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Ageing well in the urban environment: meeting the health and social needs of older Adults - study protocol for a prospective, longitudinal mixed-methods study
No full textBackground: Urbanisation and ageing populations are global challenges for ageing well. This mixed-methods study examines the health and social needs of older adults in urban areas in Berlin, Germany and in Singapore, focusing on three key dimensions of healthy ageing and wellbeing: health, mobility, loneliness, and equity as a cross-cutting theme. Methods: The design follows a mixed-methods approach combining a quantitative longitudinal cohort study with qualitative interviews. For the quantitative cohort study, a standardised survey is carried out via home visits with a random sample of n = 1,050 adults aged 65 + years each in selected neighbourhoods in Berlin (three neighbourhoods) and Singapore (five neighbourhoods). The questionnaire comprises questions on health and health care utilization, neighbourhood, loneliness and social contacts, mobility and sociodemographic characteristics. Additionally, three functional tests (cognitive functioning, hand grip strength, and walking speed) are carried out with participants. Participants are followed-up after 12 months with a second survey interview. The survey data is linked with openly available geospatial data to allow for more in-depth study of the built-up and social environment and physical barriers in the selected neighbourhoods. For the qualitative component, walking interviews are conducted with n =50 people each in Berlin and Singapore focusing on older adults’ subjective perspective on health, mobility, green spaces and loneliness in their urban neighbourhood. The results of the different study components will be triangulated. Discussion: The Ageing Well Study offers a valuable opportunity to assess the health and social needs of older adults in two distinct urban contexts. The mixed-methods design and utilization of multiple data sources enables an examination of the various dimensions of ageing well from disparate angles and perspectives. The extensive quantitative data set permits the examination of associations and interlinkages between the various dimensions of ageing well and the living environment, as well as the identification of changes over a 12-month period. By opting for home visits, participants with limited mobility are more likely to participate. Minor adaptations of the instruments and methods were implemented to best suit local context, administrative regulations, and feasibility at the study site. Trial registration: The study has been registered prospectively at the German Register for Clinical Studies (DRKS) (DRKS00033043, registration date: 16th Nov 2023) which is part of the WHO International Clinical Trials Registry Platform (WHO ICTRP).Open Access funding enabled and organized by Projekt DEAL.Charité - Universitätsmedizin Berlin (3093)Peer Reviewe
Free-living nematodes as potential vectors and reservoirs for human pathogens
No full textFreilebende, sich von Bakterien ernährende Nematoden fressen, beherbergen und verbreiten menschliche Pathogene. In dieser Arbeit wurden die Wechselwirkungen zwischen Nematoden und Pathogenen sowohl in aquatischen als auch in terrestrischen Umgebungen untersucht, wobei der Schwerpunkt auf Legionella pneumophila (Süßwasser) und Salmonella enterica (Boden) lag. Das Potenzial von Nematoden, menschliche Pathogene zu beherbergen und/oder zu verbreiten, wird hauptsächlich durch ihre Anziehung zu den bakteriellen Pathogenen bestimmt. Daher konzentrierte sich diese Arbeit auf das Fressverhalten von Nematoden. Pharyngeale Pumptests zeigten, dass L. pneumophila die Fressaktivität der Nematodenarten Plectus similis und Plectus sp. im Vergleich zum Standardlaborfutter Escherichia coli OP50 beeinträchtigte. Darüber hinaus wurden natürliche Biofilme mit mCherry-markierten L. pneumophila allein oder in Kombination mit GFP-markierten E. coli inokuliert und das Beweiden der Bakterien durch die Nematoden wurde mithilfe von Laser-Scanning-Mikroskopie als Fluoreszenzmuster im Nematodendarm untersucht. Bemerkenswerterweise ernährten sich die getesteten Nematodenarten bevorzugt von L. pneumophila, wenn sie die Wahl zwischen E. coli und dem Pathogen hatten. Darüber hinaus wurde die Räuber-Beute-Beziehung zwischen Nematoden und S. enterica in einer Bodenumgebung untersucht. Binäre Auswahltests zeigten, dass sich der weit verbreitete Bodennematode Acrobeloides buetschlii sowie die beiden Modellorganismen Caenorhabditis elegans und Pristionchus pacificus sowohl von S. enterica als auch von gewöhnlichen Bodenbakterien ernährten, was auf eine Anpassung an mehrere bakterielle Ressourcen hindeutet. Insgesamt zeigte diese Arbeit, dass verschiedene freilebende Nematodenarten L. pneumophila und S. enterica als Ressource nutzen, was ihr Potenzial unterstreicht, als Umweltreservoir und/oder Vektor für menschliche Pathogene sowohl in Wassersystemen als auch in landwirtschaftlichen Böden zu dienen.It is becoming increasingly clear that free-living bacterial-feeding nematodes not only consume, but also harbor and disseminate human pathogens. In this thesis, the nematode-pathogen interactions were investigated in both, aquatic and terrestrial environments, with the emphasis on Legionella pneumophila (freshwater) and Salmonella enterica (soil). The potential of harboring and/or dissemination of human pathogens by nematodes is mostly shaped by their attraction to the bacterial pathogen. Therefore, this thesis focused on the feeding behavior of nematodes. Pharyngeal pumping assays revealed that L. pneumophila impaired the feeding activity of the nematode species Plectus similis and Plectus sp. compared to the standard lab food Escherichia coli OP50. Further, natural biofilms were inoculated with mCherry-labeled L. pneumophila solely or in combination with GFP-labeled E. coli and nematode grazing was assessed as fluorescence pattern in the gut, using laser scanning microscopy. Remarkably, the tested nematode species preferentially fed on L. pneumophila when given a choice between E. coli and the human pathogen. Additional feeding experiments with L. pneumophila and common bacterial taxa as resources revealed that food preference was not necessarily associated with an upregulation of pumping activity. Besides, the predator-prey relationship between nematodes and S. enterica was investigated in a soil environment. Binary choice assays revealed that the widespread soil nematode Acrobeloides buetschlii as well as the two model organisms Caenorhabditis elegans and Pristionchus pacificus fed on both, S. enterica and common soil bacteria, indicating an adaption to multiple bacterial diets. Overall, this thesis showed that different free-living nematode species use L. pneumophila and S. enterica as a resource, highlighting their potential to serve as environmental reservoir and/or vector for human pathogens in both, water systems and agricultural soil
Dreiundzwanzigste Änderung der Fächerübergreifenden Satzung zur Regelung von Zulassung, Studium und Prüfung der Humboldt- Universität zu Berlin (ZSP-HU) Herausgeber: Die Präsidentin der Humboldt-Universität zu Berlin Unter den
No full textQuantum Contextual Hypergraphs, Operators, Inequalities, and Applications in Higher Dimensions
No full textQuantum contextuality plays a significant role in supporting quantum computation and quantum information theory. The key tools for this are the Kochen–Specker and non-Kochen–Specker contextual sets. Traditionally, their representation has been predominantly operator-based, mainly focusing on specific constructs in dimensions ranging from three to eight. However, nearly all of these constructs can be represented as low-dimensional hypergraphs. This study demonstrates how to generate contextual hypergraphs in any dimension using various methods, particularly those that do not scale in complexity with increasing dimensions. Furthermore, we introduce innovative examples of hypergraphs extending to dimension 32. Our methodology reveals the intricate structural properties of hypergraphs, enabling precise quantifications of contextuality. Additionally, we investigate several promising applications of hypergraphs in quantum communication and quantum computation, paving the way for future breakthroughs in the field.Supported by the Ministry of Science and Education of Croatia through the Center of Excellence for Advanced Materials and Sensing Devices (CEMS) funding and by MSE grants No. KK.01.1.1.01.0001 and 533-19-15-0022. Also supported by the Humboldt Foundation, Germany. Computational support was provided by the Zagreb University Computing Centre.Ministry of Science and Education of CroatiaHumboldt Foundation, GermanyZagreb University Computing CentrePeer Reviewe
From “Single Sites” to Stable Nanoparticles Derived from Spray-Flame Synthesized Solid Solutions of Cobalt in MgO for Ammonia Decomposition
No full textChemical energy storage, in particular, the storage of hydrogen in carbon-free molecules such as ammonia, is being considered as an essential element in the transformation of our future energy system. In the present work, cobalt catalysts were investigated as alternatives to Ru- and Ni-based materials for the decomposition of ammonia. Spray-flame synthesis (SFS) was used to prepare metastable, phase-pure solid solutions Mg1–xCoxO, 0.03 ≤ x ≤ 0.47, as catalyst precursors composed of oxide nanoparticles with a particle size of 7–8 nm. In situ and operando XRD, H2-TPR studies, electron microscopy, Raman spectroscopy, and FTIR spectroscopy of adsorbed CO were applied to characterize the nanostructure of the host oxides and catalysts generated by exsolution of Co under reductive conditions. Calcination at 600 °C causes partial segregation of a Co3O4 spinel phase at a higher Co content (x ≥ 0.24). Small Co clusters are formed by exsolution from the solid solution, while the reduction of the spinel component yields Co nanoparticles of 3.3–8.5 nm. Very high space-time yields of 19 mmolH2·gcat–1·min–1 at 500 °C can be achieved due to the high dispersion of metallic cobalt. The turnover frequency (TOF) for metallic nanoparticles in the range between 1 and 5 nm remains constant at about 0.2 s–1, suggesting a structure insensitivity of the reaction in this size range at industrially relevant reaction conditions (500 °C, 100% NH3, WHSV of 36,000 N mL·g–1·h–1, 1 atm) caused by structural dynamics. Only atomically dispersed cobalt shows a TOF of about 0.5 s–1. The Co/Mg1–xCoxO catalysts exhibit very good stability even at high Co contents under the harsh conditions of ammonia decomposition due to strong metal–support interaction, making continuous SFS, which is potentially scalable, an attractive method for preparing cost-effective and resource-saving catalysts for ammonia decomposition.Peer Reviewe
Zum Spannungsfeld zwischen Entformalisierung und schützender Form
No full textDie Chancen und Risiken die eine Verständigung im Strafverfahren birgt, sind in der Literatur und Rechtsprechung bereits ausführlich analysiert worden. Dabei wird zumeist der Schwerpunkte auf die Frage der Vereinbarkeit von Verständigungen mit der Strafprozessordnung und tradierten Verfahrensgrundsätzen gesetzt. Ein weniger beleuchtet Aspekt ist die Möglichkeit ein Urteil, welches auf Grundlage einer Verfahrensabsprache zustande gekommen ist, revisionsrechtlich anzugreifen. Die Umsetzung der vom Bundesverfassungsgericht im sog. Verständigungsurteil geforderten vollumfänglichen und effektiven Kontrolle durch die Revisionsgerichte. Was auf den ersten Blick einfach erscheint, offenbart bei genauerer Betrachtung viele Schwierigkeiten. Schon in den Motiven und Zwecken, auf denen die Institute „Verständigung“ und „Revision“ fußen, zeigen sich ihre grundlegenden Unterschiede: Verständigungen entspringen einem Bedürfnis nach Praktikabilität und der Schonung von Ressourcen; die revisionsrechtliche Verfahrensrüge hingegen ist streng formalisiert und soll die Wahrung strafprozessualer Grundsätze eines ebenso formalisierten Verfahrens gewährleisten. Dieses Spannungsfeld zwischen Entformalisierung und schützender Form und den Umgang hiermit durch die Rechtsprechung soll in dieser Arbeit aufgezeigt werden Kernteil der Arbeit ist eine umfangreiche Analyse der Rechtsprechung des Bundesgerichtshofs zu Revisionen, die Verstöße gegen das seit 2009 geltende Verständigungsgesetz betreffen. Die Dissertation zeigt auf, dass der Umgang des Bundesgerichtshofs mit Verstößen gegen das Verständigungsgesetz zu einem paradoxen Zustand innerhalb der revisiongerichtlichen Rechtsprechung geführt hat. In der Schlussbetrachtung werden diese gegenläufigen Entwicklungstendenzen aufgezeigt und ein Erklärungsansatz geboten.The opportunities and risks associated with plea agreements in criminal proceedings have already been extensively analyzed. Most discussions focus on the compatibility of such agreements with the German Code of Criminal Procedure and established procedural principles. One aspect however, that has only received little attention is the possibility of challenging a verdict that is based on a plea agreement through the Federal Court of Justice. This dissertation addresses the implementation mandated by the Federal Constitutional Court in 2013. What may seam simple, reveals numerous difficulties upon closer examination. The underlying motives and purposes of the legal institutions of plea agreements and appeals show fundamental differences: Plea agreements stem from a need for practicality and conversation of resource, whereas the rights of appeal are strictly formalized and aim to protect formalized procedural principles. How the Federal Court navigates this tension between informal negotiation and the protective structure of formal procedure is the aim of this thesis. The dissertation contains an in-depth analysis of all the decisions the Federal Court made based on violations of the Plea Agreement. The thesis demonstrates that the Federal Court’s handling of such violations has led to a paradoxical state within appellate jurisprudence and offers an explanation for these contradictory developments
Social Justice after the 20th Century. Edited by Martin Conway and Camilo Erlichman
No full textThe history of present-day Europe is often written as a story of decline. For many, it is the collapse of the certitudes of the post-war era that most obviously characterizes the European societies of the present. The erosion of mass political parties, the electoral triumph of new populist movements, the return of armed conflict to the continent and above all the extent to which politics has simply ceased to be predictable are trends which have encouraged historians to contrast the stability of the post-war era with the fragility and volatility of the present. Present-day Europe, to draw on the influential phraseology used by Carl Schorske about the 1890s, has entered a distinctively new key, and its internal logics no longer seem to follow the norms of the 20th century. The perceived resurgence in social inequality is central to this understanding of the recent history of Europe. Since the economic shocks of the 1970s, the associated increase in unemployment in western European societies and the capitalist transformation of the states of east-central Europe after 1989/90, the history of recent decades appears to have been dominated by a retreat of the ambition to achieve socially just societies, leading to a continuous exacerbation of material inequality. Consequently, contemporary historians have in recent years spent much ink exploring the ways in which market-fundamentalist ideas have reconfigured European societies since the late 1970s. The 1990s play an important role in these narratives, as the moment when the welfare states that had been built incrementally in Europe over previous decades came under serious attack and were partly dismantled by governments seeking to curb spending. In this interpretation, the story of social justice since the collapse of state socialism in 1989/90 can be told in a rather straightforward manner as one of decay in the face of a neoliberal onslaught. There is much to commend an approach that emphasizes how the last decades of the 20th century disrupted the centrality of social justice in the history of European societies. The purpose of our recent collective book Social Justice in 20th-Century Europe was to show how different versions of social justice had developed across the century, demonstrating the extent to which very different political groups and regimes had competed for ownership of the meaning of social justice. As we argued in that book, there was much plurality and change; but at the same time, these divergent conceptions of social justice were rooted in the more durable confessional and ideological worlds of Europe. Above all, during the 20th century, social justice became a central source of political legitimacy that those in power ignored at their peril.Peer Reviewe
Aphid wing polyphenism and conspecific egg cannibalism affect the developmental and reproductive performance of Chrysoperla carnea
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Aphid polyphenism and egg cannibalism may have nutritional consequences for the development, survival, and reproduction of predatory insects. Although predators have the same probability of attacking winged and wingless morphs in natural conditions, an increment in the proportion of winged morphs dispersed under predation risk may have a negative effect on predator feeding by reducing the size of the wingless form available on the plant. However, the wingless aphids may be richer in nutritional value than the dispersed winged aphids. Therefore, the nutritional consequences of aphid morphs and egg cannibalism for development, survival, 10-clutch fecundity and fertility, and the time needed for 10 clutches of eggs Chrysoperla carnea were addressed via a series of experiments. Wingless aphids accelerated the total development and increased the survival of C. carnea compared to the winged aphids. Furthermore, feeding with the wingless form increased the 10-clutch fecundities and fertilities, and reduced the days needed for 10 clutches of eggs. Neonate larvae of C. carnea that devoured two conspecific eggs took a shorter time with an acceleration in the overall development of C. carnea. Immature mortality was higher in controls than in the cannibalism treatment. Reproductive benefits were obvious in females permitted to consume two conspecific eggs during their first instar compared to those that did not. However, the time needed for 10 ovipositions did not differ between both groups. These findings are ecologically significant because C. carnea females are able to adapt to the stresses imposed by nature without needing winged aphid prey to distribute their eggs widely, as their larvae can grow on their own eggs and gain developmental and reproductive benefits from such behavior when prey availability or quality is low.Peer Reviewe
Statistical and Algorithmic Network Analysis: a Structural Perspective
No full textKomplexe Netzwerke kodieren Strukturinformationen der zugrunde liegenden Systeme, die modelliert werden. Die Dekodierung der Strukturinformationen aus einem Netzwerk kann uns daher helfen, die Funktionsweise der zugrunde liegenden Systeme zu verstehen und sogar vorherzusagen. Vor diesem Hintergrund untersuchen wir drei Probleme: Multistabilität in vernetzten dynamischen Systemen, globale Muster extremer Niederschläge und Graphenverdünnung. Indem wir die drei Probleme angehen, wollen wir den Werkzeugkasten der Netzwerkwissenschaft erweitern und die Integration von Netzwerkwerkzeugen in andere Forschungsfelder fördern. Erstens ist das Verständnis der Entstehung von Multistabilität oder sogar extremer Multistabilität (EM) in vernetzten dynamischen Systemen immer noch ein herausforderndes Problem. Dazu zeigen wir mithilfe eines multistabilen Modells gekoppelter Pendeluhren (kurz: gekoppelte Uhren), dass eine symmetrische Kopplung die Komplexität der Multistabilität erhöhen und die durch Kopplung verursachte EM aufdecken kann. Als nächstes bilden in der Klimawissenschaft räumliche Muster die Grundlage für die Erforschung der geophysikalischen Mechanismen, die für die Muster verantwortlich sind. Wir betrachten die Identifizierung räumlicher Regionen mit ähnlichem Verhalten extremer Niederschläge als Clusterproblem und schlagen einen netzwerkbasierten Cluster-Workflow vor. Mithilfe dieses Workflows identifizieren wir zwei robuste Muster extremer Niederschläge auf globaler Ebene. Schließlich ist Graphensparsifizierung in der Informatik eine verlustbehaftete Komprimierungstechnik, die die Erhaltung repräsentativer Eigenschaften für Graphendaten erfordert. Zu diesem Zweck schlagen wir ein generisches Edge-Sampling-Framework vor, indem wir die Sparsifizierung als Optimierungsproblem formulieren. Experimentelle Auswertungen bestätigen die Wirksamkeit unserer Methode bei der Erhaltung repräsentativer Netzwerkeigenschaften (im Durchschnitt) besser als der Stand der Technik.Complex networks encode structure information of the underlying systems being modeled. Decoding the structure information from a network can therefore help us to understand and even to predict the functioning of the underlying systems. With this in mind, we explore three problems: multistability in networked dynamical systems, global patterns of extreme rainfall, and graph sparsification. By addressing the three problems, we aim to extend the toolbox of network science and promote the integration of network tools with other research fields. First, understanding the emergence of multistability or even extreme multistability (EM) in networked dynamical systems is still a challenging problem. For this, using a multistable model of coupled pendulum clocks (coupled clocks for short), we reveal that a symmetric coupling can increase the complexity of multistability, and uncover the coupling-induced EM. Next, in climate science, spatial patterns provide the basis for the exploration of the geophysical mechanisms responsible for the patterns. We consider the identification of spatial regions of similar extreme rainfall behavior as a clustering problem, and propose a network-based clustering workflow. Using this workflow, we identify two robust patterns of extreme rainfall on a global scale. Finally, in computer science, graph sparsification is a lossy compression technique requiring preserving representative properties for graph data. For this, we propose a generic edge sampling framework by formulating sparsification as an optimization problem. Experimental evaluations verify the effectiveness of our method in preserving representative network properties (on average) better than the state of the art
High-Precision Surface Tension Measurements of Sodium, Potassium, and Their Alloys via Du Noüy Ring Tensiometry
No full textThe development of post-lithium-ion batteries has sparked significant interest in alkali-metal anodes, particularly sodium (Na), potassium (K), and sodium–potassium (Na–K) alloys. Na–K alloys are promising for partially liquid anodes due to their unique low melting points. A critical factor influencing Na–K-based anode performance is wetting behavior, which governs electrical conductivity, mechanical contact, and long-term stability. At the heart of wetting lies surface tension, a fundamental property of solid–liquid–gas interactions. However, the surface tension of alkali metals and their alloys, particularly Na–K systems, remains poorly understood due to experimental and theoretical challenges. This study bridged these gaps by employing Du Noüy ring tensiometry for the first time in alkali-metal systems to measure the surface tension of Na, K, and Na–K alloys across temperatures from ambient to 180 °C. A key innovation in this work is the development of the push-in Du Noüy method, which provided significantly higher precision and reliability compared to the traditional pull-out technique, without requiring a correction factor. The measured surface tension decreased with increasing temperature for the studied Na–K alloys. For instance, for a eutectic Na–K mixture, the surface tension decreases from 121.7 mN m –1 to 112.2 mN m –1 when increasing the temperature from ambient to 180 °C. Additionally, this study presented the first use of Gibbs free energy minimization to model the surface tension of the Na–K system. The robust method significantly enhanced the predictive accuracy compared to the previous simplified model, reducing deviations from 25% to 2%. Our findings reveal that surface tension increases with sodium mole fraction in the bulk phase, yet the surface monolayer remains potassium-rich, indicating non-ideal surface behavior. This study deepens the understanding of alkali-metal wetting behavior, providing valuable insights for designing optimized interfaces in next-generation semi-solid alkali-metal batteries.Fonds der Chemischen Industrie 10.13039/100018992Bundesministerium f?r Bildung und Forschung 10.13039/501100002347Humboldt-Universit?t zu Berlin 10.13039/501100006211DAAD RISE Germany program NAPeer Reviewe