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E-bikes’ impact on job accessibility and equity in São Paulo and Rio
No full textDespite their ability to address challenges associated with conventional cycling, the potential of e-bikes to improve accessibility to opportunities and equity remains largely unexplored. This study addresses this gap by evaluating e-bikes’ impacts on job accessibility and spatial equity in São Paulo and Rio de Janeiro, Brazil’s two largest cities. We calculated cumulative accessibility using different thresholds of travel time and physical effort, which were modeled using GPS data from a bike-sharing system. Results reveal that e-bikes significantly enhance job accessibility compared to conventional bicycles, particularly for longer cycling trips and trips in hilly areas. However, accessibility gaps persist in peripheral neighborhoods. Equity analyses using Moran’s Index and the Concentration Index demonstrate that e-bikes reduce spatial disparities, benefiting lower-income groups, though absolute inequalities persist. Urban topography and structure critically shape outcomes, meaning that the impact of e-bikes varies both between and within cities
Pelvic organ prolapse and pressary treatment:Insights with upright MRI
No full textPelvic organ prolapse (POP) is a prevalent condition among middle-aged women worldwide, often impairing quality of life through symptoms such as pelvic pressure, bulging sensation, and urinary or defecatory dysfunction. This thesis focuses on the assessment of POP and the mechanisms underlying successful pessary therapy, using upright magnetic resonance imaging (MRI) to gain novel anatomical and functional insights.The first part of the thesis investigates pelvic anatomy in relation to POP assessment. Comparison between the Pelvic Organ Prolapse Quantification (POP-Q) System and upright MRI demonstrated a moderate correlation but considerable individual variation, indicating that POP-Q may underestimate organ descent—particularly in stage 1 prolapse. Upright MRI thus provides a more physiological assessment of pelvic organ position. Subsequent studies showed limited average anatomical variation during the day; however, individual fluctuations in POP extent of up to 2.2 cm were observed, emphasizing the dynamic nature of pelvic support. Furthermore, after pessary removal, a delayed descent of the pelvic organs was detected in several patients, supporting the recommendation to postpone POP quantification for at least eight hours post-pessary-removal to ensure accuracy.The second part of the thesis addresses pessary treatment mechanisms. Upright MRI analyses of successful pessary users refuted the hypothesis of bony support, instead revealing that the pessary is primarily supported by the levator ani muscle (LAM) and potentially stabilized by the uterus acting as a lever. Comparative evaluation between successful and unsuccessful users confirmed this mechanism, as unsuccessful cases exhibited lower pessary positioning and suboptimal alignment with the LAM and uterus.Finally, anatomical effects of pessary insertion were quantified: while both bladder and uterus were elevated after insertion, only uterine elevation persisted after one week, suggesting that sustained uterine repositioning may be central to symptomatic improvement.In conclusion, this thesis enhances understanding of pelvic anatomy and pessary biomechanics in POP. Upright MRI proves to be a valuable imaging modality for anatomic pelvic assessment and may contribute to the optimization of personalized pessary design and improved treatment outcomes.<br/
Ground instability effects
Get PDFThis chapter is conceived to describe methodologies for the generation of scenarios having as effects ground deformation processes (landslides, subsidence and underground cavity collapses) triggered by different inputs. Special attention has been devoted to products for the aware management of the territory and to define strategies for the community resilience. The natural processes responsible for ground instability effects (i.e. landslides, subsidence and collapses) are here framed from a phenomenological perspective but also with reference to their temporal recurrence and spatial distribution on a global scale. The quantification of ground instability effects is connected to the analysis of their recurrence and activity as well as to the relevance of distinguishing macro-factors (predisposing, preparatory and triggering) necessary to define their efficiency in time and space. The chapter provides a state of art regarding methodological approaches which, through statistical and probabilistic approaches, allow the rendering of scenarios for the effects connected to ground instability at various scales for land management and the definition of strategies for the community resilience. The treatise can be supported by the citation of case studies. Particular attention has been paid to the distinction (where applicable) among the functional approaches to the analysis of the spatiotemporal distribution of predisposing, preparatory and triggering factors in the perspective of quantitative risk analyses.</p
Influence of surfactant kinetics on rapid interface creation via microjet impact on liquid pools
Get PDFWe experimentally investigate the influence of surfactant adsorption kinetics on cavity dynamics during the rapid formation of interfaces. For this purpose, we use a submillimeter jet impacting onto a surfactant-laden liquid pool much larger than the jet dimensions. Cavity retraction and closure occur on a submillisecond timescale, posing a stringent test of the ability of surfactants to reduce surface tension dynamically. Our experiments reveal the difference between the effects of sodium dodecyl sulfate (SDS), a surfactant with moderately fast adsorption kinetics, and Surfynol 465, a surfactant with ultrafast adsorption kinetics. For SDS, the collapse pathway is nearly indistinguishable from that of pure water, suggesting negligible dynamic surface tension reduction. In contrast, Surfynol allows the emergence of deeper cavities that persist longer in the liquid pool. The harmonic oscillator model accurately captures the cavity retraction in the deep seal regime. The fitted values of the damping ratios are consistent with the dynamic surface tensions
From Classical Rationality to Contextual Reasoning:Quantum Logic as a New Frontier for Human-Centric AI in Finance
Get PDFWe consider state-of-the-art applications of artificial intelligence (AI) in modelling human financial expectations and explore the potential of quantum logic to drive future advancements in this field. This analysis highlights the application of machine learning techniques, including reinforcement learning and deep neural networks, in financial statement analysis, algorithmic trading, portfolio management, and robo-advisory services. We further discuss the emergence and progress of quantum machine learning (QML) and advocate for broader exploration of the advantages provided by quantum-inspired neural networks. These benefits arise from quantum logic’s ability to capture agents’ non-classical expectations and non-expected utility decisions, often referred to as ‘bounded rationality’. We present illustrative examples of expectation formation schemes in asset trading, grounded in quantum probability theory. We argue that quantum-based models hold significant potential to replicate human cognitive processes, enhance AI efficiency, and improve functionality in complex and uncertain environments. Ultimately, we aim to promote the adoption of quantum-driven AI techniques to improve upon classical models in capturing human-like decision-making
The promises and perils of online labor platforms for the sustainable inclusion of people with a disability
No full textCombined Lung and Kidney Support in a Single Extracorporeal Device:Development of The First RenOx Prototype
No full textENDORISK-2:A personalized Bayesian network for preoperative risk stratification in endometrial cancer, integrating molecular classification and preoperative myometrial invasion assessment
Get PDFBackground: ENDORISK is a Bayesian network that can assist in preoperative risk estimation of lymph node metastasis (LNM) risk in endometrial cancer (EC) with consistent performance in external validations. To reflect state of the art care, ENDORISK was optimized by integrating molecular classification and preoperative assessment of myometrial invasion (MI).Methods: Variables for POLE , MSI, and preoperative assessment of MI, either by expert transvaginal ultrasound or pelvic magnetic resonance imaging (MRI), were added to develop ENDORISK-2. The p53 biomarker, part of the molecular classification, was already included in ENDORISK. External validation of ENDORISK-2 for LNM prediction was performed in two independent cohorts from: Brno (CZ), (n = 581) and Tübingen (DE), (n = 247).Findings: ENDORISK-2 yielded AUCs of 0·85 (95 % CI 0·80–0·90) (CZ) and 0·86 (95 % CI 0·77–0·96) (DE) for predicting LNM. In patients with low-grade histology, 83 % (CZ) and 89 % (DE) were estimated having less than 10 % risk of LNM, with false negative rates (FNR) of 4·3 % (CZ) and 2·2 % (DE). The previously defined set of minimally required variables, i.e.: preoperative tumor grade, three of the four immunohistochemical (IHC) markers, and one clinical marker, could be interchanged with the new variables, with comparable validation metrics, including AUC values of 0·79–0·87 for LNM prediction.Interpretation: Incorporation of molecular data and preoperative MI improved the flexibility of ENDORISK with comparable diagnostic accuracy for estimating LNM as when based on low-cost immunohistochemical biomarkers. In addition, the high diagnostic accuracy in patients with low-grade EC demonstrates how ENDORISK-2 could aid clinicians in identifying patients in whom surgical lymph node assessment may safely be omitted. These results underline its power for clinical use in both high and low resource countries.</p
Exploring liquid fuel combustion dynamics in a swirl burner using dynamic mode decomposition
Get PDFAero gas turbine engine combustors are transitioning from traditional Rich-Quench-Lean (RQL) staging to Lean Premixed Prevaporized (LPP) operation to reduce harmful NOx emissions and improve combustion efficiency. This operational shift, however, introduces the risk of thermoacoustic instabilities, a significant concern for reliable operation and integrity of the jet fuel fired aero gas turbines. Moreover, the complex geometries of aero engine combustors and the challenges of partially premixed conditions further complicate stability analysis and demand advanced diagnostic techniques. To that end, this work aims to analyse thermoacoustic and swirl burner instabilities of our in-house designed Magister burner under engine representative lean conditions using Detached Eddy Simulation. We extended our prior analysis by applying Dynamic Mode Decomposition (DMD) in a distributed computing environment, leveraging our PARAMOUNT modal analysis package, to capture the burner's critical acoustic and transient dynamics. The proposed novel DMD combined spectrum effectively identified the mechanism driving vortex core rotation, capturing its frequency to within (Formula presented.) of the measured value. It was demonstrated that using Proper Orthogonal Decomposition (POD) modes directly is more effective than an exact DMD formulation, yielding a (Formula presented.) reduction in the Mean Absolute Error (MAE) of DMD predicted temperature values. Furthermore, the application of variable stacking reduced the MAE of the short-term DMD temperature predictions by (Formula presented.). Finally, an MRDMD adjustment is proposed that leverages a critical Strouhal number (St = 0.6) to significantly enhance ROM by ensuring essential flow dynamics are retained. This novel analysis framework demonstrates a powerful capability to assess thermoacoustic stability, extracting critical physical insights from complex simulations that produce large datasets and thereby accelerating the design cycle for aero-engine combustors.</p
Prediction of the Shape of Severely Fractured Distal Tibia by Using Statistical Shape Modelling
Get PDFThe design of tibial components of ankle implants is critical for proper functioning. The tibial component design uses the shape of the distal tibial bone as reference. However, when the distal tibia is severely damaged or fractured, the design of tibial components becomes very difficult. In this paper, we aim to study prediction of the distal tibia shape based on the remainder of tibial bone. We use statistical shape modelling technique to create a model of the tibial bone, and then we assess its shape variability. We extract the relationships between the shape variations to produce the predictions. A dataset of 22 female bone samples and 30 male bone samples were acquired. A statistical shape model per gender was produced by using a part of the dataset population. The first set of principal component analysis modes accounted for at least 95% of the shape variations were adopted. For the rest of the bone samples, we attempted to predict their distal tibia shapes by feeding the shapes of their proximal tibia and tibial shafts into the models. The prediction was done for roughly up to 20 mm above the distal tibial articular surface. The study was done in a 5-fold cross validation setting. Root-mean-square errors of reconstruction of the samples excluded in the model development were 1.91 ± 0.61 mm and 2.01 ± 0.39 mm for females and males, respectively. The prediction errors of the distal tibia, when only the shape of the proximal tibia and tibial shafts were known, were in average 1.96 mm for female’s bones and 2.46 mm for male’s bones. These small errors can show that the distal tibia shape can be reconstructed based on the proximal and shaft shapes. This is a preliminary result bringing new insights into treatment of ankle orthopaedic diseases. It can pave the way for reconstruction of lost distal tibia.</p