Spanish and Catalan Versions of the eHealth Literacy Questionnaire: Translation, Cross-Cultural Adaptation, and Validation Study.

BACKGROUND: The rise of digital health services, especially following the outbreak of COVID-19, has led to a need for health literacy policies that respond to people's needs. Spain is a country with a highly developed digital health infrastructure, but there are currently no tools available to measure digital health literacy fully. A well-thought-through questionnaire with strong psychometric properties such as the eHealth Literacy Questionnaire (eHLQ) is important to assess people's eHealth literacy levels, especially in the context of a fast-growing field such as digital health. OBJECTIVE: This study aims to adapt the eHLQ and gather evidence of its psychometric quality in 2 of Spain's official languages: Spanish and Catalan. METHODS: A systematic cultural adaptation process was followed. Data from Spanish-speaking (n=400) and Catalan-speaking (n=400) people were collected. Confirmatory factor analysis was used to confirm the previously established factor structure. For reliability, the Cronbach α and categorical ω were obtained for every subscale. Evidence of convergent and discriminant validity was provided through the correlation with the total score of the eHealth Literacy Scale. Evidence based on relations to other variables was evaluated by examining extreme values for educational level, socioeconomic level, and use of technology variables. RESULTS: Regarding the confirmatory factor analysis, the 7-factor correlated model and the 7 one-factor models had adequate goodness-of-fit indexes for both Spanish and Catalan. Moreover, measurement invariance was established between the Spanish and Catalan versions. Reliability estimates were considered adequate as all the scales in both versions had values of >0.80. For convergent and discriminant validity evidence, the eHealth Literacy Scale showed moderate correlation with eHLQ scales in both versions (Spanish: range 0.57-0.76 and P<.001; Catalan: range 0.41-0.64 and P<.001). According to the relationship with external variables, all the eHLQ scales in both languages could discriminate between the maximum and minimum categories in level of education, socioeconomic level, and level of technology use. CONCLUSIONS: The Spanish and Catalan versions of the eHLQ appear to be psychometrically sound questionnaires for assessing digital health literacy. They could both be useful tools in Spain and Catalonia for researchers, policy makers, and health service managers to explore people's needs, skills, and competencies and provide interesting insights into their interactions and engagement regarding their own experiences with digital health services, especially in the context of digital health growth in Spain.

Structural and Reactivity Effects of Secondary Metal Doping into Iron-Nitrogen-Carbon Catalysts for Oxygen Electroreduction.

While improved activity was recently reported for bimetallic iron-metal-nitrogen-carbon (FeMNC) catalysts for the oxygen reduction reaction (ORR) in acid medium, the nature of active sites and interactions between the two metals are poorly understood. Here, FeSnNC and FeCoNC catalysts were structurally and catalytically compared to their parent FeNC and SnNC catalysts. While CO cryo-chemisorption revealed a twice lower site density of M-Nx sites for FeSnNC and FeCoNC relative to FeNC and SnNC, the mass activity of both bimetallic catalysts is 50-100% higher than that of FeNC due to a larger turnover frequency in the bimetallic catalysts. Electron microscopy and X-ray absorption spectroscopy identified the coexistence of Fe-Nx and Sn-Nx or Co-Nx sites, while no evidence was found for binuclear Fe-M-Nx sites. 57Fe Mössbauer spectroscopy revealed that the bimetallic catalysts feature a higher D1/D2 ratio of the spectral signatures assigned to two distinct Fe-Nx sites, relative to the FeNC parent catalyst. Thus, the addition of the secondary metal favored the formation of D1 sites, associated with the higher turnover frequency.

Regulating Catalytic Properties and Thermal Stability of Pt and PtCo Intermetallic Fuel-Cell Catalysts via Strong Coupling Effects between Single-Metal Site-Rich Carbon and Pt.

Developing low platinum-group-metal (PGM) catalysts for the oxygen reduction reaction (ORR) in proton-exchange membrane fuel cells (PEMFCs) for heavy-duty vehicles (HDVs) remains a great challenge due to the highly demanded power density and long-term durability. This work explores the possible synergistic effect between single Mn site-rich carbon (MnSA-NC) and Pt nanoparticles, aiming to improve intrinsic activity and stability of PGM catalysts. Density functional theory (DFT) calculations predicted a strong coupling effect between Pt and MnN4 sites in the carbon support, strengthening their interactions to immobilize Pt nanoparticles during the ORR. The adjacent MnN4 sites weaken oxygen adsorption at Pt to enhance intrinsic activity. Well-dispersed Pt (2.1 nm) and ordered L12-Pt3Co nanoparticles (3.3 nm) were retained on the MnSA-NC support after indispensable high-temperature annealing up to 800 °C, suggesting enhanced thermal stability. Both PGM catalysts were thoroughly studied in membrane electrode assemblies (MEAs), showing compelling performance and durability. The Pt@MnSA-NC catalyst achieved a mass activity (MA) of 0.63 A mgPt-1 at 0.9 ViR-free and maintained 78% of its initial performance after a 30,000-cycle accelerated stress test (AST). The L12-Pt3Co@MnSA-NC catalyst accomplished a much higher MA of 0.91 A mgPt-1 and a current density of 1.63 A cm-2 at 0.7 V under traditional light-duty vehicle (LDV) H2-air conditions (150 kPaabs and 0.10 mgPt cm-2). Furthermore, the same catalyst in an HDV MEA (250 kPaabs and 0.20 mgPt cm-2) delivered 1.75 A cm-2 at 0.7 V, only losing 18% performance after 90,000 cycles of the AST, demonstrating great potential to meet the DOE targets.

Pt Particle Size Affects Both the Charge Separation and Water Reduction Efficiencies of CdS-Pt Nanorod Photocatalysts for Light Driven H2 Generation.

Decreasing the metal catalyst size into nanoclusters or even single atom is an emerging direction of developing more efficient and cost-effective photocatalytic systems. Because the catalyst particle size affects both the catalyst activity and light driven charge separation efficiency, their effects on the overall photocatalytic efficiency are still poorly understood. Herein, using a well-defined semiconductor-metal heterostructure with Pt nanoparticle catalysts selectively grown on the apexes of CdS nanorods (NRs), we study the effect of the Pt catalyst size on light driven H2 generation quantum efficiency (QEH2). With the increase of the Pt catalyst size from 0.7 ± 0.3 to 3.0 ± 0.8 nm, the QEH2 of CdS-Pt increases from 0.5 ± 0.2% to 38.3 ± 5.1%, by nearly 2 orders of magnitude. Transient absorption spectroscopy measurement reveals that the electron transfer rate from the CdS NR to the Pt tip increases with the Pt diameter following a scaling law of d5.6, giving rise to the increase of electron transfer efficiency at larger Pt sizes. The observed trend can be understood by a simplified kinetic model that assumes the overall efficiency is the product of the quantum efficiencies of charge separation (including hole transfer, electron transfer, and hole scavenging) and water reduction steps, and for CdS-Pt NRs, the quantum efficiencies of electron transfer and water reduction steps increase with the Pt sizes. Our findings suggest the importance of improving the quantum efficiencies of both charge separation and catalysis in designing efficient semiconductor-metal hybrid photocatalysts, especially in the regime of small metal particle sizes.

Molecular Catalyst Synthesis Strategies to Prepare Atomically Dispersed Fe-N-C Heterogeneous Catalysts.

We report a strategy to integrate atomically dispersed iron within a heterogeneous nitrogen-doped carbon (N-C) support, inspired by routes for metalation of molecular macrocyclic iron complexes. The N-C support, derived from pyrolysis of a ZIF-8 metal-organic framework, is metalated via solution-phase reaction with FeCl2 and tributyl amine, as a Brønsted base, at 150 °C. Fe active sites are characterized by 57Fe Mössbauer spectroscopy and aberration-corrected scanning transmission electron microscopy. The site density can be increased by selective removal of Zn2+ ions from the N-C support prior to metalation, resembling the transmetalation strategy commonly employed for the preparation of molecular Fe-macrocycles. The utility of this approach is validated by the higher catalytic rates (per total Fe) of these materials relative to established Fe-N-C catalysts, benchmarked using an aerobic oxidation reaction.

Tuning Catalyst Activation and Utilization Via Controlled Electrode Patterning for Low-Loading and High-Efficiency Water Electrolyzers.

An anode electrode concept of thin catalyst-coated liquid/gas diffusion layers (CCLGDLs), by integrating Ir catalysts with Ti thin tunable LGDLs with facile electroplating in proton exchange membrane electrolyzer cells (PEMECs), is proposed. The CCLGDL design with only 0.08 mgIr cm-2 can achieve comparative cell performances to the conventional commercial electrode design, saving ≈97% Ir catalyst and augmenting a catalyst utilization to ≈24 times. CCLGDLs with regulated patterns enable insight into how pattern morphology impacts reaction kinetics and catalyst utilization in PEMECs. A specially designed two-sided transparent reaction-visible cell assists the in situ visualization of the PEM/electrode reaction interface for the first time. Oxygen gas is observed accumulating at the reaction interface, limiting the active area and increasing the cell impedances. It is demonstrated that mass transport in PEMECs can be modified by tuning CCLGDL patterns, thus improving the catalyst activation and utilization. The CCLGDL concept promises a future electrode design strategy with a simplified fabrication process and enhanced catalyst utilization. Furthermore, the CCLGDL concept also shows great potential in being a powerful tool for in situ reaction interface research in PEMECs and other energy conversion devices with solid polymer electrolytes.

Chemical vapour deposition of Fe-N-C oxygen reduction catalysts with full utilization of dense Fe-N4 sites.

Replacing scarce and expensive platinum (Pt) with metal-nitrogen-carbon (M-N-C) catalysts for the oxygen reduction reaction in proton exchange membrane fuel cells has largely been impeded by the low oxygen reduction reaction activity of M-N-C due to low active site density and site utilization. Herein, we overcome these limits by implementing chemical vapour deposition to synthesize Fe-N-C by flowing iron chloride vapour over a Zn-N-C substrate at 750 °C, leading to high-temperature trans-metalation of Zn-N4 sites into Fe-N4 sites. Characterization by multiple techniques shows that all Fe-N4 sites formed via this approach are gas-phase and electrochemically accessible. As a result, the Fe-N-C catalyst has an active site density of 1.92 × 1020 sites per gram with 100% site utilization. This catalyst delivers an unprecedented oxygen reduction reaction activity of 33 mA cm-2 at 0.90 V (iR-corrected; i, current; R, resistance) in a H2-O2 proton exchange membrane fuel cell at 1.0 bar and 80 °C.

Harvesting Sub-Bandgap IR Photons by Photothermionic Hot Electron Transfer in a Plasmonic p-n Junction.

Plasmonic semiconductors are an emerging class of low-cost plasmonic materials, and the presence of a bandgap and band-bending in these materials offer new opportunities to overcome some of the limitations of plasmonic metals. Here, we demonstrate that in a plasmonic p-n heterojunction (Cu2-xSe-CdSe) the near-IR excitation (1.1 eV) of the hole plasmon in the p-Cu2-xSe phase results in rapid hot electron transfer to n-CdSe, with an energy 2.2 eV above the Fermi level. This hot electron generation and energy upconversion process can be well-described by a photothermionic mechanism, where the presence of a bandgap in p-Cu2-xSe facilitates the generation of energetic photothermal electrons. The lifetime of the transferred electrons in Cu2-xSe-CdSe can reach ∼130 ps, which is nearly 100× longer than that of its metal-semiconductor counterpart. This result demonstrates a novel approach for harvesting the sub-bandgap near IR photons using plasmonic p-n junctions and the potential advantages of plasmonic semiconductors for hot carrier-based devices.

Synthesis of Novel Phases in Si Nanowires Using Diamond Anvil Cells at High Pressures and Temperatures.

Silicon has several technologically promising allotropes that are formed via high-pressure synthesis. One of these phases (hd) has been predicted to have a direct band gap under tensile strain, whereas other (r8 and bc8) phases are predicted to have narrow band gaps and good absorption across the solar spectrum. Pure volumes of these phases cannot be made using conventional nanowire growth techniques. In this work, Si nanowires were compressed up to ∼20 GPa and then decompressed using a diamond anvil cell in the temperature range of 25-165 °C. It was found that at intermediate temperatures, near-phase-pure bc8-Si nanowires were produced, whereas amorphous Si (a-Si) dominated at lower temperatures, and a direct transformation to the diamond cubic phase (dc-Si) occurred at higher temperatures under compression. Thus this study has opened up a new pressure-temperature pathway for the synthesis of novel Si nanowires consisting of designed phase components with transformative properties.

Covalent Organic Framework (COF) Derived Ni-N-C Catalysts for Electrochemical CO2 Reduction: Unraveling Fundamental Kinetic and Structural Parameters of the Active Sites.

Electrochemical CO2 reduction is a potential approach to convert CO2 into valuable chemicals using electricity as feedstock. Abundant and affordable catalyst materials are needed to upscale this process in a sustainable manner. Nickel-nitrogen-doped carbon (Ni-N-C) is an efficient catalyst for CO2 reduction to CO, and the single-site Ni-Nx motif is believed to be the active site. However, critical metrics for its catalytic activity, such as active site density and intrinsic turnover frequency, so far lack systematic discussion. In this work, we prepared a set of covalent organic framework (COF)-derived Ni-N-C catalysts, for which the Ni-Nx content could be adjusted by the pyrolysis temperature. The combination of high-angle annular dark-field scanning transmission electron microscopy and extended X-ray absorption fine structure evidenced the presence of Ni single-sites, and quantitative X-ray photoemission addressed the relation between active site density and turnover frequency.

Slow Auger Recombination of Trapped Excitons Enables Efficient Multiple Electron Transfer in CdS-Pt Nanorod Heterostructures.

Solar-to-fuel conversion reaction often requires multiple proton-coupled electron transfer (PCET) processes powered by the energetic electrons and/or holes generated by the absorption of multiple photons. The effective coupling of multiple electron transfer from the light absorber with the multiple PCET reactions at the catalytic center is one of the key challenges in efficient and selective conversion of solar energy to chemical fuels. In this paper, we examine the dynamics of multiple electron transfer in quantum confined CdS nanorods with a Pt tip, in which the CdS rod functions as the light absorber and the Pt tip the catalytic center. By excitation-fluence-dependent transient absorption spectroscopic measurements, we show that the multiexciton Auger recombination rate in CdS rods follows a carrier-collision model, knA = n2(n - 1)/4k2A, with a biexciton lifetime (1/k2A) of 2.0 ± 0.2 ns. In CdS-Pt nanorods, electron transfer kinetics from the CdS conduction band edge to the Pt show negligible dependence on the excitation fluence, occurring with a half-life time of 5.6 ± 0.6 ps. The efficiency of multiple exciton dissociation by multiple electron transfer to Pt decreases from 100% in biexciton states to ∼41% at 22 exciton state due to the competition with Auger recombination. The half-lifetime of the n-charge separated state recombination (with n electrons in the Pt and n holes in the CdS) decreases from 10 µs in the single charge separated state to 42 ns in nine charge separated states. Our findings suggest the possibility of driving multielectron photocatalytic reactions under intense illumination and controlling product selectivity through multielectron transfer.

P-block single-metal-site tin/nitrogen-doped carbon fuel cell cathode catalyst for oxygen reduction reaction.

This contribution reports the discovery and analysis of a p-block Sn-based catalyst for the electroreduction of molecular oxygen in acidic conditions at fuel cell cathodes; the catalyst is free of platinum-group metals and contains single-metal-atom actives sites coordinated by nitrogen. The prepared SnNC catalysts meet and exceed state-of-the-art FeNC catalysts in terms of intrinsic catalytic turn-over frequency and hydrogen-air fuel cell power density. The SnNC-NH3 catalysts displayed a 40-50% higher current density than FeNC-NH3 at cell voltages below 0.7 V. Additional benefits include a highly favourable selectivity for the four-electron reduction pathway and a Fenton-inactive character of Sn. A range of analytical techniques combined with density functional theory calculations indicate that stannic Sn(IV)Nx single-metal sites with moderate oxygen chemisorption properties and low pyridinic N coordination numbers act as catalytically active moieties. The superior proton-exchange membrane fuel cell performance of SnNC cathode catalysts under realistic, hydrogen-air fuel cell conditions, particularly after NH3 activation treatment, makes them a promising alternative to today's state-of-the-art Fe-based catalysts.

Impact of the first surge of the COVID-19 pandemic on a tertiary referral centre for kidney cancer.

OBJECTIVE: To analyse the impact of the COVID-19 pandemic on a centralized specialist kidney cancer care pathway. MATERIALS AND METHODS: We conducted a retrospective analysis of patient and pathway characteristics including prioritization strategies at the Specialist Centre for Kidney Cancer located at the Royal Free London NHS Foundation Trust (RFH) before and during the surge of COVID-19. RESULTS: On 18 March 2020 all elective surgery was halted at RFH to redeploy resources and staff for the COVID-19 surge. Prioritizing of patients according to European Association of Urology guidance was introduced. Clinics and the specialist multidisciplinary team (SMDT) meetings were maintained with physical distancing, kidney surgery was moved to a COVID-protected site, and infection prevention measurements were enforced. During the 7 weeks of lockdown (23 March to 10 May 2020), 234 cases were discussed at the SMDT meetings, 53% compared to the 446 cases discussed in the 7 weeks pre-lockdown. The reduction in referrals was more pronounced for small and asymptomatic renal masses. Of 62 low-priority cancer patients, 27 (43.5%) were deferred. Only one (4%) COVID-19 infection occurred postoperatively, and the patient made a full recovery. No increase in clinical or pathological upstaging could be detected in patients who underwent deferred surgery compared to pre-COVID practice. CONCLUSION: The first surge of the COVID-19 pandemic severely impacted diagnosis, referral and treatment of kidney cancer at a tertiary referral centre. With a policy of prioritization and COVID-protected pathways, capacity for time-sensitive oncological interventions was maintained and no immediate clinical harm was observed.

Growth and renal function dynamics of renal oncocytomas in patients on active surveillance.

OBJECTIVES: To study the natural history of renal oncocytomas and address indications for intervention by determining how growth is associated with renal function over time, the reasons for surgery and ablation, and disease-specific survival. PATIENTS AND METHODS: The study was conducted in a retrospective cohort of consecutive patients with renal oncocytoma on active surveillance reviewed at the Specialist Centre for Kidney Cancer at the Royal Free London NHS Foundation Trust (2012 to 2019). Comparison between groups was performed using Mann-Whitney U-tests and chi-squared tests. A mixed-effects model with a random intercept for patient was used to study the longitudinal association between tumour size and estimated glomerular filtration rate (eGFR). RESULTS: Longitudinal data from 98 patients with 101 lesions were analysed. Most patients were men (68.3%) and the median (interquartile range [IQR]) age was 69 (13) years. The median (IQR) follow-up was 29 (26) months. Most lesions were small renal masses, and 24% measured over 4 cm. Over half (64.4%) grew at a median (IQR) rate of 2 (4) mm per year. No association was observed between tumour size and eGFR over time (P = 0.871). Nine lesions (8.9%) were subsequently treated. Two deaths were reported, neither were related to the diagnosis of renal oncocytoma. CONCLUSION: Natural history data from the largest active surveillance cohort of renal oncocytomas to date show that renal function does not seem to be negatively impacted by growing oncocytomas, and confirms clinical outcomes are excellent after a median follow-up of over 2 years. Active surveillance should be considered the 'gold standard' management of renal oncocytomas up to 7cm.

Pattern, timing and predictors of recurrence after surgical resection of chromophobe renal cell carcinoma.

PURPOSE: Currently there are no specific guidelines for the post-operative follow-up of chromophobe renal cell carcinoma (chRCC). We aimed to evaluate the pattern, location and timing of recurrence after surgery for non-metastatic chRCC and establish predictors of recurrence and cancer-specific death. METHODS: Retrospective analysis of consecutive surgically treated non-metastatic chRCC cases from the Royal Free London NHS Foundation Trust (UK, 2015-2019) and the international collaborative database RECUR (15 institutes, 2006-2011). Kaplan-Meier curves were plotted. The association between variables of interest and outcomes were analysed using univariate and multivariate Cox proportional hazards regression models with shared frailty for data source. RESULTS: 295 patients were identified. Median follow-up was 58 months. The five and ten-year recurrence-free survival rates were 94.3% and 89.2%. Seventeen patients (5.7%) developed recurrent disease, 13 (76.5%) with distant metastases. 54% of metastatic disease diagnoses involved a single organ, most commonly the bone. Early recurrence (< 24 months) was observed in 8 cases, all staged ≥ pT2b. 30 deaths occurred, of which 11 were attributed to chRCC. Sarcomatoid differentiation was rare (n = 4) but associated with recurrence and cancer-specific death on univariate analysis. On multivariate analysis, UICC/AJCC T-stage ≥ pT2b, presence of coagulative necrosis, and positive surgical margins were predictors of recurrence and cancer-specific death. CONCLUSION: Recurrence and death after surgically resected chRCC are rare. For completely excised lesions ≤ pT2a without coagulative necrosis or sarcomatoid features, prognosis is excellent. These patients should be reassured and follow-up intensity curtailed.

Efficient Hot Electron Transfer from Small Au Nanoparticles.

Many important chemical transformations enabled by plasmonic hot carrier photocatalysis have been reported, although their efficiencies are often too low for practical applications. We examine how the efficiency of plasmon-induced hot electron transfer depends on the Au particle size in Au-tipped CdS nanorods. We show that with decreasing Au size, the plasmon width increases due to enhanced surface damping contributions. The excitation of Au nanoparticles leads to an instrument response time-limited ultrafast hot electron transfer process to CdS (≪140 fs). The quantum efficiency of this process increases from ∼1% to ∼18% as the particle size decreases from 5.5 ± 1.1 to 1.6 ± 0.5 nm due to both enhanced hot electron generation and transfer efficiencies in small Au particles. Our finding suggests that decreasing plasmonic particle size is an effective approach for improving plasmon-induced hot carrier transfer efficiency and provides important insight for the rational improvement of plasmonic hot carrier-based devices.

Bridging Thermal Catalysis and Electrocatalysis: Catalyzing CO2 Conversion with Carbon-Based Materials.

Understanding the differences between reactions driven by elevated temperature or electric potential remains challenging, largely due to materials incompatibilities between thermal catalytic and electrocatalytic environments. We show that Ni, N-doped carbon (NiPACN), an electrocatalyst for the reduction of CO2 to CO (CO2 R), can also selectively catalyze thermal CO2 to CO via the reverse water gas shift (RWGS) representing a direct analogy between catalytic phenomena across the two reaction environments. Advanced characterization techniques reveal that NiPACN likely facilitates RWGS on dispersed Ni sites in agreement with CO2 R active site studies. Finally, we construct a generalized reaction driving-force that includes temperature and potential and suggest that NiPACN could facilitate faster kinetics in CO2 R relative to RWGS due to lower intrinsic barriers. This report motivates further studies that quantitatively link catalytic phenomena across disparate reaction environments.

Engineering Atomically Dispersed FeN4 Active Sites for CO2 Electroreduction.

Atomically dispersed FeN4 active sites have exhibited exceptional catalytic activity and selectivity for the electrochemical CO2 reduction reaction (CO2RR) to CO. However, the understanding behind the intrinsic and morphological factors contributing to the catalytic properties of FeN4 sites is still lacking. By using a Fe-N-C model catalyst derived from the ZIF-8, we deconvoluted three key morphological and structural elements of FeN4 sites, including particle sizes of catalysts, Fe content, and Fe-N bond structures. Their respective impacts on the CO2RR were comprehensively elucidated. Engineering the particle size and Fe doping is critical to control extrinsic morphological factors of FeN4 sites for optimal porosity, electrochemically active surface areas, and the graphitization of the carbon support. In contrast, the intrinsic activity of FeN4 sites was only tunable by varying thermal activation temperatures during the formation of FeN4 sites, which impacted the length of the Fe-N bonds and the local strains. The structural evolution of Fe-N bonds was examined at the atomic level. First-principles calculations further elucidated the origin of intrinsic activity improvement associated with the optimal local strain of the Fe-N bond.

Dynamically Unveiling Metal-Nitrogen Coordination during Thermal Activation to Design High-Efficient Atomically Dispersed CoN4 Active Sites.

We elucidate the structural evolution of CoN4 sites during thermal activation by developing a zeolitic imidazolate framework (ZIF)-8-derived carbon host as an ideal model for Co2+ ion adsorption. Subsequent in situ X-ray absorption spectroscopy analysis can dynamically track the conversion from inactive Co-OH and Co-O species into active CoN4 sites. The critical transition occurs at 700 °C and becomes optimal at 900 °C, generating the highest intrinsic activity and four-electron selectivity for the oxygen reduction reaction (ORR). DFT calculations elucidate that the ORR is kinetically favored by the thermal-induced compressive strain of Co-N bonds in CoN4 active sites formed at 900 °C. Further, we developed a two-step (i.e., Co ion doping and adsorption) Co-N-C catalyst with increased CoN4 site density and optimized porosity for mass transport, and demonstrated its outstanding fuel cell performance and durability.

Safety and feasibility of early single-dose mitomycin C bladder instillation after robot-assisted radical nephroureterectomy.

OBJECTIVES: To assess the safety and feasibility of early single-dose mitomycin C (MMC) bladder instillation after robot-assisted radical nephroureterectomy (RARNU) at a tertiary kidney cancer centre. RARNU with bladder cuff excision and subsequent MMC bladder instillation to reduce recurrence risk is the 'gold standard' for high-risk upper urinary tract urothelial carcinoma (UUTUC). We adapted a RARNU technique with precise distal ureteric dissection, bladder cuff excision and watertight bladder closure. PATIENTS AND METHODS: We retrospectively reviewed all patients undergoing RARNU for UUTUC at our centre performed as a standardised transperitoneal procedure comprising of: bladder cuff excision, two-layer watertight closure and intraoperative bladder leak test; without re-docking/re-positioning of the robotic surgical system. Patient demographics, the timing of MMC instillation, adverse events (surgical and potentially MMC-related) and length of stay (LOS) were assessed according to the Clavien-Dindo classification. RESULTS: A total of 69 patients underwent a RARNU with instillation of MMC. The median (interquartile range [IQR]) age was 70 (62-78) years. The median (IQR) day of MMC instillation was 2 (1-3) days and the median (IQR) LOS was 2 (2-4) days, with urethral catheter removal on day of discharge in all cases. Only Grade I Clavien-Dindo complications occurred in seven patients (10%); five had ileus, one a wound infection and one a self-limiting delirium, all managed conservatively. No adverse events potentially related to MMC instillation were noted within 30 days postoperatively. CONCLUSION: The use of intravesical MMC instillation given in the immediate postoperative period appears feasible and safe in patients undergoing RARNU with intraoperative confirmation of a water-tight closure ensuring early catheter-free discharge, with no significant adverse events. The potential reduction in intravesical recurrence in patients receiving early MMC needs to be assessed with longitudinal follow-up studies.