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The turning process of the duplex stainless steel (DSS) has received special attention in recent years due to its attractive combination of mechanical and corrosion properties, which are suitable for many marine and petrochemical applications, particularly where chlorides are present. Thus, a better understanding of the machining parameters is critical in attaining high quality in the turning process of the DSS. This paper presents a predictive and optimization model based on integrated response surface methodology (RSM) and desirability function to predict the surface roughness, the material removal rate, and the corresponding machining parameters during the turning of the UNS S32760 with a chemical vapor deposition (CVD) tool. The experimental design was a central composite design (CCD) with three center points and an axial distance of 1.68 from the center. The statistical significance of the developed model has been tested by the analysis of variance and the influence of the factors analyzed. The optimization results are presented considering three aims: (1) minimizing surface roughness; (2) maximizing the material removal rate; and (3) minimizing the surface roughness and maximizing the material removal rate.

Introduction The coronary sinus Reducer device (CSRD) emerged as a complementary therapy in patients with severe angina refractory to optimal medical therapy and not amenable to revascularization. Our aim was to assess the safety and efficacy of the CSRD in a real-world setting. Methods Twenty-six patients with refractory angina (RA), evidence of myocardial ischemia attributable to the left coronary artery unsuitable for revascularization were treated with the CSRD at two centres between May 2017 and July 2019. Safety endpoints were procedural success and complications. Efficacy endpoints, assessed at 6-month follow-up, were a reduction in CCS class, improvement in quality of life (QoL) assessed using the short version of the Seattle Angina Questionnaire (SAQ-7) and reduction in anti-anginal therapy. Results Twenty-three patients had end-stage CAD without revascularization targets and 3 patients had microvascular disease without epicardial stenosis. Procedural success was achieved 23 patients, with 2 device/procedural-related complications and one anatomically-related failure to deliver the device. Ultimately 25 patients implanted the device and entered the efficacy analysis. Eighteen patients (75.0%) had at least 1 reduction in CCS class, 41.7% had at least 2 class reductions, and 16.7% became asymptomatic, with a mean reduction of CCS class of 1.3±0.2 (p=0.001) at 6-month follow-up. All SAQ-7 domains improved, namely physical limitation (p=0.001), angina frequency (p=0.005) and QoL (p=0.006). There was a mean reduction of anti-ischemic drugs from 3.4±1.1 to 2.9±1.2 (p=0.010). Conclusion In this real-world, multicentric experience, implantation of the CSRD was associated with improvement of angina and QoL in patients with RA. Funding Acknowledgement Type of funding sources: None.

Background and aim Standard single antiplatelet regimen (SAPT) is currently recommended before invasive risk stratification in non-ST elevation acute coronary syndromes (NSTE-ACS). However, there are subsets in whom dual antiplatelet therapy (DAPT) may be more protective according to the coronary anatomy and revascularization strategy. We aimed to identify pre-procedural predictors of coronary artery complexity that may be helpful in selecting an individualized antiplatelet regimen. Methodology Retrospective single-center study including patients with NSTE-ACS performing coronary angiography between January 2020 and July 2021. Clinical variables and classical NSTE-ACS risk scores (TIMI, GRACE and HEART) were captured and SYNTAX 1 score was calculated. Patients were divided into low (0–22), moderate (23–32) and high (≥33) SYNTAX score. Multivariate logistic regression analysis was performed to determine predictors of anatomical complexity (defined as significant left main disease [stenosis ≥50%] or SYNTAX ≥33). Results A total of 448 patients were included (mean age 67±13 years; 74% males; 85% with NSTE-myocardial infarction). Overall, 350 (78%), 63 (14%) and 35 (8%) patients had a low, moderate or high-SYNTAX score, respectively. Thirty-one (7%) patients had significant left main disease. At multivariate analysis (adjusted for age, diabetes, renal function, GRACE and TIMI scores), the HEART score (hazard ratio 2.3, 95% confidence interval 1.5–3.3, p7 showed a sensitivity of 76% and specificity of 75% in identifying such patients. Conclusion In this cohort of NSTE-ACS patients, the HEART score was an independent predictors of complex coronary anatomies. These results suggest that those with high (>7) HEART score may merit from SAPT as opposed to DAPT, given the high probability of complex lesions amenable to CABG. Funding Acknowledgement Type of funding sources: None.

Background Exercise capacity is usually reduced in Fontan patients, however there is a subset of patients who have normal exercise capacity and better outcomes, the “Super-Fontans”. The aim of this study was to characterize a cohort of Fontan patients undergoing cardiopulmonary exercise testing (CPET) and identify predictors of better functional capacity. Methods Single center retrospective analysis of consecutive Fontan patients aged >10 years old who underwent CPET, between March 2018 and May 2021. Peak respiratory exchange ratio1.05 defined maximal CPET. Peak VO2 (pVO2) as a percentage of its predicted value was used as reference value to stratify patients in tertiles. Patients in 3rd tertile, with a percentage predicted pVO2 superior to 75%, were considered good-performers. Blood tests and transthoracic echocardiogram (TTE) were performed on the same day. Additional data were collected from electronic charts. Results In total, 49 patients were included (mean age 19±7 years old, 67% male) with intra or extracardiac conduit implanted in mean 12±7 years prior to the CPET. The most common primary diagnoses were tricuspid/pulmonary atresia (43%), followed by unbalanced complete AV septal defect (14%) and double inlet left ventricle (14%). 12 patients had a systemic right ventricle. All, except 5 patients, had preserved systolic ventricular function and 37% had moderate to severe AV regurgitation. The majority had normal hemoglobin levels (median 15.6 g/dL), hepatic enzymes (median total bilirubin 0.8 mg/dL), renal function (median creatinine 0.8 mg/dL) and low NT-proBNP (median 122 pg/mL). All patients had maximal CPET, median %VO2 at VT1 was 57% of peak and mean pVO2 was 66±14% of the predicted. Most patients (69%) showed exercise limitation due to cardiovascular cause, followed by O2 desaturation, present in 22% of CPETs. The age of Fontan completion was not associated with functional capacity (p=0.6). The good-performer group comprised 13 patients (27%), all in sinus rhythm, of which 10 were physically active. Compared with the remainder, this group had higher VO2 at VT1 (18.7 vs. 14.6, p=0.01) and VO2 at VT2 (25.9 vs. 22.1, p=0.02), both in mL/kg/min. Also, peak heart rate (% predicted) (90 vs. 81, p=0.03) was higher in this subgroup – fig.1. Conversely, differences on TTE parameters (GLS and AV valve regurgitation) and blood biomarkers were not statistically significant. On multivariable analysis, no single variable predicted better functional capacity. Conclusion In our Fontan cohort, most patients had reduced exercise capacity, largely due to cardiovascular dysfunction. However, “Super-Fontans” stood out as they had a higher anaerobic threshold illustrating their better physical condition. These findings highlight the role of regular physical activity in Fontan patients as a cornerstone for better functional capacity. Funding Acknowledgement Type of funding sources: None.

Background Adult Congenital Heart Disease (ACHD) patients at increased risk for thromboembolic events are often treated with oral anticoagulation. While vitamin-K antagonists have been the agent of choice for decades, the use of non-vitamin K oral anticoagulants (NOAC) is increasing. We aimed to assess the safety and effectiveness of NOAC in ACHD patients at our centre. Methods This is a single-centre study enrolling all patients with ACHD treated with a NOAC from inception to November 2021. Data was collected using a standardized questionnaire applied to all patients by means of a telephone visit, in parallel with a detailed retrospective chart review. The endpoints of interest included thromboembolic and haemorrhagic events, defined as per the standardized International Society on Thrombosis and Haemostasis (ISTH) scale. Results Overall, 36 ACHD patients were enrolled [mean age 53±15 years; female sex – 66.7%; previous stroke – 33.3%; median HAS-BLED and CHA2DS2-VASc score – 1 (1–2) and 3 (2–5), respectively], predominantly with moderate or complex congenital defects (52.7%), of whom 14, 8, 8 and 4 were treated with rivaroxaban, apixaban, edoxaban and dabigatran, respectively. Two-thirds had their first NOAC prescription in the latest 3 years (Figure 1). The most common indication for anticoagulation was atrial fibrillation or flutter (77.8%). Over a median time of 36 (18–63) months on NOAC treatment, there were no patients with thromboembolic events, whilst 13 (36.1%) had a haemorrhagic event – annualized event rate of 12.0 (6.9–24.1%). All bleeding events were minor, most often self-limited gingival haemorrhage or epistaxis (n=7) or menorrhagia (n=3). Nasal cautery was needed to treat recurrent epistaxis in 3 patients, whilst 3 other required oral iron supplementation. The strongest predictor of any haemorrhage was a prior cardiovascular hospitalization (HR 3.88; p=0.027). Conclusions The use of NOAC in ACHD patients has been increasing in our centre, with encouraging results. The present findings suggest that NOAC are safe and may be effective for thromboembolic event prevention in heterogeneous forms of ACHD. Funding Acknowledgement Type of funding sources: None.

The development of implant metal-free surfaces has gained attention since non-benefic results have been reported related to the metallic ions released from metal implants to the human body. Ceramic coatings have been proposed as a possible solution however, the detachment of these coatings, during implantation or even in function, can compromise its function. In order to overcome this problem, this work proposes a novel hybrid Ti6Al4V-ZrO

Despite the reported high success of dental implants, problems related to biofilm formation and peri-implantitis due to the entrance and proliferation of bacteria on the peri-implant zone have increasing attention. In this sense, this work proposes a new zirconia surface with micro-grooves aiming to develop an effective tight seal between artificial soft tissue and implant surface and thus, to protect from bacterial invasion. In this study, different laser and design parameters were tested to produce successive micro-grooves with different and variated depth, width and wall. The micro-grooves were produced by a Nd:YAG laser and were morphologically characterized by SEM. Higher marked depths were obtained for a high number of laser passages under low scan speed as a result of a high amount of laser energy density. The most adequate conditions were mechanically tested regarding their capacity to retain artificial soft tissue (mimicking natural gingiva) by mechanical tensile strength test. The strength of adhesion between soft tissue and the micro-grooved surface revealed to be strongly dependent on the depth and width. The obtained results showed that the production of successive micro-grooves on the zirconia surface increased the adhesion of artificial soft tissue to its surface, proving that laser technology is a promising approach for the manufacturing of implants with micro-grooves sites that can protect from bacterial invasion.

This work presents innovative zirconia surfaces functionalized with gold nanoparticles (Aunps) and silver microparticles (Agμps) through versatile laser technology where laser parameters and subtractive/additive strategies were combined to apply in dental implant surfaces regarding antibacterial potentialities. Aunps-functionalized zirconia surfaces were produced by a hybrid process starting with nanoparticles production by Nd:YAG laser ablation, followed by its deposition through spray system and its adhesion to the zirconia surface by the laser CO2 action, varying laser power and scan speed parameters. Agμps-functionalized zirconia surfaces were obtained through a hybrid laser process starting by laser texturing of the compacted zirconia surface, followed by allocation of Ag powder into the texture and its subsequent laser sintering, varying laser power. The functionalized zirconia surfaces were analyzed through SEM/EDS. In order to mimic the implant screwing effect, the samples were subjected to reciprocating friction tests against bone. It allows to evaluate the adhesion of the zirconia surface to the bone and the resistance to surface detachment. A purple colloidal solution of spherical gold nanoparticles with an average size of 5 ± 3 nm was successfully produced by laser. The friction tests revealed a good behavior of both functionalized zirconia surfaces indicating that their integrity is not affected during implant screwing insertion. A good dispersion of nanoparticles on the zirconia surface was observed indicating that the spray system is an effective way to deposit nanoparticles on the surface. A high amount of agglomerates was found for samples where low laser power (P = 11W) and scan speed (v = 1000 mm/s) were applied, probably due to the high density of energy (E). A decrease of defects on the sintered Ag layer with increasing laser power from 3 to 6 W was found, mainly related with the amount of laser energy density. The ion release showed to be strongly dependent on particle size.

Zirconia is becoming reckoned as a promising solution for different applications, in particular those within the dental implant investigation field. It has been proved to successfully overcome important limitations of the commonly used titanium implants. The adhesion of microorganisms to the implants, in particular of bacteria, may govern the success or the failure of a dental implant, as the accumulation of bacteria on the peri-implant bone may rapidly evolve into periodontitis. However, bacterial adhesion on different zirconia architectures is still considerably unknown. Therefore, the adhesion of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa to zirconia surfaces with different finishings was evaluated and compared to a titanium surface. The adhesion interaction between S. aureus and P. aeruginosa was also evaluated using a co-culture since these bacteria are infamous due to their common presence in chronic wound infections. Results showed that different bacterium species possess different properties which influence their propensity to adhere to different roughness levels and architectures. E. coli revealed a higher propensity to adhere to zirconia channelled surfaces (7.15 × 106 CFU/mL), whereas S. aureus and P. aeruginosa adhered more to the titanium control group (1.07 × 105 CFU/ mL and 8.43 × 106 CFU/mL, respectively). Moreover, the co-culture denoted significant differences on the adhesion behaviour of bacteria. Despite not having shown an especially better behaviour regarding bacterial adhesion, zirconia surfaces with micro-channels are expected to improve the vascularization around the implants and ultimately enhance osseointegration, thus being a promising solution for dental implants., This work was supported by FCT-Portugal through the grant PD/BD/140202/2018, and the projects POCI-01-0145-FEDER-030498, POCI-01-0247-FEDER-017828, UIDB/04436/2020 and UIDP/04436/2020. This work was also funded by FEDER funds through the Operational Competitiveness Program-COMPETE and by National Funds through FCT-under the projects PTDC/CTM-TEX/28295/2017 and UID/CTM/00264/2019.

Background Femoral access is considered the gold standard for transcatheter aortic valve implantation (TAVI). However, this route might be precluded due to the presence of tortuosity, small vessel diameter and/or peripheral artery disease. We aimed to investigate TAVI through an alternative access (AA), focusing on the selection criteria and clinical outcomes compared to the femoral route (TF). Methods We conducted an all-comers longitudinal single-centre prospective registry in whom a TAVI was performed. The feasibility, safety and efficacy of TAVI by means of an access route other than standard TF was assessed, according to the VARC-2 criteria. The prospective surgical criteria used at our institution to accept an AA route were: a) TF deemed inappropriate; b) acceptable haemorrhagic risk; c) acceptable general anaesthesia risk; and d) adequate anatomy and diameter within acceptable range (subclavian, axillar, transaortic) or e) age Results From 2008 to 2018, there were 548 patients submitted to TAVI [median age 84 (79–87) years, males 45.4%]. An AA route was used in 100 patients (79 trans-apical, 9 trans-aortic, and 12 trans-subclavian), with a decreasing rate over follow-up (−11% per year). Compared to TF, these patients were younger [80 (77–84) vs. 85 (80–87) years; p Conclusion In the first 10 years of experience, 1 in every 6 patients was treated with a TAVI by means of an AA, most often trans-apically initially and, nowadays, via a trans-subclavian approach. The use of meticulous prospective selection criteria seems to explain the one-year similar results, regardless of the access route. Funding Acknowledgement Type of funding sources: None.

Introduction Approximately half of transcatheter aortic valve implantaton (TAVI) candidates have coronary artery disease (CAD). Controversial results have been reported regarding the effect of the presence/severity of CAD and its management on clinical outcomes post-TAVI. Aim To describe the presence, extension, severityand management of CAD pre-TAVIand to evaluate its impact on 2-yearmortality in areal world all comers population. Methods and population Single centre retrospective analysis from a prospectively collected institutional registry (VCROSS) including 517 patients that underwent TAVI for severe aortic stenosis between January 2009 and December 2018. Patients who underwent pre TAVI CA in the context of ACS or at other institution were excluded n=138. Ultimately 380 entered the analysis. Obstructive CAD was defined as stenosis >50% in in major epicardial vessels (>2.5 mm). The total number of major epicardial with obstructive CAD was reported as was assessed the number of those left untreated. Univariate analysis was performed to assess 1) differences between patients with or without CAD and between those with significant CAD who have or have not undergone PCI, 2) variables associated with 2-year mortality. Binary logistic regression was performed to identify independent predictors of 2-year mortality including the presence of significant CAD and the type of management. Results A total of 380 patients were included, 55.3% male with an average age of 83YO (±6.3), mean Euroscore II of 4.35. 76 had previous coronary artery bypassgrafting (CABG) and 136 had previous PCI (43 had both). 55 patients (14.4%) presented with normal coronary arteries, 120 (31.6%) with non-obstructive CAD and 205 (54%) with obstructive CAD. Out of the latter, 112 (29.5%) underwent PCI. Statistically significant differences were found between obstructive CAD vs non-obstructive patients in terms of age, previous history of ICP and CABG. In the subgroup population with obstructive CAD, no statistically significant differences was found in the PCI vs non PCI group, apart from previous history of ICP and CABG – Figure 1. Diabetes mellitus, previous history of percutaneous coronary intervention (PCI) and reduced ejection fraction (rEF – defined has Conclusion The presence and type of management of obstructive CAD in this real world all comers registry did not impact the prognosis at 2 years. Funding Acknowledgement Type of funding sources: None.

Contrarily to conventional sintering (CS) method where longer cycles and high temperature (1400–1500 °C) are applied to sinter yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP) ceramics, this work presents a faster and low temperature (1175 °C) way through hot pressing (HP) to produce full densified zirconia with good mechanical and tribological properties. This work is concerned with the influence of sintering pressure on the microstructure and tribological properties of hot-pressed Y-TZP. For this purpose, four sintering pressures 5, 20, 60 and 100 MPa were tested. The wear tests were carried out by reciprocating ball-on-plate as a simplified test for tooth-to-restorative material contact under 37 °C using artificial saliva to mimic oral conditions. The results demonstrated that density, hardness and tribological properties are strongly influenced by the sintering pressure, namely an improvement with pressure increase was achieved. The highest density, hardness values and wear resistance were achieved for Y-TZP samples produced at P = 100 MPa. Furthermore, it was revealed that a smaller grain size for Z100 samples (full densification condition) was achieved comparatively to conventional-sintered Y-TZP. This work proves that it is possible to produce dense Y-TZP materials under low sintering temperature and faster cycles with reduced grain size without compromise mechanical and tribological properties.

Yttria-stabilized zirconia (YSZ) is being proposed as an alternative material to Titanium for dental implants due to its aesthetic and biocompatibility properties. However, is it yet to define the optimal surface treatment to improve YSZ bioactivy. Texturization is a promising approach, but the biological role of patterned YSZ surfaces in cell cultures is yet to be determined. Thus, cellular behavior of osteoblasts and fibroblasts in contact with groove-texturized YSZ surfaces was investigated. YSZ discs were groove-textured by conventional milling and Nd:YAG laser. All samples including control were sandblasted and acid-etched. Human osteoblasts and fibroblasts were cultured on discs for 14 days. Morphology and cellular adhesion were observed. Cell viability, interleukin-1β, osteopontin, collagen type I prodution, alkaline phosphatase activity, and interleukin-8 were measured. YSZ texturization by conventional milling improved osteoblasts viability and differentiation when compared to laser texturization. Fibroblasts behavior did not seem to be influenced by the texturing technique. Compared to sandblasting and acid etching currently used as gold standard for zirconia dental implants no superiority of macrotexturization was found.

Background The ability of a high level of dietary Arthrospira platensis, individually or in combination with two exogenous carbohydrate-degrading enzymes (lysozyme and Rovabio®), to improve systemic antioxidant potential and hepatic lipid metabolism was tested in piglets. Forty male post-weaned piglets, sons of Large White × Landrace sows crossed with Pietrain boars, were allocated into 4 groups (n = 10) and fed during 28 days one of the following diets: 1) a control basal diet (cereal and soybean meal); 2) a basal diet with 10% of A. platensis (AP); 3) the AP diet supplemented with 0.005% of Rovabio® (AP + R); 4) the AP diet supplemented with 0.01% of lysozyme (AP + L). Results Arthrospira platensis decreased BW gain of piglets, regardless the addition of feed enzymes. The majority of plasma metabolites were affected by diets. A. platensis increased total lipids, total cholesterol and LDL-cholesterol, without changing hepatic fatty acid content or modulating, in an expressive manner, the transcriptional profile of lipid sensitive mediators. The antioxidant potential in general, and total carotenoids in particular, were improved by the microalga, regardless lysozyme or Rovabio®. Conclusions Summing up, A. platensis, individually and combined with feed enzymes, impacts negatively on piglets’ growth but improves the systemic antioxidant potential and changes plasma lipids with a minor modulation on related hepatic metabolic pathways.

Additional file 2: Table S2. Primer sequences and PCR conditions.

In this work we deal with the asymptotic stabilization problem of polynomial (and rational) input-affine systems subject to parametric uncertainties. The problem of linear static output feedback (SOF) control synthesis is handled, having as a prerequisite a differential algebraic representation (DAR) of the plant. Using the property of strict QSR-dissipativity, theFinsler's Lemma and the notion of linear annihilators we introduce a new dissipativity-based strategy for robust stabilization which determines a static feedback gain by solving a simple linear semidenite program on a polytope. At the same time, an estimate of the closed-loop domain of attraction is given in terms of an ellipsoidal set. The novelty of the proposed approach consists in this combination of dissipativity theory and powerful semidenite programming(SDP) tools allowing for a simple solution of the challenging problem of static output feedback design for nonlinear systems. A numerical example allows the reader to verify the applicability of the proposed technique.