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The parables of Jesus have undergone different transmutations in the long history of their transmission. The events surrounding his death and resurrection as well as the new situations his followers were confronted with after these events, led to the parables being given new accentuation according to the needs of the reflecting community. This is evident in Matthew's treatment of the parable trilogy of Mt 21:28-22:14. The work tries to show how Matthew has used the dominical parables and sayings found in his tradition to serve the needs of his community, especially in her struggles with the official Jewish leaders of his time. Through these parables, which he presented as a three-pronged attack against the Jewish leaders, he shows his community as the true Israel, called to produce the fruits of righteousness.
Renewal of fear is one form of relapse that occurs after successful therapy, resulting from an encounter with a feared object in a context different from the context of the exposure therapy. According to Bouton (1994), the return of fear, provoked by context change, indicates that the fear was not erased in the first place. More importantly, the return of fear indicates that during the exposure session a new association was learned that connected the feared object with “no fear”; yet, as Bouton further argues, this association is context dependent. Such dependence could explain effects like renewal. In a new context, the therapeutic association will not be expressed and thus will no longer inhibit the fear. The assumption that an association is context dependent has been tested and showed robust results (Balooch & Neumann, 2011; Siavash Bandarian Balooch, Neumann, & Boschen, 2012; Culver, Stoyanova, & Craske, 2011; Kim & Richardson, 2009; Neumann & Kitlertsirivatana, 2010). Research for the treatment of anxiety disorders, aiming to reduce fear and, more importantly, prevent relapse, is flourishing. There are several exposure protocols currently under investigation: multiple contexts exposure (MCE), which aims at reducing the return of fear due to renewal (e.g., Balooch & Neumann, 2011); prolonged exposure (PE), which aims at strengthening the inhibitory association during the extinction learning (e.g., Thomas, Vurbic, & Novak, 2009); and reconsolidation update (RU), which aims at “updating” the reconsolidation process by briefly exposing the CS+ before the actual extinction takes place (Schiller et al., 2010). So far, however, few clinical studies conducted on humans have investigated these novel treatment protocols, and as far as I know none has investigated the mechanisms of action behind these protocols with a human clinical sample. The present thesis has three main goals. The first is to demonstrate that exposure therapy in multiple contexts reduces the likelihood of renewal. The second is to examine the mechanisms contributing to the effect of MCE and the third is to shed light on the concept of context in the framework of the conditioning and extinction paradigm. To this end, three studies were conducted. The first study investigated the effect of MCE on renewal, the second and third studies examined working mechanisms of MCE. In the first study thirty spider-phobic participants were exposed four times to a virtual spider. The exposure trials were conducted either in one single context or in four different contexts. Finally, all participants completed both a virtual renewal test, with the virtual spider presented in a novel virtual context, and an in vivo behavioral avoidance test with a real spider. This study successfully demonstrated the efficacy of MCE on reducing renewal. Study 2 investigated the working mechanisms behind MCE by utilizing a differential conditioning paradigm and conducting the extinction in multiple contexts, targeting similar renewal attenuation as achieved in study 1. This was followed by two tests that attempted to reveal extinction-relevant associations like ones causing context inhibitory effects. This study had three main hypotheses: (1) The extinction context is associated with the exposure, and thus operates as a safety signal at some point during the extinction; it will therefore compete with the safety learning of the CS, leading to a decreased extinction effect on the CS if the extinction is conducted in only one context. (2) The elements (e.g., room color, furniture) of the extinction context are connected to the therapeutic association and therefore should serve as reminders of the extinction, causing a stronger fear inhibition when presented during a test. (3) Therapy process factors, according to emotional processing theory, determine the renewal effect (e.g., initial fear activation, and within-session and between-session activation are correlated with the strength of renewal). In this study, however, no differences between the groups at the renewal phase were observed, presumably because the extinction was too strong to enable a renewal of fear at the test phase conducted immediately following the extinction. This hence rendered the two inhibitory tests useless. Study 3 aimed at defining the concept of context in the conditioning and exposure framework. Study 3 utilized the phenomenon known as generalization decrement, whereby a conditioned response is reduced due to change in the environment. This allowed context similarity to be quantified. After an acquisition phase in one context, participants were tested in one of three contexts, two of which differed in only one dimension (configuration of objects vs. features). The third group was tested in the same context and served as control group. The goal was to show that both configuration and features play an important role in the definition of context. There was, however, no significant statistical difference between the groups at the test phases, likely because of context novelty effects (participants exposed to a new context following extinction in another context expected a second extinction phase, and thus demonstrated greater fear than expected in all three groups).
The aim of this study was both to investigate the influence of cognitive control on unconscious processing, and to investigate the influence of unconscious processing on cognitive control. At first, different mechanisms and accounts to explain unconscious priming are presented. Here, perceptual and motor processes, as well as stimulus-response learning, semantic categorization, and the action trigger account as theories to explain motor priming are discussed. Then, the issue of the potential limits of unconscious processing is presented. Findings that indicate that active current intentions and expertise modulate unconscious processing are illustrated. Subsequently, results that imply an influence of unconsciously presented stimuli that goes beyond motor processes are discussed, with a special focus on inhibition processes, orienting of attention, task set activation, and conflict adaptation. Then I present the results of my own empirical work. Experiment 1 shows that the effective processing of unconsciously presented stimuli depends on expertise, even when potentially confounding difference between the expert and novice groups are controlled. The results of Experiments 2 and 3 indicate that the intention to use particular stimuli is a crucial factor for the effectiveness of these stimuli when they are presented unconsciously. Additionally, these findings show that shifts of attention can be triggered by centrally presented masked arrow cues. Experiments 4 and 5 broaden these results to cue stimuli that are not inherently associated with a spatial meaning. The finding corroborate that typically endogenously controlled shifts of attention can also be induced by unconscious stimuli. Experiments 6 and 7 demonstrate that even a central cognitive control process like task set activation is not contingent on conscious awareness, but can in contrast be triggered through unconscious stimulation. Finally, these results are integrated and I discuss how the concept of cognitive control and the limits of unconscious processing may have to be reconsidered. Furthermore, potential future research possibilities in this field are presented.
The work presents a performance evaluation and optimization of so-called overlay networks for content distribution in the Internet. Chapter 1 describes the importance which have such networks in today's Internet, for example, for the transmission of video content. The focus of this work is on overlay networks based on the peer-to-peer principle. These are characterized by the fact that users who download content, also contribute to the distribution process by sharing parts of the data to other users. This enables efficient content distribution because each user not only consumes resources in the system, but also provides its own resources. Chapter 2 of the monograph contains a detailed description of the functionality of today's most popular overlay network BitTorrent. It explains the various components and their interaction. This is followed by an illustration of why such overlay networks for Internet service providers (ISPs) are problematic. The reason lies in the large amount of inter-ISP traffic that is produced by these overlay networks. Since this inter-ISP traffic leads to high costs for ISPs, they try to reduce it by improved mechanisms for overlay networks. One optimization approach is the use of topology awareness within the overlay networks. It provides users of the overlay networks with information about the underlying physical network topology. This allows them to avoid inter-ISP traffic by exchanging data preferrentially with other users that are connected to the same ISP. Another approach to save inter-ISP traffic is caching. In this case the ISP provides additional computers in its network, called caches, which store copies of popular content. The users of this ISP can then obtain such content from the cache. This prevents that the content must be retrieved from locations outside of the ISP's network, and saves costly inter-ISP traffic in this way. In the third chapter of the thesis, the results of a comprehensive measurement study of overlay networks, which can be found in today's Internet, are presented. After a short description of the measurement methodology, the results of the measurements are described. These results contain data on a variety of characteristics of current P2P overlay networks in the Internet. These include the popularity of content, i.e., how many users are interested in specific content, the evolution of the popularity and the size of the files. The distribution of users within the Internet is investigated in detail. Special attention is given to the number of users that exchange a particular file within the same ISP. On the basis of these measurement results, an estimation of the traffic savings that can achieved by topology awareness is derived. This new estimation is of scientific and practical importance, since it is not limited to individual ISPs and files, but considers the whole Internet and the total amount of data exchanged in overlay networks. Finally, the characteristics of regional content are considered, in which the popularity is limited to certain parts of the Internet. This is for example the case of videos in German, Italian or French language. Chapter 4 of the thesis is devoted to the optimization of overlay networks for content distribution through caching. It presents a deterministic flow model that describes the influence of caches. On the basis of this model, it derives an estimate of the inter-ISP traffic that is generated by an overlay network, and which part can be saved by caches. The results show that the influence of the cache depends on the structure of the overlay networks, and that caches can also lead to an increase in inter-ISP traffic under certain circumstances. The described model is thus an important tool for ISPs to decide for which overlay networks caches are useful and to dimension them. Chapter 5 summarizes the content of the work and emphasizes the importance of the findings. In addition, it explains how the findings can be applied to the optimization of future overlay networks. Special attention is given to the growing importance of video-on-demand and real-time video transmissions.
This study explores novelty choice, a behavioral paradigm for the investigation of visual pattern recognition and learning of the fly Drosophila melanogaster in the flight simulator. Pattern recognition in novelty choice differs significantly from pattern recognition studied by heat conditioning, although both paradigms use the same test. Out of the four pattern parameters that the flies can learn in heat conditioning, novelty choice can be shown for height (horizontal bars differing in height), size and vertical compactness but not for oblique bars oriented at +/- 45°. Upright and inverted Ts [differing in their centers of gravity (CsOG) by 13°] that have been extensively used for heat conditioning experiments, do not elicit novelty choice. In contrast, horizontal bars differing in their CsOG by 13° do elicit novelty choice; so do the Ts after increasing their CsOG difference from 13° to 23°. This indicates that in the Ts the heights of the CsOG are not the only pattern parameters that matter for the novelty choice behavior. The novelty choice and heat conditioning paradigms are further differentiated using the gene rutabaga (rut) coding for a type 1 adenylyl cyclase. This protein had been shown to be involved in memory formation in the heat conditioning paradigm. Novelty choice is not affected by mutations in the rut gene. This is in line with the finding that dopamine, which in olfactory learning is known to regulate Rutabaga via the dopamine receptor Dumb in the mushroom bodies, is dispensable for novelty choice. It is concluded that in novelty choice the Rut cAMP pathway is not involved. Novelty choice requires short term working memory, as has been described in spatial orientation during locomotion. The protein S6KII that has been shown to be involved in visual orientation memory in walking flies is found here to be also required for novelty choice. As in heat conditioning the central complex plays a major role in novelty choice. The S6KII mutant phenotype for height can be rescued in some subsets of the ring neurons of the ellipsoid body. In addition the finding that the ellipsoid body mutants ebo678 and eboKS263 also show a mutant phenotype for height confirm the importance of ellipsoid body for height novelty choice. Interestingly some neurons in the F1 layer of the fan-shaped body are necessary for height novelty choice. Furthermore, different novelty choice phenotypes for different pattern parameters are found with and without mushroom bodies. Mushroom bodies are required in novelty choice for size but they are dispensable for height and vertical compactness. This special circuit requirement for the size parameter in novelty choice is found using various means of interference with mushroom body function during development or adulthood.
The subject of this work was to develop, implement, optimize and apply methods for quantitative MR imaging of tumors. In the context of functional and physiological characterization, this implied transferring techniques established in tumor model research to human subjects and assessing their feasibility for use in patients. In the context of the morphologic assessment and parameter imaging of tumors, novel concepts and techniques were developed, which facilitated the simultaneous quantification of multiple MR parameters, the generation of “synthetic” MR images with various contrasts, and the fast single-shot acquisition of purely T2-weighted images.
The tendency towards the exploitation of the resources of creation is the result of a long historical and cultural process. The modern African Communities have witnessed man’s growing capacity for environmental transformative intervention. The aspect of the conquest and exploitation of resources in rural communities such as in the Niger Delta of Nigeria has become predominant and invasive, and has even reached the point of threatening the environment’s hospitable function: the environment only as resource risks threatening the environment as home. In this respect, the ethical judgement of the social realities on ground is very decisive. And this is the very important aspect where the Catholic Social Ethics has a role to play. Because of the environmental crisis in this region through technological advancement, there is urgent need for a balance through the introduction of the model of a sustainable development.
The socio-ethical model of sustainability in this work is a framework so constructed that women, men, families and communities in the Niger Delta are to be the agents which determine what their developmental strategies are. Although their developmental opportunities and decisions are sometimes constrained by various factors, it remains the fact that they alone bear responsibility for their environment and must live with the consequences.
So if sustainable development in the Niger Delta region of Nigeria is to extend beyond narrow technical understanding, it must one that generally seek to embrace the cultural and social systems of the people. This will go a long way in reducing dependency and increase self-empowerment and will place more value on what the people understand and practice.
Bede Chinedum Nwadinobi, a native of Alike Obowo in Imo State (Nigeria), is a Catholic Priest of Okigwe Diocese (Nigeria). He studied Philosophy and Theology at St. Joseph Major Seminary Ikot-Ekpene. He also worked as a Vice-Principal of Queen of Apostles College Okigwe (Nigeria). At the University of Würzburg (Germany), he earned his doctorate in Catholic Theology specializing in Catholic Social Science.
The glaciers in Norway exert a strong influence on Norwegian economy and society. Unlike many glaciers elsewhere and despite ongoing climate change and warming, many of them showed renewed advances and positive net mass changes in the 1980's and 1990's, followed by rapid retreats and mass losses since 2000. This difference in behaviour may be attributed to differences and shifts in the glaciological regime - the differences in the magnitude of impacts of climatic and non-climatic geographical factors on the glacier mass.
This study investigates the influence of various atmospheric variables on mass balance changes of a selection of glaciers in Norway by means of Pearson correlation analyses and cross-validated stepwise multiple regression analyses. The analyses are carried out for three time periods (1949-2008, 1949-1988, 1989-2008) separately in order to take into consideration the possible shift in the glaciological regime in the 1980's. The atmospheric variables are constructed from ERA40 and NCEP/NCAR re-analysis datasets and include regional means of seasonal air temperature and precipitation rates and atmospheric circulation indices. The multiple regression models trained in these time periods are then applied to predictors reconstructed from the CMIP3 climate model dataset to generate an estimate for mass changes from the year 1950 to 2100. The temporal overlap of estimates and observations is used for calibration. Finally, observed atmospheric states in seasons that are characterised by a particularly positive or negative mass balance are categorised into time periods of modelled climate by the application of a Bayesian classification procedure.
The strongest influence on winter mass balance is exerted by different indices of the North Atlantic Oscillation (NAO), Northern Annular Mode (NAM) and precipitation. The correlation coefficients and explained variances determined from the multiple regression analyses reveal an East-West gradient, suggesting a weaker influence of the NAO and NAM on glaciers underlying a more continental regime. The highest correlation coefficients and explained variances were obtained for the 1989-2008 time period, which might be due to a strong and predominantly positive phase of the NAO. Multi-model ensemble means of the estimates show a mass loss for all three eastern glaciers, while the estimates for the more maritime glaciers are ambivalent. In general, the estimates show a greater sensitivity to the training time period than to the greenhouse gas emission scenarios according to which the climates were simulated. The average net mass change by the end of 2100 is negative for all glaciers except for the northern Engabreen. For many glaciers, the Bayesian classification of observed atmospheric states into time periods of modelled climate reveals a decrease in probability of atmospheric states favouring extremes in winter, and an increase in probability of atmospheric states favouring extreme mass loss in summer for the distant future (2071-2100). This pattern of probabilities for the ablation season is most pronounced for glaciers underlying a continental and intermediate regime.
The work at hand studies problems from Loewner theory and is divided into two parts:
In part 1 (chapter 2) we present the basic notions of Loewner theory. Here we use a modern form which was developed by F. Bracci, M. Contreras, S. Díaz-Madrigal et al. and which can be applied to certain higher dimensional complex manifolds.
We look at two domains in more detail: the Euclidean unit ball and the polydisc. Here we consider two classes of biholomorphic mappings which were introduced by T. Poreda and G. Kohr as generalizations of the class S.
We prove a conjecture of G. Kohr about support points of these classes. The proof relies on the observation that the classes describe so called Runge domains, which follows from a result by L. Arosio, F. Bracci and E. F. Wold.
Furthermore, we prove a conjecture of G. Kohr about support points of a class of biholomorphic mappings that comes from applying the Roper-Suffridge extension operator to the class S.
In part 2 (chapter 3) we consider one special Loewner equation: the chordal multiple-slit equation in the upper half-plane.
After describing basic properties of this equation we look at the problem, whether one can choose the coefficient functions in this equation to be constant. D. Prokhorov proved this statement under the assumption that the slits are piecewise analytic. We use a completely different idea to solve the problem in its general form.
As the Loewner equation with constant coefficients holds everywhere (and not just almost everywhere), this result generalizes Loewner’s original idea to the multiple-slit case.
Moreover, we consider the following problems:
• The “simple-curve problem” asks which driving functions describe the growth of simple curves (in contrast to curves that touch itself). We discuss necessary and sufficient conditions, generalize a theorem of J. Lind, D. Marshall and S. Rohde to the multiple-slit equation and we give an example of a set of driving functions which generate simple curves because of a certain self-similarity property.
• We discuss properties of driving functions that generate slits which enclose a given angle with the real axis.
• A theorem by O. Roth gives an explicit description of the reachable set of one point in the radial Loewner equation. We prove the analog for the chordal equation.
This study explores novelty choice, a behavioral paradigm for the investigation of visual pattern recognition and learning of the fly Drosophila melanogaster in the flight simulator. Pattern recognition in novelty choice differs significantly from pattern recognition studied by heat conditioning, although both paradigms use the same test. Out of the four pattern parameters that the flies can learn in heat conditioning, novelty choice can be shown for height (horizontal bars differing in height), size and vertical compactness but not for oblique bars oriented at +/- 45°. Upright and inverted Ts [differing in their centers of gravity (CsOG) by 13°] that have been extensively used for heat conditioning experiments, do not elicit novelty choice. In contrast, horizontal bars differing in their CsOG by 13° do elicit novelty choice; so do the Ts after increasing their CsOG difference from 13° to 23°. This indicates that in the Ts the heights of the CsOG are not the only pattern parameters that matter for the novelty choice behavior. The novelty choice and heat conditioning paradigms are further differentiated using the gene rutabaga (rut) coding for a type 1 adenylyl cyclase. This protein had been shown to be involved in memory formation in the heat conditioning paradigm. Novelty choice is not affected by mutations in the rut gene. This is in line with the finding that dopamine, which in olfactory learning is known to regulate Rutabaga via the dopamine receptor Dumb in the mushroom bodies, is dispensable for novelty choice. It is concluded that in novelty choice the Rut cAMP pathway is not involved. Novelty choice requires short term working memory, as has been described in spatial orientation during locomotion. The protein S6KII that has been shown to be involved in visual orientation memory in walking flies is found here to be also required for novelty choice. As in heat conditioning the central complex plays a major role in novelty choice. The S6KII mutant phenotype for height can be rescued in some subsets of the ring neurons of the ellipsoid body. In addition the finding that the ellipsoid body mutants ebo678 and eboKS263 also show a mutant phenotype for height confirm the importance of ellipsoid body for height novelty choice. Interestingly some neurons in the F1 layer of the fan-shaped body are necessary for height novelty choice. Furthermore, different novelty choice phenotypes for different pattern parameters are found with and without mushroom bodies. Mushroom bodies are required in novelty choice for size but they are dispensable for height and vertical compactness. This special circuit requirement for the size parameter in novelty choice is found using various means of interference with mushroom body function during development or adulthood.