TY  - JOUR
A1  - Moll, Heidrun
A1  - Fuchs, Harald
A1  - Blank, Christine
A1  - Röllinghoff, Martin
T1  - Langerhans cells transport Leishmania major from the infected skin to the draining lymph node for presentation to antigen-specific T cells
N2  - No abstract available
KW  - Immunologie
KW  - Langerhans cell
KW  - Leishmania major
KW  - T-cell
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-46023
ER  - 
TY  - JOUR
A1  - Krüger, Hans-Peter
T1  - Simultane U-Tests zur exakten Prüfung von Haupt- und Wechselwirkungen in 2x2-faktoriellen Versuchsplänen
N2  - Ausgehend von einem Ansatz zur nichtparametrischen Prüfung von Wechselwirkungen (BREDENKAMP, 1974), der nur unter asymptotischen Bedingungen gilt, wird empfohlen, auf Wechselwirkung in dem praktisch wichtigen 22 -faktoriellen Versuchsplan exakt dadurch zu prüfen, daß man die Diagonalzellen überkreuzend zusammenfaßt und mittels V-Test (Cross-Over-V-Test) auf Lageunterschiede prüft. Zugleich kann durch Zeilen- und/oder Spaltenzusammenfassungen auf Hauptwirkungen geprüft werden. Drei simultane Tests können sodann eine parametrische ANOVA aussageinferentiell voll ersetzen! Die Durchflihrung der Tests wird an einem Beispiel illustriert. Zusätzlich wird auf die Möglichkeit der Prüfung auf Wechselwirkungen höherer Ordnung in 2n-faktoriellen Versuchsplänen hingewiesen.
N2  - According to the results of non-parametric interaction testing (BREDENKAMP, 1974) an attempt is made to test exactly the interaction in a 22 factorial design in which a-symptotic testing sensu Bredenkamp is in appropriate. Assuming A+ and A- as modalities of factor A and B+ and B- as modalities of factor B, cross-over pooling A+B+ A-B- versus A+B- A-B+ results in a two sampie U-test for differences in location which is equivalent to a test for interaction effects between A and B. In a similar way rows and columns may be pooled thus helping to develop exact tests for main effects of A and B. Thus ANOVA may be substituted by three simultaneous U-tests. The respective procedure is illustrated by a numerical example and may be generalized on 2n factorial designs.
Y1  - 1977
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41592
ER  - 
TY  - JOUR
A1  - Bonte, Dries
A1  - Clercq, Nele De
A1  - Zwertvaegher, Ingrid
A1  - Lens, Luc
T1  - Repeatability of dispersal behaviour in a common dwarf spider: evidence for different mechanisms behind short- and long-distance dispersal
N2  - Abstract: 1. The response of dispersal towards evolution largely depends on its heritability for which upper limits are determined by the trait's repeatability. 2. In the Linyphiid spider E. atra, we were able to separate long- and short-distance dispersal behaviours (respectively ballooning and rappelling) under laboratory conditions. By performing repeated behavioural trials for females, we show that average dispersal trait values decrease with increasing testing days. By comparing mated and unmated individuals during two periods (before and after mating for the mated group, and the same two periods for the unmated group), we show that mating has no effect on the mean displayed dispersal behaviour or its within-individual variation. Repeatabilities were high and consistent for ballooning motivation, but not for rappelling. 3. Ballooning motivation can be regarded as highly individual-specific behaviour, while general pre-dispersal and rappelling behaviours showed more individual variation. Such difference in repeatability between long-and short-distance dispersal suggests that short-and long-distance dispersal events are triggered by different ecological and evolutionary mechanisms.
Y1  - 2009
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-48242
ER  - 
TY  - JOUR
A1  - Bonte, Dries
A1  - Maes, Dirk
T1  - Trampling affects the distribution of specialised coastal dune arthropods
N2  - Abstract: From a conservation point of view, species- tolerances towards disturbance are often generalised and lack reference to spatial scales and underlying processes. In order to investigate how average typical species react to habitat fragmentation and disturbance, we adopted a multi-species approach to address occupancy patterns of five specialised dune arthropods (butterflies Hipparchia semele, Issoria lathonia; grasshopper Oedipoda caerulescens; spiders Alopecosa fabrilis, Xysticus sabulosus) in recently fragmented coastal dune habitats which are subjected to varying levels and modes of local disturbance, i.e. trampling by cattle or people. Occupancy patterns were assessed during two successive years in 133 grey dune fragments of the Flemish coastal dunes (Belgium, France). By treating species as a random factor in our models, emphasis was placed on generalisations rather than documenting species-specific patterns. Our study demonstrates that deteriorating effects of local disturbance on arthropod incidence cannot be interpreted independent of its landscape context, and appear to be more severe when patch area and connectivity decrease. When controlled for patch area and trampling intensity, the probability of species occupancy in poorly connected patches is higher under cattle trampling than under recreation. Incidences additionally decrease with increasing intensity of cattle trampling, but increases with trampling by tourists. This study provides evidence of mode- and landscape-dependent effects of local disturbance on species occupancy patterns. Most importantly, it demonstrates that trampling of sensitive dune fragments will lead to local and metapopulation extinction in landscapes where trampling occurs in a spatially autocorrelated way, but that the outcome (spatial patterns) varies in relation to disturbance mode, indicating that effects of disturbance cannot be generalised.
KW  - Araneae
KW  - grazing
KW  - grey dunes
KW  - Lepidoptera
KW  - multispecies metapopulation
KW  - Orthoptera
KW  - recreation
KW  - trampling
Y1  - 2008
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-48274
ER  - 
TY  - JOUR
A1  - Bonte, Dries
A1  - Lanckacker, Kjell
A1  - Wiersma, Elisabeth
A1  - Lens, Luc
T1  - Web building flexibility of an orb-web spider in a heterogeneous agricultural landscape
N2  - Abstract: Intensification of land-use in agricultural landscapes is responsible for a decline of biodiversity which provide important ecosystem services like pest-control. Changes in landscape composition may also induce behavioural changes of predators in response to variation in the biotic or abiotic environment. By controlling for environmentally confounding factors, we here demonstrate that the orb web spider Araneus diadematus alters its web building behaviour in response to changes in the composition of agricultural landscapes. Thereby, the species increases its foraging efficiency (i.e. investments in silk and web asymmetry) with an increase of agricultural land-use at intermediate spatial scales. This intensification is also related to a decrease in the abundance of larger prey. A negative effect of landscape properties at similar spatial scales on spider fitness was recorded when controlling for relative investments in capture thread length. This study consequently documents the web building flexibility in response to changes in landscape composition, possibly due to changes in prey availability.
KW  - Araneus diadematus
KW  - Araneidae
KW  - behavioural flexibility
KW  - orb web geometry
KW  - landscape
KW  - model selection
KW  - semi-natural habitats
Y1  - 2008
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-48262
ER  - 
TY  - JOUR
A1  - Will, Antje
A1  - Blank, Christine
A1  - Röllinghoff, Martin
A1  - Moll, Heidrun
T1  - Murine epidermal Langerhans cells are potent stimulators of an antigen-specific T cell response to Leishmania major, the cause of cutaneous leishmaniasis
N2  - Cutaneous leishmaniasis is initiated by the bite of an infected sandfly and inoculation of Leishmania major parasites into the mammalian skin. Macrophages are known to playa central role in the course of infection because they are the prime host cells and funetion as antigen-presenting eells (APC) for induetion of the eell-mediated immune response. However, in addition to maerophages in the dermis. the skin eontains epidermal Langerhans eells (LC) which ean present antigen (Ag) to T cells. Therefore, using a murine model of cutaneous leishmaniasis, we analyzed the ability of epidermal cells to induce a T eell response to L.major. The results demonstrated that freshly isolated LC, but not cuItured LC, are highly active in presenting L.major Ag in vitro to T cells from primed mice and to a L.major-specific T cell clone. Furthermore, freshly isolated LC had the ability to retain L.major Ag in immunogenic form for at least 2 days. Their efficiency was much greater than that of irradiated spleen cells, a standard population of APC. LC stimulated both T cell proliferation and production of the Iymphokines interleukin (IL)-2 and IL-4. The response was Ag specific and could be induced by lysate of L. major parasites and by live organisms. The data suggest that epidermal LC are important APC in eutaneous leishmaniasis. They may perform a critical funetion by eapturing L.major Ag in the skin and presenting it either to quiescent T eells circulating through the draining lymph node or locally to T effector cells infiltrating the cutaneous lesion.
KW  - Immunologie
Y1  - 1992
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45872
ER  - 
TY  - JOUR
A1  - Blank, Christine
A1  - Fuchs, Harald
A1  - Rappersberger, Klemens
A1  - Röllinghoff, Martin
A1  - Moll, Heidrun
T1  - Parasitism of epidermal Langerhans cells in experimental cutaneous leishmaniasis with Leishmania major
N2  - Murine epidermal Langerhans cells (LC) have been demonstrated to stimulate a vigorous T cell response to Leishmania major, a cause of human cutaneous leishmaniasis. It was therefore of interest to analyze whether LC can take up viable parasites. Epidermal cells were obtained from mouse ear skin for incubation with L. major and subsequent detection of intracellular parasites by cytochemistry. Freshly isolated LC, but not cultured LC, phagocytosed L. major and the uptake was inhibited by antibodies to the complement receptor type 3. Electron microscopic studies revealed the presence of viable amastigotes within Le. Moreover, with double-Iabeling techniques, L. major-containing LC could also be detected in infected skin. The results demonstrate that LC can internalize L. major. Since the number of organisms per infected LC remained consistently low, the prime task of LC may not be the promotion of parasite spreading but the presentation of L. major antigen to T cells and, thus, the regulation of the cellular immunity during cutaneous leishmaniasis.
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45850
ER  - 
TY  - JOUR
A1  - Pfeffer, K.
A1  - Schoel, H.
A1  - Gulle, H.
A1  - Moll, Heidrun
A1  - Kromer, S.
A1  - Kaufmann, S. H. E.
A1  - Wagner, H.
T1  - Analysis of primary T cell responses to intact and fractionated microbial pathogens
N2  - Freshly isolated human T lymphocytes were tested for their response to mycobacteria, mycobacteriallysates, 2 dimensional (2D) PAGE separated mycobacteriallysates, leishmania and defined leishmanial antigen preparations. While,o T cells proliferated vigourously in the presence of mycobacteria and mycobacteria derived lysates, a significant stimulation from 2 D gel separated lysates was not detected. In addition '10 T cells failed to respond towards leishmania or leishmanial components. In the ab T cell compartment some donors, presumably according to their state of immunity against mycobacteria, responded to mycobacteria, mycobacterial lysates and 2 D gel separated mycobacterial lysates. Neither freshly isolated '10 T cells nor ab T cells from naive donors did mount a significant immune response against leishmania.
Y1  - 1991
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-46916
ER  - 
TY  - JOUR
A1  - Heller, Dieter
A1  - Krüger, Hans-Peter
T1  - Analyse dreistufig zu beantwortender Fragebogenitems
N2  - In Fragebögen tauchen häufig ternäre Antwortmöglichkeiten auf (z.B. ja - nein - weiß nicht). Für eine Analyse solcher Hems werden Kennwerte vorgeschlagen. Dabei wird ein der Schwierigkeit analoger Popularitätsindex eingeführt, der in p+ den Anteil der Ja-Antworten angibt. Aus p+ und p-, dem Anteil der Nein-Antworten, wird ein Aktualitätsindex definiert, der in den Grenzen zwischen 0 und 1 variiert und die Eliminierung wenig aktueller Fragen gestattet. Zur Bestimmung der Trennschärfe werden Punkt-Vierfelder- oder phi-Koeffizienten angegeben. die aus der Zerlegung des X2 einer 3x2-Tafel in eine 2x2-Tafel und in eine auf die Unbestimmtheitsantwort zurückgehende Restkomponente entstehen. Ebenso werden Koeffizienten für Iteminterkorrelationen aus 3x3-Tafeln und Indizes für die Reliabilität angegeben.
N2  - In this paper the question is raised how to proceed in item-analysis if the answers may be given in three ways: "yes", "no" or "don't know". In defining and calculating parameters the following suggestions are made: define the difficulty index of an item as the proportion of the number of "yes" answers p+ within a random sampie of N Ss. Define an index of actuality as a function of p+ p- where p- is the proportion of the number of "no" answers such that min. f(p+p-) = 0 and max. f(p+p-) = 1 and eliminate items having low actuality indices. Define item-discriminating power (item-test correlation) by a point four-fold or phi coefficient determined by partitioning the chi square of a 3x2 contingency table into 2x2 contingency plus a residual due to "don't know" answers. In a similar way define item-intercorrelations on the basis of 3x3 contingency tables and reliability indices.
Y1  - 1976
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41583
ER  - 
TY  - JOUR
A1  - Krüger, Hans-Peter
A1  - Kohnen, Ralf
T1  - Eine neue Methode zur Prüfung der Wirkung von Psychopharmaka - Die "Weltbeschreibung"
N2  - Kompensation und das Problem der Zuggebbarkeit werden als die beiden wichtigsten Störquellen bei der Erfassung pharmakonbedingter Befindlichkeitsänderungen dargestellt. Gefördert werden diese Prozesse durch eine Zentrierung der Methode auf die Selbstbeobachtung. Es wird die Hypothese aufgestellt, daß die Selbstbeobachtung ersetzbar ist durch eine Beschreibung der "Welt draußen". Die Person kann sich nur in der Welt erleben - folglich werden Veränderungen dieses Erlebnis auch Veränderungen in der Beschreibung der Welt nach sich ziehen. Ausgehend von dieser Hypothese wird ein Experiment konzipiert, in dem die Vpn lediglich die experimentelle Situation und die am Experiment beteiligten anderen Vpn beschreiben, nicht aber sich selbst. Es kann gezeigt werden, daß mit den so gewonnenen Maßen eindeutige Wirkungen des eingesetzten Tranquilizers nachgewiesen werden können, ebenso eindeutige Dosis-Wirkungs-Beziehungen. Die Konsequenzen für eine pharmakopsychologische Methodik werden diskutiert. Zudem wird herausgehoben, daß Tranquilantien dann als positiv bewertet werden können, wenn sie die Reagibilität der Vpn auf die Situation erhöhen und durch eine Verringerung des allgemeinen Aktivierungsniveaus eine adäquate Verarbeitung angstinduzierender Situatonen ermöglichen.
N2  - Compensation and readiness to admit drug effects are described as the most important modifying factors in assessing changes of mood that is due to psychotropic drugs. Both processes are advanced by a methodology which focuses on the selfobservation of the experimental subjects. The authors propose the hypothesis that seifreports may be replaced by a description of the "outside world". The human being is only able to experience itself within its concrete world; consequently, changes of its experience entail changes of the description of the world. On the basis of this hypothesis an experiment is conceived in which the subjects describe only the experimental situation and the other participating subjects, not themselves, however. The authors hold that the parameters emerging from this approach give evidence both of clear-cut tranquilizer-effects and stable drug-dosage-relationships. Consequences for pharmaco-psychological methodology are discussed. The authors accentuate that tranquilizers can be seen as having positive effects if they help to enhance the subject's reagibility to the situation and, by reducing the general activation level, enable the subject to cope with anxiety inducing situations.
Y1  - 1980
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41566
ER  - 
TY  - JOUR
A1  - Krüger, Hans-Peter
A1  - Buchta, Herbert
T1  - Nichtparametrischer Vergleich von Testprofilen und Verlaufskurven bei unabhängigen Stichproben
N2  - Werden k Testwerte an zwei oder mehreren Stichproben von Pbn erhoben, stellt sich das Problem des Vergleichs von Testprofilen. Ähnliche Fragen treten auf, wenn statt k verschiedenen Testwerten ein Meßwert zu k Zeitpunkten an einem Pb erhoben wird. Zur Auswertung dieser Fragestellung wird ein Vorgehen nach dem WILCOXON-Rangsummentest vorgeschlagen, der es erlaubt (1) Unterschiede aller Art (2) Unterschiede in der Lage und (3) Unterschiede in der Form der Profile zu prüfen. Das Vorgehen wird an einem Beispiel aufgezeigt. Erweiterungen auf andere Fälle werden diskutiert.
N2  - If kotest scores are collected in two or more sampies of subjects the problem of a comparison of test-proftles arises. Similar problems can be observed in those cases in which instead of k-different test-scores a test result of k-times is ascertained from a subjecL For purposes of interpretation an approach (Wi1coxon rank sum test) is suggested allowing the examination 01 1) differences of all kind, 2) differences of location and 3) differences of the forms of profIles. This approach is demonstrated by means of an example. Possibilities of applieating this approach in other eases are discussed.
Y1  - 1980
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41513
ER  - 
TY  - JOUR
A1  - Bonte, Dries
A1  - Hovestadt, Thomas
A1  - Poethke, Hans-Joachim
T1  - Male-killing endosymbionts: influence of environmental conditions on persistance of host metapopulation
N2  - Background: Male killing endosymbionts manipulate their arthropod host reproduction by only allowing female embryos to develop into infected females and killing all male offspring. Because of the reproductive manipulation, we expect them to have an effect on the evolution of host dispersal rates. In addition, male killing endosymbionts are expected to approach fixation when fitness of infected individuals is larger than that of uninfected ones and when transmission from mother to offspring is nearly perfect. They then vanish as the host population crashes. High observed infection rates and among-population variation in natural systems can consequently not be explained if defense mechanisms are absent and when transmission efficiency is perfect. Results: By simulating the host-endosymbiont dynamics in an individual-based metapopulation model we show that male killing endosymbionts increase host dispersal rates. No fitness compensations were built into the model for male killing endosymbionts, but they spread as a group beneficial trait. Host and parasite populations face extinction under panmictic conditions, i.e. conditions that favor the evolution of high dispersal in hosts. On the other hand, deterministic 'curing' (only parasite goes extinct) can occur under conditions of low dispersal, e.g. under low environmental stochasticity and high dispersal mortality. However, high and stable infection rates can be maintained in metapopulations over a considerable spectrum of conditions favoring intermediate levels of dispersal in the host. Conclusion: Male killing endosymbionts without explicit fitness compensation spread as a group selected trait into a metapopulation. Emergent feedbacks through increased evolutionary stable dispersal rates provide an alternative explanation for both, the high male-killing endosymbiont infection rates and the high among-population variation in local infection rates reported for some natural systems.
KW  - Metapopulation
KW  - Parasit
KW  - Wirt
KW  - Endosymbiont
KW  - Theoretische Ökologie
KW  - Host-parasite interactions
KW  - individual-based model
Y1  - 2008
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45344
ER  - 
TY  - JOUR
A1  - Bonte, Dries
A1  - Hovestadt, Thomas
A1  - Poethke, Hans Joachim
T1  - Sex-specific dispersal and evolutionary rescue in metapopulations infected by male killing endosymbionts
N2  - Background: Male killing endosymbionts manipulate their arthropod host reproduction by only allowing female embryos to develop into infected females and killing all male offspring. Because the resulting change in sex ratio is expected to affect the evolution of sex-specific dispersal, we investigated under which environmental conditions strong sex-biased dispersal would emerge, and how this would affect host and endosymbiont metapopulation persistence. Results: We simulated host-endosymbiont metapopulation dynamics in an individual-based model, in which dispersal rates are allowed to evolve independently for the two sexes. Prominent male-biased dispersal emerges under conditions of low environmental stochasticity and high dispersal mortality. By applying a reshuffling algorithm, we show that kin-competition is a major driver of this evolutionary pattern because of the high within-population relatedness of males compared to those of females. Moreover, the evolution of sex-specific dispersal rescues metapopulations from extinction by (i) reducing endosymbiont fixation rates and (ii) by enhancing the extinction of endosymbionts within metapopulations that are characterized by low environmental stochasticity. Conclusion: Male killing endosymbionts induce the evolution of sex-specific dispersal, with prominent male-biased dispersal under conditions of low environmental stochasticity and high dispersal mortality. This male-biased dispersal emerges from stronger kin-competition in males compared to females and induces an evolutionary rescue mechanism.
KW  - Metapopulation
KW  - Theoretische Ökologie
KW  - Endosymbiont
KW  - Wirt
KW  - Parasit
KW  - Host-parasite interactions
KW  - individual-based model
Y1  - 2009
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45351
ER  - 
TY  - JOUR
A1  - Gros, Andreas
A1  - Hovestadt, Thomas
A1  - Poethke, Hans Joachim
T1  - Evolution of local adaptions in dispersal strategies
N2  - The optimal probability and distance of dispersal largely depend on the risk to end up in unsuitable habitat. This risk is highest close to the habitat’s edge and consequently, optimal dispersal probability and distance should decline towards the habitat’s border. This selection should lead to the emergence of spatial gradients in dispersal strategies. However, gene flow caused by dispersal itself is counteracting local adaptation. Using an individual based model we investigate the evolution of local adaptations of dispersal probability and distance within a single, circular, habitat patch. We compare evolved dispersal probabilities and distances for six different dispersal kernels (two negative exponential kernels, two skewed kernels, nearest neighbour dispersal and global dispersal) in patches of different size. For all kernels a positive correlation between patch size and dispersal probability emerges. However, a minimum patch size is necessary to allow for local adaptation of dispersal strategies within patches. Beyond this minimum patch area the difference in mean dispersal distance between center and edge increases linearly with patch radius, but the intensity of local adaptation depends on the dispersal kernel. Except for global and nearest neighbour dispersal, the evolved spatial pattern are qualitatively similar for both, mean dispersal probability and distance. We conclude, that inspite of the gene-flow originating from dispersal local adaptation of dispersal strategies is possible if a habitat is of sufficient size. This presumably holds for any realistic type of dispersal kernel.
KW  - Ausbreitung
KW  - Evolution
KW  - Computersimulation
KW  - Ökologie
KW  - nearest-neighbour dispersal
KW  - global dispersal
KW  - evolution
KW  - individual based simulation
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45406
ER  - 
TY  - JOUR
A1  - Obermaier, Elisabeth
A1  - Heisswolf, Annette
A1  - Randlkofer, B.
A1  - Meiners, T.
T1  - Enemies in low places - insects avoid winter mortality and egg parasitism by modulating oviposition height
N2  - Oviposition site selection in insects is essential in terms of low egg mortality, high offspring survival and therefore a high reproductive output. Although oviposition height could be a crucial factor for the fitness of overwintering eggs, it has rarely been investigated. In this study the oviposition height of a polyphagous leaf beetle, Galeruca tanaceti Linnaeus in different habitats and at different times of the season was examined and its effect on egg clutch mortality was recorded. The leaf beetle occurs as an occasional pest on several agricultural plants. It deposits its eggs within herbaceous vegetation in autumn. Eggs are exposed to numerous biotic and abiotic mortality factors summarized as egg parasitism and winter mortality. Oviposition height of the leaf beetle was not uniform, but changed significantly with the structure of the habitat and during the season. Mean oviposition height per site (70.2±4.9 cm) was significantly higher than mean vegetation height (28.4±2.4 cm). Height of plants with egg clutches attached and oviposition height were significantly positively correlated. The results suggest that females try to oviposit as high as possible in the vegetation and on the plants selected. In accordance with this, the probability of egg parasitism and of winter egg clutch mortality significantly declined with increasing oviposition height. A preference of G. tanaceti for oviposition sites high up in the vegetation might therefore have evolved due to selection pressures by parasitoids and winter mortality.
KW  - abiotic factors
KW  - Chrysomelidae
KW  - enemy free space
KW  - Galeruca tanaceti
KW  - oviposition site
KW  - plant-animal interactions
KW  - Oomyzus galerucivorus
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-48200
ER  - 
TY  - JOUR
A1  - Hovestadt, Thomas
A1  - Mitesser, Oliver
A1  - Elmes, Graham
A1  - Thomas, Jeremy A.
A1  - Hochberg, Michael E.
T1  - An Evolutionarily Stable Strategy model for the evolution of dimorphic development in the butterfly Maculinea rebeli, a social parasite of Myrmica Ant Colonies
N2  - Caterpillars of the butterfly Maculinea rebeli develop as parasites inside ant colonies. In intensively studied French populations, about 25% of caterpillars mature within 1 year (fast-developing larvae [FDL]) and the others after 2 years (slow-developing larvae [SDL]); all available evidence indicates that this ratio is under the control of egg-laying females. We present an analytical model to predict the evolutionarily stable fraction of FDL (pESS). The model accounts for added winter mortality of SDL, general and kin competition among caterpillars, a competitive advantage of SDL over newly entering FDL (priority effect), and the avoidance of renewed infection of ant nests by butterflies in the coming season (segregation). We come to the following conclusions: (1) all factors listed above can promote the evolution of delayed development; (2) kin competition and segregation stabilize pESS near 0.5; and (3) a priority effect is the only mechanism potentially selecting for. However, given the empirical data, pESS is predicted to fall closer to 0.5 than to the 0.25 that has been observed. In this particular system, bet hedging cannot explain why more than 50% of larvae postpone growth. Presumably, other fitness benefits for SDL, for example, higher fertility or longevity, also contribute to the evolution of delayed development. The model presented here may be of general applicability for systems where maturing individuals compete in small subgroups.
KW  - delayed development
KW  - growth dimorphism
KW  - evolutionarily stable strategy (ESS)
KW  - ant-butterfly interaction
KW  - social parasitism
Y1  - 2007
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-48165
ER  - 
TY  - JOUR
A1  - Poethke, Hans J.
A1  - Pfenning, Brenda
A1  - Hovestadt, Thomas
T1  - The relative contribution of individual and kin selection to the evolution of density-dependent dispersal rates
N2  - Questions: What are the relative contributions of kin selection and individual selection to the evolution of dispersal rates in fragmented landscapes? How do environmental parameters influence the relative contributions of both evolutionary forces? Features of the model: Individual-based simulation model of a metapopulation. Logistic local growth dynamics and density-dependent dispersal. An optional shuffling algorithm allows the continuous destruction of any genetic structure in the metapopulation. Ranges of key variables: Depending on dispersal mortality (0.05-0.4) and the strength of environmental fluctuations, mean dispersal probability varied between 0.05 and 0.5. Conclusions: For local population sizes of 100 individuals, kin selection alone could account for dispersal probabilities of up to 0.1. It may result in a ten-fold increase of optimal dispersal rates compared with those predicted on the basis of individual selection alone. Such a substantial contribution of kin selection to dispersal is restricted to cases where the overall dispersal probabilities are small (textless 0.1). In the latter case, as much as 30% of the total fitness of dispersing individuals could arise from the increased reproduction of kin left in the natal patch.
KW  - dispersal rate
KW  - dynamics
KW  - environmental correlation
KW  - evolutionary modelling
KW  - genetics
KW  - individual-based model
KW  - kin competition
Y1  - 2007
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-48225
ER  - 
TY  - JOUR
A1  - Hovestadt, Thomas
A1  - Poethke, Hans J.
A1  - Messner, Stefan
T1  - Variability in dispersal distances generates typical successional patterns: a simple simulation model
N2  - More recently, it became clear that conclusions drawn from traditional ecological theory may be altered substantially if the spatial dimension of species interactions is considered explicitly. Regardless of the details of these models, spatially explicit simulations of ecological processes have nearly universally shown that spatial or spatio-temporal patterns in species distributions can emerge even from homogeneous starting conditions; limited dispersal is one of the key factors responsible for the development of such aggregated and patchy distributions (cf., Pacala 1986, Holmes et al. 1994, Molofsky 1994, Tilman 1994, Bascompte and Sole 1995, 1997, 1998, Jeltsch et al. 1999). In line with these ideas, we wish to draw attention to the fact that in heterogeneous landscapes differences in characteristic dispersal distances between species are a sufficient precondition for the emergence of a successional pattern. We will use a simple, spatially explicit simulation program to demonstrate the validity of this statement. We will also show that the speed of the successional progress depends on scale and heterogeneity in the distribution of suitable habitat.
KW  - community
KW  - competition
KW  - environments
KW  - habitats
KW  - life-history
Y1  - 2000
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-48178
ER  - 
TY  - JOUR
A1  - Bach, Ulrich
T1  - Oral rhetoric in writings for a mixed literate and illiterate audience
N2  - No abstract available
Y1  - 1989
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47124
ER  - 
TY  - JOUR
A1  - Krüger, H.-P.
T1  - Psychologische Charakteristika der "Düker-Aufgabe" oder "Was ist die Leistung an der Leistung?"
N2  - In den Experimenten H. Dükers haben die Vpn regelhaft sehr viele sehr einfache hochgeübte Tätigkeiten auszuführen. Wird dies durch das Einführen von Zusatzaufgaben kompliziert, kann eine Steigerung der Leistung resultieren (erklärt etwa durch "Reaktive Anspannungssteigerung") oder eine Minderung (wie für das "Unterschwellige Wollen" gezeigt). Eine nähere Analyse der Düker-Aufgabe zeigt, daß die Variable "Arbeitsrhythmus" für diesen Unterschied verantwortlich ist. Wird dieser Rhythmus über eine externe Quelle gegeben oder kann eine Zusatzaufgabe in den vorhandenen Rhythmus integriert werden, resultiert eine Verbesserung. Treten zwei inkompatible Rhythmen in einer Situation auf, resultiert ein drastischer Leistungseinbruch. Diese Systematik wird am pharmakopsychologischen Beispiel einer Statistik über Verkehrsunfälle unter Alkoholeinfluß diskutiert.
N2  - The experiments of H. Düker are characterized by subjects who had to work a great amount of very simple, highly exercised tasks. If this work is omplicated by an additional task, the paradigm "Reaktive Anspannungssteigerung" (reactive strengthening of psychic strain) describes an improvement in performance, the paradigm of "Unterschwelliges Wollen" (unperceptible willing) a decrease. An analysis ofthe experimental situation reveals the "rhythm of working" as the main variable responsible for this difference. If this rhythm is given by an external source or if an additional task can be integrated in an existing rhythm, an improvement results. Two incompatible rhythms in one situation lead to a dramatic decrease in performance. To give a pharmacopsychological example this taxonomy is discussed using statistics about the effect of alcohol on traffic accident rates.
KW  - Heinrich Düker (1898-1986)
KW  - Aktivierung
KW  - Motivation
KW  - Rhythmus
KW  - Alkohol
KW  - Straßenverkehr
KW  - Heinrich Düker (1898-1986)
KW  - activation
KW  - motivation
KW  - rhythm
KW  - alcohol
KW  - driving while intoxicated
Y1  - 1988
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41460
ER  - 
TY  - JOUR
A1  - Christl, Manfred
A1  - Krimm, Stefan
A1  - Kraft, Arno
T1  - Einige Valene von benzanellierten fünfgliedrigen Heteroarenen - Synthesen und NMR-Spektren
N2  - No abstract available
Y1  - 1990
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31559
ER  - 
TY  - JOUR
A1  - Fackler, Guido
T1  - Musik in Konzentrations- und Vernichtungslagern
N2  - No abstract available
KW  - Musik
KW  - Konzentrationslager
Y1  - 1991
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41814
ER  - 
TY  - JOUR
A1  - Mahsberg, Dieter
T1  - Contact chemoreception of prey in hunting scorpions
N2  - Scorpions commonly are assumed to hunt on living prey. But under laboratory conditions they also respond very sensitively to dead insects lying on the substrate. In many cases the motionless prey is seized and consumed. It was investigated how this behavior can be elicited. The buthid scorpions Androctonus australis (L.) and Buthus occitanus (Am.) not only find motionless prey again which was stung but managed to escape before dying: They also respond to extracts of the cuticle of prey insects. After touching prey marks' either with the tips of the chelae fingers or the tarsi of the walking legs or the pectine organs specific responses (searching, seizing, feeding) are released at a high rate. Behavioral experiments demonstrate for the first time the chemosensitivity of the pectine organs for which only mechanosensitivity had been proofed formerly. Mechanical as well as contact chemical stimulation of these organs cause scorpions to orient towards the stimulus source which is grasped, retained and consumed or rejected depending on its quality. The probably responsible chemosensitive receptors are already described in the literature. The possible adaptive value and the biological significance of contact chemoreception in prey catching and in other aspects of the life of scorpions is discussed.
KW  - Skorpion
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45784
ER  - 
TY  - JOUR
A1  - Kaupp, Martin
A1  - Stoll, H.
A1  - Preuss, H.
T1  - Pseudopotential Calculations for Methyl Compounds of Zinc and Magnesium
N2  - Pseudopotentials and valence basis sets to be used in calculations for organometallic compounds of zinc and magnesium have been tested in calculations for the M(CH\(_3\))\(_n\) (M = Zn, Mg; n = 1,2) molecules. Valence correlation effects are treated at the SDCI and CEPA levels. The capability of a polarization potential on zinc to account for the valence shell contracting effect of core valence correlation is studied. Properties considered are geometries, force constants, Mulliken populations, ionization potentials, atomization, and binding energies. Differences in bonding between the two dimethyl compounds are discussed.
KW  - Zink
KW  - Magnesium
Y1  - 1990
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-46194
ER  - 
TY  - JOUR
A1  - Krüger, Hans-Peter
T1  - Nähe und Distanz in sozialen Beziehungen und ihre quantitative Erfassung
N2  - Es wird ein neues soziometrisches Verfahren vorgeschlagen, das in seiner Grundlegung von heute üblichen Wahlverfahren abweicht. Dabei wird versucht, in einem ersten Teil die Gedanken darzustellen, die zur Formulierung der soziometrischen Fragen geführt haben. Im zweiten Teil wird der Gang der Auswertung dargestellt, der ein differenziertes Bild der untersuchten Personen zeichnen soll. Im Teil "Ergebnisse" wird am Beispiel von Extremgruppen gezeigt, was die Methode leisten kann. Schließlich werden noch mögliche Modifikationen des Verfahrens aufgezeigt.
Y1  - 1976
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41446
ER  - 
TY  - JOUR
A1  - Marohn, Frank
T1  - Global sufficiency of extreme order statistics in location models of Weibull type
N2  - In Janssen and Reiss (1988) it was shown that in a location model of a Weibull type sample with shape parameter -1 < a < 1 the k(n) lower extremes are asymptotically local sufficient. In the present paper we show that even global sufficiency holds. Moreover, it turns out that convergence of the given statistical experiments in the deficiency metric does not only hold for compact parameter sets but for the whole real line.
KW  - Extremwertstatistik
KW  - Weibull-Verteilung
Y1  - 1991
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47874
ER  - 
TY  - JOUR
A1  - Berger, Susanne
A1  - Ellersiek, Ulrike
A1  - Westhoff, Peter
A1  - Steinmüller, Klaus
T1  - Studies on the expression of NDH-H, a subunit of the NAD(P)H-plastoquinone-oxidoreductase of higher-plant chloroplasts
N2  - The plastid genomes of higher plants contain eleven reading frames (ndhA-K) that are homologous to genes encoding subunits of the mitochondrial NADH-ubiquinone-oxidoreductase (complex I). The carboxyterminal end of the NDH-H subunit from rice (Oryza sativa L.) was expressed as a fusion protein in Escherichia coli and antibodies against the fusion protein were generated in rabbits. The antibody was used to study the expression of NDH-H, and the following results were obtained: (i) NDH-H is expressed in mono- and dicotyledonous plants, (ii) NDH-H is localized on the stroma lamellae of the thylakoid membrane and (iii) NDH-H is expressed in etioplasts. Together with the finding that two other ndh genes (ndhI and ndhK) are expressed in plastids, these results point to the existence of an NAD(P)H-plastoquinone-oxidoreductase on the thylakoid membrane. The possible function of the enzyme in plastids is discussed and it is suggested that it works in balancing the ATP/ADP and the NADPH/NADP ratios during changing external (i.e. light) or internal (i.e. ATP and NADPH demands of biosynthetic pathways of the plastid) conditions.
KW  - NAD(P)H-plastoquinone-oxidoreductase
KW  - ndhH gene
KW  - Plastid DNA
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31283
ER  - 
TY  - JOUR
A1  - Berger, Susanne
A1  - Ellersiek, Ulrike
A1  - Kinzelt, Dagmar
A1  - Steinmüller, Klaus
T1  - Immunopurification of a subcomplex of the NAD(P)H-plastoquinone-oxidoreductase from the cyanobacterium Synechocystis sp. PCC6803
N2  - An antibody against the NDH-K subunit of the NAD(P)H-dehydrogenase from the cyanobacterium Synechocystis sp. PCC6803 was used to isolate a subcomplex ofthe enzyme from Triton X-lOO solubilized total membranes by immunoaffinity chromatography. The isolated subcomplex consisted of seven major polypeptides with molecular masses of 43, 27, 24, 21, 18, 14 and 7 kDa. The amino-terminal amino acid sequences of the polypeptides were determined. By comparing the sequences with the amino acid sequences deduced from DNA. three proteins were identified as NDH-H (43 kDa). NDH-K (27 kDa) and NDH-J (24 kDa). A fourth subunit (NDH-J, 21 kDa) was identified by Western blot analysis with an NDH-J antibody.
KW  - NAD(P)H-dehydrogenase
KW  - Cyanobacteria
KW  - Synechocystis sp. PCC6803
KW  - NDH-H
KW  - NDH-I
KW  - NDH-J
KW  - NDH-K
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31249
ER  - 
TY  - JOUR
A1  - Berger, Susanne
A1  - Ellersiek, Ulrike
A1  - Steinmüller, Klaus
T1  - Cyanobacteria contain a mitochrondrial complex I-homologous NADH-dehydrogenase
N2  - Thylakoid and cytoplasmic membranes of the cyanobacterium Syncchocystis sp. PCC 6803 were purified by sucrose gradient centrifugation. Both membranes oxidize NADH in a rotenone-sensitive reaction. Antibodies prepared against psbG/ndhKand ndhJ fusion proteins detect the corresponding polypeptides in both membrane preparations. This demonstrates that a NADH-dehydrogenase, homologous to the mitochondrial NADHubiquinone-oxidoreductase (complex I of the respiratory chain) is present in cyanobacteria, The NADH-dehydrogenase can be solubilized with the detergent /-D-dodecylmaltoside. Sedimentation analysis of the solubilized enzyme on a sucrose gradient indicates that it is a multisubunit protein complex.
KW  - Respiratory chain
KW  - NADH-dehydrogenase
KW  - Cyanobacteria
KW  - Synechocystis 6803
Y1  - 1991
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31223
ER  - 
TY  - JOUR
A1  - Mitesser, Oliver
A1  - Weissel, Norbert
A1  - Strohm, Erhard
A1  - Poethke, Hans-Joachim
T1  - Adaptive dynamic resource allocation in annual eusocial insects: Environmental variation will not necessarily promote graded control
N2  - Background: According to the classical model of Macevicz and Oster, annual eusocial insects should show a clear dichotomous "bang-bang" strategy of resource allocation; colony fitness is maximised when a period of pure colony growth (exclusive production of workers) is followed by a single reproductive period characterised by the exclusive production of sexuals. However, in several species graded investment strategies with a simultaneous production of workers and sexuals have been observed. Such deviations from the "bang-bang" strategy are usually interpreted as an adaptive (bet-hedging) response to environmental fluctuations such as variation in season length or food availability. To generate predictions about the optimal investment pattern of insect colonies in fluctuating environments, we slightly modified Macevicz and Oster's classical model of annual colony dynamics and used a dynamic programming approach nested into a recurrence procedure for the solution of the stochastic optimal control problem. Results: 1) The optimal switching time between pure colony growth and the exclusive production of sexuals decreases with increasing environmental variance. 2) Yet, for reasonable levels of environmental fluctuations no deviation from the typical bang-bang strategy is predicted. 3) Model calculations for the halictid bee Lasioglossum malachurum reveal that bet-hedging is not likely to be the reason for the graded allocation into sexuals versus workers observed in this species. 4) When environmental variance reaches a critical level our model predicts an abrupt change from dichotomous behaviour to graded allocation strategies, but the transition between colony growth and production of sexuals is not necessarily monotonic. Both, the critical level of environmental variance as well as the characteristic pattern of resource allocation strongly depend on the type of function used to describe environmental fluctuations. Conclusion: Up to now bet-hedging as an evolutionary response to variation in season length has been the main argument to explain field observations of graded resource allocation in annual eusocial insect species. However, our model shows that the effect of moderate fluctuations of environmental conditions does not select for deviation from the classical bang-bang strategy and that the evolution of graded allocation strategies can be triggered only by extreme fluctuations. Detailed quantitative observations on resource allocation in eusocial insects are needed to analyse the relevance of alternative explanations, e.g. logistic colony growth or reproductive conflict between queen and workers, for the evolution of graded allocation strategies.
KW  - Insekten
KW  - Fitness
KW  - Evolution
KW  - Sozialität
KW  - resource allocation
KW  - fitness
KW  - evolution
KW  - eusociality
KW  - insect
Y1  - 2007
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45412
ER  - 
TY  - JOUR
A1  - Mitesser, Oliver
A1  - Weissel, Norbert
A1  - Strohm, Erhard
A1  - Poethke, Hans J.
T1  - The evolution of activity breaks in the nest cycle of annual eusocial bees: A simple model of delayed exponential growth
N2  - Abstract: Background Social insects show considerable variability not only in social organisation but also in the temporal pattern of nest cycles. In annual eusocial sweat bees, nest cycles typically consist of a sequence of distinct phases of activity (queen or workers collect food, construct, and provision brood cells) and inactivity (nest is closed). Since the flight season is limited to the time of the year with sufficiently high temperatures and resource availability, every break reduces the potential for foraging and, thus, the productivity of a colony. This apparent waste of time has not gained much attention. Results We present a model that explains the evolution of activity breaks by assuming differential mortality during active and inactive phases and a limited rate of development of larvae, both reasonable assumptions. The model predicts a systematic temporal structure of breaks at certain times in the season which increase the fitness of a colony. The predicted pattern of these breaks is in excellent accordance with field data on the nest cycle of the halictid Lasioglossum malachurum. Conclusion Activity breaks are a counter-intuitive outcome of varying mortality rates that maximise the reproductive output of primitively eusocial nests.
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-48196
ER  - 
TY  - JOUR
A1  - Poethke, Hans J. ;
A1  - Liebig, Jürgen
T1  - Risk-sensitive foraging and the evolution of cooperative breeding and reproductive skew
N2  - Abstract: Background Group formation and food sharing in animals may reduce variance in resource supply to breeding individuals. For some species it has thus been interpreted as a mechanism of risk avoidance. However, in many groups reproduction is extremely skewed. In such groups resources are not shared equally among the members and inter-individual variance in resource supply may be extreme. The potential consequences of this aspect of group living have not attained much attention in the context of risk sensitive foraging. Results We develop a model of individually foraging animals that share resources for reproduction. The model allows analyzing how mean foraging success, inter-individual variance of foraging success, and the cost of reproduction and offspring raising influence the benefit of group formation and resource sharing. Our model shows that the effects are diametrically opposed in egalitarian groups versus groups with high reproductive skew. For individuals in egalitarian groups the relative benefit of group formation increases under conditions of increasing variance in foraging success and decreasing cost of reproduction. On the other hand individuals in groups with high skew will profit from group formation under conditions of decreasing variance in individual foraging success and increasing cost of reproduction. Conclusion The model clearly demonstrates that reproductive skew qualitatively changes the influence of food sharing on the reproductive output of groups. It shows that the individual benefits of variance reduction in egalitarian groups and variance enhancement in groups with reproductive skew depend critically on ecological and life-history parameters. Our model of risk-sensitive foraging thus allows comparing animal societies as different as spiders and birds in a single framework.
Y1  - 2008
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-48214
ER  - 
TY  - JOUR
A1  - Bonte, Dries
A1  - Hovestadt, Thomas
A1  - Poethke, Hans-Joachim
T1  - Evolution of dispersal polymorphism and local adaptation of dispersal distance in spatially structured landscapes
N2  - Many organisms show polymorphism in dispersal distance strategies. This variation is particularly ecological relevant if it encompasses a functional separation of short- (SDD) and long-distance dispersal (LDD). It remains, however, an open question whether both parts of the dispersal kernel are similarly affected by landscape related selection pressures. We implemented an individual-based model to analyze the evolution of dispersal traits in fractal landscapes that vary in the proportion of habitat and its spatial configuration. Individuals are parthenogenetic with dispersal distance determined by two alleles on each individual‘s genome: one allele coding for the probability of global dispersal and one allele coding for the variance of a Gaussian local dispersal with mean value zero. Simulations show that mean distances of local dispersal and the probability of global dispersal, increase with increasing habitat availability, but that changes in the habitat's spatial autocorrelation impose opposing selective pressure: local dispersal distances decrease and global dispersal probabilities increase with decreasing spatial autocorrelation of the available habitat. Local adaptation of local dispersal distance emerges in landscapes with less than 70% of clumped habitat. These results demonstrate that long and short distance dispersal evolve separately according to different properties of the landscape. The landscape structure may consequently largely affect the evolution of dispersal distance strategies and the level of dispersal polymorphism.
Y1  - 2009
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47856
ER  - 
TY  - JOUR
A1  - Krüger, Hans-Peter
A1  - Kohnen, Ralf
T1  - Wirkungen von Psychopharmaka auf das Lärmerleben
N2  - In allgemeinpsychologischen Lärmexperimenten ist eine monotone Beziehung zwischen physikalischer Lautstärke und erlebter Lautheit bestens abgesichert. In der vorliegenden Arbeit wird gezeigt, daß diese Beziehung unter Medikationsbedingungen nicht gilt. In einem 3 X 3 X 2-faktoriellen Versuchsplan mit den Faktoren physikalische Lautstärke (weißes Rauschen in 76, 79 und 82 dB), Medikation (Tranquilizer, Plazebo, Stimulizer) und (niedere bzw. hohe) Ansprechbarkeit auf Medikamente beurteilten insgesamt 54 junge weibliche Versuchspersonen in sechs Durchgängen eine Serie von 12 gleichabständigen Lärmstufen von 58 bis 92 dB in bezug auf die erlebte Lautheit. Es war weder eine Hauptwirkung Physikalische Lautstärke noch Medikation aufgetreten, dafür differenzierte die Schichtungsvariable Ansprechbarkeit auf beiden Faktoren. Eine Interpretation der Ergebnisse sensu Eysencks Drogenpostulat und im Sinne einer Aktivierungstheorie wird vorgenommen. Als Konsequenz für pharmakopsychologisches Experimentieren wird die Forderung erhoben, die in das Experiment eingebrachten Unabhängigen Variablen in ihrer Wirkung auf das Erleben der Vpn zu kontrollieren (subjektive Repräsentation des experimentellen Angebotes).
N2  - 54 young female subjects were required to report the experienced loudness of aseries of 12 white noises of 58 to 92 db, after having taken a tranquillizer, a placebo, or a stimulant, in a room with a white noise of 76, 79, or 82 db, respectively. The subjects were divided into two groups according to their sensitivity to drugs. The subjects being sensitive to drugs, expeiienced the loudness of the whole series of white noises, after having taken the tranquillizer, or in the room with a white noise of 76 or 79 db, respectively, as "high", and after having taken the stimulant, or in the room with a white noise of 82 db, as "low". On the contrary, the subjects being not sensitive to drugs, experienced the loudness of the whole series of white noises, after having taken the stimulant, or in the room with a white noise of 82 db, as "high", and after having taken the tranquillizer, or in the room with a white noise of 76 or 79 db, respectively, as "low". The results were discussed in the light of Eysenck's theory of drugeffects and of an activation theory. The results show the necessity of controlling the experienced intensity of loudness in pharmaco-psychological experiments.
Y1  - 1980
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41305
SN  - 0044-2712
ER  - 
TY  - JOUR
A1  - Krüger, Hans-Peter
A1  - Kohnen, Ralf
T1  - Tranquillizer effects in an experimental analog of group psychotherapy
N2  - In an experimental analog of verbal examinations, the call-up situation, the effects of two dosages of a tranquillizing agent (lopirazepam) are compared to placebo treatment. 72 male and female, healthy, young volunteers have been randomly assigned to 12 groups of 6 subjects each. Pulse frequency and performance were registered. The results indicated differential drug effects which were interpreted according to the hypotheses of "differential effects of social stressors". If a situation was highly challenging for a subject, the application of a tranquillizer in an adequately high dosage enabled him to perform well in spite of or because of strong increases in pulse frequency.
KW  - Tranquillizer
KW  - Social stress situations
KW  - Group dynamics
KW  - Healthy subjects
KW  - Differential effects of stressors
KW  - Anxiolysis
KW  - Telemetry Activation
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41316
ER  - 
TY  - JOUR
A1  - Ferner, U.,
A1  - Krüger, Hans-Peter
A1  - Lehmacher, W.
A1  - Rausche, A.
T1  - Auswertung von Verlaufsdaten: Anwendungsorientierte Darstellung anhand von Beispielen aus Pharmakologie und Psychiatrie
N2  - No abstract available
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41208
ER  - 
TY  - JOUR
A1  - Krüger, H.-P.
A1  - Bonerad, E. M.
A1  - Dennler, H. J.
A1  - Dunkl, E.
A1  - Friese, H. J.
A1  - Hain, C.
A1  - Kazenwadel, J.
A1  - Kohnen, Ralf
A1  - Maier, W.
A1  - Menzel, M.
T1  - Speech chronemics in drug evaluation
N2  - No abstract available
Y1  - 1992
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41213
ER  - 
TY  - JOUR
A1  - Hommers, Wilfried
A1  - Endres, Johann
T1  - Zur Wirkung der Entschuldigung auf verbundene Urteile von Strafe und Schadensersatz
N2  - Mit einem besonderen multivariaten Urteilsverbund von Ersatz und Strafe als abhängige Variable wurden die Wirkungen von Entschuldigung und Verschulden untersucht. 62 erwachsene Pbn beurteilten in zehn Geschichten über eine Briefmarkenruinierung die angemessene Strafe für den Schädiger und verbunden damit dessen angemessene Ersatzleistung an den Geschädigten und anschließend in vierzehn Geschichten über eine Körperverletzung beim Fußballspielen zusätzlich zu Strafe und Ersatz auch das angemessene Schmerzensgeld. In bei den Szenarien ergab sich, daß die Entschuldigung auf das Ersatz-Urteil zwar weniger stark als auf die Strafe wirkte, daß sie aber einen deutlichen Effekt auf das Ersatz-Urteil besaß. Weiterhin wurden die Verschuldensstufen auf beiden Skalen mit anderen relativen Distanzen beurteilt. Die Schmerzensgeld-Urteile im Fußball- Szenario ähnelten weitgehend den Strafe-Urteilen. Auch die Verteilungsformen der Urteile belegten die unterschiedlichen Verwendungsweisen der Teile des Urteilsverbunds. Die untersuchten Urteile scheinen daher zugleich restitutive und punitive Strukturen aufzuweisen, zu deren quantitativer Erfassung Forschungsansätze nötig sind, die den hier eingeführten Duplex-Verbund von Strafe und Ersatz beinhalten.
N2  - The effects of apology on the special multivariate duplex response of punishment and liability were examined. Sixty-two adult subjects rated the adequate amounts of restitution and punishment in ten stories about ruined stamps, and the just amounts judged in addition to restitution and punishment of in 14 stories about physical injury during a soccer game. In both scenarios apology had significant effects not only on punishment judgments, but also - though to a lesser degree - on recompensation. Different levels of responsibility were judged in differing patterns on both response types, with judgments of compensation in the soccer scenario appearing quite similar to those of punishment. Differences in the use of both responses were also revealed in the frequency distributions of the judgments. Since the judgments appeared to consist of two simultaneously existing structures, punishment and recompense, the use of the multivariate duplex response may be recommendable for further quantitative research on the moral cognitions.
KW  - Angewandte Psychologie / Zeitschrift / Experimentelle Psychologie
Y1  - 1989
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-44118
ER  - 
TY  - JOUR
A1  - Hommers, Wilfried
T1  - Ist das Konzept des Anti-Typus entbehrlich? Eine Antwort des Mischverteilungsansatzes zu einem IPC-Anti-Typ : (Prof. Dr. Dr. G.A. Lienert zum 70. Geburtstag)
N2  - Durch multidimensional skalierte Strukturen von Persönlichkeitsprofilen wurde eine AlternativHypothese für konfigurationsfrequenzanalytisch erlangte Konfigurationen begründet. Diese Alternativ- Hypothese besagte, daß die Anti-Typus-Konfigurationen eines dreivariaten 2x2x2- Datenvektors, aber auch die Neutral-Konfigurationen lediglich Folgen der Mischverteilung der Antworten zweier latenter, den Typen-Konfigurationen zuzuordnenden Klassen darstellen. Diese Hypothese wird an einem Datensatz zur Verteilung dichotomisierter Kontrollüberzeugungen geprüft und bestätigt. Das dabei konzipierte Konfigurale Fehlermodell (KFM) wird generell zur Ergänzung von Konfigurationsfrequenzanalysen (KFA) vorgeschlagen.
N2  - The hypothesis based on the MDS-structure of related personality profiles was that the anti-typeconfigurations of a three-variate 2x2x2-data-vector as well as the statistically neutral configurations are merely consequences of the combined distributions of the responses resulting from two latent classes related to the types found in the data-vector by configural frequency analysis. This hypothesis was confirmed with a data set originating from dichotomized distributions of a three-variate measure of generalized locus of control. The conceptualized configural error model (CEM) is proposed as a general supplement to configural frequency analysis (CFA).
KW  - Klinische Psychologie / Zeitschrift /Psychiatrie / Zeitschrift / Klinische Psychiatrie / Psychotherapie
Y1  - 1991
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-44109
ER  - 
TY  - JOUR
A1  - Hommers, Wilfried
T1  - Entschuldigung, Drittentschädigung und Schadenshöhe als Einflußgrößen des Urteils von Kindern und Erwachsenen
N2  - Kinder aus 3 Altersgruppen und Erwachsene beurteilten die verdiente Strafe für in Geschichten dargestellte Sachschäden, die aus Versehen oder aus Wut erfolgten. In den Geschichten wurde die Schadenshöhe variiert und außerdem, ob sich der Täter entschuldigte oder nicht bzw. ob der Geschädigte von einem Dritten eine Entschädigung erhielt oder nicht. Entschuldigung und Schadenshöhe hatten altersstabile Wirkungen, Entschuldigung etwa zweimal so stark wie die Schadenshöhe. Entschuldigung und Drittentschädigung hatten etwa gleichgroße Wirkungen, außer bei den Erwachsenen, bei denen die Wirkung der Drittentschädigung etwa auf die Stärke der Schadenswirkung abnahm. Der ursprüngliche Schaden war auch bei erfolgter Entschädigung, wenngleich schwächer, wirksam. Die Wirkungen der Ersatzleistung durch den Täter auf Strafurteile waren jedoch nicht völlig durch die Wirkungen von Entschuldigung und Entschädigung, erklärbar.
N2  - Children of three age groups and adults rated the deserved punishment for vignettes describing property damages done inadvertantly or in anger. The amount of damage varied in the stories as weIl as whether the harmdoer apologized or whether someone else compensated the harm. The effect of apology and amount of damage were unrelated to age. Apology reduced the punishment twice as much as amount of damage. The effect of third-party compensation was the same as that of apology, but was reduced in adults to around the amount of damage. Even after compensation of the damage, the prior amount of damage was still - though to a lesser degree - relevant for the punishment judgments. However, the total explanation of the effects of the harmdoer's restitution by apology and third-party compensation was not possible.
KW  - Angewandte Psychologie / Zeitschrift / Experimentelle Psychologie
Y1  - 1990
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-44095
ER  - 
TY  - JOUR
A1  - Hommers, Wilfried
A1  - Steller, Max
A1  - Zienert, Hans Joachim
T1  - Psychologische Entlassungsvorbereitung bei jugendlichen Strafgefangenen - Forschungsprogramm eines Vollzugsversuchs
N2  - No abstract available
KW  - Kriminologie / Strafrecht / Zeitschrift / Strafrechtsreform
Y1  - 1976
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-44079
ER  - 
TY  - JOUR
A1  - Maschwitz, Ulrich
A1  - Fiala, Brigitte
A1  - Linsenmair, Karl Eduard
T1  - Clerodendrum fistulosum (Verbenanceae), an unspecific myrmecophyte from Borneo with spontaneously opening domatia
N2  - Clerodendrumjistulosum Becc. is a true myrmecophyte as it offers nesting space for ants in hollow intemodes. In contrast to previous reports our investigations proved that these domatia open by themselves, thus providing cavities for a variety of different ant species. In Sarawak, Malaysia, we did not find an obligate relationship between C. jistulosum and a specific ant-partner. For comparison, studies on herbarium material of other Clerodendrum species were carried out a further species, C. deflexum from the Malay Peninsula and Sumatra presumably also is myrmecophytic.
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31013
ER  - 
TY  - JOUR
A1  - Weising, K.
A1  - Fiala, Brigitte
A1  - Ramloch, K.
A1  - Kahl, K.
A1  - Epplen, J. T.
T1  - Olingonucleotide fingerprinting in angiosperms
N2  - No abstract available
Y1  - 1990
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42884
ER  - 
TY  - JOUR
A1  - Marohn, Frank
T1  - Asymptotic sufficiency of order statistics for almost regular Weibull type densities
N2  - Consider a location family which is defined via a Weibull type density having shape parameter a = 1. We treat the problem, which portion of the order statistics is asymptotically sufficient. It turns out that the intermediate order statistics are relevant.
KW  - Weibull type density
KW  - intermediate order statistics
KW  - asymptotic sufficiency
KW  - local asymptotic normality
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45837
ER  - 
TY  - JOUR
A1  - Falk, Michael
A1  - Marohn, Frank
T1  - Asymptotically optimal tests for conditional distributions
N2  - No abstract available
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45823
ER  - 
TY  - JOUR
A1  - Janssen, A.
A1  - Marohn, Frank
T1  - On statistical information of extreme order statistics, local extreme value alternatives, and Poisson point processes
N2  - The aim of the present paper is to clarify the role of extreme order statistics in general statistical models. This is done within the general setup of statistical experiments in LeCam's sense. Under the assumption of monotone likelihood ratios, we prove that a sequence of experiments is asymptotically Gaussian if, and only if, a fixed number of extremes asymptotically does not contain any information. In other words: A fixed number of extremes asymptotically contains information iff the Poisson part of the limit experiment is non-trivial. Suggested by this result, we propose a new extreme value model given by local alternatives. The local structure is described by introducing the space of extreme value tangents. It turns out that under local alternatives a new class of extreme value distributions appears as limit distributions. Moreover, explicit representations of the Poisson limit experiments via Poisson point processes are found. As a concrete example nonparametric tests for Frechet type distributions against stochastically larger alternatives are treated. We find asymptotically optimal tests within certain threshold models.
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45816
ER  - 
TY  - JOUR
A1  - Falk, Michael
A1  - Marohn, Frank
T1  - Von Mises condition revisited
N2  - It is shown that the rate of convergence in the von Mises conditions of extreme value theory determines the distance of the underlying distribution function F from a generalized Pareto distribution. The distance is measured in terms of the pertaining densities with the limit being ultimately attained if and only if F is ultimately a generalized Pareto distribution. Consequently, the rate of convergence of the extremes in an lid sample, whether in terms of the distribution of the largest order statistics or of corresponding empirical truncated point processes, is determined by the rate of convergence in the von Mises condition. We prove that the converse is also true.
KW  - Von Mises conditions
KW  - extreme value theory
KW  - extreme value distribution
KW  - extreme order statistics
KW  - generalized Pareto distribution
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45790
ER  - 
TY  - JOUR
A1  - Fiala, Brigitte
A1  - Maschwitz, Ulrich
A1  - Pong, Tho, Yow
A1  - Helbig, Andreas J.
T1  - Studies of a South East Asian ant-plant association : protection of Macaranga trees by Crematogaster borneensis
N2  - In the humid tropics of SE Asia there are some 14 myrmecophytic species of the pioneer tree genus Macaranga (Euphorbiaceae). In Peninsular Malaysia a close association exists between the trees and the small, non-stinging myrmicine Crema togas ter borneensis. These ants feed mainly on food bodies provided by the plants and have their colonies inside the hollow intemodes. In a ten months field study we were able to demonstrate for four Macaranga species (M. triloba, M. hypoleuca, M. hosei, M. hulletti) that host plants also benefit considerably from ant-occupation. Ants do not contribute to the nutrient demands of their host plant, they do, however, protect it against herbivores and plant competition. Cleaning behaviour of the ants results in the removal of potential herbivores already in their earliest developmental stages. Strong aggressiveness and a mass recruiting system enable the ants to defend the host plant against many herbivorous insects. This results in a significant decrease in leaf damage due to herbivores on ant-occupied compared to ant-free myrmecophytes as well as compared to non-myrmecophytic Macaranga species. Most important is the ants' defense of the host plant against plant competitors, especially vines, which are abundant in the well-lit pioneer habitats where Macaranga grows. Ants bite off any foreign plant part coming into contact with their host plant. Both ant-free myrmecophytes and non-myrmecophytic Macaranga species had a significantly higher incidence of vine growth than specimens with active ant colonies. This may be a factor of considerable importance allowing Macaranga plants to grow at sites of strongest competition.
KW  - Ant/plant interaction
KW  - Myrmecophytes
KW  - Protection
KW  - Macaranga
KW  - Crematogaster borneensis
Y1  - 1989
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42857
ER  - 
TY  - JOUR
A1  - Maschwitz, Ulich
A1  - Fiala, Brigitte
A1  - Lee, Ying Fah
A1  - Chey, Vun Khen
A1  - Tan, Fui Lian
T1  - New and little-known myrmecophytic associations from Bornean rain forests
N2  - The woody climber Millettia niuewenhuisii (Fabaceae) and the shrub Myrmeconauclea strigosa (Rubiaceae) in Sabah, Borneo are associated with ants. The hollow stems of Millettia nieuwenhuisii are regularly inhabited by an aggressive Cladomyrma sp., which keeps pseudococcids inside the stem. On Myrmeconauclea strigosa the ants live in hollow internodal swellings near the end of the branches. In this plant many different ant species use the nesting space in an opportunistic manner.
Y1  - 1989
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42957
ER  - 
TY  - JOUR
A1  - Weising, Kurt
A1  - Fiala, Brigitte
T1  - Botanische Eindrücke vom Bako-Nationalpark / Sarawak
N2  - No abstract available
Y1  - 1992
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42947
ER  -