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A spatiotemporal marginalized zero-inflated Conway–Maxwell–Poisson regression model: application to international population outmigration within Asia
No full textData availability:
The data were obtained primarily from the United Nations Population Division (https://population.un.org), the World Bank (https://data.worldbank.org.cn/indicator), and the UCDP database (https://www.pcr.uu.se/research/ucdp). All datasets and codes in this study are available from the corresponding author upon reasonable request.Supplementary material:
Supplementary data are available online at: https://academic.oup.com/jrsssa/advance-article/doi/10.1093/jrsssa/qnag009/8462573?login=true&guestAccessKey=#supplementary-data .Asia is a principal source of global migration, and its intra-regional movements profoundly reshape the political, economic, and ecological landscapes of Asian nations. To address the spatiotemporal zero-inflated and dispersion present in migration data, as well as the need for interpretable inference on the overall mean, we develop a spatiotemporal marginalized zero-inflated Conway–Maxwell–Poisson (MZICMP) regression model. This model transcends the limitations of conventional zero-inflated approaches by employing a dispersion parameter that accommodates equidispersion, overdispersion, and under dispersion, and by jointly modelling excess zeros and the marginal mean through the inclusion of country-level covariates, smooth temporal effects, and spatial random effects. For parameter estimation, we implement a Bayesian Markov Chain Monte Carlo algorithm that combines Gibbs sampling with Metropolis–Hastings steps. Simulation demonstrates the model's efficacy in capturing both temporal autocorrelation and spatial zero-inflation patterns, and an empirical application to 1990–2020 intra-Asian out-migration reveals: (1) the share of secondary industry and the share of tertiary industry both show significant negative correlations with out-migration flows, whereas battle-related deaths and the total volume of bilateral trade exhibit positive correlations; (2) the average outmigration trend among Asian countries was relatively high during the period 2005–2010, then declined in 2015–2020; the model results indicate a satisfactory capture of this temporal pattern.The work was partially supported by the Graduate Research Innovation Project of Xinjiang Uygur Autonomous Region (XJ2025G219), the Beijing Natural Science Foundation (1242005), the Fundamental Research Funds for the Central Universities, and the Research Funds of Renmin University of China (No. 25XNN015), Ministry of Education Humanities and Social Sciences Research General Project (25YJA910005), and the High-Level Talent Special Program of Xinjiang University of Finance and Economics (2024XGC033, 2024XGC038)
A comprehensive life cycle assessment of vacuum insulation panels (VIPs) for applications at up to 70 °C
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Data will be made available on request.This paper presents a comprehensive Life Cycle Assessment (LCA) of Vacuum Insulation Panels (VIPs) with four core materials: fumed silica (FS) and three FS-based composites incorporating tree-based natural fibre (TNF) waste and tree-based natural ash (TNA), using a typical car painting booth (CPB) as a case study. A cradle-to-cradle evaluation is performed using two functional units: material transport capacity (6.2 tonnes per truck) and VIP dimensions (1 m × 1 m × 25 mm). VIPs were manufactured and their thermal conductivity measured over pressures of 0.64–1000 mbar and temperatures of 20–70 °C. Ageing effects were assessed by storing VIPs at 70 °C and 75% relative humidity for 12 months. Measured thermal conductivities were used to predict CPB energy consumption over a 10-year operational lifetime. Results show that FS–TNA VIPs (S4) reduced total cradle-to-cradle energy demand by 82,761 MJ compared with FS VIPs (S1) using Cut-off approach. However, this energy benefit did not translate into a climate advantage, as S4 exhibited a higher climate change impact of 893 kg CO2 eq, primarily due to pyrolysis-related emissions. Under the Allocation at Point of Substitution (APOS) approach, S4 reduced total energy demand by 17,216 MJ and climate change impact by 141 kg CO2 eq relative to FS, reflecting both operational energy savings and avoided biomass degradation emissions. When expressed per unit of energy saved relative to S1, S4 resulted in 55.0 kg CO2 eq per GJ under the modified Cut-off scenario used as the main modelling approach in this study, and (−) 8.2 kg CO2 eq per GJ under the modified APOS scenario used as an alternative allocation approach, highlighting the scenario-dependent energy–climate trade-off. Overall, the study demonstrates that trade-offs between embodied emissions, operational energy demand, and end-of-life modelling influence VIP environmental performance and provides a transparent methodology to support material selection for high-temperature industrial applications.Acknowledgment:
Singh and Sivan thankfully acknowledge India's SPARC 2019-2020 funding received for the project number 2066
Mechanical and in situ thermal-related behavior during directed energy deposition additive manufacturing of a high-performance Al alloy
Full text linkHighlight:
• We designed an Al alloy for DED-AM applications, and the as-build components achieve ultra-fine microstructure, low residual stress, and good mechanical properties.
• We established a novel multimodal characterization methodology that integrates in situ X-ray imaging, X-ray diffraction, and infrared imaging for material design purposes.
• We experimentally quantified in situ thermal behavior, such as temperature distribution, phase formation and stress accumulation during DED of our designed Al alloy.
• We revealed the mechanisms behind microstructural refinement under non-equilibrium condition, and provided mechanism-based guidance for alloy design tailed for AM.Data availability:
Data will be made available on request.Directed energy deposition (DED) additive manufacturing (AM) can fabricate, repair, and join near-net-shaped components for high-performance engineering applications, including biomedical, energy, and transport sectors. The broader adoption of DED remains constrained by the limited number of alloys available that can be reliably manufactured without imperfections, hence limiting mechanical properties. Here, we designed an Al–Ni–Ce–Mn–Fe AM alloy that can achieve an ultra-fine microstructure (<5 μm), uniform distribution of intermetallics, low residual stress (<32 MPa), and superior mechanical properties in as-built DED components. Compared to DED AlSi10Mg in the as-built state using the same conditions, the yield increased by 70%, and the ultimate tensile strength by 50%. DED-AM involves rapid cooling and complex thermal conditions, which largely influence the property of the final components. Post-characterization cannot capture the time resolved thermal behavior, hence offer limited mechanism-based guide for alloy design. In this study, we develop a novel multimodal characterization methodology for correlative in situ X-ray imaging, X-ray diffraction, and infrared imaging, enabling quantification of the in situ thermal-related behavior, including phase evolution, temperature distribution, and stress accumulation during DED. We elucidated key mechanisms driving the structure refinement and stress development in this alloy. The insights gained into the interplay between alloy composition, thermal-related behavior, and performance under specific AM conditions inform next-generation material design tailored for AM technologies.The authors acknowledge the support from the UKRI—EPSRC, Grants Numbered EP/W006774/1, EP/P006566/1, EP/W003333/1, and EP/V061798/1. PDL is funded by the support from a Royal Academy of Engineering Chair in Emerging Technologies (CiET1819/10); CLAL is funded in part by EP/W037483/1 and IPG Photonics/ Royal Academy of Engineering Senior Research Fellowship in SEARCH (Ref: RCSRF2324-18-71). The atomization of powder was done by a proprietary ultrasonic atomization technology developed and implemented by Amazemet Sp. z o.o. This research used resources of the Diamond Light Source (DLS) in Beamline I12 (MG-34549)
Maps and Diaspora: Affect, Agency and Epistolary Praxis
Full text linkData Availability Statement:
The data that support the findings of this study that include historical maps are available from the Royal Geographical Society—with the Institute of British Geographers. Restrictions may apply to the availability of these data, which may be under licence. Data are used by the authors with the permission of the Royal Geographical Society—with the Institute of British Geographers.This article also appears in: Map Room Conversations (https://rgs-ibg.onlinelibrary.wiley.com/doi/toc/10.1111/(ISSN)1475-4762.map-room-conv).Following discussions, interactions and reflections during the 2024 Royal Geographical Society (with IBG) conference ‘Map Room Conversations’ sessions, this paper examines archival maps in relation to diaspora through an affective lens. Using an auto-ethnographic epistolary praxis of letter-writing and the therapeutic prompt ‘What came up for you?’, it aims to bring out marginalised narratives and enable diasporic subjects to reclaim agency over their histories and identities. As a medium for the performativity of memory, letter-writing enables affective engagement with maps of ‘Hindustan’ and ‘Himalaya’, facilitating access to suppressed emotions and genealogical narratives, shifting away from viewing maps as merely colonial artefacts and repositioning them as ‘mediators’ of diasporic affect and agency, thus animating them as sites of remembering, reconnecting and healing.This work was supported by the British Academy, SHAPE Involve and Engage
Generation and stability of bulk nanobubbles in liquid fuel and their influence on spray characteristics
Full text linkHighlights:
• Stable air nanobubbles in gasoline produced via hydrodynamic cavitation.
• Initial concentration of nanobubble/mL with 35 nm mean size was achieved.
• Air nanobubbles remained stable in gasoline for over 120 days.
• Nanobubbles reduced spray penetration and enhanced atomization.
• ANB fuel showed lower droplet velocity and a uniform size distribution.Data availability:
Data will be made available on request.Nanobubbles have attracted increasing attention due to their unique physicochemical properties; however, their application in fuel and combustion research remains limited. This study investigates the generation of air nanobubbles (ANBs) in gasoline and their influence on spray characteristics in gasoline direct injection (GDI) systems. ANBs were produced using a custom-designed hydrodynamic cavitation generator incorporating a zero-clearance pump. Dynamic light scattering and nanoparticle tracking analysis demonstrated the formation of a highly concentrated nanobubble population (5.12 × 10¹¹ particles/mL), with diameters ranging from 40 to 200 nm and a negative zeta potential between −20 and −25 mV, indicating good stability in gasoline. Spray behavior of ANB-enriched gasoline was evaluated in a constant-volume chamber using a single-hole GDI injector at injection pressures of 50, 100, and 150 bar. Diffused back illumination technique was employed to analyze macroscopic spray characteristics, while phase Doppler anemometry was used to measure droplet size and axial velocity distributions. Compared to baseline gasoline, ANB fuel exhibited consistently shorter penetration lengths, smoother spray boundaries, and lower spray density factors, suggesting improved atomization and air–fuel mixing. PDA measurements further revealed reduced axial droplet velocities, attributed to enhanced secondary breakup associated with nanobubble dynamics. These findings demonstrate that air nanobubbles can significantly influence spray development in GDI systems, offering a promising approach for improving fuel atomization and supporting the development of advanced, high-efficiency combustion technologies.This work was supported by a UKRI Future Leaders Fellowship (MR/ T042915/1, UKRI1057)
Design and Material Characterisation of Additively Manufactured Polymer Scaffolds for Medical Devices
Full text linkData Availability Statement:
The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.Additive manufacturing has been adopted in several industries including the medical field to develop new personalised medical implants including tissue engineering scaffolds. Custom patient-specific scaffolds can be additively manufactured to speed up the wound healing process. The aim of this study was to design, fabricate, and evaluate a range of materials and scaffold architectures for 3D-printed wound dressings intended for soft tissue applications, such as skin repair. Multiple biocompatible polymers, including polylactic acid (PLA), polyvinyl alcohol (PVA), butenediol vinyl alcohol copolymer (BVOH), and polycaprolactone (PCL), were fabricated using a material extrusion additive manufacturing technique. Eight scaffolds, five with circular designs (knee meniscus angled (KMA), knee meniscus stacked (KMS), circle dense centre (CDC), circle dense edge (CDE), and circle no gradient (CNG)), and three square scaffolds (square dense centre (SDC), square dense edge (SDE), and square no gradient (SNG), with varying pore widths and gradient distributions) were designed using an open-source custom toolpath generator to enable precise control over scaffold architecture. An in vitro degradation study in phosphate-buffered saline demonstrated that PLA exhibited the greatest material stability, indicating minimal degradation under the tested conditions. In comparison, PVA showed improved performance relative to BVOH, as it was capable of absorbing a greater volume of exudate fluid and remained structurally intact for a longer duration, requiring up to 60 min to fully dissolve. Tensile testing of PLA scaffolds further revealed that designs with increased porosity towards the centre exhibited superior mechanical performance. The strongest scaffold design exhibited a Young’s modulus of 1060.67 ± 16.22 MPa and withstood a maximum tensile stress of 21.89 ± 0.81 MPa before fracture, while maintaining a porosity of approximately 52.37%. This demonstrates a favourable balance between mechanical strength and porosity that mimics key properties of engineered tissues such as the meniscus. Overall, these findings highlight the potential of 3D-printed, patient-specific scaffolds to enhance the effectiveness and customisation of tissue engineering treatments, such as meniscus repair, offering a promising approach for next-generation regenerative applications.The Royal Society Research Grant (RG\R1\241133); EPSRC Centres for Doctoral Training Grant (EP/S023763/1)
State-Dependent CNN–GRU Reinforcement Framework for Robust EEG-Based Sleep Stage Classification
Full text linkData Availability Statement:
The data that support the findings of this study are not openly available due to reasons of sensitivity and are available from the corresponding author upon reasonable request.Recent advances in automated learning techniques have enhanced the analysis of biomedical signals for detecting sleep stages and related health abnormalities. However, many existing models face challenges with imbalanced datasets and the dynamic nature of evolving sleep states. In this study, we present a robust algorithm for classifying sleep states using electroencephalogram (EEG) data collected from 33 healthy participants. We extracted dynamic, brain-inspired features, such as microstates and Lempel–Ziv complexity, which replicate intrinsic neural processing patterns and reflect temporal changes in brain activity during sleep. An optimal feature set was identified based on significant spectral ranges and classification performance. The classifier was developed using a convolutional neural network (CNN) combined with gated recurrent units (GRUs) within a reinforcement learning framework, which models adaptive decision-making processes similar to those in biological neural systems. Our proposed biomimetic framework illustrates that a multivariate feature set provides strong discriminative power for sleep state classification. Benchmark comparisons with established approaches revealed a classification accuracy of 98% using the optimized feature set, with the framework utilizing fewer EEG channels and reducing processing time, underscoring its potential for real-time deployment. These findings indicate that applying biomimetic principles in feature extraction and model design can improve automated sleep monitoring and facilitate the development of novel therapeutic and diagnostic tools for sleep-related disorders.This research is supported by a research grant from the University of Tabriz, number s/2843
Measurements of the inclusive W and Z boson production cross sections and their ratios in proton-proton collisions at √s = 13.6 TeV
Full text linkA version of the article is available at arXiv:2503.09742v2 [hep-ex] (https://arxiv.org/abs/2503.09742v2). Comments: Replaced with the published version. Added the journal reference and the DOI. All figures and tables can be found at https://cms-results.web.cern.ch/cms-results/public-results/publications/SMP-22-017 (CMS Public Pages). Report number: CMS-SMP-22-017, CERN-EP-2025-013. Submission history: From: The CMS Collaboration: [v1] Wed, 12 Mar 2025 18:41:54 UTC (488 KB); [v2] Wed, 14 Jan 2026 16:18:49 UTC (487 KB).Measurements are presented of the W and Z boson production cross sections in proton-proton collisions at a center-of-mass energy of 13.6 TeV. Data collected in 2022 and corresponding to an integrated luminosity of 5.01 fb⁻¹ with one or two identified muons in the final state are analyzed. The results for the products of total inclusive cross sections and branching fractions for muonic decays of W and Z bosons are 11.93 ± 0.08 (syst) ± 0.17 (lumi) {-0.07}{+0.07} (acceptance) nb for W⁺ boson production, 8.86 ± 0.06 (syst) ± 0.12 (lumi) {-0.06}{+0.05} (acceptance) nb for W⁻ boson production, and 2.021 ± 0.009 (syst) ± 0.028 (lumi) {-0.013}{+0.011} (acceptance) nb for the Z boson production in the dimuon mass range of 60–120 GeV, all with negligible statistical uncertainties. Furthermore, the corresponding fiducial cross sections, as well as cross section ratios for both fiducial and total phase space, are provided. The ratios include charge-separated results for W boson production (W⁺ and W⁻) and the sum of the two contributions (W±), each relative to the measured Z boson production cross section. Additionally, the ratio of the measured cross sections for W⁺ and W⁻ boson production is reported. All measurements are in agreement with theoretical predictions, calculated at next-to-next-to-leading order accuracy in quantum chromodynamics.SCOAP3
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