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Metal-organic frameworks (MOFs) show remarkable potential in a broad array of applications given their physical and chemical versatility. Classical synthesis of MOFs is performed using solution chemistry at elevated temperatures to achieve reversible metal-ligand bond formation. These harsh conditions may not be suitable for chemical species sensitive to high temperature or prone to deleterious reactions with solvents. For instance, Pd(ii) is susceptible to reduction under solvothermal conditions and is not a common metal node of MOFs. We report a generic and facile mechanochemical strategy that directly incorporates a series of Pd(ii)-based heterobimetallic clusters into MOFs as metal nodes without Pd(ii) being reduced to Pd(0). Mechanochemistry features advantages of short reaction time, minimum solvent, high reaction yield, and high degree of synthetic control. Catalytic performances of lattice-confined heterobimetallic sites are examined for nitrene transfer reactions and we demonstrate that the chemoselectivity for allylic amination versus olefin aziridination is readily tuned by the identity of the first-row metal ion in Pd(ii)-based heterobimetallic clusters.
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Infantile hemangiomas are commonly encountered at all levels of medical practice. Clinicians should be aware of their typical clinical history and findings in order to expedite early diagnosis and management. It is also necessary to be aware of differential diagnoses that may mimic infantile hemangiomas but have a more concerning prognosis. The objective of this report is to describe the clinical case of one such mimic, dermatofibrosarcoma protuberans. This report highlights key clinical findings of infantile hemangiomas, while also identifying "red flags" that necessitate urgent additional investigations and referral to a multidisciplinary team. Additionally, key features in the management of both infantile hemangiomas and extremity masses are discussed.
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There is an urgent need for highly efficient sorbents capable of selectively removing 99TcO4- from concentrated alkaline nuclear wastes, which has long been a significant challenge. In this study, we present the design and synthesis of a high-performance adsorbent, CPN-3 (CPN denotes cationic polymeric nanotrap), which achieves excellent 99TcO4- capture under strong alkaline conditions by incorporating branched alkyl chains on the N3 position of imidazolium units and optimizing the framework anion density within the pores of a cationic polymeric nanotrap. CPN-3 features exceptional stability in harsh alkaline and radioactive environments as well as exhibits fast kinetics, high adsorption capacity, and outstanding selectivity with full reusability and great potential for the cost-effective removal of 99TcO4-/ReO4- from contaminated water. Notably, CPN-3 marks a record-high adsorption capacity of 1052 mg/g for ReO4- after treatment with 1 M NaOH aqueous solutions for 24 h and demonstrates a rapid removal rate for 99TcO4- from simulated Hanford and Savannah River Site waste streams. The mechanisms for the superior alkaline stability and 99TcO4- capture performances of CPN-3 are investigated through combined experimental and computational studies. This work suggests an alternative perspective for designing functional materials to address nuclear waste management.
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BACKGROUND: Human tear protein biomarkers are useful for detecting ocular and systemic diseases. Unfortunately, existing tear film sampling methods (Schirmer strip; SS and microcapillary tube; MCT) have significant drawbacks, such as pain, risk of injury, sampling difficulty, and proteomic disparities between methods. Here, we present an alternative tear protein sampling method using soft contact lenses (SCLs). RESULTS: We optimized the SCL protein sampling in vitro and performed in vivo studies in 6 subjects. Using Etafilcon A SCLs and 4M guanidine-HCl for protein removal, we sampled an average of 60 ± 31 µg of protein per eye. We also performed objective and subjective assessments of all sampling methods. Signs of irritation post-sampling were observed with SS but not with MCT and SCLs. Proteomic analysis by mass spectrometry (MS) revealed that all sampling methods resulted in the detection of abundant tear proteins. However, smaller subsets of unique and shared proteins were identified, particularly for SS and MCT. Additionally, there was no significant intrasubject variation between MCT and SCL sampling. CONCLUSIONS: These experiments demonstrate that SCLs are an accessible tear-sampling method with the potential to surpass current methods in sampling basal tears.
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Tripartite ATP-independent periplasmic (TRAP) transporters are secondary-active transporters that receive their substrates via a soluble-binding protein to move bioorganic acids across bacterial or archaeal cell membranes. Recent cryo-electron microscopy (cryo-EM) structures of TRAP transporters provide a broad framework to understand how they work, but the mechanistic details of transport are not yet defined. Here we report the cryo-EM structure of the Haemophilus influenzae N-acetylneuraminate TRAP transporter (HiSiaQM) at 2.99 Å resolution (extending to 2.2 Å at the core), revealing new features. The improved resolution (the previous HiSiaQM structure is 4.7 Å resolution) permits accurate assignment of two Na+ sites and the architecture of the substrate-binding site, consistent with mutagenic and functional data. Moreover, rather than a monomer, the HiSiaQM structure is a homodimer. We observe lipids at the dimer interface, as well as a lipid trapped within the fusion that links the SiaQ and SiaM subunits. We show that the affinity (KD) for the complex between the soluble HiSiaP protein and HiSiaQM is in the micromolar range and that a related SiaP can bind HiSiaQM. This work provides key data that enhances our understanding of the 'elevator-with-an-operator' mechanism of TRAP transporters.
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Haemophilus influenzae , Ácido N-Acetilneuramínico , Haemophilus influenzae/metabolismo , Microscopia Crioeletrônica , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/metabolismoRESUMO
BACKGROUND: Exercise-induced rhinitis (EIR) is a poorly understood phenomenon that may be related to increased inspiratory airflow. Characterization of the development of EIR is important to understand contributing factors. OBJECTIVE: To characterize how different nasal morphologies respond to airflow-related variables during rapid/deep inspiratory conditions. METHODS: Subject-specific nasal airways were reconstructed from radiographic images. Unilateral airways were classified as Standard, Notched, or Elongated accord to their distinct nasal vestibule morphology. Computational fluid dynamics simulations were performed at various airflow rates. RESULTS: For all simulated flow rates, average resistance at the nasal vestibule, airflow velocity and wall sheer stress were highest in Notched. Average mucosal heat flux was highest in Standard. Notched phenotypes showed lower mean percent increases from 10 L/min to 50 L/min in all computed variables. CONCLUSION: Resistance values and airflow velocities depicted a more constricted nasal vestibule in the Notched phenotypes, while perception of nasal mucosal cooling (heat flux) favored the Standard phenotypes. Different nasal phenotypes may predispose to EIR.
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Obstrução Nasal , Rinite , Humanos , Simulação por Computador , Cavidade Nasal/diagnóstico por imagem , Cavidade Nasal/anatomia & histologia , Mucosa Nasal , HidrodinâmicaRESUMO
The recent breakthrough in confining five or more atomic species in nanocatalysts, referred to as high-entropy alloy nanocatalysts (HEAs), has revealed the possibilities of multielemental interactions that can surpass the limitations of binary and ternary electrocatalysts. The wide range of potential surface configurations in HEAs, however, presents a significant challenge in resolving active structural motifs, preventing the establishment of structure-function relationships for rational catalyst design and optimization. We present a methodology for creating sub-5 nm HEAs using an aqueous-based peptide-directed route. Using a combination of pair distribution function and X-ray absorption spectroscopy, HEA structure models are constructed from reverse Monte Carlo modeling of experimental data sets and showcase a clear peptide-induced influence on atomic-structure and chemical miscibility. Coordination analysis of our structure models facilitated the construction of structure-function correlations applied to electrochemical methanol oxidation reactions, revealing the complex interplay between multiple metals that leads to improved catalytic properties. Our results showcase a viable strategy for elucidating structure-function relationships in HEAs, prospectively providing a pathway for future materials design.
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OBJECTIVE: Advances in amyotrophic lateral sclerosis (ALS) gene discovery, ongoing gene therapy trials, and patient demand have driven increased use of ALS genetic testing. Despite this progress, the offer of genetic testing to persons with ALS is not yet "standard of care." Our primary goal is to develop clinical ALS genetic counseling and testing guidelines to improve and standardize genetic counseling and testing practice among neurologists, genetic counselors or any provider caring for persons with ALS. METHODS: Core clinical questions were identified and a rapid review performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA-P) 2015 method. Guideline recommendations were drafted and the strength of evidence for each recommendation was assessed by combining two systems: the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) System and the Evaluation of Genomic Applications in Practice and Prevention (EGAPP). A modified Delphi approach was used to reach consensus among a group of content experts for each guideline statement. RESULTS: A total of 35 guideline statements were developed. In summary, all persons with ALS should be offered single-step genetic testing, consisting of a C9orf72 assay, along with sequencing of SOD1, FUS, and TARDBP, at a minimum. The key education and genetic risk assessments that should be provided before and after testing are delineated. Specific guidance regarding testing methods and reporting for C9orf72 and other genes is provided for commercial laboratories. INTERPRETATION: These evidence-based, consensus guidelines will support all stakeholders in the ALS community in navigating benefits and challenges of genetic testing.
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Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/terapia , Proteína C9orf72/genética , Revisões Sistemáticas como Assunto , Metanálise como Assunto , Testes Genéticos , AconselhamentoRESUMO
Societies in East Asia have utilized domesticated cattle for over 5000 years, but the genetic history of cattle in East Asia remains understudied. Genome-wide analyses of 23 ancient Mongolian cattle reveal that East Asian aurochs and ancient East Asian taurine cattle are closely related, but neither are closely related to any modern East Asian breeds. We observe binary variation in aurochs diet throughout the early Neolithic, and genomic evidence shows millennia of sustained male-dominated introgression. We identify a unique connection between ancient Mongolian aurochs and the European Hereford breed. These results point to the likelihood of human management of aurochs in Northeast Asia prior to and during the initial adoption of taurine cattle pastoralism.
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BACKGROUND: Studies of infants with micrognathia, especially Robin Sequence (RS), are limited by its rarity and both phenotypic and diagnostic variability. Most knowledge of this condition is sourced from small, single-institution samples. METHODS: This is a cross-sectional study including infants with micrognathia admitted to 38 Children's Hospital Neonatal Consortium centers from 2010-2020. Predictor variables included demographic data, birth characteristics, cleft and syndrome status. Outcome variables included length of stay (LOS), death, feeding or respiratory support, and secondary airway operations. RESULTS: 1289 infants with micrognathia had a surgery to correct upper airway obstruction. Mean age and weight at operation were 34.8±1.8 weeks and 3515.4±42 grams, respectively. A syndromic diagnosis was made in 150 (11.6%) patients, with Stickler (5.4%) and Treacher Collins Syndromes (2.2%) most common. Operations included: mandibular distraction osteogenesis (MDO), 66.3%; tracheostomy, 25.4%; and tongue-lip adhesion (TLA), 8.3%. Tracheostomy patients had a lower birth weight, head circumference, gestational age, and APGAR scores. MDO patients were less likely to need a second airway operation compared to TLA patients (3.5%vs17.8%,p<0.001). The proportion of infants feeding exclusively orally at hospital discharge differed significantly, from most to least: MDO, TLA, tracheostomy. Hospital LOS was not statistically different for patients that had MDO and TLA, but was longer for those with primary tracheostomy. Mortality was low for all operations (0.5%). CONCLUSION: In this 1289 surgical patient cohort, MDO was associated with shorter hospital stay, improved oral feeding, and lower rates of secondary airway operations. Prospective multi-center studies are necessary to support these conclusions.
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Background: Dorsal augmentation is one of the more complication-prone procedures in rhinoplasty, demanding ample skill and experience to produce an aesthetic and functional result. Numerous autologous grafts, allografts, xenografts, and alloplastic materials have been attempted for augmentation with varying success. Each graft material has its own unique properties that require varying surgical intricacies. The relative risks and benefits of these strategies and materials are also variable and must be weighed. Alloplastic implants are commonly used in eastern countries, but, due to different patient populations and complication profiles, have found less acceptance among western surgeons. Methods: A PubMed search was done using the terms "dorsal augmentation rhinoplasty," "liquid rhinoplasty," and "grafts used for rhinoplasty." Publication dates ranging from 1957-2022 were included. Abstracts were screened for relevance, and references from each article were reviewed to identify further articles. Chapters on dorsal augmentation from two key rhinoplasty textbooks were also reviewed. Results: A total of 79 articles and 2 textbooks were formally screened; of these, 65 resources were included. Findings were grouped under the headings "facial analysis," "ethnic factors in graft selection," "graft characteristics," "septal cartilage," "auricular cartilage," "costal cartilage," "diced cartilage grafts," "bone grafts," "soft tissue grafts," "nonsurgical/liquid rhinoplasty," and "alloplastic implants." Conclusions: Current dorsal augmentation literature focuses on retrospective studies and expert experiences. There are limited quantitative and prospective studies present to delineate an ideal graft. With consistently advancing technology and knowledge of facial aesthetics, a surgeon must maintain a thorough understanding of the current graft and implant options to offer a specialized treatment plan for each deformity and patient.
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Background: The development of postoperative oronasal fistulae (ONF) is a complication that plagues all cleft surgeons to varying degrees. There is extensive literature discussing the incidence, functional impact, and treatment of ONF. The goal of this article is to provide an extensive review of the literature discussing the incidence, causative factors, functional impact, classification systems, and treatment of ONF. Methods: A literature review was performed using PubMed using the Medical Subject Heading terms "cleft palate" AND "fistula" OR "palatal fistula" OR "oronasal fistula". After review, a total of 356 articles were deemed relevant for this study. Results: Information regarding ONF care, prevention, and management in patients with cleft palate was collected from the articles included in this review. Treatment of ONF remains a challenging problem as there is not a consensus in the available literature on the best palatoplasty techniques for their prevention and treatment. A myriad of reconstructive options and adjunctive therapies exist, and their use is guided by the size and location of the fistula. Conclusions: Fistula treatment should be tailored to the specific needs of the patient, and consideration must be given to not only the ONF itself but also the patient's stage of growth and development. Large-scale, multicenter studies are needed in which ONF are described using standardized nomenclature, and improved outcomes reporting is necessary to better define an algorithm for a truly holistic approach to palate surgery and reduce the incidence of palatal fistula.
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In bacteria and archaea, tripartite ATP-independent periplasmic (TRAP) transporters uptake essential nutrients. TRAP transporters receive their substrates via a secreted soluble substrate-binding protein. How a sodium ion-driven secondary active transporter is strictly coupled to a substrate-binding protein is poorly understood. Here we report the cryo-EM structure of the sialic acid TRAP transporter SiaQM from Photobacterium profundum at 2.97 Å resolution. SiaM comprises a "transport" domain and a "scaffold" domain, with the transport domain consisting of helical hairpins as seen in the sodium ion-coupled elevator transporter VcINDY. The SiaQ protein forms intimate contacts with SiaM to extend the size of the scaffold domain, suggesting that TRAP transporters may operate as monomers, rather than the typically observed oligomers for elevator-type transporters. We identify the Na+ and sialic acid binding sites in SiaM and demonstrate a strict dependence on the substrate-binding protein SiaP for uptake. We report the SiaP crystal structure that, together with docking studies, suggest the molecular basis for how sialic acid is delivered to the SiaQM transporter complex. We thus propose a model for substrate transport by TRAP proteins, which we describe herein as an 'elevator-with-an-operator' mechanism.
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Proteínas de Membrana Transportadoras , Ácido N-Acetilneuramínico , Transporte Biológico , Archaea , Trifosfato de AdenosinaRESUMO
BACKGROUND: Venous thromboembolism (VTE) is a frequent occurrence during treatment for adults with sarcoma. The incidence and underlying risk factors of postsurgical VTE in children and adolescents undergoing resection of sarcoma are unknown. METHODS: Using International Classification of Disease revision-9 diagnostic and procedure codes, the Pediatric Health Information System database was queried for patients aged 18 years and younger, discharged from 2004 to 2015 with a diagnosis of lower extremity malignant neoplasm who had a tumor resection or amputation performed during the encounter. Malignant neoplasms of the pelvic bones and soft tissues were categorized as "pelvis tumors", whereas malignant neoplasms of bone and soft tissues of the lower limbs were categorized as "lower limb tumors". Hospitalizations were evaluated for the occurrence of VTE. Demographic characteristics (age at admission, sex, race, and race/ethnicity) and incidence of VTE were reported. RESULTS: There were 2400 patients identified. Of these, 19 experienced VTE (0.79%) during their surgical hospitalization encounter. By anatomic group, the rate of VTE was 1.4% (CI: 0.5%-3.2%) for tumors in the pelvis and 0.6% (CI: 0.3%-1.0%) in lower limb tumors. Categorizing by age, the incidence of VTE was 1.2% in patients aged zero to 5, 0.3% in patients 6 to 13, and 1.2% in patients 14 to 18 years old. (Table 1). The extremely low rate of VTE occurrence precluded further analysis of risk factors. CONCLUSIONS: In this analysis, postsurgical VTE during hospitalization after pelvic and lower extremity sarcoma resection was an uncommon event in children and adolescents. There seemed to be an increased incidence of postsurgical VTE in pelvic tumors when compared with lower limb tumors, however, the rarity of all events precluded formal statistical analysis. A more robust data set would be required to determine if there are subsets of children and adolescents with sarcoma at higher risk of VTE that could benefit from thromboprophylaxis in the postoperative setting. LEVEL OF EVIDENCE: Level II.
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Sistemas de Informação em Saúde , Sarcoma , Tromboembolia Venosa , Adulto , Adolescente , Humanos , Criança , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Anticoagulantes/uso terapêutico , Incidência , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Hospitalização , Sarcoma/epidemiologia , Sarcoma/cirurgia , Sarcoma/complicações , Fatores de Risco , Extremidade Inferior/cirurgiaRESUMO
Gene duplication events can drive evolution by providing genetic material for new gene functions, and they create opportunities for diverse developmental strategies to emerge between species. To study the contribution of duplicated genes to human early development, we examined the evolution and function of NANOGP1, a tandem duplicate of the transcription factor NANOG. We found that NANOGP1 and NANOG have overlapping but distinct expression profiles, with high NANOGP1 expression restricted to early epiblast cells and naïve-state pluripotent stem cells. Sequence analysis and epitope-tagging revealed that NANOGP1 is protein coding with an intact homeobox domain. The duplication that created NANOGP1 occurred earlier in primate evolution than previously thought and has been retained only in great apes, whereas Old World monkeys have disabled the gene in different ways, including homeodomain point mutations. NANOGP1 is a strong inducer of naïve pluripotency; however, unlike NANOG, it is not required to maintain the undifferentiated status of human naïve pluripotent cells. By retaining expression, sequence and partial functional conservation with its ancestral copy, NANOGP1 exemplifies how gene duplication and subfunctionalisation can contribute to transcription factor activity in human pluripotency and development.
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Genes Homeobox , Células-Tronco Pluripotentes , Animais , Humanos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Células-Tronco Pluripotentes/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
OBJECTIVE: To assess the ability of current 3D printing technology to generate a craniofacial bony and soft tissue anatomical model for use in simulating the performance of a fronto-orbital advancement (FOA) osteotomy and then to further assess the value of the model as an educational tool. DESIGN: Anatomic models were designed with a process of serial anatomic segmentation/design, 3D printing, dissection, and device refinement. A validation study was conducted with 5 junior and 5 senior plastic surgery residents. The validation study incorporated a multiple-choice Knowledge Assessment test (KA), an Objective Structured Assessment of Technical skills (OSATs), a Global Rating Scale (GRS) and a Michigan Standard Simulation Experience Scale (MiSSES). We compared the scores of both the junior and senior residents and compared junior resident scores, before and after viewing a lecture/demonstration. RESULTS: MiSSES showed high face validity with a score of 85.1/90, signifying high satisfaction with the simulator learning experience. Simulation and the lecture/demonstration improved the junior resident average KA score from 5.6/10 to 9.6/10 (Pâ =â .02), OSATs score from 32.4/66 to 64.4/66 (Pâ <â .001) and GRS score from 13.9/35 to 27.5/35 (Pâ <â .001). The senior residents OSATs score of 56.3/66 was higher than the pre-lecture juniors (32.4/66) (Pâ <â .001), but lower than the post-lecture juniors (64.4/66) (Pâ <â .001). CONCLUSION: We have successfully fabricated a 3D printed craniofacial simulator capable of being used as an educational tool alongside traditional surgical training. Next steps would be improving soft tissue realism, inclusion of patient and disease specific anatomy and creation of models for other surgical specialties.
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The behavior of 5f electrons in soft ligand environments makes actinides, and especially transuranium chalcogenides, an intriguing class of materials for fundamental studies. Due to the affinity of actinides for oxygen, however, it is a challenge to synthesize actinide chalcogenides using non-metallic reagents. Using the boron chalcogen mixture method, we achieved the synthesis of the transuranium sulfide NaCuNpS3 starting from the oxide reagent, NpO2. Via the same synthetic route, the isostructural composition of NaCuUS3 was synthesized and the material contrasted with NaCuNpS3. Single crystals of the U-analogue, NaCuUS3, were found to undergo an unexpected reversible hydration process to form NaCuUS3·xH2O (x ≈ 1.5). A large combination of techniques was used to fully characterize the structure, hydration process, and electronic structures, specifically a combination of single crystal, powder, high temperature powder X-ray diffraction, extended X-ray absorption fine structure, infrared, and inductively coupled plasma spectroscopies, thermogravimetric analysis, and density functional theory calculations. The outcome of these analyses enabled us to determine the composition of NaCuUS3·xH2O and obtain a structural model that demonstrated the retention of the local structure within the [CuUS3]- layers throughout the hydration-dehydration process. Band structure, density of states, and Bader charge calculations for NaCuUS3, NaCuUS3·xH2O, and NaCuNpS3 along with X-ray absorption near edge structure, UV-vis-NIR, and work function measurements on ACuUS3 (A = Na, K, and Rb) and NaCuUS3·xH2O samples were carried out to demonstrate that electronic properties arise from the [CuTS3]- layers and show surprisingly little dependence on the interlayer distance.
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An unprecedented sandwich complex of the actinides is synthesized from the treatment of [UI2(HMPA)4]I (HMPA = OP(NMe2)3) (2) with 3 equiv. of K(C14H10) to give the neutral, bis(arenide) species U(η6-C14H10)(η4-C14H10)(HMPA)2 (1). Solid-state X-ray, SQUID magnetometry, and XANES analyses are consistent with tetravalent uranium supported by [C14H10]2- ligands. In one case, treatment of 1 with an equiv. of AgOTf led to the isolation of U(η6-C14H10)2(HMPA)(THF) (3), formed from ring migration and haptotropic rearrangement. Complete active space (CASSCF) calculations indicate the U-C bonding to solely consist of π-interactions, presenting a unique electronic structure distinct from classic actinide sandwich compounds.
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The electrocatalytic CO2 RR to produce value-added chemicals and fuels has been recognized as a promising means to reduce the reliance on fossil resources; it is, however, hindered due to the lack of high-performance electrocatalysts. The effectiveness of sculpturing metal/metal oxides (MMO) heterostructures to enhance electrocatalytic performance toward CO2 RR has been well documented, nonetheless, the precise synergistic mechanism of MMO remains elusive. Herein, an in operando electrochemically synthesized Cr2 O3 -Ag heterostructure electrocatalyst (Cr2 O3 @Ag) is reported for efficient electrocatalytic reduction of CO2 to CO. The obtained Cr2 O3 @Ag can readily achieve a superb FECO of 99.6% at -0.8 V (vs RHE) with a high JCO of 19.0 mA cm-2 . These studies also confirm that the operando synthesized Cr2 O3 @Ag possesses high operational stability. Notably, operando Raman spectroscopy studies reveal that the markedly enhanced performance is attributable to the synergistic Cr2 O3 -Ag heterostructure induced stabilization of CO2 â¢- /*COOH intermediates. DFT calculations unveil that the metallic-Ag-catalyzed CO2 reduction to CO requires a 1.45 eV energy input to proceed, which is 0.93 eV higher than that of the MMO-structured Cr2 O3 @Ag. The exemplified approaches in this work would be adoptable for design and development of high-performance electrocatalysts for other important reactions.
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Bismuth-based materials (e.g., metallic, oxides and subcarbonate) are emerged as promising electrocatalysts for converting CO2 to formate. However, Bio-based electrocatalysts possess high overpotentials, while bismuth oxides and subcarbonate encounter stability issues. This work is designated to exemplify that the operando synthesis can be an effective means to enhance the stability of electrocatalysts under operando CO2RR conditions. A synthetic approach is developed to electrochemically convert BiOCl into Cl-containing subcarbonate (Bi2O2(CO3)xCly) under operando CO2RR conditions. The systematic operando spectroscopic studies depict that BiOCl is converted to Bi2O2(CO3)xCly via a cathodic potential-promoted anion-exchange process. The operando synthesized Bi2O2(CO3)xCly can tolerate - 1.0 V versus RHE, while for the wet-chemistry synthesized pure Bi2O2CO3, the formation of metallic Bio occurs at - 0.6 V versus RHE. At - 0.8 V versus RHE, Bi2O2(CO3)xCly can readily attain a FEHCOO- of 97.9%, much higher than that of the pure Bi2O2CO3 (81.3%). DFT calculations indicate that differing from the pure Bi2O2CO3-catalyzed CO2RR, where formate is formed via a *OCHO intermediate step that requires a high energy input energy of 2.69 eV to proceed, the formation of HCOO- over Bi2O2(CO3)xCly has proceeded via a *COOH intermediate step that only requires low energy input of 2.56 eV.