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LAMP2A regulates endosomal protein composition and membrane identity in exosome biogenesis
No full textThe endolysosomal system maintains cellular homeostasis through protein degradation and the release of exosomes that mediate intercellular communication. LAMP2A, a transmembrane protein, has been implicated in selective cargo loading into exosomes, or eLLoC. Here, we investigated how LAMP2A influences endosomal protein composition and function using mass spectrometry of endosomal and exosomal fractions from human retinal pigment epithelial cells. Loss of LAMP2A changed Rab GTPase distribution, reduced cortical actin association, and shifted phosphoinositide dynamics, leading to enhanced endosomal acidification and maturation. These changes extended beyond the loss of proteins containing ExoSignals, the canonical targeting motifs, suggesting that LAMP2A contributes broadly to endosomal identity. Experimental validation confirmed that LAMP2A deficiency reprograms endosomal fate toward degradation while influencing exosome composition. These findings highlight a role for LAMP2A in coordinating membrane identity, endosomal maturation, and intercellular communication through exosomes, providing insights into mechanisms that couple endosomal remodeling with cellular signaling and clearance pathways.</p
Quantum metrics from length functions on quantum groups
No full textWe study the quantum metric structure arising from length functions on quantum groups and show that for coamenable quantum groups of Kac type, the quantum metric information is captured by the algebra of central functions. Using this, we provide the first examples of length functions on (genuine) quantum groups which give rise to compact quantum metric spaces.</p
Algorithmic profiling of the unemployed:A case study and a framework for understanding legitimization processes
No full textMachine learning-based algorithms (MLAs) are often criticized for being biased or unfair when used by public institutions to make predictions or decisions about people's lives, particularly when marginalized or disadvantaged groups are involved. In this context, an important topic is the role of public discourses on the legitimacy of these tools, as these can significantly impact such projects. However, research on this topic is sparse. To add to this knowledge, the present study conducts a longitudinal case study of a public Danish project involving the deployment of an MLA system for profiling unemployed citizens with respect to their risk of long-term unemployment. The system was used for around seven years, but after significant public criticism, it was eventually terminated. Through a grounded theory-based document analysis of the public discourse on the MLA system, a set of legitimization factors and themes is identified. Using these elements, it is shown that public criticism and justification do not only appeal to different principles of legitimacy but may concern different aspects of phenomena. Furthermore, the study demonstrates that legitimization aspects should not be considered in isolation, as these can be used to develop arguments related to other aspects, some of which are inclined to counter each other.</p
Variation of disability courses in Danish chiropractic patients with low back pain:a one-year cohort study with four follow-ups
No full textBACKGROUND: The clinical course of low back pain (LBP) is highly variable. While some recover quickly, others experience prolonged or fluctuating disability. Understanding this heterogeneity, and the factors that influences it, is important for effective clinical management and for communicating realistic prognosis to patients. The aims of this study were to describe the variation in disability courses among chiropractic patients with LBP and to investigate how selected biopsychosocial characteristics measured at baseline can predict these courses and potentially explain the observed variation.METHODS: Longitudinal data from 2,777 Danish adults consulting chiropractors for a new episode of LBP were analysed. Disability was measured at baseline, 2, 13, and 52 weeks using the Roland Morris Disability Questionnaire (0-100 scale). Latent Class Analysis was applied to identify disability trajectories. Associations between baseline patient characteristics and trajectory class membership were examined across demographic, psychological and social domains. A post hoc composite index score was developed to summarize the cumulative burden of unfavourable baseline characteristics.RESULTS: Nine distinct disability trajectories were identified, ranging from rapid recovery to persistent high disability, and fluctuating patterns. Six classes accounted for approximately 90% of patients, while three smaller classes with more irregular trajectories accounted for 10%. Higher number of MSK pain sites, comorbidities, and higher levels of BMI, depression, anxiety, kinesiophobia, prescription analgesic use, and poorer general health were associated with increased likelihood of belonging to less favourable trajectories. Both individual baseline characteristics and the index score combining these characteristics showed a clear dose-response relationship with disability trajectories. Patients with higher burden were more likely to follow less favourable trajectories. However, substantial variation remained within index groups, indicating that baseline characteristics alone cannot fully predict individual outcomes.CONCLUSION: Among chiropractic patients with LBP, trajectories of disability over one year can vary substantially in pattern. Baseline biopsychosocial characteristics influence trajectories and prognosis in a cumulative, dose-dependent manner. Clinicians should be aware of this variability and tailor communication about expectations accordingly.</p
Routine brain MRI in suspected lung cancer:clinical justification and diagnostic yield
No full textBackground: Lung cancer is the leading cause of cancer-related death worldwide. Brain metastases are common and associated with poor prognosis. While MRI is highly sensitive for detecting brain metastases, the clinical value of routinely adding up-front MRI to PET/CT during initial staging remains debated. This study focuses on suspected lung cancer patients, integrating workflow data (MRI waiting time, MDT availability) to evaluate up-front brain MRI and its impact on clinical decision-making. Methods: This retrospective cohort study included 183 patients with suspected lung cancer referred for up-front brain MRI at Odense University Hospital between March-August 2021. All patients underwent pre-diagnostic PET/CT, and brain MRI was performed in cases with suspected stage II-IV disease (TNM 8th edition). Results: Brain metastases were detected by MRI in 21/183 patients (11.5%), predominantly from primary lung cancer (n = 19, 90.4%). Among patients with confirmed lung cancer (n = 134), the prevalence was 14.2% (19/134), corresponding to a number needed to scan (NNS) of 7.1; across the full cohort, the NNS was 8.7. MRI led to upstaging to stage IV disease in 3/134 lung cancer patients (2.2%), resulting in a NNS of 44.7. PET/CT had a positive predictive value of 57.1% and a negative predictive value of 90.3%, indicating limited reliability detecting brain metastases. Conclusion: Routine up-front brain MRI identified brain metastases in a small but clinically relevant subset of patients, primarily those with signs of dissemination on initial PET/CT. A risk-stratified approach targeting high-risk groups may reduce MRI use without compromising detection, improving staging efficiency and resource allocation.</p
Using artificial neural networks for anomaly detection in infrared thermography images for rapid diagnosis in an emergency care unit
No full textInfrared thermography (IRT) has emerged as an affordable, rapid and noninvasive complement to widely adopted yet resource-demanding medical imaging techniques such as MRI, CT scans and X-rays, offering diverse applications in the medical field. While IRT hardware is well established and capable of providing high-quality thermographic images, the analysis of such images often requires well-trained experts. Current state-of-the art methods for computer-aided IRT analysis rely on statistical tests of temperature gradients between control points, which are suboptimal because they do not fully exploit the available information regarding spatial temperature distributions. This paper addresses this issue by incorporating artificial neural networks (ANN) into the IRT analysis workflow. We focused on a particular case in which the IRT was utilized in the emergency department (ED) for predicting 30-day mortality, thereby contributing to improved diagnosis and patient care in emergency medicine. In total, the IRT images of 214 patients were analyzed. Various ANN-based approaches were considered in this study, and the best results were obtained using an anomaly detection model based on a variational autoencoder (VAE), which achieved promising results for detecting abnormal images. This paper comprehensively presents all the analysis details as well as recommendations regarding image preprocessing, augmentation, and potential enhancements of the models.</p
Effect of Zoledronic Acid on Skeletal Muscle After Bariatric Surgery:A Secondary Analysis From a Randomized Controlled Trial
No full textOBJECTIVE: This study aimed to investigate whether a single infusion of 5 mg zoledronic acid, given before bariatric surgery to prevent bone loss, could also hinder the loss of muscle mass, strength, and physical function.METHODS: In this double-blinded study, patients referred for bariatric surgery were randomized 1:1 to either intervention (INT: single dose zoledronic acid 5 mg) or placebo (CON). Assessments were conducted at baseline and 12 months postoperatively. The outcomes were body composition (DXA), muscle strength for knee extensor (KE) and knee flexor (KF), and physical function.RESULTS: Fifty-nine patients (age: 48.9 ± 6.3 years, BMI: 42.3 ± 5.3 kg/m2) were allocated to INT (n = 31) or CON (n = 28). At 12 months, no between-group differences were observed in body weight, fat mass, or lean body mass. Both groups experienced ~14% loss of lean body mass. No between-group differences were observed for absolute or relative muscle strength. Absolute strength declined by 11%-18%, while relative strength improved by 10%-22%. No between-group differences were found in physical function measures, all of which improved by 5%-18%.CONCLUSIONS: A single infusion of 5 mg zoledronic acid did not prevent the loss of muscle mass or strength or improve physical function.TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04742010; EudraCT number: 2019-001650-26.</p
The Effect of an 8-Week Low- or High-Volume Protocol of the Adductor Strengthening Programme on Hip Adduction Strength in Female Football Players—A Randomized Trial
No full textThe aim of this study was to investigate if an 8-week high-volume protocol of the Adductor Strengthening Programme was more effective than a low-volume protocol in increasing and maintaining isometric hip adduction strength in female football players. We randomized 52 players from the Norwegian women's 1st and 2nd division to a low-volume (220 reps/side) or high-volume (394 reps/side) group. Both groups performed an 8-week protocol of the Adductor Strengthening Programme and a 10-week maintenance protocol with 1 session/week (16 reps/side/session). We measured isometric hip adductor torque (Nm/kg) in a long-lever squeeze test (at 0° and 15° hip abduction) using the ForceFrame at baseline, weeks 4, 6, 8, and 18. Both groups increased their isometric hip adduction strength over the 8-week period (low-volume 0°: 0.13 [95% CI: 0.07–0.20] Nm/kg, 15°: 0.22 [95% CI: 0.07–0.36] Nm/kg; high-volume 0°: 0.13 [95% CI: 0.04–0.22] Nm/kg, 15°: 0.31 [95% CI: 0.18–0.45] Nm/kg), with no between-group difference in either test position (0°: -0.01 [95% CI: −0.11-0.01] Nm/kg; 15°: 0.10 [95% CI: −0.09-0.29] Nm/kg). Also, both groups maintained their strength throughout the 10-week maintenance period, with no between-groups difference in either test position (0°: 0.12 [95% CI: −0.01-0.24] Nm/kg; 15°: 0.06 [95% CI: −0.11-0.23] Nm/kg). Our results indicate that an 8-week high-volume protocol of the Adductor Strengthening Programme was not more effective in increasing isometric adductor strength in female football players than a low-volume protocol. Both groups increased their strength over the 8-week training period and maintained their strength during the 10-week maintenance period. Trial registration: The study protocol was uploaded to Open Science Framework before unblinding and analyzing the data (https://osf.io/7xfw4/).</p
Two methods for clustering products in a sensory study:STATIS and ClusMB
No full textSensory experiments are essential for product characterization and development. One of the main objectives of these tasks is to highlight similarities and differences among the target products. For this purpose, cluster analysis of the products can be helpful in investigating the relationships among the products. To perform such an analysis, we propose two methods: a new original method named ClusMB, and one based on clustering on the STATIS axes. The methods are demonstrated in two case studies involving Check-All-That-Apply (CATA) and projective mapping, but can easily be extended to other methods producing multi-block data structures. A paradox is highlighted to show the importance of these new methods in overcoming the theoretical limitations of average or contingency tables. To aid the interpretation of the outcomes, insightful indices are provided to quantify subjects' agreement and contribution to the chosen clustering solution
Synthesis and Characterization of CuCo₂O₄ Nanostructures-Based Hybrid Nanofluids for Enhanced Heat Transfer Applications
No full textDet presserende behov for effektiv termisk styring i miniaturiserede og højtydende enheder har fremskyndet udviklingen af nanovæsker med forbedret termisk ledningsevne. Nanomateriale-baserede væsker kan tilbyde bedre varmeafledning end konventionelle kølemidler, men deres ydeevne afhænger i høj grad af nanopartiklernes struktur og suspensionens stabilitet. Spinel-struktureret CuCo₂O₄ tilbyder både termiske og strukturelle fordele, men dets potentiale, især i en kulstofmodificeret porøs form, er stadig stort set uudforsket. Denne afhandling undersøger kulstofmodificerede CuCo₂O₄-nanostrukturer somen ny klasse af hybride nanovæske-additiver med fokus på, hvordan kulstofindholdet påvirker deres mikrostruktur, overfladeegenskaber og termiske ydeevne. En rækkeCuCo₂O₄-nanostrukturer integreret med tilpassede kulstofkoncentrationer blev syntetiseret ved hjælp af hydrotermal metode og karakteriseret i detaljer ved hjælp af et omfattende sæt af strukturelle, kemiske og termiske analyseteknikker. Disse omfattede røntgendiffraktion, Raman-spektroskopi, røntgenspektroskopi, scanning- og transmissionselektronmikroskopi, Brunauer-Emmett-Teller-overfladearealanalyse, dynamisk lys-spredning, zeta-potentiale, termogravimetrisk analyse, differentiel scanning kalorimetri og operando synkrotron røntgenafbildning. Disse teknikker blev anvendt på en komplementær og sammenlignende måde. Strukturanalyse viste, at kulstof ikke indbygges i spinel-gitteret, menakkumuleres på overfladen samt ved korngrænsen i form af u ordnede kulstofrige domæner. Moderat tilsætning af kulstof, 5 mg og 10 mg (1-4 vægtprocent af den anvendte prækursor), forbedrede krystalliniteten, reducerede gitterspændingen og introducerede polære overfladegrupper såsom hydroxyl- og karbonatgrupper. Disse ændringer øgede det specifikke overfladeareal (op til 31,91 m²/g) og mesoporøsiteten, hvilket muliggjorde forbedret dispersionsstabilitet. Data fra dynamisk lys-spredning og zeta-potentiale bekræftede den kolloidale stabilitet, hvor prøven med 10 mg kulstof udviste et zeta-potentiale på +34,7 mV og en ensartet dispersion i vand. Test af termisk ledningsevne vistemarkante forbedringer ved ultralave nanopartikelkoncentrationer (0,05 vægtprocent). Nanovæsker baseret på 5 mg og 10 mg kulstofmodificeret CuCo₂O₄ opnåede termiske ledningsevner på henholdsvis 0,77 og 0,74 W/m·K, hvilket viste op til 20 % forbedring i forhold til den rene basisvæske. Denne forbedring tilskrives øget interfacialt overfladeareal, forbedret poretilgængelighed og mere effektiv phonontransport. Overdreven tilsætning af kulstof, 20 mg og 30 mg (4-10 vægtprocent), medførte poreblokering og partikelaggregering, hvilket resulterede i nedsat ydeevne. Operando synkrotron røntgenafbildning blev anvendt som proof of concept til at visualisere nanostrukturernes dispersion under flow. Afslutningsvis udviser de kulstofmodificerede CuCo₂O₄-nanostrukturer stabil dispersion og forbedret termisk ledningsevne ved minimale tilsætninger, hvilket gør dem til lovende additiver til avancerede nanovæsker. Dette arbejde etablerer en klar struktur–funktions-sammenhæng og giver en rationel designstrategi for høj-effektive kølesystemer til elektronik, mikrofluidik og vedvarende energiteknologier.The urgent demand for efficient thermal management in miniaturized and high-powerdevices has accelerated the development of nanofluids with enhanced thermal conductivity. Nanomaterials-engineered fluids can offer better heat dissipation than conventional coolants, but their performance depends heavily on nanoparticle structure and the stability of the suspension. Spinel-structured CuCo₂O₄ offers both thermal and structural advantages, yet its potential, particularly in carbon-modified porous form, remains largely unexplored. This thesis investigates carbon-modified CuCo₂O₄ nanostructures as a new class of hybrid nanofluid additives, focusing on how carbon content influences their microstructure, surface properties, and thermal performance. A series of CuCo₂O₄ nanostructures integrated with tailored carbon concentrations were synthesized via hydrothermal method and characterized in detail using a comprehensive set of structural, chemical, and thermal analysis techniques. This included X-ray diffraction, Raman spectroscopy, X-ray spectroscopy, scanning and transmission electron microscopy, BrunauerEmmett-Teller surface area analysis, dynamic light scattering, zeta potential, thermogravimetric analysis, differential scanning calorimetry, and operando synchrotron X-ray imaging. These techniques were applied in a complementary and comparative manner. Structural analysis showed that carbon does not incorporate into the spinel lattice but accumulates at the surface as well as at the grain boundaries in the form of disordered carbon-rich domains. Moderate carbon addition 5 mg and 10 mg (1-4 weight % of involved precursor) enhanced crystallinity, reduced lattice strain, and introduced polar surface groups such as hydroxyl and carbonate. These changes increased the specific surface area (up to 31.91 m²/g) and mesoporosity, enabling the improved dispersion stability. Dynamic light scattering and zeta potential data confirmed the colloidal stability, with the10 mg carbon sample exhibiting a zeta potential of +34.7 mV and uniform dispersion in water. Thermal conductivity tests revealed significant improvements at ultralow nanoparticle concentrations (0.05 wt%). Nanofluids based on 5 mg and 10 mg carbon-modified CuCo₂O₄ reached thermal conductivities of 0.77 and 0.74 W/m·K, respectively, showing up to 20% enhancement over the pure baseline. This improvement is attributed to increased interfacial surface area, enhanced pore accessibility, and more efficient phonon transport. Excessive carbon loading 20 mg and 30 mg (4-10 weight %) caused pore blockage and particle aggregation, resulting in diminished performance. Operando synchrotron X-ray imaging was used as a proof of concept to visualize nanostructure dispersion under flow. In conclusion, the carbon-modified CuCo₂O₄ nanostructures exhibit stable dispersion and enhanced thermal conductivity at minimal loadings, making them promising additives for advanced nanofluids. This work establishes a clear structure–function relationship and provides a rational design strategy for high-efficiency cooling systems for electronics, microfluidics, and renewable energy technologies.