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Access status: Open Access ,
Deferred Cord Clamping in Very Preterm Triplets and Outcomes: A Retrospective Cohort Study
(Karger Publishers, 2025-12-18) Shah, Prakesh S.; Su, Yi-Chen; El-Naggar, Walid; Hobson, Sebastian R.; Ronzoni, Stefania; Beltempo, Marc
Introduction: There is a paucity of data with regards to benefits and harms associated with deferred cord clamping (DCC) in triplets. The objective was to compare outcomes of triplets following exposure to DCC in a national cohort admitted to the NICU in Canada with a gestational age of <33 weeks. Methods: We conducted a retrospective, population-representative, cohort study of triplets born before 33 weeks of gestation in a Canadian NICU. DCC was defined as cord clamping conducted after 30 s of the birth of the neonate. Our primary outcome was survival without neurological injury or late-onset sepsis, and individual outcomes of neonatal survival, severe neurological injury, and late-onset sepsis. We utilized the target trial emulation technique to analyze data considering discordant exposure, discordant outcomes, and the correlated nature of outcomes within the triplet set. Results: Of the 226 sets of triplets included in the study, 100 sets had all 3 received DCC, 22 had 2/3 received DCC, 32 had 1/3 received DCC, and 72 had none received DCC for a total of 376 neonates who received DCC and 302 did not receive DCC. There was no association of benefit or harm between DCC and any of the outcomes studied in any of the analyses. Univariate comparison of outcomes indicated higher receipt of inotropes and higher length of stay among those who did not receive DCC compared to other groups. Conclusion: In this retrospective cohort study, DCC was not associated with benefit or harm in very preterm triplets.
Access status: Open Access ,
Consolidation Behavior of Geotextile-Assisted Vacuum Preloading for Dredged Soil
(Canadian Science Publishing, 2026-02-21) He, Zili; Dai, Bochen; Liu, Sijie; Sun, Hong-lei; Xu, Shanlin; Zhang, Hao
Vacuum preloading combined with horizontal drains has been increasingly applied to improve dredged soils. This study proposes a novel vacuum preloading method in which geotextiles are used directly as horizontal drains. Four model tests were conducted to evaluate the feasibility and consolidation mechanism in comparison with prefabricated horizontal drain (PHD) vacuum preloading. The results show that vacuum pressure was rapidly transmitted along the geotextile, reaching 87.6–94.9% of the applied vacuum pressure at the geotextile surface in the initial stage and remaining at approximately 92% at later stages. The degree of consolidation reached about 90%, exceeding that obtained using a single PHD. Non-uniform consolidation was observed, with a vacuum loss of approximately 20 kPa at 20 cm from the geotextile. After treatment, the water content and vane shear strength near the geotextile reached approximately 44% and 45 kPa, respectively. Particle image velocimetry (PIV) revealed predominantly vertical compression with negligible horizontal strain, indicating that the consolidation can be reasonably approximated as one-dimensional. Scanning electron microscopy (SEM) showed reduced fine-particle intrusion into the geotextile due to its lower unit-area water flux. A double-layer consolidation model was introduced to predict the consolidation degree, and showed good agreement with the experimental measurements.
Access status: Open Access ,
Spatial Variability of Kinematic Pile Response in Liquefiable Slopes: Effects of Static Shear Bias and Partial Drainage
(Canadian Science Publishing, 2026-02-02) Sahare, Anurag; Ueda, Kyohei
Liquefaction-induced lateral spreading in sloping, layered ground can impose highly non-uniform kinematic demands on adjacent piles, yet most design checks assume uniform soil pressures. We present dynamic centrifuge tests on a three-layer deposit (dense crust over loose sand, underlain by a dense crust) at slopes of 5° and 10° with piles at upslope, midslope, and downslope positions, and introduce three indicators, the static-to-cyclic bias ratio (Ψ), the stress-reversal fraction (SRF), and an effective Deborah number (Deeff) to time drainage feasibility. During shaking, response is largely undrained (Deeff > 1), with a greater tendency for stress non-reversal at the steeper slope; partial drainage becomes effective mainly post-shaking, first near the surface, with vertical extent governed by drainage-path length and loose-layer permeability. Spatial heterogeneity in excess pore pressure and stiffness yields inter-pile differences: downslope piles mobilize the largest co-seismic moments; and after shaking pile-head segments re-stiffen quickly while deeper segments retain 0.6-0.9 Mpeak over the 0-250 s post-shaking window. JRA-based envelopes reproduce overall shape at 5° but, under stronger static bias (10°), systematically underpredict mid-column curvature near the loose-crust interface and overpredict base demand; free-field Rankine bounds confirm the plausibility of measured magnitudes. The results establish a mechanism-driven framework to identify where and when curvature concentrates, to interpret the role of post-shaking drainage, and inform the use of code-based envelopes.
Access status: Open Access ,
A Dual-Level Particle Breakage Model for Irregular Particles in DEM
(Canadian Science Publishing, 2026-02-05) Xu, Chengkai; Wang, Pei; Yin, Zhen-Yu; GAO, Xiang; Xu, Changjie
Particle breakage plays a crucial role in the mechanical behaviour of granular soils. However, existing breakage models in discrete element method (DEM) struggle to accurately represent the breakage process of irregular particles with high computational efficiency. This study proposes a dual-level particle breakage model for irregular particles. At the particle level, the octahedral shear stress serves as the failure criterion, determining whether the particle undergoes breakage. Once the particle level breakage condition is met, sub-particle level failure criteria are applied to identify critical contact points leading to local breakage. The proposed model is validated through comparisons with experimental results including single particle crushing tests and oedometer tests with irregular-shaped particles. In the single particle crushing test simulations, the model successfully reproduces fracture patterns, fragment size distributions, and sequential particle breakage observed in the experiments. When modelling the multi-particle oedometer tests, the model accurately captures the stress-strain response, particle size distribution evolution, and fragment morphologies under a wide range of stress levels. Overall, the proposed method offers a robust and efficient framework for simulating the breakage of irregular-shaped particles, with strong potential for addressing engineering challenges related to particle breakage.
Access status: Open Access ,
Making Institutional Structure Visible: A Measurement Approach to Internal Alignment in Publicly Accountable Systems
(2026) Huang, Jim Y.
Publicly accountable systems generate extensive data on funding, participation, and performance. In education policy, these data are commonly organized into indicators that support reporting, comparison, and oversight. Yet the presence of observable indicators does not in itself establish a measurement grammar for calibration. While existing frameworks provide structured visibility, they do not necessarily specify how internal structural alignment within the system is to be rendered observable. This paper addresses this gap by developing a structural measurement framework for reading publicly accountable data surfaces. The framework does not introduce new data or external benchmarks. Instead, it operates on realized, publicly reported records and applies dual mappings to the same empirical surface. By distinguishing arithmetic aggregation from geometric configuration, it renders internal structural alignment—and divergence—observable as a property of the system itself. The empirical illustration is drawn from the Ontario education funding system. Over the past decade, this system has undergone a series of policy developments, including the expansion and subsequent restriction of public-private partnership arrangements, the centralization of governance authority through legislative reform, and shifts in student financial assistance and tuition structures. Rather than treating these developments as discrete interventions or evaluating their outcomes against predefined targets, this paper reconstructs them as a sequence of rule-triggered reclassification events across entry, control, and burden positions within a publicly accountable system of resource allocation. Within this configuration, a distinction is maintained between public capital (state-collected funds) and private capital (post-tax resources held by households). Policy actions are read as mechanisms through which these forms of capital are repositioned across institutional boundaries and along intergenerational pathways. This perspective shifts the analytical focus from outcome evaluation to structural positioning, emphasizing how admissible pathways, governance authority, and cost-bearing arrangements are reassigned over time. Existing approaches in education policy and public administration provide extensive tools for evaluation, explanation, and accountability. These approaches are effective in organizing data for reporting and comparative analysis. However, they do not exhaust the problem of measurement. In particular, they do not specify how to observe internal alignment within a system when no stable reference structure or benchmark is presupposed. Under such conditions, system movements may be recorded and narrated, but not calibrated. This paper therefore isolates a distinct measurement problem: how to render internal structural alignment visible on a single publicly accountable data surface. It proposes a complementary framework based on dual readouts of the same dataset. The arithmetic index (ITI) captures aggregated distribution, while the geometric configuration (gITI) preserves relational structure across units. The divergence between these mappings (IDI-R) is treated as a structural property generated within the system, rather than as a deviation from an external benchmark. The contribution is supplementary rather than substitutive. The framework developed here does not replace existing indicator-based or evaluative approaches. It specifies an additional measurement layer concerned with structural alignment and offers a method for making that layer observable. By doing so, it provides a way of reading publicly accountable systems in which adjustment is observable, but calibration remains under-specified.