Search results for "Host"
showing 10 items of 1982 documents
Nonlinear resonances and some of their applications to information processing
2021
The study of resonance phenomena in nonlinear dynamical systems has drawn considerable attention for years. The most studied nonlinear resonance is undoubtedly the famous stochastic resonance, which consists of perturbing a nonlinear system with an appropriate amount of noise to enhance the detection of a subthreshold input signal. Since the introduction of stochastic resonance in the context of climate dynamics, it was later observed that a deterministic high frequency perturbation can replace noise leading to vibrational resonance. Even if this latter resonance was investigated in many areas of science for more than two decades now, it is still receiving attentions. It is the subject of t…
Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) differ in their suitability as hosts for the endangered freshwater pearl mussel (Margari…
2017
1. European populations of the freshwater pearl mussel (FPM, Margaritifera margaritifera) have widely collapsed, and despite many types of conservation actions the number of successful restoration trials has remained limited. The goal of this study was to find new aspects for the conservation by investigating whether there are population-specific differences in suitability of Atlantic salmon (Salmo salar) and brown trout (S. trutta) as the hosts for the parasitic glochidium larvae of FPM, depending probably on the historical occurrence of these salmonid species in FPM habitats. 2. We studied the potential host specificity both in the field and in laboratory by exposing salmonid fish to FPM …
The occurrence of Echinorhynchus salmonis Müller, 1784 in benthic amphipods in the Baltic Sea
2015
Abstract: The acanthocephalan Echinorhynchus salmonis Müller, 1784 is a common parasite of salmonid fish, but it has rarely been reported from an intermediate host. Samples of benthic amphipods, Monoporeia affinis (Lindström), were taken from multiple, deep sites (usually below 70 m) in the Gulf of Bothnia over the course of more than a decade and examined for acanthocephalans. Overall, only 0.44% of 23 296 amphipods were infected, all with just a single worm. This prevalence is consistent with several previous reports of acanthocephalans in deep-water, benthic amphipods, but it appears low compared to that often reported for acanthocephalan species infecting littoral amphipods. Parasite oc…
Exploring the phenomenon of host confirmity pressure : immigrants' experiences of host conformity pressure in Finland in relation to their acculturat…
2012
The present study investigates the phenomenon of host conformity pressure and its possible consequences on acculturation from immigrants’ perspective. The research is motivated by the discrepancies between results of previous studies on the topic, the relatively small amount of research about immigration in Finland, and the will to examine adaptation issues from an intercultural communication perspective. The study uses different adaptation theories, notably Berry’s (1997) model of acculturative strategies. It also builds on Kim’s (2001) definition of host conformity pressure and Emerson’s (1968) theory of structural power. This research aims at examining (1) what immigrants identify as hos…
Multidimensionality and intra-individual variation in host manipulation by an acanthocephalan
2008
Parasitology, 135 (5)
Sinemurian to lowermost Toarcian ammonites of the Brescian Prealps (Southern Alps, Italy): preliminary biostratigraphical framework and correlations.
2009
10 pages; International audience; A set of 28 ammonite biohorizons or faunal assemblages is proposed for the Sinemurian, the Pliensbachian and the lowermost Toarcian of the Brescian Prealps, in part based on the published data of the authors of this contribution and partly on new results, derived both from recent field investigations and from the study of the historical collection of Lower Jurassic ammonites preserved in the Museum of Natural Sciences of Brescia (Northern Italy). The biohorizons are present in the Liassic carbonate succession of the Brescian Prealps, cropping out between the eastern surroundings of Brescia (Botticino), to the east, and Lake Iseo, to the west. Since the Hett…
Defining gut mycobiota for wild animals: a need for caution in assigning authentic resident fungal taxa
2021
Animal gut mycobiota, the community of fungi that reside within the gastrointestinal tract, make an important contribution to host health. Accordingly, there is an emerging interest to quantify the gut mycobiota of wild animals. However, many studies of wild animal gut mycobiota do not distinguish between the fungi that likely can reside within animal gastrointestinal tracts from the fungal taxa that are non-residents, such as macrofungi, lichens or plant symbionts/pathogens that can be ingested as part of the host’s diet. Confounding the non-resident and resident gut fungi may obscure attempts to identify processes associated with the authentic, resident gut mycobiota per se. To redress th…
Coordination Chemistry of a Bis(Tetrazine) Tweezer: A Case of Host-Guest Behavior with Silver Salts
2021
The carbon-carbon cross-coupling of phenyl s-tetrazine (Tz) units at their ortho-phenyl positions allows the formation of constrained bis(tetrazines) with original tweezer structures. In these compounds, the face-to-face positioning of the central tetrazine cores is reinforced by π-stacking of the electron-poor nitrogen-containing heteroaromatic moieties. The resulting tetra-aromatic structure can be used as a weak coordinating ligand with cationic silver. This coordination generates a set of bis(tetrazine)-silver(I) coordination complexes tolerating a large variety of counter anions of various geometries, namely, PF6−, BF4−, SbF6−, ClO4−, NTf2−, and OTf−. These compounds were characterized…
Long-lasting effect of stress on susceptibility of a freshwater clam to copepod parasitism.
2005
The question whether a stress event can have a long-lasting effect on susceptibility to parasites was studied using a freshwater bivalve clam and its crustacean parasite as a model system. Anodonta piscinalis clams were collected from 2 populations during August–September 2002. Clams were transported to the laboratory and marked. The stressed clams were subjected to low oxygen for 25 days, while the unstressed control clams were caged in their lakes of origin for the same period. Then the clams were transported to a third lake where they were exposed to natural infections by the ergasilid copepod, Paraergasilus rylovi , 11 months after the stress event. The stressed clams were more intensiv…
Influence of trematode parasitism on the growth of a bivalve host in the field.
1998
Abstract Trematode-induced gigantism of molluscs, enhanced growth of trematode-parasitised individuals, has been observed in many laboratory studies. This study reports the effect of the sterilising trematode, Rhipidicotyle fennica , on the growth of the freshwater clam Anodonta piscinalis under field conditions. In addition to single infections (prevalence 44%), a few clams (3%) were infected with both R. fennica and Rhipidocotyle campanula . Parasite-induced gigantism was not found; parasites lowered host growth. The decrease in growth was correlated with the quantity of parasite material. Clams with double infections grew the least, although they did not differ significantly from hosts w…