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We discuss how to optimize deployment of optical amplifiers (inline, booster and pre-amplifiers), in realistic metro networks with the objective of minimizing their cost while ensuring the Quality-of-Transmission of all lightpaths.

Reduced order modeling (ROM) techniques are numerical methods that approximate the solution of parametric partial differential equation (PDE) by properly combining the high-fidelity solutions of the problem obtained for several configurations, i.e. for several properly chosen values of the physical/geometrical parameters characterizing the problem. In this contribution, we propose an efficient non-intrusive data-driven framework involving ROM techniques in computational fluid dynamics (CFD) for hemodynamics applications. By starting from a database of high-fidelity solutions related to a certain values of the parameters, we apply the proper orthogonal decomposition with interpolation (PODI) and then reconstruct the variables of interest for new values of the parameters, i.e. different values from the ones included in the database. Furthermore, we present a preliminary web application through which one can run the ROM with a very user-friendly approach, without the need of having expertise in the numerical analysis and scientific computing field. The case study we have chosen to test the efficiency of our algorithm is represented by the aortic blood flow pattern in presence of a Left Ventricular Assist Device (LVAD) when varying the pump flow rate., Comment: arXiv admin note: substantial text overlap with arXiv:2007.03527

OBJECTIVE: The aim of this study was to assess clinical and hemodynamic outcomes of transapical aortic valve implantation (TA-TAVI) in patients enrolled in the Italian Registry of Trans-Apical Aortic Valve Implantation (I-TA). METHODS: From April 2008 until November 2010, 504 patients from 20 Italian centers were enrolled in the I-TA registry. Mean logistic EuroSCORE and Society of Thoracic Surgeons score were 24% ± 16% and 11% ± 4%, respectively. Mean follow-up was 9.2 ± 6.5 months (range, 1-26 months). Outcomes were analyzed according to intraoperative complications, procedural volume (high-volume centers, >20 cases; low-volume centers, < 20 cases) and learning curve (first 50% cases vs second 50% cases of each center). RESULTS: All-cause overall mortality was 8.3% (42 patients). Device success was 99% (500/504 patients). Intraoperative severe complications occurred in 24 (4.8%) patients. Overall 2-year survival was 71.5% ± 6.2%. At discharge, peak and mean gradients were 16.4 ± 11.2 and 8.7 ± 4.1 mm Hg, respectively, and effective orifice area was 1.67 cm(2). These values remained stable at 3, 6, and 12 months after surgery. Independent risk factors for mortality after TA-TAVI were as follows: New York Heart Association class III and IV (odds ratio [OR], 4.43; 95% confidence intervals [CI], 1.28-15.40; P = .02); logistic EuroSCORE greater than 20 (OR, 1.83; 95% CI, 1.02-3.29; P = .04); creatinine concentration greater than 200 μmol/L (OR, 2.56; 95% CI, 1.07-6.15; P = .03), and intraoperative complications (OR, 5.80; 95% CI, 2.68-12.55; P < .001). There were no significant differences in outcomes between high- and low-volume centers and between the first and the second 50% of cases. CONCLUSIONS: TA-TAVI represents a safe and effective alternative treatment for patients who are inoperable or at high risk for surgery. The occurrence of an intraoperative complication significantly affects survival. Procedural volume and learning curve have no impact on patient survival.

The role of heterotopic heart transplantation in coronary heart disease has not been defined. Between 1983 and 1988, 28 patients with end-stage ischemic heart disease were managed by heterotopic heart transplantation and adjunctive operation on the recipient heart: coronary artery bypass grafts and aneurysmectomy, 20; coronary artery bypass grafts, 5; and aneurysmectomy, 3. Indications were feasibility of operative procedures to the recipient heart and small donor size (61% of the donors were less than 15 years). The 1-year and 5-year actuarial survival was 79% and 63%. Of the 22 patients who survived to 2-year follow-up, all of whom had been severely limited (New York Heart Association grade III/IV) preoperatively, 20 were in grades I or II at 2-year follow-up (p less than 0.001). In 14 of 22 patients (64%), the recipient heart augmented the donor cardiac output substantially, and in 4 the recipient heart supported the patient when the donor heart failed to eject. In conclusion, this series demonstrates the efficacy of heterotopic transplantation combined with operation to the recipient heart in the management of patients with end-stage ischemic heart disease.

Single photon detection is one of the most challenging goals of photonics. In recent years, the study of ultra-fast and/or low-intensity phenomena has received renewed attention from the academic and industrial communities. Intense research activity has been focused on bio-imaging applications, bio-luminescence, bio-scattering methods, and, more in general, on several applications requiring high speed operation and high timing resolution. In this paper we present design and characterization of bi-dimensional arrays of a next generation of single photon avalanche diodes (SPADs). Single photon sensitivity, dark noise, afterpulsing and timing resolution of the single SPAD have been examined in several experimental conditions. Moreover, the effects arising from their integration and the read-out mode have also been deeply investigated.

In the last years the single-photon detection with silicon devices has become an important goal. Here we present the performance of a new generation of single-photon avalanche diodes manufactured by ST-Microelectronics. The 5 x 5 array configuration has been also realized and the performances, in terms of crosstalk and common readout mode, have been investigated.

Following our previous work which has led us to fabricate single pixels of geiger mode avalanche photodiodes (GMAPs), we present in this letter the results regarding the fabrication and characterization of a bidimensional array of GMAPs. Low dark count rates and very good uniformity over the sensor are reported. High quantum efficiency in the visible range has been measured. Measurements indicate that not all the nominal active area is effectively sensitive. We have some preliminary evidence that no crosstalk effects are present in our device. Notwithstanding this, in view of a near future shrinking of all dead regions, an optical trench process has been developed and is illustrated here. Possible future trends are highlighted.

A technique for correction of interrupted aortic arch during heart-lung transplantation is described. This operation was performed in a 14-year-old patient with situs solitus, absent right atrioventricular connection, large atrial septal defect, ventricular septal defect, transposition of the great arteries, type B interrupted aortic arch, and severe pulmonary hypertension. The postoperative course was uneventful. Clinical, radiologic, and nuclear magnetic resonance investigation have shown evidence of good correction of the aortic arch anomaly. We concluded that donor tissue available during heart-lung transplantation is useful in correcting extracardiac anomalies.

In order to identify factors affecting early mortality in patients undergoing CABG for unstable angina, several risk factors have been analysed in a group of 120 patients. Systemic hypertension and left ventricular impairment were shown to be significant risk factors (Systemic hypertension, P less than 0.01; EF less than or equal to 0.35, P less than 0.01; LVEDP greater than or equal to 20 mmHg, P less than 0.025). Overall mortality rate was 5% (6/120). No influence could be recognized for age, sex, previous MI, emergency surgery, extension of coronary disease, completeness of revascularization and mode of onset of symptoms.

We briefly describe a project which aims at proving that single-photon sensing can be made accessible in form of low-cost off-the-shelf micro-devices with micro-optical/micro-mechanical coupling systems. In order to achieve this challenging goal, we are making use of two different micro-technologies, not yet fully established but promising and innovative in and of themselves. We then plan to combine them into a more challenging micro-technology, capable of bringing the single-photon handling to the shelf

The results of experimental research on ultraweak photon emission carried out at the Institute of Physics, Catania University, are presented here. A correlation has been demonstrated to exist between photon emission and growth activity in the germination of soya seeds and also during the exponential phase of the growth of yeast cell cultures. In addition an experiment on the self irradiation of yeast cells is reported that confirms the mitogenic effect hypothesized by Gurwitsch.

Background: To assess early and late mortality in patients with isolated acute tricuspid valve infective endocarditis (TVIE) using data from a multicenter registry.Methods: From 1983 to 2018, isolated acute TVIE was surgically treated in 157 (3.8%) patients [mean age 47 +/- 16 years (range 15-86 years), 25% females]. Of these, 142 (90%) had native tricuspid regurgitation, 7 (5%) native tricuspid valve (TV) steno-regurgitation, and 8 (5%) prosthetic TVIE. Intravenous drug use (IVDU) was recorded in 38% of patients, infection involved cardiac implantable electronic device leads in 21%, and vascular catheters for dialysis in 1%; in the remaining cases, the cause was unknown. The primary endpoint was in-hospital outcome, long-term freedom from recurrence and overall survival.Results: Overall, 77 (49%) patients underwent TV repair, 72 (46%) TV replacement, and 8 (5%) prosthetic TV replacement. Early mortality was 11% (n = 17). Expected early mortality according to EndoSCORE was 12%, with age (odds ratio 1.06) and redo (odds ratio 6.64) as risk factors. Late deaths occurred in 31 patients and TVIE recurrences in 4. Survival rates at 10, 20, and 25 years were 66%, 60%, and 44%, respectively. Risk factors were age [hazard ratio (HR) 1.06], mycotic TVIE (HR 4.2), IVDU (HR 4.90), infected prosthesis replacement (HR 4.4), and presence of cardiac implantable electronic device leads (HR 3.0). No significant difference was found in valve repair vs. replacement and in IVDUs vs. non-IVDUs.Conclusions: Patients with isolated acute TVIE undergoing surgical treatment show acceptable early and late outcomes. TVIE recurrence was low, and repair of the affected valve does not seem to confer any advantage either at early or long term up to 25 years. (C) 2019 Elsevier B.V. All rights reserved.

In the framework of the research project ETHICS "Pre-clinical experimental and theoretical studies to improve treatment and protection by charged particles" funded by the National Nuclear Physics Institute, Italy, we studied the phenomenon called delayed luminescence emitted by non-tumorigenic breast epithelial MCF10A cell line after proton irradiation at different doses (0.5, 2, 6, 9 Gy). The aim is to found possible correlations between delayed luminescence and in vitro damaging induced by ion irradiation. The first results of this research show that the delayed luminescence kinetics is proton dose dependent. An interesting correlation between delayed luminescence and clonogenic potential was observed.

Summary The antiplatelet agent ticagrelor has recently been found to have bactericidal activity, demonstrated in vitro and in an in vivo mouse model, which warrants further clinical investigations. The aim of this study was to evaluate infectious complications after coronary artery bypass grafting in patients pre-operatively treated with ticagrelor or clopidogrel. In a multi-centre trial, all adult patients who were pre-operatively treated with ticagrelor or clopidogrel prior to isolated primary coronary artery bypass grafting were eligible. Propensity score matching was used. Outcome measures were any sternal wound infection, deep sternal wound infection, and any in-hospital use of postoperative antibiotics. Of 2311 patients who were included, 1293 (55.9%) received clopidogrel and 1018 (44.1%) ticagrelor pre-operatively. In both overall and propensity score matched analyses, ticagrelor was associated with a similar incidence of infectious complications compared to clopidogrel. Our findings do not support a clinically relevant bactericidal effect of ticagrelor in patients undergoing coronary artery bypass grafting.

Objectives: A history of percutaneous coronary intervention increases the risk of death and complications of coronary artery bypass grafting. This retrospective multicenter study evaluated the impact of continuative use of statin on postoperative outcomes when subsequent elective coronary artery bypass grafting is required after percutaneous coronary intervention. Methods: Among 14,575 patients who underwent isolated first-time coronary artery bypass grafting between January 2000 and December 2010, 2501 who had previous percutaneous coronary intervention with stenting and fulfilled inclusion criteria were enrolled. Continuative statin therapy was used in 1528 patients and not used in 973 patients. Logistic multiple regression and propensity score analyses were used to assess the risk-adjusted impact of statin therapy on in-hospital mortality and major adverse cardiac events. The Cox proportional hazards model was constructed to assess the effect of continuative statin therapy on 24-month outcome. Results: At multivariate analysis, age more than 70 years, 3-vessel or 2-vessel plus left main coronary disease, multivessel percutaneous coronary intervention, ejection fraction 0.40 or less, diabetes mellitus, and logistic European System for Cardiac Operative Risk Evaluation 5 or greater were independent predictors of hospital mortality and major adverse cardiac events. After propensity score matching, conditional logistic regression analysis demonstrated that continuative statin therapy before coronary artery bypass grafting reduced the risk for hospital and 2-year mortality (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.12-0. 57; P ¼ .004 and OR, 0.6; 95% CI, 0.36-0.96; P ¼ .04, respectively) and major adverse cardiac events (OR, 0.31; 95% CI, 0.18-0.78; P ¼ .003 and OR, 0.5; 95% CI, 0.34-0.76; P ¼ .006, respectively). Conclusions: Long-term statin treatment after percutaneous coronary intervention improves early and midterm outcome when surgical revascularization will be required. (J Thorac Cardiovasc Surg 2014;148(5):1876-8)

Objectives: Patient selection is crucial to achieve good outcomes and to avoid futile procedures in patients undergoing transcatheter aortic valve replacement. The aim of this multicenter retrospective study was to identify independent predictors of 1-year mortality in patients surviving after transapical transcatheter aortic valve replacement. Methods: We analyzed data from the Italian registry of transapical transcatheter aortic valve replacement that includes patients undergoing operation in 21 centers from 2007 to 2012. Futility was defined as mortality within 1 year after transapical transcatheter aortic valve replacement in patients surviving at 30 days. Thirty-day survivors were divided in 2 groups: futility (group F) and nonfutility (group NF). Cox proportional hazard regression analysis was performed to identify independent predictors of futility. Results: We analyzed data from 645 patients with survival of 30 days or more after transapical transcatheter aortic valve replacement. Groups F and NF included 60 patients (10.8%) and 585 patients (89.2%), respectively. Patients in group F were more likely to have insulin-dependent diabetes (15% vs 7.2%, P = .03), creatinine 2.0 mg/dL or greater or dialysis (18.3% vs 8.2%, P = .01), logistic European System for Cardiac Operative Risk Evaluation greater than 20% (66.7% vs 50.3%, P = .02), preoperative rhythm disorders (40% vs 25.3%, P = .03), critical preoperative state (8.3% vs 1.8%, P = .002), and left ventricular ejection fraction less than 30% (15% vs 2.9%, P < .001). The multivariate analysis identified the following as independent predictors of futility: insulin-dependent diabetes (odds ratio, 3.1; P = .003), creatinine 2.0 mg/dL or greater or dialysis (odds ratio, 2.52; P - .012), preoperative rhythm disorders (odds ratio, 1.88; P - .04), and left ventricular ejection fraction less than 30% (odds ratio, 4.34; P = .001). Conclusions: According to our data, among patients undergoing transapical transcatheter aortic valve replacement, those with insulin-dependent diabetes, advanced chronic kidney disease, rhythm disorders, and low left ventricular ejection fraction have a higher risk to undergo futile procedures.

Background Severe prosthesis-patient mismatch (PPM) is considered to further decrease survival compared to moderate PPM. This study aimed to assess the impact of severe PPM on survival after aortic valve replacement (AVR). Methods We retrospectively studied 2404 consecutive patients with PPM who underwent first-time AVR for pure stenosis between January 2003 and December 2014. Mismatch was moderate for indexed effective valve orifice >0.65 to 220 g/m2 and concomitant coronary artery revascularization. After propensity score matching, conditional logistic regression analysis demonstrated no relationship between severe mismatch and increased mortality at 5 postoperative years (HR, 0.9; 95% CI, 0.7–1.6; p = 0.06), whereas it was significant at 10 postoperative years (HR, 1.9; 95% CI, 1.2–2.5; p = 0.03). During the follow-up, severe mismatch was associated with more frequent hospital readmissions for cardiac events (0.12 vs. 0.08 events/patient/year, p = 0.007). Conclusions Patients with severe mismatch had lower long-term survival and higher incidence of hospital readmissions for cardiac events. However, the effect of severe mismatch on outcome appeared mainly related to the preoperative risk profile of each patient. © 2016 Japanese College of Cardiology

This multicenter study investigated the impact of previous percutaneous coronary interventions (PCI) on postoperative outcome and 5-year survival of subsequent coronary artery bypass grafting.Among 7,855 patients who underwent isolated first-time coronary artery bypass grafting between January 2000 and December 2005, 6,834 (87%) had no previous PCI and 1,021 (13%) had previous PCI with stenting. Logistic multiple regression and propensity score analyses were used to assess the risk-adjusted impact of prior PCI on in-hospital mortality and major adverse cardiac events. The Cox regression model was used to assess the effect of prior PCI on 3-year and 5-year survival.After risk-adjusted multivariate analysis, age over 70 years, female sex, 3-vessel or 2-vessel plus left main coronary disease, multivessel PCI, ejection fraction 0.40 or less, diabetes mellitus, previous myocardial infarction, and chronic obstructive pulmonary disease were identified as independent predictors of both hospital mortality and major adverse cardiac events. After propensity score matching, conditional logistic regression analysis identified history of previous PCI as significantly associated with an increased risk for hospital mortality (odds ratio, 2.8; 95% confidence interval 1.4 to 4.8; p=0.003) and major adverse cardiac events (odds ratio 2.1; 95% confidence interval 1.2 to 3.6; p0.001). Survival at 3 and 5 years was lower in patients with previous PCI compared with the no-PCI patients (97.4%±0.01% vs 96.5%±0.02% and 94.2%±0.03% vs 92.1%±0.05%; log-rank test: p=0.03).Our results provided further evidence that history of PCI before coronary artery bypass grafting increases risk of both operative death and perioperative complications, and decreases survival at 5 years follow-up.

Background Prophylactic intraaortic balloon pump (IABP) support showed better outcomes in critical patients undergoing coronary revascularization compared with intraoperative or postoperative insertion. We conducted a prospective, randomized study to determine the optimal timing for preoperative IABP insertion in high-risk patients undergoing off-pump coronary artery revascularization. Methods The study enrolled 230 consecutive high-risk patients (having a logistic European System for Cardiac Operative Risk Evaluation score of ≥10) undergoing off-pump coronary artery revascularization. They were randomized for preoperative IABP starting at 2 hours (2T, n=115) or 12 hours (12T, n=115). Clinical, biochemical, and hemodynamic results, and the need for inotropic drug support, were markers of outcome and compared between groups. Results Hospital mortality in group 12T was reduced by 60%, but the difference between groups was not statistically significant (hazard ratio, 0.4; 95% confidence interval, 0.1 to 1.5; p = 0.1). Twelve hours of preoperative IABP therapy reduced postoperative low output syndrome (hazard ratio, 0.4; 95% confidence interval, 0.1 to 0.9; p = 0.03) and biomarker leakage upper normal limit (hazard ratio, 0.3; 95% confidence interval, 0.1 to 0.7; p = 0.001). Postoperative left ventricular function was similar between the groups. Group 2T patients required higher inotropic support for a longer average duration and prolonged postoperative intensive care unit and hospital length of stay. Conclusions Twelve hours preoperative IABP therapy improved treatment efficacy. Postoperative morbidity was reduced, but hospital mortality rate was not affected. The IABP-related complication rate was low and not related to the length of treatment.

Many recent studies on water have conjectured a complex structure composed of hydrogen bonded low- and high-density domains. In this work the structure of pure water and aqueous solutions of silica gel (TEOS) has been investigated by using delayed luminescence, which previously have showed significant increase in aqueous salt solutions where low-density domain formation is expected. Photon emission shows an Arrhenius trend with an activation energy in water-TEOS solutions larger than in pure water and salt-water solutions. Moreover, delayed photon emission decay shows an intrinsic lifetime of about 5 microseconds both in solutions and in pure water that, along with secondary lifetimes induced by the presence of TEOS, could be related to the formation of different domains., 15 pages, 8 figures, 1 table