Physiology and functional biology of Rhizostomeae jellyfish.

Rhizostomeae species attract our attention because of their distinctive body shape, their large size and because of blooms of some species in coastal areas around the world. The impacts of these blooms on human activities, and the interest in consumable species and those of biotechnological value have led to a significant expansion of research into the physiology and functional biology of Rhizostomeae jellyfish over the last years. This review brings together information generated over these last decades on rhizostome body composition, locomotion, toxins, nutrition, respiration, growth, among other functional parameters.

A Bronze Age town in the Khaybar walled oasis: Debating early urbanization in Northwestern Arabia.

Recent exploration of the Khaybar oasis by the Khaybar Longue Durée Archaeological Project (AFALULA-RCU-CNRS) has led to the discovery of an exceptional Bronze Age fortified site called al-Natah. For the first time in Northwestern Arabia, the characteristics of a third/second-millennium-BCE settlement can be assessed over a large area. Preliminary archaeological survey and soundings have revealed a fortified 2.

Hydromechanical properties of metachronal swimming in polychaetes.

Free-swimming polychaetes are common in marine habitats and exhibit a unique form of swimming whereby a metachronal wave occurs simultaneously with a bending body wave. This body wave is unusual among swimming animals because it travels in the same direction as the animal's swimming direction. However, we currently lack a mechanistic understanding of this unusual form of locomotion.

The impact of print exposure on deaf student literacy.

Recent studies suggest that benefiting early from both a cochlear implant (CI) and exposure to cued speech (CS, support system for the perception of oral language) positively impacts deaf children's speech perception, speech intelligibility, and reading. This study aims to show how: 1/CS-based speech perception ("cue reading"), and speech intelligibility might also constitute precise measures for determining the impact of CI and CS on deaf students' literary performance; 2/print exposure might also be a predictive factor in this equation. We conducted regression analyses to examine the impact of these three variables in two experiments conducted on Grade 2-3 deaf children and Grade 6-9 deaf adolescents.

Flame Characterization of Cofiring Gaseous and Solid Fuels in Suspensions.

This work characterizes technical scale flames of suspension firing of gaseous and solid fuel mixtures through in-flame measurements with focus on nitrogen oxide (NO) formation. The aims are to investigate the impacts of substituting a solid fuel with a gaseous fuel on the important mechanisms for NO formation and to highlight important considerations for burner design. The investigation was performed in a 100 kW test unit that fires mixtures of propane and lignite.

Spinning and corkscrewing of oceanic macroplankton revealed through in situ imaging.

Helical motion is prevalent in nature and has been shown to confer stability and efficiency in microorganisms. However, the mechanics of helical locomotion in larger organisms (>1 centimeter) remain unknown. In the open ocean, we observed the chain forming salp, , swimming in helices.

Repeated co-option of HMG-box genes for sex determination in brown algae and animals.

In many eukaryotes, genetic sex determination is not governed by XX/XY or ZW/ZZ systems but by a specialized region on the poorly studied U (female) or V (male) sex chromosomes. Previous studies have hinted at the existence of a dominant male-sex factor on the V chromosome in brown algae, a group of multicellular eukaryotes distantly related to animals and plants. The nature of this factor has remained elusive.

Turning kinematics of the scyphomedusa.

Scyphomedusae are widespread in the oceans and their swimming has provided valuable insights into the hydrodynamics of animal propulsion. Most of this research has focused on symmetrical, linear swimming. However, in nature, medusae typically swim circuitous, nonlinear paths involving frequent turns.

Nectophore coordination and kinematics by physonect siphonophores.

Siphonophores are ubiquitous and often highly abundant members of pelagic ecosystems throughout the open ocean. They are unique among animal taxa in that many species use multiple jets for propulsion. Little is known about the kinematics of the individual jets produced by nectophores (the swimming bells of siphonophores) or whether the jets are coordinated during normal swimming behavior.

Ontogenetic transitions, biomechanical trade-offs and macroevolution of scyphozoan medusae swimming patterns.

Ephyrae, the early stages of scyphozoan jellyfish, possess a conserved morphology among species. However, ontogenetic transitions lead to morphologically different shapes among scyphozoan lineages, with important consequences for swimming biomechanics, bioenergetics and ecology. We used high-speed imaging to analyse biomechanical and kinematic variables of swimming in 17 species of Scyphozoa (1 Coronatae, 8 "Semaeostomeae" and 8 Rhizostomeae) at different developmental stages.

Diverse eukaryotic phytoplankton from around the Marquesas Islands documented by combined microscopy and molecular techniques.

Oceanic phytoplankton serve as a base for the food webs within the largest planetary ecosystem. Despite this, surprisingly little is known about species composition, function and ecology of phytoplankton communities, especially for vast areas of the open ocean. In this study we focus on the marine phytoplankton microflora from the vicinity of the Marquesas Islands in the Southern Pacific Ocean collected during the Tara Oceans expedition.

A fundamental propulsive mechanism employed by swimmers and flyers throughout the animal kingdom.

Even casual observations of a crow in flight or a shark swimming demonstrate that animal propulsive structures bend in patterned sequences during movement. Detailed engineering studies using controlled models in combination with analysis of flows left in the wakes of moving animals or objects have largely confirmed that flexibility can confer speed and efficiency advantages. These studies have generally focused on the material properties of propulsive structures (propulsors).

The baseless mutant links protein phosphatase 2A with basal cell identity in the brown alga Ectocarpus.

The first mitotic division of the initial cell is a key event in all multicellular organisms and is associated with the establishment of major developmental axes and cell fates. The brown alga Ectocarpus has a haploid-diploid life cycle that involves the development of two multicellular generations: the sporophyte and the gametophyte. Each generation deploys a distinct developmental programme autonomously from an initial cell, the first cell division of which sets up the future body pattern.

Quantifying the feeding behavior and trophic impact of a widespread oceanic ctenophore.

Oceanic ctenophores are widespread predators on pelagic zooplankton. While data on coastal ctenophores often show strong top-down predatory impacts in their ecosystems, differing morphologies, prey capture mechanisms and behaviors of oceanic species preclude the use of coastal data to draw conclusion on oceanic species. We used high-resolution imaging methods both in situ and in the laboratory to quantify interactions of Ocyropsis spp.

Cooperative hydrodynamics accompany multicellular-like colonial organization in the unicellular ciliate .

Evolution of multicellularity from early unicellular ancestors is arguably one of the most important transitions since the origin of life. Multicellularity is often associated with higher nutrient uptake, better defense against predation, cell specialization and better division of labor. While many single-celled organisms exhibit both solitary and colonial existence, the organizing principles governing the transition and the benefits endowed are less clear.

A primary small cell neuroendocrine carcinoma (SCNC) of the oral cavity (cheek mucosa): Description of a case report.

Background: Small cell neuroendocrine carcinoma (SCNC) of the oral cavity is a poorly differentiated, high-grade and very aggressive tumor with a poor prognosis.

Case Description: A 64-year-old, Caucasian, smoker man consulted for an ulcero-necrotic, exophytic, lesion of the right retromolar trigone. Haed&neck CT scan showed a right tonsillar tumor lesion.

Distributed propulsion enables fast and efficient swimming modes in physonect siphonophores.

Many fishes employ distinct swimming modes for routine swimming and predator escape. These steady and escape swimming modes are characterized by dramatically differing body kinematics that lead to context-adaptive differences in swimming performance. Physonect siphonophores, such as , are colonial cnidarians that produce multiple jets for propulsion using swimming subunits called nectophores.

A fatal primary gastric melanoma treated by a double immunotherapy with ipilimumab/nivolumab: description of a case report.

Background: Primary gastric melanoma (GM) is a very uncommon tumor with a poor prognosis. Until now, only a few cases have been reported in the literature.

Case Description: A 70-year-old, Caucasian, ex-smoker man, presented with asthenia, anorexia, and weight loss of 5 kg during the last 2 months.

Review of Optical Thermometry Techniques for Flows at the Microscale towards Their Applicability to Gas Microflows.

Thermometry techniques have been widely developed during the last decades to analyze thermal properties of various fluid flows. Following the increasing interest for microfluidic applications, most of these techniques have been adapted to the microscale and some new experimental approaches have emerged. In the last years, the need for a detailed experimental analysis of gaseous microflows has drastically grown due to a variety of exciting new applications.

The influence of Latino cultural values on the perceived caregiver role of family members with Alzheimer's disease and related dementias.

Objectives: We explored how Latino cultural values play a role in perceived caregiving experiences.

Design: We conducted a qualitative study that used individual, in-depth, semi-structured interviews with middle-aged and older Latinos who were primary caregivers of family members with Alzheimer's disease and related dementias (ADRD). The interview guide consisted of questions about participants' perceptions of family caregiving and interrelationships between the caregiver and care recipient.

Pollinators of the sea: A discovery of animal-mediated fertilization in seaweed.

The long-held belief that animal-mediated pollination is absent in the sea has recently been contradicted in seagrasses, motivating investigations of other marine phyla. This is particularly relevant in red algae, in which female gametes are not liberated and male gametes are not flagellated. Using experiments with the isopod and the red alga , we demonstrate that biotic interactions dramatically increase the fertilization success of the alga through animal transport of spermatia on their body.

Assessing real-world vaccine effectiveness against severe forms of SARS-CoV-2 infection: an observational study from routine surveillance data in Switzerland.

Background: In Switzerland, SARS-CoV-2 vaccination campaigns started in early 2021. Vaccine coverage reached 65% of the population in December 2021, mostly with mRNA vaccines from Moderna and Pfizer-BioNtech. Simultaneously, the proportion of vaccinated among COVID-19-related hospitalisations and deaths rose, creating some confusion in the general population.

Quantum relaxation in a system of harmonic oscillators with time-dependent coupling.

In the context of the de Broglie-Bohm pilot-wave theory, numerical simulations for simple systems have shown that states that are initially out of quantum equilibrium-thus violating the Born rule-usually relax over time to the expected || distribution on a coarse-grained level. We analyse the relaxation of non-equilibrium initial distributions for a system of coupled one-dimensional harmonic oscillators in which the coupling depends explicitly on time through numerical simulations, focusing on the influence of different parameters such as the number of modes, the coarse-graining length and the coupling constant. We show that in general the system studied here tends to equilibrium, but the relaxation can be retarded depending on the values of the parameters, particularly to the one related to the strength of the interaction.

A robust approach to estimate relative phytoplankton cell abundances from metagenomes.

Phytoplankton account for >45% of global primary production, and have an enormous impact on aquatic food webs and on the entire Earth System. Their members are found among prokaryotes (cyanobacteria) and multiple eukaryotic lineages containing chloroplasts. Genetic surveys of phytoplankton communities generally consist of PCR amplification of bacterial (16S), nuclear (18S) and/or chloroplastic (16S) rRNA marker genes from DNA extracted from environmental samples.

Swimming kinematics and performance of spinal transected lampreys with different levels of axon regeneration.

Axon regeneration is critical for restoring neural function after spinal cord injury. This has prompted a series of studies on the neural and functional recovery of lampreys after spinal cord transection. Despite this, there are still many basic questions remaining about how much functional recovery depends on axon regeneration.