Archivio della ricerca della Scuola Superiore Sant'Anna
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Echocardiographic Screening for Transcatheter Edge-to-Edge Mitral Valve Repair: Correlation Between Transthoracic and Transesophageal Assessment
Get PDFBackground: In patients with significant mitral regurgitation (MR) undergoing transcatheter edge-to-edge repair (M-TEER), assessment of mitral valve (MV) anatomy is essential. While transthoracic echocardiography (TTE) is the initial diagnostic tool, transesophageal echocardiography (TOE) provides better anatomical details. The study aims to assess whether TTE is as effective as TOE in selecting patients with severe MR who are eligible for M-TEER. Methods: From January to December 2024, patients with severe MR eligible for TEER were enrolled at the Fondazione Monasterio Heart Hospital, Italy. They underwent a comprehensive TTE and TOE examination. Cardiologists assessed the severity of MR and valve anatomy using specific protocols. Measurements included MV area, MV gradient, posterior leaflet length, fossa ovalis high, presence of fails, clefts, and calcifications. Three levels of anatomic complexity were defined to determine eligibility for TEER. Results: The study includes 40 patients with severe MR. The correlation between TTE and TOE for key parameters was strong, with coefficients ranging from 0.734 to 0.901, indicating high agreement between the two methods. The comparison of categorical features showed high agreement between TTE and TOE in detecting critical MV conditions, with kappa values ranging from 0.717 to 0.930. The agreement for classifying patients as suitable for M-TEER was 87.5%, indicating moderate consistency between the two methods. Conclusions: TTE may be a viable alternative to TOE for assessing MV anatomy and function before M-TEER in MR patients, especially in high-volume centers. While TTE strongly correlated with TOE for most parameters, TOE was superior for some features. Further research is needed to refine the clinical application of TTE and to define patient selection criteria for its use as the primary imaging modality for pre-procedural M-TEER screening
A New Twist on Low-Complexity Digital Backpropagation
Get PDFThis work proposes a novel low-complexity digital backpropagation (DBP) method, with the goal of optimizing the trade-off between backpropagation accuracy and complexity. The method combines a split step Fourier method (SSFM)-like structure with a simplified logarithmic perturbation method to obtain a high accuracy with a small number of DBP steps. Subband processing and asymmetric steps with optimized splitting ratio are also employed to further reduce the number of steps required to achieve a prescribed performance. The first part of the manuscript is dedicated to the derivation of a simplified logarithmic-perturbation model for the propagation of a dual-polarization multiband signal in an optical fiber, which serves as a theoretical background for the development of the proposed coupled-band enhanced split step Fourier method (CB-ESSFM) and for the analytical calculation of the model coefficients. Next, the manuscript presents a digital signal processing algorithm for the implementation of DBP based on a discrete-time version of the model and an overlap-and-save processing strategy. Practical approaches for the optimization of the coefficients used in the algorithm and of the splitting ratio of the asymmetric steps are also discussed. A detailed analysis of the computational complexity of the algorithm is also presented. Finally, the performance and complexity of the proposed DBP method are investigated through numerical simulations and compared to those of other methods. In a five-channel 100 GHz-spaced wavelength division multiplexing system over a 15×80 km single-mode-fiber link, the proposed CB-ESSFM achieves a gain of about 1 dB over simple dispersion compensation with only 15 steps (corresponding to 681 real multiplications per 2D symbol), with an improvement of 0.9 dB over conventional SSFM and almost 0.4 dB over our previously proposed ESSFM. Significant gains and improvements are obtained also at lower complexity. For instance, the gain reduces to a still significant value of 0.34 dB when a single DBP step is employed, requiring just 75 real multiplications per 2D symbol. A similar analysis is performed also for longer links, confirming the good performance of the proposed method
Systemic Risk Management and Stakeholder Engagement: Insights From Business CSR Disclosure
No full textThis study investigates corporate strategies for integrating non-financial risks and stakeholder engagement into business man-agement frameworks. Our inquiry analyzes the extent to which companies explicitly or implicitly incorporate stakeholderperspectives into their risk management practices. Based on the four fundamental pillars of risk management outlined by theInstitute of Risk Management (IRM 2002), this study seeks to elucidate the multidimensional and comprehensive nature ofstakeholder engagement in risk management processes. This study is based on a content analysis of 253 sustainability reports andNon-Financial Statements drawn from different categories of companies representing the Italian market: large companies, smalland medium-sized enterprises (SMEs), cooperatives, and public utilities. The results reveal that companies primarily address riskmanagement and control in their reports, aligning with the literature. Although risk components are equally important in man-aging adverse events, the results show a high percentage of risk analysis unlike what emerged from the literature, and a smallerpercentage of companies focused on risk monitoring and risk communication. Stakeholder engagement levels vary based oncompany type and the activities performed in the risk governance process. From a theoretical perspective, this study contributesto systemic risk management research by integrating stakeholders into risk governance models. From a managerial perspective,this study offers implications for both risk management and sustainability disclosure practices. Limitations include the sample ofItalian companies only and the different publication years of the collected reports
Exploring the role of staffing needs in JD-R theory: evidence from public healthcare organizations
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Late Gadolinium Enhancement Dispersion for predicting malignant arrhythmic events in patient with non-ischemic Dilated Cardiomyopathy
No full textGenetic basis of Fusarium ear rot resistance and productivity traits in a heterozygous multi-parent recombinant inbred intercross (RIX) maize population
Get PDFMaize (Zea mays L.) is one of the most productive crops worldwide. As a heterotic crop predominantly grown as F1 hybrid, maize exhibits challenges for genetic studies of complex traits, since homozygous genotypes, which are largely used in these studies, may not accurately reflect what happens in cultivated conditions. To map Fusarium Ear Rot (FER) resistance to Fusarium verticillioides and traits with potential impact on yield, including phenology, we constructed a recombinant intercross (RIX) population. This was achived by crossing pairs of recombinant inbred lines (RILs) derived from a multi-parent maize population. We characterized the RIX population over two growing seasons, employing artificial F. verticillioides inoculation. The heterozygous background of the material enabled the identification of QTL and candidate genes through in silico reconstruction of RIX genotype probabilities. A total of 37 loci were identified using single-year BLUPs while 29 with joint-year BLUPs. These, included several known QTL associated with days to tasseling, kernel row number and a QTL on the chromosome 9 associated with FER resistance. In this region, we could identify candidates based on their predicted functions and potential roles in plant-pathogen interactions and/or resistance mechanisms. These QTL represent potential breeding targets to FER resistance and yield components in commercial maize varieties
THE EUROPEAN COUNCIL: TRULY THE LAW-MAKER-IN-CHIEF?
Get PDFWe know that the European Council is a powerful and visible strategic agenda-setter, crisis
manager, and impasse-breaker. Yet we are less familiar with the role of national heads of
state or government in everyday law-making. By analysing all legislation under the
ordinary legislative procedure since 1999, this CEPS Explainer asks whether and – if so –
how and how often the European Council refers to these specific laws in its summit
conclusions.
We show that the European Council mentions about 20% of all legislation and especially
prioritises laws that redistribute money, expand EU competences and respond to a
specific crisis. On prioritised laws, the European Council mandates the EU’s other
institutions and Member States and acts actively and assertively across all stages of the
policy process. This is the case even on priorities not shared with the European
Commission as the legislative agenda-setter.
In short, this Explainer puts the spotlight firmly on the national leaders who run the show
– not just in large, visible summits but also during the follow-up everyday law-making
proces