Untersuchungen zu Polyketidsynthasen aus Dictyostelium discoideum

Der in der vorliegenden Arbeit untersuchte Organismus Dictyostelium discoideum ist eine ubiquitär vorkommende Amöbe mit der Fähigkeit bei Nahrungsmangel in einen vielzelligen Fruchtkörper zu differenzieren. Bei der Sequenzierung des Genoms wurden 40 funktionale Gene für Polyketidsynthasen (PKS) beschrieben. Damit einhergehend wird ein großes Potential für die Biosynthese von Polyketiden vermutet, welches die bisher in D. discoideum beschriebenen Naturstoffe weit übersteigt. Der OSMAC-Ansatz (one strain-many compounds) wurde herangezogen um die Biosynthese von Sekundärmetaboliten zu aktivieren. Dabei wurden unter Verwendung verschiedener Extraktionsmittel mittels HPLC-DAD keine aktivierenden Bedingungen identifiziert. Unter Verwendung von RT-qPCR wurde pks26 als entwicklungs- und cAMP-abhängig exprimiertes Gen identifiziert. Um das PKS26-Biosyntheseprodukt zu identifizieren, wurden mittels homologer Rekombination Knock-Out- sowie Genaktivierungsstämme erzeugt. Ein Vergleich der Gesamtkultur-Extrakte von Wildtyp, Knock-Out- und Genaktivierungs-stamm mittels UHPLC-ESI-HRAM/MS und anschließender Hauptkomponentenanalyse des Gesamtmetaboloms führte zur Identifikation von 21 Kandidaten für das Biosyntheseprodukt von PKS26. Im Cheating-Assay wurde das Verhalten der pks26-Mutanten während der chimären multizellulären Entwicklung untersucht. Der publizierte Loser-Phänotyp der pks26-REMI-Mutante (restriction enzyme-mediated integration) konnte nicht bestätigt werden. Während der klonalen multizellulären Entwicklung verhielten sich die pks26-Mutanten wie ihr Elternstamm und zeigten in verschiedenen Fitnesstests keine Auffälligkeiten

Electric field controlled flow behaviour of electrorheological fluid

The main purpose of the present study is to demonstrate the electric field controlled flow behaviour of electrorheological (ER) fluid. We have investigated the relation between the electric field and the change in the viscosity of electrorheological fluids. Different kinds of suspensions are used to search for the proper combination ER fluid for applying in a motor mount. A rotational viscometer is used to get how the viscosity depends on temperature and a special device to measure the effect of electric fields up to 1.8 kVmm-1

Development of a framework to guide research into policies promoting physical activity and healthy diets in the European context: the system-based Policy Evaluation Network (PEN) framework

Background The Policy Evaluation Network (PEN) is a multidisciplinary Pan-European research consortium focussing on policies affecting dietary intake, physical activity and sedentary behaviour. At the start, the PEN consortium expressed the need for an overarching, system-based framework covering the complexities between the different domains of the policy process (design, implementation and outcomes) in order to execute all research activities in a coherent way. This article describes the PEN framework itself and its development process. Methods A staged approach to the development of a system-based framework was executed between February 2019 and February 2022. We started with a point-of-departure framework, made use of existing models, collected PEN outputs at different project stages (through online meetings, e-mail exchanges and workshops with PEN researchers) and drew updated versions of the framework, which resulted in the system-based PEN framework. Results The system-based PEN framework depicts the policy process as a complex system, visualizing the dynamic interrelations between and within policy domains (i.e. policy design, policy implementation and policy outcomes), the ways they interact with the context, and how to assure a focus on equity in each domain. Conclusions The system-based PEN framework may guide researchers and professionals involved in the evaluation of health- or sustainability-related policies to consider their evaluation in a comprehensive picture, including domain interactions, contextual influences and equity considerations, as these can have important implications for the scope of their research. The stage-based process as applied for the development of the PEN framework can serve as a template for other research projects wishing to develop their own framework

Digitálisan szabályozott gépészeti rendszerek dinamikája = Dynamics of digitally controlled mechanical systems

A kutatási projektben digitálisan szabályozott mérnöki szerkezet stabilitásvizsgálatával foglalkoztunk figyelembe véve a szabályozás visszacsatolásának időkésését. A kutatási projektben a következő témákkal foglalkoztunk: - Dinamikai rendszerek szabályozása időkésést tartalmazó visszacsatolás esetén a beavatkozom-és-várok szabályozási elv felhasználásával. - Szerszámgéprezgések stabilitásvizsgálata marási és esztergálási folyamatok során. - Torziós rezgések csillapítása gépjárműveknél elektroreológiai folyadékokkal. - Egyensúlyozás reflexkéséssel gyorsulásérzékelővel történő szögpozíció meghatározás esetén illetve paraméteres gerjesztés esetén. - A szemi-diszkretizációs numerikus módszer fejlesztése késleltetett dinamikai rendszerek stabilitásvizsgálatára. A kutatás eredményeként 33 publikáció született, köztük egy angol nyelvű könyv a Springer kiadásában, egy PhD értekezés, 14 folyóiratcikk (Össz. impakt faktor = 16,9) valamint egy MTA doktori értekezés is benyújtásra kerül. | Within the frame of the research project, we investigated the stability properties of engineering systems subjected to digital control with special attention to the time delay in the feedback loop. The following topics were included into the research: - Control of dynamic systems with feedback delay using the act-and-wait control concept. - Stability analysis of machine tool chatter with applications to turning and milling processes. - Damping of torsional vibrations in vehicles using electro-rheological fluids. - Balancing with reflex delay in the case when of angular position is measured by accelerometer, and in the case of parametric excitation. - Development of the semi-discretization numerical technique to the stability analysis of delayed systems. As a result of the research project, 33 publications were published, including a book pressed by Springer, a PhD thesis, 14 journal articles (Sum impact factor = 16,9) and a dissertation for the title Doctor of the Hungarian Academy of Sciences were also submitted

Uptake and absorption of fluoranthene from spiked microplastics into the digestive gland tissues of blue mussels, Mytilus edulis L.

The present work intended to investigate the fate of contaminant-loaded microplastics if ingested by benthic filter feeder Mytilus edulis under laboratory conditions. In the course of a 7-day experiment the mussels were exposed to PVC microplastics in a size range >40 mm, in doses of 2000 particles L_1 (11.56 mg L_1). Particles were either virgin or loaded with one of four different nominal concentrations of the polycyclic aromatic hydrocarbon (PAH) fluoranthene (500, 125, 31.25 and 7.8125 mg g_1). Verification of fluoranthene concentrations on the particles provided evidence of the high absorptive capacity of PVC for this PAH, indicating that comparable particles may serve as considerable accumulation sites for high concentrations of hydrophobic contaminants in the aquatic environment. Analysis of digestive gland tissues via polarised light microscopy revealed the occurrence of particles and particle aggregates within stomach and intestines of all mussels treated with microplastics, thus making the xenobiotic bioavailable. Results of contaminant analysis in mussel tissues via equilibrium sampling point to a considerable capability of microplastics for the accumulation of hydrophobic contaminants from the environment and their potential to act as vehicles for the transport of theses contaminants into organismal tissues. of fluoranthene concentrations on the particles provided evidence of the high absorptive capacity of PVC for this PAH, indicating that comparable particles may serve as considerable accumulation sites for high concentrations of hydrophobic contaminants in the aquatic environment. Analysis of digestive gland tissues via polarised light microscopy revealed the occurrence of particles and particle aggregates within stomach and intestines of all mussels treated with microplastics, thus making the xenobiotic bioavailable. Results of contaminant analysis in mussel tissues via equilibrium sampling point to a considerable capability of microplastics for the accumulation of hydrophobic contaminants from the environment and their potential to act as vehicles for the transport of theses contaminants into organismal tissues. © 2021 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY licens

Risk Prediction Scores for Postoperative Mortality After Esophagectomy: Validation of Different Models

Background: Different prediction models for operative mortality after esophagectomy have been developed. The aim of this study is to independently validate prediction models from Philadelphia, Rotterdam, Munich, and the ASA. Methods: The scores were validated using logistic regression models in two cohorts of patients undergoing esophagectomy for cancer from Switzerland (n = 170) and Australia (n = 176). Results: All scores except ASA were significantly higher in the Australian cohort. There was no significant difference in 30-day mortality or in-hospital death between groups. The Philadelphia and Rotterdam scores had a significant predictive value for 30-day mortality (p = 0.001) and in-hospital death (p = 0.003) in the pooled cohort, but only the Philadelphia score had a significant prediction value for 30-day mortality in both cohorts. Neither score showed any predictive value for in-hospital death in Australians but were highly significant in the Swiss cohort. ASA showed only a significant predictive value for 30-day mortality in the Swiss. For in-hospital death, ASA was a significant predictor in the pooled and Swiss cohorts. The Munich score did not have any significant predictive value whatsoever. Conclusion: None of the scores can be applied generally. A better overall predictive score or specific prediction scores for each country should be develope

Development of a framework to guide research into policies promoting physical activity and healthy diets in the European context: the system-based Policy Evaluation Network (PEN) framework

BACKGROUND: The Policy Evaluation Network (PEN) is a multidisciplinary Pan-European research consortium focussing on policies affecting dietary intake, physical activity and sedentary behaviour. At the start, the PEN consortium expressed the need for an overarching, system-based framework covering the complexities between the different domains of the policy process (design, implementation and outcomes) in order to execute all research activities in a coherent way. This article describes the PEN framework itself and its development process. METHODS: A staged approach to the development of a system-based framework was executed between February 2019 and February 2022. We started with a point-of-departure framework, made use of existing models, collected PEN outputs at different project stages (through online meetings, e-mail exchanges and workshops with PEN researchers) and drew updated versions of the framework, which resulted in the system-based PEN framework. RESULTS: The system-based PEN framework depicts the policy process as a complex system, visualizing the dynamic interrelations between and within policy domains (i.e. policy design, policy implementation and policy outcomes), the ways they interact with the context, and how to assure a focus on equity in each domain. CONCLUSIONS: The system-based PEN framework may guide researchers and professionals involved in the evaluation of health- or sustainability-related policies to consider their evaluation in a comprehensive picture, including domain interactions, contextual influences and equity considerations, as these can have important implications for the scope of their research. The stage-based process as applied for the development of the PEN framework can serve as a template for other research projects wishing to develop their own framework

Using GRADE Evidence to Decision frameworks to support the process of health policy-making

BACKGROUND: Grading of Recommendations, Assessment, Development and Evaluation (GRADE) Evidence to Decision (EtD) frameworks are well-known tools that enable guideline panels to structure the process of developing recommendations and making decisions in healthcare and public health. To date, they have not regularly been used for health policy-making. This article aims to illustrate the application of the GRADE EtD frameworks in the process of nutrition-related policy-making for a European country. METHODS: Based on methodological guidance by the GRADE Working Group and the findings of our recently published scoping review, we illustrate the process of moving from evidence to recommendations, by applying the EtD frameworks to a fictitious example. Sugar-sweetened beverage (SSB) taxation based on energy density was chosen as an example application. RESULTS: A fictitious guideline panel was convened by a national nutrition association to develop a population-level recommendation on SSB taxation aiming to reduce the burden of overweight and obesity. Exemplary evidence was summarized for each EtD criterion and conclusions were drawn based on all judgements made in relation to each criterion. As a result of the high priority to reduce the burden of obesity and because of the moderate desirable effects on health outcomes, but considering scarce or varying research evidence for other EtD criteria, the panel made a conditional recommendation for SSB taxation. Decision-makers may opt for conducting a pilot study prior to implementing the policy on a national level. CONCLUSIONS: GRADE EtD frameworks can be used by guideline panels to make the process of developing recommendations in the field of health policy more systematic, transparent and comprehensible

Development of a framework to guide research into policies promoting physical activity and healthy diets in the European context: the system-based Policy Evaluation Network (PEN) framework

BACKGROUND: The Policy Evaluation Network (PEN) is a multidisciplinary Pan-European research consortium focussing on policies affecting dietary intake, physical activity and sedentary behaviour. At the start, the PEN consortium expressed the need for an overarching, system-based framework covering the complexities between the different domains of the policy process (design, implementation and outcomes) in order to execute all research activities in a coherent way. This article describes the PEN framework itself and its development process. METHODS: A staged approach to the development of a system-based framework was executed between February 2019 and February 2022. We started with a point-of-departure framework, made use of existing models, collected PEN outputs at different project stages (through online meetings, e-mail exchanges and workshops with PEN researchers) and drew updated versions of the framework, which resulted in the system-based PEN framework. RESULTS: The system-based PEN framework depicts the policy process as a complex system, visualizing the dynamic interrelations between and within policy domains (i.e. policy design, policy implementation and policy outcomes), the ways they interact with the context, and how to assure a focus on equity in each domain. CONCLUSIONS: The system-based PEN framework may guide researchers and professionals involved in the evaluation of health- or sustainability-related policies to consider their evaluation in a comprehensive picture, including domain interactions, contextual influences and equity considerations, as these can have important implications for the scope of their research. The stage-based process as applied for the development of the PEN framework can serve as a template for other research projects wishing to develop their own framework