Search results for "SITE"
showing 10 items of 8388 documents
Divergent parasite infections in sympatric cichlid species in Lake Victoria
2018
Parasitism has been proposed as a factor in host speciation, as an agent affecting coexistence of host species in species‐rich communities and as a driver of post‐speciation diversification. Young adaptive radiations of closely related host species of varying ecological and genomic differentiation provide interesting opportunities to explore interactions between patterns of parasitism, divergence and coexistence of sympatric host species. Here, we explored patterns in ectoparasitism in a community of 16 fully sympatric cichlid species at Makobe Island in Lake Victoria, a model system of vertebrate adaptive radiation. We asked whether host niche, host abundance or host genetic differentiatio…
Experimental approaches to study the transmission and infection of Cardiocephaloides longicollis (Rudolphi, 1819) Dubois, 1982 (Trematoda, Strigeidae…
2023
Los trematodos (Platyhelminthes, Trematoda) son componentes ubicuos de los ecosistemas y, en las últimas décadas, los investigadores han mostrado un interés creciente en ellos, especialmente en sus estrategias y mecanismos de transmisión e infección. Los digeneos forman un grupo grande y generalmente tienen un ciclo de vida complejo con tres huéspedes. El primer huésped intermedio suele ser un molusco, el segundo huésped intermedio puede ser un huésped invertebrado o vertebrado, y el huésped definitivo suele ser un vertebrado. En el huésped definitivo, el parásito se convierte en adulto y se reproduce sexualmente. Luego, los huevos del parásito se liberan en el medio ambiente donde el mirac…
Establishment and interspecific associations in two species of Ichthyocotylurus (Trematoda) parasites in perch (Perca fluviatilis)
2011
Background: Co-infections of multiple parasite species in hosts may lead to interspecific associations and subsequently shape the structure of a parasite community. However, few studies have focused on these associations in highly abundant parasite species or, in particular, investigated how the associations develop with time in hosts exposed to co-infecting parasite species for the first time. We investigated metacercarial establishment and interspecific associations in the trematodes Ichthyocotylurus variegatus and I. pileatus co-infecting three age cohorts of young perch (Perca fluviatilis). Results: We found that the timing of transmission of the two Ichthyocotylurus species was very si…
“Face the cow”: reconnecting to nature and increasing capacities for pro-environmental agency
2020
Arts-based practices can support sustainability, combined with research that points out needs for intervention. We practiced environmental sensitivity and dialogic art with fifth-grade school pupils as part of an International Socially Engaged Art Symposium (ISEAS2019). Using arts-based action research methodology, our case study focused on the opportunities of arts-based environmental education in advancing the management of meadows and wood-pastures. We explored nature connectedness and pro-environmental mindsets and behaviors among the pupils and artists/researchers. The artistic results encompassed the dialogic interactions of the intervention, exhibited artworks, and audiovisual docume…
Physical-chemical properties and possible applications of clay minerals and humic acid composite materials
2019
Article Pollution caused by pharmaceuticals has become an increasingly serious issue, therefore innovative and cost – effective methods of pharmaceutical’s removal must be studied. Clay – humic acid composite materials can be considered as prospective and low cost sorbents for contaminants. The aim of this study is to develop clay mineral and humic acid composite materials and to characterise their possible applications. For this research, three types of clay minerals (montmorillonite, kaolinite and bentonite) were modified with three types of humic substances: technical humic acid from lignite, humic substances extracted from raised bog peat and technical K humate from lignite. The sorptio…
CoS2/TiO2 Nanocomposites for Hydrogen Production under UV Irradiation
2019
Transition metal chalcogenides have intensively focused on photocatalytic hydrogen production for a decade due to their stronger edge and the quantum confinement effect. This work mainly focuses on synthesis and hydrogen production efficiencies of cobalt disulfide (CoS2)-embedded TiO2 nanocomposites. Materials are synthesized by using a hydrothermal approach and the hydrogen production efficiencies of pristine CoS2, TiO2 nanoparticles and CoS2/TiO2 nanocomposites are compared under UV irradiation. A higher amount of hydrogen production (2.55 mmol g&minus
Recurrent domestication by Lepidoptera of genes from their parasites mediated by Bracoviruses
2015
Bracoviruses are symbiotic viruses associated with tens of thousands of species of parasitic wasps that develop within the body of lepidopteran hosts and that collectively parasitize caterpillars of virtually every lepidopteran species. Viral particles are produced in the wasp ovaries and injected into host larvae with the wasp eggs. Once in the host body, the viral DNA circles enclosed in the particles integrate into lepidopteran host cell DNA. Here we show that bracovirus DNA sequences have been inserted repeatedly into lepidopteran genomes, indicating this viral DNA can also enter germline cells. The original mode of Horizontal Gene Transfer (HGT) unveiled here is based on the integrativ…
Commissioned Book Review : Aliaksei Kazharski, Eurasian Integration and the Russian World: Regionalism as an Identitary Enterprise
2019
Ideologian jäljillä : perusopetuksen opetussuunnitelman perusteiden arvoperustan poliittinen analyysi
2016
Perusopetuksen opetussuunnitelman perusteet on lainsäädännön ohella merkittävin asiakirja, jolla perusopetuksen toimintaa ohjataan ja määritellään Suomessa. Tässä tutkimuksessa tarkastelen POPS2014-opetussuunnitelmaa poliittisena dokumenttina, joka on syntynyt eri intressiryhmien valtataistelun tuloksena. Tutkimuksen tarkoituksena on selvittää, millaisia ideologisia piirteitä opetussuunnitelman arvoperustaan on artikuloitu ja millaisilla artikulaatioilla hegemoniaa pyritään rakentamaan. Tutkimus perustuu laclaulaiseen diskurssiteoriaan, joka on jälkifoundationalistinen viitekehys ja ongelmalähtöinen metodi. Tässä tutkimuksessa lähestymistapa mahdollistaa neutraaleilta ja luonnollisilta näyt…
Ikääntymisen merkitys työelämässä – näkökulmia ikäjohtamisen tutkimukseen
2020
Implications of ageing for work: Perspectives for research The article, which focuses on age management and its various definitions and interpretations, was prompted by the need to examine the significance of age management within an organisational framework. The research material combines conceptual research and relevant literature. The National Programme on Ageing Workers 1998–2002 serves as the background for the study. In addition to providing essential data, the Programme was the first to introduce the concept of age management. Since its introduction, age management has been given a wide variety of meanings. Therefore it proved necessary to take a closer look at the relationship betwe…