148 research outputs found

    Exploring new avenues for the meta-analysis method in personality and social psychology research

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    This dissertation addresses theoretical validity and bias in meta-analytic research in personality and social psychology research. The conceptual starting point of the dissertation is research on ego depletion (Baumeister et al., 1998). In this line of research, hundreds of studies documented an experimental effect that probably does not exist, as was later revealed by extensive replication work (Hagger et al., 2010, 2016). This debacle has presumably been caused by dysfunctional structures and procedures in psychological science, such as widespread publication bias (Carter & McCullough, 2014). Unfortunately, these dysfunctionalities were (and in some cases still are) also prevalent in other areas of psychological research beside ego depletion (Ferguson & Brannick, 2012; Open Science Collaboration, 2015). Because extensive replication research is too costly to be repeated for all past work, it has been a contentious question what to do with research data that has been generated during an era of questionable research practices: should this research be abandoned or can some of it be salvaged? In four research papers, this dissertation project attempts to address these questions. In part I of the dissertation project, two papers highlight and analyze challenges when summarizing past research in social psychology and personality research. Paper 1 (Friese et al., 2017) attempted to find summary evidence for the effectiveness of self-control training, a research field related to ego depletion, but came to a sobering conclusion: The summary effect was small, likely inflated by publication bias, and could not be attributed beyond doubt to a theoretical mechanism. Paper 2 (Friese & Frankenbach, 2020) reported on a simulation study that showed how multiple sources of bias (publication bias, p-hacking) can interact with contextual factors and each other to create significant meta-analytic evidence from very small or even zero true effects. Part II of the dissertation project is an attempt to advance social-psychological and personality theory with meta-scientific work despite an unknowable risk of bias in the literature. In part II, two papers (Frankenbach et al., 2020, 2022) make use of one key idea: Re-using existing raw research data to test novel theoretical ideas in secondary (meta-)analyses. Results revealed that this idea helps towards both goals of the dissertation project, that is, advancing theory while reducing risk-of-bias. The general discussion analyses promises and limitations of such secondary data analyses in more detail and attempts to situate the idea more broadly in the psychological research toolkit by contrasting integrative versus innovative research. Further discussion covers how conceptual and technological innovations may facilitate more secondary data analyses in the future, and how such advances may pave the way for a slower, more incremental, but truly valid and cumulative psychological science.Die vorliegende Dissertation behandelt theoretischen Validität und Verzerrung (Bias) von meta-analytischer Forschung in der Persönlichkeits- und Sozialpsychologie. Der konzeptuelle Ausgangspunkt der Dissertation ist die Forschung zu „Ego Depletion“ (Baumeister et al., 1998). In dieser Forschungslinie haben hunderte von Studien einen Effekt belegt, der, wie sich später durch umfangreiche Replikationsarbeiten (Hagger et al., 2010, 2016) herausstellte, vermutlich nicht existiert. Dieses Debakel wurde mutmaßlich mitverursacht durch dysfunktionale Strukturen und Prozesse in der psychologischen Forschung, insbesondere Publikationsbias („publication bias“). Unglücklicherweise lagen (und liegen) diese Dysfunktionalitäten neben Ego Depletion auch in anderen psychologischen Forschungsbereichen vor (Ferguson & Brannick, 2012; Open Science Collaboration, 2015). Da aus Kostengründen nicht alle Forschungsarbeiten der Vergangenheit repliziert werden können, ergibt sich eine kritische Frage: Wie soll mit psychologischer Forschung umgegangen werden, die unter mutmaßlich verzerrenden Bedingungen generiert wurde? Sollte diese Forschung ad acta gelegt werden oder können Teile davon weiterverwendet werden? Das vorliegende Dissertationsprojekt versucht im Rahmen von vier Forschungsbeiträgen sich diesen Fragen anzunähern. Im ersten Teil der Dissertation beleuchten und analysieren zwei Forschungsbeiträge Probleme und Herausforderungen, die sich bei der Zusammenfassung von bestehender Forschung der Sozial- und Persönlichkeitspsychologie ergeben. Der erste Beitrag (Friese et al., 2017) versucht in einer Meta-Analyse Evidenz für die Wirksamkeit von Selbstkontrolltrainings zu finden, aber kommt zu einem ernüchternden Ergebnis: Die Gesamteffekte sind klein, mutmaßlich durch Publikationsbias fälschlich überhöht und können überdies nicht zweifelsfrei einem theoretischen Kausalmechanismus zugeordnet werden. Der zweite Beitrag (Friese & Frankenbach, 2020) umfasst eine Simulationsstudie, die aufzeigt, wie verschiedene Formen von Bias (Publikationsbias und sog. „p-hacking“) miteinander und mit Kontextfaktoren interagieren können, wodurch signifikante, meta-analytische Effekte aus sehr kleinen wahren Effekten oder sogar Nulleffekten entstehen können. Der zweite Teil der Dissertation versucht, trotz eines unbestimmbaren Bias-Risikos, Fortschritte in der sozial- und persönlichkeitspsychologischen Theorie zu erzielen. Zu diesem Zweck wird in zwei Forschungsbeiträgen (Frankenbach et al., 2020, 2022) auf eine Schlüssel-Idee zurückgegriffen: Die Testung von neuen theoretischen Hypothesen unter Wiederverwendung von existierenden Forschungsdaten in Sekundärdatenanalysen. Die Ergebnisse zeigen, dass dieser Ansatz tatsächlich dazu beitragen kann, theoretische Fortschritte mit vermindertem Verzerrungsrisiko zu machen. Die anschließende, übergreifende Diskussion behandelt Möglichkeiten und Limitationen solcher Sekundärdatenanalysen und versucht, den Ansatz in einer Gegenüberstellung von integrativer und innovativer Forschung übergreifender in die psychologische Forschungsmethodik einzuordnen. Im Weiteren wird diskutiert, wie konzeptuelle und technologische Entwicklungen in der Zukunft Sekundärdatenanalysen erleichtern könnten und wie solche Fortschritte den Weg ebnen könnten für eine langsamere, inkrementelle, aber wahrhaft valide und kumulative psychologische Wissenschaft.German Research Foundation (DFG): "Die Rolle mentaler Anstrengung bei Ego Depletion

    Os estuários como sumidouros decarbono: fotossíntese, fotoinibição e resiliência da produtividade primária pelágica e bêntica

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    Estuaries are recognized amongst the most productive ecosystems on Earth. Their high primary productivity is largely due to the photosynthetic carbon fixation by phytoplankton and microphytobenthos, the communities of microalgae and cyanobacteria that inhabit the water column and subtidal or intertidal sediments, respectively. In comparison with the phytoplankton, the microphytobenthos has been much less studied regarding the photophysiological processes affecting primary productivity, and their relative role as contributors to estuarine-level production. One of these processes is photoinhibition, the high light-induced decrease in photosynthetic activity, considered a major limiting factor of growth and primary productivity in the variable and extreme estuarine environment. The detrimental impact of photoinhibition on photosynthesis depends on the balance between the photoinactivation and repair of photosystem II (PSII). By successfully adapting to microphytobenthos a recently-developed methodology based on multi-actinic imaging of chlorophyll fluorescence, this work evaluated their photoacclimation and photoprotective capacity, as measured by the reduction in PSII photoinactivation. PSII photoinactivation and repair was found to vary between different communities, pointing to a trade-off between cellular motility-based and physiological photoprotective mechanisms. Epipelic (motile) species showed a reduced physiological capacity for preventing photodamage, while epipsammic (non-motile) forms appeared less susceptible to photoinactivation and more dependent on physiological photoprotection. This work further investigated an overlooked aspect of microphytobenthos ecology, related to the presence of substantial amounts of microalgal biomass in subsurface sediments. By studying samples from intertidal areas of the Ria de Aveiro (Portugal), this work found that buried cells can quickly regain photosynthetic activity when exposed to surface conditions. Potential viable subsurface (0.5-10 cm) microalgal biomass was found to represent 2-3 times the amount of biomass present at the surface layers (0.0-0.5 cm). These results support the hypothesis that subsurface biomass may play an important ecological role as a source of photosynthetically competent cells capable of ‘reinoculating’ the surface, contributing to the high productivity of intertidal areas. The relative importance of phytoplankton and microphytobenthos as contributors to ecosystem-level primary productivity was evaluated in the Ria de Aveiro, by comparing the spatio-temporal variability of biomass and productivity of different communities. This study made use of a new type of fluorometer allowing the measurement of absolute rates of PSII electron transport rates and the estimation of carbon fixation rates. Biomass-specific productivity rates for phytoplankton and microphytobenthos were found to reach 68.0 and 19.1 mg C mg Chl a-1 d-1, respectively. Annual areal production rates were higher for the microphytobenthos, reaching 105.2 g C m-2 yr-1, as opposed to 49.9 g C m-2 yr-1 for the phytoplankton. The annual rates upscaled for the whole Ria de Aveiro highlight the importance of the intertidal areas as significant carbon sinks and reservoirs of active ‘blue carbon’, and as main sites of primary productivity, found to contribute with more than 60% of the total ecosystem-level budget 12428.3 t C yr-1.Os estuários são reconhecidos como um dos tipos de ecossistemas mais produtivos na Terra. A sua elevada produtividade primária é devida em larga medida à fixação fotossintética de carbono pelo fitoplâncton e microfitobentos, as comunidades de microalgas e cianobactérias que habitam a coluna de àgua e os sedimentos subtidais e intertidais, respetivamente. Em comparação com o fitoplâncton, o microfitobentos tem sido muito menos estudado relativamente aos processos fotofisiológicos que controlam a sua produtividade, bem como à sua contribuição para a produção primária global do estuário. Um destes processos é a fotoinibição, a diminuição da atividade fotossintética causada pela luz, considerada como um importante fator limitante da produtividade primária no ambiente estuarino. O impacto negativo da fotoinibição na fotossíntese depende do balanço entre a fotoinativação e a reparação do fotossistema II (PSII). Baseado num recente método de imagiologia multi-actínica de fluorescência da clorofila, este trabalho avaliou a fotoaclimatação e capacidade de fotoproteção contra a fotoinibição, medida pela redução da fotoinativação do PSII. A fotoinativação e reparação do PSII variou entre diferentes tipos de comunidades, indicando a existência de um balanço entre a fotoproteção baseada na motilidade celular e em mecanismos fisiológicos. Espécies epipélicas (móveis) mostraram uma menor capacidade fisiológica de prevenir danos, enquanto as formas epipsâmicas (imóveis) aparentaram ser menos suscetíveis à fotoinibição e mais dependentes de fotoproteção fisiológica. Este trabalho investigou ainda um aspeto pouco estudado, relacionado com a presença de quantidades substanciais de biomass de microalgas em sedimentos subsuperficias. Pela análise de sedimentos intertidais da Ria de Aveiro (Portugal), foi descoberto que as células enterradas conseguem recuperar rapidamente a sua atividade fotossintética quando expostas a condições da superfície. Foi também concluído que a biomassa subsuperficial (0.5-10 cm) potencialmente viável representa 2-3 vezes a biomassa presente nas camadas superficiais (0.0-0.5 cm). Estes resultados suportam a hipótese de que a biomassa subsuperficial desempenha um papel ecológico importante enquanto fonte de células fotossinteticamente competentes capazes de ‘reinocular’ a superfície, contribuindo para a elevada produtividade das áreas intertidais. A importância relativa da contribuição do fitoplâncton e do microfitobentos para a produtividade primária ao nível do ecossistema foi avaliada para a Ria de Aveiro, comparando a variabilidade espacio-temporal da biomass e produtividade de diferentes comunidades. Este estudo baseou-se na medição de taxas absolutas de transporte de electrões no PSII e a estimação de taxas de fixação de carbono. Por unidade de biomass, estas atingiram 68,0 e 19,1 mg C mg Chl a-1 d-1, para o fitoplâncton e o microfitobentos, respectivamente. Por unidade de área, a produtividade anual foi mais elevada no caso do microfitobentos, atingindo 105,2 g C m-2 yr-1, por oposição a 49,9 g C m-2 yr-1, para o fitoplâncton. Considerando a totalidade da área da Ria de Aveiro, os resultados salientam a importância das áreas intertidais enquanto sumidouros de carbono e reservatórios de “carbono azul”, e locais de elevada produtividade primária, contribuindo com mais de 60% do total anual de 12428,3 t C yr-1.Programa Doutoral em Biologi

    Age changes in size, energy metabolism and cardio-respiratory activities of thyroidectomized cattle

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    Publication authorized August 31, 1942.Digitized 2007 AES.Includes bibliographical references

    High-to-low CO2 acclimation reveals plasticity of the photorespiratory pathway and indicates regulatory links to cellular metabolism of Arabidopsis

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    Background: Photorespiratory carbon metabolism was long considered as an essentially closed and nonregulated pathway with little interaction to other metabolic routes except nitrogen metabolism and respiration. Most mutants of this pathway cannot survive in ambient air and require CO 2-enriched air for normal growth. Several studies indicate that this CO 2 requirement is very different for individual mutants, suggesting a higher plasticity and more interaction of photorespiratory metabolism as generally thought. To understand this better, we examined a variety of high- and low-level parameters at 1% CO 2 and their alteration during acclimation of wild-type plants and selected photorespiratory mutants to ambient air. Methodology and Principal Findings: The wild type and four photorespiratory mutants of Arabidopsis thaliana (Arabidopsis) were grown to a defined stadium at 1% CO 2 and then transferred to normal air (0.038% CO 2). All other conditions remained unchanged. This approach allowed unbiased side-by-side monitoring of acclimation processes on several levels. For all lines, diel (24 h) leaf growth, photosynthetic gas exchange, and PSII fluorescence were monitored. Metabolite profiling was performed for the wild type and two mutants. During acclimation, considerable variation between the individual genotypes was detected in many of the examined parameters, which correlated with the position of the impaired reaction in the photorespiratory pathway. Conclusions: Photorespiratory carbon metabolism does not operate as a fully closed pathway. Acclimation from high to low CO 2 was typically steady and consistent for a number of features over several days, but we also found unexpected short-term events, such as an intermittent very massive rise of glycine levels after transition of one particular mutant to ambient air. We conclude that photorespiration is possibly exposed to redox regulation beyond known substrate-level effects. Additionally, our data support the view that 2-phosphoglycolate could be a key regulator of photosynthetic-photorespiratory metabolism as a whole. © 2012 Timm et al

    Teaching evaluation - incentives to improve teaching quality

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    Die Evaluation der medizinischen Ausbildung wird am Fachbereich Medizin der J.W. Goethe – Universität Frankfurt seit 1998 systematisch durchgeführt. Damit ist diese Implementierung deutlich vor den bindenden Bestimmungen der Ärztlichen Approbationsordnung (in Kraft getreten am 01.10.2003) installiert worden. Die Evaluation der studentischen Lehre beinhaltet die Evaluierung sämtlicher Pflichtveranstaltungen (Kurse, Seminare, Praktika) durch einen standardisierten Fragebogen, der am Ende der Lehrpflichtveranstaltung (in jedem Semester) ausgeteilt und nach dem Ausfüllen durch die Studierenden wieder eingesammelt wird. In dieser Kommunikation belegen wir anhand ausgewählter Beispiele (vom Wintersemester 2003/2004 bis zum Wintersemester 2005/2006), dass die anderen Orts oft vorgetragenen negativen studentischen Bewertungen der vorklinischen Fächer an der J.W. Goethe – Universität nicht zutreffen (Bsp.:Kursus Anatomie I, Makroskopischer Teil, WS 2005/2006: M=1,8, SD=0,86). Die Bewertung der didaktischen Qualität („Lehrstoff wurde gut verständlich präsentiert“) ist bei den meisten vorklinischen Pflichtveranstaltungen zufriedenstellend (Bsp.: Kursus Anatomie I, Makroskopischer Teil, WS 2005/2006: M=2,06, SD=0,94). Aus diesen Ergebnissen schließen wir auf eine positive Rückwirkung des curricularen und didaktischen Umbaus des Medizinstudiums an der Goethe – Universität. Die Veröffentlichung der Ergebnisse der studentischen Evaluation („Zusammenfassende Beurteilung“) muss dem Umstand Rechnung tragen, dass praxisferne Fächer vielen Studierenden nur schwer zu vermitteln sind. Deswegen wird auf ein Ranking verzichtet. Nach diesen Ergebnissen wird ein Teil der Mittel leistungsorientiert vergeben (im jährlichen Zyklus). Diese leistungsorientierte Mittelvergabe (LOM) (davon 45 Prozent nach der studentischen Evaluation) beträgt 4 Prozent des jeweiligen Grundetats für Forschung und Lehre (Landeszuführung). Eine positive Lehrevaluation kann für eine Klinik/ein Institut einen wesentlich größeren Betrag bedeuten. Das Verfahren ist am Fachbereich akzeptiert

    Abschlussbericht: Evaluation der Niedersächsischen Aktionspläne Inklusion - Ein gemeinsames Projekt der Prognos AG und des Deutschen Instituts für Menschenrechte

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    Im Auftrag des Niedersächsichen Ministeriums für Soziales, Gesundheit und Gleichstellung haben die Prognos AG und die Monitoring-Stelle UN-Behindertenrechtskonvention des Deutschen Instituts für Menschenrechte die Niedersächsischen Aktionspläne Inklusion untersucht und Empfehlungen zur Fortschreibung abgegeben

    Are cyanobacteria a nearly immortal source of high market value compounds?

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    BACKGROUND: When the human population increases, so does the need to explore a wider range of feedstocks and biomasses, such as cyanobacteria. However, a deeper understanding of the growth patterns and pigment production is required to support the selection of the most beneficial species and conditions for industrial production. The growth and pigment production (i.e., chlorophyll a and C-phycocyanin) of three cyanobacterium species were evaluated following a three-fold aim. The first goal was to compare among a species commonly selected for exploitation (Arthrospira platensis) and two alternative species (Anabaena cylindrica and Nostoc muscorum). The second goal was analyzing pigment production in the long-term. The last goal involved comparing different methods (spectrophotometry and fluorimetry) to understand whether there is an appropriate proxy of biomass increase and pigment production that can be used for monitoring purposes. RESULTS: All species showed high longevity and proved capable of growing for more than 100 days without any additional supplementation. However, the maximum quantum yield of PS II (Fv /Fm) revealed that their photosynthetic efficiency varied over time with a clear decrease after 2 months. Pigment analysis showed a heterogeneous pattern during the growth periods of all three species that could only be captured by the parameter Fv /Fm, but the pattern was only present for A. cylindrica and N. muscorum in some stages of the culture period. CONCLUSION: N. muscorum was found to be the best chlorophyll a and C-phycocyanin producer, with the production peaking for all species at defined time periods within the growth profile. © 2022 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).publishe
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