Engineering the Coordination Environment of Ir Single Atoms with Surface Titanium Oxide Amorphization for Superior Chlorine Evolution Reaction.

The chlorine evolution reaction (CER) is essential for industrial Cl2 production but strongly relies on the use of dimensionally stable anode (DSA) with high-amount precious Ru/Ir oxide on a Ti substrate. For the purpose of sustainable development, precious metal decrement and performance improvement are highly desirable for the development of CER anodes. Herein, we demonstrate that surface titanium oxide amorphization is crucial to regulate the coordination environment of stabilized Ir single atoms for efficient and durable chlorine evolution of Ti monolithic anodes. Experimental and theoretical results revealed the formation of four-coordinated Ir1O4 and six-coordinated Ir1O6 sites on amorphous and crystalline titanium oxides, respectively. Interestingly, the Ir1O4 sites exhibited a superior CER performance, with a mass activity about 10 and 500 times those of the Ir1O6 counterpart and DSA, respectively. Moreover, the Ir1O4 anode displayed excellent durability for 200 h, far longer than that of its Ir1O6 counterpart (2 h). Mechanism studies showed that the unsaturated Ir in Ir1O4 was the active center for chlorine evolution, which was changed to the top-coordinated O in Ir1O6. This change of active sites greatly affected the adsorption energy of Cl species, thus accounting for their different CER activity. More importantly, the amorphous structure and restrained water dissociation of Ir1O4 synergistically prevent oxygen permeation across the Ti substrate, contributing to its long-term CER stability. This study sheds light on the importance of single-atom coordination structures in the reactivity of catalysts and offers a facile strategy to prepare highly active single-atom CER anodes via surface titanium oxide amorphization.

Characterization of the proteome of stable and unstable carotid atherosclerotic plaques using data-independent acquisition mass spectrometry.

BACKGROUND: Currently, noninvasive imaging techniques and circulating biomarkers are still insufficient to accurately assess carotid plaque stability, and an in-depth understanding of the molecular mechanisms that contribute to plaque instability is still lacking. METHODS: We established a clinical study cohort containing 182 patients with carotid artery stenosis. After screening, 39 stable and 49 unstable plaques were included in the discovery group, and quantitative proteomics analysis based on data independent acquisition was performed for these plaque samples. Additionally, 35 plaques were included in the validation group to validate the proteomics results by immunohistochemistry analysis. RESULTS: A total of 397 differentially expressed proteins were identified in stable and unstable plaques. These proteins are primarily involved in ferroptosis and lipid metabolism-related functions and pathways. Plaque validation results showed that ferroptosis- and lipid metabolism-related proteins had different expression trends in stable plaques versus unstable fibrous cap regions and lipid core regions. Ferroptosis- and lipid metabolism-related mechanisms in plaque stability were discussed. CONCLUSIONS: Our results may provide a valuable strategy for revealing the mechanisms affecting plaque stability and will facilitate the discovery of specific biomarkers to broaden the therapeutic scope.

Stroke and frailty index: a two-sample Mendelian randomisation study.

INTRODUCTION: Previous observational studies have found an increased risk of frailty in patients with stroke. However, evidence of a causal relationship between stroke and frailty is scarce. The aim of this study was to investigate the potential causal relationship between stroke and frailty index (FI). METHODS: Pooled data on stroke and debility were obtained from genome-wide association studies (GWAS).The MEGASTROKE Consortium provided data on stroke (N = 40,585), ischemic stroke (IS,N = 34,217), large-vessel atherosclerotic stroke (LAS,N = 4373), and cardioembolic stroke (CES,N = 7 193).Summary statistics for the FI were obtained from the most recent GWAS meta-analysis of UK BioBank participants and Swedish TwinGene participants of European ancestry (N = 175,226).Two-sample Mendelian randomization (MR) analyses were performed by inverse variance weighting (IVW), weighted median, MR-Egger regression, Simple mode, and Weighted mode, and heterogeneity and horizontal multiplicity of results were assessed using Cochran's Q test and MR-Egger regression intercept term test. RESULTS: The results of the current MR study showed a significant correlation between stroke gene prediction and FI (odds ratio 1.104, 95% confidence interval 1.064 - 1.144, P < 0.001). In terms of stroke subtypes, IS (odds ratio 1.081, 95% confidence interval 1.044 - 1.120, P < 0.001) and LAS (odds ratio 1.037, 95% confidence interval 1.012 - 1.062, P = 0.005). There was no causal relationship between gene-predicted CES and FI. Horizontal multidimensionality was not found in the intercept test for MR Egger regression (P > 0.05), nor in the heterogeneity test (P > 0.05). CONCLUSIONS: This study provides evidence for a causal relationship between stroke and FI and offers new insights into the genetic study of FI.

Development and validation of a risk prediction model for physical frailty in older adults who are disabled.

Physical frailty is highly prevalent among the older adults who are disabled. The aim of this study was to explore the risk factors for physical frailty in older adults who are disabled and construct a nomogram prediction model. The data source was the China Health and Retirement Longitudinal Study (CHARLS). The prediction model was validated with a cohort of 1183 older adults who are disabled. The results showed that sleep quality, depression, fatigue, and chronic disease were the best predictive factors. These factors were used to construct the nomogram model, which showed good concordance and accuracy. The prediction model yielded an Area under the curve (AUC) value of 0.760. Calibration curves showed significant agreement between the nomogram model and actual observations. Receiver operating characteristic (ROC) and Decision curve analysis (DCA) showed that the nomogram had good predictive performance. The nomogram is contributed to the screening of specific populations by clinicians.

Cobalt Single-Atom Reverse Hydrogen Spillover for Efficient Electrochemical Water Dissociation and Dechlorination.

Efficient water dissociation to atomic hydrogen (H*) with restrained recombination of H* is crucial for improving the H* utilization for electrochemical dechlorination, but is currently limited by the lack of feasible electrodes. Herein, we developed a monolithic single-atom electrode with Co single atoms anchored on the inherent oxide layer of titanium foam (Co1-TiOx/Ti), which can efficiently dissociate water into H* and simultaneously inhibit the recombination of H*, by taking advantage of the single-atom reverse hydrogen spillover effect. Experimental and theoretical calculations demonstrated that H* could be rapidly generated on the oxide layer of titanium foam, and then overflowed to the adjacent Co single atom for the reductive dechlorination. Using chloramphenicol as a proof-of-concept verification, the resulting Co1-TiOx/Ti monolithic electrode exhibited an unprecedented performance with almost 100 % dechlorination at -1.0 V, far superior to that of traditional indirect reduction-driven commercial Pd/C (52 %) and direct reduction-driven Co1-N-C (44 %). Moreover, its dechlorination rate constant of 1.64 h-1 was 4.3 and 8.6 times more active than those of Pd/C (0.38 h-1) and Co1-N-C (0.19 h-1), respectively. Our research sheds light on the rational design of hydrogen spillover-related electrocatalysts to simultaneously improve the H* generation, transfer, and utilization for environmental and energy applications.

Photochemical Acceleration of Ammonia Production by Pt1-Ptn-TiN Reduction and N2 Activation.

Stable metal nitrides (MN) are promising materials to fit the future "green" ammonia-hydrogen nexus. Either through catalysis or chemical looping, the reductive hydrogenation of MN to MN1-x is a necessary step to generate ammonia. However, encumbered by the formation of kinetically stable M-NH1─3 surface species, this reduction step remains challenging under mild conditions. Herein, we discovered that deleterious Ti-NH1─3 accumulation on TiN can be circumvented photochemically with supported single atoms and clusters of platinum (Pt1-Ptn) under N2-H2 conditions. The photochemistry of TiN selectively promoted Ti-NH formation, while Pt1-Ptn effectively transformed any formed Ti-NH into free ammonia. The generated ammonia was found to originate mainly from TiN reduction with a minor contribution from N2 activation. The knowledge accrued from this fundamental study could serve as a springboard for the development of MN materials for more efficient ammonia production to potentially disrupt the century-old fossil-powered Haber-Bosch process.

Midterm Results of a Surgeon-Modified Device to Preserve the Flow of the Internal Iliac Artery During Endovascular Repair of Aneurysm: Single-Center Experiences.

BACKGROUND: During endovascular aneurysm repair (EVAR), commercial iliac branch devices (IBDs) have become an inescapable alternative for preserving antegrade internal iliac artery (IIA) blood flow. Due to the different morphological features of aneurysms, commercial IBDs may not be suitable for all patients. Reported experience with the implantation of the new surgeon-modified IBD (sm IBD) is limited. This investigation describes the indications, efficacy, and safety of the sm IBD. METHODS: Data from consecutive elective implantations of IBDs in patients between March 2011 and May 2021 in a single center were incorporated. The sm IBDs were indicated in patients with common iliac artery aneurysms (CIAAs) and with a challenging anatomy and in those patients with or without abdominal aortic aneurysm (AAA). RESULTS: Fifteen patients (15 male, mean age 67.6 ± 7.9 years) were included. Fifteen sm IBDs were implanted in 1 procedure (100%). Fourteen (93.3%) patients had simultaneous endovascular aneurysm repair (EVAR) and 1 (6.7%) patient previously had a bilateral CIAAs repair by EVAR. The mean common iliac artery (CIA) diameter was 36.6 ± 12.5 mm. Technical success was obtained in all patients (100%). The median operation time was 189.7 ± 78.6 min, with a median fluoroscopy time of 45.3 ± 15.9 min. Axillary artery access was used in 11 (73.3%) procedures. The mean total hospital stay was 5.6 ± 2.8 days, and the postoperative follow-up was 35.4 months (range 2-120). The estimated IIA bridge stent patency at 1 year after operation was 100% and 85.7% ± 13.2% 5 years postoperatively. One (6.7%) IIA branch was occluded, and this patient remained asymptomatic. One patient (6.7%) needed reintervention, and another (6.7%) patient had type II leakage, which is currently under close surveillance. CONCLUSIONS: Using an IBD to maintain the pelvic blood flow is an effective and feasible intravascular technique, especially for patients with an abnormal iliac artery anatomy. This novel technique has similar midterm procedural success rate compared to the use of commercial IBDs. Therefore, these devices are more suitable for patients with certain anatomic challenges and can be used as an alternative treatment.

Visible Light-Driven Conversion of Carbon-Sequestrated Seawater into Stoichiometric CO and HClO with Nitrogen-Doped BiOCl Atomic Layers.

Seawater is one of the most important CO2 sequestration media for delivering value-added chemicals/fuels and active chlorine; however, this scenario is plagued by sluggish reaction rates and poor product selectivity. Herein, we first report the synthesis of nitrogen-doped BiOCl atomic layers to directly split carbon-sequestrated natural seawater (Yellow Sea, China) into stoichiometric CO (92.8 µmol h-1 ) and HClO (83.2 µmol h-1 ) under visible light with selectivities greater than 90 %. Photoelectrons enriched on the exposed BiOCl{001} facet kinetically facilitate CO2 -to-CO reduction via surface-doped nitrogen bearing Lewis basicity. Photoholes, mainly located on the lateral facets of van der Waals gaps, promote the selective oxidation of Cl- into HClO. Sequestrated CO2 also maintains the pH of seawater at around 4.2 to prevent the alkaline earth cations from precipitating. The produced HClO can effectively kill typical bacteria in the ballast water of ocean-going cargo ships, offering a green and safe way for onsite sterilization.

Single Atom Ru Monolithic Electrode for Efficient Chlorine Evolution and Nitrate Reduction.

Fabricating single-atom electrodes via atomic dispersion of active metal atoms into monolithic metal supports is of great significance to advancing the lab-to-fab translation of the electrochemical technologies. Here, we report an inherent oxide anchoring strategy to fasten ligand-free isolated Ru atoms on the amorphous layer of monolithic Ti support by regulating the electronic metal-support interactions. The prepared Ru single atom electrode exhibited exceptional electrochemical chlorine evolution activity, three orders of magnitude higher mass activity than that of commercial dimensionally stable anode, and also selectively reduced nitrate to ammonia with an unprecedented ammonia yield rate of 22.2 mol g-1 h-1 at -0.3 V. Furthermore, the Ru single atom monolithic electrode can be scaled up from 2×2 cm to 25×15 cm at least, thus demonstrating great potential for industrial electrocatalytic applications.

Hydrogen Spillover to Oxygen Vacancy of TiO2-xHy/Fe: Breaking the Scaling Relationship of Ammonia Synthesis.

Optimizing kinetic barriers of ammonia synthesis to reduce the energy intensity has recently attracted significant research interest. The motivation for the research is to discover means by which activation barriers of N2 dissociation and NHz (z = 1-2, surface intermediates) destabilization can be reduced simultaneously, that is, breaking the "scaling relationship". However, by far only a single success has been reported in 2016 based on the discovery of a strong-weak N-bonding pair: transition metals (nitrides)-LiH. Described herein is a second example that is counterintuitively founded upon a strong-strong N-bonding pair unveiled in a bifunctional nanoscale catalyst TiO2-xHy/Fe (where 0.02 ≤ x ≤ 0.03 and 0 < y < 0.03), in which hydrogen spillover (H) from Fe to cascade oxygen vacancies (OV-OV) results in the trapped form of OV-H on the TiO2-xHy component. The Fe component thus enables facile activation of N2, while the OV-H in TiO2-xHy hydrogenates the N or NHz to NH3 easily.

Correction to: Particulate matter 2.5 induced arrhythmogenesis mediated by TRPC3 in human induced pluripotent stem cell-derived cardiomyocytes.

During the course of writing and revision of this paper, the authorship changed. Min Ling, M.S. and Qian Bian, Ph.D., are added in the list of authors.

Particulate matter 2.5 induced arrhythmogenesis mediated by TRPC3 in human induced pluripotent stem cell-derived cardiomyocytes.

Particulate matter (PM) is one of the most important environmental issues worldwide, which is associated with not only pulmonary but also cardiovascular diseases. However, the underlying biological mechanisms of PM related cardiovascular dysfunction remained poorly defined, especially mediated by the pathway of direct impact on vascular and heart. Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) provide an ideal platform for studying PM-exposed cellular diseases model in vitro. Here, we investigated the direct effects of particulate matter 2.5 (PM2.5) on hiPSC-CMs and the potential mechanism at non-cytotoxic concentrations. Cell viability, contraction amplitude and spontaneous beating rate of iPSC-CMs after direct exposure to PM2.5 showed that the concentration of lower than 100 µg/ml would not lead to cytotoxic effects. Calcium-mediated optical mapping illustrated that there was a concentration-dependent reduction in quantification of calcium transient amplitude and an increase in the incidence of early after depolarizations due to PM2.5 treatment. Furthermore, there were dramatic dosage-dependent shortening in action potential duration and decrease in L-type calcium peak current density. The Ingenuity Pathway Analysis of our transcriptive study indicated that PM2.5 exposure preferentially influenced the expression of genes involved in calcium signaling. Among them the up-regulation of TRPC3 potentially played an important role in the electrophysiological alteration of PM2.5 on hiPSC-CMs, which could be ameliorated by pretreatment with pyr3, the inhibitor of TRPC3. In conclusion, our results demonstrated that exposure to PM2.5 was capable of increasing propensity to cardiac arrhythmias which could be attenuated with TRPC3 inhibition.

48 × 48 pixelated addressable full-color micro display based on flip-chip micro LEDs.

This paper reports on the design and fabrication of a ${48} \times {48}$48×48 full-color pixelated addressable light-emitting diode on silicon (LEDoS) micro display. The metallization pattern was designed and fabricated on a silicon substrate, while red, green, and blue monochromatic micro LEDs were integrated on the silicon substrate using transfer printing. The red, green, and blue micro LEDs are flip-chip structures in which red micro LEDs were fabricated using substrate transfer, mesa etching, metal deposition, and chip dicing. The integration process does not require wire bonding, which reduces the full-color pixel size and increases the integration speed. The LEDoS micro display can be addressed individually for each LED pixel and display representative patterns.

Feasible development of stable HEK293 clones by CRISPR/Cas9-mediated site-specific integration for biopharmaceuticals production.

OBJECTIVE: To inspect the feasibility of recombinant stable HEK293 cell lines development for biopharmaceuticals production using CRISPR/Cas9-mediated site-specific integration. RESULTS: Using EGFP as a model protein, we first confirmed that the 'safe harbor' AAVS1 locus could be successfully targeted and the exogenous genes could be integrated through homology-directed repair induced by CRISPR/Cas9 technology. Then we constructed a donor plasmid harboring CTLA4Ig gene with an upstream CMV promoter and a downstream puromycin N-acetyltransferase gene to accelerate the efficient integration and selection of CTLA4Ig expression clones. After puromycin enrichment, the transfected pool was diluted for single clone selection, and 12 recombinant clones with CTLA4Ig expression were finally selected with a targeting efficiency of 25.8%. Productivity assay demonstrated that a frequency of 83.3% of selected clone were of consistent productivities, thus illustrating the high efficiency and success rate of this strategy. CONCLUSIONS: CRISPR/Cas9 mediated site-specific integration is an efficient and reliable tool to establishment recombinant stable HEK293 cell lines for both academic and industrial applications.

Rapid Electrical Stimulation Increased Cardiac Apoptosis Through Disturbance of Calcium Homeostasis and Mitochondrial Dysfunction in Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes.

BACKGROUND/AIMS: Heart failure induced by tachycardia, the most common arrhythmia, is frequently observed in clinical practice. This study was designed to investigate the underlying mechanisms. METHODS: Rapid electrical stimulation (RES) at a frequency of 3 Hz was applied on human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) for 7 days, with 8 h/day and 24 h/day set to represent short-term and long-term tachycardia, respectively. Age-matched hiPSC-CMs without electrical stimulation or with slow electrical stimulation (1 Hz) were set as no electrical stimulation (NES) control or low-frequency electrical stimulation (LES) control. Following stimulation, JC-1 staining flow cytometry analysis was performed to examine mitochondrial conditions. Apoptosis in hiPSC-CMs was evaluated using Hoechst staining and Annexin V/propidium iodide (AV/PI) staining flow cytometry analysis. Calcium transients and L-type calcium currents were recorded to evaluate calcium homeostasis. Western blotting and qPCR were performed to evaluate the protein and mRNA expression levels of apoptosis-related genes and calcium homeostasis-regulated genes. RESULTS: Compared to the controls, hiPSC-CMs following RES presented mitochondrial dysfunction and an increased apoptotic percentage. Amplitudes of calcium transients and L-type calcium currents were significantly decreased in hiPSC-CMs with RES. Molecular analysis demonstrated upregulated expression of Caspase3 and increased Bax/Bcl-2 ratio. Genes related to calcium re-sequence were downregulated, while phosphorylated Ca2+/calmodulin-dependent protein kinase II (CaMKII) was significantly upregulated following RES. There was no significant difference between the NES control and LES control groups in these aspects. Inhibition of CaMKII with 1 µM KN93 partly reversed these adverse effects of RES. CONCLUSION: RES on hiPSC-CMs disturbed calcium homeostasis, which led to mitochondrial stress, promoted cell apoptosis and caused electrophysiological remodeling in a time-dependent manner. CaMKII played a central role in the damages induced by RES, pharmacological inhibition of CaMKII activity partly reversed the adverse effects of RES on both structural and electrophysiological properties of cells.

Idiopathic isolated fibrotic atrial cardiomyopathy underlies unexplained scar-related atrial tachycardia in younger patients.

Aims: Unexplained scar-related atrial tachycardia (AT) has been frequently encountered in clinical practice. We hypothesized that idiopathic, isolated fibrotic atrial cardiomyopathy (ACM) underlies this rhythm disorder. This study was aimed to characterize the underlying substrate and to explore the aetiology of this unexplained scar-related AT. Methods and results: Twenty-six (11 men, aged 46 ± 13 years) of 52 non-surgical scar-related AT patients identified by three-dimensional voltage mapping were enrolled in this prospective observational study. Multimodality image examinations (echocardiography, cardiac magnetic resonance, 99Tc single-photon emission computed tomography), ventricular voltage mapping, and intracardiac pressure curve recording ruled out ventricular involvement. Catheter ablation was acutely successful for all the patients, and pacemaker implantation was performed in seven patients who presented sinus node dysfunction or atrial standstill after termination of the AT. In three patients with multiple AT recurrences, the diseased areas of the right atrium were resected and dechannelled via mini-invasive surgical interventions. Histological examinations revealed profound fibrosis without amyloidosis or adipose deposition. Viral and familial investigations yielded negative results. Fibrosis progression over a median of 45 (5-109) months of follow-up manifested as atrial arrhythmia recurrence in seven patients and atrial lead non-capture due to newly developed atrial standstill in two patients. Two patients suffered four ischaemic stroke events before receiving anticoagulation treatment. Conclusion: Isolated, fibrotic ACM may underlie the idiopathic scar-related ATs. This novel cardiomyopathy has unique clinical characteristics with high morbidity including stroke and warrants specific therapeutic strategies. Further investigations are required to determine the aetiology and mechanism.

Dynamic tailoring of electromagnetic behaviors of graphene plasmonic oligomers by local chemical potential.

In the mid-infrared and terahertz (THz) regime, graphene supports tunable surface plasmon resonance (SPR) by controlling the chemical potential, which promotes light-matter interaction at the selected wavelength, showing exceptional promise for optoelectronic applications. In this article, we show that the electromagnetic (EM) response of graphene oligomers can be substantially modified by the modification of the local chemical potential, strengthening or reducing the intrinsic plasmonic modes. The effect mechanism is corroborated by a graphene nanocluster composed of 13 nanodisks with D6h symmetry; by transforming to D3h symmetry, the effect mechanism was retained and more available plasmonic resonance modes appeared. The intriguing properties open a new way to design nanodevices made of graphene oligomers with highly efficient photoresponse enhancement and tunable spectral selectivity for highly accurate photodetection.

Rapid development of stable transgene CHO cell lines by CRISPR/Cas9-mediated site-specific integration into C12orf35.

Chinese hamster ovary (CHO) cells are the most widely used mammalian hosts for recombinant protein production. However, by conventional random integration strategy, development of a high-expressing and stable recombinant CHO cell line has always been a difficult task due to the heterogenic insertion and its caused requirement of multiple rounds of selection. Site-specific integration of transgenes into CHO hot spots is an ideal strategy to overcome these challenges since it can generate isogenic cell lines with consistent productivity and stability. In this study, we investigated three sites with potential high transcriptional activities: C12orf35, HPRT, and GRIK1, to determine the possible transcriptional hot spots in CHO cells, and further construct a reliable site-specific integration strategy to develop recombinant cell lines efficiently. Genes encoding representative proteins mCherry and anti-PD1 monoclonal antibody were targeted into these three loci respectively through CRISPR/Cas9 technology. Stable cell lines were generated successfully after a single round of selection. In comparison with a random integration control, all the targeted integration cell lines showed higher productivity, among which C12orf35 locus was the most advantageous in both productivity and cell line stability. Binding affinity and N-glycan analysis of the antibody revealed that all batches of product were of similar quality independent on integrated sites. Deep sequencing demonstrated that there was low level of off-target mutations caused by CRISPR/Cas9, but none of them contributed to the development process of transgene cell lines. Our results demonstrated the feasibility of C12orf35 as the target site for exogenous gene integration, and strongly suggested that C12orf35 targeted integration mediated by CRISPR/Cas9 is a reliable strategy for the rapid development of recombinant CHO cell lines.

Topologically protected edge states in graphene plasmonic crystals.

A two-dimensional graphene plasmonic crystal composed of periodically arranged graphene nanodisks is proposed. We show that the band topology effect due to inversion symmetry broken in the proposed plasmonic crystals is obtained by tuning the chemical potential of graphene nanodisks. Utilizing this kind of plasmonic crystal, we constructed N-shaped channels and realized topologically edged transmission within the band gap. Furthermore, topologically protected exterior boundary propagation, which is immune to backscattering, was also achieved by modifying the chemical potential of graphene nanodisks. The proposed graphene plasmonic crystals with ultracompact size are subject only to intrinsic material loss, which may find potential applications in the fields of topological plasmonics and high density nanophotonic integrated systems.

Electromagnetic field coupling characteristics in graphene plasmonic oligomers: from isolated to collective modes.

In this paper, we propose a plasmonic tetramer composed of coupled graphene nanodisks. The transformation from the isolated to the collective modes of the proposed structure is investigated by analysing the whispering-gallery modes and extinction spectra with various inter-nanodisk gap distances. In addition, the effect of introducing a central nanodisk into the tetramer on the extinction spectra is explored, which leads to Fano resonance. Furthermore, the refractive index sensing properties of the proposed graphene plasmonic oligomer have been demonstrated. The proposed nanostructures might pave the road toward the application of graphene plasmonic oligomers in fields such as nanophotonics, and chemical or biochemical sensing.