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Access status: Open Access ,
Gold‐Stabilized Copper Enables Anodic Hydrogen Evolution for Ultralow‐Voltage CO‐to‐Ethylene Electrolysis
(Wiley, 2026-08-09) Park, Sungjin; Liu, Hengzhou; Shin, Heejong; Abbas, Hafiz Ghulam; Bonnenfant, Loann; Xie, Ke; Lee, Hyeon Seok; Arabyarmohammadi, Fatemeh; Huang, Jianan Erick; Papangelakis, Panos; Wang, Peiying; Zeraati, Ali Shayesteh; Kim, Jiheon; Dorakhan, Roham; Sinton, David; Liu, Xiaopeng; Li, Wenzhen; Lee, Byoung‐hoon; Sargent, Edward H.
Electrochemical upgrading from CO2 and CO to ethylene has typically been coupled with the oxygen evolution reaction (OER), whose high standard reduction potential leads to full-cell voltages above 2.2 V at 200 mA/cm2. Here we explored an alternative anodic reaction, where furfural is oxidized to furoic acid, a reaction having a low onset potential (E0 ≈ 0.05 V vs. RHE), and which reaction is accompanied by the evolution of H2: an anodic hydrogen evolution reaction (a-HER). In early experiments, copper oxide as a-HER catalyst exhibit limited stability (< 10 min) and activity (80 mA/cm2 at 0.8 Vcell). We found, using operando spectroscopy, that hydroxide forms on the surface of copper and deactivates the desired a-HER process. When we screened candidate metal dopants, we found the best to be Au, for it served to stabilize the Cu surface, enablinained a-HER: 260 mA cm−2 at 0.8 Vcell and stable operation for 16 h. Integrated into a paired CO-to-ethylene electrolyzer, this delivered 0.92 Vfullcell at 400 mA cm−2, required 40 GJ electricity per ton of ethylene, and co-produced 460 kg H2 per ton ethylene. To enable comparison with CO2-to-ethylene reports, which require an additional CO2-to-CO step, we estimate ∼ 69 GJ/tonC2H4.
Access status: Open Access ,
Metal pre-intercalation promotes water-mediated proton-coupled electron transfer in layered δ-MnO2 for aqueous pseudocapacitive energy storage
(Springer Science and Business Media LLC, 2026-07-28) Ze, Huajie; Song, Yongkwon; Wang, Xijun; Ni, Weiyan; Hu, Xiaobing; Huang, Jianan Erick; Liu, Zeyan; Liu, Hengzhou; Li, Xiao-Yan; Snurr, Randall Q.; Hersam, Mark C.; Xie, Ke; Sargent, Edward H.
The charge storage capacitance of δ-MnO2-based pseudocapacitors stems from a combination of bulk cation intercalation/deintercalation and surface proton chemisorption/desorption. Here, we investigate the mechanistic origins of the enhanced capacitance in δ-MnO2 with pre-intercalated Cu2+. To this end, we synthesize Au-core/δ-MnO2-shell nanostructures with and without Cu2+ pre-intercalation, enabling real-time in situ spectroscopic monitoring of structure-function relationships during electrochemical cycling. Transition metal pre-intercalation preserves interlayer-confined water, which in turn supports proton-coupled charge storage via the reversible reaction of MnO2 + H2O + e- ⇌ MnOOH + OH-. This confined water forms a hydrogen-bonded network that lowers the energy barrier for proton transport within the interlayer space. Similar mechanistic transition is also evident in δ-MnO2 systems pre-intercalated with other transition metal ions, such as Co2+ and Mg2+. By tuning the MnO2 shell thickness, we decouple the relative contributions of proton- and cation-driven processes, revealing that proton intercalation delivers a markedly higher specific capacitance than cation intercalation. Electrolyte-dependent studies further reveal that Cu2+ pre-intercalation promotes OH- transport within the interlayer space while preserving proton accessibility at active sites. These findings suggest that proton-coupled transport may offer further increases in charge storage performance in pseudocapacitors.
Access status: Open Access ,
External Beam Breast and Chest Wall Re-Irradiation Following Resection of Ipsilateral Breast Cancer Recurrence: Dose–Toxicity Relationships and Long-Term Oncologic Outcomes
(2026-09-05) Ghosh, Suman; Soliman, Hany; Chow, Edward; Chen, Hanbo; Leung, Eric; Karam, Irene; Rakovitch, Eileen; Safavi, Amir H.; Vesprini, Danny; Czarnota, Gregory J.
Background/Objectives: Breast/chest wall (B/CW) re-irradiation (reRT) is approached cautiously because of concerns regarding late toxicity and uncertain benefit. Contemporary data on mature toxicity and oncologic outcomes after external beam photon reRT are limited. Methods: This retrospective cohort included 113 consecutive patients who completed reRT after resection of locoregionally recurrent breast cancer between 2010 and 2024. The primary endpoint was cumulative incidence of late grade ≥ 2 CTCAE toxicity, analyzed using competing-risks methods. Secondary endpoints were locoregional recurrence-free survival (LRRFS) and local failure (LF), assessed using Kaplan–Meier, Cox regression, and Fine–Gray modeling. Results: Median age at reRT was 66 years. Most recurrences were early-stage (72.6%) and hormone receptor-positive (68.1%). Median cumulative EQD2 was 94.9 Gy, and 25.7% received IMRT. At 67.1 months’ median follow-up, 5-year cumulative incidences of grade ≥ 2 and grade 3 toxicity were 35.4% (95% CI, 25.6–45.1) and 3.9% (95% CI, 0.1–7.8), respectively. Higher cumulative EQD2 predicted grade ≥ 2 toxicity (SHR, 1.94 per 10 Gy; p < 0.001) and grade 3 toxicity (SHR, 4.32 per 10 Gy; p < 0.001). Longer interval between radiotherapy courses (p = 0.029) and IMRT (SHR, 0.40; p = 0.005) were associated with lower grade ≥ 2 toxicity. Five-year LRRFS was 84.2% (95% CI, 76.7–92.4), and LF was 6.8%. Advanced-stage disease and second or subsequent recurrence predicted inferior LRRFS. Partial B/CW reRT did not compromise disease control in early-stage recurrences. Conclusions: Adjuvant breast and chest wall re-irradiation using external photons achieved durable locoregional control with low rates of severe late toxicity in one of the largest reported cohorts. These findings support individualized curative-intent reRT guided by cumulative dose, technique, and recurrence risk.
Access status: Open Access ,
Differences in Chronic Pulmonary Embolism Burden in Chronic Thromboembolic Disease with and Without Pulmonary Hypertension
(2026-09-05) McQuade, Colin; Davoudi, Dayana; Lajkosz, Katherine; Donahoe, Laura; Granton, John; Perrot, Marc de; McInnis, Micheal
Background: Chronic thromboembolic disease is a recognised sequela of acute pulmonary embolism and may occur with or without pulmonary hypertension. The purpose of this study was to evaluate differences in chronic thromboembolic burden, lesion type, and distribution between chronic thromboembolic pulmonary disease without pulmonary hypertension (CTEPD) and chronic thromboembolic pulmonary hypertension (CTEPH). Methods: This retrospective single-centre study included patients with CTEPD or CTEPH by right heart catheterisation using 2022 ESC/ERS criteria between 2021 and 2022. Two CTEPH patients were randomly selected per CTEPD patient. CTPA studies were reviewed by a blinded thoracic radiologist, assessing 32 pulmonary vessels from the main to segmental arteries for chronic thromboembolic lesions. Groups were compared by disease distribution, most proximal lesion level, Qanadli obstruction index, lesion type, and location. Exploratory receiver operating characteristic (ROC) analysis assessed discriminatory performance. Results: The 44 CTEPD and 88 CTEPH patients included had no differences in age, BMI, or sex. CTEPH patients had shorter six-minute walk distance (p = 0.001), greater right ventricular dilation/dysfunction (p < 0.001), and lower prevalence of deep vein thrombosis (p = 0.03). CTPA identified more lesions in CTEPH (21.2 vs. 10.0 lesions/case, p < 0.001) across more lobes (4.8 vs. 3.4, p < 0.001), with more proximal main/lobar disease (p < 0.001). CT obstruction index was 51% in CTEPH and 26% in CTEPD (p < 0.001). Total lesion number best discriminated CTEPH from CTEPD (AUC 0.91; optimal cutoff, 16 lesions). Conclusions: CTEPH demonstrates a greater, more diffuse, and more proximal chronic thromboembolic lesion burden on CTPA than CTEPD.
Access status: Open Access ,
Gold Nanoparticle-Mediated DNA Damage Under FLASH Electron-Beam Irradiation: A Monte Carlo Study
(2026-09-04) Kim, Chloe Doen; Chow, James C. L.
FLASH radiotherapy, which delivers radiation at ultrahigh dose rates (UHDRs) exceeding 40 Gy/s, has attracted considerable attention because of its potential to spare normal tissues while maintaining tumour control. Gold nanoparticles (GNPs) are promising radiosensitizers that enhance radiation-induced biological effects through increased production of reactive oxygen species (ROS) and subsequent DNA damage. However, the influence of GNPs on DNA damage under FLASH irradiation remains poorly understood. In this study, Geant4-DNA Monte Carlo simulations were performed to investigate the effects of GNP size and dose rate on DNA damage during UHDR electron-beam irradiation. DNA damage was quantified through both direct and indirect mechanisms based on energy deposition in DNA backbone segments and interactions between radiation-induced radical species and DNA, and was evaluated relative to equivalent water nanoparticle (WNP) controls. The results demonstrated a dose rate-dependent reduction in both relative single-strand breaks (RSSBs) and relative double-strand breaks (RDSBs) arising from direct and indirect DNA damage mechanisms. For the 10 keV monoenergetic model condition, the 10 nm GNP produced the greatest radiosensitization among the particle sizes investigated, with the matched GNP/WNP analysis showing a maximum 5-fold enhancement in direct SSB yields. In contrast, substantially weaker GNP-specific enhancement and no comparable size-dependent effect were observed at 1 MeV. These findings demonstrate that GNP-mediated radiosensitization depends on both nanoparticle size and electron energy under the irradiation conditions investigated. The greater enhancement observed for the 10 nm GNP at 10 keV should therefore not be interpreted as identifying a universally optimal GNP size for FLASH radiotherapy.