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Striving towards biodiversity conservation through collaboration of research and practice. Learnings from the Translational Centre Biodiversity Conservation
Item type: Other Journal Item
Buhler, Christoph; Richman, Sarah (2025)
Assessing the Impact of Heyndrickxia coagulans Administered Through Sugar-Free Chewing Gum on Dental Biofilm: A Double-Blind Randomized Controlled Trial
Item type: Journal Article
Cirio, Silvia; Mantegazza, Giacomo; Salerno, Claudia; et al. (2026)
Background: Heyndrickxia coagulans has emerged as a candidate for oral health applications, and chewing gum offers a promising delivery method. This study evaluates whether H. coagulans delivered via sugar-free chewing gum can induce detectable changes in plaque microbial ecology. Methods: A randomized, double-blind, placebo-controlled clinical trial was conducted on 52 healthy adults. Participants consumed probiotic or control gum for 4 weeks. Dental plaque was collected at baseline (T0), mid-intervention (T1), end of intervention (T2), and one week post-intervention (T3). qPCR quantified H. coagulans, while 16S rRNA gene profiling assessed microbial diversity and taxonomic composition. Statistical analyses included rank-based difference-in-differences models, Wilcoxon and Mann-Whitney tests, and differential abundance inference based on negative binomial modeling. Results: Forty-four subjects completed the study. In the Intervention group, the strain was detected in 71.4% of participants at T1 and 61.9% at T2, and it persisted in 9.5% at T3. Differential abundance analysis revealed a broad depletion of taxa linked to oral dysbiosis at T2 with partial persistence at T3, along with selective enrichment of beneficial strains. Conclusions: H. coagulans delivered via chewing gum can reach the dental biofilm and induce modest, transient shifts in microbial composition. However, these biofilm ecology findings should be interpreted in the context of clinical outcomes.
Single-Step Extrusion Printing of Microgrooved Annulus Fibrosus Scaffolds via Patterned Nozzles
Item type: Journal Article
Kluser, Nadine; Alig, Gion Ursin; Sprecher, Christoph; et al. (2026)
Intervertebral disk pathology, including disk herniation and degeneration, is a major contributor to chronic low back pain, and when conservative treatment fails, surgical management often involves discectomy-based procedures that leave residual annulus fibrosus (AF) defects associated with reherniation and progressive degeneration. These limitations have motivated interest in regenerative strategies using biomaterial scaffolds; however, reproducing the hierarchical, angle-ply architecture of the AF remains challenging. Here, we present a single-step extrusion-based 3D-printing approach to fabricate polycaprolactone (PCL) scaffolds with aligned microscale surface grooves that promote AF-like organization. Patterned nozzles with circumferential peaks generated uniaxial concave microgrooves (10-17 & micro;m wide) directly during printing, enabling formation of multilamellar angle-ply constructs. Human bone marrow-derived mesenchymal stem cells cultured on patterned scaffolds aligned longitudinally within concave grooves, forming end-to-end arrays that guided extracellular matrix deposition. Gene expression analysis showed that topographical cues governed cellular organization without significantly altering gene expression profiles, while TGF-beta 3 supplementation upregulated outer AF-associated markers, including COL1, COL12, SFRP2, MKX, MCAM, and SCX. TAGLN expression increased specifically on patterned scaffolds in the absence of TGF-beta 3, indicating an association between microgroove-guided cellular organization and TAGLN expression, warranting further investigation into potential tension-related mechanisms. This novel single-step extrusion-printing approach leverages custom nozzle geometry to impart concave microgrooves, facilitating scalable fabrication of multilamellar angle-ply scaffolds that induce aligned cellular organization and support potential applications in annulus fibrosus repair, as well as mechanobiological studies of anisotropic musculoskeletal tissues.
Primer of Strong-Field Quantum Electrodynamics for Experimentalists
Item type: Review Article
Kropf, Annabel; Schulthess, Ivo (2026)
This review serves as a conceptual and practical introduction to strong-field quantum electrodynamics (SFQED), written from the standpoint of experimental physicists. Rather than providing a comprehensive theoretical review, the paper focuses on the core ideas, terminology, and challenges in SFQED that are most relevant to experimental design and interpretation. The review serves as a first point of contact with the subject, bridging the gap between foundational theory and hands-on experimental investigations, and complementing more formal literature in the field.
Cross-national time series analysis of the association between population density and population health outcomes
Item type: Journal Article
Tang, Hoi Sze; Ko, Jeremy; Lee, Harry F. (2026)
This study examines the global association between population density and public health using data from 151 countries spanning 2000-2020. Drawing on two competing theoretical perspectives-the Malthusian view, which links population pressure to resource depletion and deteriorating health, and the Boserupian framework, which emphasizes innovation and adaptation-the analysis investigates how demographic concentration is associated with national health outcomes. Using a two-way fixed-effects panel model, the study estimates the association between population density and three key indicators-life expectancy, infant mortality, and under-five mortality-while controlling for socioeconomic and institutional factors. The results reveal a positive and statistically significant association between higher population density and improved health outcomes, particularly in developing countries, suggesting that demographic pressure can be associated with technological and institutional adaptation that enhances healthcare accessibility and efficiency. However, the study also notes that these global-level findings differ from subnational research reporting adverse health impacts in densely populated areas, largely due to differences in analytical scale and data aggregation. The findings underscore the importance of effective institutions and infrastructure planning in sustaining density-related health benefits. Future research should explore subnational and spatial mechanisms to unpack this macro-level "black box," examining how governance, the environment, and infrastructure mediate the density-health relationship.