Search results for "Groups"
showing 10 items of 1120 documents
Egalitarian mixed-species bird groups enhance winter survival of subordinate group members but only in high-quality forests
2020
AbstractOnly dominant individuals have unrestricted access to contested resources in group-living animals. In birds, subordinates with restricted access to resources may respond to intragroup contests by acquiring extra body reserves to avoid periods of food shortage. In turn, higher body mass reduces agility and increases predation and mortality risk to subordinates. Birds often live in hierarchically organized mixed-species groups, in which heterospecific individuals are considered to substitute for conspecifics as protection against predators at a significantly reduced competition cost. Crested tits (Lophophanes cristatus) and willow tits (Poecile montanus) form mixed-species groups duri…
Genetic and morphometric variations of Mediterranean hake,Merluccius merluccius,in the Strait of Sicily (central Mediterranean): Implications for sto…
2004
Allozyme, morphometric and growth analyses were applied to samples collected in the Strait of Sicily (central Mediterranean Sea) to test the hypothesis of the existence of a unique hake stock (Merluccius merluccius) in the study area. The level of genetic variation was detected from five polymorphic loci (ADH*, PGI-1; PGI-2*, PGM', SOD-1*). The average observed heterozygosity amounted to 0.421, while the average expected was 0.353. Weir & Cockerham statistics showed no heterogeneity, except for the single PGP locus (9 = 0.011; P 0.05). Morphometric analyses revealed some differentiation. Females showed different relationships in six out of eight morphometric indices with total length, while…
Mixed company : a framework for understanding the composition and organization of mixed‐species animal groups
2020
Mixed‐species animal groups (MSGs) are widely acknowledged to increase predator avoidance and foraging efficiency, among other benefits, and thereby increase participants' fitness. Diversity in MSG composition ranges from two to 70 species of very similar or completely different phenotypes. Yet consistency in organization is also observable in that one or a few species usually have disproportionate importance for MSG formation and/or maintenance. We propose a two‐dimensional framework for understanding this diversity and consistency, concentrating on the types of interactions possible between two individuals, usually of different species. One axis represents the similarity of benefit types …
Bachelor groups form due to individual choices or environmental disrupters in African striped mice
2021
International audience; In several mammal species, bachelor groups occur as a regular life history stage between dispersal and becoming the breeding male of a multi-female group. However, it is rarely investigated how such groups come into existence and how males that choose this strategy differ in life history traits from other males. Males of the socially flexible African striped mouse Rhabdomys pumilio have been historically reported to adopt one of three alternative tactics, i.e., small group-living philopatric males, intermediate solitary living roaming males, or large group-living territorial males. Here, we describe for the first time, bachelors as a fourth male tactic. Using long-te…
Periodic Controls in Step 2 Strictly Convex Sub-Finsler Problems
2020
We consider control-linear left-invariant time-optimal problems on step 2 Carnot groups with a strictly convex set of control parameters (in particular, sub-Finsler problems). We describe all Casimirs linear in momenta on the dual of the Lie algebra. In the case of rank 3 Lie groups we describe the symplectic foliation on the dual of the Lie algebra. On this basis we show that extremal controls are either constant or periodic. Some related results for other Carnot groups are presented. peerReviewed
Exposure to a Highly Caloric Palatable Diet During Pregestational and Gestational Periods Affects Hypothalamic and Hippocampal Endocannabinoid Levels…
2016
Journal Article; Exposure to unbalanced diets during pre-gestational and gestational periods may result in long-term alterations in metabolism and behavior. The contribution of the endocannabinoid system to these long-term adaptive responses is unknown. In the present study, we investigated the impact of female rat exposure to a hypercaloric-hypoproteic palatable diet during pre-gestational, gestational and lactational periods on the development of male offspring. In addition, the hypothalamic and hippocampal endocannabinoid contents at birth and the behavioral performance in adulthood were investigated. Exposure to a palatable diet resulted in low weight offspring who exhibited low hypotha…
The molecular epidemiology of HIV-1 in the Comunidad Valenciana (Spain): analysis of transmission clusters
2017
AbstractHIV infections are still a very serious concern for public heath worldwide. We have applied molecular evolution methods to study the HIV-1 epidemics in the Comunidad Valenciana (CV, Spain) from a public health surveillance perspective. For this, we analysed 1804 HIV-1 sequences comprising protease and reverse transcriptase (PR/RT) coding regions, sampled between 2004 and 2014. These sequences were subtyped and subjected to phylogenetic analyses in order to detect transmission clusters. In addition, univariate and multinomial comparisons were performed to detect epidemiological differences between HIV-1 subtypes, and risk groups. The HIV epidemic in the CV is dominated by subtype B i…
Cardiolipin synthesis in brown and beige fat mitochondria is essential for systemic energy homeostasis
2018
Summary Activation of energy expenditure in thermogenic fat is a promising strategy to improve metabolic health, yet the dynamic processes that evoke this response are poorly understood. Here we show that synthesis of the mitochondrial phospholipid cardiolipin is indispensable for stimulating and sustaining thermogenic fat function. Cardiolipin biosynthesis is robustly induced in brown and beige adipose upon cold exposure. Mimicking this response through overexpression of cardiolipin synthase (Crls1) enhances energy consumption in mouse and human adipocytes. Crls1 deficiency in thermogenic adipocytes diminishes inducible mitochondrial uncoupling and elicits a nuclear transcriptional respons…
Spanish Cell Therapy Network (TerCel): 15 years of successful collaborative translational research
2019
On behalf of TerCel
Does Embryo Culture Medium Influence the Health and Development of Children Born after In Vitro Fertilization?
2016
International audience; In animal studies, extensive data revealed the influence of culture medium on embryonic development, foetal growth and the behaviour of offspring. However, this impact has never been investigated in humans. For the first time, we investigated in depth the effects of embryo culture media on health, growth and development of infants conceived by In Vitro Fertilization until the age of 5 years old. This single-centre cohort study was based on an earlier randomized study. During six months, in vitro fertilization attempts (No. 371) were randomized according to two media (Single Step Medium—SSM group) or Global medium (Global group). This randomized study was stopped prem…