23 research outputs found
La trayectoria de una reforma educativa global: el caso de la Nueva GestiĂłn PĂșblica en el sistema educativo catalĂĄn
Webometrics benefitting from web mining? An investigation of methods and applications of two research fields
Webometrics and web mining are two fields where research is focused on quantitative analyses of the web. This literature review outlines definitions of the fields, and then focuses on their methods and applications. It also discusses the potential of closer contact and collaboration between them. A key difference between the fields is that webometrics has focused on exploratory studies, whereas web mining has been dominated by studies focusing on development of methods and algorithms. Differences in type of data can also be seen, with webometrics more focused on analyses of the structure of the web and web mining more focused on web content and usage, even though both fields have been embracing the possibilities of user generated content. It is concluded that research problems where big data is needed can benefit from collaboration between webometricians, with their tradition of exploratory studies, and web miners, with their tradition of developing methods and algorithms
Ecological relevance of strigolactones in nutrient uptake and other abiotic stresses, and in plant-microbe interactions below-ground
El campo de las ciencias y la educaciĂłn superior entre el monopolio del inglĂ©s y el plurilingĂŒismo: elementos para una polĂtica del lenguaje en AmĂ©rica Latina
Calidad estival de las aguas en los rĂos influenciados por la ciudad de LeĂłn. Importancia de bioindicadores artrĂłpodos
A partir de la informaciĂłn obtenida en los muestreos de macroinvertebrados bĂ©nticos en diez estaciones en los rĂos Bernesga y TorĂo y en las proximidades de la ciudad de LeĂłn, se ha realizado un anĂĄlisis cuantitativo que permite llegar a establecer, a partir de Ăndices biĂłticos, la calidad del agu
How many replicates to accurately estimate fish biodiversity using environmental DNA on coral reefs?
Quantifying fish species diversity in rich tropical marine environments remains challenging. Environmental DNA (eDNA) metabarcoding is a promising tool to face this challenge through the filtering, amplification, and sequencing of DNA traces from water samples. However, because eDNA concentration is low in marine environments, the reliability of eDNA to detect species diversity can be limited. Using an eDNA metabarcoding approach to identify fish Molecular Taxonomic Units (MOTUs) with a single 12S marker, we aimed to assess how the number of sampling replicates and filtered water volume affect biodiversity estimates. We used a paired sampling design of 30 L per replicate on 68 reef transects from 8 sites in 3 tropical regions. We quantified local and regional sampling variability by comparing MOTU richness, compositional turnover, and compositional nestedness. We found strong turnover of MOTUs between replicated pairs of samples undertaken in the same location, time, and conditions. Paired samples contained non-overlapping assemblages rather than subsets of one another. As a result, non-saturated localized diversity accumulation curves suggest that even 6 replicates (180 L) in the same location can underestimate local diversity (for an area <1 km). However, sampling regional diversity using ~25 replicates in variable locations (often covering 10 s of km) often saturated biodiversity accumulation curves. Our results demonstrate variability of diversity estimates possibly arising from heterogeneous distribution of eDNA in seawater, highly skewed frequencies of eDNA traces per MOTU, in addition to variability in eDNA processing. This high compositional variability has consequences for using eDNA to monitor temporal and spatial biodiversity changes in local assemblages. Avoiding false-negative detections in future biomonitoring efforts requires increasing replicates or sampled water volume to better inform management of marine biodiversity using eDNA
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Representation and inclusion among members and affiliates of the Society for Epidemiologic Research: Findings from the 2021 Diversity and Inclusion Survey
Diverse representation and inclusion are stated priorities for scientific institutions and professional
societies, including the Society for Epidemiologic Research (SER). Prior studies have reported
persistent underrepresentation and exclusion of marginalized groups across the sciences. We
conducted a representation and inclusion survey among SER affiliates in 2021, following up on a
similar 2018 survey. In 2021, we observed broad representation from diverse groups across multiple
dimensions. However, across both surveys we found persistent underrepresentation of several
marginalized groups, including Black or African American and Hispanic/Latinx people. Some
groups reported feeling excluded in both the 2018 and 2021 surveys, and there was
disproportionately high representation from a subset of higher-ranked US academic institutions. For
several indicators of inclusion, perceptions of inclusion were more positive among White
respondents compared to other respondents. Opportunities to work towards achieving SERâs
diversity and inclusion aims include increasing outreach to epidemiology trainees and Minority
Serving Institutions, addressing cultural and financial barriers to participation, and improving access
for epidemiologists with disabilities. Iterative follow-up work with diversity and inclusion scholars
could improve our understanding of barriers to diversity and inclusion within SER and, more
broadly, the field of epidemiology