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Quantitative fluorescence spectroscopy requires corresponding reflectance measurements to correct for tissue absorption and scattering. However, it is unclear whether fluorescence adds value beyond the diffuse reflectance measurements necessary for correction. The goal of this study was to compare the accuracy of fluorescence and diffuse reflectance spectroscopy in recovering the concentration of a high-extinction fluorophore, methylene blue (MB), using a compact fiber-optic probe. Fluorescence and diffuse reflectance measurements of tissue simulating phantoms were made using a fiber-optic probe with source-detector separations of 288-1300 μm. Average error in recovered fluorophore concentration was 20.4% for fluorescence and 15.0% for reflectance, though this difference was not significant (p=0.77). Both methods returned concentrations that were similar to known MB concentrations (p≥0.79 in both cases). Fluorescence quantification of the concentration of a high extinction fluorophore did not significantly improve accuracy relative to diffuse reflectance. Investigators should consider whether fluorescence measurements are necessary for a given application.

Introduction Left atrial appendage closure (LAAC) is an emerging option in patients with atrial fibrillation (AF) and contraindication for oral anticoagulation (OAC) therapy. Patients with left atrial thrombus are usually excluded from this strategy. Therefore, pre-procedural transesophageal echocardiography (TEE) is usually performed for LAA thrombus exclusion. The application of second-generation lipid microspheres ultrasound enhancing agents (UEA) is of growing interest. The following clinical cases reports describe the benefit from UEA implication on subsequent decision-making regarding with LAAC procedure. Case report num.1 an 88-year-old male with history of symptomatic AF and post – traumatic cerebral bleeding was referred to LAAC because of high risk of bleeding in using OAC. Transthoracic echocardiography (TTE) documented a severely dilatated left atrium and preserved left ventricular systolic function. Pre – operative TEE revealed a “chicken wing” shaped LAA with severe spontaneous echo-contrast and sludge effect. Echo-contrast medium “SonoVue” showed an early filling defect with late but complete LAA opacification, excluding thrombus. Of note, ECG-gated cardiac CT (CCT) could not exclude filling defect with certainty. Consecutively, the patient was candidate to LAAC in a short time. Case report num.2 a 75-year-old man with valvular permanent AF and multi-territory ischemic ictus despite being on adequate prophylactic OAC (Warfarin). At TTE a dilated left ventricle with mildly reduced ejection fraction was documented. ECG – gated CCT with delayed phases imaging showed a possible filling defect in LAA, however imaging was suboptimal due to a reverb of voluminous hiatal hernia. TEE revealed a “windstock” shaped LAA with incomplete distal opacification when echo-contrast medium “SonoVue” was used, confirming thrombus. The patient was therefore referred for LAAC procedure with concomitant use of cerebral embolic protection devices (CEPDs). Discussion Transesophageal echocardiography is the test of choice for the exclusion of LAA thrombus. However technical difficulty, spontaneous echo contrast (SEC) and prominent pectinate musculature within the appendage may make the exclusion of LAA thrombus not easy. ECG – gated cardiac CT may be conclusive as well. UEA use is associated with higher diagnostic power for LAA thrombus exclusion and recent study have shown its utility also in terms of LAA sizing. Thus, the most recent guidelines of American Society of Echocardiography mention echo contrast use for the delineation of LAA thrombi and differentiate between them with SEC. Conclusion The use of ultrasound enhancing agents is useful and increases the interpretative confidence in exclusion of LAA thrombus.

Introduction Percutaneous left atrial appendage closure (LAAC) in AF patients is not inferior to oral anticoagulation (OAC) in terms of systemic embolism. LAA Closure is usually contraindicated in presence of intracardiac thrombus, a condition far from uncommon. The feasibility and safety of transcatheter cerebral embolic protection (TCEP) has been reported in literature as a successful off – label option in retrieving embolic debris during percutaneous LAAC. We present two cases of Watchman Flex insertion in the setting of LAA thrombus and prophylactic use of TCEP. Cases report The first patient was an 88-year-old male with history of symptomatic AF and post – traumatic cerebral bleeding, who was referred to LAAC because of high risk of bleeding in using OAC. Transthoracic echocardiography (TTE) documented a severely dilatated left atrial and preserved left ventricular systolic function. Transesophageal echocardiography (TEE) revealed a “chicken wing” shaped LAA with spontaneous echo-contrast and sludge effect confirmed with echo-contrast medium “SonoVue”. ECG – gated cardiac CT (CCT) showed a LAA filling defect and confirmed the diagnosis of LAA thrombus. The second patient was a 75-year-old man with valvular permanent AF and history of multiple ischemic strokes despite of OAC therapy with Warfarin. TTE documented a dilated left ventricle with severely depressed ejection fraction; TEE revealed a “windstock” shaped LAA with incompletely distal opacification with echo-contrast medium “SonoVue”. Both patients were candidate to LAAC with concomitant use of CEPDs in the event of neurological complication. TriGUARD 3 cerebral protection (TG3, Keystone Heart) was deployed in the aortic arch through right femoral artery access before LAAC procedure. Following transseptal puncture Watchman Flex device (Boston Scientific, Marlborough, MA) was deployed without complications or residual peri-device leaks. At the end the TriGurad 3 device was retracted and no debris were noted at the post operatory inspection. The first patient was discharged afterward with daily acetylsalicylic acid 100 mg and Clopidogrel 75 mg and the second patient with daily acetylsalicylic acid 100 mg and Warfarin. Both patients underwent follow-up TEE at four weeks. Neither device – related complications nor thrombotic/hemorrhagic adverse events have been not reported so far. Discussion Both patients were at very high risk for stroke and bleeding. They were not theoretically candidate to LAAC because of intracardiac thrombus. The prophylactic use of TCEP (including TG3) has been reported in a small retrospective study by Tarantini et al. and in some case series. Procedures were always successful and uneventful. Moreover, small captured debris on the device on visual examination proved its efficacy. The use of TCEP has been mentioned even by Beneduce et al. as a safer and more feasible strategy in AF patients. Conclusion Prophylactic use of TCEP during The Watchman Flex device implantation is safe and feasible.

This case describes a cardiac tamponade in systemic lupus erythematosus (SLE), an uncommon but life-threatening condition that needs prompt recognition. A 33-year-old woman with therapy-resistant SLE presented to the Emergency Department with chest pain and fever for 3 days. She was hemodynamically stable, the ECG showed signs of pericarditis and echocardiography showed a minimal pericardial effusion. Pericarditis was diagnosed and the patient was admitted to the Cardiology Ward. Seven hours later her symptoms deteriorated, presenting hemodynamic instability with hypotension and tachycardia. The ECG showed low QRS voltage and electrical alternans, echocardiography confirmed cardiac tamponade. The patient underwent an emergency pericardiocentesis with 220 mL of serous citrine liquid removed and immediate regression of symptoms. The cytology exam revealed inflammatory cells with no evidence of malignancy, blood culture and effusion fluid's tests came back negative. A Thoraco-abdominal CT revealed also bilateral pleural effusion (not present at the admission) and ascites. Signs, symptoms and medical history suggested SLE flare-up and high-dose oral glucocorticoid therapy was started. Our report highlights a rare presentation of life-threatening polyserositis in SLE flare-up. Although pericarditis and pericardial effusion are frequently-reported SLE's cardiovascular complications, rapid development of cardiac tamponade is far from common. Acute cardiac tamponade, like in our case, is an indication for emergency pericardial drainage to restore an adequate cardiac output. We describe an out of ordinary case of a patient in whom an accurate and timely diagnosis of SLE–related cardiac tamponade has been live–saving.

A 79 years–old male presented to our outpatient clinic with symptoms of an initial heart failure. He had an history of atrial fibrillation (AF), anaemia and thrombocytopaenia, which have never been deeply investigated, bilateral carpal tunnel syndrome. Electrocardiogram (EKG) showed AF with normal ventricular rate and low peripherical QRS voltages. Laboratory testing was significant for NT proBNPelevation, pancytopenia and iron overload. An echocardiogram (ECHO) was done showing a hypokinetic and dilated biventricular cardiopathy. The therapy was therefore optimized with clinical benefit. At coronary angiography a severe stenosis of left coronary artery was observed with normal myocardial perfusion imaging. Cardiovascular magnetic resonance (CMR) excluded an iron intramyocardial overload (in contrast to the hepatic and splenic parenchyma) and detected a subendocardial pattern of LGE at lateral and mid–basal septal area. Emochromatosis and Gaucher disease were excluded. As suggested by hematologists, he underwent osteomedullary biopsy (OMB) and a myelodysplastic syndrome (MDS) was diagnosed. He was still symptomatic for dyspnea on mild exertion. The following ECHO revealed normal left ventricular (LV) size with moderate concentric remodeling, mildly impaired LV systolic function and LV filling pattern suggestive of restrictive cardiomyopathy. All these data prompted suspicion for an infiltrative cardiopathy. Nuclear scintigraphy with the use of bone seeking agent was done and showed Perugini grade 2 cardiac uptake. Moreover, amyloid deposits were identified after Congo red–staining from OMB. immunoglobulin light chain (LA) amyloidosis was excluded. Conclusion based on the above findings, Cardiac Amyloidosis TTR–related wild type was diagnosed. The diagnosis of MDS and the identification of iron overload were incidental findings. The patient, currently in follow up at our center, is a candidate to Tafamidis.

On behalf of the Program Committee, a very warm welcome to the Seventh Italian Conference on Computational Linguistics (CLiC-it 2020). This edition of the conference is held in Bologna and organised by the University of Bologna. The CLiC-it conference series is an initiative of the Italian Association for Computational Linguistics (AILC) which, after six years of activity, has clearly established itself as the premier national forum for research and development in the fields of Computational Linguistics and Natural Language Processing, where leading researchers and practitioners from academia and industry meet to share their research results, experiences, and challenges.

The task of Dialogue Act (DA) tagging, a crucial component in many conversational agents, is often addressed assuming a single DA per speaker turn in the conversation. However, speakers’ turns are often multifunctional, that is they can contain more than one DA (i.e. “I’m Alex. Have we met before?” contains a ‘statement’, followed by a ‘question’). This work focuses on multifunctional DA tagging in Italian. First, we present iLISTEN2ISO, a novel resource with multifunctional DA annotation in Italian, created by annotating the iLISTEN corpus with the ISO standard. We provide an analysis of the corpus showing the importance of multifunctionality for DA tagging. Additionally, we train DA taggers for Italian on iLISTEN (achieving State of the Art results) and iLISTEN2ISO. Our findings indicate the importance of using a multifunctional approach for DA tagging.

The development of additive manufacturing techniques is allowing for the design of highly customised components with enhanced functionality in many application sectors. This paper describes the full aerothermal assessment of four novel hierarchically-layered fractal-like volumetric absorbers, designed to be employed in high temperature concentrating solar power applications. Absorbers are built by the lateral repetition of elementary cells on a 2D plane, which are arranged into constituent layers and stacked up following fractal growth patterns. They have been manufactured in stainless steel by selective laser melting. By fine tuning both the geometry of elementary cells and their growth patterns, the absorber porosity distribution can be tailored on a per-layer basis. This leads to optimised aft-shifted radiation absorption profiles and allows for the introduction of intricate convective heat transfer augmentation features. Experimental temperature measurements are presented which demonstrate that these variable porosity absorbers are able to generate and exploit volumetric effects, an advancement with respect to both monolithic honeycombs and isotropic foams. Solar-to-thermal conversion efficiencies, however, are shown to be of the same order as in those other receiver geometries. It is argued that the main reasons for this lie in the use of stainless steel, a material of relatively high reflectivity, and the predominantly low convective heat transfer rates found in the laminar flows established in these components.

We describe a compact fiber-optic probe (2 mm outside diameter) that utilizes spatially-resolved diffuse reflectance for tissue optical property recovery. Validation was performed in phantoms containing Intralipid 20% as scatterer, and methylene blue (MB), MnTPPS, and/or India ink as absorbers. Over a range of conditions, the reduced scattering coefficient was recovered with a root mean square error (RMSE) of 0.86-2.7 cm-1 (average error = 3.8%). MB concentration was recovered with RMSE = 0.26-0.52 µM (average error = 15.0%), which did not vary with inclusion of MnTPPS (p=0.65). This system will be utilized to determine optical properties in human abscesses, in order to generate treatment plans for photodynamic therapy.