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Dual-energy x-ray absorptiometry derived body composition trajectories across adulthood: reference values and associations with body roundness index and body mass index
Full text linkBackground
Population-specific reference values are needed to accurately contextualise age-related changes in body composition. This study aimed to a) establish age- and sex-specific reference values and cut-points for a range of dual-energy x-ray absorptiometry (DXA) derived metrics of lean mass (LM), fat mass (FM) and bone mineral density (BMD), across adulthood in a large adult cohort; and b) determine the association between DXA-derived body composition, body roundness index (BRI), and body mass index (BMI).
Methods
Cross-sectional data were collected from 10033 men and women aged from 18-92 years. Whole-body DXA scans were performed, and a range of metrics were calculated for LM (total LM, arm LM, leg LM, appendicular lean mass: ALM, skeletal muscle index: SMI), FM (total FM: kg and %, FMI, android to gynoid: A/G ratio) and bone (BMD). Cut-points equivalent to Z-scores of 1.0 - 2.5 SDs from the mean of a young reference population were established for each body composition metric.
Results
Detailed age- and sex-specific percentile curves were generated using the LMS method. Metrics of LM, central adiposity and BMD were higher in men, compared to women, whereas metrics of general FM accumulation were higher in women, compared to men. In both sexes, all LM metrics remained broadly stable during early and middle adulthood, after which progressively lower quantities were shown, whereas progressively higher FM metrics were shown from early adulthood through to late adulthood. In men, BMD was broadly stable across adulthood, whereas in women, markedly lower BMD was observed from the fifth decade of life. Significantly higher quantities of LM were shown across BMI categories, but not across BRI categories. The BRI was better correlated with FM%, FMI, and A/G ratio, compared to the BMI.
Conclusion
The reference values presented herein may support the interpretation of body composition in public health settings and the identification of people who may benefit from intervention to improve musculoskeletal and metabolic health. The BRI better reflects DXA-derived body composition and may provide screening utility beyond that of the BMI
Disease-free survival as surrogate for overall survival in esophageal cancer: An individual patient data meta-analysis of neoadjuvant chemotherapy and chemoradiotherapy
No full textBackground: The use of surrogate endpoints may expedite the reporting of study outcomes of clinical trials. The validity of disease-free survival (DFS) as a surrogate for overall survival (OS) in the neoadjuvant treatment of esophageal (E) or gastroesophageal junctional (GEJ) carcinomas remains uncertain. Objective: To evaluate DFS as a surrogate end-point for OS in E/GEJ using the meta-analytical approach DESIGN, SETTING, AND PARTICIPANTS: individual patient data from an international meta-analysis on operable locally advanced E/GEJ, which including randomized trials comparing at least two of the neo-adjuvant treatment strategies: upfront surgery (S), chemotherapy followed by surgery (CS), and/or chemoradiotherapy followed by surgery (CRS). Main outcomes and measures: Individual (Kendall's tau) and trial-level (R2) correlations between DFS and OS were estimated using a Clayton copula. Results: DFS and OS data were available for a total of 4518 pts: 2222 pts included in CS vs S, 1908 pts in CRS vs S, and 388 in CS vs CRS comparisons. 3440 patients had a DFS event and 3303 patients died. Kendall's tau was 0.73 [95 % CI 0.71 - 0.75] and R2 trial-level correlation was 0.95 [0.84 - 0.99] for CS vs S, Kendall's tau was 0.76 [0.74 - 0.77] and R2 was 0.96 [0.87 - 0.99] for CRS vs S, Kendall's tau was 0.87 [0.78 - 0.92] and R2 was 0.93 [0.43 - 1] for CRS vs CS. In a multistate model, the median time in the recurrence state was shorter in older vs more recent trials: mean time of 10.8 [10.2 - 11.4] vs 16.5 months [15.4-17.6]. Conclusions and relevance: DFS is a validated surrogate endpoint for OS in trials evaluating neoadjuvant chemotherapy or chemoradiotherapy in E/GEJ. DFS may be more useful as an endpoint when delays between recurrences and death become larger
Harnessing Winery and Distillery By-Products with Aspergillus oryzae: Potential for development of innovative fungi-based fermented food and feed
Full text linkWinery and distillery by-products, such as grape marc (GM), pre-distillation lees (PRE), and post-distillation lees (POST), pose environmental challenges due to their high chemical oxygen demand (COD). However, these by-products represent an underutilized resource with significant potential to contribute to sustainability. This study investigates the biovalorization of these by-products through the cultivation of the edible filamentous fungus Aspergillus oryzae to produce protein-rich fungal biomass via aerobic submerged fermentation. Hydrothermally pretreated and filtered substrates were used as liquid cultivation media at concentrations of 4% GM (w/v), 50% PRE (v/v), and 10% POST (v/v). The effect of these substrates on fungal growth was assessed by analyzing protein, amino acids (AAs), mineral, and polyphenol content, alongside COD. The results showed that A. oryzae biomass had enhanced protein content (29.4–55.6%), approximately twice that of the substrates, following the order 50% PRE > 4% GM > 10% POST. Total AAs ranged from 10.9% to 28.5% dry weight, with leucine and lysine as the dominant essential AAs. The fungal biomass was rich in minerals such as phosphorus (132.4–175.4 mg/100 g), magnesium (13.4–14.1 mg/100 g), and iron (3.76–4.57 mg/100 g), and contained total polyphenols ranging from 7.54 to 36.2 mg gallic acid equivalent/g biomass. Additionally, the process achieved a COD reduction of 46–79%, mitigating the environmental impact of these by-products. This approach highlights the potential of transforming these by-products into high-quality protein, providing new opportunities for innovative applications in food and feed production, while promoting sustainable food systems within circular bioeconomy framework
A Design Method for Graded Density Components by Polylactic Acid Foaming via Material Extrusion
No full textThe availability of foaming materials with properties that vary according to the heat transferred to the filament in the fused filament fabrication (FFF) process provides the opportunity to develop new design methodologies that allow the exploitation of the range of characteristics offered by these materials. In this work, an integrated CAD-CAM method to realize graded density foamed components via FFF is proposed. The method consists in the post-processing of a G-code file obtained from a CAD model according to functional requirements defined by a density map volumetric model. The method relies on the material property-process parameters correlation to drive the foaming in a specific extruder configuration. The temperature effect on extrusion width and density is experimentally investigated as the primary process parameter driving the foaming behaviour of a commercially available filament. Based on the density map of the volumetric model and the experimental characterization, temperature and extrusion amount are updated in the G-code file. The method is applied to a simple buoyant 3D shape to ensure its orientation in water
The discontinuity-enriched finite element method for multiple intersecting discontinuities
Full text linkWe extend the Discontinuity-Enriched Finite Element Method (DE-FEM) to simulate intersecting discontinuities, such as those encountered in polycrystalline materials, multi-material wedge problems, and branched cracks. The proposed hierarchical enrichment functions capture weak and strong discontinuities at junctions within a single formulation. Several numerical applications to branched cracks and polycrystalline microstructures under both thermal and mechanical loads are presented to demonstrate the proposed method. Results indicate that DE-FEM can accurately capture complex discontinuous primal and gradient fields and attain convergence rates comparable to those of standard FEM using fitted meshes. The main advantages of DE-FEM equipped with the proposed junction enrichment functions lie in the method's ability to model intersecting discontinuities using meshes that are completely decoupled from them and its robustness in reproducing correct displacement and strain jumps across them,..
They don’t really care about us: the impact of perceived vertical pay disparity on employee well-being
Full text linkThe gap in pay between those at the top of organizations and other organizational members continues to grow. In this paper, we tested the link between the perception of this vertical pay gap and people’s well-being at work. Specifically, we tested whether greater perceptions that pay is unequally distributed couples with people’s feelings that they are not valued (Lind & Tyler, 1988), eroding their sense of identification and well-being. In two cross-sectional surveys, Study 1a and 1b (N = 1335), we found that the more US and Italian workers perceived that there was a large vertical pay gap at work, the greater their tendency to feel that their organization was not concerned about their welfare. They were also less satisfied in their jobs and less likely to identify with their organization. In two pre-registered experiments, Study 2a and 2b (Ntotal = 785), we manipulated the vertical pay gap in hypothetical organizations and found that when the pay gap was large (versus small) participants felt that the organization was less concerned about their welfare. They also expected to be less satisfied in their jobs, to identify less with the organization, and to experience greater work-life interference
Hydraulic Properties of a Rock‐Soil‐Root System: Insights From Fraxinus ornus L. Saplings Growing on Different Carbonate Rocks
Full text linkDrought impacts trees in varied temporal and spatial patterns, suggesting that heterogeneity of below-ground water stores influences the fate of trees under water stress. Karst ecosystems rely on shallow soil overlying bedrock that can store available water in primary pores. A contribution of rock moisture to tree water status has been previously demonstrated, but actual mechanisms and rates of rock-to-root water delivery remain unknown. We report accurate measurements of hydraulic properties of two rock types (Breccia and Dolostone), of typical Karst red soil, and of roots of a common Karst tree species grown under different rock-soil combinations. Experimental data were used to build a water exchange model that supported the hypothesis that roots can extract water from porous and highly conductive rocks (Breccia), but not from more compact ones (Dolostone), especially when plants grow in rocky substrate or experience water stress, and thus have low root hydraulic conductivity and low rates of water extraction from rocks. Our data support the hypothesis that rocks represent important water stores for plants growing in rock-dominated habitats. Heterogeneous rock properties translate into different rates of water delivery to root systems, underlying complex patterns of tree mortality under severe drought stress
Photocatalytic Semi-Hydrogenation of Acetylene to Polymer-Grade Ethylene with Molecular and Metal–Organic Framework Cobaloximes
Full text linkThe semi-hydrogenation of acetylene in ethylene-rich gas streams is a high-priority industrial chemical reaction for producing polymer-grade ethylene. Traditional thermocatalytic routes for acetylene reduction to ethylene, despite progress, still require high temperatures and high H2 consumption, possess relatively low selectivity, and use a noble metal catalyst. Light-powered strategies are starting to emerge, given that they have the potential to use directly the abundant and sustainable solar irradiation, but are ineffective. Here an efficient, >99.9% selective, visible-light powered, catalytic conversion of acetylene to ethylene is reported. The catalyst is a homogeneous molecular cobaloxime that operates in tandem with a photosensitizer at room temperature and bypasses the use of non-environmentally friendly and flammable H2 gas feed. The reaction proceeds through a cobalt-hydride intermediate with ≈100% conversion of acetylene under competitive (ethylene co-feed) conditions after only 50 min, and with no evolution of H2 or over-hydrogenation to ethane. The cobaloxime is further incorporated as a linker in a metal–organic framework; the result is a heterogeneous catalyst for the conversion of acetylene under competitive (ethylene co-feed) conditions that can be recycled up to six times and remains catalytically active for 48 h, before significant loss of performance is observed
Caratterizzazione di strutture proteiche ripetute nella rivoluzione di AlphaFold
No full textFor the past fifty years, one of the greatest challenges in bioinformatics has been answering the question: "How can we predict the three-dimensional structure of a protein from its amino acid sequence?”. Experimentally determining the three-dimensional structure of a protein is often a slow and challenging process. Instead, sequencing its amino acids has become a high-throughput task thanks to advancements in technology and reduced costs. This disparity has led structural biology and bioinformatics to focus primarily on globular proteins, which reliably fold into a consistent three-dimensional structure and are therefore more accessible to computational and experimental studies. This focus aligns with the sequence-structure-function paradigm that has long guided our understanding of protein function. However, many proteins belong to the lesser-studied category of Non-Globular Proteins (NGPs), which display more diverse structural and functional characteristics, making them harder to observe.
The introduction of cutting-edge protein structure prediction algorithms like AlphaFold2 and RoseTTAFold has revolutionized the field. These algorithms demonstrated remarkable accuracy in the 14th edition of the CASP competition held in 2020, sparking what is often referred to as the AlphaFold revolution. Today, computational models of protein structures are available for nearly every known protein, significantly accelerating research in structural biology.
Despite this progress certain classes of NGPs, including Tandem Repeat proteins, pose unique challenges in terms of detection and classification. This work focuses on STRPs, a subset of TR proteins with well-defined structural features. The AlphaFold revolution has prompted major updates to databases that store structural data, such as RepeatsDB, which specializes in STRPs. This thesis outlines the evolution of RepeatsDB from its 3rd version in 2021 to its 4th version in 2024, showcasing improvements in manual curation, automated prediction, and scalability in response to the surge of available structural data.
RepeatsDB 4 introduces enhancements to the manual curation process through the development of the RepeatsDB Bio-curation Tool, which has helped refine the definition and classification of STRPs. In collaboration with Pfam, manually collected STRPs have been compared between the two databases, validating and improving the information held in both. The addition of automated prediction methods, such as the newly developed STRPsearch algorithm, represents another significant step forward. STRPsearch integrates curated STRP data with the fast structural search capabilities of FoldSeek to improve and speed up predictions, allowing RepeatsDB to scale and eventually cover the entire AlphaFoldDB.
Furthermore, reengineering RepeatsDB 4 has generated various side products, including the ngx-mol-viewers Angular library, which enhances biological molecule visualization and has already been included in other databases like MobiDB. Moreover, RepeatsDB 4 utilizes a specialized pipeline to enrich biological data by integrating external resources and software. The pipeline has been designed to be executed on a High Performance Computing (HPC) cluster environment via the DRMAAtic library for efficient cluster communication. The architecture of RepeatsDB 4 is designed to be reusable across other projects, such as the DOME registry, underscoring its broader applications in bioinformatics
The ESW of Wikidata: Exploratory search workflows on Knowledge Graphs
Full text linkExploratory search on Knowledge Graphs (KGs) arises when a user needs to understand and extract insights from an unfamiliar KG. In these exploratory sessions, the users issue a series of queries to identify relevant portions of the KG that can answer their questions, with each query answer informing the formulation of the next query. Despite the widespread adoption of KGs, the needs of current KG exploration use cases are not well understood. This work presents the “Exploratory Search Workflows” (ESW) collection focusing on real-world exploration sessions of an open-domain KG, Wikidata, conducted by 57 M.Sc. Computer Engineering students in two advanced Graph Database course editions. This resource includes 234 real exploratory workflows, each containing an average of 45 SPARQL queries and reference workflows that serve as gold-standard solutions to the proposed tasks. The ESW collection is also available as an RDF graph and accessible via a public SPARQL endpoint. It allows for analysis of real user sessions, understanding query evolution and complexity, and serves as the first query benchmark for KG management systems for exploratory search