as Features (Part II): A Perspective on Enriching Microbiome-Gut-Brain Axis Analyses with Multidisciplinary Techniques

The microbiome-gut-brain-axis field is multidisciplinary, benefiting from the expertise of microbiology, ecology, psychiatry, computational biology, and epidemiology amongst other disciplines. As the field matures and moves beyond a basic demonstration of its relevance, it is critical that study design and analysis are robust and foster reproducibility. In this companion piece to Bugs as Features (Part 1), we present techniques from adjacent and disparate fields to enrich and inform the analysis of microbiome-gut-brain-axis data. Emerging techniques built specifically for the microbiome-gut-brain axis are also demonstrated. All of these methods are contextualised to inform several common challenges: how do we establish causality? How can we integrate data from multiple 'omics techniques? How might we account for the dynamicism of host-microbiome interactions? This perspective is offered to experienced and emerging microbiome scientists alike, to assist with these questions and others, at the study conception, design, analysis and interpretation stages of research.Comment: For main text: 20 pages, 2 figures; for supplementary analysis: 31 pages and 6 figures. Supplementary analysis generated using Rmarkdown by Thomaz F. S. Bastiaanssen. arXiv admin note: substantial text overlap with arXiv:2207.1247

Bugs as Features (Part I): Concepts and Foundations for the Compositional Data Analysis of the Microbiome-Gut-Brain Axis

There has been a growing acknowledgement of the involvement of the gut microbiome - the collection of microbes that reside in our gut - in regulating our mood and behaviour. This phenomenon is referred to as the microbiome-gut-brain axis. While our techniques to measure the presence and abundance of these microbes have been steadily improving, the analysis of microbiome data is non-trivial. Here, we present a perspective on the concepts and foundations of data analysis and interpretation of microbiome experiments with a focus on the microbiome-gut-brain axis domain. We give an overview of foundational considerations prior to commencing analysis alongside the core microbiome analysis approaches of alpha diversity, beta diversity, differential feature abundance and functional inference. We emphasize the compositional data analysis (CoDA) paradigm. Further, this perspective features an extensive and heavily annotated microbiome analysis in R in the supplementary materials, as a resource for new and experienced bioinformaticians alike.Comment: For main text: 23 pages, 3 figures; for supplementary demonstration analysis: 31 pages and 12 figures. Supplementary demonstration analysis generated using Rmarkdown by Thomaz F. S. Bastiaanssen. Part I of a two-part piec

Temperature and deuteration effects on the fluorescence of benzenoid solutions

Deuterium isotope substitution and temperature effects on the fluorescence of toluene and p-xylene solutions have been investigated. Values of fluorescence quantum yields were measured between -80° to 70°C for p-xylene, p-xylene d 10 , toluene and toluene- d 8 and also fluorescence decay times at room temperature. The influence of several experimental factors on the fluorescence intensity at various temperatures was investigated and corrections were applied to obtain correct quantum yields. The results are compatible with an absence of a normal deuteration effect, and are independent of temperature, for both molecules, and show the existence of a non-radiative transition from the first excited single state to the ground state.info:eu-repo/semantics/publishedVersio

Temperature effects on fluorescence quantum efficiency of 9,10-diphenylanthracene

The fluorescence quantum efficiency of 9,10-diphenylanthracene in ethanol was measured with very dilute solutions (not more than 5 × 10 -6 M), between 170 and 350 K, relative to solutions at room temperature. The results are compatible with a quantum efficiency of 0.88 at room temperature, which increases to 1.00 for temperatures below 190 K.North Atlantic Treaty Organization (NATO)info:eu-repo/semantics/publishedVersio

Mining the microbiome for markers of microbiota-gut brain communication and mental health

There has been a growing acknowledgement of the involvement of the gut microbiome - the collection of microbes that reside in our gut - in regulating our mood and behaviour. This phenomenon is referred to as the microbiota-gut-brain axis. While our techniques to measure the presence and abundance of these microbes has been steadily improving, there are many factors that prevent us from understanding what aspects of the gut microbiome specifically influence the microbiota-gut-brain axis. In this thesis, we set out to identify and investigate aspects of the microbiome that are informative to gut-brain communication. We do this by investigating the state of the gut microbiome in both health and disease, as well as after supplementing or perturbing it. While all of the work presented here is based on real data from real experiments, the thesis has a strong bioinformatics focus, that means that while the physiological background and interpretation are important, my role in these projects has been to bioinformatically and statistically zoom in on the features of the microbiome that are the most informative to our questions. As such, all results will be discussed from a primarily bioinformatics point of view. Two main aspects of the gut microbiome came out as the most promising features to measure, namely functional capacity and volatility. Traditionally, the microbiome is thought of as a collection of microbes and most analysis is done on the taxonomical level. However, we find that by investigating microbial function - as defined by the genes that are found or associated in the detected microbes - rather than taxonomy, we are able to perform more sensitive analysis and that our results are more easily interpretable. Second, microbiome studies are typically conducted using a single sample per subject. We find that the degree of change in the microbial ecosystem, called volatility, is an important feature of the microbiome and that is linked to severity of stress response. While volatility was coined before in the context of the microbiome, this was only in passing. We were the first to investigate volatility as a feature of the microbiome. Our research in this thesis reconfirms the existence of the microbiota-gut-brain axis and demonstrates novel metrics that can be used to interrogate the microbiome. We utilize mathematical frameworks originally from geology and classical ecology to bolster our analysis. We show that considering the microbiome as an ecosystem is a powerful model that can help us better formulate our scientific questions and interpret our findings. We argue for strategies to unify bioinformatics methodology in the microbiome-gut-brain axis field in an effort to move towards mechanistic understanding