Fauna trematoda kod nekih vrsta riba u reci Spreči

U radu su prikazane trematode koje su nađene kod riba u reci Streči tokom ihtioparazitoloških ispitivanja. Parazitološka ispitivanja su obavljena tokom 2010. godine i pokazala su prisustvo parazita kod 7 vrsta riba od 11 pregledanih u reci Streči tj. 144 primerka je bilo zaraženo trematodama od ukupnog broja (365) ispitanih riba. Kod pet vrsta riba nađene su dve vrste monogenih trematoda (Dactylogyrus sp., Gyrodactylus sp.) odnosno u crvenperki, deveriki, šaranu, ukliji i klenu. Digene trematode (Diplostomum spathaceum, Posthodiplostomum cuticola) zarazile su 6 vrsta riba u reci Spreči, odnosno crvenperku, deveriku, podusta, babušku, ukliju i klena. Najjača zaraza je nađena kod Leuciscus cephalus (63,63 %) i Chondrostoma nasus (54,54 %) Nešto slabiji stepen infekcije kod Scardinius erythrophthalmus, Abramis brama i Alburnus alburnus. Najmanja zaraženost je bila kod Cyprinus carpio i Carassius gibelio. Kod drugih vrsta riba nisu nađeni paraziti tokom perioda ispitivanja. Od pojedinačnih tipova trematoda najveći obim infekcije je bio sa Diplostomum spathaceum (14,79 %) i Dactylogrus sp. (12,86 %) a najmanji sa Gyrodactylus salaris, samo 1,91 %. Intenzitet zaraze kod ispitivanih riba varirao je od slabog pa sve do visokog stepena infestacije. Obim infestacije je zavisio od sezone ispitivanja

Parasites of non-native freshwater fishes introduced into england and wales suggest enemy release and parasite acquisition

When non-native species are introduced into a new range, their parasites can also be introduced, with these potentially spilling-over into native hosts. However, in general, evidence suggests that a high proportion of their native parasites are lost during introduction and infections by some new parasites from the native range might occur, potentially resulting in parasite spill-back to native species. These processes were investigated here using parasite surveys and literature review on seven non-native freshwater fishes introduced into England and Wales. Comparison of the mean numbers of parasite species and genera per population for each fish species England andWaleswith their native ranges revealed\9 % of the native parasite fauna were present in their populations in England and Wales. There was no evidence suggesting these introduced parasites had spilled over into sympatric native fishes. The non-native fishes did acquire parasites following their introduction, providing potential for parasite spill-back to sympatric fishes, and resulted in non-significant differences in overall mean numbers of parasites per populations between the two ranges. Through this acquisition, the non-native fishes also had mean numbers of parasite species and genera per population that were not significantly different to sympatric native fishes. Thus, the non-native fishes in England and Wales showed evidence of enemy release, acquired new parasites following introduction providing potential for spill-back, but showed no evidence of parasite spill-over

The populist radical right in government: The structure and agency of success and failure

Contains fulltext : 111905.pdf (publisher's version ) (Closed access)25 juli 201128 p

The Visualization of Migration

This article focuses on the election posters for the initiative Gegen Masseneinwanderung ( Against Mass Immigration ) launched by the national conservative Swiss People’s Party (Schweizer Volkspartei) in February 2014. Based on qualitative visual analysis, I discuss how sociospatial phenomena are visualized to convey political messages. First, I undertake the important task of identifying discursive and visual elements of the image, as well as the image–text pattern in order to understand how meaning is created. Second, I investigate the concrete praxis of the image: How do images argue, substantiate, and demonstrate in a way that allows viewers to make meaning out of them? Third, I follow a productive step of contextualizing the praxis of the image. To understand how visual messages are effectively conveyed, and how images help to create a politically strategic context and persuade viewers, involves examining the narratives and contexts that the images rely on in order to be understood by viewers. Visual analysis allows for insights into the ways in which visual constructions of reality are created. Furthermore, this article offers methodological strategies that are key to understanding how images are used to depict and construct realities and how these realities are accepted as true, as it is the case with the posters designed for the Against Mass Immigration initiative