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Predicting haemodialysis arteriovenous fistula outcomes using computational fluid dynamics and ferumoxytol-enhanced MRI
Full text linkObjective:
Arteriovenous fistulas (AVF) are the preferred vascular access for maintenance haemodialysis. However, AVF non-maturation occurs in up to 60% of patients, frequently caused by inadequate vascular remodelling or stenosis development. This study explores the relationships between AVF anatomy, haemodynamics and AVF outcomes by combining, uniquely, high-fidelity numerical simulations and state-of-the-art ferumoxytol-enhanced magnetic resonance imaging (Fe-MRI) in patients.
Methods:
Patients underwent Fe-MRI 6 weeks after AVF creation. A novel computational fluid dynamics (CFD) methodology was employed to rigorously investigate haemodynamic metrics, including wall shear stress (WSS) and oscillatory shear index (OSI), and quantify changes in the AVF lumen at 1 cm intervals along the proximal artery, anastomosis and AVF vein. The primary outcome was AVF success, defined as AVF usage (assisted or unassisted) for dialysis for at least 3 months. ROC analysis was conducted to assess anatomical predictors of AVF flows of ⩾1000 ml/min.
Results:
The analysis included 17 AVFs (13 successful, 4 failed). Compared to failed fistulas, successful AVFs had higher mean WSS and OSI. Failed AVFs exhibited different haemodynamics, including lower flow rates with less helical flow. On ROC analysis, the three metrics associated with the highest area under the curve (AUC) values were the feeding artery curvature (0.82) and diameter (0.76), and draining vein diameter (0.74), with a combined AUC value of 0.83.
Conclusion:
These data suggest that high WSS, OSI, larger feeding artery and draining vein diameters and lower feeding artery curvature are associated with successful AVF outcomes. Whilst venous parameters are important, this study highlights the critical role of feeding artery characteristics, particularly diameter and curvature. These findings provide significant insights into the role of haemodynamics and geometry in modulating AVF maturation, suggesting that incorporation of arterial metrics into preoperative assessments could enhance surgical decision-making for more reliable AVF maturation and better long-term outcomes in haemodialysis patients
Distributed consensus network: a modularized communication framework and reliability probabilistic analysis
No full textIn this paper, we propose a modularized framework for communication processes applicable to crash and Byzantine fault-tolerant consensus protocols. We abstract basic communication components and show that the communication process of the classic consensus protocols such as RAFT, single-decree Paxos, PBFT, and Hotstuff, can be represented by the combination of communication components. Based on the proposed framework, we develop an approach to analyze the consensus reliability of different protocols, where link loss and node failure are measured as a probability. We propose two latency optimization methods and implement a RAFT system to verify our theoretical analysis and the effectiveness of the proposed latency optimization methods. We also discuss decreasing consensus failure rate by adjusting protocol designs. This paper provides theoretical guidance for the design of future consensus systems with a low consensus failure rate and latency under the possible communication loss
Living with a hereditary cancer syndrome: personal perspectives and implications for oncology nurses
No full textObjectives:
To explore the lived experiences of individuals with hereditary cancer syndromes and identify implications for oncology nursing practice.
Methods:
We invited individuals with hereditary cancer syndromes to contribute first-person narratives describing their experiences. Narratives were thematically analyzed and triangulated with existing literature on patient experiences and the role of oncology nurses in hereditary cancer syndrome care.
Results:
Across the narratives, co-authors described the psychological burden of living with uncertainty, marked by anticipatory anxiety surrounding surveillance, symptoms, and potential diagnoses. The analysis allowed us to identify key themes defining the experience of living with hereditary cancer syndromes: psychological and emotional impact, difficulties in communication of genetic risk information, navigating the health care system, patient empowerment and self-management, and the role of nurses.
Conclusions:
Findings from this article highlight the lived experiences of individuals with hereditary cancer syndromes, consistent with existing evidence, showing persistent unmet needs that are not adequately addressed within the current health care system.
Implications for Nursing Practice:
The narratives highlight several areas where nurses play a critical role in supporting individuals with hereditary cancer syndromes, underscoring the need for comprehensive, personalized, and lifelong care in which nurses tailor interventions to individual syndromes, life stages, and coping styles
Strategy typology and non-GAAP earnings disclosure
No full textThis paper examines the influence of business strategy on firms’ discretionary disclosure of non-GAAP earnings. We find that innovation-oriented firms (i.e., prospectors) have a higher propensity of disclosing non-GAAP earnings, whereas efficiency-driven firms (i.e., defenders) are less likely to issue non-GAAP earnings. Subsequent tests reveal that the prospector managers are more likely to disclose non-GAAP earnings to ‘convert’ a GAAP loss into a non-GAAP profit and ‘meet and beat’ analyst forecasts, consistent with managers’ opportunistic use of non-GAAP earnings as a strategic device to engage in impression management. To corroborate the managerial opportunism behind non-GAAP earnings disclosure, we test the quality of non-GAAP exclusions and f ind that the managerial exclusions by prospectors are of lower quality. Cross-sectional analyses indicate that the positive relationship between business strategy and non-GAAP earnings disclosure is more pronounced amongst f irms with higher levels of prior accruals management, firms facing higher agency costs, and firms with higher managerial ability. Our results are robust to a battery of robustness tests such as triple-differences analysis based on exogenous shocks, propensity-score-matching technique, and instrumental variable approach. Overall, our study documents the role of business strategy as an intrinsic and non-financial firm characteristic in shaping the voluntary disclosure of financial information
Field measurements of environmental dose rate for trapped charge dating
No full textField measurements at or close to the sampling position used for dating are the most direct ways of estimating environmental dose rates. They usually happen in undisturbed settings under natural conditions, avoiding extensive post-processing or modelling. Over the last decades, the trapped charge dating community has proposed and actively applied multiple methods for field measurements. The most common approaches use active detectors, such as NaI or LaBr 3 produced dosimeters (ex.: CaF 2 crystals for gamma-ray spectrometry, or passive detectors based on artificially , Al 2 O 3 :C) to measure absorbed beta and/or gamma doses. Both active and passive methods have their advantages and disadvantages. Common to both techniques is that they are easy and cost- efficient to use once a laboratory has established a workflow. However, deciding on a specific system that best fits the typical requirements of a dating laboratory and establishing this system is often cost- and time- intensive. Here, we present and review commonly applied and established methods for estimating the environmental dose rate in the field. We focus on the required equipment, calibrations, and data processing tools to provide a primer. We conclude with a specific assessment of the cosmic dose rate, which is often strongly influenced by the topographical parameters of the research area
Xenon lamp weathering induced structural evolution and pyrolysis mechanisms of HDPE-ethanol processing residue composites
Full text linkThis study investigates how accelerated weathering influences the pyrolysis behavior of a bio-based composite prepared from high-density polyethylene (HDPE) and lignocellulosic ethanol-processing residue (EPR). The composites were subjected to xenon-lamp exposure for varying durations and subsequently analyzed using thermogravimetric analysis (TGA), TG-FTIR, Py-GC/MS and kinetic modelling. TGA results showed that weathering enhanced the crystallinity of the HDPE phase and reduced the maximum mass-loss rate, indicating inhibited volatilisation in the HDPE-dominated decomposition region. Iso-conversional kinetics further revealed a conversion-dependent response: the apparent activation energy decreased in the low-to-mid conversion region dominated by the residue fraction, whereas the activation energy associated with the HDPE-dominated region increased, consistent with crystallinity-enhanced resistance to polyethylene chain scission. The increased residual mass after aging is attributed not only to pre-loss/leaching of labile fractions during weathering but also to the formation of more stable residue structures (e.g., photo-induced crosslinking and lignin-derived condensed aromatic clusters) that persist during pyrolysis. TG-FTIR indicated a general decline in the intensity of functional-group absorption peaks, reflecting attenuated volatilization of both polymeric and lignocellulosic structures. Py-GC/MS demonstrated significant changes in product distribution: weathered samples generated higher yields of short-chain hydrocarbons such as propene, 1-pentene, and 1-decene, while oxygen-containing compounds (e.g., alcohols, esters, phenols) were reduced. These results clarify how controlled weathering alters the structural and chemical evolution of HDPE–EPR composites during pyrolysis. The findings provide new insights for optimizing thermochemical recycling and energy-recovery strategies for residue-derived or weathered bio-plastic composites
‘Transform the world’: the critique of everyday life, autogestion and the ‘withering away’ of the state in the sociology of Henri Lefebvre
No full textNo abstract available
Finerenone and quality of life assessed using the EuroQol 5-Dimension Questionnaire Level Sum Score in patients with HFmrEF or HFpEF
Full text linkNo abstract available
Long-term effects of multi-media education and 'foot alerts' through MyU app on diabetic foot care: a pilot RCT in moderate-high risk individuals
No full textBackground:
Diabetic foot ulceration (DFU) is the leading cause of nontraumatic amputations in people with diabetes. Research shows that improving patient awareness can result in short-term improvements, but Cochrane reviews report insufficient high-quality evidence.
Objective:
This study aims to investigate the effects of multimedia presentation and smartphone alerts to enhance long-term knowledge and foot care behaviors in individuals at moderate-to-high risk of DFU.
Methods:
Participants were randomized to a control group, receiving usual diabetic foot care advice (n=40), or an intervention group, receiving a multimedia diabetic foot care presentation and regular “foot alerts” through the MyU smartphone app on top of usual care (n=37). Patient’s knowledge and behaviors related to diabetic foot care were assessed at baseline and after 12 months. Repeated measures ANOVA was conducted in both intention-to-treat and per-protocol analyses to evaluate the intervention’s effectiveness.
Results:
The findings were consistent across intention-to-treat and per-protocol analyses. In the intervention group, the number of podiatry visits was positively correlated with improved foot care behavior (r=0.408; P=.02), while the control group showed a negative correlation (r=−0.402; P=.02). No significant correlations were observed with knowledge scores. Although no significant time×group interactions were seen, the main effects of time were found for both knowledge (η²=0.12; P=.004) and behavior scores (η²=0.31; P<.001). Post hoc analysis showed a decline in knowledge scores in the control group (Cohen d=−0.24; P=.007) and improvements in behavior scores in both groups (Cohen d: intervention=0.61, control=0.63; all P<.001).
Conclusions:
The MyU app−based multimedia intervention was associated with improved foot care behaviors over 12 months, indicating potential benefits as an adjunct to usual diabetic foot care. However, no significant changes in diabetic foot care knowledge were observed. These findings suggest that while the applied digital multimedia tool may support behavior change, further research is needed to enhance knowledge retention and clinical impact. The study revealed that multimedia education alone may not be effective for long-term improvement in foot self-care knowledge and behavior among individuals at moderate-high DFU risk, but the reinforcement of educational material during follow-up podiatry visits could be effective.
Trial Registration:
ClinicalTrials.gov NCT03934944; https://www.clinicaltrials.gov/study/NCT0393494
Four-manifolds, two-complexes and the quadratic bias invariant
No full textKreck and Schafer produced the first examples of stably diffeomorphic closed smooth 4-manifolds which are not homotopy equivalent. They were constructed by applying the doubling construction to 2-complexes over certain finite abelian groups of odd order. By extending their methods, we formulate a new homotopy invariant on the class of 4-manifolds arising as doubles of 2-complexes with finite fundamental group. As an application we show that, for any k>=2, there exist a family of k closed smooth 4-manifolds which are all stably diffeomorphic but are pairwise not homotopy equivalent
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