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In the lower siliceous uplands of Central Europe, various types of nutrient-poor grasslands are widespread and grow intermingled. These species-rich grasslands, often dominated by taxa of the Festuca ovina aggregate, comprise various phytosociological classes. They are remnants of a historic rural lands - cape and are of conservation importance. Few studies on such grasslands are available and there has been disagreement in assigning them to appropriate habitat types or syntaxa. We investigated such nutrient-poor grasslands in the lower Aar valley (Middle Hesse, Rhenish Massif). We surveyed 104 vegetation plots distributed throughout the valley and identified syntaxa to (sub)association level. We carried out supervised classification combining cluster analysis, a priori assignment to classes based on prevailing diagnostic species, and regional refinement based on phi-value maximisation of the units. As a result, we classified five associations within four classes: Polytricho piliferi-Festucetum tenuifoliae/Galio harcynici-Deschampsietum flexuosae and Festuco rubrae-Genistelletum sagittalis (Calluno- Ulicetea), Jasiono montanae-Festucetum ovinae (Koelerio-Corynephoretea), Gentiano-Koelerietum pyramidatae (Festuco-Brometea) and Arrhenatheretum elatioris (Molinio-Arrhenatheretea). Ecologically, soil acidity (resulting from Ca concentrations of the bedrock) was the main cause of floristic dissimilarity of the grasslands and thus community differentiation. Many stands grew on soils with intermediate pH and showed a peculiar mixture of basiphilous and acidophilous species. We conclude that (i) our approach of supervised classification yields convincing reproducible results when a syntaxonomic system is adapted top-down to a geographically restricted area, (ii) nutrient-poor siliceous grasslands dominated by taxa of the Festuca ovina aggregate can be well assigned to ecologically meaningful syntaxa, and (iii) the nutrient-poor siliceous grasslands of the Lahn-Dill Highlands are of high conservation relevance and in urgent need of protection.
Despite good clinical functional outcome, deficits in gait biomechanics exist 2 years after total hip replacement surgery. The aims of this research were (1) to group patients showing similar gait adaptations to hip osteoarthritis and (2) to investigate the effect of the surgical treatment on gait kinematics and external joint moments. In a secondary analysis, gait data of 51 patients with unilateral hip osteoarthritis were analyzed. A k-means cluster analysis was performed on scores derived via a principal component analysis of the gait kinematics. Preoperative and postoperative datasets were statistically tested between clusters and 46 healthy controls. The first three principal components incorporated hip flexion/extension, pelvic tilt, foot progression angle and thorax tilt. Two clusters were discriminated best by the peak hip extension during terminal stance. Both clusters deviated from healthy controls in spatio-temporal, kinematic and kinetic parameters. The cluster with less hip extension deviated significantly more. The clusters improved postoperatively but differences to healthy controls were still present one year after surgery. A poor preoperative gait pattern in patients with unilateral hip osteoarthritis is associated with worse gait kinematics after total hip replacement. Further research should focus on the identification of patients who can benefit from an adapted or individualized rehabilitation program.
Despite their vast distribution ranging from Central Europe to Siberia, hemiboreal oligotrophic pine forests remain poorly studied. Though they dependence on low productive soils, they are widespread on sandy deposits or in bogs. This study aims to classify and ecologically describe the vegetation of oligotrophic pine forests in the south of Western Siberia.
In total 50 relevés from nutrient-poor sandy substrates and bogs were sampled in the pre-Taiga zone of the Tyumen province covering the whole range from dry to wet habitats. Five vegetation types were defined by hierarchical clustering. Phi coefficient of association was calculated for groups and their combination, resulting in a high number of species with high fidelity to clusters. Floristic composition ranged from xero-mesophytic vegetation with high frequency of the tribe Pyroleae on dry sandy soils to pine-sphagnum-communities on bogs. The strongest environmental gradients influencing the floristic composition were soil humidity, nutrient supply and fire. Higher nutrient supply due to loamy subsoil increased vascular plant species richness, enabling common plants of hemiboreal birch forests to grow.
Surface fires turned out to be a key process in dry pine forests, resulting in a destroyed bryophyte layer and to a partly altered vascular plant species composition. Fire regime plays an important role in maintaining the floristic composition and habitat structure over time. West-Siberian dry oligotrophic pine forests are ecologically, structurally and floristically quite similar to Central-European pine communities of the Peucedano-Pinetum.
This checklist of the lichens and Iichenicolous fungi of Chile (including the Antarctic ten-itory, Juan Fernandez and Easter island) includes 1415 taxa in 304 genera of which 1383 are lichens (in 281 genera), and 32 are lichenicolaus fungi (in 23 genera). Full bibliographic citations are given for both accepted taxa and for synonyms and references to relevant literature are included for most genera. The following new combinations are proposed: Caloplaca austroshetlandica (Zahlbr.) D.J. Galloway & Quilhot, Dendriscocaulon calithamnion (Taylor) D.J. Galloway & Quilhot, Neuropogon durietzii (Motyka) D.J. Galloway & Qllilhot, Neuropogon patagonicus (F.J. Walker) DJ. Galloway & Quilhot, and Neuropogon subamarcticus (F. J. Walker) D.,T. Galloway & Quilhot.
Species of Calloeneis Grote (Coleoptera: Coccinellidae) are discussed, and a key to all recognized species is provided. New species described are C. alexandra, C. angelica, C. blanca, C. bennetti, C. bethany, C.brooke, C. francis, C. jacquelin, C. johnnie, C. kara, C. krista, C. leticia, C. lynne, C. robyn, C. marianne, C. myra,C. rosalie, C. roxanne and C. sheri, all authored by Gordon and Hanley.
Twenty new species are described in Pentilia Mulsant (Coleoptera: Coccinellidae: Scymninae: Cryptognathini) by Gordon and González: Pentilia bernadette, P. chelsea, P. dianna, P. elena, P. ernestine, P. estelle, P. kari, P. jasmine, P. jody, P. kendra. P. krystal, P. lora, P. mable, P. muriel, P. nichole, P. nadine. P. paulette, P. rachael, P. sadie and P. traci. A lectotype is here designated for Pentilia egena Mulsant.
The Japanese micropterigid moths are revised. Seventeen species in five genera are recognized from Japan, described or redescribed with the male and female genital figures. Of these, two genera, Issikiomartyria HASHIMOTO and Kurolkopteryx HASHIMOTO, and seven species, Issikiomartyria akemiae HASHIMOTO, Issikiomartylia plicata HASHIMOTO, Issihiomartyria distincta HASHIMOTO, Issihiomartyria bisegmentata HASHIMOTO, Kurokopteryx dolichocerata HASHIMOTO, Neomicropteryx hiwana HASHIMOTO, and Neomicropteryx redacta HASHIMOTO, are new to science. A new combination is given: Issikiomartyria nudata (Issuu). Biology and immature structures of the Japanese species are also described together with the keys to genera and to species provided on the basis of the adult characters. Phylogenetic relationships among the Northern Hemisphere genera are analyzed by the cladistic analysis using PAUP* (SWOFFORD, 2002) based on the morphological characters of adults. A monophyly of the Northern Hemisphere genera except for Micropterix is supported by nine apomorphies, but their immediate sister taxon remains unresolved.
Marginal associations, i.e. floristically impoverished associations at the margin of the distribution area of a higher syntaxon, form a problem in vegetation classification, because true character species are lacking. We propose a new approach for the classification of such marginal associations, making use of the notion of 'chorological tension zones'. In the absence of true character species, the species from other syntaxa of the same formation can be used as such. Our proposal is to use the species group from every formation-true class only once within every marginal alliance, to limit the number of possible marginal associations. This approach is illustrated in a classification of the retamoid thickets in the Netherlands. On the basis of a numerical-subjective classification of the relevant species in the scrub layer and the evaluation of relevant literature, we conclude that the broom and gorse thickets in the Netherlands can be assigned to the Cytisetea scopario-striati Rivas-Mart. 1974, which is represented by four associations, each of which is characterised by the species of other scrub classes. The Ulici europaei-Sarothamnion scoparii Doing ex Weber 1997 is represented by the Rubo plicati-Sarothamnetum scoparii Weber 1987 and the Crataego monogynae-Cytisetum scoparii R. Haveman, I. de Ronde & J.H.J. Schaminée ass. nov., the Ulici europaei-Cytision striati Rivas-Mart., Báscones, Díaz, Fern. Gonz. & Loidi 1991 by the Frangulo alni-Ulicetum europaei De Foucault 1988 and the Rubo ulmifolii-Ulicetum europaei J.-M. Géhu ex R. Haveman, I. de Ronde & J.H.J. Schaminée ass. nov. This classification is based on a restricted dataset though, and a revision, based on a larger dataset from a wider region has to prove the tenability of the classification.
The selection of features for classification, clustering and approximation is an important task in pattern recognition, data mining and soft computing. For real-valued features, this contribution shows how feature selection for a high number of features can be implemented using mutual in-formation. Especially, the common problem for mutual information computation of computing joint probabilities for many dimensions using only a few samples is treated by using the Rènyi mutual information of order two as computational base. For this, the Grassberger-Takens corre-lation integral is used which was developed for estimating probability densities in chaos theory. Additionally, an adaptive procedure for computing the hypercube size is introduced and for real world applications, the treatment of missing values is included. The computation procedure is accelerated by exploiting the ranking of the set of real feature values especially for the example of time series. As example, a small blackbox-glassbox example shows how the relevant features and their time lags are determined in the time series even if the input feature time series determine nonlinearly the output. A more realistic example from chemical industry shows that this enables a better ap-proximation of the input-output mapping than the best neural network approach developed for an international contest. By the computationally efficient implementation, mutual information becomes an attractive tool for feature selection even for a high number of real-valued features.
The Lycocerus hanatanii species group is revised, with the addition of seven taxa: L. araticollis (Fairmaire, 1897), L. nigripennis (Pic, 1938), L. griseopubens (Pic, 1928), L. yitingi Hsiao & Okushima sp. nov., L. aurantiacus Hsiao & Okushima sp. nov., L. evangelium Hsiao & Okushima sp. nov. and L. kintaroi Hsiao & Okushima sp. nov. Supplementary descriptions of the males of L. araticollis and L. griseopubens are provided. Lycocerus nigripennis (Pic, 1938) and L. pictus (Wittmer, 1983) are redescribed in detail. Each species is provided with photos or illustrations of genitalia of both sexes and abdominal ventrite VII of the female if available. Distribution maps and a key to the species of the L. hanatanii species group are presented. In addition, the monophyly of the L. hanatanii species group is supported based on a morphological phylogenetic analysis.