Search results for "Ceph"
showing 10 items of 2036 documents
Variation and covariation in infectivity, virulence and immunodepression in the host-parasite association Gammarus pulex-Pomphorhynchus laevis.
2009
Parasites often manipulate host immunity for their own benefit, either by exacerbating or suppressing the immune response and this may directly affect the expression of parasite virulence. However, genetic variation in immunodepression, which is a prerequisite to its evolution, and the relationship between immunodepression and virulence, have rarely been studied. Here, we investigated the variation among sibships of the acanthocephalan parasite, Pomphorhynchus laevis , in infecting and in immunodepressing its amphipod host, Gammarus pulex . We also assessed the covariation between infectivity, parasite-induced immune depression and host mortality (parasite virulence). We found that infecti…
Dietary characterization of Savi s Warbler Locustaella luscinioides and Great Reed Warbler Acrocephalus rundinaceus in eastern Spain
2017
[EN] This research deals with two insectivorous reedbed-nesting songbirds, the Savi's Warbler Locustella luscinioides and the Great Reed Warbler Acrocephalus arundinaceus breeding at the Marjal de Pego-Oliva (Valencia-Alicante, Spain). Our aims were to study the diet and the prey selection of the two species and to assess the dietary differences between them. Diet composition has been assessed by examining samples off regurgitated food obtained using apomorphine as an emetic. Prey availability was estimated through standardized invertebrate sampling. The diet of the two warblers were significantly different and included arthropods belonging to the orders Araneida, Coleoptera, Hymenoptera, H…
Differential influence of Pomphorhynchus laevis (Acanthocephala) on the behaviour of native and invader gammarid species
2000
Although various species of acanthocephalan parasites can increase the vulnerability of their amphipod intermediate hosts to predation, particularly by altering their photophobic behaviour, their influence on the structure of amphipod communities and the success of invader species has so far received little attention. We compared the prevalence and behavioural influence of a fish acanthocephalan parasite, Pomphorhynchus laevis, in two species of amphipods, Gammarus pulex and Gammarus roeseli in sympatry in the river Ouche (Burgundy, eastern France). There, G. pulex is a resident species, whereas G. roeseli is a recent coloniser. Both uninfected G. pulex and G. roeseli were strongly photopho…
Bird and amphipod parasites illustrate a gradient from adaptation to exaptation in complex life cycle.
2010
6 pages; International audience; Trophically transmitted parasites modify the phenotype of their hosts, sometimes in a way that facilitates transmission. Parasite-induced changes can be either part of a manipulative strategy evolved to improve the transmission success of the parasite, or simply by-products of infection with no health effect. In the former case, manipulation is regarded as a parasite adaptation driven by the probability of being eaten by a suitable next host. Here, we consider the fact that manipulation may also be an 'exaptation': a trait that evolved for a certain use, but which has been co-opted for a new use. According to this view, features built by natural selection fo…
Factors Shaping Breeding Phenology in Birds: An Assessment of Two Sympatric Acrocephalus Warblers with Different Life Histories
2020
El periodo reproductivo es un rasgo crucial de la historia de la vida e implica importantes consecuencias para la eficacia biologica. Las diferencias en las estrategias de historia de vida pueden conducir a diferentes respuestas a las mismas condiciones ambientales, incluso entre especies estrechamente relacionadas. Investigar los factores que afectan el periodo reproductivo en especies estrechamente relacionadas y simpatricas puede ayudar a comprender la relacion entre los diferentes rasgos de la historia de vida y las respuestas especificas de las especies a los factores ecologicos. En este trabajo investigamos los efectos del momento estacional (fotoperiodo), la variabilidad climatica lo…
DNA barcoding of marine fishes from Saudi Arabian waters of the Gulf
2019
We used the cytochrome oxidase subunit I (coI) gene DNA to barcode 117 endemic Gulf and cosmopolitan Indo-West Pacific fish species belonging to 54 families and 13 orders. Novel DNA barcodes were provided for 18 fish species (Trachinocephalus sp., Nematalosa sp., Herklotsichthys lossei, Upeneus doriae, Trachurus indicus, Apogonichthyoides taeniatus, Verulux cypselurus, Favonigobius sp., Suezichthus gracilis, Sillago sp., Brachirus orientalis, Pegusa sp., Lepidotrigla bispinosa, Lepidotrigla sp., Grammoplites suppositus, Hippichthys sp., Paramonacanthus sp. and Triacanthus sp.). The species delimitation analysis, conducted with Poisson tree processes- Bayesian PTP (PTP-bPTP) and nucleotide-d…
Effect of Multiple Parasitic Infections on the Tolerance to Pollutant Contamination
2012
8 pages; International audience; The horizontally-transmitted acanthocephalan parasite Polymorphus minutus and the vertically-transmitted microsporidian parasite Dictyocoela roeselum have both been shown to influence on the antitoxic responses of mono-infected Gammarus roeseli exposed to cadmium. The present study investigates the effect of this co-infection on the antitoxic defence responses of naturally infected females exposed to cadmium stress. Our results revealed that, depending on the cadmium dose, bi-infection induced only slight, significant increased cell damage in G. roeseli as compared to non-infection. In addition, the antitoxic defence pattern of cadmium-exposed bi-infected ho…
Notulae to the Italian alien vascular flora: 2
2016
In this contribution, new data concerning the Italian distribution of alien vascular flora are presented. It includes new records, exclusions and confirmations for Italy or for Italian administrative regions for taxa in the genera Ageratum, Aster, Buddleja, Cedrus, Centranthus, Cephalotaxus, Clerodendrum, Cotoneaster, Cyperus, Honorius, Lantana, Ligustrum, Morus, Muscari, Oenothera, Opuntia, Platycladus, Plumbago, Pseudotsuga, Sedum, Sporobolus, Stachys, Ulmus and Yucca. A nomen novum, Stachys talbotii, is proposed as a replacement name for Sideritis purpurea.
Hybrid Deep Shallow Network for Assessment of Depression Using Electroencephalogram Signals
2020
Depression is a mental health disorder characterised by persistently depressed mood or loss of interest in activities resulting impairment in daily life significantly. Electroencephalography (EEG) can assist with the accurate diagnosis of depression. In this paper, we present two different hybrid deep learning models for classification and assessment of patient suffering with depression. We have combined convolutional neural network with Gated recurrent units (RGUs), thus the proposed network is shallow and much smaller in size in comparison to its counter LSTM network. In addition to this, proposed approach is less sensitive to parameter settings. Extensive experiments on EEG dataset shows…
On the Influence of Affect in EEG-Based Subject Identification
2021
Biometric signals have been extensively used for user identification and authentication due to their inherent characteristics that are unique to each person. The variation exhibited between the brain signals (EEG) of different people makes such signals especially suitable for biometric user identification. However, the characteristics of these signals are also influenced by the user’s current condition, including his/her affective state. In this paper, we analyze the significance of the affect-related component of brain signals within the subject identification context. Consistent results are obtained across three different public datasets, suggesting that the dominant component of the sign…