Mucinous neoplasm of the appendix:A case report and review of literature

BACKGROUND Appendiceal mucinous neoplasms(AMNs),although not classified as rare,are relatively uncommon tumors most often discovered incidentally during colorectal surgery.Accurate identification of AMNs is difficult due to non-specific sym-ptoms,overlapping tumor markers with other conditions,and the potential for misdiagnosis.This underscores the urgent need for precision in diagnosis to pre-vent severe complications.CASE SUMMARY This case report describes the unexpected discovery and treatment of a low-grade AMN(LAMN)in a 74-year-old man undergoing laparoscopic hemicolectomy for transverse colon adenocarcinoma(AC).Preoperatively,non-specific gastroin-testinal symptoms and elevated tumor markers masked the presence of AMN.The tumor,presumed to be an AMN peritoneal cyst intraoperatively,was con-firmed as LAMN through histopathological examination.The neoplasm exhibited mucin accumulation and a distinct immunohistochemical profile:Positive for Ho-meobox protein CDX-2,Cytokeratin 20,special AT-rich sequence-binding protein 2,and Mucin 2 but negative for cytokeratin 7 and Paired box gene 8.This profile aids in distinguishing appendiceal and ovarian mucinous tumors.Postoperative recovery was uncomplicated,and the patient initiated adjuvant chemotherapy for the colon AC.CONCLUSION This case highlights the diagnostic complexity of AMNs,emphasizing the need for vigilant identification to avert potential complications,such as pseudomyxoma peritonei.

Colonoscopy plays an important role in detecting colorectal neoplasms in patients with gastric neoplasms

BACKGROUND Gastric cancer(GC)and colorectal cancer(CRC)are the fifth and third most common cancer worldwide,respectively.Nowadays,GC is reported to have a potential predictive value for CRC,especially for advanced CRC.AIM To evaluate the necessity of colonoscopy for gastric neoplasm(GN)patients.METHODS Four databases,including PubMed,EMBASE,the Cochrane Library,and Ovid,were used to perform the search strategy on May 2,2023.The prevalence of colorectal neoplasms(CRN)and baseline characteristics were compared between the neoplasm group and the control group.Continuous variables are expressed as the mean difference and standard deviation.Relationships of categorical variables in the two groups are expressed as odds ratios(OR)and 95%confidence intervals(95%CIs).Subgroup analysis according to different kinds of GNs was conducted for more in-depth analysis.The results of this study are represented by forest plots.Publication bias was evaluated by a funnel plot.All data analyses were performed by STATA SE 16.0 software.RESULTS A total of 3018 patients with GNs and 3905 healthy controls(age and sex matched)were enrolled for analysis.After comparing the prevalence of CRNs between the two groups,CRNs were detected significantly more frequently in GN patients than in controls(OR=1.69,95%CI=1.28 to 2.23,I^(2)=85.12%,P=0.00),especially in patients with GC(OR=1.80,95%CI=1.49 to 2.18,I^(2)=25.55%,P<0.1).Moreover,other risk factors including age(OR=1.08,95%CI=1.00 to 1.17,I^(2)=90.13%,P=0.00)and male sex(OR=2.31,95%CI=1.26 to 4.22,I^(2)=87.35%,P=0.00),were related to the prevalence of CRNs.For patients in the GN group,body mass index(BMI,OR=0.88,95%CI=0.80 to 0.98,I^(2)=0.00%,P=0.92)and smoking(OR=1.03,95%CI=1.01 to 1.05,I^(2)=0.00%,P=0.57)were protective and risk factors for CRNs,respectively.CONCLUSION Patients are recommended to undergo colonoscopy when diagnosed with GNs,especially GC patients with a low BMI and a history of smoking.

Current considerations on intraductal papillary neoplasms of the bile duct and pancreatic duct

Pancreatobiliary intraductal papillary neoplasms(IPNs)represent precursors of pancreatic cancer or bile duct cholangiocarcinoma that can be detected and treated.Despite advances in diagnostic methods,identifying these premalignant lesions is still challenging for treatment providers.Modern imaging,biomarkers and molecular tests for genomic alterations can be used for diagnosis and follow-up.Surgical intervention in combination with new chemotherapeutic agents is considered the optimal treatment for malignant cases.The balance between the risk of malignancy and any risk of resection guides management policy;therefore,treatment should be individualized based on a meticulous preoperative assessment of high-risk stigmata.IPN of the bile duct is more aggressive;thus,early diagnosis and surgery are crucial.The conservative management of low-risk pancreatic branch-duct lesions is safe and effective.

Structural properties of residual carbon in coal gasification fine slag and their influence on flotation separation and resource utilization:A review

Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental benefits.The structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of FS-RC.In this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle size.The reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is summarized.Separation methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the future.The design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the future.The high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization method.This review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the efficient flotation separation of FS,and the expansion of the field of the high value-added utilization of FS-RC.

Tri-modal death distribution towards personalized management of intraductal papillary neoplasm of the bile duct patients:Every story has its own conclusion

The concept of intraductal papillary neoplasm of the bile duct(IPNB)has gained recognition as a discrete entity[1,2],possessing many features including multiplicity[3,4],mucin production[3],slow progression[3,5],various morphology[6,7],easy sloughing and seeding[8],and having unique risk factors[2,9-11].We have previously proposed a morphologic classification[6]and a progression model of IPNB[12].

Residual stress modeling of mitigated fused silica damage sites with CO_(2)laser annealing

A numerical model based on measured fictive temperature distributions is explored to evaluate the residual stress fields of CO_(2)laser-annealed mitigated fused silica damage sites.The proposed model extracts the residual strain from the differences in thermoelastic contraction of fused silica with different fictive temperatures from the initial frozen-in temperatures to ambient temperature.The residual stress fields of mitigated damage sites for the CO_(2)laser-annealed case are obtained by a finite element analysis of equilibrium equations and constitutive equations.The simulated results indicate that the proposed model can accurately evaluate the residual stress fields of laser-annealed mitigated damage sites with a complex thermal history.The calculated maximum hoop stress is in good agreement with the reported experimental result.The estimated optical retardance profiles from the calculated radial and hoop stress fields are consistent with the photoelastic measurements.These results provide sufficient evidence to demonstrate the suitability of the proposed model for describing the residual stresses of mitigated fused silica damage sites after CO_(2)laser annealing.

Residual alkali-evoked cross-linked polymer layer for anti-air-sensitivity LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)cathode

High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs.

Endoscopic ultrasonography-related diagnostic accuracy and clinical significance on small rectal neuroendocrine neoplasms

This research aimed to examine the diagnostic accuracy and clinical significance of endoscopic ultrasonography(EUS)in the context of small rectal neuroendocrine neoplasms(NENs).A total of 108 patients with rectal subepithelial lesions(SELs)with a diameter of<20 mm were included in the analysis.The diagnosis and depth assessment of EUS was compared to the histology findings.The prevalence of NENs in rectal SELs was 78.7%(85/108).The sensitivity of EUS in detecting rectal NENs was 98.9%(84/85),while the specificity was 52.2%(12/23).Overall,the diagnostic accuracy of EUS in identifying rectal NENs was 88.9%(96/108).The overall accuracy rate for EUS in assessing the depth of invasion in rectal NENs was 92.9%(78/84).Therefore,EUS demonstrates reasonable diagnostic accuracy in detecting small rectal NENs,with good sensitivity but inferior specificity.EUS may also assist physicians in assessing the depth of invasion in small rectal NENs before endoscopic excision.

A modified smoothed particle hydrodynamics method considering residual stress for simulating failure and its application in layered rock mass

Residual strength is an indispensable factor in evaluating rock fracture,yet the current Smoothed Particle Hydrodynamics(SPH)framework rarely considers its influence when simulating fracture.An improved cracking strategy considering residual stress in the base bond SPH method was proposed to simulate failures in layered rocks and slopes and verified by experimental results and other simulation methods(i.e.,the discrete element method).Modified Mohr–Coulomb failure criterion was applied to distinguish the mixed failure of tensile and shear.Bond fracture markψwas introduced to improve the kernel function after tensile damage,and the calculation of residual stress after the damage was derived after shear damage.Numerical simulations were carried out to evaluate its performance under different stress and scale conditions and to verify its effectiveness in realistically reproducing crack initiation and propagation and coalescence,even fracture and separation.The results indicate that the improved cracking strategy precisely captures the fracture and failure pattern in layered rocks and rock slopes.The residual stress of brittle tock is correctly captured by the improved SPH method.The improved SPH method that considers residual strength shows an approximately 13%improvement in accuracy for the safety factor of anti-dip layered slopes compared to the method that does not consider residual strength,as validated against analytical solutions.We infer that the improved SPH method is effective and shows promise for applications to continuous and discontinuous rock masses.

Attention-Based Residual Dense Shrinkage Network for ECG Denoising

Electrocardiogram(ECG)signal is one of the noninvasive physiological measurement techniques commonly usedin cardiac diagnosis.However,in real scenarios,the ECGsignal is susceptible to various noise erosion,which affectsthe subsequent pathological analysis.Therefore,the effective removal of the noise from ECG signals has becomea top priority in cardiac diagnostic research.Aiming at the problem of incomplete signal shape retention andlow signal-to-noise ratio(SNR)after denoising,a novel ECG denoising network,named attention-based residualdense shrinkage network(ARDSN),is proposed in this paper.Firstly,the shallow ECG characteristics are extractedby a shallow feature extraction network(SFEN).Then,the residual dense shrinkage attention block(RDSAB)isused for adaptive noise suppression.Finally,feature fusion representation(FFR)is performed on the hierarchicalfeatures extracted by a series of RDSABs to reconstruct the de-noised ECG signal.Experiments on the MIT-BIHarrhythmia database and MIT-BIH noise stress test database indicate that the proposed scheme can effectively resistthe interference of different sources of noise on the ECG signal.

Ghost Module Based Residual Mixture of Self-Attention and Convolution for Online Signature Verification

Online Signature Verification (OSV), as a personal identification technology, is widely used in various industries.However, it faces challenges, such as incomplete feature extraction, low accuracy, and computational heaviness. Toaddress these issues, we propose a novel approach for online signature verification, using a one-dimensionalGhost-ACmix Residual Network (1D-ACGRNet), which is a Ghost-ACmix Residual Network that combines convolutionwith a self-attention mechanism and performs improvement by using Ghost method. The Ghost-ACmix Residualstructure is introduced to leverage both self-attention and convolution mechanisms for capturing global featureinformation and extracting local information, effectively complementing whole and local signature features andmitigating the problem of insufficient feature extraction. Then, the Ghost-based Convolution and Self-Attention(ACG) block is proposed to simplify the common parts between convolution and self-attention using the Ghostmodule and employ feature transformation to obtain intermediate features, thus reducing computational costs.Additionally, feature selection is performed using the random forestmethod, and the data is dimensionally reducedusing Principal Component Analysis (PCA). Finally, tests are implemented on the MCYT-100 datasets and theSVC-2004 Task2 datasets, and the equal error rates (EERs) for small-sample training using five genuine andforged signatures are 3.07% and 4.17%, respectively. The EERs for training with ten genuine and forged signaturesare 0.91% and 2.12% on the respective datasets. The experimental results illustrate that the proposed approacheffectively enhances the accuracy of online signature verification.

Workout Action Recognition in Video Streams Using an Attention Driven Residual DC-GRU Network

Regular exercise is a crucial aspect of daily life, as it enables individuals to stay physically active, lowers thelikelihood of developing illnesses, and enhances life expectancy. The recognition of workout actions in videostreams holds significant importance in computer vision research, as it aims to enhance exercise adherence, enableinstant recognition, advance fitness tracking technologies, and optimize fitness routines. However, existing actiondatasets often lack diversity and specificity for workout actions, hindering the development of accurate recognitionmodels. To address this gap, the Workout Action Video dataset (WAVd) has been introduced as a significantcontribution. WAVd comprises a diverse collection of labeled workout action videos, meticulously curated toencompass various exercises performed by numerous individuals in different settings. This research proposes aninnovative framework based on the Attention driven Residual Deep Convolutional-Gated Recurrent Unit (ResDCGRU)network for workout action recognition in video streams. Unlike image-based action recognition, videoscontain spatio-temporal information, making the task more complex and challenging. While substantial progresshas been made in this area, challenges persist in detecting subtle and complex actions, handling occlusions,and managing the computational demands of deep learning approaches. The proposed ResDC-GRU Attentionmodel demonstrated exceptional classification performance with 95.81% accuracy in classifying workout actionvideos and also outperformed various state-of-the-art models. The method also yielded 81.6%, 97.2%, 95.6%, and93.2% accuracy on established benchmark datasets, namely HMDB51, Youtube Actions, UCF50, and UCF101,respectively, showcasing its superiority and robustness in action recognition. The findings suggest practicalimplications in real-world scenarios where precise video action recognition is paramount, addressing the persistingchallenges in the field. TheWAVd dataset serves as a catalyst for the development ofmore robust and effective fitnesstracking systems and ultimately promotes healthier lifestyles through improved exercise monitoring and analysis.

Radar Signal Intra-Pulse Modulation Recognition Based on Deep Residual Network

In view of low recognition rate of complex radar intra-pulse modulation signal type by traditional methods under low signal-to-noise ratio(SNR),the paper proposes an automatic recog-nition method of complex radar intra-pulse modulation signal type based on deep residual network.The basic principle of the recognition method is to obtain the transformation relationship between the time and frequency of complex radar intra-pulse modulation signal through short-time Fourier transform(STFT),and then design an appropriate deep residual network to extract the features of the time-frequency map and complete a variety of complex intra-pulse modulation signal type recognition.In addition,in order to improve the generalization ability of the proposed method,label smoothing and L2 regularization are introduced.The simulation results show that the proposed method has a recognition accuracy of more than 95%for complex radar intra-pulse modulation sig-nal types under low SNR(2 dB).

CRISPR/Cas9-mediated NlInR2 mutants:Analyses of residual mRNA and truncated proteins

CRISPR/Cas9 technology is a powerful genome manipulation tool in insects.However,little is known about whether mRNA and protein of a target gene are completely cleared in homozygous mutants.This study generated homozygous mutants of the insulin receptor gene 2(NlInR2)in the brown planthopper(Nilaparvata lugens)using CRISPR/Cas9 genome editing.Both frameshift mutants,E5_D17 and E6_I7,differentiated towards long wings,but there were differences in wing morphology,with E5_D17 showing wing deformities.Subsequent investigations revealed the presence of residual expression of NlInR2 mRNA in both mutants,as well as the occurrence of spliceosomes featuring exon skipping splicing in E5_D17.Additionally,the E5_D17 exhibited the detection of N-terminally truncated NlInR2 protein.RNA interference experiments indicated that the knockdown of NlInR2 expression in the E5_D17 mutant line increased the proportion of wing deformities from 11.1 to 65.6%,suggesting that the residual NlInR2 mRNA of the E5_D17 mutant might have retained some genetic functions.Our results imply that systematic characterization of residual protein expression or function in CRISPR/Cas9-generated mutant lines is necessary for phenotypic interpretation.

A method for establishing a bearing residual life prediction model for process enhancement equipment based on rotor imbalance response analysis

A rotating packed bed is a typical chemical process enhancement equipment that can strengthen micromixing and mass transfer.During the operation of the rotating packed bed,the nonreactants and products irregularly adhere to the wire mesh packing in the rotor,thus resulting in an imbalance in the vibration of the rotor,which may cause serious damage to the bearing and material leakage.This study proposes a model prediction for estimating the bearing residual life of a rotating packed bed based on rotor imbalance response analysis.This method is used to determine the influence of the mass on the imbalance in the vibration of the rotor on bearing damage.The major influence on rotor vibration was found to be exerted by the imbalanced mass and its distribution radius,as revealed by the results of orthogonal experiments.Through implementing finite element analysis,the imbalance response curve for the rotating packed bed rotor was obtained,and a correlation among rotor imbalance mass,distribution radius of imbalance mass,and bearing residue life was established via data fitting.The predicted value of the bearing life can be used as the reference basis for an early safety warning of a rotating packed bed to effectively avoid accidents.

Identification of breath volatile organic compounds to distinguish pancreatic adenocarcinoma,pancreatic cystic neoplasm,and patients without pancreatic lesions

BACKGROUND Volatile organic compounds(VOCs)are a promising potential biomarker that may be able to identify the presence of cancers.AIM To identify exhaled breath VOCs that distinguish pancreatic ductal adenocar-cinoma(PDAC)from intraductal papillary mucinous neoplasm(IPMN)and healthy volunteers.METHODS We collected exhaled breath from histologically proven PDAC patients,radiological diagnosis IPMN,and healthy volunteers using the ReCIVA®device between 10/2021-11/2022.VOCs were identified by thermal desorption-gas chromatography/field-asymmetric ion mobility spectrometry and compared between groups.RESULTS A total of 156 participants(44%male,mean age 62.6±10.6)were enrolled(54 PDAC,42 IPMN,and 60 controls).Among the nine VOCs identified,two VOCs that showed differences between groups were dimethyl sulfide[0.73 vs 0.74 vs 0.94 arbitrary units(AU),respectively;P=0.008]and acetone dimers(3.95 vs 4.49 vs 5.19 AU,respectively;P<0.001).After adjusting for the imbalance parameters,PDAC showed higher dimethyl sulfide levels than the control and IPMN groups,with adjusted odds ratio(aOR)of 6.98(95%CI:1.15-42.17)and 4.56(1.03-20.20),respectively(P<0.05 both).Acetone dimer levels were also higher in PDAC compared to controls and IPMN(aOR:5.12(1.80-14.57)and aOR:3.35(1.47-7.63),respectively(P<0.05 both).Acetone dimer,but not dimethyl sulfide,performed better than CA19-9 in PDAC diagnosis(AUROC 0.910 vs 0.796).The AUROC of acetone dimer increased to 0.936 when combined with CA19-9,which was better than CA19-9 alone(P<0.05).CONCLUSION Dimethyl sulfide and acetone dimer are VOCs that potentially distinguish PDAC from IPMN and healthy participants.Additional prospective studies are required to validate these findings.

Direct scaling of residual displacements for bilinear and pinching oscillators

The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the event.An attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model parameters.None of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not available.The statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model alone.The proposed scaling model is applicable to horizontal ground motions in the western U.S.for earthquake magnitudes less than 7 or epicentral distances greater than 20 km.

Trends and hotspots in gastrointestinal neoplasms risk assessment: A bibliometric analysis from 1984 to 2022

BACKGROUND Gastrointestinal neoplasm(GN)significantly impact the global cancer burden and mortality,necessitating early detection and treatment.Understanding the evolution and current state of research in this field is vital.AIM To conducts a comprehensive bibliometric analysis of publications from 1984 to 2022 to elucidate the trends and hotspots in the GN risk assessment research,focusing on key contributors,institutions,and thematic evolution.METHODS This study conducted a bibliometric analysis of data from the Web of Science Core Collection database using the"bibliometrix"R package,VOSviewer,and CiteSpace.The analysis focused on the distribution of publications,contributions by institutions and countries,and trends in keywords.The methods included data synthesis,network analysis,and visualization of international collaboration networks.RESULTS This analysis of 1371 articles on GN risk assessment revealed a notable evolution in terms of research focus and collaboration.It highlights the United States'critical role in advancing this field,with significant contributions from institutions such as Brigham and Women's Hospital and the National Cancer Institute.The last five years,substantial advancements have been made,representing nearly 45%of the examined literature.Publication rates have dramatically increased,from 20 articles in 2002 to 112 in 2022,reflecting intensified research efforts.This study underscores a growing trend toward interdisciplinary and international collaboration,with the Journal of Clinical Oncology standing out as a key publication outlet.This shift toward more comprehensive and collaborative research methods marks a significant step in addressing GN risks.CONCLUSION This study underscores advancements in GN risk assessment through genetic analyses and machine learning and reveals significant geographical disparities in research emphasis.This calls for enhanced global collaboration and integration of artificial intelligence to improve cancer prevention and treatment accuracy,ultimately enhancing worldwide patient care.

Inflammation as a cause of acute myocardial infarction in patients with myeloproliferative neoplasm

Myeloproliferative neoplasms(MPN)are a group of diseases characterized by the clonal proliferation of hematopoietic progenitor or stem cells.They are clinically classifiable into four main diseases:chronic myeloid leukemia,essential thrombocythemia,polycythemia vera,and primary myelofibrosis.These pathologies are closely related to cardio-and cerebrovascular diseases due to the increased risk of arterial thrombosis,the most common underlying cause of acute myocardial infarction.Recent evidence shows that the classical Virchow triad(hypercoagulability,blood stasis,endothelial injury)might offer an explanation for such association.Indeed,patients with MPN might have a higher number and more reactive circulating platelets and leukocytes,a tendency toward blood stasis because of a high number of circulating red blood cells,endothelial injury or overactivation as a consequence of sustained inflammation caused by the neoplastic clonal cell.These abnormal cancer cells,especially when associated with the JAK2V617F mutation,tend to proliferate and secrete several inflammatory cytokines.This sustains a pro-inflammatory state throughout the body.The direct consequence is the induction of a pro-thrombotic state that acts as a determinant in favoring both venous and arterial thrombus formation.Clinically,MPN patients need to be carefully evaluated to be treated not only with cytoreductive treatments but also with cardiovascular protective strategies.

Antagonism effect of residual S triggers the dual-path mechanism for water oxidation

Transition metal chalcogenides(TMCs)are recognized as pre-catalysts,and their(oxy)hydroxides derived from electrochemical reconstruction are the active species in the water oxidation.However,understanding the role of the residual chalcogen in the reconstructed layer is lacking in detail,and the corresponding catalytic mechanism remains controversial.Here,taking Cu_(1-x)Co_(x)S as a platform,we explore the regulating effect and existence form of the residual S doped into the reconstructive layer for oxygen evolution reaction(OER),where a dual-path OER mechanism is proposed.First-principles calculations and operando~(18)O isotopic labeling experiments jointly reveal that the residual S in the reconstructive layer of Cu_(1-x)Co_(x)S can wisely balance the adsorbate evolution mechanism(AEM)and lattice oxygen oxidation mechanism(LOM)by activating lattice oxygen and optimizing the adsorption/desorption behaviors at metal active sites,rather than change the reaction mechanism from AEM to LOM.Following such a dual-path OER mechanism,Cu_(0.4)Co_(0.6)S-derived Cu_(0.4)Co_(0.6)OSH not only overcomes the restriction of linear scaling relationship in AEM,but also avoids the structural collapse caused by lattice oxygen migration in LOM,so as to greatly reduce the OER potential and improved stability.