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A Self-Driving Lab for Nano- and Advanced Materials Synthesis
No full textThe recent emergence of self-driving laboratories (SDL) and material acceleration platforms (MAPs) demonstrates the ability of these systems to change the way chemistry and material syntheses will be performed in the future. Especially in conjunction with nano- and advanced materials which are generally recognized for their great potential in solving current material science challenges, such systems can make disrupting contributions. Here, we describe in detail MINERVA, an SDL specifically built and designed for the synthesis, purification, and in line characterization of nano- and advanced materials. By fully automating these three process steps for seven different materials from five representative, completely different classes of nano- and advanced materials (metal, metal oxide, silica, metal organic framework, and core–shell particles) that follow different reaction mechanisms, we demonstrate the great versatility and flexibility of the platform. We further study the reproducibility and particle size distributions of these seven representative materials in depth and show the excellent performance of the platform when synthesizing these material classes. Lastly, we discuss the design considerations as well as the hardware and software components that went into building the platform and make all of the components publicly available.Peer Reviewe
An analysis of the microalgae Technological Innovation System in Germany
No full textMikroalgen werden als vielversprechende Ressource für eine nachhaltige Bioökonomie und Kreislaufwirtschaft betrachtet. Ihre Nutzung spielt dennoch eine untergeordnete Rolle. In der vorliegenden Studie wurde die Relevanz von Mikroalgen als Ressource in Deutschland betrachtet. Die Analyse basiert auf der Betrachtung des technologischen Innovationssystems (TIS), das durch eine Literaturrecherche und Expert*inneninterviews mit Akteur*innen aus der Mikroalgenproduktion, der Wissenschaft, dem Großhandel, dem Anlagenbau und Netzwerken ermittelt wurde. Die Ergebnisse zeigen, dass Mikroalgenanwendungen in einer Vorentwicklungsphase (Bioenergie, Biomaterialien, Ökosystem-dienstleistungen), Entwicklungsphase (hochwertige Moleküle, landwirtschaftliche Produkte) und Wachstumsphase (Nahrungsergänzungsmittel) sind. Die TIS-Funktionen ‚Schaffung von Legitimität‘, ‚unternehmerische Aktivitäten‘ und ‚Marktformierung‘ unterstützen die TIS-Entwicklung. Die Funktionen ‚Wissensverbreitung‘ und ‚Ressourcenmobilisierung‘ limitieren den Fortschritt. ‚Wissensentwicklung‘ und ‚Einfluss auf die Suchrichtung‘ haben einen uneindeutigen Effekt. Basierend darauf wurden drei Blockierungsmechanismen ermittelt. Erstens gibt es keine ausreichende Kooperation zwischen Forschung und Industrie zur Entwicklung von marktfähigen Produkten; zweitens keine ausreichenden Finanzierungsmöglichkeiten für Mikroalgenunternehmen; drittens werden importierte Mikroalgen nicht ausreichend auf Schwermetallbelastungen überprüft. Um diesen Blockierungsmechanismen entgegenzuwirken, wurden drei Politikempfehlungen entwickelt. Erstens die Etablierung von lokalen Innovationsclustern mit gemeinschaftlich genutzten Reallaboren; zweitens die Schaffung eines Finanzierungsprogramms für Mikroalgenunternehmen; drittens die Entwicklung eines Maßnahmenpakets für bessere Importkontrollen und die Unterstützung der lokalen Produktion. Diese Politikempfehlungen haben das Potential zentrale Blockierungsmechanismen im TIS zu vermeiden.Microalgae are considered a promising resource for a sustainable bioeconomy and circular economy that still plays a minor role as a natural resource. This study examined the relevance of microalgae as a resource in Germany. The analysis was conducted through an assessment of the German microalgae Technological Innovation System (TIS), based on a literature review and expert interviews with microalgae producers, researchers, retailers, network actors, and equipment manufacturers. Results show that the food supplement sector is in a take-off phase, while other application areas are still in the pre-development phase (bioenergy, biomaterials, ecosystem services) or development phase (extraction of high-valued molecules, agricultural products). The TIS functions ‘creation of legitimacy’, ‘entrepreneurial activities’, and ‘market formation’ facilitate the TIS development. The system functions ‘knowledge diffusion’ and ‘resource mobilization’ are restricting its progress. ‘Knowledge development’ and ‘guidance of the search’ are characterized by enabling and restrictive impacts. Based on this, three system failures are identified. First, there is a lack of cooperation between research institutions and industry to transfer knowledge into marketable products; second, there is insufficient funding for microalgae companies; and third, there is a lack of control over the import of microalgae with heavy metal contamination. To mitigate these system failures, three policy recommendations were formulated. First, the creation of locally based microalgae innovation clusters in conjunction with a jointly used living lab for sample productions; second, the creation of a separate funding program for microalgae-related companies; and third, the creation of a package of measures with stricter controls at the borders and support of local production. These policy recommendations have the potential to mitigate central system failures in the German microalgae TIS
Diversification strategies to improve cocoa farmers’ household income: the case of Côte d’Ivoire
No full textDiversification is a strategy adopted by farming households to meet several challenges. However, there is a lack of empirical evidence to support these positions. We contribute to filling this research gap by providing quantitative evidence of the impact of diversification on the additional income of cocoa-producing households. This study aims to analyze income from the diversification strategies of cocoa producers by building the typology of the most common systems and assessing their impacts on household income. A survey of 303 households across five Côte d’Ivoire regions reveals that cocoa producers have four distinct types of production systems, namely: (1) simple cocoa production systems; (2) cocoa production systems with crops in association; (3) cocoa production systems combined with income generating diversification on the additional plot; and (4) cocoa production systems, and food cropland. Of the four systems, type 3 is the most widely adopted by cocoa producers, generating higher income per household than the other types due to the large part of perennial income that requires a larger area. Furthermore, type 2 presents the best cocoa yield. We also assessed differences per population group. Thus, the results show that women adopt type 2 and type 4 systems with less surface area and are more devoted to the production of subsistence crops. Non-Ivorian producers have systems with higher cocoa yields and income from diversification than Ivorian producers. However, only 7% of producers have access to financing enabling them to invest in diversification crops. The findings demonstrate that crop diversification strategies can successfully improve households’ living income and ensure the sustainability of cocoa production.Peer Reviewe
Private intergroup relationships between natives and migrants
No full textIn dieser Dissertationsarbeit werden die Determinanten interethnischer Beziehungen zwischen Nicht-Migranten und Migranten untersucht. Aus theoretisch Sicht baut die Arbeit auf der Idee auf, dass drei Mechanismen die Muster der Beziehungsbildung beeinflussen können: Kontaktmöglichkeiten, Präferenzen und das Verhalten Dritter. Der einleitende Teil der Arbeit gibt einen Überblick über die Literatur im Feld. Darauf aufbauend entwickle ich eine Forschungsagenda. Drei Beiträge tragen zu dieser Agenda bei: Gestützt auf Längsschnittanalysen zeigt der erste Beitrag, dass ein mäßig hoher Migrantenanteil in der Nachbarschaft mit mehr interethnischen Beziehungen zusammenhängt. Zusätzlich unterhalten Personen, die sich durch Einwanderung und Migranten bedroht fühlen, mit geringerer Wahrscheinlichkeit interethnische Beziehungen, während Mitgefühl mit Migranten in die entgegengesetzte Richtung wirkt. Im zweiten Beitrag wird für migrantische- und nicht-migrantische Paare untersucht, wie sich eigene Einstellungen, Ressourcen und die Zusammensetzung des sozialen Netzwerks auf die interethnischen Freundschaften und Bekanntschaften des Ehepartners auswirken. Ich stelle fest, dass Partnermerkmale eine wichtige Rolle für die interethnischen Beziehungen einer Person spielen. Im dritten Beitrag untersuche ich, ob und wie sich die interethnischen Beziehungen einer Person von ihren intraethnischen Beziehungen unterscheiden. Zusätzlich erkläre ich Unterschiede und Gemeinsamkeiten zwischen diesen. Die Ergebnisse deuten darauf hin, dass die Unterschiede zwischen interethnischen und intraethnischen Beziehungen einer Person weniger ausgeprägt sind als in der Gesellschaft im Allgemeinen. Allerdings spiegeln enge Beziehungsnetzwerke auch bis zu einem gewissen Grad die Unterschiede zwischen Migranten und Nicht-Migranten wider. Die Dissertationsarbeit schließt mit Hinweisen auf weiteres Forschungspotential innerhalb des Feldes.This thesis studies the determinants of interethnic relationships between non-migrants and migrants. Theoretically, the thesis builds on the idea that three mechanisms might influence the patterns of relationship formation: opportunities, preferences, and third parties. The introductory part of the thesis reviews the literature in the field. Building on this review, I develop a research agenda. Three papers advance this agenda: Building on longitudinal analyses, the first paper shows that moderately high migrant shares in the neighbourhood are connected to more interethnic relationships. Additionally, persons feeling threatened by immigration and migrants are largely found to be less likely to have interethnic relationships, while sympathy with migrants works in the opposite direction. Considering both non-migrant and migrant couples, the second paper studies the effect of cohabiting life partners’ attitudes, resources, and social network compositions on their spouse’s interethnic friendships and acquaintances. I find that partner characteristics play an important role for a person’s interethnic relationships. In the third paper, I study if and how a person’s interethnic ties differ from their intraethnic ties. Additionally, I explain differences and similarities between them. Results suggest that differences between a person’s interethnic and intraethnic ties are less pronounced within close relationship networks than they are in society in general. However, close relationship networks mirror to some extent migrant - non-migrant differences. The thesis concludes by identifying further research potential in the field
African Initiated Churches and Ecological Sustainability: An Empirical Exploration
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.While African Initiated Churches are increasingly recognized as actors of social development, little research has thus far elucidated their role regarding ecological sustainability. Responding to this gap, we explore African Initiated Churches’ views on ecological sustainability and their reaction to environmental destruction and climate change. We analyse to what extent environmental concerns are considered relevant, explore emerging environmental concepts and theologies, and highlight environmental actions taken. The analysis is based on a diverse set of qualitative and quantitative data focusing on leaders of African Initiated Churches from across Sub-Saharan Africa: interviews and focus groups, public lectures, and online survey data. The findings show an ecological turn in African Initiated Christianity. Unlike in mainline Christianity, where ecological engagement is often embedded in elaborated eco-theologies, African Initiated Churches’ engagement with ecological sustainability seems to be primarily driven by the increasing adverse effects of environmental degradation and climate change in their communities
Microbial Food Safety Aspects Along the Supply Chain of African Indigenous Vegetables. A Case Study of Leaf Amaranth (Amaranthus spp.) in Kenya
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Microbial food safety aspects along the supply chain of fresh leaf amaranth (Amaranthus spp.) were evaluated from farms to urban supermarkets in Kenya. A total of 150 leaf samples were collected from amaranth farms, transport, wholesale, peri-urban retail markets, and supermarkets. Microbiological indicators of sanitary conditions were analyzed in terms of the prevalence and load of aerobic mesophilic bacteria, Enterobacteriaceae, total coliforms, yeasts & molds, Escherichia coli, Salmonella, and Staphylococcus aureus. Foodborne pathogens, E. coli, Salmonella, and S. aureus, were characterized through molecular screening for selected virulence genes. The prevalence of microbial contamination was highest in peri-urban retail markets, followed by wholesale markets, supermarkets, and transportation, and least on farms. Throughout the supply chain, coliforms were the most prevalent, detected in 98.7% of the samples, followed by Enterobacteriaceae (97.3%), aerobic mesophiles (96.7%), and yeasts and molds (92%). However, S. aureus was the most prevalent pathogen (87.3%), followed by Salmonella (79.3%) and E. coli the least (67.3%). Microbial load increased from the farm to peri-urban retail markets and was significantly higher in the peri-urban retail markets, i.e., 5.08–6.22 Log CFU/g (aerobic mesophiles), 5.28–6.32 Log CFU/g (Enterobacteriaceae), 5.56–6.47 Log CFU/g (coliforms), 2.02–3.59 Log CFU/g (E. coli), 3.87–4.64 Log CFU/g (S. aureus), and 3.36–4.23 Log CFU/g (Salmonella), respectively. Shiga toxin-producing E. coli virulence genes (stx1 and stx2), enterotoxin (stn), and plasmid (pCT) Salmonella virulence genes, and S. aureus virulence genes (sea) were detected in isolates from vegetables at different nodes of the supply chain. Microbial contamination levels were above the international and national thresholds, and foodborne microorganisms had pathogenic attributes. Initiatives to improve sanitation measures at each stage of the supply chain are recommended to guarantee food safety
High-quality deepfakes have a heart!
No full textIntroduction: Deepfakes have become ubiquitous in our modern society, with both their quantity and quality increasing. The current evolution of image generation techniques makes the detection of manipulated content through visual inspection increasingly difficult. This challenge has motivated researchers to analyze heart-beat-related signal to distinguish deep fakes from genuine videos.
Methods: In this study, we analyze deepfake videos of faces generated with novel methods regarding their heart-beat-related signals using remote photoplethysmography (rPPG). The rPPG signal describes the blood flow based, or rather local blood volume changes, and thus reflects the pulse signal. For our analysis, we present a pipeline that extracts rPPG signals and investigate the origin of the extracted signals in deepfake videos using correlation analyses. To validate our rPPG extraction pipeline and analyze rPPG signals of deepfakes, we captured a dataset of facial videos synchronized with an electrocardiogram (ECG) as a ground-truth pulse signal. Additionally, we generated high-quality deepfakes and incorporated publicly available datasets into our evaluation.
Results: We prove that our heart rate extraction pipeline produces valid estimates for genuine videos by comparing the estimated results with ECG reference data. Our high-quality deepfakes exhibit valid heart rates and their rPPG signals show a significant correlation with the corresponding driver video that was used to generate them. Furthermore, we show that this also holds for deepfakes from a publicly available dataset. Discussion: Previous research assumed that the subtle heart-beat-related signals get lost during the deepfake generation process, making them useful for deepfake detection. However, this paper shows that this assumption is no longer valid for current deepfake methods. Nevertheless, preliminary experiments indicate that analyzing spatial distribution of bloodflow regarding its plausibility can still help to detect high quality deepfakes
Verbal Fluency Selectively Predicts Survival in Old and Very Old Age
No full textIntelligence is known to predict survival, but it remains unclear whether cognitive abilities differ in their relationship to survival in old age. We analyzed longitudinal data of 516 healthy adults (age: M = 84.92 years, SD = 8.66 years at Wave 1) from the Berlin Aging Study (Germany) on nine tasks of perceptual speed, episodic memory, verbal fluency, and verbal knowledge, and a general composite intelligence score. There were eight waves, with up to 18 years of follow-up; all participants were deceased by the time of analysis. We used a joint multivariate longitudinal survival model to estimate the unique contribution of each cognitive ability in terms of true (i.e., error-free) current value and current rate of change when predicting survival. Additional survival covariates included age at first occasion, sex, sociobiographical status, and suspected dementia. Only the two verbal-fluency measures were uniquely predictive of mortality risk. Thus, verbal fluency showed more salient associations with mortality risk than did measures of perceptual speed, episodic memory, and verbal knowledge.max-planck-gesellschaft https://doi.org/10.13039/501100004189freie universität berlin https://doi.org/10.13039/501100007537bundesministerium für forschung und technologie https://doi.org/10.13039/501100004937the German Federal Ministry for Family, Senior Citizens, Women, and YouthBerlin-Brandenburg Academy of SciencesPeer Reviewe
Decolonising Evaluation Practice in International Development Cooperation Through an African Religion Lens
No full textThe article processing charge was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – 491192747 and the Open Access Publication Fund of Humboldt-Universität zu Berlin.This paper critically addresses the pervasive neglect of indigenous approaches to social transformation within the field of international development cooperation. It shows how commonly used evaluation frameworks—shaped by Western assumptions about evidence, measurement, and progress—tend to exclude non-Western knowledge systems. Focusing on African Initiated Churches (AICs) as exemplars of development actors with transformational approaches that incorporate the spiritual, this study explores the possible reforms required in mainstream evaluation practices to recognise and include development alternatives. An analysis of AIC evaluation practices reveals the potential for decolonised frameworks rooted in African and indigenous epistemologies, including relational, communal, and spiritual ways of generating evidence. This paper argues that fostering mutual learning and dialogue in the field of development evaluation is fundamental to driving more inclusive and sustainable social change.Peer Reviewe
The Post-Secular Cosmopolitanization of Religion
No full textThe contemporary restructuring of religion and secularism demands a departure from conventional post-secular analyses that remain confined within the epistemic and institutional frameworks of the nation-state. This paper develops the concept of post-secular cosmopolitanization to theorize the dissolution of the secular–religious binary as a regulatory mechanism of power, revealing how religion and secularism are co-constituted through global entanglements that transcend national boundaries. Unlike dominant conceptions of post-secularism, which assumes the continued dominance of secular and national institutions despite religious resurgence, post-secular cosmopolitanization captures the ways in which transnational religious movements, digital religious networks, and global governance structures are reshaping religious authority, secular regulation, and political sovereignty. It is shown that this transformation leads to three major consequences: (1) the erosion of the nation-state’s regulatory monopoly over religious life as alternative religious and transnational actors emerge as influential governance entities; (2) the deterritorialization and fragmentation of religious authority, undermining traditional clerical and institutional hierarchies; and (3) the blurring of religious and secular domains, where global economic, legal, and political structures increasingly integrate religious actors, norms, and ethical frameworks. These developments signal a paradigmatic shift beyond the secularization thesis and dominant conceptions of post-secularism, necessitating a reconsideration of how power, governance, and religious authority function in a world no longer structured by the nation-state’s exclusive claim to sovereignty. By analyzing these entanglements, this paper provides a theoretical framework to understand the reconfiguration of global secular and religious orders, challenging entrenched assumptions about the trajectory of modernity.Peer Reviewe