Search results for "Lions"
showing 10 items of 22 documents
A new species of Ascocotyle (Trematoda: Heterophyidae) from the South American sea lion, Otaria flavescens, off Patagonia, Argentina.
2012
We describe a new heterophyid species, Ascocotyle (Ascocotyle) patagoniensis n. sp., based on specimens collected from the intestines of the South American sea lion Otaria flavescens from Patagonia (Argentina). Ascocotyle (A.) patagoniensis n. sp. is distinguished from the other species of the subgenus by the number of circumoral spines, which are arranged in 2 rows of 18 to 23. The new species also differs from the other species in having a gonotyl without papillae. The specimens exhibited the widest seminal receptacle described for a species of this subgenus. Species of the subgenus Ascocotyle usually infect fish-eating birds or mammals in freshwater or brackish habitats. Ascocotyle (A.) …
Intestinal helminth fauna of the South American sea lion Otaria flavescens and fur seal Arctocephalus australis from northern Patagonia, Argentina
2012
AbstractWe report on the intestinal helminth fauna of 56 South American sea lions, Otaria flavescens, and 5 South American fur seals, Arctocephalus australis, from northern Patagonia, Argentina. A total of 97,325 helminth specimens were collected from sea lions. Gravid individuals were represented by 6 species of parasites: 1 digenean (Ascocotyle (Ascocotyle) patagoniensis), 1 cestode (Diphyllobothrium spp.), 3 nematodes (Uncinaria hamiltoni, Contracaecum ogmorhini s.s., Pseudoterranova cattani) and 1 acanthocephalan (Corynosoma australe). In addition, third-stage larvae of 2 nematodes (Contracaecum sp. and Anisakis sp. type I) and 3 juvenile acanthocephalans (Andracantha sp., Profilicollis…
Life begins when the sea lion is ashore: microhabitat use by a louse living on a diving mammal host
2012
AbstractAmong Anoplura, the family Echinophthiriidae includes species that infest pinnipeds and otters. Previous evidence obtained from pinnipeds infested by echinophthiriids, specifically from seals, indicates that flippers are the preferred infestation sites, while lice from fur seals select areas in the pelage. We studied habitat selection of Antarctophthirus microchir on South American sea lion pups (Otaria flavescens Shaw, 1800) from Patagonia, Argentina, during the austral summer of 2009. We found a clear pattern of habitat selection: eggs are laid on the dorsal surface; nymphs 1 hatch there and then migrate to the belly, where they develop into adults and copulate; and then ovigerous…
Population dynamics of Antarctophthirus microchir (Anoplura: Echinophthiriidae) in pups from South American sea lion, Otaria flavescens, in Northern …
2009
We analysed population dynamics of the louse Antarctophthirus microchir in pups of the South American sea lion, Otaria flavescens, at the Punta León rookery (Argentina) over a period of 2 years. A total of 136 pups were aged and marked at the beginning of the lactation period ashore, then sampled for lice at different times within 30 days. Sampling was restricted to the chest and belly, two sites where lice were especially abundant. This concentration on ventral areas might protect lice from thermal stress in the austral summer. Infestation patterns in pups ≤3 days old suggested that the potential for transmission increased from first nymphs to adults. Population trends of each instar with …
Scanning electron microscopy of Antarctophthirus microchir (Phthiraptera: Anoplura: Echinophthiriidae): Studying morphological adaptations to aquatic…
2012
The members of the Family Echinophthiriidae (Phthiraptera: Anoplura) are unique among insects because they infest hosts with an amphibious lifestyle. During their evolution they developed morphological traits that are reflected in unique features. The SEM is a helpful tool to analyze them. Knowing in detail the external structure of these lice is the first step to understand the whole process that derived from the co-adaptation of lice and pinnipeds to the marine environment. For the first time, we studied the external structure of all stages of an echinophthiriid louse. The results are discussed in the light of their evolutionary, functional, and ecological implications. Fil: Leonardi, Mar…
Nonlinear scalar field equations with general nonlinearity
2018
Consider the nonlinear scalar field equation \begin{equation} \label{a1} -\Delta{u}= f(u)\quad\text{in}~\mathbb{R}^N,\qquad u\in H^1(\mathbb{R}^N), \end{equation} where $N\geq3$ and $f$ satisfies the general Berestycki-Lions conditions. We are interested in the existence of positive ground states, of nonradial solutions and in the multiplicity of radial and nonradial solutions. Very recently Mederski [30] made a major advance in that direction through the development, in an abstract setting, of a new critical point theory for constrained functionals. In this paper we propose an alternative, more elementary approach, which permits to recover Mederski's results on the scalar field equation. T…
Dipole picture and the nonrelativistic expansion
2022
We study exclusive quarkonium production in the dipole picture at next-to-leading order (NLO) accuracy, using the non-relativistic expansion for the quarkonium wavefunction. This process offers one of the best ways to obtain information about gluon distributions at small $x$, in ultraperipheral heavy ion collisions and in deep inelastic scattering. The quarkonium light cone wave functions needed in the dipole picture have typically been available only at tree level, either in phenomenological models or in the nonrelativistic limit. In this paper, we discuss the compatibility of the dipole approach and the non-relativistic expansion and compute NLO relativistic corrections to the quarkonium …
Patterns of trunk spine growth in two congeneric species of acanthocephalan: investment in attachment may differ between sexes and species.
2012
SUMMARYAcanthocephalans have evolved a hooked proboscis and some taxa have trunk spines to attach to their definitive hosts. These structures are generated before being used, thus a key question is how investment in attachment could optimally be allocated through the ontogeny. The number and arrangement of hooks and spines are never modified in the definitive host, but it is unclear whether these structures grow during adult development. A comparison of the size of trunk spines between cystacanths and adults of Corynosoma cetaceum and C. australe indicated that spines grow in both species, but only in females, which also had significantly larger spines than males. This sexual dimorphism did…
Współpraca i partnerstwo : teoretyczne modele relacji organizacji pozarządowych z jednostkami administracji publicznej
2018
Theoretical nmdels were constructed to present and analyse relationships between public administration and non-governrnenlal organizations, cven ifthey difter in terins of central categories, usually point to the symmelry of the posiLion of the parties as the basis for the ąuality of relations between tliem. 'Ihe suggested form is partner ship; that is, co-operation where actors are cqual and as such, despite differences in resóurccs and compclences, tltey share fairly rights-, obligations and responsibility in the process of creating and implemenling social policies. This cąuality is the conscąuence of inereasing the capacity of non governmental organizations to participatc in this field, …
The Development of Teachers' and Their Students' Social and Emotional Learning During the “Learning to Be Project”-Training Course in Five European C…
2021
This study was funded by a project Learning to Be: Development of Practices and Methodologies for Assessing Social, Emotional and Health Skills within Education Systems (#4120034) in the framework of Erasmus+ KA3 program (582955-EPP-1-2016-2-LT-EPPKA3-PI-POLICY). We are also grateful for funding by the Academy of Finland (#308352) and Finnish Strategic Research Council (#327242).