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This paper addresses the characterisation and analysis of a 2-collinear-DoF strut with embedded electromagnetic shunt dampers. The use of a negative resistance in the shunt circuit has been proved to considerably enhance the damping performance of this kind of electromagnetic dampers. The analytical model is reported and the theoretical results are compared with other damping methods. This work demonstrates the feasibility of achieving a remarkable decay rate of -80 dB/decade with a device that is smaller than previously-presented active struts and does not require complex electronics to operate.

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A large-scale database concerning benthic copepods from the Arctic, Baltic Sea, North Sea, British Isles, Adriatic Sea and Crete was compiled to assess species richness, biodiversity, communities, ecological range size and biogeographical patterns. The Adriatic showed the highest evenness and the most species-rich communities. Assemblages from the North Sea, British Isles, Baltic and Crete had a lower evenness. The British Isles were characterised by impoverished communities. The ecological specificity of copepod species showed two diverging trends: higher specificity of species in more diverse assemblages was observed in the Adriatic, North Sea and Baltic. A uniformly high species specificity disregarding sample diversity was found on Crete and in the British Isles. Benthic copepod communities showed distinct patterns that clearly fit the predefined geographical regions. Communities were distinguishable and ß-diversity was found to be high around Europe, indicating a high species turnover on the scale of this investigation. The British Isles and the North Sea were found to be faunistic links to the Baltic and the Arctic.

Recent biodiversity research reveals that more than 50% of the free-living marine nematode species found in before unexplored environments, such as Antarctica, are new to science. Too few taxonomists remain to describe them all. Additionally, there are problems with the quality control of the identification of nematode samples since fewer labs possess all the literature (and manpower) required to verify the morphological characteristics of the animals.NEMASLAN, software for a tree-based classification system (Access) is a methodological approach for improving identification, classification and description of specimens in difficult taxonomic groups such as free-living marine nematodes. It seeks to serve as an easy research tool for central management of information of the taxon of the nematodes, and this for people with little training in database technologies.The program consists of four main modules: (see demonstration)1. Module for data- entering: provides possibilities to enter geographic, morphological, ecological, and literature data on species in a record database. An additional connection between these database records and the actual digital sources (e.g. scanned literature from original descriptions and good recent publications) enlarges the scientific value of the system.Personal metadatasets can be created, for example for the use of drawings and/or pictures of undescribed species or not yet published taxonomic papers. 2. Module for document consultation: data sources (PDF documents of original descriptions, text documents, photographs,…) and their references can be consulted. 3. Module for Quick Search: Morphological data from the species identification (e.g. shape and/or position of amphid, cuticle, buccal cavity, tail, oesophagus, caudal glands and spinneret; feeding type; numerical fields of de Man ratios, length, setae, nerve ring, excretory porus, spicule, gubernaculum, male supplements) and other information such as type of biotope and water depth distribution can be consulted; datasheets can be generated.4. Search Module: The output and search within the database can be user configured (i.e. questions like ‘give me all the nematode species so far described from the coastal sites with a spicule longer than 30µm and cuticular punctuations’ get an answer from this database). SQL (Structured Query Language) is the formal language used to query databases. An in-depth knowledge of the fairly complex SQL language is not required.The Windows application functions for multi-users in a local network environment (LAN). The program is distributed free of charge through a website (at present http://allserv.rug.ac.be/~tdeprez: later on through a more specified Antarctic database website) at which demonstration datasets are distributed.NEMASLAN was applied to Antarctic nematodes. The resulting ‘Biodiversity of Antarctic Nematodes’ CD-ROM version includes an archive of all numerical and nominal information for each species ever described in the Southern Ocean. About 350 species have thus been digitized. There is an urgent need to develop appropriate information tools on Antarctic marine biodiversity for scientific, environmental management and conservation purposes. Therefore, the collaboration of three laboratory pioneers in Antarctic biodiversity databases (e.g. Antarctic nematodes, amphipods and echinids, see other presentations) will seek for further developments such as the construction of a common portal, common mapping applications, or links to pertinent information sources of Antarctic benthic biodiversity. The resulting ‘biodiversity information system’ will be made available to the scientific community. This will be done within the framework of the OSTC project on Antarctica - BIANZO (BIodiversity of three representative groups of the ANtarctic ZOobenthos). It will contribute to the DIVERSITAS, SA 2000, CoML-OBIS and GBIF initiatives.

During many years of extensive research at the Marine Biology Section (Ghent University) an almost complete collection of reprints on free-living marine Nematodes was built up. This collection still grows and more people are getting involved with it. Keeping the collection preserved for the future becomes a main worry. Therefore about four years ago we started making the collection also digitally available.A software developer was contacted and given the task to write an application corresponding to the needs formulated by the future users:· Input of taxonomic data must be possible in an easy way (through a taxonomical tree structure)· Availability of morphological, ecological and distribution data at the species level· Connection to the data source (digitally available) must be kept at any time· Data access and input in a network environment had to be possibleSoftware was developed and data input was started. Confronted with data-input new questions and worries evolved, which had to be translated into software changes. NemasLan was born.Two years later, interest was growing on starting a similar dataset on Mysidacea. Software had to be rewritten and new concepts were added corresponding to the needs for this taxon. MysidLan was born. After working with both systems for about three years (each with their own software code), it was decided to create a generic system based on the former two systems but easily adaptable for datasets of other groups.TaxonLan was born, but was aching of lot of child diseases.As time went by, a big evolution within the world of taxonomic databases took place. All over the world similar projects arose and also in Belgium structural steps were taken through/by means of the establishment of a data center (VLIZ - Flanders Marine Institute).Communication between different authorities, developing and working with taxonomical databases, as well as the growing expertise within our laboratory and the enormous costs associated with software development, made us decide to stop collaborating with a commercial software developer. The created datasets will be fine-tuned into a general database structure (as being used by the VLIZ or IT IS). By heading in this direction we hope our data becomes more than an exclusive dataset for our laboratory/department and new possibilities will arise.

The list was compiled by Guy De Smet, a non-specialist, who was assisted by nematologists Magda Vincx, Ann Vanreusel, Sandra Vanhove, Jan Vanaverbeke and Maaike Steyaert. Dr. F. Riemann gave useful advice for the genus Daptonema. The classification in the list is based upon Lorenzen (1979, 1994). Information on the geographic distribution in the list is based upon Gerlach and Riemann (1973, 1974), Platt and Warwick (1983, 1988) and Warwick et al. (1998).ReferencesLorenzen, S. Entwürf eines Phylogenetischen Systems der Freilebenden Nematoden, Kiel, 1979.Lorenzen, S. The Phylogenetic Systematics of Freeliving Nematodes, The Ray Society, 1994.Gerlach, S. A. and Riemann, F. The Bremerhaven Checklist of Aquatic Nematodes. Veröffentlichungen des Instituts für Meeresforschung in Bremerhaven, Supplement 4, (Heft 1 1973, Heft 2 1974).Platt, H. M. and Warwick, R. M. Free-living Marine Nematodes (Part I British Enoplids) Synopses of the British Fauna (New series) No. 28, 1983.Platt, H. M. and Warwick, R. M. Free-living Marine Nematodes (Part II British Chromadorids) Synopses of the British Fauna (New series) No. 38, 1988.Warwick, R. M., Platt, H. M. and Somerfield, P. J. Free-living Marine Nematodes (Part III Monhysterids) Synopses of the British Fauna (New series) No. 53, 1998.

In 1988 and 1989~ 4 extra stations situated west of the TiO2-dumping site, were sampled for reason of getting adequate reference stations out of possible influence of the dutch and belgian dumping grouds.According to the sediment analysis, these stations are comparable to the stations within the dumping area and can be regarded as reference stations.The vertical distribution of the meiobenthos was investigated for 10 stations, 5 situated within the dumping area and 5 situated westwards. Nematoda, Capepoda, Gastrotricha and Turbellaria did occur until 20 cm deep; Tardigrada, Hydrozaa, Ostracoda, Halacarida and Rotifera were confined to the upper 15 cm. At least the upper 10 cm of the sediment was oxigenated.Within the dumping area the highest percentage of meiofauna occured in the 5-10 cm layer, whereas in the reference area the highest percentages occured in the layers 0-2 cm and 2-5 cm.There was a significant difference between the dumping area and the reference area for the parameter mean density of the total meiafauna, the nematods, the copepods and the turbellarians af the uppermost 10 cm layers (0-2 cm, 2-5 cm, 5-10 cm; nematods only in 0- 2 cm).