31325 research outputs found
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Vector Abundance and Genetic Diversity of Anopheles Mosquitoes Collected in a Laboratory–Office Complex in Vom, Nigeria: Implications for Vector Control
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Malaria remains a significant threat in high‐burden high‐impact (HBHI) countries despite substantial investments in disease control. This highlights the need for more comprehensive and inclusive strategies to meet national and international targets. Although agricultural and poorly maintained environments are known for mosquito breeding, workplaces are rarely considered in conventional malaria control measures. In this pilot investigation, we assessed the presence of Anopheles spp. in a laboratory–office complex in Vom, Nigeria, to assess workplace malaria risk and its implications for control strategies. We conducted molecular barcoding on 74 Anopheles specimens targeting the mitochondrial cytochrome oxidase I gene ( cox1 ). Our analyses identified Anopheles funestus ( n = 29; 54.6%), Anopheles gambiae sensu lato ( n = 17; 32.1%), and Anopheles rufipes ( n = 6; 11.3%). Haplotype network analyses revealed 12, 8, and 6 distinct haplotypes for A . funestus , A . gambiae , and A . rufipes , respectively. Genetic divergence estimates for cox1 sequences were ≤0.011% for A. funestus , ≤0.007% for A. gambiae , and ≤0.018% for A. rufipes . The detection of genetically diverse Anopheles vector species in an office setting underscores the potential risk of workplace malaria transmission. This pilot study provides initial evidence that workplace environments can harbor genetically diverse malaria vectors and should be considered in future surveillance and control strategies. We recommend subnational tailoring (SNT) of intervention strategies to incorporate workplace environments and public places into malaria control efforts.the German Research FoundationPeer Reviewe
From lab to forest: overcoming barriers to in vitro propagation of forest trees
No full textReforestation initiatives are often limited by insufficient seeds, a problem exacerbated by natural variability in tree flowering and seed production and climate change and other environmental challenges. Innovative and adaptive solutions such as in vitro propagation are thus needed. Tissue culture can provide high-quality propagation material for tree conservation and mass propagation, but faces technical, economic, regulatory, and social barriers. Obstacles related to the academia–industry interface and to stakeholder concerns are discussed and actions suggested to overcome these barriers to realize the full potential of tree micropropagation. These include refining techniques to improve efficiency and reduce costs; establishing collaborations among researchers, industry, and foresters; and reducing points of contention and misinformation regarding genetic diversity and public perception. International collaborative initiatives, exemplified by the EU COST Action CA21157 COPYTREE, are elementary for achieving these goals.Open access funding provided by Natural Resources Institute Finland.Natural Resources Institute FinlandPeer Reviewe
Different aspects of relevancy during emotional episodes evaluations
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.The present research investigates the effect of relevance on our subjective experience while generating alternative events in our mind. To accomplish this aim, we asked participants to read and visualize 280 situations outlined in concise scripts. During each trial, they evaluated the relevance of the situation and other aspects of their metacognitive and emotional experience using a Likert scale ranging from 1 to 9. We employ PLS-SEM (partial least squares structural equation modelling) to investigate a potential causal sequence among three tiers of latent components. Specifically, the situational level consists of relevancy and plausibility factors, the metacognitive level consists of an imaginability factor, and the subjective experience level consists of feeling and thought suppression factors. Our analysis indicates that the effect of the plausibility of alternative scenarios on subjective experience is mediated by both the relevance and imageability factors, regardless of whether events are negative or positive. Furthermore, we successfully replicated the negativity rejection bias shown in our prior work. This bias refers to the tendency of participants to perceive bad events as less likely to occur than good events, independent of the precise details of those events.Peer Reviewe
Hydrological connectivity and water quality dynamics of drought-sensitive, beaver-influenced, intermittent stream networks and adjacent water bodies in a lowland catchment
No full textPeriodisch wasserführende Bäche in Agrarlandschaften werden zunehmend durch Dürre, unregelmäßige Niederschläge und Grundwasserveränderungen beeinträchtigt, was die hydrologische Vernetzung und Wasserqualität verändert. Diese Arbeit untersucht, wie Dürre, Landnutzung und naturbasierte Lösungen (NbS) zusammenwirken, um Nährstoffkreisläufe und die Resilienz von Ökosystemen zu regulieren. Mehrjährige Beobachtungen zeigen drei hydrologische Phasen – Vernetzung, vollständige Vernetzung und Trennung –, die jeweils mit einer spezifischen Dynamik gelöster Stoffe einhergehen. Dürre verlängert die Trennung und verstärkt redoxgetriebene Prozesse wie Denitrifikation, Phosphorfreisetzung und die Produktion von gelöstem organischem Kohlenstoff, während sie gleichzeitig die Vernetzung einschränkt. Biberdämme und Feuchtgebiete wirken als NbS, indem sie die Nitratentfernung, die Grundwasserneubildung und die hydrologische Resilienz verbessern, jedoch oft verbunden mit der Freisetzung von Kohlenstoff und Phosphor, was die Nährstoffkompromisse verdeutlicht. Der Stoffwechsel der Bäche wird ebenfalls durch die hydrologische Variabilität beeinflusst, wobei Dürre und Fragmentierung die Heterotrophie erhöhen und die Sauerstoffdynamik verändern. Insgesamt erweist sich die hydrologische Vernetzung als zentraler Faktor für die Wasserqualität und die Funktion des Ökosystems. Dies unterstreicht die Notwendigkeit integrierter, auf das gesamte Einzugsgebiet bezogener naturbasierter Lösungen, um landwirtschaftliche Fließgewässer unter den Bedingungen des Klimawandels zu erhalten.Intermittent streams in agricultural landscapes are increasingly altered by drought, rainfall variability, and groundwater change, reshaping hydrological connectivity and water quality. This thesis examines how drought, land use, and nature-based solutions (NbS) interact to regulate nutrient cycling and ecosystem resilience. Multi-year observations reveal three hydrological phases—connecting, fully connected, and disconnecting—each associated with distinct solute dynamics. Drought extends disconnection, intensifying redox-driven processes such as denitrification, phosphorus release, and dissolved organic carbon production, while constraining connectivity. Beaver dams and wetlands act as NbS by enhancing nitrate removal, groundwater recharge, and hydrological resilience, though often coupled with carbon and phosphorus release, underscoring nutrient trade-offs. Stream metabolism is also shaped by hydrological variability, with drought and fragmentation increasing heterotrophy and altering oxygen dynamics. Overall, hydrological connectivity emerges as the central regulator of water quality and ecosystem function, highlighting the need for integrated, catchment-scale NbS to sustain agricultural streams under climate change
Evidence from the Global South
No full textZiel dieser Forschung ist es, die Bedeutung und das Potenzial von Open Science in Pakistan, einem Land der südlichen Hemisphäre, zu verstehen. Die Studie konzentriert sich insbesondere auf die Analyse des Bewusstseins, der Wahrnehmung, der Einstellungen und des Verhaltens pakistanischer Forscher in Bezug auf Open-Science-Konzepte. Die Ergebnisse offenbaren eine komplexe Open-Science-Landschaft in Pakistan, die sowohl von Optimismus als auch von erheblichen Herausforderungen geprägt ist. Open Science wird in erster Linie als Open Access, offene Forschungsdaten, offene Software, Zusammenarbeit und offene Methodik wahrgenommen und entspricht teilweise globalen Definitionen wie denen der UNESCO (2021) und von Fecher und Friesike (2014). Es bestehen jedoch weiterhin kritische Lücken im Bewusstsein umfassenderer Elemente wie Open-Science-Mandate, z. B. UNESCO-Empfehlungen, FAIR- und CARE-Prinzipien, Citizen Science, Vorregistrierung, offene Evaluierung und offene Infrastrukturen. Die Motivationen für die Ausübung von Open Science konzentrieren sich auf den freien Zugang und die Weitergabe wissenschaftlicher Erkenntnisse, die Verbesserung von Forschungsprozessen, gesellschaftliche Vorteile und wissenschaftliche Vorteile für Forscher und die Öffentlichkeit. Während Praktiken wie die Nutzung offener Bildungsressourcen und das Teilen von Methoden relativ weit verbreitet waren, blieben fortgeschrittenere Praktiken wie der offene Datenaustausch, offene Peer-Reviews, die Nutzung offener Infrastrukturen, Vorregistrierungen und Citizen Science zurück, was Trends aus anderen Ländern des Globalen Südens widerspiegelt. Teilnehmer aus verschiedenen Disziplinen erkannten das Potenzial von Open Science in Pakistan an, betonten aber auch vielfältige Hindernisse, darunter datenbezogene Probleme, finanzielle und infrastrukturelle Einschränkungen, mangelndes Bewusstsein für Open Science, begrenzte institutionelle und staatliche Unterstützung sowie ethische und soziale Bedenken.This research aims to understand the meaning and potential of open science in Pakistan, a country located in the Global South. The study particularly focuses on analyzing Pakistani researchers' awareness, perceptions, attitudes, and behaviors around open science concepts. The findings reveal a complex landscape of open science in Pakistan characterized by both optimism and significant challenges. It is primarily perceived as open access, open research data, open software, collaboration, and open methodology, aligning partially with global definitions such as those of UNESCO (2021) and Fecher and Friesike (2014). However, critical gaps remain in awareness of broader elements, such as open science mandates. e.g., UNESCO recommendations, FAIR and CARE principles, citizen science, pre-registration, open evaluation, and open infrastructures. Motivations for practicing open science are centered on free access and sharing of scientific knowledge, improving research process, societal benefits, and scholarly benefits for researchers and the public. While practices like using open educational resources and sharing methodologies were relatively common, more advanced practices like open data sharing, open peer review, use of open infrastructures, pre-registration, and citizen science lagged behind reflecting trends observed in other Global South contexts. Participants across disciplines acknowledged the potential of open science in Pakistan, but also highlighted multifaceted barriers, including data-related issues, financial and infrastructural constraints, lack of awareness about open science, limited institutional and governmental support in the shape of training and formal policies, and ethical and social concerns. Moreover, broader structural inequities in scholarly communication, such as epistemic injustice, research infrastructure and resource constraints further exacerbate these challenges, ultimately reinforcing disparities between the Global South and the North
SI-traceable total analysis of nitrate and nitrite by isotope dilution optical spectroscopy and its application to Berlin surface waters
No full textAccurate nitrate and nitrite data support water-quality regulation, yet routine methods rely on external calibration and rarely achieve SI traceability. We report a calibration-free determination of nitrate and nitrite by combining isotope dilution with high-resolution continuum-source graphite furnace molecular absorption spectrometry (ID-HR-CS-GF-MAS). A 15N-enriched nitrate spike (its concentration verified by reverse isotope dilution against the standard reference material NIST 3185) provides the SI link, and it is gravimetrically added to samples; nitrate and residual nitrite are converted in situ to nitric oxide (NO), whose 215 nm band is recorded at a pixel resolution of λ/Δλ ≈ 140 000. The 0.2127 nm shift between 14NO and 15NO electronic spectra is resolved, and a three-latent-variable partial least squares regression model yields the 15N/14N ratio with 0.3% precision. Instrumental LoD values of 4.8 ng (14N) and 3.2 ng (15N) translate to a method LoD of 4.8 ng of nitrogen (equivalent to 1.05 mg L−1 NO3− for a 20 μL aliquot). The furnace program allows for successive drying/pyrolysis loops, so additional 20 μL aliquots can be layered onto the graphite platform. Alternatively, a 10 mL anion-exchange solid-phase extraction step concentrates nitrate and nitrite fivefold, allowing for the analysis of even lower sample concentrations. Results for four certified reference materials (2.9 to 1000 mg L−1 NO3−) agreed with certified values, giving relative expanded uncertainties of 2 to 4%. Analysis of twenty Berlin surface-water samples revealed concentrations ranging from 0.10 to 7.3 mg L−1 NO3−, indicating that the Panke River and Teltow Canal are the primary sources of nitrogen. ID-HR-CS-GF-MAS thus delivers ID-MS-level accuracy in a few minutes per run with bench-top optics, and, with optional on-platform or SPE pre-concentration, extends SI-traceable nitrate/nitrite monitoring into the low-ng regime.Peer Reviewe
Future Caregiving Responsibilities, Employment Uncertainties, and Expected Childbearing Behavior: Survey Experimental Evidence from Germany
No full textIn societies experiencing declining birth rates, understanding factors that influence childbearing decisions is of interest. We used a factorial survey experiment to investigate how scenarios of future caregiving responsibilities toward aging parents and employment uncertainties shape the expected childbearing behavior of a fictitious couple. Respondents from the nationally representative German Socio-Economic Panel Innovation Sample (SOEP-IS) ( n = 1,750) were randomly assigned to five vignettes, each describing a hypothetical couple with varying levels of caregiving responsibilities towards an aging parent and employment uncertainties. Respondents subsequently rated their expectations about the hypothetical couple’s childbearing behavior within the next three years using an 11-point scale. Results show that high caregiving responsibilities and dual employment uncertainties reduce expected childbearing behavior by 2.8 and 1.9 units respectively, compared to when these are absent. The negative effect of high caregiving responsibilities is more pronounced among women, while respondents’ own caregiving and employment experiences do not moderate these effects. These results demonstrate how both future-oriented caregiving responsibilities and employment uncertainties alter expectations about family formation and highlight the scenarios that are regarded as more or less favorable for childbearing.Open Access funding enabled and organized by Projekt DEAL.Hertie School gGmbH (3104)Peer Reviewe
A scaling law for a model of epitaxially strained elastic films with dislocations
No full textA static variational model for shape formation in heteroepitaxial crystal growth is considered. The energy functional takes into account surface energy, elastic misfit-energy and nucleation energy of dislocations. A scaling law for the infimal energy is proven. The results quantify the expectation that in certain parameter regimes, island formation or topological defects are favorable. This generalizes results in the purely elastic setting from [ 23 ]. To handle dislocations in the lower bound, a new variant of a ball-construction combined with thorough local estimates is presented.Deutsche Forschungsgemeinschafthttp://dx.doi.org/10.13039/501100001659Peer Reviewe
Beeinträchtigung des Konzepts der Freiwilligkeit und Reproduktion sozialer Ungleichheiten durch die Teilnahme am Erwachsenenbildungsangebot zum Spracherwerb „Deutsch als Fremdsprache“
No full textIm Gegensatz zum Schulsystem, das durch Schulpflicht geprägt ist, basiert die Erwach-senenbildung auf freiwilliger Teilnahme. Diese Masterarbeit widmet sich dem schwer zu fassenden Konzept der Freiwilligkeit in diesem Kontext und untersucht es anhand einer qualitativen Forschung in Volkshochschulen und Familienzentren. Ziel der vorliegenden Arbeit ist es, eine für die Erwachsenenbildung geeignete Definition von Freiwilligkeit vor-zuschlagen. Diese Definition wurde zunächst theoretisch erarbeitet und anschließend in einer qualitativen Forschung weiterentwickelt. Sie beruht auf einem Dreier-Beziehungs-muster: einer individuellen, einer interpersonalen und einer strukturellen Beziehung. Die Arbeit stützt sich auf eine fundierte theoretische und gesellschaftliche Reflexion und bietet zudem eine historische Einordnung der Entwicklung der Erwachsenenbildung in Deutschland sowie der damit verbundenen Entstehung des Freiwilligkeitsprinzips. Die Ergebnisse der qualitativen Forschung verdeutlichen, welche Rolle Freiwilligkeit für die Teilnahme an Lernangeboten – exemplarisch im Bereich „Deutsch als Fremdsprache“ – spielt. Besonderes Augenmerk liegt dabei auf der Konstruktion des Habitus, der Rolle der Sprache sowie auf den sozialen und geschlechtsspezifischen Dimensionen des Sprach-erwerbs und deren Einfluss auf die Freiwilligkeit der Lernenden
Plasmodium proteins at the parasite-host interface contribute to the liver and blood infection stages
No full textPlasmodium-Parasiten gestalten ihre Wirtszellen umfassend um, um eine wachstumsfördernde Umgebung zu schaffen. Die Forschung zu Plasmodium-Wirt-Interaktionen konzentrierte sich bislang vor allem auf das Blutstadium von Plasmodium falciparum. Um ein breiteres Verständnis über verschiedene Plasmodium-Arten und Entwicklungsstadien zu erhalten, charakterisiert diese Arbeit sechs Kandidaten für exportierte Proteine im Nagetiermodell Plasmodium berghei. Die Auswahl erfolgte anhand vorhergesagter Exportsignale, evolutiver Konservierung und bekannter Assoziationen mit exportierten Proteinen. PBANKA_0100200 und PBANKA_1000300 tragen ein vorhergesagtes Plasmodium export element/host-targeting motif (PEXEL/HTS), wurden jedoch trotz Expression im Blutstadium nicht exportiert. Dies zeigt, dass dieses Motiv allein kein verlässlicher Marker für Proteinexport in P. berghei ist. PBANKA_0214600 wird während Leber- und Blutstadium exportiert und lokalisiert in diskrete zytoplasmatische Strukturen, die sich von Plasmodium berghei-induced membrane structures (IBIS) unterscheiden. Seine Deletion beeinträchtigte das Parasitenwachstum nicht, führte jedoch zu einer erhöhten Anzahl zirkulierender Schizonten, was auf eine Rolle bei der Sequestrierung hindeutet. Die tryptophanreichen Proteine IPIS2 und IPIS3 wurden mit dem IBIS-Protein IBIS1 immunopräzipitiert. Der Verlust von IPIS2 beeinträchtigte die Adhäsion von Schizonten an CD36 und reduzierte die Parasitenlast im Fett- und Lungengewebe, während IPIS3-Deletion lediglich zu erhöhten zirkulierenden Schizonten führte.
Schließlich wurde PbACS9, eine mutmaßliche Acyl-CoA-Synthetase, als exportiertes Protein an der Erythrozytenmembran identifiziert. PbACS9-defiziente Parasiten zeigten eine verzögerte Entwicklung im Leberstadium sowie erhöhte Gametozytenzahlen im Blutstadium.Plasmodium parasites extensively remodel their host cells to establish a growth-permissive environment. Research on Plasmodium–host interactions has largely focused on the blood stage of Plasmodium falciparum. To gain broader insights into parasite–host interfaces across species and life cycle stages, this thesis characterizes six candidate exported proteins in the rodent malaria model Plasmodium berghei. Candidates were selected based on predicted export signals, conservation across Plasmodium species, and association with exported proteins. Many exported proteins in P. falciparum possess a Plasmodium export element/host-targeting motif (PEXEL/HTS). Two candidates, PBANKA_0100200 and PBANKA_1000300, contain predicted PEXEL/HTS motifs but were not exported despite blood-stage expression, highlighting that this motif alone is not sufficient to predict protein export in P. berghei.
PBANKA_0214600 was shown to be exported during liver- and blood-stage infection and localizes to cytoplasmic structures distinct from Plasmodium berghei-induced membrane structures (IBIS). Although its deletion did not affect parasite growth, increased numbers of circulating schizonts suggest a role in sequestration. The tryptophan-rich proteins IPIS2 and IPIS3 were identified as IBIS-associated proteins. Loss of IPIS2 impaired schizont adhesion to CD36, leading to increased circulating schizonts and reduced parasite burden in adipose and lung tissue. In contrast, IPIS3 deletion increased circulating schizonts without affecting tissue sequestration. Finally, the putative acyl-CoA synthetase PbACS9 was exported to the erythrocyte membrane. PbACS9-deficient parasites displayed delayed liver-stage development and increased gametocyte numbers, while fatty acid uptake and metabolism of fatty acids shorter than 18 carbons remained unchanged