982 research outputs found
Species richness and beta-diversity of aquatic macrophytes assemblages in three floodplain tropical lagoons: evaluating the effects of sampling size and depth gradients
Using aquatic macrophyte data gathered in three lagoons of the Paraná River floodplain we showed a strong effect of sample size on species richness. Incidence-based species richness estimators (Chao 2, jackknife 1, jackknife 2, incidence-based coverage estimator and bootstrap) were compared to evaluate their performance in estimating the species richness throughout transect sampling rnethod. Our results suggest that the best estimate of the species richness was gave by jackknife 2 estimator. Nevertheless, the transect sampling design was considered inappropriate to estimate aquatic macrophytes species richness. Depth gradient was not a good predictor of the species richness and species turnover (beta diversity). The dynamics of these environments, subject to high water-level fluctuation prevents the formation and permanence of a clear floristic depth-related gradient
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
Análise de logs do sistema Agritempo por meio do log do PHPNuke e WebAlizer.
O foco deste trabalho é a análise dos logs do sistema Agritempo, um sistema de monitoramento agrometeorológico que disponibiliza informações meteorológicas e agrometeorológicas de diferentes regiões brasileiras gratuitamente na internet3. O Agritempo possui um amplo público-alvo: produtores, extensionistas, consultores, agentes do governo, estudantes e professores universitários, além da iniciativa privada
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
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