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Time-integrated Southern-sky Neutrino Source Searches with 10 yr of IceCube Starting-track Events at Energies Down to 1 TeV
Get PDFIn the IceCube Neutrino Observatory, a signal of astrophysical neutrinos is obscured by backgrounds from atmospheric neutrinos and muons produced in cosmic-ray interactions. IceCube event selections used to isolate the astrophysical neutrino signal often focus on the morphology of the light patterns recorded by the detector. The analyses presented here use the new IceCube Enhanced Starting Track Event Selection (ESTES), which identifies events likely generated by muon–neutrino interactions within the detector geometry, focusing on neutrino energies of 1–500 TeV with a median angular resolution of 1.4 ° . Selecting for starting-track events filters out not only the atmospheric-muon background but also the atmospheric-neutrino background in the southern sky. This improves IceCube’s muon–neutrino sensitivity to southern-sky neutrino sources, especially for Galactic sources that are not expected to produce a substantial flux of neutrinos above 100 TeV. In this work, the ESTES sample was applied for the first time to search for astrophysical sources of neutrinos, including a search for diffuse neutrino emission from the Galactic plane. No significant excesses were identified from any of the analyses; however, constraining limits are set on the hadronic emission from TeV gamma-ray Galactic plane objects and models of the diffuse Galactic plane neutrino flux
Validating treat-to-target endpoints in childhood lupus: data-driven sensitivity analyses from the UK JSLE cohort study
Get PDFObjectives: To conduct data-driven sensitivity analyses to evaluate whether refined definitions of childhood-onset systemic lupus erythematosus (cSLE) treat-to-target goals provide better protection against moderate-severe flares and new damage, compared with original consensus-derived targets. Methods: The UK JSLE Cohort Study was utilized. Childhood-SLE target attainment was determined at each visit. Removal or transformation of cSLE target criteria (‘variations’) were investigated, for Childhood Lupus Low Disease Activity State (cLLDAS), cSLE Clinical Remission on Steroids (cCR) and cSLE Clinical Remission off Steroids (cCR-0). The impact of such variations on the hazards of subsequent moderate-severe flare and new damage was assessed, using Prentice–Williams–Peterson (PWP) models. Two-sided t-tests compared the hazard ratios (HRs) obtained from the PWP gap-time models for the original and varied cSLE target definitions. Results: Two variations of cLLDAS demonstrated significantly better protection against moderate-severe flare, including transformation of SLEDAI-2K cut-off to ≤3 (HR 0.13 [0.09, 0.19], P 0.05). A modified version of cLLDAS, combining these two transformations was also assessed, demonstrating further improvement in protection against moderate-severe flare (HR 0.12 [0.08, 0.17], P < 0.001). Conclusions: Refining the cLLDAS definition by lowering the SLEDAI-2K cut-off to ≤3 and PGA to ≤0.25 may enhance protection against moderate-severe flare, but not new damage. No variations of cCR or cCR-0 showed significant improvement
Dataset for Controlled polymerization catalysis for the synthesis of degradable amphiphilic polycarbonates from CO2
No full textData supporting the experiments described in the above manuscript
Design and characterisation of MgB2 bulk superconducting magnets containing Y2O3 and Mg additions
Get PDFThe aim of this thesis was to investigate new processing methods and powder treatments (prior to consolidation) in order to manufacture MgB2 bulk specimens with improved superconducting properties. The initial idea was to transpose a successful concept used for improving the mechanical properties of steels and superalloys to superconductors. In the 1970s, a new concept, known as Oxide Dispersion Strengthening (ODS), was explored to improve the mechanical properties at high temperature of nickel superalloys. The process aimed to create a fine dispersion of stable oxide (usually Y2O3) precipitates in a metallic matrix. In structural alloys, these precipitates effectively pin the dislocations and grain boundaries, leading to improved high temperature strength. The main objective of this work was to investigate if the ODS concept can be successfully applied to MgB2 bulk superconductors. In this case, the nano precipitates need to act as effective pinning centres for magnetic flux vortices to improve the superconducting properties, in contrast with conventional ODS materials in which they pin dislocations. The first chapter starts with an introduction on superconductivity, followed by a brief review of MgB2 literature. The concept of sintering is then introduced, followed by a description of the Field Assisted Sintering Technique (FAST). Finally, articles studying the manufacture of MgB2 bulks by FAST are discussed, before introducing relevant papers on the main types of MgB2 modifications: carbon doping, oxide and metallic additions and ball milling. The second chapter details the processing equipment and manufacturing routes used to produce the specimens studied in this work. It also introduces the different characterisation techniques and data analysis performed to extract material parameters. The three results and discussion chapters are presented in order of increasing complexity to gradually build up understanding of the relationship between processing parameters, microstructure and superconducting properties. Chapter 3 is dedicated to the characterisation of MgB2 bulks made from unmodified powder and sintered by FAST at temperatures ranging from 900 to 1200 °C. Chapter 4 first introduces the ODS process developed in this work and the analyses performed on ODS powders, then discusses the consolidation of these powders and the characterisation of ODS MgB2 bulks. Chapter 5 explores a new liquid phase/reactive sintering process I developed to improve the densification of MgB2 at lower processing temperatures. The process is first described, followed by the characterisation of Mg-MgB2 bulks made from MgB2 powders containing Mg additions. Chapter 5 ends on the concept of Mg-Y2O3-MgB2 composite bulks and investigates if these two additions can work in synergy to produce high performance composite superconductors
Resolved H ii Regions in NGC 253: Ionized Gas Structure and Suggestions of a Universal Density–Surface Brightness Relation
Get PDFWe use the full-disk Very Large Telescope/MUSE mosaic of NGC 253 to identify 2492 H ii regions and study their resolved structure. With an average physical resolution of 17 pc, this is one of the largest samples of highly resolved spectrally mapped extragalactic H ii regions. Regions of all luminosities exhibit a characteristic emission profile described by a double Gaussian with a marginally resolved or unresolved core with radius < 10 pc surrounded by a more extended halo of emission with radius = 20–30 pc. Approximately 80% of the emission of a region originates from the halo component. As a result of this compact structure, the luminosity–radius relations for core and effective radii of H ii regions depend sensitively on the adopted methodology. Only the isophotal radius yields a robust relationship in NGC 253, but this measurement has an ambiguous physical meaning. We invert the measured emission profiles to infer density profiles and find central densities of ne ≈ 10–100 cm−3. In the brightest regions, these agree well with densities inferred from the [S ii] λλ6716, 6730 doublet. The central density of H ii regions correlates well with the surface brightness within the effective radius. We show that this same scaling relation applies to the recent MUSE + Hubble Space Telescope catalog for 19 nearby galaxies. We also discuss potential limitations, including completeness, impacts of background subtraction and spatial resolution, and the generality of our results when applied to other galaxies
Enablers of successful dissemination of uncommon practices in positive deviance studies for nutrition: A scoping review
Get PDFBackground: The positive deviance approach identifies uncommon yet successful practices within communities to address malnutrition through context-specific solutions. While it identifies locally effective practices, a critical gap remains in understanding how these practices are translated into structured interventions for broader dissemination. This scoping review aimed to identify key enablers in positive deviance nutrition interventions that support the transition from identifying positive deviant practices to their active dissemination through structured interventions. Methods: We conducted a systematic search across five electronic databases (PubMed, Web of Science, PsycINFO, Science Direct, CINAHL) and grey literature. We included original research of all study designs published in English from January 1st, 1990, to December 2, 2024. Then, we conducted a narrative synthesis to account for heterogeneity among the studies. Results: Out of 259 positive deviance studies, 13 identified and then disseminated uncommon but successful practices. Among these, twelve studies included comparison groups and demonstrated improved nutrition outcomes. We identified six overarching themes that capture the key enablers of effective dissemination: integration with existing programs, ongoing capacity and skill building, active participant engagement, adaptable and modifiable practices and activities, cost-effective strategies, and cross-sectoral collaboration and partnership. Conclusion: This scoping review identified six themes that summarize enablers for effectively disseminating uncommon yet successful practices. These enablers not only align with successful criteria for scaling up conventional interventions but also reflect the principles of positive deviance. They highlight the value of integrating local knowledge and resources with external efforts to design tailored approaches to tackling malnutrition. Cross-sectoral collaboration and partnerships emerged as particularly important for scaling interventions. However, these enablers alone may not guarantee success, highlighting the need for future research to explore additional facilitators and barriers to optimize long-term implementation of positive deviance interventions in nutrition. Protocol registration: CRD42020180396
Cumulative oesophageal dose and risk of high-grade toxicity in thoracic re-irradiation: a dose/toxicity analysis
Get PDFBackground and purposeRe-irradiation (re-RT) in recurrent thoracic cancer is being performed more often and can cause severe toxicity. Information is lacking on safe re-irradiation dose constraints. We modelled the relationship between cumulative oesophageal dose and grade 3 or worse (≥G3) oesophageal toxicity to develop dose constraints.Materials and methodsWe performed a literature search for reports of thoracic re-RT and selected studies that quoted cumulative oesophageal maximum dose (cDmax) in equivalent dose in 2 Gy fractions (EQD2) and ≥G3 toxicity. Additional collected data were inter-treatment interval and concurrent chemotherapy use (conCT) at re-irradiation. Logistic regression analyses were performed. The models were used to predict the cDmax associated with a 5% ≥G3 toxicity rate. Model performance was assessed using the Pearson correlation coefficient (PCC).ResultsWe identified 21 studies (505 patients), with 49 ≥G3 toxic events. The median oesophageal cDmax and interval were 84.8 Gy3 (3.7 - 220.6 Gy3 EQD2) and 15.5 months (1-162) respectively. Use of conCT and oesophageal cDmax were significantly associated with toxicity on univariable and multivariable modelling (both p < 0.001). The maximum likelihood doses associated with 5% risk of ≥G3 toxicity with/without chemotherapy were cDmax 43.0 Gy3 (95% CI: -18.5, 108.8) and 94.2 Gy3 (95% CI: 79.6, 142.8) respectively. The model had a PCC of 0.75 (p = 0.013) suggesting good correlation to the dataset.ConclusionThe models predict a 5% toxicity at cDmax 43.0 Gy3 and 94.2 Gy3 EQD2 with/without chemotherapy. This supports a cDmax constraint of 3 EQD2 to limit ≥G3 toxicity to under 5%, consistent with the American Radium Society constraints (3 EQD2). ConCT with re-irradiation has a large radiosensitising effect. Limitations of this study include the use of old, retrospective data resulting in wide CIs around the predictions and insufficient data to predict a volumetric constraint. Further modelling with more detailed dose data is required to refine and validate these predictions
Heart rate variability in cardiovascular disease diagnosis, prognosis and management
Get PDFHeart rate variability (HRV), the variation in intervals between consecutive heartbeats, reflects autonomic nervous system function and has been studied as a potential biomarker in cardiovascular disease (CVD). While reduced HRV has been linked to arrhythmias, heart failure, and ischaemic heart disease, findings across studies are mixed and its prognostic value remains debated. This review evaluates HRV's diagnostic, prognostic, and therapeutic roles in CVD. HRV can reveal autonomic dysfunction early, predict outcomes such as sudden cardiac death and recurrent myocardial infarction, and track recovery after cardiac events. It also shows promise in monitoring comorbid conditions like heart failure and depression that exacerbate cardiovascular risk. Advancements in wearable technology and machine learning are expanding HRV's potential. Wearable devices enable continuous, non-invasive HRV monitoring, while machine learning algorithms enhance the precision and predictive power of HRV analysis. These innovations may facilitate real-time data collection and tailored treatment plans, though their clinical utility requires validation in larger, prospective trials. Key challenges remain, including measurement variability, lack of standardisation, and limited incremental prognostic value over established risk factors. This review highlights HRV's emerging role in personalised cardiovascular care while acknowledging the substantial research needed before widespread clinical adoption
Accelerating Meteorological and Ecological Drought in Arid Coastal–Mountain System: A 72-Year Spatio-Temporal Analysis of Mount Elba Reserve Using Standardized Precipitation Evapotranspiration Index
Get PDFDryland coastal–mountain systems stand at the frontline of climate change, where steep topographic gradients amplify the balance between resilience and collapse. Mount Elba—Egypt’s hyper-arid coastal–mountain reserve—embodies this fragile equilibrium, preserving a seventy-year climatic record across a landscape poised between sea and desert. Here, we present the first multi-decadal, spatio-temporal assessment (1950–2021) integrating the Standardized Precipitation–Evapotranspiration Index (SPEI-6) with satellite-derived vegetation responses (NDVI) along a ten-grid coastal–highland transect. Results reveal a pervasive drying trajectory of −0.42 SPEI units per decade, with vegetation–climate coherence (r ≈ 0.3, p < 0.05) intensifying inland, where orographic uplift magnifies hydroclimatic stress. The southern highlands emerge as an “internal drought belt,” while maritime humidity grants the coast partial refuge. These trends are not mere numerical abstractions; they trace the slow desiccation of ecosystems that once anchored biodiversity and pastoral livelihoods. A post-1990 regime shift marks the breakdown of wet-season recovery and the rise in persistent droughts, modulated by ENSO teleconnections—the first quantitative attribution of Pacific climate signals to Egypt’s coastal mountains. By coupling climatic diagnostics with ecological response, this study reframes drought as a living ecological process rather than a statistical anomaly, positioning Mount Elba as a sentinel landscape for resilience and adaptation in northeast Africa’s rapidly warming drylands
Jihād and the Protection of Places of Worship in Early Islam: Between Covenant, Conquest, and a Just Peace †
Get PDFThis article examines the relationship between jihād and the protection of non-Muslim places of worship in early Islam. Drawing primarily on Qurʾānic verses 22:39–41 and the Covenants of the Prophet, it employs a synchronically comparative framework that analyzes a broad corpus of textual sources, seeking to reconstruct how the early Muslim worldview understood the justification for jihād. It also examines the norms governing conduct after conflict, particularly in relation to treaty-making. The article attempts to make sense of Q22:39–41 within the broader landscape of late antiquity, which was marked by religious persecution and the destruction of sanctuaries under Byzantine and Sasanian rule. The study highlights how clear rules of engagement were articulated in early Islam, including limits on violence and the consequences of treaty violation. It argues that the motivations behind the early conquests cannot be reduced to material interests but rather were guided by a theological and ideological vision linking conquest with the establishment of a just peace, one grounded in the protection of communities, faith, and places of worship through a covenantal paradigm