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Investigating Phosphorus Abundances in a Sample of APOGEE-2 Bulge Globular Clusters
No full textPhosphorus-enhanced (P-rich; [P/Fe] ≳ +0.8) giants have been found among mildly metal-poor field stars, but in only one star in a globular cluster (GC), M4 (NGC 6121). Also, in a sample of bulge spheroid stars, some of them showed a moderate P enhancement in the range +0.5 < [P/Fe] < +1.0. In this paper we derive the P abundance of moderately metal-poor ([Fe/H] ≳ −1) GC stars, aiming to check if the phenomenon could be related to the unusual multiple stellar populations found in most GCs. Here we present the detection of moderately P-enhanced stars among two out of seven bulge GCs (Tonantzintla 1 and NGC 6316), with metallicities similar to those of the bulge-field P-rich stars. Using H-band high-resolution (R ∼ 22,500) spectra from the APOGEE-2 survey, we present the first high-resolution abundance analysis of [P/Fe] from the P I 16482.932 Å line in a sample of selected bulge GCs. We find that all P-rich stars tend to also be N-rich, which hints at the origin of P-rich stars as second-generation stars in GCs. However no other correlations of P and other elements are found, which are usually indicators of second-generation stars. Further studies with larger samples and comparisons with field stars will be needed before any firm conclusions are drawn
The physiological cost of leadership in collective movements
No full textIndividuals can gain substantial benefits from collective actions.1,2,3,4,5,6,7 However, collective behaviors introduce new challenges, like coordinating actions, maintaining cohesion, and meeting the needs of different individuals. When making collective movements, leaders are typically thought to gain disproportionate benefits through the choice of more beneficial resources3 and/or earlier access to resources.8 However, reaping these benefits can also come with costs. Attempting to influence group movements can increase energy expenditure4,9,10 and predation exposure.11,12 Moreover, leadership involves a process of negotiation in many animal groups. Within-group differences in directional preferences are typically resolved by some individuals initiating directional movements, after which they are either followed (if they are successful in leading) or return to the group (if they fail).13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30 By combining data on movement initiations (using whole-group global positioning system [GPS] tracking31) and individual heart rate (from implanted electrocardiogram [ECG] loggers) in wild vulturine guineafowl, we found significant increases in heart rate (and decreases in heart rate variability) during collective movements. Further, we found that attempting—and failing—to initiate directional movement was physiologically costly, especially for leadership attempts when consensus among group members was low and when potential leaders acted against the majority. The scale of these costs far outweighed those arising from increased movement speeds alone, suggesting that leadership can induce physiological stress, entailing increased energy expenditure and potential physiological damage. These results suggest that behaviors often thought beneficial to individuals (by influencing group behaviors) are also physiologically costly, representing a constraint on group-living and explaining why sometimes individuals opt out of contributing to leadership
Could extracts from spent mushroom materials transform reclaimed water quality? – A pilot study on pathogen suppression, antimicrobial chemical removal, and plant growth enhancement
No full textEfficient near-field ptychography reconstruction using the Hessian operator
No full textX-ray ptychography is a powerful and robust coherent imaging method providing access to the complex object and probe (illumination). Ptychography reconstruction is typically performed using first-order methods due to their computational efficiency. Higher-order methods, while potentially more accurate, are often prohibitively expensive in terms of computation. In this study, we present a mathematical framework for reconstruction using second-order information derived from an efficient computation of the bilinear Hessian and Hessian operator. The formulation is provided for Gaussian-based models, enabling the simultaneous reconstruction of the object, probe, and object positions. Synthetic data tests, along with experimental near-field ptychography data processing, demonstrate a ten-fold reduction in computation time compared to first-order methods. The derived formulas for computing the Hessians, along with the strategies for incorporating them into optimization schemes, are well-structured and easily adaptable to various ptychography problem formulations
Factors associated with poor prognosis in elderly biopsy-only glioblastoma patients
No full textPurpose: Glioblastoma (GBM) in elderly patients has a poor prognosis. About one-third of patients have impaired perioperative performance status (PS) and often excluded from clinical trials. Brain biopsy is the standard diagnostic approach when resection is not feasible. Previous studies on preoperative prognostic factors have mostly focused on resected patients. This study aimed to identify preoperative factors associated with reduced three-month survival and treatment incompletion in elderly biopsy-only patients, with the three-month endpoint reflecting early mortality and rapid disease progression that often prevents treatment completion. Methods: We retrospectively reviewed biopsy-only GBM patients aged > 65 years between 2017 and 2020. Preoperative prognostic factors were analyzed using logistic regression, and overall survival (OS) was estimated using Kaplan–Meier. Results: A total of 132 patients were included. Median OS was 4.6 months, and 50% completed treatment. Palliative treatment was given to 17% of patients (median OS 1.3 months). Poor PS (OR = 0.2), larger tumor volume (OR = 0.9), and central tumor location (OR = 0.3) were independently associated with reduced three-month survival. Poor PS was the only predictor of treatment incompletion (OR = 0.06); in this subgroup, The median OS was 1.6 months, with only one of 21 completing treatment. Conclusion: In elderly patients with biopsy-only GBM, poor preoperative PS, central tumor location, and larger tumor volume were significantly associated with reduced short-term survival. Patients with poor preoperative PS were also less likely to complete treatment. These findings may aid in counseling on the potential benefits of biopsy in this vulnerable group
Markers of bone turnover after 12 months of exercise in patients with chronic kidney disease 3–5 : a post-hoc analysis of RENEXC – a randomized controlled trial
No full textBackground: Bone and mineral disorders are common in patients with chronic kidney disease (CKD), leading to poor quality of life, high fracture risk, and increased morbidity and cardiovascular mortality. Parathyroid hormone (PTH) and bone-specific alkaline phosphatase (bALP) are frequently used to assess bone turnover, but markers such as procollagen type I N-terminal propeptide (intact PINP) and tartrate-resistant acid phosphatase isoform 5b (TRAP5b), which reflect bone formation and resorption, may provide more specific insights into bone remodeling. This study aims to investigate the effects of balance and strength exercises on bone turnover markers in patients with CKD not undergoing kidney replacement therapy. Methods: This study is a post-hoc sub-analysis of the RENEXC trial, a randomized controlled exercise intervention lasting 12 months. A total of 151 CKD stage 3–5 patients were randomly assigned to either strength or balance exercise, both combined with endurance exercise. Exercise intensity was monitored using the Borg Rating of Perceived Exertion scale. Bone turnover markers, including intact PINP and TRAP5b, were measured at baseline and after 12 months. Results: Over 12 months, within-group changes in bone turnover markers were not statistically significant. In the strength group, intact PINP showed a non-significant increase and TRAP5b a slight decrease, while in the balance group intact PINP tended to decrease and TRAP5b remained stable. After adjustment for baseline values, between-group differences at 12 months were small and non-significant for both markers. Overall adjusted means were 78.7 µg/L for intact PINP and 1.87 U/L for TRAP5b, with no significant effects of treatment group, sex, or CKD stage. Additionally, both exercise groups showed an increase in the proportion of patients with TRAP5b values indicative of low bone turnover, suggesting a possible protective effect on bone resorption. Conclusions: Neither strength nor balance exercise significantly altered bone turnover markers over 12 months in patients with CKD. Nonetheless, both interventions were associated with more participants exhibiting TRAP5b values consistent with low bone turnover, indicating a potential role in mitigating bone resorption. These findings warrant further investigation into the long-term effects of exercise on bone health in CKD, with a particular focus on the mechanisms underlying these responses. Trial registration: NCT02041156 at http://www.ClinicalTrials.gov. Date of registration January 20, 2014. Retrospectively registered
Digital Wellbeing and its Regulation for Children and Young People
No full textThis paper examines digital wellbeing as an evolving, mul-tifaceted concept shaped by technological design, data practices, and policy measures. Focusing on children and young people, it explores how digital wellbeing is governed through individual, platform, and government regulation. The technological dimension is foregrounded through well-being management tools such as screen-time dashboards, and apps that promote self-monitoring and mindfulness. These tools reveal tensions between self-regulation and manipulation, wellbeing and commercialization. Platform regulation highlights how interface and algorithmic design influence user behavior and wellbeing, while government policy seeks to implement more child-centric policies such as those in the EU Digital Services Act and Australia’s Chil-dren's Online Privacy Code. Across these domains, digital wellbeing emerges not simply as a matter of personal dis-cipline but as a structural and systemic issue embedded in the infrastructures of digital technology. Ensuring that digi-tal systems support rather than compromise young users’ wellbeing remains a defining societal challenge of the twen-ty-first century
From Strong to Weak Correlations in Breathing-Mode Kagome van der Waals Materials : Nb3(F, Cl, Br, I)8 as a Robust and Versatile Platform for Many-Body Engineering
No full textBy combining ab initio downfolding with cluster dynamical mean-field theory, we study the degree of correlations in monolayer, bilayer, and bulk breathing-mode kagome van der Waals materials Nb3(F, Cl, Br, I)8. Our new material-specific many-body model library shows that in low-temperature bulk structures the Coulomb correlation strength steadily increases from I to Br, Cl, and F, allowing us to identify Nb3I8 as a weakly correlated insulator whose gap is only mildly affected by the local Coulomb interaction. Nb3Br8 and Nb3Cl8 are strongly correlated insulators, whose gaps are significantly influenced by Coulomb-induced vertex corrections. Nb3F8 is a prototypical bulk Mott insulator whose gap is initially opened by strong correlation effects. Angle-resolved photoemission spectroscopy measurements comparing Nb3Br8 and Nb3I8 allow us to experimentally confirm these findings by revealing spectroscopic footprints of the degree of correlation. Our calculations further uncover how the thickness and the stacking affect the degree of correlations and predict that the entire material family can be tuned into correlated charge transfer or Mott-insulating phases upon electron or hole doping. Our magnetic property analysis based on our model parameter library additionally confirms that interlayer magnetic interactions likely drive the lattice phase transition to the low-temperature structures. The accompanying bilayer hybridization through interlayer dimerization yields magnetic singlet-like ground states in the Cl, Br, and I compounds. We further prove that all low-temperature compounds are dynamically stable and that electron-phonon coupling to the low-energy subspace is suppressed. Our findings establish Nb3X8 as a robust, versatile, and tunable class for van der Waals-based Coulomb and Mott engineering with a rich phase diagram and allow us to speculate on the symmetry-breaking effects necessary for the recently observed Josephson diode effect in NbSe2/Nb3Br8/NbSe2 heterostructures