A new modified ion-selective electrode with membranes of LaF3 single crystals with different internal contacts (solid steel or electrolyte) and with FexOy nanoparticles as loading was developed. The best response characteristic with linear potential change was found in the fluoride concentration range from 10−1 to 3.98 × 10−7 M. The detection limit for the electrolyte contact was determined at 7.41 × 10−8 M with a regression coefficient of 0.9932, while the regression coefficient for the solid contact was 0.9969. The potential change per concentration decade ranged from 50.3 to 62.4 mV, depending on whether the contact was solid or electrolytic. The prepared modified electrode has a long lifetime, as well as the possibility of application in different positions (solid contact), and it can also be used for the determination of iron ions. The electrode characterization was performed with scanning electron microscopy and elemental analysis with the technique of electron-dispersive X-ray spectroscopy.

The low environmental impact and high long-term performance of products are becoming imperative for the sustainable development of the construction industry. Alkali-activated materials (AAMs) are one of the available low-embodied-carbon alternatives to Portland cement (OPC). For their application in the marine environment or where de-icing salts are used, it is of utmost importance to demonstrate their equal or better performance compared to OPC. The aim of this study was to compare the corrosion behaviour of the steel in AAMs based on different regionally available by-products with the behaviour of the steel in OPC. The by-products used were fly ash, slag, silica fume, and iron-silica fines. The corrosion process of each system was monitored by the corrosion potential and polarisation resistance during exposure to tap water and chloride solution over a period of almost one year. Certain AAMs showed a higher resistance to chloride penetration compared to OPC, which was attributed to the smaller number of capillary pores and higher gel phase precipitation. The same corrosion resistance compared to OPC was achieved with alkali-activated fly ash and alkali-activated slag mortars. The stability of the systems in tap water and chloride solution was confirmed by the visual assessment of the steel surface at the end of the test period.

High-sensitive cardiac Troponin T (hsTnT) is the most frequently used biomarker for the detection of cardiomyocyte injury. Severe aortic stenosis (AS) leads to an increased left ventricular load, with the potential of myocardial injury reflected by increased TnT levels. However, there is a lack of studies showing the prevalence and prognostic role of elevated hsTnT in patients with asymptomatic AS. To examine the association between the hsTnT levels and AS severity in asymptomatic AS patients. We hypothesized that patients with more severe AS will have elevated hsTnT levels and that hsTnT levels are associated with a higher risk for aortic valve events (AVE) and all-cause mortality (ACM). We performed a post-hoc analysis in 1739 asymptomatic patients with mild to moderate-severe AS, enrolled in the randomized, double-blinded SEAS-study (Simvastatin and Ezetimibe in Aortic Stenosis). All patients had available hsTnT blood samples measured at baseline (Year 0) and Year 1. We defined moderate to severe (mod-severe) AS as a transaortic maximal outflow velocity (Vmax)>3.5 m/s combined with aortic valve area (AVA)<1.0 cm2, otherwise non-severe AS. An hsTnT>14 ng/L was high according to assay (Roche, Elecsys Troponin T hs on cobas e 601). Linear multivariable regression model examined the association of hsTnT levels to clinical and echocardiographic variables. Cox multivariable regression model evaluated competing risks and hazard ratios (HR) of outcomes while adjusting for relevant variables, including a Framingham 10-years risk score of cardiovascular diseases. The competing risks were either ACM or AVE, i.e. the first of AVR, cardiovascular death and heart failure due to AS progression. At baseline, hsTnT was high in 26% (453/1739) patients; 25% (380/1529) in non-severe and 35% (73/210) in mod-severe AS. Relative TnT change over one year was 17% (mean 1.17, SD 1.01); 15% in non-severe vs. 32% in mod-severe AS, and neither associated to AS severity, hsTnT at baseline or lipid-lowering treatment. In multivariable linear regression analysis, there were significant correlations between hsTnT at baseline and age, male gender, creatinine, left ventricular mass index and BMI (all p<0.001, R-square=0.42), but not with AS severity. In multivariable Cox regression analyses, a high hsTnT at baseline was associated with AVE 1.61 [95% CI 1.29–1.99]. In contrast, hsTnT at baseline was not associated to all-cause mortality (see figure). In asymptomatic AS patients without severe AS, high-sensitive Troponin T is not associated with AS severity in cross-sectional analyses, and its levels do not change substantially during one year of follow-up. However, patients with hsTnT >14 ng/l had a sixty percent higher independent risk of subsequent aortic valve events. Multivariable Cox regression Type of funding source: Private company. Main funding source(s): Acknowledgements: Main sponsor (SEAS): MSD Singapore Company, LLC, partnership between Merck & Co. Inc. and Schering-Plough Corporation. Blood analysis sponsor: Roche

Coronary chronic total occlusion (CTO) is characterized by the presence of collateral blood vessels which can provide additional blood supply to CTO-artery dependent myocardium. Successful CTO recanalization is followed by significant decrease in collateral donor artery blood flow and collateral derecruitment. Study aim was to assess time-dependent changes in coronary flow reserve (CFR) in collateral donor artery after CTO recanalization and identify factors that influence these changes. Our study enrolled 31 patients with CTO scheduled for percutaneous coronary intervention (PCI). Non-invasive CFR was measured before PCI in collateral donor artery, and 24h and 6 months post-PCI in CTO and collateral donor artery. Gated SPECT MIBI was performed before PCI, while quality of life was assessed by Seattle angina questionnaire (SAQ) pre-PCI, and 6 months after PCI. Collateral donor artery showed significant increase in CFR 24h after CTO recanalization compared to pre-PCI values (2.30±0.49 vs. 2.71±0.45, p=0.005), which remained unchanged after 6 months (2.68±0.24). Maximum baseline blood flow velocity of the collateral donor artery showed significant decrease measured 24h post-PCI compared to pre-PCI values (0.28±0.06 vs. 0.24±0.04m/s), and remained similar after 6-months. There was no significant difference in maximum hyperemic blood flow velocity pre-PCI, 24h and 6 months post-PCI. CFR change of the collateral donor artery 24h post-PCI compared to pre-PCI values showed inverse correlation with left ventricle ejection fraction (LVEF) measured on SPECT. CFR changes showed no correlation with the changes in quality of life assessed by SAQ post-PCI compared to pre-PCI. Significant increase in CFR of the collateral donor artery was observed within 24h after successful recanalization of CTO artery, which maintained constant after the 6 months follow-up. This increase was largely driven by the significant reduction in the maximum baseline blood flow velocity within 24h after CTO recanalization compared to pre-PCI values. Our results suggest that possible benefit of CTO recanalization could be the improvement in physiology of the collateral donor artery. Type of funding source: None

Background There is currently no evidence suggesting that COVID-19 takes a different course in HIV-positive patients on antiretroviral treatment compared to the general population. However, little is known about the relation between specific HIV-related factors and the severity of the COVID-19 disease. Methods We performed a retrospective analysis of cases collected through an on-line survey distributed by the Euroguidelines in Central and Eastern Europe Network Group. In statistical analyses characteristics of HIV-positive patients asymptomatic/moderate and moderate/severe course were compared. Results In total 34 HIV-positive patients diagnosed with COVID-19 were reported by 12 countries (Estonia, Czech Republic, Lithuania, Albania, Belarus, Romania, Serbia, Bosnia and Herzegovina, Poland, Russia, Hungary, Bulgaria). Asymptomatic courses of COVID-19 were reported in four (12%) cases, 11 (32%) patients presented with mild disease not requiring hospitalization, moderate disease with respiratory and/or systemic symptoms was observed in 14 (41%) cases, and severe disease with respiratory failure was found in five (15%) patients. The HIV-related characteristics of patients with asymptomatic/mild course of COVID-19 were comparable to those with moderate/severe course of COVID-19, except for the use of non-nucleoside reverse transcriptase inhibitors (NNRTIs) in cART regimen ( 0.0% vs. 31.6% respectively, p = 0.0239 ). Conclusions In our analyses HIV viral suppression and immunological status were not associated with the course of COVID-19 disease. On the contrary the cART regimen could contribute to severity of SARS-CoV-2 infection. Large and prospective studies are necessary to further investigate this relations.

746 EJD, vol. 30, n◦ 6, November-December 2020 7. Hayami M, Fuzitani T. A case of benigh lymphocytoma found in the stroma of Bowen’s disease. Rinsho hihuka 1998; 52: 1130-3. 8. Vandaele R. Benign lymphocytoma (lymphadenoma) of the skin associated with Bowen’s disease. Arch Belg Dermatol Syphiligr 1957; 13: 494-9. 9. Maubec E, Pinquier L, Viguier M, et al. Vaccination-induced cutaneous pseudolymphoma. J Am Acad Dermatol 2005; 52: 623-9.

Controversies exist how to predict medium term mortality (Mt) in diabetics (DM) with 3 vessel (3VD) and/or left main (LM) disease undergoing myocardial revascularization ranging from Syntax Score II (SSII) where DM was not predicative variable up to FREEDOM formula which was derived, just from population with DM (without LM), having DM patients (Pts) requirement of insulin as one of predicative variable. To compare predicative power of SSII, FREEDOM and formula developed in our institution in Pts post first isolated CABG with 3VD and/or LM with DM. From our prospective data base of 2455 consecutive pts who had the first isolated CABG in the period 01/2012–12/2014 with complex Ischemic Heart Disease with 100% follow up of 4 years all-cause Mt we created by random sampling Training (1321; Mt:10.4%; DM 511; Mt:13.3%) and Validation (1134; Mt:10.0%; DM 414; Mt: 11.8%) sets. After deriving predicative formula (Cox regression) from training population we validated FREEDOM, SSII and Our Formula in 414 pts with DM from the Validation set. Characteristics of pts, our formula, predicating power by C Statistics, Calibration plots and Brier scores are presented in Picture 1. FREEDOM formula designed just for DM pts with complex Ischemic Heart Disease without LM had the smallest standard error in the estimate, but moderate C statistics as Syntax Score II and our formula which may be used for pts with and without DM and 3VD and/or LM. Picture 1 Type of funding source: Public grant(s) – National budget only. Main funding source(s): Ministry of education, science and technology development, Republic of Serbia

Freedom formula (FF) was derived very recently to assist in decision making by Heart Team in patients (Pts) with diabetes (DM) who are in need for myocardial revascularization (Percutaneous Coronary Intervention or Coronary artery bypass grafting (CABG)) due to complex ischemic Heart disease (but without left main steam disease (LM)). In external validation moderate C statistics values were obtained. To validate FF predictive value in Pts with DM and more complex patients (three vessel (3VD) and/or LM as well lower left ventricular ejection fraction (LVEF)) than in FREEDOM population. From our prospective data base of 2455 consecutive pts who had the first isolated CABG in the period 01/2012–12/2014 with 3VD and/or LM with 100% follow up of 4 years All-cause Mortality (Mt) we retrieved 925 pts with DM. DM was present in 925 Pts (Mt: 12.6%). On insulin were 318 (34.3%; Mt 14.5%). We analysed the predicative value of FF in the whole group (925) of pts with DM as well as in subgroups with LM (294) and without LM (631; most similar to original Freedom population), separately. Characteristics of pts, Freedom formula, predicating power by C Statistics, Calibration plots and Brier scores are presented in Picture 1. Our external validation of FF was almost identical as previous published one. Furthermore, the FF may be of value even in pts with LM disease and other vessels involved. Of note our pts as seen by combined LVEF, ClCr and LM were sicker than pts in FREEDOM. Picture 1 Type of funding source: Public grant(s) – National budget only. Main funding source(s): Ministry of education, science and technological development, Republic of Serbia

Two-dimensional (2-D) volumetric exercise stress echocardiography (ESE) provides an integrated view of preload reserve through end-diastolic volume (EDV) and left ventricular contractile reserve (LVCR) through end-systolic volume (ESV) changes. To assess the dependence of stroke volume (SV) and cardiac output (CO) upon LVCR EDV changes and heart rate (HR) during ESE. We prospectively performed semi-supine bicycle or treadmill ESE in 1,344 patients (age 59.8±11.4 years; 550 female; ejection fraction = 62.5±8%) referred for known or suspected coronary artery disease in 20 quality controlled laboratories of 16 countries from 2016 to 2019. SV was calculated at rest and peak stress from raw measurement of LV EDV and ESV by biplane Simpson rule, 2-D echo. LVCR was the stress-rest ratio of force (systolic blood pressure by cuff sphygmomanometer/ESV, abnormal values <2.0 identify a “weak” heart). Preload reserve was defined by an increase in LV EDV. Abnormal values (lack of EDV increase, peak EDV ≤ rest EDV) identify a “stiff” heart. Cardiac output was calculated as SV * HR (measured with standard EKG). HR reserve (stress/rest ratio) <1.85 identifies a “slow” heart with chronotropic incompetence. By selection, all patients had negative SE by wall motion criteria. Of the 1,344 patients included in the study, 448 belonged to the lowest tertile of CO increase. Of them 326 (73%) achieved HR reserve <1.85; 220 (49%) had a blunted LVCR and 374 (83%) a reduction of preload reserve, with 348 patients (78%) showing ≥2 abnormalities. The more the abnormal criteria, the worse the CO response, which was lowest in slow, stiff and weak hearts: see figure. Patients with normal CO reserve during exercise usually have a fast, compliant and strong heart. Abnormal CO reserve is associated with heterogeneous hemodynamic responses, with slow, stiff and/or weak hearts. The clarification of underlying hemodynamic heterogeneity is the prerequisite for a personalized treatment, and can be easily extracted from a standard 2-D volumetric SE. Hearts with normal CO are all alike; every heart with abnormal CO is abnormal in its own way. CO % changes in subsets (*p<0.001) Type of funding source: None

The role of autonomous cooperative vehicles will undoubtedly be important in Intelligent Transportation Systems (ITS) to increase both the safety and the overall efficiency of a high traffic network system. An autonomous platooning provides one promising strategy for decreasing total fuel consumption of a fleet of vehicles and potential risk of accidents, especially during long-distance transportation. In this work, we provide a proof-of-concept for a simulation framework in which it is possible to simulate platoon and other multi-vehicle systems using realistic vehicle models within different traffic scenarios, which is based on ROS, Gazebo and SUMO. The framework enables an easy-to-use perception and control modules of the autonomous driving stack for a realistic vehicle models, while preserving a convenient setup of different high traffic platooning scenarios. Consequently, it provides a platooning design step for conducting reliable development analyses and a platform for comparisons of different platooning strategies. We illustrate the effectiveness of the proposed platooning framework through three typical scenarios using a distributed model predictive control scheme with a platoon consisted of Toyota Prius car models.