Document Server@UHasselt
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Repository of the University of Hasselt containing publications in the fields of statistics, computer science, information strategies and material from the Institute for behavioural sciences.
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1.
Filling a gap in the phylogeny of flatworms: relationships within the Rhabdocoela (Platyhelminthes), inferred from 18S ribosomal DNA sequences - WILLEMS, Wim; Walberg, A.; Jondelius, U.; Littlewood, D.; Backeljau, T.; SCHOCKAERT, Ernest; ARTOIS, Tom
The phylogeny of the Rhabdocoela, a species-rich taxon of free-living flatworms, is reconstructed
based on complete 18S rDNA sequences. The analysis includes 62 rhabdocoels
and 102 representatives of all major flatworm taxa. In total, 46 new sequences are used, 41 of them
from rhabdocoel species, five from proseriates. Phylogenetic analysis was performed using
maximum parsimony and Bayesian inference. Clade support was evaluated with parsimony
jackknifing, Bremer support indices and Bayesian posterior probabilities. The resulting cladogram
corroborates that the Rhabdocoela is monophyletic, but its sister group remains uncertain.
The Dalyellioida and the Typhloplanoida, both former rhabdocoel subtaxa, are
polyphyletic. Within the Rhabdocoela the monophyletic Kalyptorhynchia, characterized by a
muscular proboscis,...
2.
Cirrifera genitoductus sp.n. (Platyhelminthes, Proseriata, Coelogynoporidae) from the Belgian coast, with observations on its ultrastructure and its significance for the taxonomy of the Coelogynoporidae - Jouk, Philippe E. H.; MARTENS, Els; SCHOCKAERT, Ernest
Cirrifera genitoductus sp.n. (Platyhelminthes, Proseriata, Coelogynoporidae) is described from sandy beaches at the Belgian and Northern French coasts. The species is characterised by a cirrus with small spines, all of the same size, a prostate vesicle far behind the copulatory bulb, a long genito-intestinal duct and a pair of large gland complexes behind the genital pore. An identification key for the Cirrifera-species is given as are some data on the ultrastructure. A brief discussion on the character distribution within the Coelogynoporidae shows that the discovery of a species of Cirrifera with a genito-intestinal duct makes the demarcation of the genera...
3.
Filling a gap in the phylogeny of flatworms: relationships within the Rhabdocoela (Platyhelminthes), inferred from 18S ribosomal DNA sequences - WILLEMS, Wim; Walberg, A.; Jondelius, U.; Littlewood, D.; Backeljau, T.; SCHOCKAERT, Ernest; ARTOIS, Tom
The phylogeny of the Rhabdocoela, a species-rich taxon of free-living flatworms, is reconstructed
based on complete 18S rDNA sequences. The analysis includes 62 rhabdocoels
and 102 representatives of all major flatworm taxa. In total, 46 new sequences are used, 41 of them
from rhabdocoel species, five from proseriates. Phylogenetic analysis was performed using
maximum parsimony and Bayesian inference. Clade support was evaluated with parsimony
jackknifing, Bremer support indices and Bayesian posterior probabilities. The resulting cladogram
corroborates that the Rhabdocoela is monophyletic, but its sister group remains uncertain.
The Dalyellioida and the Typhloplanoida, both former rhabdocoel subtaxa, are
polyphyletic. Within the Rhabdocoela the monophyletic Kalyptorhynchia, characterized by a
muscular proboscis,...
4.
First report on Rhabdocoela (Rhabditophora) from deep parts of Skagerrak, with the description of four new species - WILLEMS, Wim; Sandberg, Maria; Jondelius, Ulf
In this contribution we report on 13 species of Rhabdocoela, found during a marine inventory of Skagerrak by the Swedish Taxonomy Initiative. Four new species are described, two of which are Kalyptorhynchia (Gnathorhychidae and Polycystididae) and two belong to Dalytyphloplanoida (Solenopharyngidae). Uncinorhynchus vorago sp. nov., (Gnathorhynchidae) has a triangular stylet consisting of a double-folded plate, which proximally forms a tube, but without a distal, needle-shaped tip. Austrorhynchus artoisi sp. nov. (Polycystididae), has two prostate stylets. Prostate stylet type II consists of a distal tube and a short proximal funnel, which has a stirrup-shaped ornament, whereas the stylet type III shows...
5.
A new family of litophoran Proseriata (Platyhelminthes), with the description of seven new species from the Indo-Pacific and South America, and the proposal of three new genera - SCHOCKAERT, Ernest; Curini-Galletti, M.; De Ridder, W.; Volonterio, O.; ARTOIS, Tom
In this contribution a new representative of the taxon Meidiama Marcus, 1946, Meidiama uruguayensis sp. nov., from Uruguay, is described, as are six more new species, for which three new genera are proposed: Dreuxiola philippi gen. nov. sp. nov., from the French subantarctic archipelago Kerguelen; Yorknia aprostatica gen. nov. sp. nov.; Serrula byronensis gen. nov. sp. nov.; Serrula maxillaria sp. nov.; Serrula concharum sp. nov.; and Serrula acuta sp. nov., from eastern Australia and Tasmania. Arguments are presented to propose a new taxon to contain these new species, rather than include them in the Archimonocelididae Meixner, 1938 (of which Meidiama...
6.
Use of freeze-cracking in ontogenetic research in Macrostomum lignano (Macrostomida, Rhabditophora) - Willems, Maxime; Boone, Mieke; Couvreur, Marjolein; De Mulder, Katrien; Van Ranst, Jelka; ARTOIS, Tom; Borgonie, Gaetan
A method for studying whole mount flatworm embryos based on freeze-cracking of the eggs is described. This method allows successful immunohistological and immunocytological studies of whole mount embryos. It does not require the use of sharpened needles or a microinjection system to puncture the eggshell. Moreover, this method is more practical and less time-consuming than classical puncturing and much cheaper than the use of a microinjection system. The advantages of this method are illustrated by results of several immunolocalisation experiments in the macrostomid flatworm Macrostomum lignano. The optimal procedure and crucial steps for this method are discussed.
7.
House dust as possible route of environmental exposure to cadmium and lead in the adult general population - Hogervorst, Janneke; PLUSQUIN, Michelle; VANGRONSVELD, Jaco; Nawrot, Tim; CUYPERS, Ann; Van Hecke, Etienne; Roels, Harry; CARLEER, Robert; Staessen, Jan
Contaminated soil particles and food are established routes of exposure. We investigated the relations between biomarkers of exposure to cadmium and lead, and the metal loading rates in house dust in the adult residents of an area with a soil cadmium concentration of >= 3 mg/kg (n = 268) and a reference area (n = 205). We determined the metal concentrations in house dust allowed to settle for 3 months in Petri dishes placed in the participants' bedrooms. The continuously distributed vegetable index was the first principal component derived from the metal concentrations in six different vegetables. The biomarkers of...
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