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Die Wirksamkeit und der Nutzen von Psychotherapie sind vielfach nachgewiesen. Dennoch sind die der Psychotherapie zugrunde liegenden Wirk- und Veränderungsmechanismen zu einem großen Teil noch ungeklärt und werden kontrovers diskutiert. Ein vielversprechendes Untersuchungsdesign zur Überprüfung der Wirksamkeit und Wirkungsweise spezifischer psychotherapeutischer Techniken stellt die Untersuchung psychotherapeutischer Mikrointerventionen dar. In der vorliegenden Arbeit wurde ein laborexperimentelles Untersuchungsdesign zur Überprüfung der Wirksamkeit spezifischer psychotherapeutischer Techniken und damit einhergehender hirnphysiologischer Veränderungen erstmalig erprobt. Untersucht wurden die Effekte einer 90-minütigen psychotherapeutischen Mikrointervention, in der die Technik des kognitiven Reframings vermittelt und eingeübt wurde. Probanden einer subklinisch depressiven Stichprobe (N=45) sowie gesunde Kontrollpersonen (N=47) wurden randomisiert entweder der Mikrointervention oder einer von zwei Kontrollbedingungen zugeordnet. Die Überprüfung der interventionssezifischen Effekte erfolgte über die Erfassung ereigniskorrelierter Potenziale (EKPs) sowie Affekt-Ratings der Probanden. In einem spezifischen EEG-Paradigma wurden den Probanden negativ affektive Bilder gezeigt, die sie entweder aus einem neuen, positiven Blickwinkel betrachten oder nur anschauen sollten. Am Ende jedes Durchganges wurden die Probanden aufgefordert die Intensität ihrer emotionalen Reaktion einzuschätzen. Die Ergebnisse zeigen, dass die Psychotherapeutische Mikrointervention zu spezifischen Effekten, insbesondere auf der Ebene elektrokortikaler Veränderungen führte. Dabei wiesen die Probanden der Gruppe mit der psychotherapeutischen Mikrointervention größere mittlere frontale LPP Amplitudenwerte in Folge der Instruktionsbedingung "Umdeuten" auf. Die Ergebnisse werden im Sinne einer intensivierten kontrollierten Nutzung relevanter, über den präfrontalen Kortex vermittelter, kognitiver Verarbeitungsressourcen im Zusammenhang mit der Herunterregulierung emotionaler Reaktionen interpretiert.
The investigation concentrates on the exhibit of the known church-reformer, philosoph, cardinal and bishop of Brixen Nicolaus von Cues (1401 - 1464) concerning Jews. As origin we take the Jewish decree/ -statute wich mostly was publicated at diocesian an provicial synodes when von Cusanus was papal legate 1451 / 52 in Germany. The legate statet a ban for usury respectively restrictions of money-lending and a duty for identification. Among the decree sermons and letters from the legate-time are consulted. Appropriate parts concerning Jews an Judaism from empirical- and church-reformatoric scripts, sermons and notes from Cusanus areconsulted because the decree cannot be understood without the context of the complete works. So it is possible to disprove the thesis of a subordinated and marginal role of Jews in the cusanian work. To circumscribe the decree's consequences the constituted jewish settlements at 1451 / 55 in the german Empire are represented at cartographical base. As recessing example for the reactions to the decree the policy of Nürnberg is taken. The detailed correspondence of the council documents it's declining attitude. A finishing profile-analysis affords the possibility of a discussion on translation an reception of the Jewdecree in german countrys that's effect has to be evaluated regionally an locally sophisticated , on the base of the administratively regulated spaces by the church.
This paper tested the ability of Mandarin learners of German, whose native language has lexical tone, to imitate pitch accent contrasts in German, an intonation language. In intonation languages, pitch accents do not convey lexical information; also, pitch accents are sparser than lexical tones as they only associate with prominent words in the utterance. We compared two kinds of German pitch-accent contrasts: (1) a “non-merger” contrast, which Mandarin listeners perceive as different and (2) a “merger” contrast, which sounds more similar to Mandarin listeners. Speakers of a tone language are generally very sensitive to pitch. Hypothesis 1 (H1) therefore stated that Mandarin learners produce the two kinds of contrasts similarly to native German speakers. However, the documented sensitivity to tonal contrasts, at the expense of processing phrase-level intonational contrasts, may generally hinder target-like production of intonational pitch accents in the L2 (Hypothesis 2, H2). Finally, cross-linguistic influence (CLI) predicts a difference in the realization of these two contrasts as well as improvement with higher proficiency (Hypothesis 3, H3). We used a delayed imitation paradigm, which is well-suited for assessing L2-phonetics and -phonology because it does not necessitate access to intonational meaning. We investigated the imitation of three kinds of accents, which were associated with the sentence-final noun in short wh-questions (e.g., Wer malt denn Mandalas, lit: “Who draws PRT mandalas?” “Who likes drawing mandalas?”). In Experiment 1, 28 native speakers of Mandarin participated (14 low- and 14 high-proficient). The learners’ productions of the two kinds of contrasts were analyzed using General Additive Mixed Models to evaluate differences in pitch accent contrasts over time, in comparison to the productions of native German participants from an earlier study in our lab. Results showed a more pronounced realization of the non-merger contrast compared to German natives and a less distinct realization of the merger contrast, with beneficial effects of proficiency, lending support to H3. Experiment 2 tested low-proficient Italian learners of German (whose L1 is an intonation language) to contextualize the Mandarin data and further investigate CLI. Italian learners realized the non-merger contrast more target-like than Mandarin learners, lending additional support to CLI (H3).
Three Kinds of Rising-Falling Contours in German wh-Questions: Evidence From Form and Function
(2022)
The intonational realization of utterances is generally characterized by regional as well as inter- and intra-speaker variability in f0. Category boundaries thus remain “fuzzy” and it is non-trivial how the (continuous) acoustic space maps onto (discrete) pitch accent categories. We focus on three types of rising-falling contours, which differ in the alignment of L(ow) and H(igh) tones with respect to the stressed syllable. Most of the intonational systems on German have described two rising accent categories, e.g., L+H* and L*+H in the German ToBI system. L+H* has a high-pitched stressed syllable and a low leading tone aligned in the pre-tonic syllable; L*+H a low-pitched stressed syllable and a high trailing tone in the post-tonic syllable. There are indications for the existence of a third category which lies between these two categories, with both L and H aligned within the stressed syllable, henceforth termed (LH)*. In the present paper, we empirically investigate the distinctiveness of three rising-falling contours [L+H*, (LH)*, and L*+H, all with a subsequent low boundary tone] in German wh-questions. We employ an approach that addresses both the form and the function of the contours, also taking regional variation into account. In Experiment 1 (form), we used a delayed imitation paradigm to test whether Northern and Southern German speakers can imitate the three rising-falling contours in wh-questions as distinct contours. In Experiment 2 (function), we used a free association task to investigate whether listeners interpret the pragmatic meaning of the three contours differently. Imitation results showed that German speakers—both from the North and the South—reproduced the three contours. There was a small but significant effect of regional variety such that contours produced by speakers from the North were slightly more distinct than those by speakers from the South. In the association task, listeners from both varieties attributed distinct meanings to the (LH)* accent as opposed to the two ToBI accents L+H* and L*+H. Combined evidence from form and function suggests that three distinct contours can be found in the acoustic and perceptual space of German rising-falling contours.
The present study investigates the prosody of information-seeking (ISQs) and rhetorical questions (RQs) in Standard Chinese, in polar and wh-questions. Like in other languages, ISQs and RQs in Standard Chinese can have the same surface structure, allowing for a direct prosodic comparison between illocution types (ISQ vs RQ). Since Standard Chinese has lexical tone, the use of f0 as a cue to illocution type may be restricted. We investigate the prosodic differences between ISQs and RQs as well as the interplay of prosodic cues to RQs. In terms of f0, results showed that RQs were lower in f0, with the f0 range on the first word being expanded followed by f0 compression. RQs were further longer in duration and more often realized with non-modal voice quality (glottalized voice) as compared to ISQs. These prosodic cues were largely manipulated in tandem (illocutionary pairs with larger durational differences also showed larger differences in mean f0; voice quality, in turn, seemed to be an additional cue). We suggest three possible explanations (assertive force, focus, speaker attitude) that unite the present findings on RQs in Standard Chinese with the findings on RQs in other, non-tonal languages.
Ziel der Studie war es, die Wirksamkeit zweier psychotherapeutischer Mikrointerventionen zur Emotionsregulation und zur progressiven Relaxation und die damit einhergehenden Veränderungen auf psychometrischer und elektrokortikaler Ebene zu untersuchen. Die Stichprobe bestand aus 65 klinischen Versuchspersonen der Warteliste der Poliklinischen Psychotherapieambulanz der Universität Trier. In einer EEG-Erhebung vor und nach den Mikrointerventionen wurden neben dem Ruhe-EEG ereigniskorrelierte Potentiale (EKPs) aufgezeichnet. Im EKP-Paradigma wurden die Probanden instruiert negativ-valente Bilder aus dem IAPS-System entweder anzuschauen oder die gezeigte Situation kognitiv zu einer weniger negativen Interpretation der Bilder umzudeuten. Nach der EEG-Aufzeichnung wurden die Probanden randomisiert einer standardisierten 90-minütigen psychotherapeutischen Intervention zum kognitiven Reframing bzw. zur progressiven Relaxation zugewiesen. Im Anschluss wurde die EEG-Erhebung mit dem Ruhe-EEG und dem EKP mit einem parallelisierten Pool negativ valenter Bilder erneut durchgeführt. Auf psychometrischer Ebene wurde u.a. der positive und negative Affekt mit dem PANAS im Verlauf der Untersuchung zu insgesamt vier Messzeitpunkten erfasst. Neben dem Alpha-Frequenzband des Ruhe-EEGs wurde bei den EKPs die P3 und das Späte Positive Potential (LPP) untersucht. Die Ergebnisse geben Hinweise darauf, dass die psychotherapeutischen Mikrointerventionen zu differentiellen Effekten auf psychometrischer und elektrokortikaler Ebene führten. Auf der psychometrischen Ebene zeigte sich bei den Teilnehmern der Entspannungsintervention direkt nach der Intervention eine Abnahme des negativen Affekts, während sich dies bei den Teilnehmern der Reframing-Intervention erst im Verlauf der zweiten EEG-Messung mit dem Umdeuten der negativ valenten Bilder zeigte. Auf der elektrokortikalen Ebene waren die Ergebnisse weniger einheitlich. Durch die Entspannungs-Intervention konnte im Verlauf der Untersuchung eine Zunahme der P3-Amplituden festgestellt werden, während die Reframing-Teilnehmer über die Messzeitpunkte eine Abnahme der P3-Amplituden aufwiesen. Dies könnte so interpretiert werden, dass durch das Erlernen des Reframings das emotionale Arousal reduziert werden konnte. Bei dem LPP waren hingegen keine differentiellen Effekte der Mikrointerventionen nachweisbar. Bei beiden Interventionen kam es zu einer Zunahme der LPP-Amplituden. Bei der Analyse der Alpha-Aktivität des Ruhe-EEGs wurde bei den Entspannungs-Teilnehmern im Vergleich zu den Reframing-Teilnehmern nach der Mikrointervention eine größere Alpha-Aktivität gefunden. Diese Unterschiede wurden am deutlichsten in der linken Hemisphäre sowie in den zentralen und parietalen Hirnregionen. Eine höhere Alpha-Aktivität geht mit einer niedrigeren kortikalen Aktivität einher, so dass man davon ausgehen kann, dass die Entspannungs-Teilnehmer diese Hirnregionen während der Intervention weniger ausgeprägt nutzten. Zusammenfassend geben die Befunde erste Hinweise auf eine differentielle Wirkung der beiden Mikrointerventionen.
Interaction between the Hypothalamic-Pituitary-Adrenal Axis and the Circadian Clock System in Humans
(2018)
Rotation of the Earth creates day and night cycles of 24 h. The endogenous circadian clocks sense these light/dark rhythms and the master pacemaker situated in the suprachiasmatic nucleus of the hypothalamus entrains the physical activities according to this information. The circadian machinery is built from the transcriptional/translational feedback loops generating the oscillations in all nucleated cells of the body. In addition, unexpected environmental changes, called stressors, also challenge living systems. A response to these stimuli is provided immediately via the autonomic-nervous system and slowly via the hypothalamus"pituitary"adrenal (HPA) axis. When the HPA axis is activated, circulating glucocorticoids are elevated and regulate organ activities in order to maintain survival of the organism. Both the clock and the stress systems are essential for continuity and interact with each other to keep internal homeostasis. The physiological interactions between the HPA axis and the circadian clock system are mainly addressed in animal studies, which focus on the effects of stress and circadian disturbances on cardiovascular, psychiatric and metabolic disorders. Although these studies give opportunity to test in whole body, apply unwelcome techniques, control and manipulate the parameters at the high level, generalization of the results to humans is still a debate. On the other hand, studies established with cell lines cannot really reflect the conditions occurring in a living organism. Thus, human studies are absolutely necessary to investigate mechanisms involved in stress and circadian responses. The studies presented in this thesis were intended to determine the effects of cortisol as an end-product of the HPA axis on PERIOD (PER1, PER2 and PER3) transcripts as circadian clock genes in healthy humans. The expression levels of PERIOD genes were measured under baseline conditions and after stress in whole blood. The results demonstrated here have given better understanding of transcriptional programming regulated by pulsatile cortisol at standard conditions and short-term effects of cortisol increase on circadian clocks after acute stress. These findings also draw attention to inter-individual variations in stress response as well as non-circadian functions of PERIOD genes in the periphery, which need to be examined in details in the future.
The classic Capital Asset Pricing Model and the portfolio theory suggest that investors hold the market portfolio to diversify idiosyncratic risks. The theory predicts that expected return of assets is positive and that reacts linearly on the overall market. However, in reality, we observe that investors often do not have perfectly diversified portfolios. Empirical studies find that new factors influence the deviation from the theoretical optimal investment. In the first part of this work (Chapter 2) we study such an example, namely the influence of maximum daily returns on subsequent returns. Here we follow ideas of Bali et al. (2011). The goal is to find cross-sectional relations between extremely positive returns and expected average returns. We take account a larger number of markets worldwide. Bali et al. (2011) report with respect to the U.S. market a robust negative relation between MAX (the maximum daily return) and the expected return in the subsequent time. We extent substantially their database to a number of other countries, and also take more recent data into account (until end of 2009). From that we conclude that the relation between MAX and expected returns is not consistent in all countries. Moreover, we test the robustness of the results of Bali et al. (2011) in two time-periods using the same data from CRSP. The results show that the effect of extremely positive returns is not stable over time. Indeed we find a negative cross-sectional relation between the extremely positive returns and the average returns for the first half of the time series, however, we do not find significant effects for the second half. The main results of this chapter serve as a basis for an unpublished working paper Yuan and Rieger (2014b). While in Chapter 2 we have studied factors that prevent optimal diversification, we consider in Chapter 3 and 4 situations where the optimal structure of diversification was previously unknown, namely diversification of options (or structured financial products). Financial derivatives are important additional investment form with respect to diversification. Not only common call and put options, but also structured products enable investors to pursue a multitude of investment strategies to improve the risk-return profile. Since derivatives become more and more important, diversification of portfolios with dimension of derivatives is of particularly practical relevance. We investigate the optimal diversification strategies in connection with underlying stocks for classical rational investors with constant relative risk aversion (CRRA). In particular, we apply Monte Carlo method based on the Black-Scholes model and the Heston model for stochastic volatility to model the stock market processes and the pricing of the derivatives. Afterwards, we compare the benchmark portfolio which consists of derivatives on single assets with derivatives on the index of these assets. First we compute the utility improvement of an investment in the risk-free assets and plain-vanilla options for CRRA investors in various scenarios. Furthermore, we extend our analysis to several kinds of structured products, in particular capital protected notes (CPNs), discount certificates (DCs) and bonus certificates (BCs). We find that the decision of an investor between these two diversification strategies leads to remarkable differences. The difference in the utility improvement is influenced by risk-preferences of investors, stock prices and the properties of the derivatives in the portfolio. The results will be presented in Chapter 3 and are the basis for a yet unpublished working paper Yuan and Rieger (2014a). To check furthermore whether underlyings of structured products influence decisions of investors, we discuss explicitly the utility gain of a stock-based product and an index-based product for an investor whose preferences are described by cumulative prospect theory (CPT) (Chapter 4, compare to Yuan (2014)). The goal is that to investigate the dependence of structured products on their underlying where we put emphasis on the difference between index-products and single-stock-products, in particular with respect to loss-aversion and mental accounting. We consider capital protected notes and discount certificates as examples, and model the stock prices and the index of these stocks via Monte Carlo simulations in the Black-Scholes framework. The results point out that market conditions, particularly the expected returns and volatility of the stocks play a crucial role in determining the preferences of investors for stock-based CPNs and index-based CPNs. A median CPT investor prefers the index-based CPNs if the expected return is higher and the volatility is lower, while he prefers the stock-based CPNs in the other situation. We also show that index-based DCs are robustly more attractive as compared to stock-based DCs for CPT investors.
Das Motiv "Wasser" in der Kunst " unter Berücksichtigung der Werke Bill Violas und Fabrizio Plessis
(2008)
Wasser ist ein beliebtes Motiv in allen Kunstepochen. Der Grund für die Beliebtheit des Wassers als Sujet bei Künstlerinnen und Künstlern liegt einerseits an seiner existenziellen und kulturellen Bedeutung für das menschliche Leben und andererseits an seinen physikalischen Eigenschaften mit den daraus resultierenden vielfältigen gestalterischen Möglichkeiten. Auch in der Videokunst wird es häufig als Gegenstand aufgegriffen. Insbesondere Bill Viola (1952, USA), der tief von der östlichen Philosophie beeinflusst ist, und Fabrizio Plessi (1940, Italien) stellen in ihren Werken ein je besonderes Verhältnis zwischen Video und Wasser dar. Die vorliegende Arbeit befasst sich zunächst mit einer vergleichenden Be-trachtung der Bedeutung des Wassers in der westlichen und östlichen Kultur und einem Überblick über das Motiv in der Kunst vom Mittelalter bis zum 20. Jahrhundert. Im Mittelpunkt dieser Arbeit steht die Untersuchung der Videoskulpturen, Videoinstallationen und Videobänder Bill Violas und Fabrizio Plessis. Erörtert werden folgende Fragen: In welcher Weise hat das Wasser ästhetische, formale, inhaltliche oder symbolische sowie persönliche Bedeutung für die einzelnen Künstler? Auf welche Art haben sie ihre Vorstellungen in die Arbeiten umgesetzt? Wie weit wird dieses tradierte Thema und in welcher Form wird das natürliche Element in der Videokunst durch das moderne, technische Medium wieder aufgegriffen, weiter entwickelt oder modifiziert? Aus diesen Beobachtungen heraus zeigt die Autorin die Charakteristika der mit technischen Medien produzierten Kunstwerke der besprochenen Künstler bei der Verwendung des Motivs Wasser auf.
Do Personality Traits, Trust and Fairness Shape the Stock-Investing Decisions of an Individual?
(2023)
This thesis is comprised of three projects, all of which are fundamentally connected to the choices that individuals make about stock investments. Differences in stock market participation (SMP) across countries are large and difficult to explain. The second chapter focuses on differences between Germany (low SMP) and East Asian countries (mostly high SMP). The study hypothesis is that cultural differences regarding social preferences and attitudes towards inequality lead to different attitudes towards stock markets and subsequently to different SMPs. Using a large-scale survey, it is found that these factors can, indeed, explain a substantial amount of the country differences that other known factors (financial literacy, risk preferences, etc.) could not. This suggests that social preferences should be given a more central role in programs that aim to enhance SMP in countries like Germany. The third chapter documented the importance of trust as well as herding for stock ownership decisions. The findings show that trust as a general concept has no significant contribution to stock investment intention. A thorough examination of general trust elements reveals that in group and out-group trust have an impact on individual stock market investment. Higher out group trust directly influences a person's decision to invest in stocks, whereas higher in-group trust increases herding attitudes in stock investment decisions and thus can potentially increase the likelihood of stock investments as well. The last chapter investigates the significance of personality traits in stock investing and home bias in portfolio selection. Findings show that personality traits do indeed have a significant impact on stock investment and portfolio allocation decisions. Despite the fact that the magnitude and significance of characteristics differ between two groups of investors, inexperienced and experienced, conscientiousness and neuroticism play an important role in stock investments and preferences. Moreover, high conscientiousness scores increase stock investment desire and portfolio allocation to risky assets like stocks, discouraging home bias in asset allocation. Regarding neuroticism, a higher-level increases home bias in portfolio selection and decreases willingness to stock investment and portfolio share. Finally, when an investor has no prior experience with portfolio selection, patriotism generates home bias. For experienced investors, having a low neuroticism score and a high conscientiousness and openness score seemed to be a constant factor in deciding to invest in a well-diversified international portfolio