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Over the last decade, as a consequence of the global decarbonization process, the interest towards green hydrogen production has drastically increased. In particular a substantial research effort has focused on the efficient and affordable production of carbon-free hydrogen production processes. In this context, the development of more efficient electrolyzers with low-cost electrode/electrocatalyst materials can play a key role. This work, investigates the fabrication of electrodes of nickel-zinc alloys with nanowires morphology cathode for alkaline electrolyzers. Electrodes are obtained by the simple method of template electrosynthesis that is also inexpensive and easily scalable. Through the analysis of the morphological and chemical composition of nanowires, it was found that the nanowires composition is dependent on the concentration of two metals in the deposition solution. Electrocatalytic tests were performed in 30% w/w potassium hydroxide aqueous solution at room temperature. In order to study the electrodes stability, mid-term galvanostatic test was also carried out. All electrochemical tests show that nanowires with about 44.4% of zinc have the best performances. Particularly, at −50 mAcm−2, these electrodes have an overpotential 50 mV lower than pure Ni nanowire. NiZn nanowires show also a good stability over time without noticeable signs of performance decay.

The fabrication and characterization of nickel-alloy electrodes for alkaline electrolysers is reported. Three different alloys (Ni–Co, Ni–Zn and Ni–W) at different composition were studied in order to determine the optimum condition. Nanostructured electrodes were obtained by template electrodeposition into a nanoporous membrane, starting from aqueous solution containing the two elements of the alloy at different concentrations. Composition of alloys can be tuned by electrolyte composition and also depends on the difference of the redox potential of elements and on the presence of complexing agents in deposition bath. Electrochemical and electrocatalytic tests, aimed at establishing the best alloy composition, were carried out for hydrogen evolution reaction. Then, test conducted at a constant current density in potassium hydroxide (30% w/w) aqueous solution were also performed. For all investigated alloys, very encouraging results were obtained and in particular Ni–Co alloys richer in Co showed the best performance.

As ever-increasing amounts of renewable electricity enter the energy supply mix on a regional, national and international basis, greater emphasis is being placed on energy conversion and storage technologies to deal with the oscillations, excess and lack of electricity. Hydrogen generation via proton exchange membrane water electrolysis (PEMWE) is one technology that offers a pathway to store large amounts of electricity in the form of hydrogen. The challenges to widespread adoption of PEM water electrolyzers lie in their high capital and operating costs which both need to be reduced through R&D. An evaluation of reported PEMWE performance data in the literature reveals that there are excessive variations of in situ performance results that make it difficult to draw conclusions on the pathway forward to performance optimization and future R&D directions. To enable the meaningful comparison of in situ performance evaluation across laboratories there is an obvious need for standardization of materials and testing protocols. Herein, we address this need by reporting the results of a round robin test effort conducted at the laboratories of five contributors to the IEA Electrolysis Annex 30. For this effort a method and equipment framework were first developed and then verified with respect to its feasibility for measuring water electrolysis performance accurately across the various laboratories. The effort utilized identical sets of test articles, materials, and test cells, and employed a set of shared test protocols. It further defined a minimum skeleton of requirements for the test station equipment. The maximum observed deviation between laboratories at 1 A cm−2 at cell temperatures of 60 °C and 80 °C was 27 and 20 mV, respectively. The deviation of the results from laboratory to laboratory was 2–3 times higher than the lowest deviation observed at one single lab and test station. However, the highest deviations observed were one-tenth of those extracted by a literature survey on similar material sets. The work endorses the urgent need to identify one or more reference sets of materials in addition to the method and equipment framework introduced here, to enable accurate comparison of results across the entire community. The results further imply that cell temperature control appears to be the most significant source of deviation between results, and that care must be taken with respect to break-in conditions and cell electrical connections for meaningful performance data.

In this work, the galvanic deposition method is used to deposit coatings of brushite/hydroxyapatite/polyvinyl acetate on 304 stainless steel. Coatings are obtained at different temperatures and with different sacrificial anodes, consisting of a mixture of brushite and hydroxyapatite. Samples are aged in a simulated body fluid (SBF), where a complete conversion of brushite into hydroxyapatite with a simultaneous change in morphology and wettability occurred. The corrosion tests show that, compared with bare 304, the coating shifts Ecorr to anodic values and reduces icorr Ecorr, and icorr has different values at different aging times due to chemical interactions at the solid/liquid interface. The best performing deposits are those obtained by using Al as the sacrificial anode. The metal ion release, measured after 21 days of aging, is very low and is attributable to the presence of a coating that slows the steel corrosion. Coating cytotoxicity is investigated through cell viability assays with MC3T3-E1 osteoblastic cells. The results reveal a high cytocompatibility comparable to that of a pure cell culture medium.

Hydrogen is an excellent energy source for long-term storage and free of greenhouse gases. However, its high production cost remains an obstacle to its advancement. The two main parameters contributing to the high cost include the cost of electricity and the cost of initial financial investment. It is possible to reduce the latter by the optimization of system design and operation conditions, allowing the reduction of the cell voltage. Because the CAPEX (initial cost divided by total hydrogen production of the electrolyzer) decreases according to current density but the OPEX (operating cost depending on the cell voltage) increases depending on the current density, there exists an optimal current density. In this paper, a genetic algorithm has been developed to find the optimal evolution parameters and to determine an optimum electrolyzer design. The optimal current density has been increased by 10% and the hydrogen cost has been decreased by 1%.

INTRODUCTION: Hypertonic saline solution (HSS) and a moderate Na restriction plus high furosemide dose showed beneficial effects in compensated heart failure (HF), in short and long terms. The study was aimed to verify the effects of this combination on hospitalization time, readmissions and mortality in patients in New York Heart Association (NYHA) class III. METHOD: Chronic ischemic or nonischemic cardiomyopathy uncompensated patients with HF in NYHA III functional class with ejection fraction

BACKGROUND: beta-blockers in ST-segment elevation myocardial infarction (STEMI) are indicated for patients without a contraindication, particularly in patients with high heart rates (HR) or blood pressures. Epidemiological studies have shown that elevated HR represents a risk factor for cardiovascular morbidity. The study investigates the feasibility, tolerability, and the effects after 30 days of follow-up of ivabradine (IVA) versus metoprolol (METO) in early phases of anterior STEMI reperfused by percutaneous coronary intervention (PCI). METHODS AND RESULTS: Patients with a first anterior STEMI, Killip class I-II, an acceptable echocardiographic window, and admitted within 4hours of the onset of symptoms, with an ejection fraction

The aim of the present study was to evaluate the safety and efficacy of the combination of indomethacin and statin compared with indomethacin plus placebo in patients with a first episode of pericarditis. A total of 55 consecutive patients with acute pericarditis were randomized in a double-blind manner into two groups: group I (statin group) was treated with 150 mg of indomethacin plus 10 mg of rosuvastatin, and group 2 (placebo group) was treated with 150 mg of indomethacin plus placebo. Both groups received treatment up to the normalization of inflammation markers and for the following week. Clinical and laboratory assessments [white cell count, ESR (erythrocyte sedimentation rate) and CRP (C-reactive protein), troponin I, creatine kinase and brain natriuretic peptide plasma levels], ECG and echocardiogram were performed at baseline and daily up to discharge. All of the patients were followed as outpatients for 3 months to evaluate any recurrence of pericarditis. The two groups were similar in age, sex and laboratory parameters [group I (the statin group), n = 28 patients; gender, 18 male and ten female; and age, 29.5 ±5.7 years; group 2 (placebo group), n=27 patients; gender, 16 male/I I female; and age, 29.2±4.8 years]. The statin group, when compared with the placebo group, had a significantly faster reduction in CRP values (5.0 ± 1.0 compared with 6.0 ± 2.0 days respectively; P = 0.022), ST segment normalization (3.5 ± 1.0 compared with 4.5 ± 1.0 days respectively; P=0.001), pericardial effusion (4.5 ± 1.0 compared with 5.5 ± 1.0 days respectively; P = 0.001) and ESR (5.0 ± I compared with 6.0 ± 2 days respectively; P=0.022). Our results show that the combination of statin and indomethacin treatment in patients with acute pericarditis is feasible, with a significant reduction in inflammatory markers and a favourable trend in hospitalization time (5.5 ± 2.0 compared with 6.5 ± 2.0 days respectively; P= 0.069). However, these preliminary findings require further studies in a larger sample of patients.

Background: There are several new strategies proposed to improve the outcome of patients with ST-elevation myocardial infarction (STEMI). One approach is the resurgent use of facilitated percutaneous coronary interventions (PCI). Until recently, deciding whether immediate PCI after combined treatment (facilitated PCI) is more appropriate than delayed PCI (short time) has not been investigated. The aim of this study, therefore, was to investigate the outcomes in patients initially successfully treated pharmacologically and immediate PCI < 2 hr, and in patients initially successfully treated with pharmacological therapy and with delayed PCI (12–72 h). Methods: 451 reperfused STEMI patients, aged 18 to 75 years, class I–II Killip, with an acceptable echocardiographic window and admitted within 12 hs of the onset of symptoms were randomized into two groups. All patients had to have successful reperfusion, to receive the combination of a standard tirofiban infusion or abciximab plus half dose rtPA. Thereafter, patients were sub-grouped as follows:group 1 (immediate PCI) patients had PCI within 2 h; and group 2 (delayed PCI) patients in which PCI was performed after 12 hs and within 72 hs. Results: The 225 reperfused (immediate-PCI) and 226 reperfused (delayed-PCI) patients (time from randomization to PCI 165 ± 37 min in immediate PCI versus 45.1 ± 20.2 h in delayed PCI group) showed similar results in ejection fraction, CK release and patency of the IRA. In addition, the delayed PCI group showed a significant reduction in ischemic events, restenosis and bleedings (P = 0.005, 0.01, 0.01 respectively) and significant reduced angiographic evidence of thrombus formation in the infarction-related artery (IRA) (p = 0.001). Conclusion: Our data suggest the safety and possible use of delayed facilitated PCI in patients with STEMI, and that delayed PCI in patients treated with combined lytic and IIb/IIIa inhibitors appears to be as effective and possibly superior (reduced ischemic events and repeat PCI) as immediate PCI. The patients in this study were successfully reperfused, with TIMI-3 flow and our data may not apply to patients with TIMI 0–2 flow. This strategy could allow transferring the reperfused patients and performing PCI after hours < 72 hours and not immediately, thereby reducing the number of urgent PCI and costs, obtaining similar results, but mostly causing less discomfort to the patient. Our results had to be interpreted with caution, because current guidelines do not recommend the combined therapy, but suggest further studies. The study was aimed to investigate the outcomes in patients initially successfully treated pharmacologically and immediate PCI < 2 h, and in patients initially successfully treated with pharmacological therapy and delayed PCI (12–72 h). All patients had to have successful reperfusion, to receive the combination of a standard abciximab or tirofiban infusion plus half dose rtPA. Similar results were observed in both groups. Delayed PCI group showed a significant lower incidence in restenosis (0.01), minor bleedings (0.005), ischemic events (0.01) and a reduced angiographic evidence of thrombus formation in IRA (0.001). Our data suggest the safety and possible use of delayed facilitated PCI in patients with STEMI. Our results had to be interpreted with caution, because current guidelines do not recommend the combined therapy, but suggest further studies.

Introduction The aim of this study was to assess the effect of thrombolysis versus heparin treatment on echocardiographic parameters and clinical outcome, during hospitalization and within the first 180 days after admission, in patients with first episode of submassive pulmonary embolism (SPE) and right ventricle dysfunction (RVD). Methods Consecutive patients (age, 18–75 years) with a first episode of SPE, symptoms onset since no more than 6 hours, normal blood pressure (> 100 mm Hg), echocardiographic evidence of RVD and positive lung spiral computed tomography were double-blind randomized: 1 group received 100 mg of alteplase (10-mg bolus, followed by a 90-mg intravenous infusion over a period of 2 hours), while the other group received matching placebo. In addition to alteplase or placebo, both groups received an unfractionated heparin treatment. Echocardiogram was performed at admission, at 24, 48 and 72 hours, at discharge and at 3 and at 6 months after randomization. Results Seventy-two patients were included into the study; 37 were assigned to thrombolysis and 35 to placebo. Both groups were well matched with regard to features and clinical presentation. Thrombolysis group showed a significant early improvement of RV function compared with heparin group, and this improvement was observed also during the follow-up (180 days). The same group also showed significant reduction in clinical events during the hospitalization and follow-up. Conclusions Our data suggest that, in hemodynamically stable patients with SPE, thrombolysis shows an earliest reduction of RVD and a more favorable trend in clinical outcome, so, it could merit consideration in SPE.