@misc{KlieglRolfsLaubrocketal.2009,
  author    = {Kliegl, Reinhold and Rolfs, Martin and Laubrock, Jochen and Engbert, Ralf},
  title     = {Microsaccadic Modulation of Response Times in Spatial Attention Tasks},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-57098},
  year      = {2009},
  abstract  = {Covert shifts of attention are usually reflected in RT differences between responses to valid and invalid cues in the Posner spatial attention task. Such inferences about covert shifts of attention do not control for microsaccades in the cue target interval. We analyzed the effects of microsaccade orientation on RTs in four conditions, crossing peripheral visual and auditory cues with peripheral visual and auditory discrimination targets. Reaction time was generally faster on trials without microsaccades in the cue-target interval. If microsaccades occurred, the target-location congruency of the last microsaccade in the cuetarget interval interacted in a complex way with cue validity. For valid visual cues, irrespective of whether the discrimination target was visual or auditory, target-congruent microsaccades delayed RT. For invalid cues, target-incongruent microsaccades facilitated RTs for visual target discrimination, but delayed RT for auditory target discrimination. No reliable effects on RT were associated with auditory cues or with the first microsaccade in the cue-target interval. We discuss theoretical implications on the relation about spatial attention and oculomotor processes.},
  language  = {en}
}
@misc{KlieglMassonRichter2009,
  author    = {Kliegl, Reinhold and Masson, Michael E. J. and Richter, Eike M.},
  title     = {A linear mixed model analysis of masked repetition priming},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-57073},
  year      = {2009},
  abstract  = {We examined individual differences in masked repetition priming by re-analyzing item-level response-time (RT) data from three experiments. Using a linear mixed model (LMM) with subjects and items specified as crossed random factors, the originally reported priming and word-frequency effects were recovered. In the same LMM, we estimated parameters describing the distributions of these effects across subjects. Subjects' frequency and priming effects correlated positively with each other and negatively with mean RT. These correlation estimates, however, emerged only with a reciprocal transformation of RT (i.e., -1/RT), justified on the basis of distributional analyses. Different correlations, some with opposite sign, were obtained (1) for untransformed or logarithmic RTs or (2) when correlations were computed using within-subject analyses. We discuss the relevance of the new results for accounts of masked priming, implications of applying RT transformations, and the use of LMMs as a tool for the joint analysis of experimental effects and associated individual differences.},
  language  = {en}
}
@misc{DimigenValsecchiSommeretal.2009,
  author    = {Dimigen, Olaf and Valsecchi, Matteo and Sommer, Werner and Kliegl, Reinhold},
  title     = {Human Microsaccade-Related Visual Brain Responses},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-56923},
  year      = {2009},
  abstract  = {Microsaccades are very small, involuntary flicks in eye position that occur on average once or twice per second during attempted visual fixation. Microsaccades give rise to EMG eye muscle spikes that can distort the spectrum of the scalp EEG and mimic increases in gamma band power. Here we demonstrate that microsaccades are also accompanied by genuine and sizeable cortical activity, manifested in the EEG. In three experiments, high-resolution eye movements were corecorded with the EEG: during sustained fixation of checkerboard and face stimuli and in a standard visual oddball task that required the counting of target stimuli. Results show that microsaccades as small as 0.15° generate a field potential over occipital cortex and midcentral scalp sites 100 -140 ms after movement onset, which resembles the visual lambda response evoked by larger voluntary saccades. This challenges the standard assumption of human brain imaging studies that saccade-related brain activity is precluded by fixation, even when fully complied with. Instead, additional cortical potentials from microsaccades were present in 86\% of the oddball task trials and of similar amplitude as the visual response to stimulus onset. Furthermore, microsaccade probability varied systematically according to the proportion of target stimuli in the oddball task, causing modulations of late stimulus-locked event-related potential (ERP) components. Microsaccades present an unrecognized source of visual brain signal that is of interest for vision research and may have influenced the data of many ERP and neuroimaging studies.},
  language  = {en}
}
@misc{JeličićFriedrichJeremićetal.2009,
  author    = {Jeličić, Aleksandra and Friedrich, Alwin and Jeremić, Katarina and Siekmeyer, Gerd and Taubert, Andreas},
  title     = {Polymer hydrogel/polybutadiene/iron oxide nanoparticle hybrid actuators for the characterization of NiTi implants},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-48589},
  year      = {2009},
  abstract  = {One of the main issues with the use of nickel titanium alloy (NiTi) implants in cardiovascular implants (stents) is that these devices must be of very high quality in order to avoid subsequent operations due to failing stents. For small stents with diameters below ca. 2 mm, however, stent characterization is not straightforward. One of the main problems is that there are virtually no methods to characterize the interior of the NiTi tubes used for fabrication of these tiny stents. The current paper reports on a robust hybrid actuator for the characterization of NiTi tubes prior to stent fabrication. The method is based on a polymer/hydrogel/magnetic nanoparticle hybrid material and allows for the determination of the inner diameter at virtually all places in the raw NiTi tubes. Knowledge of the inner structure of the raw NiTi tubes is crucial to avoid regions that are not hollow or regions that are likely to fail due to defects inside the raw tube. The actuator enables close contact of a magnetic polymer film with the inner NiTi tube surface. The magnetic signal can be detected from outside and be used for a direct mapping of the tube interior. As a result, it is possible to detect critical regions prior to expensive and slow stent fabrication processes.},
  language  = {en}
}
@misc{HeinkenWinkler2009,
  author    = {Heinken, Thilo and Winkler, Eckart},
  title     = {Non-random dispersal by ants : long-term field data versus model predictions of population spread of a forest herb},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-46482},
  year      = {2009},
  abstract  = {Myrmecochory, i.e. dispersal of seeds by ants towards and around their nests, plays an important role in temperate forests. Yet hardly any study has examined plant population spread over several years and the underlying joint contribution of a hierarchy of dispersal modes and plant demography. We used a seed-sowing approach with three replicates to examine colonization patterns of Melampyrum pratense, an annual myrmecochorous herb, in a mixed Scots pine forest in northeastern Germany. Using a spatially explicit individualbased (SEIB) model population patterns over 4 years were explained by short-distance transport of seeds by small ant species with high nest densities, resulting in random spread. However, plant distributions in the field after another 4 years were clearly deviating from model predictions. Mean annual spread rate increased from 0.9 m to 5.1 m per year, with a clear inhomogeneous component. Obviously, after a lag-phase of several years, non-random seed dispersal by large red wood ants (Formica rufa) was determining the species' spread, thus resulting in stratified dispersal due to interactions with different-sized ant species. Hypotheses on stratified dispersal, on dispersal lag, and on non-random dispersal were verified using an extended SEIB model, by comparison of model outputs with field patterns (individual numbers, population areas, and maximum distances). Dispersal towards red wood ant nests together with seed loss during transport and redistribution around nests were essential features of the model extension. The observed lag-phase in the initiation of non-random, medium-distance transport was probably due to a change of ant behaviour towards a new food source of increasing importance, being a meaningful example for a lag-phase in local plant species invasion. The results demonstrate that field studies should check model predictions wherever possible. Future research will show whether or not the M. pratense-ant system is representative for migration patterns of similar animal dispersal systems after having crossed range edges by long-distance dispersal events.},
  language  = {en}
}
@misc{MeierMeschenmoser2009,
  author    = {Meier, Bernd and Meschenmoser, Helmut},
  title     = {Qualit{\"a}tssicherung in Sch{\"u}lerfirmen : indikatorengest{\"u}tztes Qualit{\"a}tsraster zum Lehren und Lernen in einem arbeitsorientierten Lernarrangement},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-46186},
  year      = {2009},
  abstract  = {Sch{\"u}lerfirmen zeugen von der Innovationsf{\"a}higkeit der Schulen. Sie lassen auf Ver{\"a}nderungen des Unterrichts und des Selbstverst{\"a}ndnisses von Schule und Kollegien schließen, denn sie stehen im Kontrast zum traditionellen Fachunterricht. Ihre Existenz sagt allerdings relativ wenig {\"u}ber die damit verbundene Qualit{\"a}t aus. So ist zu kl{\"a}ren, welche Intentionen mit Qualit{\"a}tssicherung verbunden sind. Dar{\"u}ber hinaus wird ein Qualit{\"a}tsraster mit Indikatoren zur Analyse der Entwicklungsprozesse f{\"u}r Sch{\"u}lerfirmen zur Diskussion gestellt.},
  language  = {de}
}
@misc{MeierMeschenmoser2009,
  author    = {Meier, Bernd and Meschenmoser, Helmut},
  title     = {Sch{\"u}lerfirma Pausenschmaus arbeitet mit Erfolg},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-46177},
  year      = {2009},
  abstract  = {Mit Firma Pausenschmaus auf Erfolgskurs In diesem Material wird die Sch{\"u}lerfirma Pausenschmaus vorgestellt. Die Mitarbeiter der Firma Pausenschmaus sind schon gut vorangekommen. Sie haben mehrere Abteilungen gegr{\"u}ndet und gute Kunden gewonnen.},
  language  = {de}
}
@misc{MeierMeschenmoser2009,
  author    = {Meier, Bernd and Meschenmoser, Helmut},
  title     = {Zwischen Kundenwunsch und didaktischem Konzept : Sch{\"u}lerfirmen als integratives Lernarrangement arbeitsorientierter Bildung},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-46160},
  year      = {2009},
  abstract  = {Sch{\"u}lerfirmen haben im Bereich Arbeitslehre in j{\"u}ngster Zeit an Bedeutung gewonnen. Die Autoren stellen im Basisartikel des vorliegenden Heftes Lernen. Gewinn verschiedene Formen von Sch{\"u}lerfirmen vor und erl{\"a}utern Probleme bei der Sicherung der Lernqualit{\"a}t. Diese beziehen sich einerseits auf die optimale F{\"o}rderung arbeitsrelevanter Basiskompetenzen der Sch{\"u}ler und andererseits auf das Erreichen der curricularen Ziele der Arbeitslehre, insbesondere hinsichtlich der technischen und {\"o}konomischen Bildung sowie der Berufsorientierung. Zur Optimierung sind Lehrplankorrekturen, weitere Erfahrungen mit Sch{\"u}lerfirmen und die Unterst{\"u}tzung der Fachdidaktik notwendig. Wichtig sind zudem eine kollegiale Kooperation und Vernetzung an den Lernorten. Die Verfasser f{\"u}hren dar{\"u}ber hinaus in die Beitr{\"a}ge des vorliegenden Heftes ein.},
  language  = {de}
}
@misc{MeierMeschenmoser2009,
  author    = {Meier, Bernd and Meschenmoser, Helmut},
  title     = {Mal sehen, wie Tabea, Ali und ... in der Sch{\"u}lerfirma arbeiten : Lernen am und mit Modell},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-46153},
  year      = {2009},
  abstract  = {Die in den Materialien thematisierte Sch{\"u}lerfirma Pausenschmaus wurde als Prototyp f{\"u}r Lehr- und Lernzwecke modelliert. Die didaktische Modellvorstellung beruht auf Analysen existierender Sch{\"u}lerfirmen und bezieht sich auf die Forumsbeitr{\"a}ge zur Qualit{\"a}tssicherung in diesem Heft. Das Material gibt einerseits f{\"u}r den Unterricht wie f{\"u}r Lehrerfortbildung einen exemplarischen Orientierungsrahmen zur Gestaltung eigener Sch{\"u}lerfirmen, anderseits ist es Grundlage f{\"u}r komplexe Aufgabenstellungen zur arbeitsorientierten Bildung, wie sie im gesonderten Beitrag am Beispiel eines konkreten unternehmerischen Problems ausgef{\"u}hrt werden. Die Darstellungen im Material sind situativ angelegt, um somit Sch{\"u}lerinnen und Sch{\"u}ler an Prozesse und Strukturen von Unternehmen und damit befassten betrieblichen Funktionen heranzuf{\"u}hren. Das Modellunternehmen hat einen Schwerpunkt im Catering.},
  language  = {de}
}
@misc{VossBlenauWalzetal.2009,
  author    = {Voss, Martin and Blenau, Wolfgang and Walz, Bernd and Baumann, Otto},
  title     = {V-ATPase deactivation in blowfly salivary glands is mediated by protein phosphatase 2C},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-44360},
  year      = {2009},
  abstract  = {The activity of vacuolar H+-ATPase (V-ATPase) in the apical membrane of blowfly (Calliphora vicina) salivary glands is regulated by the neurohormone serotonin (5-HT). 5-HT induces, via protein kinase A, the phosphorylation of V-ATPase subunit C and the assembly of V-ATPase holoenzymes. The protein phosphatase responsible for the dephosphorylation of subunit C and V-ATPase inactivation is not as yet known. We show here that inhibitors of protein phosphatases PP1 and PP2A (tautomycin, ocadaic acid) and PP2B (cyclosporin A, FK-506) do not prevent V-ATPase deactivation and dephosphorylation of subunit C. A decrease in the intracellular Mg2+ level caused by loading secretory cells with EDTA-AM leads to the activation of proton pumping in the absence of 5-HT, prolongs the 5-HT-induced response in proton pumping, and inhibits the dephosphorylation of subunit C. Thus, the deactivation of V-ATPase is most probably mediated by a protein phosphatase that is insensitive to okadaic acid and that requires Mg2+, namely, a member of the PP2C protein family. By molecular biological techniques, we demonstrate the expression of at least two PP2C protein family members in blowfly salivary glands. © 2009 Wiley Periodicals, Inc.},
  language  = {en}
}