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Using the internet to aid in discovery of unrecognized type material
No full textSteudel, Bastian, Kessler, Michael, Nyffeler, Reto (2012): Using the internet to aid in discovery of unrecognized type material. Phytotaxa 62 (1): 13-24, DOI: 10.11646/phytotaxa.62.1.4, URL: http://biotaxa.org/Phytotaxa/article/view/phytotaxa.62.1.
Using the internet to aid in discovery of unrecognized type material
No full textHerbaria contain many specimens for which identification to species and family is not up-to-date with current classifications. However, updated species names are essential as key information for publishing digitized specimen data on internet-based online resources such as Global Biodiversity Information Facility (GBIF; www.gbif.org). Keeping herbarium collections current relative to classification of species and families poses a particular challenge to herbarium staff. Especially, families with a dynamic record of repeated changes in generic classification, such as Orchidaceae, require much curatorial attention. We used the World Checklist of Selected Plant Families (WCL; apps.kew.org/wcsp/home.do) for rapid validation of current species names of specimens of Orchidaceae housed at the combined herbaria of the University of Zurich (Z) and the Swiss Federal Institute of Technology Zurich (ZT). In order to evaluate the possible type status of specimens, we consulted the original species description when the reviewed specimens were collected prior to the date of the publication. Within 600 hours of labour, we reviewed and updated species names for about 10,000 orchid specimens and located 280 previously unrecognized type specimens. Almost half of the type specimens located in the general collections represent species described by Rudolf Schlechter, Fritz Kraenzlin, and Rudolf Mansfeld, whose original material was destroyed in 1943 in the Herbarium Berolinense (B) and for which discovery at Z+ZT is therefore particularly valuable
Using the internet to aid in discovery of unrecognized type material
No full textHerbaria contain many specimens for which identification to species and family is not up-to-date with current classifications. However, updated species names are essential as key information for publishing digitized specimen data on internet-based online resources such as Global Biodiversity Information Facility (GBIF; www.gbif.org). Keeping herbarium collections current relative to classification of species and families poses a particular challenge to herbarium staff. Especially, families with a dynamic record of repeated changes in generic classification, such as Orchidaceae, require much curatorial attention. We used the World Checklist of Selected Plant Families (WCL; apps.kew.org/wcsp/home.do) for rapid validation of current species names of specimens of Orchidaceae housed at the combined herbaria of the University of Zurich (Z) and the Swiss Federal Institute of Technology Zurich (ZT). In order to evaluate the possible type status of specimens, we consulted the original species description when the reviewed specimens were collected prior to the date of the publication. Within 600 hours of labour, we reviewed and updated species names for about 10,000 orchid specimens and located 280 previously unrecognized type specimens. Almost half of the type specimens located in the general collections represent species described by Rudolf Schlechter, Fritz Kraenzlin, and Rudolf Mansfeld, whose original material was destroyed in 1943 in the Herbarium Berolinense (B) and for which discovery at Z+ZT is therefore particularly valuable
August Wulfhorst (1861-1936) and his overlooked contributions on the flora of Angola
No full textFigueiredo, Estrela, Smith, Gideon F., Nyffeler, Reto (2013): August Wulfhorst (1861-1936) and his overlooked contributions on the flora of Angola. Candollea 68 (1): 123-131, DOI: 10.15553/c2013v681a1
Fig. 2 in August Wulfhorst (1861-1936) and his overlooked contributions on the flora of Angola
No full textFig. 2. – Holotype of Wulfhorstia spicata C. DC. (Z000015223), showing original and replacement labels.Published as part of Figueiredo, Estrela, Smith, Gideon F. & Nyffeler, Reto, 2013, August Wulfhorst (1861-1936) and his overlooked contributions on the flora of Angola, pp. 123-131 in Candollea 68 (1) on page 126, DOI: 10.15553/c2013v681a17, http://zenodo.org/record/603945
Different Modeling Strategies for Discrete Choice Models of Female Labour Supply: Estimates for Switzerland
Full text linkIn recent applications of discrete choice models of labour supply considerable attention has been devoted to strategies to increase the flexibility of models for a better fit to the data. These include the introduction of random parameters, fixed cost of work or flexible functional forms of preferences. Based on estimates of models of recent studies this paper compares these different modeling strategies. Results for Swiss data show that the traditional way to interpret fixed cost of work is ad hoc. Furthermore our results indicate that care should be taken when using very general function forms of preferences
Berufliche Weiterbildung in der Schweiz
Full text linkBerufliche Weiterbildung spielt in der modernen Arbeitswelt eine zentrale Rolle bei der Entwicklung der beruflichen Fähigkeiten von Arbeitnehmern und hat daher potentiell grosse Auswirkungen auf deren Chancen im Arbeitsmarkt. Die vorliegende Arbeit bietet eine deskriptive Analyse des Weiterbildungsverhaltens in der Schweiz und untersucht anhand ökonometrischer Schätzungen die Auswirkungen beruflicher Weiterbildung auf die Löhne der Arbeitnehmer. Die dazu verwendeten Daten stammen von den Befragungswellen 98, 99 und 2000 der Schweizerischen Arbeitskräfteerhebung (SAKE). Da davon auszugehen ist, dass die Teilnahme an beruflicher Weiterbildung nicht zufällig, sondern Ergebnis rationaler Entscheidungen von Arbeitgebern und Arbeitnehmern ist, kann Weiterbildung nicht als eine exogene Determinante des Lohnes betrachtet werden. Eine Schätzung der Mincer Lohngleichung mittels OLS fuhrt daher zu verzerrten Schätzern. Zur Entschärfung des Endogenitätsproblems wird in dieser Arbeit ein Fixed effects Modell verwendet. Die Schätzergebnisse implizieren eine
Weiterbildungsrendite von ungefähr 2%, was deutlich tiefer ist als die bisher fur die Schweiz vorliegenden Schätzungen
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Nolina RUSCACEAE
No full textA diagnostic description of the genus is given with special emphasis on the occurrence of succulence amongst its species. The geographical distribution is outlined, together with a selection of important literature, and an explanation of the etymology of the name. This is followed by a short summary of its position in the phylogeny of the family and of the past and present classification in a phylogenetic context. The succulent features present amongst the species of the genus are shortly explained as to morphology and anatomy.
This is followed by a synoptical treatment of the succulent species of the genus, complete with typification details, full synonymy, geographical and ecological data, a diagnostic description, and, where applicable, notes on phylogenetic placement and relationships, as well as economic and/or horticultural importance
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