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M1-M2-N-C bimetallic catalysts with M1 as Fe and Co and M2 as Fe, Co, Ni and Mn were synthesized and investigated as cathode catalysts for oxygen reduction reaction (ORR). The catalysts were prepared by Sacrificial Support Method in which silica was the template and aminoantipyrine (AAPyr) was the organic precursor. The electro-catalytic properties of these catalysts were investigated by using rotating ring disk (RRDE) electrode setup in neutral electrolyte. Fe-Mn-AAPyr outperformed Fe-AAPyr that showed higher performances compared to Fe-Co-AAPyr and Fe-Ni-AAPyr in terms of half-wave potential. In parallel, Fe-Co-AAPyr, Co-Mn-AAPyr and Co-Ni-AAPyr outperformed Co-AAPyr. The presence of Co within the catalyst contributed to high peroxide production not desired for efficient ORR. The catalytic capability of the catalysts integrated in air-breathing cathode was also verified. It was found that Co- based catalysts showed an improvement in performance by the addition of second metal compared to simple Co- AAPyr. Fe-based bimetallic materials didn't show improvement compared to Fe-AAPyr with the exception of Fe-Mn-AAPyr catalyst that had the highest performance recorded in this study with maximum power density of 221.8 ± 6.6 mWcm2. Activated carbon (AC) was used as control and had the lowest performances in RRDE and achieved only 95.6 ± 5.8 mWcm2 when tested in MFC.

In the past 10-15 years, the microbial fuel cell (MFC) technology has captured the attention of the scientific community for the possibility of transforming organics directly into electricity through microbially catalyzed anodic, and microbial/enzymatic/abiotic cathodic electrochemical reactions. In this review, several aspects of the technology are considered. Firstly, a brief history of abiotic to biological and subsequently, microbial fuel cells is presented. Secondly, the development of the concept of microbial fuel cell into a wider range of derivate technologies, called bioelectrochemical systems, is described introducing briefly microbial electrolysis cells, microbial desalination cells and microbial electrosynthesis cells. The focus is then shifted to electroactive biofilms and electron transfer mechanisms involved with solid electrodes. Carbonaceous and metallic anode materials are then introduced, followed by the electro catalysis of the oxygen reduction reaction and its behavior in neutral media is explained, from recent studies. Cathode catalysts based on carbonaceous, platinum-group metal and platinum-group-metal-free materials are presented, along with membrane materials with a view to future directions. Finally, microbial fuel cell practical implementation, with utilisation of energy output for practical applications, is described.

The oxygen reduction reaction (ORR) is one of the major factors that is limiting the overall performance output of microbial fuel cells (MFC). In this study, Platinum Group Metal-free (PGM-free) ORR catalysts based on Fe, Co, Ni, Mn and the same precursor (Aminoantipyrine, AAPyr) were synthesized using identical sacrificial support method (SSM). The catalysts were investigated for their electrochemical performance, and then integrated into an air-breathing cathode to be tested in “clean” environment and in a working microbial fuel cell (MFC). Their performances were also compared to activated carbon (AC) based cathode under similar conditions. Results showed that the addition of Mn, Fe, Co and Ni to AAPyr increased the performances compared to AC. Fe-AAPyr showed the highest open circuit potential (OCP) that was 0.307 ` 0.001 V (vs. Ag/AgCl) and the highest electrocatalytic activity at pH 7.5. On the contrary, AC had an OCP of 0.203 ` 0.002 V (vs. Ag/AgCl) and had the lowest electrochemical activity. In MFC, Fe- AAPyr also had the highest output of 251 ` 2.3 mWcm"2, followed by Co-AAPyr with 196 ` 1.5 mWcm"2, Ni-AAPyr with 171 ` 3.6 mWcm"2, Mn-AAPyr with 160 ` 2.8 mWcm"2 and AC 129 ` 4.2 mWcm"2. The best performing catalyst (Fe-AAPyr) was then tested in MFC with increasing solution conductivity from 12.4 mScm"1 to 63.1 mScm"1. A maximum power density of 482 ` 5 mWcm"2 was obtained with increasing solution conductivity, which is one of the highest values reported in the field.

Catalytic activity towards the oxygen reduction reaction (ORR) of PGM-free electrocatalysts integrated with an enzyme (bilirubin oxidase, BOx) in neutral media was studied. The effects of chemical and morphological characteristics of PGM-free materials on the enzyme enhancement of overall kinetics was investigated. The surface chemistry of the PGM-free catalyst was studied using X-ray Photoelectron Spectroscopy. Catalyst surface morphology was characterized using two independent methods: length-scale specific image analysis and nitrogen adsorption. Good agreement of macroscopic and microscopic morphological properties was found. Enhancement of ORR activity by the enzyme is influenced by chemistry and surface morphology of the catalyst itself. Catalysts with a higher nitrogen content, specifically pyridinic moieties, showed the greatest enhancement. Further, catalysts with a higher fraction of surface roughness in the range of 3-5 nm exhibited greater performance enhancement than catalysts lacking features of this size.

Three-dimensional graphene nanosheets (3D-GNS) were used as cathode catalysts for microbial fuel cells (MFCs) operating in neutral operating conditions. 3D-GNS catalysts showed high performance towards oxygen electroreduction in neutral media with high current densities and low hydrogen peroxide generation compared to activated carbon (AC). 3D-GNS was incorporated into air-breathing cathodes based on AC with three different loadings (2, 6 and 10 mgcm-2). Performances in MFCs showed that 3D-GNS had the highest performances with power densities of 2.059±0.003 Wm-2, 1.855±0.007 Wm-2 and 1.503±0.005 Wm-2 for loading of 10, 6 and 2 mgcm-2 respectively. Plain AC had the lowest performances (1.017±0.009 Wm-2). The different cathodes electrodes were also investigated in supercapacitive MFCs (SC-MFCs). The addition of 3D-GNS decreased the ohmic losses by 14-25%. The decrease in ohmic losses allowed the SC-MFC with 3D-GNS (loading 10 mgcm-2) to have the maximum power (Pmax) of 5.746±0.186 Wm-2. At 5 mA, the SC-MFC featured a capacitive response that increased from 0.027±0.007 F with AC to 0.213±0.026 F with 3D-GNS (loading 2 mgcm-2) and further to 1.817±0.040 F with 3D-GNS (loading 10 mgcm-2). This is the first time that a capacitance of the order of magnitude of Farads is shown related to microbial fuel cell system.

In this work, the electrodes of a microbial desalination cell (MDC) are investigated as the positive and negative electrodes of an internal supercapacitor. The resulting system has been named a supercapacitive microbial de- salination cell (SC-MDC). The electrodes are self-polarized by the red-ox reactions and therefore the anode acts as a negative electrode and the cathode as a positive electrode of the internal supercapacitor. In order to overcome cathodic losses, an additional capacitive electrode (AdE) was added and short-circuited with the SC- MDC cathode (SC-MDC-AdE). A total of 7600 discharge/self-recharge cycles (equivalent to 44 h of operation) of SC-MDC-AdE with a desalination chamber filled with an aqueous solution of 30 g L−1 NaCl are reported. The same reactor system was operated with real seawater collected from Pacific Ocean for 88 h (15,100 cycles). Maximum power generated was 1.63 ± 0.04 W m−2 for SC-MDC and 3.01 ± 0.01 W m−2 for SC-MDC-AdE. Solution conductivity in the desalination reactor decreased by ∼50% after 23 h and by more than 60% after 44 h. There was no observable change in the pH during cell operation. Power/current pulses were generated without an external power supply.

Iron(II) phthalocyanine (FePc) deposited onto two different car- bonaceous supports was synthesized through an unconven- tional pyrolysis-free method. The obtained materials were stud- ied in the oxygen reduction reaction (ORR) in neutral media through incorporation in an air-breathing cathode structure and tested in an operating microbial fuel cell (MFC) configura- tion. Rotating ring disk electrode (RRDE) analysis revealed high performances of the Fe-based catalysts compared with that of activated carbon (AC). The FePc supported on Black-Pearl carbon black [Fe-BP(N)] exhibits the highest performance in terms of its more positive onset potential, positive shift of the half-wave potential, and higher limiting current as well as the highest power density in the operating MFC of (243 7) mW cm2, which was 33 % higher than that of FePc support- ed on nitrogen-doped carbon nanotubes (Fe-CNT(N) ; 182 5 mW cm2). The power density generated by Fe-BP(N) was 92 % higher than that of the MFC utilizing AC ; therefore, the utilization of platinum group metal-free catalysts can boost the performances of MFCs significantly.

Different iron-based cathode catalysts have been studied for oxygen reduction reaction (ORR) in neutral media and then applied into microbial fuel cells (MFC). The catalysts have been synthesized using sacrifi- cial support method (SSM) using eight different organic precursors named Niclosamide, Ricobendazole, Guanosine, Succinylsulfathiazole, Sulfacetamide, Quinine, Sulfadiazine and Pyrazinamide. Linear Sweep Voltammetry (LSV) curves were obtained for the catalysts using a O2 saturated in 0.1 M potassium phos- phate buffer and 0.1 M KCl solution and a Rotating Ring Disk Electrode (RRDE) setup in order to study the ORR characteristics. Additionally, we analyze the peroxide yield obtained for each catalyst which helps us determine the reaction kinetics. Those catalysts have been mixed with activated carbon (AC), carbon black (CB) and PTFE and pressed on a metallic mesh forming a pellet-like gas diffusion electrode (GDE). Results showed that Fe-Ricobendazole, Fe-Niclosamide and Fe-Pyrazinamide had the highest cathode polarization curves and highest power densities output that was above 200 Wcm−2 . Fe-Ricobendazole, Fe-Niclosamide, Fe-Pyrazinamide, Fe-Guanosine Fe-Succinylsulfathiazole and Fe-Sulfacetamide outper- formed compared to Pt cathode. Fe-Sulfadiazene and Fe-Quinine performed better than AC used as control but less than Pt. Correlation of surface composition with performance showed that power density achieved is directly related to the total amount of nitrogen, and in particularly, N coordinated to metal and pyridinic and pyrrolic types while larger amounts of graphitic nitrogen result in worse performance.

Platinum group metal-free (PGM-free) catalysts based on M-N-C types of materials with M as Mn, Fe, Co and Ni and aminoantipyrine (AAPyr) as N-C precursors were synthesized using sacrificial support method. Catalysts kinetics of oxygen reduction reaction (ORR) was studied using rotating ring disk electrode (RRDE) in neutral pH. Results showed that performances were distributed among the catalysts as: Fe-AAPyr N Co-AAPyr N Mn- AAPyr N Ni-AAPyr. Fe-AAPyr had the highest onset potential and half-wave potential. All the materials showed similar limiting current. Fe-AAPyr had an electron transfer involving 4e− with peroxide formed lower than 5%. Considering H2O2 produced, it seems that Co-AAPyr, Mn-AAPyr and Ni-AAPyr follow a 2 × 2e− mechanism with peroxide formed during the intermediate step. Durability test was done on Fe-AAPyr for 10,000 cycles. Decrease of activity was observed only after 10,000 cycles.

In this work, novel catalysts derived from iron and benzimidazole and aminobenzimidazole were synthesized using Sacrificial Support Method (SSM). The catalysts obtained were then tested in rotating ring disk electrode (RRDE) technique and compared with AC. Fe-based catalysts had performances much higher compared to AC and therefore are suitable for microbial fuel cell (MFC) applications. Future works will integrate the catalysts into air-breathing cathodes and test them in MFCs.

The Special Section “Microbial fuel cells: From fundamentals to applications” covers many diverse and multidisciplinary aspects of the entire microbial electrochemical field, with a special emphasis on microbial and abiotic/microbial electron transfer mechanisms at the anode and cathode electrodes. New materials are presented as low-cost catalysts for oxygen reduction or H2 evolution reactions, as alternatives to exotic/expensive metals. Different anode materials, structures, and configurations are shown with impressive results. Anodic biofilms have been identified and extensively studied, as well as newspecies and mixed-culture biofilms. Innovative designs and working conditions of microbial electrolytic cells for H2 production or NH3 recovery with outstanding results are also presented.

An iron-nitrogen-carbon-based catalyst was used at the cathode of a microbial desalination cell (MDC) and compared with platinum (Pt) and an activated carbon (AC) cathode. The Fe-NC catalyst was prepared by using nicarbazin (NCB) as the organic precursor through a sacrificial support method (SSM). Rotating ring disk electrode (RRDE) experiments show that Fe-NCB had a higher electrocatalytic activity compared to AC and Pt. The utilization of Fe-NCB in the cathode substantially improved the performance output with an initial maximum power density of 49 2 mW cm2 in contrast to Pt and AC catalysts, which show lower values of 34 1 and 23.5 1.5 mW cm2, respectively. After four cycles, Fe-NCB catalyst lost 15% of its initial performance, but still was 1.3 and 1.8 times more active than Pt and AC, respectively. Solution conductivity inside the desalination chamber (DC) decreased by 46–55 % with every cycle. The pH of the cathodic chamber and the DC increased to 10–11, owing to the production of OH during the oxygen reduction reaction and the migration of OH into the DC. Chemical organic demand decreased by 73–83% during each cycle. It was shown that Fe-NCB and Pt had a similar coulombic efficiency (CE) of 397% and 382%, whereas AC had lower CE (245%).

Background: Nucleos(t)ide reverse transcriptase inhibitors (NRTI) toxicity may represent a threat for long-term success of combined antiretroviral therapy. Some studies have suggested a possible improvement of NRTI-related toxicity after switching to NRTI-sparing regimens. Objectives: We aimed to explore the efficacy and tolerability of switching to darunavir/ritonavir (DRV/r) plus raltegravir (RAL) while having a viral load (VL) ≤50 copies/mL in the clinical setting. Study design: Treatment-experienced HIV 1-infected patients enrolled in the ICONA Foundation Study cohort were included if they switched their current regimen to DRV/r + RAL with a HIV-RNA ≤50 copies/mL. Different definitions of virological failure (VF) and treatment failure (TF) were employed. Kaplan–Meier curves and Cox regression models were performed to estimate time to event probability. Results: We included 72 HIV-infected patients, 22 (31%) of these were female, 31 (43%) men who have sex with men (MSM) amd 15 (21%) had hepatitis co-infections. Median age was 44 (IQR: 35-50) years amd CD4 count was 389 (IQR 283-606) cells/mmc. Median follow-up time for TF was 24 (IQR 9–31) months. Twenty-five discontinuations occurred (60% simplifications); only 2 (8%) were toxicity-driven (lipid elevations). The probability of VF (confirmed VL >50 copies/mL) was estimated at 7% [95% confidence interval (CI) 1–13%] by 12 and 9% (95% CI 2–16%) by 24 months. When considering TF, we found a probability of stop/intensification/single VL > 200 copies/mL of 13% (95% CI 1–17%) and 22% (95% CI 11–33%) by 12 and 24 months. Female gender (adjusted relative hazard, ARH = 0.10; 95% CI 0.01–0.74; p = 0.024) and older age (AHR = 0.50 per 10 years older; 95% CI 0.25–0.99; p = 0.045) were associated with a lower risk of TF. A previous PI failure was strongly associated with TF (AHR = 52.6, 95% CI 3.6–779; p = 0.004). Co

We report 281 individuals carrying a pathogenic recurrent NF1 missense variant at p.Met1149, p.Arg1276, or p.Lys1423, representing three nontruncating NF1 hotspots in the University of Alabama at Birmingham (UAB) cohort, together identified in 1.8% of unrelated NF1 individuals. About 25% (95% confidence interval: 20.5-31.2%) of individuals heterozygous for a pathogenic NF1 p.Met1149, p.Arg1276, or p.Lys1423 missense variant had a Noonan-like phenotype, which is significantly more compared with the "classic" NF1-affected cohorts (all p < .0001). Furthermore, p.Arg1276 and p.Lys1423 pathogenic missense variants were associated with a high prevalence of cardiovascular abnormalities, including pulmonic stenosis (all p < .0001), while p.Arg1276 variants had a high prevalence of symptomatic spinal neurofibromas (p < .0001) compared with "classic" NF1-affected cohorts. However, p.Met1149-positive individuals had a mild phenotype, characterized mainly by pigmentary manifestations without externally visible plexiform neurofibromas, symptomatic spinal neurofibromas or symptomatic optic pathway gliomas. As up to 0.4% of unrelated individuals in the UAB cohort carries a p.Met1149 missense variant, this finding will contribute to more accurate stratification of a significant number of NF1 individuals. Although clinically relevant genotype-phenotype correlations are rare in NF1, each affecting only a small percentage of individuals, together they impact counseling and management of a significant number of the NF1 population.

Aims: To obtain the normal ranges for 2D echocardiographic (2DE) indices of myocardial work (MW) from a large group of healthy volunteers over a wide range of ages and gender. Methods and results: A total of 226 (85 men, mean age: 45 ± 13 years) healthy subjects were enrolled at 22 collaborating institutions of the Normal Reference Ranges for Echocardiography (NORRE) study. Global work index (GWI), global constructive work (GCW), global work waste (GWW), and global work efficiency (GWE) were estimated from left ventricle (LV) pressure-strain loops. Peak LV systolic pressure was non-invasively derived from brachial artery cuff pressure. The lowest values of MW indices in men and women were 1270 mmHg% and 1310 mmHg% for GWI, 1650 mmHg% and 1544 mmHg% for GCW, and 90% and 91% for GWE, respectively. The highest value for GWW was 238 mmHg% in men and 239 mmHg% in women. Men had significant lower values of GWE and higher values of GWW. GWI and GCW significantly increased with age in women. Conclusion: The NORRE study provides useful 2DE reference ranges for novel indices of non-invasive MW.

We sought to assess functional capacity in recently diagnosed untreated hypertensive patients with different 24-hour blood pressure (BP) patterns (dipping, non-dipping, extreme dipping, and reverse dipping). This cross-sectional study involved 164 untreated hypertensive patients who underwent 24-hour ambulatory BP monitoring and cardiopulmonary exercise testing. Our findings showed that 24-hour and daytime BP values did not differ between four groups. Nighttime BP significantly and gradually increased from extreme dippers to reverse dippers. There was no significant difference in BPs at baseline and at the peak of exercise among four observed groups. Peak oxygen consumption (peak VO2) was significantly lower in reverse dippers than in dippers and extreme dippers. Heart rate recovery was significantly lower among reverse dippers than in dippers and extreme dippers. Ventilation/carbon dioxide slope (VE/VCO2) was significantly higher in reverse dippers and non-dippers in comparison with dippers and extreme dippers. Non-dipping BP pattern (non-dippers and reverse dippers together) was independently and negatively associated lower heart rate recovery in the first minute and peak VO2. Reverse dipping BP pattern was independently associated not only with heart rate recovery in the first minute and peak VO2, but also with VE/VCO2. In conclusion, untreated hypertensive patients with reverse dipping BP patterns showed significantly worse functional capacity than those with dipping and extreme dipping BP patterns. Circadian BP rhythm is related with functional capacity and should be taken into account in the risk assessment of hypertensive patients.

Vaccination against communicable diseases is crucial for disease prevention, but this practice poses challenges to healthcare professionals in patients with haemophilia. Poor knowledge of the vaccination requirements for these patients and safety concerns often result in vaccination delay or avoidance. In order to address this issue, a panel of 11 Italian haemophilia and immunization experts conducted a Delphi consensus process to identify the main concerns regarding the safe use of vaccines in patients with haemophilia. The consensus was based on a literature search of the available evidence, which was used by the experts to design 27 consensus statements. A group of clinicians then rated these statements using the 5-point Likert-type scale (1 = strongly disagree; 5 = strongly agree). The main issues identified by the expert panel included vaccination schedule for haemophilic patients; protocol and optimal route of vaccine administration; vaccination of haemophilic patients with antibodies inhibiting coagulation factor VIII (inhibitors); and vaccination and risk of inhibitor development. This manuscript discusses these controversial areas in detail supported by the available literature evidence and provides evidence- and consensus-based recommendations. Overall, participants agreed on most statements, except those addressing the potential role of vaccination in inhibitor formation. Participants agreed that patients with haemophilia should receive vaccinations according to the institutional schedule for individuals without bleeding disorders; however, vaccination of patients with haemophilia requires comprehensive planning, taking into account disease severity, type and route of vaccination, and bleeding risk. Data also suggest vaccination timing does not need to take into consideration when the patient received factor VIII replacement.