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Amtliche Bekanntmachungen, 55. Jahrgang, Nr. 90
No full textÄnderung und zugleich Neubekanntmachung der Ordnung für die Wahl zum Fakultätsrat der Philosophischen Fakultät der Rheinischen Friedrich-Wilhelms-Universität Bonn vom 5. November 202
Entwicklung der Wirkstoffzusammensetzung von Händedesinfektionsmitteln in Deutschland von 2004 bis 2022 unter besonderer Berücksichtigung von Ethanol
Get PDFZielsetzung: Analysiert wurde die Anzahl der in Händedesinfektionsmitteln (HD) eingesetzten Wirkstoffe in Deutschland anhand der Desinfektionsmittel-Listen des Verbunds für Angewandte Hygiene (VAH) der Jahre 2004, 2012 und 2022, um die Entwicklung in Bezug auf den Einsatz nicht erforderlicher bzw. kritischer Wirkstoffe in alkoholbasierten Händedesinfektionsmittel (ABHR) zu bewerten.
Ergebnisse: Während im Jahr 2004 in den HD (97 gelistete HD) 20 unterschiedliche Wirkstoffe eingesetzt wurden, waren es in den Jahren 2012 (201 gelistete HD) nur noch 14 und 2024 (332 gelistete HD) 15 unterschiedliche Wirkstoffe. Nicht mehr eingesetzt werden als Zusatz zu ABHR Benzoesäure, Clorocresol, Clorofen, Octenidindihydrochlorid, Peressigsäure, Polihexanid und Triclosan. Gleichzeitig sank die Anzahl der Wirkstoffe pro Produkt. Im Zeitraum 2002 bis 2022 zeigte sich eine Zunahme ABHR, so dass 2022 nur noch vier HD keinen Alkohol enthielten, drei auf Basis von PVP-Iod, eins auf Basis von quartären Ammoniumverbindungen. Während 2-Propanol 2004 und 2022 noch als erstgenannter Wirkstoff dominierte, wurden 2022 hauptsächlich ABHR mit Ethanol als erstgenanntem Wirkstoff zertifiziert. Der prozentuale Anteil von Ethanol in ABHR ist gemessen an allen VAH gelisteten Produkten sowie als Hauptwirkstoff von 2004 bis 2022 um 43,4% gestiegen. Parallel ist ein Rückgang bei ABHR mit der Wirkstoffbasis 2-Propanol um 33,2% zu verzeichnen.
Diskussion: Die Abnahme der Gesamtzahl eingesetzter Wirkstoffe dürfte zwei Gründe haben. Durch Zusatz von antiseptischen Wirkstoffen zu ABHR wird deren remanente Wirksamkeit nicht verstärkt. Zugleich sind die den ABHR zugesetzten antiseptischen Wirkstoffe weniger gut verträglich als Alkohole, so dass der Verzicht ethisch sinnvoll ist. Der Anstieg Ethanol basierter ABHR spricht dafür, dass diese von den Anwendern bevorzugt werden. Eine Erklärung dürfte sein, dass 1-Propanol im Unterschied zu Ethanol sowohl für gesunde als auch für atopische Haut irritierend wirken kann.
Schlussfolgerung: Da Ethanol als einziger Wirkstoff mit umfassender Wirksamkeit gegen unbehüllte Viren zur HD eingesetzt werden kann, beide Propanole unphysiologischer für den menschlichen Organismus als Ethanol sind, Ethanol besser hautverträglich ist als 1-Propanol und für Ethanol eine Beeinträchtigung des Hautmikrobiom ausgeschlossen wurde, muss Ethanol als Wirkstoff für ABHR erhalten bleiben. Das ist bei der Diskussion der möglichen Biozideinstufung von Ethanol als CMR unbedingt zu berücksichtigen, zumal eine derartige Einstufung der wissenschaftlichen Grundlage entbehrt
The Effects of Differential Constraints and Surface Energies on Scaling Laws for Singular Perturbation Problems
Get PDFMotivated by mathematical models for phase transformations, arising, for example, in shape-memory alloys, and for micromagnetism in ferromagnetic materials, we study a class of A-free differential inclusions quantitatively. For this reason, we consider singular perturbation models of differential inclusions under an A-free constraint and determine the scaling in the singular perturbation parameter. The focus of this thesis is to characterize the influence of the order of the operator on the possible scaling laws and to show that the model is robust under changes of the surface energy. The first is achieved by establishing lower bounds for the compatible and incompatible two-well problem. It turns out that the scaling is determined by the maximal vanishing order on the sphere of the symbol of the differential operator applied to the compatible direction. These lower bounds are proven to be optimal for the divergence operator and for a higher order generalization of the curl and curl curl operators as an annihilator of symmetrized derivatives. The influence of the surface energy is studied by comparing sharp and diffuse interface models, as well as suitable interpolations of these. We deduce the lower bound for the diffuse model by estimating the energy from below through the sharp interface model and complement them with matching upper bounds for a model class of wells in the case of the curl operator. Furthermore, an N-well setting giving rise to higher order laminates for the curl operator is studied. If the energy penalizes only oscillations in a certain direction, we observe that for almost all directions this anisotropic energy scales like the full isotropic energy. The exceptional directions are those, where the anisotropic energy does not penalize the oscillations of the "inner-most" laminate. The scaling for these matches the ones of a lower order laminate. Furthermore, a non-algebraic scaling law for a divergence-free T3 structure is discussed. This result quantifies the dichotomy between the rigidity of exact solutions and the flexibility of approximate solutions for the associated inclusion
Amtliche Bekanntmachungen, 55. Jahrgang, Nr. 96
No full textOrdnung der Rechts- und Staatswissenschaftlichen Fakultät der Rheinischen Friedrich-Wilhelms-Universität Bonn zur Berechnung der Bachelornote nach § 66 Absatz 1a Satz 8 HG vom 26. November 202
Expanding cryospheric landform inventories : quantitative approaches for underestimated periglacial block- and talus slopes in the Dry Andes of Argentina
Get PDFThere is a clear spatial discrepancy between the area potentially underlain by permafrost and the landforms recorded in the national inventory of cryospheric landforms in the Dry Andes of Argentina (∼22°–35°S). In the periglacial belt around 30°S, these areas are often covered by extensive block- and talus slopes, whose distribution and potential permafrost content have received little attention so far. We present the first geomorphological mapping and predictive modeling of these underestimated landforms in a semi-arid high Andean catchment with representative cryospheric landform cover (30°S, 69°W). Random forest models produce robust and transferable predictions of both target landforms, demonstrating a high predictive power (mean AUROC values ≥0.95 using non-spatial validation and ≥0.83 using spatial validation). By combining geomorphological mapping, predictive modeling, and geostatistical analysis of block- and talus slopes, we enhance our knowledge of their distribution characteristics, formative controls and potential ground ice content. While both landforms provide suitable site conditions for permafrost occurrence, talus slopes are expected to contain significantly higher ground ice content than blockslopes due to their more favorable characteristics for ice formation and preservation. Given their widespread distribution across almost 79% of the modeled area, block- and talus slopes constitute potentially important ground ice storages and runoff contributors that are not included in current hydrological assessments of mountain permafrost. Our results underscore the need to expand existing cryospheric landform inventories to achieve a more comprehensive quantification of underrepresented periglacial landforms and thus a realistic acquisition of cryospheric water resources in high mountain environments. The newly compiled inventories can serve as a basis for further investigations (e.g., geophysical surveys, hydrochemical analysis, permafrost distribution models) at different spatial scales
From Soil Legacy to Wheat Yield Decline : Studying the Plant-Soil Feedback Mechanisms in Wheat Rotations
Get PDFWinter wheat is one of the most important crops cultivated globally. The yield of winter wheat is stagnating in several areas of the world since the 1990s. Continuous winter wheat cultivation is associated with a marked yield decline that is often attributed to the proliferation of the soil-borne pathogen Gaeumannomyces tritici (take-all). However, it is unlikely that this yield decline is solely due to take-all, but rather it is the outcome of more complex soil-microbe-plant interactions that drive plant-soil feedbacks in the rhizosphere of winter wheat. The soil legacy of the preceding crop is a major determinant of the growth and development of the succeeding plant, and it can be expected that the rotational position of winter wheat will influence the productivity of the following winter wheat. The aim of this thesis was to analyze plant-soil feedbacks in successive winter wheat rotations and better understand the observed yield decline. We specifically aimed at investigating how the rotational position of winter wheat affects the microbial communities and the associated nutrient cycling and enzymatic activity in the soil, and how the root system of winter wheat responds to these changes, thereby affecting plant growth and productivity. Finally, we looked into the potential of compost and plant growth-promoting rhizobacteria to compensate for the growth reduction in continuous winter wheat rotations and provide farmers with a sustainable toolbox to safeguard plant productivity and food production. We developed and used novel mesocosms for growing winter wheat and employing isotopic tracers to enable the quantification of important rhizosphere processes and assess above- and belowground carbon allocation, nitrogen uptake and water uptake from various soil layers. We found that there was much higher initial nitrate availability in the soil of winter wheat after oilseed rape at the germination and tillering growth stage compared to continuous winter wheat, especially in the subsoil. This was associated with nitrogen immobilization by the microbial community, which was associated with distinct root plastic responses and reduced winter wheat growth early in the growing season. Soil legacy of the preceding crop also had a strong influence on soil enzymatic activity and nitrogen cycling as indicated by changes in the activity of nitrogen-related enzymes and the abundance of microbial nitrogen-cycling genes. We also found a higher and sustained belowground allocation of freshly assimilated carbon at the flowering and grain ripening growth stages of winter wheat growing after oilseed rape that was available for microbial use, revealing a higher rhizodeposition in non-successive winter wheat rotations. Non-successive winter wheat converted more of the freshly assimilated carbon into biomass and achieved higher yields than continuous winter wheat. Winter wheat after oilseed rape exhibited distinct patterns in shaping its microbial community, with a higher abundance of taxa involved in important nutrient mineralization processes and capable of conferring plant protection against important soil pathogens. Application of both compost and plant growth-promoting rhizobacteria caused a positive plant-soil feedback in continuous winter wheat cultivation, compensating the growth reduction and yield decline. This work thus demonstrated that yield decline in successive winter wheat rotations is dependent on several key rhizosphere processes and that soil legacy of the preceding crop is an important driver of the productivity of the succeeding plant. By understanding this phenomenon, we can design resilient, productive and multifunctional farming systems that can cope with the increasing adversities of climate change without compromising yield production and food security
Retrospektive Analyse nativer Kniegelenksinfektionen : Einfluss klinischer, mikrobiologischer und laborchemischer Faktoren auf den klinischen Verlauf und Therapieerfolg
Get PDFDie Inzidenz des nativen Kniegelenkinfekts steigt in den letzten Jahren stetig ein. Eine schnelle Diagnosesicherung ist notwendig, um schwerwiegende Gelenkdestruktionen, Funktionseinschränkungen oder auch eine Sepsis zu verhindern.
Die Diagnostik beinhaltet neben der Anamnese, die körperliche Untersuchung und die Laborabnahme mit der Abnahme von Blutkulturen. Zusätzlich als Bildgebung wird ein Röntgenbild empfohlen, um eine knöcherne Mitbeteiligung zu beurteilen. Fakultativ kann eine Sonographie durchgeführt werden, um einen Gelenkerguss zu bestimmen. Der Goldstandard in der Diagnostik stellt die Gelenkpunktion mit der Zellzahlbestimmung dar.
Die Therapie wird nach dem Schweregrad mit Hilfe der Gächter Klassifikation eingeleitet. So erfolgt je nach Gächter Stadium eine arthroskopische Spülbehandlung oder offene Revision mit Débridement. Ergänzend folgt eine empirische iv. Antibiotikagabe. Gelingt ein Erregernachweis, kann antibiogrammgerecht die Antibiotikagabe im Verlauf angepasst werden.
Die Diagnose frühzeitig zu stellen, gestaltet sich auch heute noch als besonders schwierig. Es gibt keinen Schritt in der Diagnostik, der die Diagnose eines nativen Kniegelenksinfekts frühzeitig und sicher stellen kann. Lediglich die Gesamtheit aller verschiedener Diagnoseschritte lässt einen Kniegelenksinfekt vermuten und nach und nach sichern.
Mit Hilfe dieser Arbeit konnten Parameter herausgearbeitet werden, die einen Kniegelenkinfekt begünstigen, sowie auch einen komplizierten Krankheitsverlauf vermuten lassen, wie z.B. das weibliche Geschlecht, ein höheres Lebensalter oder auch das Vorkommen von verschiedenen Komorbiditäten. So besteht die Möglichkeit in Zukunft anhand von Risikofaktoren früher einen Kniegelenksinfekt zu vermuten und den erwarteten Schweregrad zu kalkulieren
Rebellionen II : Reaktionen der Charaktere in ausgewählten modernen Sanskrit-Erzählungen auf eine Beeinträchtigung durch traditionelle Normen
Get PDFDiese Studie untersucht, wie Figuren in ausgewählten modernen Sanskrit-Erzählungen auf Beeinträchtigungen durch traditionelle soziale und religiöse Normen reagieren. Die moderne Sanskrit-Kurzepik (laghukathā) ist trotz ihrer großen Textmenge seit dem späten 19. Jahrhundert ein kaum erschlossenes Forschungsfeld; insbesondere Prosa aus der Zeit nach der indischen Unabhängigkeit wurde bisher nur selten literaturwissenschaftlich analysiert. Auf der Grundlage von zehn Erzählungen aus den Jahren 1954 bis 2015, verfasst von Autorinnen und Autoren aus verschiedenen indischen Bundesstaaten, rekonstruiert die Arbeit die Konfliktdynamiken, die entstehen, wenn individuelle Bedürfnisse mit tradierten Normen familialer Autorität, arrangierter Ehe, Ritualen und sozialer Kontrolle kollidieren.
Methodisch rückt die Untersuchung die Perspektive der literarischen Figuren in den Mittelpunkt und verbindet textnahe Analyse mit einem interdisziplinären Zugriff auf anthropologische, rechtshistorische und soziologische Quellen. "Erfundene Traditionen" im Sinne Hobsbawms werden ebenso berücksichtigt wie die Frage nach der Welthaltigkeit der Erzählungen, die durch externe Datensätze überprüfbar gemacht wird.
Die Ergebnisse zeigen, dass Rebellion in diesen Erzählungen überwiegend als alltagspraktische, individuell angepasste Strategie erscheint, als Widerstand gegen konkrete Akteurinnen und Akteure innerhalb traditioneller Strukturen. Reaktionen reichen von Kompromissbildung und emotionalem Rückzug bis hin zu Flucht, Individualisierung und punktueller Auflehnung. Die Rebellionen sind komplex ausgestaltet und in den Narrationen häufig erfolgreich. Die Studie demonstriert, dass moderne Sanskrit-Kurzepik ein bedeutendes, bisher unterschätztes Korpus für die Erforschung sozialer Normenkonflikte, individueller Handlungsspielräume und kultureller Wandelprozesse im modernen Indien darstellt.This study examines how characters in selected modern Sanskrit short stories respond to restrictions caused by traditional social and religious norms. Despite its considerable volume since the late nineteenth century, modern Sanskrit short fiction (laghukathā) remains a largely unexplored field; prose written after Indian independence has received particularly little scholarly attention. Drawing on ten stories composed between 1954 and 2015 by authors from various Indian states, the study reconstructs the dynamics of conflict that arise when individual needs collide with traditional norms surrounding familial authority, arranged marriage, ritual obligations, and mechanisms of social control.
Methodologically, the analysis centers the perspectives of the literary characters and combines close reading with an interdisciplinary engagement with anthropological, legal-historical, and sociological sources. "Invented traditions" in Hobsbawm's sense are taken into account, as is the question of the narratives' embeddedness in verifiable social realities, assessed through external datasets.
The findings demonstrate that rebellion in these stories appears predominantly as an everyday, individually calibrated strategy—resistance directed not at the system as a whole but at specific actors within traditional structures. Responses range from compromise formation and emotional withdrawal to flight, individualization, and targeted acts of defiance. The rebellions are complex in form and mostly successful within the narrative frameworks. The study shows that modern Sanskrit short fiction constitutes a significant yet understudied corpus for investigating conflicts surrounding social norms, individual agency, and processes of cultural transformation in modern India.अस्मिन् प्रबन्धे आधुनिकसंस्कृतलघुकथासु चयनितचरितानां पारम्परिक-सामाजिक-धार्मिक-नियमैः जन्येषु अवरोधेषु कथं प्रतिसादः दत्तः इति परीक्ष्यते। उन्नविंशतितमशताब्दस्य उत्तरार्धात् आरभ्य विस्तीर्णं स्यात् अपि आधुनिकसंस्कृतलघुकथासाहित्यं अल्पमेव परिशीलितम्; विशेषतः स्वातन्त्र्योत्तरकाले प्रकाशितं गद्यरूपकं विरलम् एव साहित्यशास्त्रविद्भिः विविचितम्। १९५४–२०१५ इत्येतयोः मध्ये विरचितानां, विविधानां भारतीयराज्यानां लेखकानां लेखक्याश्च दशकथानां आधारेण, व्यक्तिनां स्वाभिलाषाः यदा पारम्परिकपारिवारिकाधिकारैः, नियोजितविवाहेन, विधीनां पालनेन, सामाजिकनिग्रहेन च सह सङ्घट्टन्ते तदा उत्पन्नानां संघर्षानां गतिः पुनर्निर्मीयते।
पद्धतिशः अस्य अध्ययनस्य केन्द्रभूतं चरितानां दृष्टिकोणग्रहणम्। सूक्ष्मविश्लेषणस्य समर्थनं मानवशास्त्रस्य कानूनी अध्ययनस्य च विविधनिष्कर्षैः भवति । होब्स्बाम् उक्तानां "कृतकपरम्पराणां" विचारः, कथानां "यथार्थवादस्य" च परीक्षणं बाह्यदत्तांशैः सन्दृश्यते।
अस्याः समीक्षायाः निष्कर्षाः दर्शयन्ति यत्, एतासु कथासु प्रतिपादनं विद्रोहस्य प्रायः नित्यजीवनाधारितं व्यक्तिगतम् उपायम्— न तु समग्रव्यवस्थाया एव विरोधः, किन्तु पारम्परिकसंरचनासु निवसन्ति ये जनाः तेषां प्रति प्रतिरोधरूपः। प्रतिक्रियाः सम्झौतां भावनात्मकनिवृत्तिः च पलायनं, व्यक्तिकरणं, नैमित्तिकविद्रोहं च भवन्ति । विद्रोहाः जटिलरूपेण निरूपिताः, कथासु च सफलाः भवन्ति। अन्ततः, आधुनिकसंस्कृतलघुकथासाहित्यं सामाजिक-नियमविरोधानां, व्यक्तिशक्तेः, सांस्कृतिकपरिवर्तनप्रक्रियाणां च अध्ययनाय अद्यावधि न्यूनमूल्यीकृतं, किन्तु अत्यन्तं महत्वपूर्णं corpus इति प्रदर्श्यते
Spectroscopy and the Path to Laser Cooling of Zinc
Get PDFTo enable laser cooling of zinc, a deep UV laser system for the main cooling transition at 214 nm has been developed. The system relies on frequency-quadrupling a titanium-sapphire laser in two consecutive frequency-doubling resonators, delivering up to 10 mW power from 4.3 W at the fundamental frequency. For interrogating the clock transition at 310 nm, a laser system has been constructed by frequency-quintupling of 1548 nm light, taking advantage of the possibility to distribute the clock signal through the existing telecom fiber networks. The system relies on one frequency-doubling and two sum frequency generation processes, eventually yielding 0.5 mW UV light.
A spectroscopic characterization of the 214 nm transition has been performed in collaboration with the Cold Molecule Group at the Fritz-Haber-Institut in Berlin. A beam of zinc atoms, cooled by collisions with He at 3 K, is excited with linearly polarized laser light whose frequency is stabilized to a stable ULE reference cavity. By measuring the fluorescence, isotope shift measurements on all stable isotopes have been performed improving literature values by more than one order of magnitude.
Furthermore, the absolute frequencies of 64Zn and the isotopic center-of-mass have been determined using a wavemeter. The hyperfine structure coefficients A and B of 67Zn, the only isotope with non-zero nuclear spin, have been determined considering the lineshape modification due to quantum interference. A King plot analysis exhibits the expected linearity proving consistency with literature values on the 308 nm line.
For establishing a high-resolution spectroscopy setup in Bonn, isotope shifts on the 423 nm transition of 40,42,44,48Ca have been measured with saturated absorption spectroscopy, improving literature values by a factor of 3. A lock-in technique is employed by sinusoidally modulating the intensity of the pump beam. Possible sources of systematic errors, e.g., buffer gas collisions and radiation pressure-induced distortions of the velocity distribution, are analyzed and either addressed in the experimental design or corrected for during data analysis. For narrow lines, self-collisions appear additionally so that future spectroscopy on intercombination lines should be performed on atomic beams. An optical setup including a ULE cavity to stabilize the laser frequency for the zinc intercombination line at 308 nm has been developed.
For future demonstration of the first laser cooling on zinc, an experimental setup for a magneto-optical trap has been constructed. The design includes the vacuum system, a thermal atom source and the coil system providing the magnetic field gradient. For clock experiments, the “magic” wavelength, at which the AC Stark shift cancels for the clock transition, is calculated to be 410 nm, at which confinement in the sideband-resolved Lamb-Dicke regime with suitable trap lifetimes appears possible
Functionalized Biaryls as Building Blocks for Non-Aggregating Molecular Spoked Wheels
Get PDFMolecular spoked wheels (MSWs) showed to be synthetically accessible in various sizes and functionalization in the past. Due to their construction of not only phenylene- but also acetylene- and bisacetylene-units, some of the molecules turned out to decompose when stored under ambient conditions for too long. To overcome such decomposition, the employed structural motifs were limited to all-phenylene subunits, that were more inert towards ambient conditions, but revealed limits considering their lateral expansion. Within the final synthetic step, the formation of intermolecular bonds was observed instead of the desired intramolecular cyclization reaction. Detailed investigation came to the conclusion, that the open-framed precursors’ tendencies to aggregate caused such intermolecular oligomerization.
Hence, this work deals with synthetic strategies to overcome the aggregation of all-phenylene MSW precursors. To do so, the established synthetic strategy was advanced. It was found to be helpful to introduce alkyl groups into the precursors’ spokes to 1) maintain high solubility during its preparation and 2) to separate the open-framed precursors that is it insufficient for them to aggregate. Two promising building blocks are fluorene and biphenol.
Fluorene comes with the advantage, that it can be halogenated regioselectively in 2- and 7-position, allowing the construction of large, nearly linear aromatic precursor molecules via transition metal catalysis in few steps. Besides that, the mentioned alkyl groups can be introduced into the motif straightforward because of its acidic 9,9’-position. Biphenol can be alkylated with similar ease, since its two hydroxy groups can be utilized as strong nucleophiles as well under mild basic conditions. Due to its electronic properties, a late halogenation of (alkylated) biphenol is not possible, requiring an elaborate synthesis of the unit from two moieties.
The synthetic investigations of the final cyclization were supported by quantum chemical simulations predicting their outcome. Due to the slightly bent geometry of fluorene, the resulting MSWs become bowl-shaped, making it unclear, if a cyclization of the rim fragments can occur successfully in the final step. Thus, each cyclization step of the six-fold closure was investigated individually regarding the distance between both fragments as well as the strain introduced into the molecule after a successful bond formation. In the end, the predictions turned out to be in full accordance with the synthetic evidence.
The accessed MSWs were structurally proven via NMR spectroscopy and mass spectrometry and scanning tunnelling microscopy (STM), providing valuable insights into their geometry, the orientation of the newly introduced spoke unit and their packing on highly oriented pyrolytic graphite (HOPG)