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Translation of specific small peptides on the ribosome can confer resistance to macrolide antibiotics. To reveal the molecular details of this and related phenomena, stable RNA-peptide conjugates that mimic peptidyl-tRNA would be desirable, especially for ribosome structural biology. A flexible solid-phase synthesis strategy now allows efficient access to these highly requested derivatives without restriction on the RNA and peptide sequences.

Die Beobachtungen von Neutrinooszillationen belegen, dass Neutrinos sehr kleine, aber von Null verschiene Massen haben. Im Standardmodell der Teilchenphysik werden Neutrinos jedoch als masselos angenommen, da in schwachen Zerfällen und Wirkungsquerschnitten nur linkshändige Neutrinos und rechtshändige Antineutrinos beobachtet werden können. In dieser Masterarbeit wird die Implementierung von Neutrinomassen im Standardmodell mit Hilfe des Seesaw-Mechanismus vom Typ I behandelt. Hierbei werden die Teilchen im Standardmodell durch schwere rechtshändige Neutrinos sowie durch zusätzliche skalare Doubletts erweitert. Nach einer einführenden Diskussion über Dirac-, Majorana-, sowie Hybridmassenterme wird der Seesaw-mechanismus für beliebige Anzahlen von linkshändigen und rechtshändigen Neutrinos, sowie für eine beliebige Anzahl von skalaren Doubletts formuliert. Da im Allgemeinen durch diese Methode nicht alle linkshändigen Neutrinos Masse erhalten, werden anschließend radiative Korrekturen im Rahmen von Einschleifen-Korrekturen zum diskutiert. Im Anschluß an die allgemeine Diskussion von dominanten Einschleifenkorrekturen zum Seesaw-mechanismus werden diese Resultate in zwei verschiedenen Modellen angewendet. Im ersten Modell, welches auf der Standardeichgruppe SU(2)xU(1) basiert, wird die Massenkorretur der linkshändigen Neutrions explizit berechnet, sowie der Spezialfall der minimalen Erweiterung des Standardmodells betrachtet. Im zweiten Modell wird eine zusätzliche exakte Z_2-symmetrie eingeführt, wodurch die Neutrinos ausschließlich durch die Einschleifen-Korrekturen Masse erhalten. In Anschluß an den Spezialfall der minimalen Erweiterung wird auch für dieses Modell eine Verallgemeinerung für beliebige links- und rechtshändige Neutrions sowie für beliebig viele skalare Doubletts formuliert. Insbesondere wird der Zusammenhang zwischen nichtverschwindenden Neutrinomassen und Termen im skalaren Potential hergestellt., The observations of neutrino oscillations verify the existence of small but nonzero neutrino masses. However, in the Standard Model of particle physics neutrinos are assumed massless, since only left-handed neutrinos and right-handed antineutrinos can be observed in weak decays and cross sections. The subject of this master thesis is the implementation of neutrino masses in the Standard Model by means of the seesaw mechanism of type I. The particle content of the Standard Model is being extended by heavy right-handed neutrinos and additional scalar doublets. After a general discussion on Dirac, Majorana and hybrid mass terms, the seesaw mechanism type I is formulated for an arbitrary number of left and right-handed neutrinos and for an arbitrary number of scalar doublets. Since even after this procedure some left-handed neutrinos might remain massless, radiative corrections to the seesaw mechanism, in particular one-loop corrections, are considered. After a general discussion of dominant one-loop corrections to the seesaw mechanism, this knowledge is applied to two different models. In the first model, which is based on the standard gauge group SU(2)xU(1), the mass correction for the left-handed neutrinos is derived explicitly. Afterwards, the special case of a minimal extension within this model is considered. In the second model, the so-called scotogenic model, an additional exact Z_2-symmetry is introduced, which causes the left-handed neutrinos to acquire mass only at one-loop level. After the discussion of the minimal extension, this model is generalized for arbitrary numbers of left and right-handed neutrinos, as well as a scalar doublet. In particular, the correspondence of non-vanishing neutrino masses and terms in the scalar potential is outlined.

Spatial memory refers to the part of the memory system that encodes, stores, recognizes and recalls spatial information about the environment and the agent’s orientation within it. Such information is required to be able to navigate to goal locations, and is vitally important for any embodied agent, or model thereof, for reaching goals in a spatially extended environment. In this paper, a number of computationally implemented cognitive models of spatial memory are reviewed and compared. Three categories of models are considered: symbolic models, neural network models,and models that are part of a systems-level cognitive architecture. Representative models from each category are described and compared in a number of dimensions along which simulation models can differ (level of modeling, types of representation, structural accuracy, generality and abstraction, environment complexity), including their possible mapping to the underlying neural substrate. Neural mappings are rarely explicated in the context of behaviorally validated models, but they could be useful to cognitive modeling research by providing a new approach for investigating a model’s plausibility. Finally, suggested experimental neuroscience methods are described for verifying the biological plausibility of computational cognitive models of spatial memory, and open questions for the field of spatial memory modeling are outlined.

Dietmar Schulte: ‘In the Long Run, Psychotherapy Will Only Be Accepted if It Not Only Can Help but in Fact Does Help’ Prof. Dr. Dietmar Schulte ist einer der fuhrenden Verhaltensthe

Behavioural Group Therapy for Obsessive-Compulsive Disorder Introduction: The effectiveness of a behavioural group therapy programme over 10 double sessions for patients with obsessive-compulsive disorder (OCD) is evaluated. This out-patient group treatment programme provides education about OCD, instruction in a cognitive behavioural approach to self-treatment, guided behavioural treatment and additional multiple family groups. The group therapy (GRU) is compared with a pure medical treatment (MED) and a combined treatment (GRU/MED). Patients and Methods: For evaluation 155 patients (GRU: 45; MED: 55; GRU/MED: 5) were investigated pre (t1) and post (t2) treatment. The groups did not differ significantly pre-treatment regarding Y-BOCS scores and the duration of disorder. The groups differed according to age, depressive symptoms (Beck Depression Inventory) and psychosocial disability regarding work. Results: All groups showed a significant improvement of clinical pathology (Y-BOCS t1: 25.8 ± 4.9; t2 19,3 ± 7,8; p Discussion: Results show that behavioural group therapy with multiple family groups is an effective therapy option for patients with OCD.

The images for Figs ​Figs33–6 are incorrectly switched. The image that appears as Fig 3 should be Fig 5. The image that appears as Fig 4 should be Fig 3. The image that appears as Fig 5 should be Fig 6. The image that appears as Fig 6 should be Fig 4. The figure captions appear in the correct order. Please see the correct figures below. Fig 3 Predicted and recorded place fields in environment B. Fig 4 Neuronal implementation of Bayesian inference based on coincidence detection. Fig 5 Density of place cell spikes, and predicted uncertainty, on a circular track with objects. Fig 6 Place field sizes, and predicted uncertainty, on a circular track with objects, using the extended model.

Spatial memory refers to the part of the memory system that encodes, stores, recognizes and recalls spatial information about the environment and the agent's orientation within it. Such information is required to be able to navigate to goal locations, and is vitally important for any embodied agent, or model thereof, for reaching goals in a spatially extended environment. In this paper, a number of computationally implemented cognitive models of spatial memory are reviewed and compared. Three categories of models are considered: symbolic models, neural network models, and models that are part of a systems-level cognitive architecture. Representative models from each category are described and compared in a number of dimensions along which simulation models can differ (level of modeling, types of representation, structural accuracy, generality and abstraction, environment complexity), including their possible mapping to the underlying neural substrate. Neural mappings are rarely explicated in the context of behaviorally validated models, but they could be useful to cognitive modeling research by providing a new approach for investigating a model's plausibility. Finally, suggested experimental neuroscience methods are described for verifying the biological plausibility of computational cognitive models of spatial memory, and open questions for the field of spatial memory modeling are outlined.

Stop codon recognition is a crucial event during translation termination and is performed by class I release factors (RF1 and RF2 in bacterial cells). Recent crystal structures showed that stop codon recognition is achieved mainly through a network of hydrogen bonds and stacking interactions between the stop codon and conserved residues in domain II of RF1/RF2. Additionally, previous studies suggested that recognition of stop codons is coupled to proper positioning of RF1 on the ribosome, which is essential for triggering peptide release. In this study we mutated four conserved residues in Escherichia coli RF1 (Gln185, Arg186, Thr190, and Thr198) that are proposed to be critical for discriminating stop codons from sense codons. Our thermodynamic and kinetic analysis of these RF1 mutants showed that the mutations inhibited the binding of RF1 to the ribosome. However, the mutations in RF1 did not affect the rate of peptide release, showing that imperfect recognition of the stop codon does not affect the proper positioning of RF1 on the ribosome.

Financial leadership is usually defined as the last in a series of steps, leading from junior accountant to Chief Financial Officer (CFO). Financial leadership means that the CFO performs in a way that leads to a competitive advantage for the organization, not only, but particularly in a financial crisis. In a qualitative study, Austrian CFOs were interviewed between the beginning of the financial crisis in 2007 and 2010. The task was to find out whether there is a change in the challenges for the position of the CFO and which competencies and traits prove to be important and necessary for developing financial leadership competencies. The analysis of the interviews provides some surprising insights into a changing professional profile.

This paper and the underlying research looks at the needs and motives of Chief Executive Officers (CEOs) in Europe and the United States. The first objective of this study is to gain insight into the personality of CEOs and to better understand the motives that drive their behaviors. The second objective is a comparison between American and European leadership styles at the top management level. In order to measure the motives of CEOs, David G. Winter’s “motive imagery”, a method of measuring personality, will be applied. The findings will provide information about the dominant motives of American and European CEOs and contribute to a better understanding of the behavioral aspects of corporate leadership.

In this paper we present the results of an empirical study about Financial Leadership. A questionnaire with 17 questions in 6 categories were de-veloped and sent to 4069 SMEs in the producing sector in Austria. The questionnaire was answered by 318 companies. With the data we wanted to find out if Financial Leadership can prevent companies from suffering a company-crisis or can help companies to overcome a company crisis.

Human spatial representations are known to be remarkablyrobust and efficient, and to be structured hierarchically. Inthis paper, we describe a biologically inspired computationalmodel of spatial working memory attempting to account forthese properties, based on the LIDA cognitive architecture. Wealso present preliminary results regarding a virtual reality experiment,which the model is able to account for, and the quantitativeproperties of the representation.

Das Ziel der vorliegenden Diplomarbeit ist eine Übersicht über verschiedene Typen von Fermat Pseudoprimzahlen zu geben. Die Wahl dieses Themas gründet sich in seiner großen Bedeutung im Bereich der Kryptographie beziehungsweise der Primzahltestung. Weiters finden sich in der Standardliteratur über Zahlentheorie und Kryptographie nur selten ausführliche Informationen zu diesen speziellen Zahlen, denn sie werden meist in Werken über computergestützte Zahlentheorie und Kryptographie erläutert, wobei hierbei das Augenmerk hauptsächlich auf die Algorithmen und Effizienz der Primzahltests gelegt wird. Im Rahmen dieser Arbeit werden Poulet-Zahlen, Fermatsche Pseudoprimzahlen, Carmichael-Zahlen, Eulersche Pseudoprimzahlen, starke Pseudoprimzahlen sowie Superpseudoprimzahlen im abstrakteren und theoretischeren Kontext in Hinblick auf Definition, Eigenschaften und Verteilung besprochen., The purpose of the Diploma thesis at hand is to provide a proper compendium on different types of Fermat pseudoprimes. The choice of this topic is motivated by its great significance in cryptography or more precisely in primality testing. Furthermore, standard literature in number theory and cryptography seldom deals extensively with numbers of that kind and they are usually examined in texts concerning computational number theory or cryptography, in which the main focus is on algorithms and efficiency of primality testing. Within the scope of this work Poulet numbers, Fermat pseudoprimes, Carmichael numbers, Euler pseudoprimes, strong pseudoprimes as well as superpseudoprimes are discussed in a more abstract and theoretic way in terms of definition, properties and distribution.

We present a protocol for the reliable synthesis of non-hydrolyzable 3'-peptidyl-tRNAs that contain all the respective genuine nucleoside modifications. The approach is exemplified by tRNA(Val)-3'-NH-VFLVM-NH(2) and relies on commercially available Escherichia coli tRNA(Val). This tRNA was cleaved site-specifically within the TΨC loop using a 10-23 type DNA enzyme to obtain a 58 nt tRNA 5'-fragment which contained the modifications. After cleavage of the 2',3'-cyclophosphate moiety from the 5'-fragment, it was ligated to the 18 nt RNA-pentapeptide conjugate which had been chemically synthesized. By this methodology, tRNA(Val)-3'-NH-VFLVM-NH(2) is accessible in efficient manner. Furthermore, we point out that the approach is applicable to other types of tRNA.

We present a protocol for the reliable synthesis of non-hydrolyzable 3'-peptidyl-tRNAs that contain all the respective genuine nucleoside modifications. The approach is exemplified by tRNA(Val)-3'-NH-VFLVM-NH(2) and relies on commercially available Escherichia coli tRNA(Val). This tRNA was cleaved site-specifically within the TΨC loop using a 10-23 type DNA enzyme to obtain a 58 nt tRNA 5'-fragment which contained the modifications. After cleavage of the 2',3'-cyclophosphate moiety from the 5'-fragment, it was ligated to the 18 nt RNA-pentapeptide conjugate which had been chemically synthesized. By this methodology, tRNA(Val)-3'-NH-VFLVM-NH(2) is accessible in efficient manner. Furthermore, we point out that the approach is applicable to other types of tRNA.

A qualitative study was the basis for the design of an academic post-graduate program geared to the education of CFOs. A later quantitative survey stimulated refinements of the program. The findings of the studies were directly incorporated into the program. The paper gives an overview of the studies’ conclusions and gives clues on how to integrate them into post-graduate financial management programs.

The role of the Chief Financial Officer (CFO) as a Financial Leader encompasses much more than the mere mastery of the financial issues of an organization. The personality and the leadership style of CFOs have gained little attention so far although the need for a better understanding of behavioral aspects of Financial Leadership clearly exists. This paper and the underlying research attempt to fill this gap by measuring the motives and personalities of Austrian CFOs. Pioneering work on measuring personality has been done by David McClelland, who identified three human motives including power, achievement, and affiliation-intimacy. In order to measure these three motives, David G. Winter developed "motive imagery", a method of measuring content for the above mentioned motives. It is therefore the purpose of this paper to gain insight into the motivation and personality of Austrian CFOs by analyzing 31 interviews with Austrian CFOs. The findings will provide information about the dominant motives of Austrian CFOs and contribute to a better understanding of the behavioral aspects of Financial Leadership.

Metal ions are the salt in the soup of essentially every biological system. Also in the ribosome, the largest natural ribozyme that produces all proteins in every living cell, metal ions have been found contributing significantly to the highly dynamic and accurate process of translation. The ribosome is considered a molecular fossil of the 'RNA world' and it could be shown that the evolutionarily oldest parts of the particle, which build the catalytic center and surrounding domains, are densely packed with divalent metal ions. Nevertheless, metal ions do not seem to directly participate in ribosomal catalysis, their important roles in the ribosome, however, cannot be denied. It is probable that mono- and divalent metal ions primarily promote the functionally competent architecture of the ribosomal RNAs, but more direct roles in mRNA decoding and reading frame maintenance are likely. Decades of biochemical studies and the recent high resolution crystallographic structures of the ribosome strongly indicate that metal ions are involved in essentially every phase of the ribosomal elongation cycle, thus contributing significantly to the precise translation of the genetic code.

Metal ions are the salt in the soup of essentially every biological system. Also in the ribosome, the largest natural ribozyme that produces all proteins in every living cell, metal ions have been found contributing significantly to the highly dynamic and accurate process of translation. The ribosome is considered a molecular fossil of the ‘RNA world’ and it could be shown that the evolutionarily oldest parts of the particle, which build the catalytic center and surrounding domains, are densely packed with divalent metal ions. Nevertheless, metal ions do not seem to directly participate in ribosomal catalysis, their important roles in the ribosome, however, cannot be denied. It is probable that mono- and divalent metal ions primarily promote the functionally competent architecture of the ribosomal RNAs, but more direct roles in mRNA decoding and reading frame maintenance are likely. Decades of biochemical studies and the recent high resolution crystallographic structures of the ribosome strongly indicate that metal ions are involved in essentially every phase of the ribosomal elongation cycle, thus contributing significantly to the precise translation of the genetic code.

Die Finanz- und Wirtschaftskrise hält seit vier Jahren die ganze Welt in Atem. Ausgehend vom Platzen der Immobilienblase in den Vereinigten Staaten von Amerika und des finanziellen Kollaps einiger bedeutender Großbanken begann ein Abwärtstrend der globalen Wirtschaft und der Zusammenbruch des internationalen Finanzmarktes. Dieser ließ ab 2010 auch europäische Staaten in die Nähe eines Staatsbankrotts schlittern und bedroht heute die Stabilität des gesamten Euroraums, sowie der EU-Gemeinschaftswährung. Die vorliegende Arbeit zeigt die Anfänge und Ursachen der bestehenden Krise auf und analysiert ihre Besonderheiten. Der Fokus der Arbeit liegt dabei auf der Frage, wodurch sich die Krisensituation besonders im Euroraum auszeichnet, inwiefern sie sich von vergangenen Krisen unterscheidet und warum die derzeitige Krise die Schaffung eines neuen Europäischen Stabilisierungsmechanismus zur Verbesserung des Krisenmanagements notwendig macht. Anhand der Darstellung der Krisenchronologie werden wichtige Grundbegriffe wie Staatsverschuldung und Staatsbankrott erklärt und mit zentralen wirtschaftstheoretischen Schulen in Verbindung gesetzt. Zum besseren Verständnis illustrieren historische Beispiele die jeweiligen Besonderheiten. Zudem wird der Fokus auf Ratingagenturen gelegt, deren historische Entstehungsgeschichte, sowie Arbeitsweise und Einfluss in der Krise aufgezeigt werden. Anhand des Beispiels Griechenlands wird die Lage in Europa dargestellt und politische wie rechtliche Schwächen innerhalb der Union herausgearbeitet sowie die gemeinschaftlichen Gegenmaßnahmen beschrieben. Abschließend wird ein Blick in die Zukunft gewagt und mögliche Szenarien, wie der etwaige Austritt eines Staates aus der Währungsgemeinschaft, imaginiert.

This book will help researchers and engineers in the design of ethical systems for robots, addressing the philosophical questions that arise and exploring modern applications such as assistive robots and self-driving cars. The contributing authors are among the leading academic and industrial researchers on this topic, and the book will be of value to researchers, graduate students, and practitioners engaged with robot design, artificial intelligence, and ethics.

Platelets are known to be part of haemostasis but they are also players in innate host defense. Recently, we observed that platelets attenuate the virulence of Aspergillus spp. in vitro. However, little is known about the antifungal effects of platelets in the presence of antimycotics against non-A. fumigatus Aspergillus species. We therefore investigated whether platelets increase the in vitro activity of amphotericin B, voriconazole, posaconazole and caspofungin against two clinical isolates each of Aspergillus fl avus, Aspergillus terreus and Aspergillus niger. The antifungal activity was evaluated by assessing germination percentages, hyphal elongation and hyphal damage by use of XTT. The combination of platelets plus amphotericin B signifi cantly ( P 0.05) enhanced the reduction of germination percentage compared to either substance alone. Among triazoles, voriconazole exhibited signifi cant effects with platelets for all tested aspergilli. Overall, these fi ndings suggest that among the tested antimycotic substances, amphotericin B in combination with platelets has enhancing effects in reducing germination and hyphal elongation in the tested nonA. fumigatus Aspergillus species. These data indicate that platelets act benefi cially with antimycotics in an early stage of fungal growth by blocking and/or delaying fungal germination and hyphal elongation; both crucial mechanisms in the development of invasive fungal disease.

Der Vortrag "Cosmic Rays - Energy Spectrum and Acceleration Mechanisms" wurde am 14.6.2010 im Seminar 280193 SE Astronomisches Bachelorseminar gehalten.

Sir, Invasive aspergillosis is increasingly recognized in immunocompromised hosts. Patients with prolonged and deep granulocytopenia following chemotherapy for haemato-oncological disorders or allogeneic bone marrow transplant recipients are particularly at risk. Platelets are second in abundance to red blood cells in the circulation, with 1.5–4.0×10 platelets/mL of blood in healthy individuals. They are essential components in haemostasis, but they also play an important role in antimicrobial host defence. Recently, we observed that platelets released serotonin after contact with aspergilli. Furthermore, platelets attenuated the virulence of Aspergillus spp. as the cell wall compound galactomannan was significantly decreased. Several in vitro studies have indicated that immune effector cells in combination with antifungals exert synergistic effects on aspergilli. However, no data are available on the effects of platelets and antimycotics on aspergilli. Two clinical Aspergillus fumigatus isolates and four antifungal agents were studied: amphotericin B (Sigma–Aldrich, Vienna, Austria); voriconazole (kindly provided by Pfizer, Vienna, Austria); posaconazole (kindly provided by Schering-Plough Research Institute, Kenilworth, NJ, USA); and caspofungin (MSD, Vienna, Austria). The MICs of all drugs used in this study were 0.5 mg/L for both isolates. Based on the MICs, drug concentrations of 0.5 and 1 mg/L were used for the platelet/drug studies. Fresh platelets were provided from the local Department of Immunology and Blood Transfusion. Platelets were collected from healthy donors by thrombocytopheresis using an Amicus cell separator (Baxter, Vienna, Austria). One hundred microlitres each of platelets (1×10/mL) and conidia (1×10/mL) in an effector/target ratio of 100:1 and specific concentrations of antifungals (0.5 and 1 mg/L) were inoculated into microwell plates (Greiner, Vienna, Austria) and incubated at 378C. The morphology of the A. fumigatus strains treated either with the combination of platelets plus antifungals or with each substance or platelets alone was investigated by assessing the germination rate and hyphal elongation, as described previously. Hyphal damage was assessed by a colorimetric assay with the dye 2,3-bis[2-methoxy-4-nitro-5-sulphophenyl]-2-H-tetrazolium-5carboxynilide sodium salt (XTT; Sigma–Aldrich) plus 40 mg/mL coenzyme Q (Sigma–Aldrich) and antifungal activity was calculated as the percentage of hyphal damage. Each experiment was performed with platelets from one donor using duplicate or quadruplicate wells for each condition and strain, and repeated six times. Differences between mean values of both strains were statistically evaluated by repeated-measures analysis of variance followed by Dunnett’s correction for multiple comparisons. A twosided P value of ,0.05 indicated statistical significance. Human platelets plus amphotericin B achieved significantly greater inhibition of the germination rate (P,0.05) than did amphotericin B or platelets alone (Figure 1a). The effect was additive. These results were found with both tested amphotericin B concentrations, although 1 mg/L revealed a better inhibitory effect than the lower concentration (Figure 1a). With caspofungin, the germination rate was not significantly reduced (Figure 1b). When azoles were used in combination with platelets, the inhibitory effect was found to be additive in comparison with either azole or platelets alone (Figure 1c and d). As found for the germination rate, human platelets plus amphotericin B achieved significantly greater inhibition of hyphal elongation (P,0.05) than amphotericin B or platelets alone. Hyphal elongation was significantly reduced in all tested aspergilli, either under platelet or caspofungin treatment. When used in combination, the effect was found to be additive. The combination of platelets plus either azole at any concentration tested did not significantly enhance the reduction of hyphal elongation. Platelets decreased the ability of hyphae to reduce XTT; however, the combination of platelets plus antimycotics had no additive effect on hyphal damage (data not shown). Our findings indicate that platelets in combination with antimycotics exert additive effects in reducing the germination rate and hyphal elongation of A. fumigatus in vitro. Among the tested antimycotic substances, amphotericin B revealed the best results in combination with human platelets. However, platelets plus antimycotics were not additive for hyphal damage. In the immunocompromised patient, inhaled Aspergillus conidia germinate into hyphae, the growing and invading structures of filamentous fungi. Consequently, blocking fungal germination and delaying hyphal growth is crucial in preventing invasive disease. In our study, the combination of platelets plus amphotericin B synergistically enhanced the antifungal activity (P,0.05) in reducing germination rate and hyphal elongation. Amphotericin B is known to complex with sterols in the fungal cell membrane, leading to pore formation and

This paper discusses a framework for processing agent based pedestrian activity simulations within a shopping environment. A pedestrian multi-agent model will be in-troduced that is the base of pedestrian movement simulation. In this paper, the focus is on this simulation.