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Experimental generation of vector Mathieu-Gauss beams
No full textWe experimentally generate vector Mathieu-Gauss beams, a family of structured light beams that belong to the broader class of vector Helmholtz-Gauss beams. Preliminary results for the TM-type solution demonstrate excellent agreement with theoretical predictions. The inhomogeneous transverse polarization distribution is characterized using the Stokes parameters, while the optical concurrence confirms a high degree of purity. These findings contribute to the understanding and control of structured vector beams
Financing circularity strategies in critical raw materials supply chains:Toward a novel blended framework
No full textThe transition to a circular economy (CE) has gained significant attention as a strategy to enhance sustainability across resource-intensive industries. However, its application within critical raw materials (CRMs) supply chains — and its potential to mitigate upstream supply risks — remains insufficiently explored. A key gap concerns how CRMs-dependent businesses can access the financial resources required to implement circularity strategies effectively. This study addresses that gap by synthesizing existing literature and proposing a Novel Blended Framework comprising two complementary components. First, we introduce a Circular Strategy–Risk Diagnostic Cube that enables firms to map specific categories of supply disruption to context-appropriate circularity strategies. Second, we develop an Integrated Financing Architecture that identifies how public, private, and hybrid financing instruments can be combined to support these strategies, given the diverse risk profiles and capital needs of CE initiatives. Drawing on the perspectives of three key stakeholder groups — CRMs-dependent businesses, private financial entities, and the public sector — we identify critical funding challenges, outline actionable pathways to improve access to finance and capital, and formulate a research agenda to strengthen the financial underpinnings of circular transitions. Our findings offer both theoretical advancements and practical recommendations, emphasizing the need for collective action across sectors to achieve sustainable and financially viable CRMs supply chains
Concomitant IgA nephropathy and dermatomyositis:A case-based review
No full textIgA nephropathy concomitant with dermatomyositis is extremely rare. We describe a 38-year-old male who presented with generalized swelling and scanty red urine followed by proximal muscle weakness and dysphagia. Urinalysis revealed proteinuria, hematuria, and red blood cell casts. Renal biopsy showed IgA deposition in the mesangial tissue of the glomerulus by immunofluorescence technique, compatible with IgA nephropathy. He had no preceding history of respiratory tract infections or associated illnesses like inflammatory bowel disease, ankylosing spondylitis, psoriasis, cirrhosis or IgA vasculitis. The patient was treated with prednisolone and mycophenolate mofetil and within 12 weeks nephropathy and muscle weakness improved, as well as the skin rash. We review the existing literature regarding the concurrence of dermatomyositis and IgA nephropathy. The combination of these disorders in adult patients appears to be extremely rare, to our knowledge this is the third published case. In children there have been published another 3 cases. Although we cannot exclude a co-incidence that two disorders are found in the same patient, it seems more likely that a common pathological mechanism plays a role
Effects of Model Spatial Structure and Basin Characteristics on the Performance of Three Hydrologic Models
No full textHydrologic model selection plays a pivotal role in ensuring the reliability and accuracy of hydrologic modeling studies. This decision is mostly based on availability or researcher’s prior experience rather on a systematic evaluation of model structure and basin characteristics. This study aims to address this problem by comparing the effect of basin characteristics and hydrologic model structures on the streamflow prediction performance of lumped and distributed hydrologic models. For that, two lumped hydrologic models, Genie Rural à 4 Paramètres Journalier (GR4J) and Technische Universität Wien (TUW), and a distributed hydrologic model, mesoscale Hydrologic Model (mHM), are calibrated and validated in Dandalas subbasin, where Karacasu dam construction has taken place from 1998 to 2012, and in the karstic Çakıtsuyu subbasin. The model calibration was performed using the daily Nash-Sutcliffe Efficiency (NSE) as objective function whereas the validation performance was assessed with both daily and monthly NSE and Kling-Gupta Efficiency (KGE) metrics. Our results revealed the mHM model outperformed the other two models in both the calibration and validation periods in the karstic Çakıtsuyu subbasin, achieving the highest daily NSE during calibration (0.72) and validation (0.61). Notably, GR4J outperformed in Dandalas validation (KGE: 0.53 daily, 0.66 monthly). The superior performance of mHM can be attributed to its multi-parameter regionalization approach, detailed soil structure up to six horizons, elaborated flow routing scheme and representation of geological features using multiple karstic domains
Association of anesthesia strategies with outcomes in endovascular treatment for distal and medium vessel occlusions:A propensity score-matched analysis of the MR CLEAN registry and meta-analysis
No full textBackground: Recent trials did not demonstrate the benefit of endovascular therapy (EVT) for distal or medium vessel occlusions (DMVOs), raising questions about factors influencing outcomes. Anesthesia choice may play a role, yet its impact remains unclear. This study assessed general anesthesia (GA) versus non-GA in EVT for DMVOs, evaluating procedural, functional, and safety outcomes. Patients and methods: Patients undergoing EVT for AIS due to anterior DMVOs in the middle cerebral artery (MCA-M2, M3, M4) and anterior cerebral artery (ACA-A1, A2, A3) from the MR CLEAN registry between March 2014 and December 2018 were included. They were stratified into GA and non-GA groups, with propensity score matching employed to adjust for differences in baseline risk. Primary outcomes included functional outcomes at 90 days, assessed by ordinal regression analysis of modified Rankin Scale (mRS) scores at 90 days, and recanalization rates measured by Thrombolysis in Cerebral Infarction (TICI) scores. Secondary outcomes included dichotomized mRS scores, death at 90 days, and symptomatic intracranial hemorrhage (sICH). A systematic review and meta-analysis of relevant DMVO studies with a random effects model was performed. This study was registered with PROSPERO (CRD42024607294). Results: Among 5193 patients in the registry, 657 were eligible for our study, with 506 in the non-GA group, and 151 in the GA group. The median age was 73 years (IQR 64–81) in the non-GA group and 73 years (IQR 61–80) in the GA group (p = 0.35). The proportion of male patients was 50.2% in the non-GA group and 57.0% in the GA group (p = 0.15). In the matched cohort (n = 170), recanalization rates were higher in the GA group compared to the non-GA group (excellent recanalization rates (TICI2c/3): 61.0% vs 32.1%; OR 3.31, 95% CI (1.74–6.29), p < 0.001). There were no significant differences in the overall distribution of functional outcomes at 90 days (common OR 0.93, 95% CI (0.54–1.56), p = 0.77). Mortality was comparable between groups (34.1% vs 31.8%; OR 1.11, 95% CI (0.59–2.11), p = 0.74), and there was no significant difference in sICH (12.9% vs 5.9%; OR 0.42, 95% CI (0.14–1.27), p = 0.12). The systematic review and meta-analysis included six studies with a total of 3521 patients. The pooled analysis indicated that GA was associated with significantly lower rates of excellent functional outcomes (mRS 0–1: OR 0.74, 95% CI (0.58–0.94), p = 0.01) and higher mortality (OR 1.36, 95% CI (1.07–1.74), p = 0.01) compared to the non-GA at 90 days. Discussion and conclusion: In the MR CLEAN Registry, GA was associated with higher recanalization rates during EVT, but this technical advantage did not translate into improved 90-day functional outcomes. Our meta-analysis further indicated that non-GA strategies were associated with better functional recovery and lower mortality. These associations, however, warrant cautious interpretation given potential unmeasured confounders, including blood pressure management and conversion from non-GA to GA. Broad categorization of anesthesia as GA versus non-GA overlooks critical factors such as agent selection, physiological targets, and intraoperative monitoring, which may substantially impact cerebral perfusion and outcomes. Further prospective randomized studies with detailed anesthetic data and expert input are needed to refine these findings and guide clinical practice.</p
Design of a proof-of-concept demonstrator for an array-based in-ear active noise control device
No full textBuilding Resilience Together in the Face of Adversity:A Study of Entrepreneurial Teams
No full textEntrepreneurship is full of ups and downs, especially for entrepreneurial teams. Those downs can sometimes feel like hitting rock bottom—whether it's an unexpected crisis like a pandemic or ongoing pressure from market instability. Many new ventures fail when the going gets tough, but some teams manage to stay afloat and even thrive. This research explores how entrepreneurial teams can build and maintain resilience, giving them the tools to bounce back from abrupt challenges and sustain themselves through persistent adversity. The project is structured around four studies: the first explores how adversity rumination impacts individual entrepreneurial intentions, while the second provides a systematic literature review on the intersection of resilience and entrepreneurship. The third study focuses on the resilience pathways of entrepreneurial teams responding to abrupt adversity, and the fourth examines how teams sustain resilience during persistent adversity. The findings contribute to a deeper understanding of the cognitive and collective mechanisms that enable entrepreneurial teams to adapt and thrive under varying conditions of adversity
3D printing of foams for acoustic applications
No full textPolymer foams are widely used, forexample, to protect against shocks, for thermal insulation, or to reduce noisepropagation. Foams are usually produced in bulk, resulting in large slabs withhomogeneous properties yet locally polydisperse cell sizes. However, for mostapplications, gradients are highly beneficial as these allow locally tailoringthe response of the foam to mechanical compression. In this thesis, a novelfoam manufacturing technique named “Direct Bubble Writing” is explored to 3D-printfoam parts with internal density gradients, controlled cell size, and aprescribed outer shape, and their acoustic performance is tested.The direct bubble writing technologyuses a core-shell nozzle that dispenses a stream of gas-filled liquid bubbles.As these bubbles flow down, exposure of the stream to the UV lights initiatesthe polymerization in the bubble shells on-the-fly. The bubble shells arepolymerized to hold their shape and are stacked together to produce 3D foamarchitectures. The moving axes of the printer enable one-step fabrication of3D designs accessible including hollow or solid designs with cylindrical orsquare cross-sections. This thesis first describes the stateof the art of materials for sound transmission loss in Chapter 2. Subsequently,in Chapter 3, a range of UV-curable resins for fabrication of micro-materialsis developed, including resins based on acrylates and thiol-enes. Chapter 4describes how the direct bubble writingprocess was optimized by systematically assessing the design parameters forprinting uniform and density gradient structures. In chapter 5, the controlparameters of foam printing (e.g. the type of gas and the gas flow rate) weresystematically varied to create samples with controlled gradients. The printedfoams are tested for sound transmission loss (STL), revealing a maximum STL of 25 dB for homogeneous foamsat frequencies around 2600 Hz. However, sandwich-inspired gradient foamsenhance the STL to exceed 60 dB for frequencies around 2400 Hz. These foamsalso exhibit broadband acoustic absorption (~0.65) for frequencies between 300and 2600 Hz. Thus, direct bubble writing is a promising platform to producecustom (gradient) design lightweight porous acoustic materials for broadbandsound transmission loss at low frequencies.</p
Novel targeting strategies to reprogram cancer-associated fibroblasts in the tumor microenvironment
No full textThe tumor microenvironment (TME) is a critical driver of cancer progression, metastasis, and therapeutic resistance. Among its various cellular components, cancer associated fibroblasts (CAFs) are particularly essential due to their ability to remodel the extracellular matrix (ECM), secrete growth factors and cytokines, and interact with other cell types to promote tumorigenesis. The heterogeneity of CAFs, increasingly recognized as subtypes including myofibroblastic CAFs (myCAFs) and inflammatory CAFs (iCAFs), adds complexity to their role in cancer biology. This diversity also complicates the therapeutic potential, yet targeting CAFs has emerged as a promising strategy to overcome the therapeutic resistance associated with the TME. However, the development of effective therapies is challenging due to the complex interactions between CAF subtypes, immune cells, and tumor cells. This dissertation addresses these challenges by exploring innovative approaches to selectively target different CAF subtypes, aiming to disrupt their pro-tumorigenic functions and improve the efficacy of chemotherapy. The first part of this dissertation discusses the biology of CAFs as well as potential therapeutic strategies. Special attention is given to pancreatic ductal adenocarcinoma (PDAC), one of the most desmoplastic tumors, underscoring the importance of developing biologically relevant models that reflect the TME complexity. The second part of this dissertation introduces a polymeric nanofiber system designed for the controlled co-delivery of a p21-activated kinase 1 inhibitor, FRAX597, and the chemotherapeutic agent paclitaxel. This system was tested in stroma-rich breast cancer models highlighting the potential of targeting CAFs to overcome chemoresistance in solid tumors. In the third part, integrins α5 and α11 were identified as potential drug delivery targets for iCAFs/myCAFs and myCAFs only, respectively. Utilizing novel peptides AV3 and AXI, surface-functionalized polymeric nanoparticles showed selective targeting and enhanced PDAC biodistribution. Building on this, the fourth part investigates the therapeutic efficacy of these nanoparticles in delivering a monoacylglycerol lipase inhibitor, URB602 and an aryl hydrocarbon receptor agonist, YL109 to CAF subtypes, resulting in TME modulation in preclinical KPC model. Finally, the fifth part explores the potential of specific targets inhibition within CAFs, including fibroblast growth factor receptor-4 and dipeptidyl peptidase-4, demonstrating therapeutic suppression of iCAFs, myCAFs and significant modulation of PDAC TME
