Effects of ice cover on the behavioural patterns of aquatic-mating male bearded seals

We used vocalizations to examine the behaviour of male bearded seals, Erignathus barbatus, in relation to ice cover over 2 consecutive years. Site fidelity varied between males. Territorial males returned to the same display locations in successive years, whereas roaming males returned to the study area but not to specific display locations. Males did not vocalize under the land-fast-ice edge and were therefore limited by access to areas of drift ice and open water for the purpose of displaying. Between-year fluctuations in ice cover restricted the number of displaying males during the early part of the mating season in April. Decreased ice cover during May resulted in more males displaying, but the number of males declined in June irrespective of the continued decline in ice cover. Roaming males were not heard when the ice cover was more than 60%, whereas territorial males were present during all ice conditions. Yearly fluctuations in ice cover may alter the long-term mating success of individuals and predictably available display areas may be preferred to areas that are more likely to be enclosed by fast-ice in some years.     

Small G proteins in peroxisome biogenesis: the potential involvement of ADP-ribosylation factor 6

Background  

Peroxisomes execute diverse and vital functions in virtually every eukaryote. New peroxisomes form by budding from pre-existing organelles or de novo by vesiculation of the ER. It has been suggested that ADP-ribosylation factors and COPI coatomer complexes are involved in these processes.     

From the Waters of the Empire to the Tanks of Paris: The Creation and Early Years of the Aquarium Tropical,Palais de la Porte Dorée

From May to November 1931, the Exposition coloniale internationale was held in Paris. Publicized as a trip around the world in a single day, it was designed to stimulate investments and general enthusiasm for the colonies. Along with exotic temporary pavilions representing the various colonies, model villages inhabited by colonial natives, and pavilions representing commercial product brands and other colonial powers, the exposition included a zoo and an aquarium featuring animals from the colonies. Installing a large aquarium had been a costly and difficult process, and construction was plagued by many delays and problems. But when the aquarium finally opened a few months into the exposition, it quickly became a favorite of the public. With the double mission to provide a living synthesis of the products of the warm waters of the French empire and give visitors a sense of the diversity, beauty, and economic resources of their colonial possessions, the aquarium functioned as a panorama that presented a striking visual metaphor for the empire. This article follows the aquarium during the exposition and in the years that followed. We explore its place in the history of aquaria in general and pay particular attention to its role in the exposition and within the French colonial context of the 1930s and onward. Here, both the scientists in charge of the site and the aquatic animals living in its tanks and terrariums provide a window into the relationship of marine biology, public education, consumerism, and colonialism at mid-twentieth century.     

Sleep deprivation sensitizes human craniofacial muscles

It is unknown whether and how sleep deprivation influences craniofacial muscle sensitivity in healthy humans. We investigated whether total sleep deprivation (TSD) and one night of recovery sleep (RS) can alter mechanical pain sensitivity in temporal and masseter muscles. Fifteen healthy volunteers participated in three consecutive sessions. Pressure pain thresholds were measured on the temporal and masseter muscles. Both temporal and masseter muscles became sensitized after 24?h of TSD. RS reversed the muscle sensitization.     

From leaf to label: A robust automated workflow for stomata detection

1. Plant leaf stomata are the gatekeepers of the atmosphere–plant interface and are essential building blocks of land surface models as they control transpiration and photosynthesis. Although more stomatal trait data are needed to significantly reduce the error in these model predictions, recording these traits is time‐consuming, and no standardized protocol is currently available. Some attempts were made to automate stomatal detection from photomicrographs; however, these approaches have the disadvantage of using classic image processing or targeting a narrow taxonomic entity which makes these technologies less robust and generalizable to other plant species. We propose an easy‐to‐use and adaptable workflow from leaf to label. A methodology for automatic stomata detection was developed using deep neural networks according to the state of the art and its applicability demonstrated across the phylogeny of the angiosperms.
2. We used a patch‐based approach for training/tuning three different deep learning architectures. For training, we used 431 micrographs taken from leaf prints made according to the nail polish method from herbarium specimens of 19 species. The best‐performing architecture was tested on 595 images of 16 additional species spread across the angiosperm phylogeny.
3. The nail polish method was successfully applied in 78% of the species sampled here. The VGG19 architecture slightly outperformed the basic shallow and deep architectures, with a confidence threshold equal to 0.7 resulting in an optimal trade‐off between precision and recall. Applying this threshold, the VGG19 architecture obtained an average F‐score of 0.87, 0.89, and 0.67 on the training, validation, and unseen test set, respectively. The average accuracy was very high (94%) for computed stomatal counts on unseen images of species used for training.
4. The leaf‐to‐label pipeline is an easy‐to‐use workflow for researchers of different areas of expertise interested in detecting stomata more efficiently. The described methodology was based on multiple species and well‐established methods so that it can serve as a reference for future work.

     

Cryptic diversity and ecosystem functioning: a complex tale of differential effects on decomposition

Oecologia - Marine ecosystems are experiencing accelerating population and species loss. Some ecosystem functions are decreasing and there is growing interest in the link between biodiversity and...