1. Probing Iceland's dust-emitting sediments: : particle size distribution, mineralogy, cohesion, Fe mode of occurrence, and reflectance spectra signaturesAdolfo Gonzalez-Romero, Cristina González-Flórez, Agnesh Panta, Jesús Yus-Díez, Patricia Córdoba, Andrés Alastuey, Natalia Moreno, Konrad Kandler, Martina Klose, Roger N. Clark, 2024, izvirni znanstveni članek Opis: Abstract. Characterising the physico-chemical properties of dust-emitting sediments in arid regions is fundamental to understanding the effects of dust on climate and ecosystems. However, knowledge regarding high-latitude dust (HLD) remains limited. This study focuses on analysing the particle size distribution (PSD), mineralogy, cohesion, iron (Fe) mode of occurrence, and visible–near infrared (VNIR) reflectance spectra of dust-emitting sediments from dust hotspots in Iceland (HLD region). Extensive analysis was conducted on samples of top sediments, sediments, and aeolian ripples collected from seven dust sources, with particular emphasis on the Jökulsá basin, encompassing the desert of Dyngjunsandur. Both fully and minimally dispersed PSDs and their respective mass median particle diameters revealed remarkable similarities (56 ± 69 and 55 ± 62 µm, respectively). Mineralogical analyses indicated the prevalence of amorphous phases (68 ± 26 %), feldspars (17 ± 13 %), and pyroxenes (9.3 ± 7.2 %), consistent with thorough analyses of VNIR reflectance spectra. The Fe content reached 9.5 ± 0.40 wt %, predominantly within silicate structures (80 ± 6.3 %), complemented by magnetite (16 ± 5.5 %), hematite/goethite (4.5 ± 2.7 %), and readily exchangeable Fe ions or Fe nano-oxides (1.6 ± 0.63 %). Icelandic top sediments exhibited coarser PSDs compared to the high dust-emitting crusts from mid-latitude arid regions, distinctive mineralogy, and a 3-fold bulk Fe content, with a significant presence of magnetite. The congruence between fully and minimally dispersed PSDs underscores reduced particle aggregation and cohesion of Icelandic top sediments, suggesting that aerodynamic entrainment of dust could also play a role upon emission in this region, alongside saltation bombardment. The extensive analysis in Dyngjusandur enabled the development of a conceptual model to encapsulate Iceland's rapidly evolving high dust-emitting environments.
Ključne besede: mineral dust, high-latitude dust, Icelandic dust, aerosol particles
Objavljeno v RUNG: 29.11.2024; Ogledov: 91; Prenosov: 0
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2. Functional characterisation of surfactant protein A as a novel prophylactic means against oncogenic HPV infectionsSinead Carse, Tim Reid, Jens Madsen, Howard Clark, Artur Kirjakulov, Martina Bergant Marušič, Georgia Schäfer, 2024, izvirni znanstveni članek Opis: Human papillomavirus (HPV) infection poses a significant health challenge, particularly in low- and middle-income countries (LMIC), where limited healthcare access and awareness hinder vaccine accessibility. To identify alternative HPV targeting interventions, we previously reported on surfactant protein A (SP-A) as a novel molecule capable of recognising HPV16 pseudovirions (HPV16-PsVs) and reducing infection in a murine cervicovaginal HPV challenge model. Building on these findings, our current study aimed to assess SP-A’s suitability as a broad-spectrum HPV-targeting molecule and its impact on innate immune responses. We demonstrate SP-A’s ability to agglutinate and opsonise multiple oncogenic HPV-PsVs types, enhancing their uptake and clearance by RAW264.7 murine macrophages and THP-1 human-derived immune cells. The SP-A opsonisation of HPV not only led to increased lysosomal accumulation in macrophages and HaCaT keratinocytes but also resulted in a decreased infection of HaCaT cells, which was further decreased when co-cultured with innate immune cells. An analysis of human innate immune cell cytokine profiles revealed a significant inflammatory response upon SP-A exposure, potentially contributing to the overall inhibition of HPV infection. These results highlight the multi-layered impact of SP-A on HPV, innate immune cells and keratinocytes and lay the basis for the development of alternative prophylactic interventions against diverse HPV types.
Ključne besede: surfactant protein A, SP-A, human papillomavirus, HPV, pseudovirus, cervical cancer, HPV prophylactic, low- and middle-income countries, LMIC
Objavljeno v RUNG: 22.07.2024; Ogledov: 873; Prenosov: 9
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3. Multiwavelength observations of the extraordinary accretion event AT2021lwxP. Wiseman, Y. Wang, S. Hönig, N. Castro-Segura, P. Clark, C. Frohmaier, M. D. Fulton, Giorgos Leloudas, M. D. Fulton, Tanja Petrushevska, 2023, izvirni znanstveni članek Ključne besede: accretion, accretion discs, tidal disruption events, transients, galaxies, supermassive black holesc
Objavljeno v RUNG: 15.05.2023; Ogledov: 1991; Prenosov: 5
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