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Impact of Antithrombotic Therapy on Thrombotic and Bleeding Complications after Elective Endovascular Repair of Abdominal Aortic Aneurysms
Get PDFPurpose: To investigate the influence of antithrombotic therapy on occurrence of thrombotic and bleeding complications after endovascular aneurysm repair (EVAR). Methods: In this retrospective single-center cohort study, patients who underwent elective endovascular aneurysm repair for abdominal aortic aneurysm were categorized into three antithrombotic groups: single antiplatelet therapy (SAPT), anticoagulants, or dual antiplatelet therapy (DAPT). Outcome measures were the incidence of major adverse cardiovascular events (MACE), prosthetic limb occlusions, and bleeding complications during follow-up. Results: Among 616 patients (SAPT: n = 450, anticoagulants: n = 84, and DAPT: n = 82), Kaplan–Meier analysis showed no significant difference (log-rank p = 0.37) in incidence of MACE between patients receiving SAPT (20.9%), anticoagulants (25.0%), and DAPT (14.6%) during a median follow-up of almost 4 years. In multivariable Cox regression analysis, only age (HR = 1.03; 95% CI 1.01–1.06, p = 0.01) and American Society of Anesthesiologists (ASA) classification (HR = 1.46; 95% CI 1.12–1.91; p = 0.01) were significant predictors for MACE. Prosthetic limb occlusion was observed in 38 patients during a median follow-up of 4 years; incidence between patients receiving SAPT (5.8%), anticoagulants (10.7%), and DAPT (3.7%) was not significantly different (log-rank p = 0.08). Age (HR = 0.96; 95% CI 0.92–1.00; p = 0.03) and use of anticoagulants (HR = 3.79, 95% CI 1.46–9.83; p < 0.01) were significant predictors for prosthetic limb occlusion. Bleeding complications occurred in 73 patients during median follow-up of almost 4 years, without significant difference (log rank p = 0.06) in incidence between patients receiving SAPT (10.7%), anticoagulants (19.0%), and DAPT (11.0%). ASA classification (HR = 1.74; 95% CI 1.23–2.46; p < 0.01) was a significant predictor for bleeding complications. Conclusion: Use of anticoagulants after EVAR appears to be associated with a higher risk of prosthetic limb occlusion compared to the use of single or dual antiplatelet therapy.</p
Structured porous silicon gas diffusion layers for electrochemical CO2 reduction
Get PDFThis thesis focuses on fabricating structurally well-defined gas diffusion layers (GDLs) and exploring their role in electrochemical CO2 reduction. It also establishes strategies for characterizing and operating CO2 electrolyzers using these structured gas diffusion electrodes (GDEs) while investigating the relationship between their morphology and transport properties. The fabricated porous Si membranes serve as model GDLs to study how pore size and porosity affect performance.The main result of the research is presented in the following four chapters.• Chapter 02 deals with the micro-fabrication procedure for fabricating structurally well-defined GDLs in the cleanroom. The fabrication process is outlined in three phases. Phase 01 defines the process flow for fabricating porous silicon and highlights the challenges encountered during the micro-fabrication process. Phases 02 and 03 describe the solutions to the problems identified during Phase 01 to fabricate porous Si successfully. At the end of this chapter, the challenges with the direct functionalization of Ag CL on the porous Si membrane and the issues with CO2 utilization are discussed.• Chapter 03 is divided into two parts. The first part investigates the challenges of CO2 utilization identified in Chapter 01 by using pressure control and optical imaging of the gas-liquid interface. The end of the first part discusses the stability of the established interface and the challenges in performing electrolysis and gas analysis. In part 02, the difficulties with forming and maintaining the gas-liquid interface were eliminated by moving to a zero-gap electrolyzer using the porous Si membrane. Further, the effect of porosity on CO2 electrolysis is presented with a discussion of the limitations caused by the mechanical stability of porous Si and the need for developing a stable and robust porous Si.• Chapter 04 concludes the study on the morphological properties of GDEs with structured porous Si. This chapter uses robust porous Si to present the effect of porosity and how it compares to the porosity of commercial carbon GDL substrates. Then, the electrochemical performance of porous Si with two different pore sizes at different current densities is compared, and a hypothesis on water and gas transport is presented.• Chapter 05 turns to conventional GDEs on the cathodic side in a zero-gap configuration and focuses on the stability of the CO2 electrolyzer influenced by the choice of the catalyst material on the anodic side. The baseline failure mechanisms were established with the widely used stable but expensive and rare Ir anode. Then, the cheaper and more abundant metallic Ni, a common anode material used in alkaline water electrolysis, was presented as an alternative, along with the failure mode and the studies undertaken to stabilize Ni.<br/
Inter-organizational pooling of NICU nurses in the Dutch neonatal network:A simulation-optimization study
Get PDFNeonatology care, the care for premature and severely ill babies, is increasingly confronted with capacity challenges. The entire perinatal care chain, including the Neonatal Intensive Care Unit (NICU), operates at high occupation levels. This results in refusals, leading to undesirable transports to other centers or even abroad, which affects quality of care, length of stay, and safety of these babies, and places a heavy burden on patients, their families, and involved caregivers. In this work we assess the improvement potential of network collaboration strategies that focus on reducing the number of patient transports, by allowing flexible deployment of nurses over the existing NICUs to match short-term changes in patient demand. We develop a discrete event simulation with an integrated optimization module for shift allocation and transfer optimization. A case study for the Dutch national NICU network, involving 9 NICU locations and current transport of 15% of all NICU patients in case of no flexible deployment, shows the potential of transporting staff instead of patients: About 70% of patient transports can be eliminated in case of 15-50% capacity sharing, and about 35% of nationwide transports is eliminated with up to 15% capacity sharing in the Dutch’s main conurbation area only.</p
Work alienation through the dialectical lens
Get PDFWork alienation (WA) is on the rise, especially in today's era of globalization and digitalization. However, its foundational ties to Marx and Hegel's conceptualizations are often overlooked. Despite extensive scholarly examination across disciplines, the conceptualization of WA remains plagued by a lack of consensus concerning its definitions, processes, and operationalizations. This systematic literature review identifies four major definitional approaches and their inherent limitations. First, equating WA with its antecedents diverts attention from its core mechanisms. Second, definition-by-negation leads to an underspecified construct, raising questions about empirical congruence. Third, defining WA through its correlates risks confusing it with different concepts. Fourth, expanding the construct of WA, to include distant constructs with surplus meanings, camouflages WA's essence, hindering a deeper understanding of the phenomenon. To enhance conceptual clarity, this paper aims to clarify WA's definitions, measurements, guiding theories, triggers, ramifications, and coping strategies within organizational contexts. Drawing from Hegel and Marx's dialectical lens, we compose a definition centered on a three-faceted self-other dialectic. Also, we present a three-stage developmental model, illustrating how WA develops and manifests itself as the relationships among the self, others, and work-life contexts evolve. By integrating elements from various management theories, we offer a fresh perspective for new research aimed at preventing WA. By addressing the theoretical and practical challenges that may arise, we emphasize the crucial role of Human Resource Management and team leaders in recognizing and mitigating WA to preserve vital individual, team, organizational and societal resources.</p
Signal-quality-aware multisensor fusion for atrial fibrillation detection
Get PDFThis letter introduces a novel method to enhance atrial fibrillation detection accuracy in healthcare monitoring. Wearable devices often face inconsistent signal quality due to noise. To address this, a multimodal data fusion technique that improves signal reliability during continuous monitoring is proposed. The method improves the precision of detecting R–R intervals by integrating wavelet coefficients from electrocardiogram, photoplethysmogram, and arterial blood pressure signals, weighted according to the quality of each signal. Furthermore, a bi-directional long short-term memory network is developed to accurately detect AF based on the derived heartrate or R–R intervals. Unlike prior studies, this work uniquely evaluates the system’s performance under noisy conditions, demonstrating significant accuracy improvements over single-channel methods. The system’s generalizability is confirmed by evaluating the classifier’s performance as the number of sensor inputs increases. At a signal-to-noise ratio of −10 dB, the accuracy improves by 4.51% with two sensor inputs and by 10.92% with three inputs, compared to using a single input
Pan‐European landslide risk assessment:From theory to practice
Get PDFAssessing landslide risk is a fundamental requirement to plan suitable prevention actions. To date, most risk studies focus on individual slopes or catchments. Whereas regional, national or continental scale assessments are hardly available because of methodological and/or data limitations. In this contribution, we present an overview of all requirements and limitations in landslide risk studies across all spatial scales, by means of a hybrid form that combines elements of original research with the comprehensive characteristics of a review study. The review critically analyses each component in the landslide risk analysis providing a detailed explanation of their state-of-the-art, with dedicated sections on susceptibility, hazard, exposure, and vulnerability. To put the theoretical framework to test, we also dive into a case study, expressed at the continental scale. Specifically, we take the main European mountain ranges and provide the reader with a textbook example of risk assessment for such a large territory. In doing so, we take into account issues associated with cross-national differences in landslide mapping. As a result, we identify landslide-prone European landscape and explore the associated possible economic consequences (human settlements and agricultural areas). We also analyze the population at risk during daytime and nighttime. Moreover, a modern view of the problem is explored in the form of how risk outcomes should be delivered to master planners and geoscientific personnel alike. Specifically, we convert our output into an interactive Web Application (https://pan-european-landslide-risk.github.io/) to include notions of scientific communication both to a large public as well as to a technical audience
Unlocking cellular secrets:Innovations driving research in liver disease & cancer
Get PDFLiver diseases, particularly chronic liver conditions such as metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic-associated steatohepatitis (MASH), as well as liver fibrosis and liver cirrhosis present serious global health challenges, causing millions of deaths. These diseases often progress silently, making early detection difficult and limiting treatment options. Additionally, liver cancer and prostate cancer are among the most common and deadly cancers in men due to late diagnosis and cancer metastasis. With the rising incidence of chronic liver diseases, lack of treatment options, and high mortality rates, there is an urgent need for:i. Improved understanding of disease mechanisms to identify novel therapeutic targets.ii. Discovery of biomarkers for early disease detection and identifying at-risk patients.iii. The development of safe and effective treatment strategies.Therefore, this thesis underscored the importance of unlocking cellular secrets in advancing disease understanding, developing early diagnostic tools, and exploring novel therapeutic strategies to tackle the growing burden of chronic liver diseases and cancer. This thesis contributed to this goal by:i. Enhancing MASLD disease understanding by developing a method for single cell secretion analysis of HSCs;ii. Adapting this method to evaluate macrophage subpopulations in MASH, identifying proinflammatory LAMS as potential therapeutic targets;iii. Exploring cellular differences between male and female immune cells in MASLD;iv. Advancing early diagnosis and prognosis of prostate cancer by identifying and isolating cCAFs as potential biomarkers for metastasis or treatment resistance;v. Developing the Mag-Click-Release system as a novel approach for isolating EVs as early liver cancer biomarkers;vi. Exploring the AXT-LPA pathway as a promising therapeutic target for the treatment of chronic liver diseases;vii. Establishing the novel ATX inhibitor Cpd17 as a promising therapeutic treatment for acute liver injury and pathological MASH in mice.The findings presented herein lay the groundwork for future research that integrates cellular biology, diagnostic innovations, and targeted therapies to improve patient outcomes in these complex conditions.<br/
Identifying falsified COVID-19 vaccines by analysing vaccine vial label and excipient profiles using MALDI-ToF mass spectrometry
Get PDFThe rapid development and worldwide distribution of COVID-19 vaccines is a remarkable achievement of biomedical research and logistical implementation. However, these developments are associated with the risk of a surge of substandard and falsified (SF) vaccines, as illustrated by the 184 incidents with SF and diverted COVID-19 vaccines which have been reported during the pandemic in 48 countries, with a paucity of methods for their detection in supply chains. In this context, matrix-assisted laser desorption ionisation-time of flight (MALDI-ToF) mass spectrometry (MS) is globally available for fast and accurate analysis of bacteria in patient samples, offering a potentially accessible solution to identify SF vaccines. We analysed the COVISHIELD™ COVID-19 vaccine; falsified versions of which were found in India, Myanmar and Uganda. We demonstrate for the first time that analysis of spectra from the vaccine vial label and its adhesive could be used as a novel approach to detect falsified vaccines. Vials tested by this approach could be retained in the supply chain since it is non-invasive. We also assessed whether MALDI-ToF MS could be used to distinguish the COVISHIELD™ vaccine from surrogates of falsified vaccines and the effect of temperature on vaccine stability. Both polysorbate 80 and L-histidine excipients of the genuine vaccine could be detected by the presence of a unique combination of MALDI-ToF MS peaks which allowed us to distinguish between the genuine vaccines and falsified vaccine surrogates. Furthermore, even if a falsified product contained polysorbate 80 at the same concentration as used in the genuine vaccine, the characteristic spectral profile of polysorbate 80 used in genuine products is a reliable internal marker for vaccine authenticity. Our findings demonstrate that MALDI-ToF MS analysis of extracts from vial labels and the vaccine excipients themselves can be used independently to detect falsified vaccines. This approach has the potential to be integrated into the national regulatory standards and WHO’s Prevent, Detect, and Respond strategy as a novel effective tool for detecting falsified vaccines.</p
Quantifying the relative contributions of rainfall and antecedent soil moisture to flood generation:Analysis of 963 Iranian catchments
Get PDFThroughout human history, floods have resulted in significant environmental and economic damages globally, and these impacts are expected to increase with climate change. Despite the occurrence of significant floods in Iran in recent decades, the precise impact of intense rainfall and antecedent soil moisture (ASM) on flood occurrence and how this relationship differs at different locations remains an area that requires further investigation. In this study, we analyzed annual maximum floods at 963 catchments across Iran from 1972 to 2019 (47 years). Moreover, we evaluated the relationship between catchment area and the main factor responsible for flood generation. Our analysis reveals a shift in the dominant factor driving flood generation from rainfall to ASM as the catchment area expands. The correlation between the topographic wetness index and the ratio of the relative significance of ASM (S) and daily rainfall (R) (i.e., Soil moisture-to-Rainfall Ratio; SRR=[Formula presented].), is positive, while the correlation between the magnitude of annual floods and SRR ratio is negative. A quantitative estimation of potential flood probability in ungauged catchments in Iran is facilitated by establishing a framework based on the relationship between easily measurable catchment attributes and the primary phenomenon of flood generation.</p