Sub-Riemannian heat kernels and mean curvature flow of graphs

We introduce a sub-Riemannian analogue of the Bence-Merriman-Osher diffusion driven algorithm and show that it leads to weak solutions of the horizontal mean curvature flow of graphs over sub-Riemannian Carnot groups. The proof follows the nonlinear semi-group theory approach originally introduced by L. C. Evans in the Euclidean setting and is based on new results on the relation between sub-Riemannian heat flows of characteristic functions of subgraphs and the horizontal mean curvature of the corresponding graphs.Comment: 24 page

From Chirps to Random-FM Excitations in Pulse Compression Ultrasound Systems

Pulse compression is often practiced in ultrasound Non Destructive Testing (NDT) systems using chirps. However, chirps are inadequate for setups where multiple probes need to operate concurrently in Multiple Input Multiple Output (MIMO) arrangements. Conversely, many coded excitation systems designed for MIMO miss some chirp advantages (constant envelope excitation, easiness of bandwidth control, etc.) and may not be easily implemented on hardware originally conceived for chirp excitations. Here, we propose a system based on random-FM excitations, capable of enabling MIMO with minimal changes with respect to a chirp-based setup. Following recent results, we show that random-FM excitations retain many advantages of chirps and provide the ability to frequency-shape the excitations matching the transducers features.Comment: 4 pages, 4 figures. Post-print from conference proceedings. Note that paper in conference proceedings at http://dx.doi.org/10.1109/ULTSYM.2012.0117 has some rendering issue

An Alternative Phase-Sensitive THz Imaging Technique for Art Conservation: History and New Developments at the ENEA Center of Frascati

In recent years, THz imaging techniques have been used in several fields of application. At the beginning of the century, the low availability of powerful THz sources was one of the limiting factors to the advancement of THz technology. At the ENEA center in Frascati, two Free Electron Lasers (FELs) operating in the THz spectral region were available at that time, making it possible to exploit all the features of THz imaging. In this paper, we will describe an alternative THz imaging technique, developed over 15 years of studies at the ENEA center of Frascati, and its application in the art conservation field, reporting the latest results of such studies on the optical properties of pigments in the GHz-THz region of the spectrum, on the possibility of detecting biological weeds under mosaic tiles and on the THz analysis of ancient leather wallpapers. This alternative technique was first developed in the framework of a bilateral collaboration between Japan and Italy, the THz-ARTE Project, which involved NICT (Tokyo), NNRICP (Nara), ENEA (Frascati) and IFAC-CNR (Florence). Most of the THz imaging techniques at that time were based on THz-Time Domain (THz-TD) devices. In the paper will be described how this alternative technique is able to measure the phase of the reflected radiation, thus providing information on the optical properties of the materials under study, such as mural paintings and mosaics. This makes it possible to detect the presence of hidden artworks, additional elements under paint layers, and dielectric materials. To describe the potential and the limits of this alternative imaging technique we will start from a description of the first THz imaging setup at the ENEA center of Frascati, based upon a THz Free Electron Laser. A description of the theoretical principle underlying this technique will be given. The first results in the field of art conservation are summarized, while the new results of a systematic study on the optical properties of pigments are reported and the realization of a portable THz imaging device, and its application "on site" for the analysis of frescoes are shown. The success of this prototype lead to the identification of different types of artworks as possible targets to be studied. New results about the ability of detecting water, and possibly the water content of biological weeds, under mosaic tiles are described, while new experimental measurements on Leather Wallpapers, both "in situ" and in a laboratory environment, are discussed later. A final analysis on the pro and the cons of this alternative imaging technique and on its possible utilization with the developed prototype is carried out together with the considerations on possible future developments and its potential use as an extension of other imaging techniques

Treating Patients Following Hospitalisation for Acute Decompensated Heart Failure: An Insight into Reducing Early Rehospitalisations

Heart failure (HF) is a pandemic syndrome characterised by raised morbidity and mortality. An acute HF event requiring hospitalisation is associated with a poor prognosis, in both the short and the long term. Moreover, early rehospitalisation after discharge negatively affects HF management and survival rates. Cardiovascular and non-cardiovascular conditions combine to increase rates of HF hospital readmission at 30 days. A tailored approach for HF pharmacotherapy while the patient is in hospital and immediately after discharge could be useful in reducing early adverse events that cause rehospitalisation and, consequently, prevent worsening HF and readmission during the vulnerable phase after discharge

Healthcare Service Quality Evaluation in a Community-Oriented Primary Care Center, Italy

Community-oriented primary care (COPC) is an inclusive healthcare approach that combines individual care with a population-based outlook, striving to offer effective and equitable services. This study concentrates on assessing the perceived quality of a "Casa della Comunita" (CdC) implemented by the Romagna Local Health Authority, which embraces the COPC model. Through the examination of user experiences, the study aims to comprehend the influence of the CdC's care delivery model on the community's perception of service quality. From 13-18 March 2023, paper questionnaires were distributed by trained healthcare professionals and volunteers. The cross-sectional study enrolled participants aged 18 or older, capable of understanding written Italian, and willing to take part voluntarily. A total of 741 questionnaires were collected, resulting in an overall acceptance rate of 85.6%. Among the respondents, 37.9% were female, with an average age of 55.4 & PLUSMN; 16.2 years. While the respondents generally held a positive view of the quality, the results displayed varying levels of satisfaction across the different areas. Multivariate analysis revealed significant associations between factors such as gender, employment status, financial resources, education level, and distance from the healthcare center with the perceived quality of the facility in terms of accessibility, environment, staff, continuity of care, and overall satisfaction. The study yielded valuable insights, identifying strengths and areas for improvement and underscoring the importance of ongoing monitoring studies to enhance patient satisfaction continuously

Long‐term outcomes of phenoclusters in preclinical heart failure with preserved and mildly reduced ejection fraction

Aims The identification of subjects at higher risk for incident heart failure (HF) with preserved ejection fraction (EF) suitable for more intensive preventive programmes remains challenging. We applied phenomapping to the DAVID-Berg population, comprising subjects with preclinical HF, aiming to refine HF risk stratification. Methods The DAVID-Berg study prospectively enrolled 596 asymptomatic outpatients with EF > 40% with hypertension, diabetes mellitus or known cardiovascular disease. In this cohort, we performed an unsupervised cluster analysis on 591 patients, including clinical, laboratory, electrocardiographic and echocardiographic parameters. We tested the association between each cluster and a composite outcome of HF/death. Results The median age was 70 years, 55.5% were males and the median EF was 61.0%. Phenomapping provided three different clusters. Subjects in Cluster 3 were the oldest and had the highest prevalence of atrial fibrillation, the lowest estimated glomerular filtration rate (eGFR), the highest N-terminal pro-brain natriuretic peptide (NT-proBNP) and the largest left atrium. During a median follow-up of 5.7 years, 13.4% of subjects experienced HF/death events (N = 79). Compared with Clusters 1 and 2, Cluster 3 had the worst prognosis (log-rank test: Cluster 3 vs. 1 P < 0.001; Cluster 3 vs. 2 P = 0.008). Cluster 3 was associated with a risk of HF/death 2.5 times higher than Cluster 1 [adjusted hazard ratio (HR) = 2.46, 95% confidence interval (CI) 1.24-4.90]. Conclusions Based on phenomapping, older patients with lower kidney function and worse diastolic function might represent a subset of preclinical HF with EF > 40% who deserve more efforts to prevent clinical HF

How future surgery will benefit from SARS-COV-2-related measures: a SPIGC survey conveying the perspective of Italian surgeons

COVID-19 negatively affected surgical activity, but the potential benefits resulting from adopted measures remain unclear. The aim of this study was to evaluate the change in surgical activity and potential benefit from COVID-19 measures in perspective of Italian surgeons on behalf of SPIGC. A nationwide online survey on surgical practice before, during, and after COVID-19 pandemic was conducted in March-April 2022 (NCT:05323851). Effects of COVID-19 hospital-related measures on surgical patients' management and personal professional development across surgical specialties were explored. Data on demographics, pre-operative/peri-operative/post-operative management, and professional development were collected. Outcomes were matched with the corresponding volume. Four hundred and seventy-three respondents were included in final analysis across 14 surgical specialties. Since SARS-CoV-2 pandemic, application of telematic consultations (4.1% vs. 21.6%; p < 0.0001) and diagnostic evaluations (16.4% vs. 42.2%; p < 0.0001) increased. Elective surgical activities significantly reduced and surgeons opted more frequently for conservative management with a possible indication for elective (26.3% vs. 35.7%; p < 0.0001) or urgent (20.4% vs. 38.5%; p < 0.0001) surgery. All new COVID-related measures are perceived to be maintained in the future. Surgeons' personal education online increased from 12.6% (pre-COVID) to 86.6% (post-COVID; p < 0.0001). Online educational activities are considered a beneficial effect from COVID pandemic (56.4%). COVID-19 had a great impact on surgical specialties, with significant reduction of operation volume. However, some forced changes turned out to be benefits. Isolation measures pushed the use of telemedicine and telemetric devices for outpatient practice and favored communication for educational purposes and surgeon-patient/family communication. From the Italian surgeons' perspective, COVID-related measures will continue to influence future surgical clinical practice

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Moisture content and strain relation in wood by Bragg grating sensor and unilateral NMR

The paper describes a low-invasive experimental apparatus designed for the accurate determination of mechanical deformation and moisture content (MC) relationship on macroscopic wood samples. The device is particularly indicated for monitoring wooden handwork whose mechanical deformation is especially critical in relation to its role such as, for example, works of art or architectural works. The MC of wood is measured with a portable single-sided NMR probe and mechanical deformation by a fiber Bragg grating optical sensor. The data obtained are of high accuracy, despite the dimensions of the sample. The methodology provides an effective tool for investigating the dynamic relation between environmental relative humidity, MC, and shrinking-swelling of wood. Adsorption results collected for longitudinal deformation in silver fir (Abies alba Mill.) are presented to show the sensitivity of the optical sensor. Interesting findings include the detection of two different mechanisms of elongation and the time evolution of water mobility versus hydration and strain