Search results for "network"

Benchmark database for fine-grained image classification of benthic macroinvertebrates

2018

Managing the water quality of freshwaters is a crucial task worldwide. One of the most used methods to biomonitor water quality is to sample benthic macroinvertebrate communities, in particular to examine the presence and proportion of certain species. This paper presents a benchmark database for automatic visual classification methods to evaluate their ability for distinguishing visually similar categories of aquatic macroinvertebrate taxa. We make publicly available a new database, containing 64 types of freshwater macroinvertebrates, ranging in number of images per category from 7 to 577. The database is divided into three datasets, varying in number of categories (64, 29, and 9 categori…

A multidisciplinary analytical framework to delineate spawning areas and quantify larval dispersal in coastal fish

2019

International audience; Assessing larval dispersal is essential to understand the structure and dynamics of marine populations. However, knowledge about early-life dispersal is sparse, and so is our understanding of the spawning process, perhaps the most obscure component of biphasic life cycles. Indeed, the poorly known species-specific spawning modality and early-life traits, along with the high spatio-temporal variability of the oceanic circulation experienced during larval drift, hamper our ability to properly appraise the realized connectivity of coastal fishes. Here, we propose an analytical framework which combines Lagrangian modeling, network theory, otolith analyses and biogeograph…

Environmental Challenges in the Philippines

2017

The Republic of the Philippines is one of most exposed countries in the world to many “natural” hazards: earthquakes, volcanic eruptions, tsunami, lahar flows, typhoons, flooding, landslides, and sea level rise. Earthquake risks make Metro Manila especially vulnerable, due to the high population density and the poor quality of buildings, partly linked to corruption. This chapter examines the current policies to reduce risk in the metropolis and the scales of vulnerability, both at the national, regional, community and individual levels, focusing on the resilience of people and society when confronted with danger. Their vulnerability is heightened with several forms of environmental degradat…

Structure and vulnerability of the multi‐interaction network in macrophyte‐dominated lakes

2019

The network approach is crucial to understand how ecosystems are structured and how they will respond to the disturbances (e.g. the current global change). We have recreated the multi‐interaction network of a shallow freshwater lake dominated by submerged macrophytes (Charophytes), a known system very vulnerable to environmental changes, considering both trophic and non‐trophic relationships among its elements. To minimize the environmental variability, we established it in an experimental mesocosm, including three habitats: the pelagic, the habitat around the meadow and the periphytic community living on macrophytes. We aimed to study the structure of this network and the roles of its elem…

2020

Abstract Facing the loss of biodiversity caused by landscape fragmentation, implementation of ecological networks to connect habitats is an important biodiversity conservation issue. It is necessary to develop easily reproducible methods to identify and prioritize actions to maintain or restore ecological corridors. To date, several competing methods are used with recurrent debate on which is best and if expert-based approaches can replace data-driven models. We compared three methods: knowledge-driven (expert based), data-driven (based on species distribution model), and a mixed approach. We quantified their differences in habitat and corridor mapping, and prioritizations of landscape elem…

Mechanisms of reciprocity and diversity in social networks: a modeling and comparative approach

2018

Individual-based computer models show that different mechanisms, proximity-based or emotional bookkeeping, can lead to reciprocation. By comparing social networks from different computer models with those of empirical data, we show that the models’ social networks bear limited resemblance with some features of the observed social networks. This indicates that additional social processes (third-party awareness) may be needed in these models to represent more accurately the social behavior and interaction patterns observed in group-living animals.

Innovative technologies for encapsulation of Mediterranean plants extracts

2017

Abstract Background High-added value biological compounds (BACs) from herbal and plant sources, such as essential oils (EO), antioxidants and volatile compounds, often exhibit remarkable features, ranging from nutritive and medicinal properties, as well as antimicrobial and antioxidant activities, which can be exploited in the production of functional foods. However, most BACs exhibit low water solubility, strong off-flavors/odors, and are generally unstable and easily degraded under common processing and storage conditions. Encapsulation is a technology that enables the delivery in food systems, the protection, as well as the controlled and targeted release of BACs. Scope and approach The …

Modularity as a source of new morphological variation in the mandible of hybrid mice.

2012

Abstract Background Hybridization is often seen as a process dampening phenotypic differences accumulated between diverging evolutionary units. For a complex trait comprising several relatively independent modules, hybridization may however simply generate new phenotypes, by combining into a new mosaic modules inherited from each parental groups and parts intermediate with respect to the parental groups. We tested this hypothesis by studying mandible size and shape in a set of first and second generation hybrids resulting from inbred wild-derived laboratory strains documenting two subspecies of house mice, Musmusculus domesticus and Musmusculus musculus. Phenotypic variation of the mandible…

Temperate Fish Detection and Classification: a Deep Learning based Approach

2021

A wide range of applications in marine ecology extensively uses underwater cameras. Still, to efficiently process the vast amount of data generated, we need to develop tools that can automatically detect and recognize species captured on film. Classifying fish species from videos and images in natural environments can be challenging because of noise and variation in illumination and the surrounding habitat. In this paper, we propose a two-step deep learning approach for the detection and classification of temperate fishes without pre-filtering. The first step is to detect each single fish in an image, independent of species and sex. For this purpose, we employ the You Only Look Once (YOLO) …

Comparative biogeography of echinoids, bivalves and gastropods from the Southern Ocean.

2013

ABSTRACTAim Biogeographical patterns within three classes, the Echinoidea, Bivalvia andGastropoda, were investigated in Antarctic, sub-Antarctic and cold-temperateareas based on species occurrence data. Faunal similarities among regions wereanalysed to: (1) test the robustness of the biogeographical patterns previouslyidentified in bivalves and gastropods; (2) compare them with the biogeographi-cal patterns identified for echinoids; and (3) evaluate the reliability of the bio-geographical provinces previously proposed, depending on the taxa andtaxonomic levels analysed.Location The Southern Ocean, sub-Antarctic islands and cold-temperate areassouth of 45° S latitude at depths of < 1000 m.Meth…