The prevalence of nasopharyngeal carcinoma(NPC) is higher in southern China, Hong Kong, and Taiwan than in other areas in the world. Radiotherapy is an important part of treatment for NPC patients, especially those wi...The prevalence of nasopharyngeal carcinoma(NPC) is higher in southern China, Hong Kong, and Taiwan than in other areas in the world. Radiotherapy is an important part of treatment for NPC patients, especially those with stage Ⅲ/Ⅳ disease. Subdural empyema is a rare but life-threatening complication in postradiotherapy NPC patients which should be paid more attention. Here, we present the case of a 64-year-old female postradiotherapy NPC patient with subdural empyema complicated with intracranial hemorrhage. She was treated by burr-hole surgery but unfortunately died because of recurrent intracranial hemorrhage. The mechanisms potentially underlying the formation of subdural empyema in postradiotherapy NPC patients and the surgical strategies that can be used in these patients are discussed in this report.展开更多
Development of efficient and stable metal catalysts for the selective aqueous phase hydrodeoxygenation(HDO)of biomass-derived oxygenates to value-added biofuels is highly desired.An innovative surface microenvironment...Development of efficient and stable metal catalysts for the selective aqueous phase hydrodeoxygenation(HDO)of biomass-derived oxygenates to value-added biofuels is highly desired.An innovative surface microenvironment modulation strategy was used to construct the nitrogen-doped hollow carbon sphere encapsulated with Pd(Pd@NHCS-X,X:600–800)nanoreactors for catalytic HDO of biomass-derived vanillin in water.The specific surface microenvironments of Pd@NHCS catalysts including the electronic property of active Pd centers and the surface wettability and porous structure of NHCS supports could be well-controlled by the calcination temperature of catalysts.Intrinsic kinetic evaluations demonstrated that the Pd@NHCS-600 catalyst presented a high turnover frequency of 337.77 h^(–1)and a low apparent activation energy of 18.63 kJ/mol.The excellent catalytic HDO performance was attributed to the unique surface microenvironment of Pd@NHCS catalyst based on structure-performance relationship analysis and DFT calculations.It revealed that pyridinic N species dominated the electronic property regulation of Pd sites through electronic metal-support interaction(EMSI)and produced numerous electron-rich active Pd centers,which not only intensified the dissociation and activation of H2 molecules,but also substantially improved the activation capability of vanillin via the enhanced adsorption of–C=O group.The fine hydrophilicity and abundant porous structure promoted the uniform dispersion of catalyst and ensured the effective access of reactants to catalytic active centers in water.Additionally,the Pd@NHCS-600 catalyst exhibited excellent catalytic stability and broad substrate applicability for the selective aqueous phase HDO of various biomass-derived carbonyl compounds.The proposed surface microenvironment modulation strategy will provide a new consideration for the rational design of high-performance nitrogen-doped carbon-supported metal catalysts for catalytic biomass transformation.展开更多
Accurate quantification of life-cycle greenhouse gas(GHG)footprints(GHG_(fp))for a crop cultivation system is urgently needed to address the conflict between food security and global warming mitigation.In this study,t...Accurate quantification of life-cycle greenhouse gas(GHG)footprints(GHG_(fp))for a crop cultivation system is urgently needed to address the conflict between food security and global warming mitigation.In this study,the hydrobiogeochemical model,CNMM-DNDC,was validated with in situ observations from maize-based cultivation systems at the sites of Yongji(YJ,China),Yanting(YT,China),and Madeya(MA,Kenya),subject to temperate,subtropical,and tropical climates,respectively,and updated to enable life-cycle GHG_(fp)estimation.The model validation provided satisfactory simulations on multiple soil variables,crop growth,and emissions of GHGs and reactive nitrogen gases.The locally conventional management practices resulted in GHG_(fp)values of 0.35(0.09–0.53 at the 95%confidence interval),0.21(0.01–0.73),0.46(0.27–0.60),and 0.54(0.21–0.77)kg CO_(2)e kg~(-1)d.m.(d.m.for dry matter in short)for maize–wheat rotation at YJ and YT,and for maize–maize and maize–Tephrosia rotations at MA,respectively.YT's smallest GHG_(fp)was attributed to its lower off-farm GHG emissions than YJ,though the soil organic carbon(SOC)storage and maize yield were slightly lower than those of YJ.MA's highest SOC loss and low yield in shifting cultivation for maize–Tephrosia rotation contributed to its highest GHG_(fp).Management practices of maize cultivation at these sites could be optimized by combination of synthetic and organic fertilizer(s)while incorporating 50%–100%crop residues.Further evaluation of the updated CNMM-DNDC is needed for different crops at site and regional scales to confirm its worldwide applicability in quantifying GHG_(fp)and optimizing management practices for achieving multiple sustainability goals.展开更多
BACKGROUND In recent years,the number of studies on spondylolisthesis has been increasing,and there are many publications on this disorder.To our knowledge,there is no bibliometric analysis of spondylolisthesis to dat...BACKGROUND In recent years,the number of studies on spondylolisthesis has been increasing,and there are many publications on this disorder.To our knowledge,there is no bibliometric analysis of spondylolisthesis to date.AIM To investigate emerging directions in Spondylolisthesis research and systematically evaluate the academic literature with the highest citation impact within this field.METHODS All data were collected from the Web of Science Core Collection database.Years of publications,countries,journals,institutions and total number of citations were extracted and analyzed by VOSviewer software.In addition,we analyzed the top 100 most-cited articles on spondylolisthesis.RESULTS A total of 1831 articles related to spondylolisthesis were identified.The frequency of publications on spondylolisthesis has increased dramatically over time.Among all countries,United States has contributed the most publications on spondylolisthesis(n=574).The institution with the most articles was the University of California,San Francisco(n=52).Spine topped the list of journals and has published 291 spondylolisthesis-related reports.The hotspot of research changed from posterolateral fusion to interbody fusion.CONCLUSION In recent years,academic investigations on spondylolisthesis have exhibited significant growth.As the inaugural bibliometric evaluation in this domain,our research establishes a methodological framework for synthesizing the historical progression and current advancements of spondylolisthesis studies.展开更多
Long-term niche differentiation will lead to the evolution of diverse adaptive strategies for species in diverse environments. The present study selected two Forsythia species, Forsythia mandshurica(Fm)-which naturall...Long-term niche differentiation will lead to the evolution of diverse adaptive strategies for species in diverse environments. The present study selected two Forsythia species, Forsythia mandshurica(Fm)-which naturally occurs in a cold temperate zone and Forsythia suspensa(Fs)-which thrives in a warm temperate zone-to reveal their differential chilling defense mechanisms by integrating morpho-physiological,transcriptomic, and metabolomic data. Transcriptome results show that Fm has evolved in a series of adaptive mechanisms designed to help the plants to cope with chilling stress by enhancing sugar, amino acid, hormone, polyamine, and phenol content to improve cell osmotic potential and to mitigate petal browning. Metabolomic data suggested the increased chilling resistance of Fm relies on in the plant being rich in a-linolenic acid, linoleic acid, as well as two amino acids, Phe and Trp, and has low levels of cinnamic acid and gramine in flowers compared to Fs. A higher abundance of glutathione disulfide and NADPH regulated by glutathione peroxidases and NADPH improved the ability of the cellular antioxidant and reduction-oxidation system stability in Fm;Additionally, the elevated levels of pyruvate, a-ketoglutaric acid, and oxaloacetic acid in Fm contributed to a significantly enhanced ATP production in mitochondria. Through Ka/Ks and gene expression analysis,four transcription factors, EVM0025036(bHLH), EVM0010639 and EVM0007275(AP2), and EVM0025908(bZIP) were identified that may contribute to the high cold tolerance of Fm. These adaptations highlight the intricate interplay between genetic and physiological processes that shape the survival strategies of plants in response to their specific ecological niches.展开更多
Fiber Metal Laminates(FMLs),as high-performance composite materials,demonstrate exceptional potential in a wide range of applications,such as aeronautical and astronautical industries.However,the traditional cured FML...Fiber Metal Laminates(FMLs),as high-performance composite materials,demonstrate exceptional potential in a wide range of applications,such as aeronautical and astronautical industries.However,the traditional cured FMLs possess complex interlayer stresses and low forming limits,restricting further promotion and application of FMLs.Low-constraint FMLs exhibit a lower forming resistance and better formability due to no curing during the forming process;however,the formation mechanism and response are not clear.This paper presents the Forming Limit Diagram(FLD)of low-constraint GLARE(glass fiber reinforced aluminum laminates)based on the forming limit test,and compares it with the conventionally cured laminates to evaluate the differences in the forming limit.In addition,combined with the analysis of failure mechanism and micro-deformation mechanism of specimens,the influence of different temperatures(20–80℃)and forming states(width)on the deformation performance of laminates is further explored.The results reveal that the forming limit curve of low-constraint laminates shifts up with the increase of temperature,the forming limit initially increases with the increase of width,then followed by a gradual decrease,and the maximum principal strain of low-constraint laminates is increased by 29% at 80℃ compared to 20℃.The cured laminate has a principal strain range of 0–0.02,while the low-constraint laminates have a principal strain range of 0.03–0.14.Compared with cured laminates,low-constraint laminates possess a higher forming limit due to the improvement in deformable degree between layers by resin flow and fiber slippage,which enhances their formability.This study is expected to serve as a reference for establishing forming limit criteria and optimizing forming schemes for low-constraint laminates.展开更多
The performance of welded Ni-based superalloys at high temperatures is essential to be evaluated due to their particular service environment for aero-engines and high-speed aircrafts.The tensile properties and related...The performance of welded Ni-based superalloys at high temperatures is essential to be evaluated due to their particular service environment for aero-engines and high-speed aircrafts.The tensile properties and related microstructural evolutions such as the carbide precipitate and grain of a laser-welded Ni-based alloy were experimentally and numerically investigated at different temperatures(20,300,500,800℃).The results show that at room temperature,the strength of the Base Material(BM)was slightly smaller,with a difference of less than 1%,than the Welded Material(WM),which can be attributed to the more uniformly distributed needle-shaped carbide precipitates in the WM than those nonuniformly coarser spherical ones in the BM.While at 300℃ and 500℃,the strength of WM decreased more obviously compared with that of BM due to the more apparent growth of grain:13.52%loss in yield strength in WM alloys as compared with BM alloys at 300℃,and 16.57% at 500℃.At 800℃,the strength of BM and WM both decreased to a similar level due to Dynamic Recrystallization(DRX).However,a much higher elongation was observed for the BM than WM(less than 50%of BM),which can be attributed to the enhanced dislocation accumulation capability of the large spherical carbides along grain boundaries on the fracture surface in BM.Furthermore,a unified model considering the welding effects on both microstructures(dislocation,carbides,and grain)and mechanical properties evolutions at different temperatures was developed and validated.Based on this model,the key temperature ranges(20–600℃)where apparent weakening of strength and uniform plasticity occurs for welded structures were identified,providing a direct guidance for potential structure and process design.展开更多
Objective:This study aimed to develop and validate a predictive model for postoperative complications in gastrointestinal cancer patients using a large multicenter database,based on machine learning algorithms.Methods...Objective:This study aimed to develop and validate a predictive model for postoperative complications in gastrointestinal cancer patients using a large multicenter database,based on machine learning algorithms.Methods:We analyzed the clinicopathological data of 3,926 gastrointestinal cancer patients from the Prevalence of Abdominal Complications After GastroEnterological surgery(PACAGE)database,covering 20 medical centers from December 2018 to December 2020.The predictive performance was evaluated using receiver operating characteristic(ROC)curves and Brier Score.Results:The patients were divided into gastric(2,271 cases)and colorectal cancer(1,655 cases)groups and further divided into training and external validation sets.The overall postoperative complication rates for gastric and colorectal cancer groups were 18.1%and 14.8%,respectively.The most common complication was the intraabdominal infection in both gastric and colorectal cancer groups.In the training set,the Random Forest(RF)model predicted the highest mean area under the curve(AUC)values for overall complications and different types of complications,in both the gastric cancer group and the colorectal cancer group,with similar results obtained in the external validation set.ROC curve analysis showed good predictive performance of the RF model for overall and infectious complications.An application-based clinical tool was developed for easy application in clinical practice.Conclusions:This model demonstrated good predictive performance for overall and infectious complications based on the multi-center database,supporting clinical decision-making and personalized treatment strategies.展开更多
Silicon,a leading candidate for electrode material for lithium-ion batteries,has garnered significant attention.During the initial lithiation process,the alloying reaction between silicon and lithium transforms the pr...Silicon,a leading candidate for electrode material for lithium-ion batteries,has garnered significant attention.During the initial lithiation process,the alloying reaction between silicon and lithium transforms the pristine silicon microstructure from crystalline to amorphous,resulting in plastic deformation of the amorphous phase.This study proposes the free volume theory to develop a fully coupled Cahn-Hilliard phase-field model that integrates viscoplastic deformation,free volume evolution,and diffusion.This model investigates the chemophysical phenomenon of self-limiting behavior occurring during the initial lithiation of silicon anodes.Unlike most existing models,the proposed model considers free volume-dependent diffusion using a physically-based approach.The model’s temporal variation in the lithiated phase thickness aligns well with experimental results,confirming the model’s accuracy.Stress field calculations reveal the coexistence of compressive and tensile stresses within the lithiated phase,which may not cause the limiting effect under the frame of the stress-induced diffusion.Analyses indicate that high effective stress increases free volume,enhancing lithium diffusion and augmenting the diffusion coefficient.Reducing the diffusion coefficient in the lithiated phase due to free volume evolution is the primary cause of self-limiting lithiation.展开更多
Population size plays a crucial role in determining wheat yields.Altered carbohydrate accumulation resulting from increased competition between populations and individuals leads to poor-quality stems.The sowing date c...Population size plays a crucial role in determining wheat yields.Altered carbohydrate accumulation resulting from increased competition between populations and individuals leads to poor-quality stems.The sowing date can mitigate competition in densely planted populations.However,the underlying mechanism by which it confers resistance to wheat lodging remains elusive.In this study,Zimai 28(lodging-sensitive variety) and Shannong 28(lodging-resistant variety) were used with three sowing treatments on October 22(S1),October 28(S2),and November 3(S3).The sowing rate was adjusted to ensure adequate population size and consistency in the overwintering populations across sowing dates(300 plant m^(-2)for S1,375 plant m^(-2)for S2,and 525 plant m^(-2)for S3),The lodging resistance in winter wheat was increased by delayed sowing and increased sowing rate,which led to a reduction in tiller numbers and fostered primary stem development.A reduction in the overwinter cumulative temperature from 500 to 450℃,coupled with an elevation in sowing rates from 300 to 375 plant m^(-2)(transition from S1 to S2),corresponded with a notable increase in structural carbohydrates(lignin,cellulose,hemicellulose,and pectin) by 175.07 mg g^(-1).Additionally,there was a moderate increase in non-structural carbohydrates,including soluble sugars and starch,by 15.54 mg g^(-1).Delayed sowing and increased sowing rate elevated the precursor contents of lignin synthesis.Enhanced metabolic activity of related pathways ultimately increased dimer/trimer content.In summary,this study highlights the pivotal role of lignin metabolites and cross-linked structures in determining the stem stiffness breaking strength.展开更多
Electrochemically induced surface reconstruction offers a novel approach for in situ modulation of the surface structure of nanomaterials.However,comprehensive studies on the surface reconstruction behavior of nanomat...Electrochemically induced surface reconstruction offers a novel approach for in situ modulation of the surface structure of nanomaterials.However,comprehensive studies on the surface reconstruction behavior of nanomaterials under diverse electrochemical operations remain limited.Here,exemplified by three electrochemical operations,including cyclic voltammetry(CV),squarewave potential(SWP)and chronoamperometry(CA),we reveal the structural evolution behavior and the corresponding electrocatalytic activity of bimetallic telluride hollow nanorods(Ir_(1-x)Ru_(x)0Te_(2)HNRs).It was found that the surface Te atoms in Ir_(1-x)Ru_(x)0Te_(2)HNRs undergo preferential leaching during the CV and SWP processes,ultimately leading to the formation of a metal alloy shell.In contrast,during the CA process,the surface reconstruction induced by Te leaching was suppressed by the adsorption of anions on the electrode surface.Electrocatalytic tests show that the CV activated Ir_(0.75)Ru_(0.25)Te_(2)HNRs exhibit excellent activity for the hydrogen oxidation reaction in 0.1 M KOH,with a mass activity of 686 Ag^(-1)at an overpotential of50 mV,which is 2.9 times higher than that of commercialPt/C catalyst.Density functional theory(DFT)computation reveals that the incorporation of Ru optimizes the hydroxyl binding energy of IrRu alloy,thus resulting in the reduced reaction energy barrier of hydrogen oxidation reaction.This work provides a new insight into the design of efficient catalysts through electrochemical surface engineering.展开更多
Oxygen release from Ni-rich cathode is one of the major structural degradations resulting in rapid performance fading in lithium-ion batteries(LIBs).The energy gap between the transition metals(TM)-d band and the O-p ...Oxygen release from Ni-rich cathode is one of the major structural degradations resulting in rapid performance fading in lithium-ion batteries(LIBs).The energy gap between the transition metals(TM)-d band and the O-p band serves as an effective evaluation metric in characterizing the potential for oxygen release.Given that the primary oxidation factors of NCM811 materials vary at different states of charge(SOC),this study employs high-throughput density functional theory(DFT)calculations combined with machine learning(ML)to systematically investigate the regulation mechanism of heteroatoms on the energy gap between the TM-d band(TM=Ni,Co)and O-p band at various SOC levels.Highthroughput DFT calculations were used to study doping thermodynamic stability and complete the database.The results indicate that dopant atoms remain at their original sites even at 50%SOC.Correlation analysis reveals that at 0 SOC,the dopant reduces Ni-O bonding interactions by forming its own bonds with oxygen,thereby preventing lattice oxygen escape and weakening the oxygen binding of the system during Ni redox.At 50%SOC,the dopant and Co atoms synergistically strengthen their bonding interactions with oxygen,thereby maintaining structural stability and inhibiting lattice oxygen escape.Based on R^(2)and root-mean-square error(RMSE),the gradient boosting regression(GBR)algorithm is identified as optimal for predicting the energy gaps between the Ni-d band and O-p band,as well as between the Co-d band and O-p band.Feature importance analysis demonstrates that the magnetic moment(Dma)of the doped atom significantly contributes to the prediction of ΔNi-O and ΔCo-O.In this study,the energy gap regulation mechanisms of Ni-d/O-p and Co-d/O-p are systematically investigated using non-empirical first principle calculations combined with data-driven machine learning,aiming to provide insights into the electrochemical stability of NCM811 and related materials.展开更多
BACKGROUND The hepatic venous pressure gradient serves as a crucial parameter for assessing portal hypertension and predicting clinical decompensation in individuals with cirrhosis.However,owing to its invasive nature...BACKGROUND The hepatic venous pressure gradient serves as a crucial parameter for assessing portal hypertension and predicting clinical decompensation in individuals with cirrhosis.However,owing to its invasive nature,there has been growing interest in identifying noninvasive alternatives.Transient elastography offers a promising approach for measuring liver stiffness and spleen stiffness,which can help estimate the likelihood of decompensation in patients with chronic liver disease.AIM To investigate the predictive ability of the liver stiffness measurement(LSM)and spleen stiffness measurement(SSM)in conjunction with other noninvasive indicators for clinical decompensation in patients suffering from compensatory cirrhosis and portal hypertension.METHODS This study was a retrospective analysis of the clinical data of 200 patients who were diagnosed with viral cirrhosis and who received computed tomography,transient elastography,ultrasound,and endoscopic examinations at The Second Affiliated Hospital of Xi’an Jiaotong University between March 2020 and November 2022.Patient classification was performed in accordance with the Baveno VI consensus.The area under the curve was used to evaluate and compare the predictive accuracy across different patient groups.The diagnostic effectiveness of several models,including the liver stiffness-spleen diameter-platelet ratio,variceal risk index,aspartate aminotransferase-alanine aminotransferase ratio,Baveno Ⅵ criteria,and newly developed models,was assessed.Additionally,decision curve analysis was carried out across a range of threshold probabilities to evaluate the clinical utility of these predictive factors.RESULTS Univariate and multivariate analyses demonstrated that SSM,LSM,and the spleen length diameter(SLD)were linked to clinical decompensation in individuals with viral cirrhosis.On the basis of these findings,a predictive model was developed via logistic regression:Ln[P/(1-P)]=-4.969-0.279×SSM+0.348×LSM+0.272×SLD.The model exhibited strong performance,with an area under the curve of 0.944.At a cutoff value of 0.56,the sensitivity,specificity,positive predictive value,and negative predictive value for predicting clinical decompensation were 85.29%,88.89%,87.89%,and 86.47%,respectively.The newly developed model demonstrated enhanced accuracy in forecasting clinical decompensation among patients suffering from viral cirrhosis when compared to four previously established models.CONCLUSION Noninvasive models utilizing SSM,LSM,and SLD are effective in predicting clinical decompensation among patients with viral cirrhosis,thereby reducing the need for unnecessary hepatic venous pressure gradient testing.展开更多
Recycling-oriented alloy design is a crucial part of material sustainability,as it reduces the need for raw material extraction and minimises environmental impact.This requires that scraps be reused or repurposed effe...Recycling-oriented alloy design is a crucial part of material sustainability,as it reduces the need for raw material extraction and minimises environmental impact.This requires that scraps be reused or repurposed effectively,even when the scraps are co-mingled and have higher costs for further sorting and separation.In this work,we explore an alloy design concept by creating a compositionally flexible domain that can recycle multiple alloy grades and yet maintain relatively consistent properties across chemical variations.This is demonstrated through the Fe-Cr-Ni-Mn system to identify compositionally flexible austenitic stainless steels(CF-ASS)and accommodate the recycling of mixed austenitic stainless steel scraps.Alloys within the nominal composition spaces exhibit relatively consistent mechanical properties and corrosion resistance despite significant variations in different alloy compositions.We illustrate how we can utilise the compositionally flexible austenitic stainless steels to recycle mixed 200 and 300-series stainless steel and ferronickel scraps,demonstrating its practical viability.While this demonstration focuses on the stainless steel system,the underlying principles can be extended to other systems related to mixed scrap recycling.展开更多
This paper establishes an amplitude modulation heating model, simulating the far-field radiation of ELF/VLF signals generated by modulation heating, as well as the specific location and longitudinal extent of the radi...This paper establishes an amplitude modulation heating model, simulating the far-field radiation of ELF/VLF signals generated by modulation heating, as well as the specific location and longitudinal extent of the radiation source. We consider various modulation waveforms and find that square-wave modulation has the highest excitation efficiency for ELF/VLF signals, and that square-wave modulation with a smaller duty cycle(<50%) exhibits higher excitation efficiency for ELF/VLF signals, while the sin^(2)t waveform modulation yields the lowest proportion of harmonic energy in the generated signals. The amplitude of the second harmonic generated by the sin^(2)t waveform is less than one-tenth that of the fundamental frequency, and the energy of higher-frequency harmonics can be negligibly small compared with those of the fundamental wave. It is a challenging task to achieve a balance between enhancing the excitation efficiency of ELF/VLF signals and also suppressing harmonics generated by the modulated heating process. This is because the harmonics are correspondingly enhanced as the excitation efficiency of the signals is increased. However, we find that under conditions of varying effective radiant power and modulation frequency, as long as the modulation waveform is unchanged, the energy ratio between the fundamental frequency signal generated by modulated heating and each harmonic is relatively fixed, with changes only in signal intensity and the location of the radiation source zone. This implies that one can first select modulation waveforms that make the signal less prone to distortion, then increase the effective radiated power to enhance the signal strength, without concern for harmonic interference of the fundamental signal.展开更多
AIM: To retrospectively analyze the computed tomography (CT) and magnetic resonance imaging (MRI) appearances of primary clear cell carcinoma of the liver (PCCCL) and compare the imaging appearances of PCCCL and commo...AIM: To retrospectively analyze the computed tomography (CT) and magnetic resonance imaging (MRI) appearances of primary clear cell carcinoma of the liver (PCCCL) and compare the imaging appearances of PCCCL and common type hepatocellular carcinoma (CHCC) to determine whether any differences exist between the two groups. METHODS: Twenty cases with pathologically proven PCCCL and 127 cases with CHCC in the Second Affiliated Hospital of Sun Yat-sen University were included in this study. CT or MRI images from these patients were retrospectively analyzed. The following imaging findings were reviewed: the presence of liver cirrhosis, tumor size, the enhancement pattern on dynamic contrast scanning, the presence of pseudo capsules, tumor rupture, portal vein thrombosis and lymph node metastasis. RESULTS: Both PCCCL and CHCC were prone to occur in patients with liver cirrhosis, the association rate of liver cirrhosis was 80.0% and 78.7%, respectively (P > 0.05). The mean sizes of PCCCL and CHCC tumors were (7.28 ± 4.25) cm and (6.96 ± 3.98) cm, respectively. Small HCCs were found in 25.0% (5/20) of PCCCL and 19.7% (25/127) of CHCC cases. No significant differences in mean size and ratio of small HCCs were found between the two groups (P = 0.658 and 0.803, respectively). Compared with CHCC patients, PCCCL patients were more prone to form pseudo capsules (49.6% vs 75.0%, P = 0.034). Tumor rupture, typical HCC enhancement patterns and portal vein tumor thrombosis were detected in 15.0% (3/20), 72.2% (13/18) and 20.0% (4/20) of patients with PCCCL and 3.1% (4/127), 83.6% (97/116) and 17.3% (22/127) of patients with CHCC, respectively. There were no significant differences between the two groups (all P > 0.05). No patients with PCCCL and 2.4% (3/127) of patients with CHCC showed signs of lymph node metastasis (P > 0.05). CONCLUSION: The imaging characteristics of PCCCL are similar to those of CHCC and could be useful for differentiating these from other liver tumors (such as hemangioma and hepatic metastases). PCCCLs are more prone than CHCCs to form pseudo capsules.展开更多
Background: Gastroenteropancreatic neuroendocrine neoplasms(GEP-NENs) are a heterogeneous group of rare tumors. Many issues in terms of epidemiologic features, pathogenesis, and treatment of GEP-NENs are still under d...Background: Gastroenteropancreatic neuroendocrine neoplasms(GEP-NENs) are a heterogeneous group of rare tumors. Many issues in terms of epidemiologic features, pathogenesis, and treatment of GEP-NENs are still under discussion. Our study aimed to analyze the clinicopathologic characteristics and prognosis of Chinese patients with GEP-NENs.Methods: Complete clinicopathologic data and survival information of 1183 patients with GEP-NENs treated between 2005 and 2015 were collected from five medical centers in Guangdong Province, China. Patient survival was estimated using the Kaplan–Meier method and analyzed using the log-rank test; prognostic factors were analyzed using the Cox proportional hazards model.Results: The most common tumor location was the rectum(37.4%), followed by the pancreas(28.1%), stomach(20.7%), small intestine(7.2%), appendix(3.4%), and colon(3.3%). After initial definitive diagnosis, 1016(85.9%) patients underwent surgery. The 1-, 3-, and 5-year overall survival(OS) rates for the entire cohort were 87.9%, 78.5%, and 72.8%, respectively. The 3-year OS rates of patients with G1, G2, and G3 tumors were 93.1%, 82.7%, and 43.1%, respectively(P < 0.001). The 3-year OS rates of patients with stage I, II, III, and IV tumors were 96.0%, 87.3%, 64.0%, and 46.8%, respectively(P < 0.001). Patients with distant metastasis who underwent palliative surgery had a longer survival than those who did not(P = 0.003). Similar survival benefits of palliative surgery were observed in patients with neuroendocrine tumor(P y, M category, and sur= 0.031) or neuroendocrine carcinoma(P gery were found to be independent prog= 0.046). In multivariate analysis, age, grade, N categornostic factors.Conclusions: Patients with GEP-NENs who are women, younger than 50 years old, have smaller tumor size, have lower tumor grade, have lower T/N/M category, and who undergo surgery can have potentially longer survival time. Our data showed that surgery can improve the prognosis of GEP-NEN patients with distant metastasis. However, randomized controlled trials need to be conducted to establish the optimal criteria for selecting patients to undergo surgery.展开更多
Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the...Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the coordination with virtual power plants(VPPs).The proposed strategy improves systemflexibility and responsiveness by optimizing the power adjustment of flexible resources.In the proposed strategy,theGaussian Process Regression(GPR)is firstly employed to determine the adjustable range of aggregated power within the VPP,facilitating an assessment of its potential contribution to power supply support.Then,an optimal dispatch model based on a leader-follower game is developed to maximize the benefits of the VPP and flexible resources while guaranteeing the power balance at the same time.To solve the proposed optimal dispatch model efficiently,the constraints of the problem are reformulated and resolved using the Karush-Kuhn-Tucker(KKT)optimality conditions and linear programming duality theorem.The effectiveness of the strategy is illustrated through a detailed case study.展开更多
Additive manufacturing(AM),also known as three-dimensional printing,is gaining increasing attention from academia and industry due to the unique advantages it has in comparison with traditional subtractive manufacturi...Additive manufacturing(AM),also known as three-dimensional printing,is gaining increasing attention from academia and industry due to the unique advantages it has in comparison with traditional subtractive manufacturing.However,AM processing parameters are difficult to tune,since they can exert a huge impact on the printed microstructure and on the performance of the subsequent products.It is a difficult task to build a process-structure-property-performance(PSPP)relationship for AM using traditional numerical and analytical models.Today,the machine learning(ML)method has been demonstrated to be a valid way to perform complex pattern recognition and regression analysis without an explicit need to construct and solve the underlying physical models.Among ML algorithms,the neural network(NN)is the most widely used model due to the large dataset that is currently available,strong computational power,and sophisticated algorithm architecture.This paper overviews the progress of applying the NN algorithm to several aspects of the AM whole chain,including model design,in situ monitoring,and quality evaluation.Current challenges in applying NNs to AM and potential solutions for these problems are then outlined.Finally,future trends are proposed in order to provide an overall discussion of this interdisciplinary area.展开更多
Solid polymer electrolytes (SPEs) are urgently required for achieving practical all-solid-state lithium metal batteries (ASSLMBs) but remain plagued by low ionic conductivity.Herein,we propose a strategy of salt polar...Solid polymer electrolytes (SPEs) are urgently required for achieving practical all-solid-state lithium metal batteries (ASSLMBs) but remain plagued by low ionic conductivity.Herein,we propose a strategy of salt polarization to fabricate a highly ion-conductive SPE by employing a high-dielectric polymer that can interact strongly with lithium salts.Such a polymer with large dipole moments can guide lithium cations (Li^(+)) to be arranged along the chain,forming a continuous pathway for Li^(+) hopping within the SPE.The as-fabricated SPE,poly(vinylidene difluoride)(PVDF)-LiN(SO_(2)F)_(2)(LiFSI),has an extraordinarily high dielectric constant (up to 10^(8)) and ultrahigh ionic conductivity (0.77×10^(-3)S cm^(-1)).Based on the PVDF–LiFSI SPE,the assembled Li metal symmetrical cell shows excellent Li plating/stripping reversibility at 0.1 m A cm^(-2),0.1 m Ah cm^(-2)over 1500 h^(-1) the ASS LiFePO_(4) batteries deliver long-term cycling stability at 1 C over 350 cycles (2.74 mg cm^(-2)) and an ultralong cycling lifespan of over 2600 h(100 cycles) with high loading (11.5 mg cm^(-2)) at 28°C.First-principles calculations further reveal the ion-dipole interactions-controlled conduction of Li^(+) in PVDF–LiFSI SPE along the PVDF chain.This work highlights the critical role of dielectric permittivity in SPE,and provides a promising path towards high-energy,long-cycling lifespan ASSLMBs.展开更多
文摘The prevalence of nasopharyngeal carcinoma(NPC) is higher in southern China, Hong Kong, and Taiwan than in other areas in the world. Radiotherapy is an important part of treatment for NPC patients, especially those with stage Ⅲ/Ⅳ disease. Subdural empyema is a rare but life-threatening complication in postradiotherapy NPC patients which should be paid more attention. Here, we present the case of a 64-year-old female postradiotherapy NPC patient with subdural empyema complicated with intracranial hemorrhage. She was treated by burr-hole surgery but unfortunately died because of recurrent intracranial hemorrhage. The mechanisms potentially underlying the formation of subdural empyema in postradiotherapy NPC patients and the surgical strategies that can be used in these patients are discussed in this report.
文摘Development of efficient and stable metal catalysts for the selective aqueous phase hydrodeoxygenation(HDO)of biomass-derived oxygenates to value-added biofuels is highly desired.An innovative surface microenvironment modulation strategy was used to construct the nitrogen-doped hollow carbon sphere encapsulated with Pd(Pd@NHCS-X,X:600–800)nanoreactors for catalytic HDO of biomass-derived vanillin in water.The specific surface microenvironments of Pd@NHCS catalysts including the electronic property of active Pd centers and the surface wettability and porous structure of NHCS supports could be well-controlled by the calcination temperature of catalysts.Intrinsic kinetic evaluations demonstrated that the Pd@NHCS-600 catalyst presented a high turnover frequency of 337.77 h^(–1)and a low apparent activation energy of 18.63 kJ/mol.The excellent catalytic HDO performance was attributed to the unique surface microenvironment of Pd@NHCS catalyst based on structure-performance relationship analysis and DFT calculations.It revealed that pyridinic N species dominated the electronic property regulation of Pd sites through electronic metal-support interaction(EMSI)and produced numerous electron-rich active Pd centers,which not only intensified the dissociation and activation of H2 molecules,but also substantially improved the activation capability of vanillin via the enhanced adsorption of–C=O group.The fine hydrophilicity and abundant porous structure promoted the uniform dispersion of catalyst and ensured the effective access of reactants to catalytic active centers in water.Additionally,the Pd@NHCS-600 catalyst exhibited excellent catalytic stability and broad substrate applicability for the selective aqueous phase HDO of various biomass-derived carbonyl compounds.The proposed surface microenvironment modulation strategy will provide a new consideration for the rational design of high-performance nitrogen-doped carbon-supported metal catalysts for catalytic biomass transformation.
基金jointly supported by the National Key R&D Program of China(Grant No.2022YFE0209200)the National Natural Science Foundation of China(Grant Nos.U22A20562,42330607 and 41761144054)the National Large Scientific and Technological Infrastructure“Earth System Science Numerical Simulator Facility”(Earth-Lab)(https://cstr.cn/31134.02.EL)。
文摘Accurate quantification of life-cycle greenhouse gas(GHG)footprints(GHG_(fp))for a crop cultivation system is urgently needed to address the conflict between food security and global warming mitigation.In this study,the hydrobiogeochemical model,CNMM-DNDC,was validated with in situ observations from maize-based cultivation systems at the sites of Yongji(YJ,China),Yanting(YT,China),and Madeya(MA,Kenya),subject to temperate,subtropical,and tropical climates,respectively,and updated to enable life-cycle GHG_(fp)estimation.The model validation provided satisfactory simulations on multiple soil variables,crop growth,and emissions of GHGs and reactive nitrogen gases.The locally conventional management practices resulted in GHG_(fp)values of 0.35(0.09–0.53 at the 95%confidence interval),0.21(0.01–0.73),0.46(0.27–0.60),and 0.54(0.21–0.77)kg CO_(2)e kg~(-1)d.m.(d.m.for dry matter in short)for maize–wheat rotation at YJ and YT,and for maize–maize and maize–Tephrosia rotations at MA,respectively.YT's smallest GHG_(fp)was attributed to its lower off-farm GHG emissions than YJ,though the soil organic carbon(SOC)storage and maize yield were slightly lower than those of YJ.MA's highest SOC loss and low yield in shifting cultivation for maize–Tephrosia rotation contributed to its highest GHG_(fp).Management practices of maize cultivation at these sites could be optimized by combination of synthetic and organic fertilizer(s)while incorporating 50%–100%crop residues.Further evaluation of the updated CNMM-DNDC is needed for different crops at site and regional scales to confirm its worldwide applicability in quantifying GHG_(fp)and optimizing management practices for achieving multiple sustainability goals.
基金Supported by Science and Technology Department of the State Administration of Traditional Chinese Medicine-Zhejiang Provincial Administration of Traditional Chinese Medicine Joint Science and Technology Program,No.GZY-ZJ-KJ-23057Bijie City Science and Technology Program 2023(Second Batch),No.BKH(2023)552024 Guizhou Province Chinese Medicine,Ethnic Medicine Science and Technology Research Special Project,No.QZYY-2024-109.
文摘BACKGROUND In recent years,the number of studies on spondylolisthesis has been increasing,and there are many publications on this disorder.To our knowledge,there is no bibliometric analysis of spondylolisthesis to date.AIM To investigate emerging directions in Spondylolisthesis research and systematically evaluate the academic literature with the highest citation impact within this field.METHODS All data were collected from the Web of Science Core Collection database.Years of publications,countries,journals,institutions and total number of citations were extracted and analyzed by VOSviewer software.In addition,we analyzed the top 100 most-cited articles on spondylolisthesis.RESULTS A total of 1831 articles related to spondylolisthesis were identified.The frequency of publications on spondylolisthesis has increased dramatically over time.Among all countries,United States has contributed the most publications on spondylolisthesis(n=574).The institution with the most articles was the University of California,San Francisco(n=52).Spine topped the list of journals and has published 291 spondylolisthesis-related reports.The hotspot of research changed from posterolateral fusion to interbody fusion.CONCLUSION In recent years,academic investigations on spondylolisthesis have exhibited significant growth.As the inaugural bibliometric evaluation in this domain,our research establishes a methodological framework for synthesizing the historical progression and current advancements of spondylolisthesis studies.
基金supported by the National Natural Science Foundation of China(Grant NO.32360307).
文摘Long-term niche differentiation will lead to the evolution of diverse adaptive strategies for species in diverse environments. The present study selected two Forsythia species, Forsythia mandshurica(Fm)-which naturally occurs in a cold temperate zone and Forsythia suspensa(Fs)-which thrives in a warm temperate zone-to reveal their differential chilling defense mechanisms by integrating morpho-physiological,transcriptomic, and metabolomic data. Transcriptome results show that Fm has evolved in a series of adaptive mechanisms designed to help the plants to cope with chilling stress by enhancing sugar, amino acid, hormone, polyamine, and phenol content to improve cell osmotic potential and to mitigate petal browning. Metabolomic data suggested the increased chilling resistance of Fm relies on in the plant being rich in a-linolenic acid, linoleic acid, as well as two amino acids, Phe and Trp, and has low levels of cinnamic acid and gramine in flowers compared to Fs. A higher abundance of glutathione disulfide and NADPH regulated by glutathione peroxidases and NADPH improved the ability of the cellular antioxidant and reduction-oxidation system stability in Fm;Additionally, the elevated levels of pyruvate, a-ketoglutaric acid, and oxaloacetic acid in Fm contributed to a significantly enhanced ATP production in mitochondria. Through Ka/Ks and gene expression analysis,four transcription factors, EVM0025036(bHLH), EVM0010639 and EVM0007275(AP2), and EVM0025908(bZIP) were identified that may contribute to the high cold tolerance of Fm. These adaptations highlight the intricate interplay between genetic and physiological processes that shape the survival strategies of plants in response to their specific ecological niches.
基金supported by the National Natural Science Fund of China(Nos.52005153,12227801,32300666,12072005,U23A2607)the Tianjin"Project+Team"Key Training Program,China(No.XC202052)+4 种基金the Key Program of Research and Development of Hebei Province,China(Nos.202030507040009,23311812D)the Natural Science Foundation of Hebei Province,China(No.E2023202183)the Project of High-Level Team Construction Introduction of Hebei Province,China(No.244A7620D)the Research Cooperation Project of Universities Stationed in Hebei Province and Shijiazhuang City,China(No.241080114A)Hebei Province Military-Civilian Integration Science and Technology Innovation Project,China(No.SJMYF2022X15)。
文摘Fiber Metal Laminates(FMLs),as high-performance composite materials,demonstrate exceptional potential in a wide range of applications,such as aeronautical and astronautical industries.However,the traditional cured FMLs possess complex interlayer stresses and low forming limits,restricting further promotion and application of FMLs.Low-constraint FMLs exhibit a lower forming resistance and better formability due to no curing during the forming process;however,the formation mechanism and response are not clear.This paper presents the Forming Limit Diagram(FLD)of low-constraint GLARE(glass fiber reinforced aluminum laminates)based on the forming limit test,and compares it with the conventionally cured laminates to evaluate the differences in the forming limit.In addition,combined with the analysis of failure mechanism and micro-deformation mechanism of specimens,the influence of different temperatures(20–80℃)and forming states(width)on the deformation performance of laminates is further explored.The results reveal that the forming limit curve of low-constraint laminates shifts up with the increase of temperature,the forming limit initially increases with the increase of width,then followed by a gradual decrease,and the maximum principal strain of low-constraint laminates is increased by 29% at 80℃ compared to 20℃.The cured laminate has a principal strain range of 0–0.02,while the low-constraint laminates have a principal strain range of 0.03–0.14.Compared with cured laminates,low-constraint laminates possess a higher forming limit due to the improvement in deformable degree between layers by resin flow and fiber slippage,which enhances their formability.This study is expected to serve as a reference for establishing forming limit criteria and optimizing forming schemes for low-constraint laminates.
基金co-supported by the financial support from the Fundamental Research Funds for the Central Universities,China(Nos.YWF-23-L-1012,YWF-22-L-1017)the National Natural Science Foundation of China(No.52005020)。
文摘The performance of welded Ni-based superalloys at high temperatures is essential to be evaluated due to their particular service environment for aero-engines and high-speed aircrafts.The tensile properties and related microstructural evolutions such as the carbide precipitate and grain of a laser-welded Ni-based alloy were experimentally and numerically investigated at different temperatures(20,300,500,800℃).The results show that at room temperature,the strength of the Base Material(BM)was slightly smaller,with a difference of less than 1%,than the Welded Material(WM),which can be attributed to the more uniformly distributed needle-shaped carbide precipitates in the WM than those nonuniformly coarser spherical ones in the BM.While at 300℃ and 500℃,the strength of WM decreased more obviously compared with that of BM due to the more apparent growth of grain:13.52%loss in yield strength in WM alloys as compared with BM alloys at 300℃,and 16.57% at 500℃.At 800℃,the strength of BM and WM both decreased to a similar level due to Dynamic Recrystallization(DRX).However,a much higher elongation was observed for the BM than WM(less than 50%of BM),which can be attributed to the enhanced dislocation accumulation capability of the large spherical carbides along grain boundaries on the fracture surface in BM.Furthermore,a unified model considering the welding effects on both microstructures(dislocation,carbides,and grain)and mechanical properties evolutions at different temperatures was developed and validated.Based on this model,the key temperature ranges(20–600℃)where apparent weakening of strength and uniform plasticity occurs for welded structures were identified,providing a direct guidance for potential structure and process design.
基金supported by the Natural Science Foundation of Fujian Province(No.2022J01755)。
文摘Objective:This study aimed to develop and validate a predictive model for postoperative complications in gastrointestinal cancer patients using a large multicenter database,based on machine learning algorithms.Methods:We analyzed the clinicopathological data of 3,926 gastrointestinal cancer patients from the Prevalence of Abdominal Complications After GastroEnterological surgery(PACAGE)database,covering 20 medical centers from December 2018 to December 2020.The predictive performance was evaluated using receiver operating characteristic(ROC)curves and Brier Score.Results:The patients were divided into gastric(2,271 cases)and colorectal cancer(1,655 cases)groups and further divided into training and external validation sets.The overall postoperative complication rates for gastric and colorectal cancer groups were 18.1%and 14.8%,respectively.The most common complication was the intraabdominal infection in both gastric and colorectal cancer groups.In the training set,the Random Forest(RF)model predicted the highest mean area under the curve(AUC)values for overall complications and different types of complications,in both the gastric cancer group and the colorectal cancer group,with similar results obtained in the external validation set.ROC curve analysis showed good predictive performance of the RF model for overall and infectious complications.An application-based clinical tool was developed for easy application in clinical practice.Conclusions:This model demonstrated good predictive performance for overall and infectious complications based on the multi-center database,supporting clinical decision-making and personalized treatment strategies.
基金the National Natural Science Foundation of China under grant No.12372173the Natural Science Foundation of Shanghai under grant No.23ZR1468600.
文摘Silicon,a leading candidate for electrode material for lithium-ion batteries,has garnered significant attention.During the initial lithiation process,the alloying reaction between silicon and lithium transforms the pristine silicon microstructure from crystalline to amorphous,resulting in plastic deformation of the amorphous phase.This study proposes the free volume theory to develop a fully coupled Cahn-Hilliard phase-field model that integrates viscoplastic deformation,free volume evolution,and diffusion.This model investigates the chemophysical phenomenon of self-limiting behavior occurring during the initial lithiation of silicon anodes.Unlike most existing models,the proposed model considers free volume-dependent diffusion using a physically-based approach.The model’s temporal variation in the lithiated phase thickness aligns well with experimental results,confirming the model’s accuracy.Stress field calculations reveal the coexistence of compressive and tensile stresses within the lithiated phase,which may not cause the limiting effect under the frame of the stress-induced diffusion.Analyses indicate that high effective stress increases free volume,enhancing lithium diffusion and augmenting the diffusion coefficient.Reducing the diffusion coefficient in the lithiated phase due to free volume evolution is the primary cause of self-limiting lithiation.
基金supported by the National Natural Science Foundation of China(32172117,32101834)the Shandong Province Agricultural Major Technology Collaborative Promotion Plan Project(SDNYXTTG-2023-33)+1 种基金Postdoctoral Science Foundation of China(2022M711968)the Natural Science Foundation of Shandong Province(ZR2020QC106).
文摘Population size plays a crucial role in determining wheat yields.Altered carbohydrate accumulation resulting from increased competition between populations and individuals leads to poor-quality stems.The sowing date can mitigate competition in densely planted populations.However,the underlying mechanism by which it confers resistance to wheat lodging remains elusive.In this study,Zimai 28(lodging-sensitive variety) and Shannong 28(lodging-resistant variety) were used with three sowing treatments on October 22(S1),October 28(S2),and November 3(S3).The sowing rate was adjusted to ensure adequate population size and consistency in the overwintering populations across sowing dates(300 plant m^(-2)for S1,375 plant m^(-2)for S2,and 525 plant m^(-2)for S3),The lodging resistance in winter wheat was increased by delayed sowing and increased sowing rate,which led to a reduction in tiller numbers and fostered primary stem development.A reduction in the overwinter cumulative temperature from 500 to 450℃,coupled with an elevation in sowing rates from 300 to 375 plant m^(-2)(transition from S1 to S2),corresponded with a notable increase in structural carbohydrates(lignin,cellulose,hemicellulose,and pectin) by 175.07 mg g^(-1).Additionally,there was a moderate increase in non-structural carbohydrates,including soluble sugars and starch,by 15.54 mg g^(-1).Delayed sowing and increased sowing rate elevated the precursor contents of lignin synthesis.Enhanced metabolic activity of related pathways ultimately increased dimer/trimer content.In summary,this study highlights the pivotal role of lignin metabolites and cross-linked structures in determining the stem stiffness breaking strength.
基金financially supported by the National Natural Science Foundation of China(Nos.22205196 and U1904215)the Natural Science Foundation of Jiangsu Province(No.BK20210790)the start-up fundings from Yangzhou University
文摘Electrochemically induced surface reconstruction offers a novel approach for in situ modulation of the surface structure of nanomaterials.However,comprehensive studies on the surface reconstruction behavior of nanomaterials under diverse electrochemical operations remain limited.Here,exemplified by three electrochemical operations,including cyclic voltammetry(CV),squarewave potential(SWP)and chronoamperometry(CA),we reveal the structural evolution behavior and the corresponding electrocatalytic activity of bimetallic telluride hollow nanorods(Ir_(1-x)Ru_(x)0Te_(2)HNRs).It was found that the surface Te atoms in Ir_(1-x)Ru_(x)0Te_(2)HNRs undergo preferential leaching during the CV and SWP processes,ultimately leading to the formation of a metal alloy shell.In contrast,during the CA process,the surface reconstruction induced by Te leaching was suppressed by the adsorption of anions on the electrode surface.Electrocatalytic tests show that the CV activated Ir_(0.75)Ru_(0.25)Te_(2)HNRs exhibit excellent activity for the hydrogen oxidation reaction in 0.1 M KOH,with a mass activity of 686 Ag^(-1)at an overpotential of50 mV,which is 2.9 times higher than that of commercialPt/C catalyst.Density functional theory(DFT)computation reveals that the incorporation of Ru optimizes the hydroxyl binding energy of IrRu alloy,thus resulting in the reduced reaction energy barrier of hydrogen oxidation reaction.This work provides a new insight into the design of efficient catalysts through electrochemical surface engineering.
基金supported by the National Natural Science Foundation of China(Grant no.52463025,and 52062035)the Major Discipline Academic and Technical Leaders Training Program of Jiangxi Province(Grant no.20213BCJ22056)+2 种基金the Key R&D Program of Jiangxi Province(Grant no.20223BBE51028)the Jiangxi Province Key Laboratory of Lithium-ion Battery Materials and Application(2024SSY05202)the Jiangxi Province Graduate Innovation Special Fund Project(YC2023-B004)。
文摘Oxygen release from Ni-rich cathode is one of the major structural degradations resulting in rapid performance fading in lithium-ion batteries(LIBs).The energy gap between the transition metals(TM)-d band and the O-p band serves as an effective evaluation metric in characterizing the potential for oxygen release.Given that the primary oxidation factors of NCM811 materials vary at different states of charge(SOC),this study employs high-throughput density functional theory(DFT)calculations combined with machine learning(ML)to systematically investigate the regulation mechanism of heteroatoms on the energy gap between the TM-d band(TM=Ni,Co)and O-p band at various SOC levels.Highthroughput DFT calculations were used to study doping thermodynamic stability and complete the database.The results indicate that dopant atoms remain at their original sites even at 50%SOC.Correlation analysis reveals that at 0 SOC,the dopant reduces Ni-O bonding interactions by forming its own bonds with oxygen,thereby preventing lattice oxygen escape and weakening the oxygen binding of the system during Ni redox.At 50%SOC,the dopant and Co atoms synergistically strengthen their bonding interactions with oxygen,thereby maintaining structural stability and inhibiting lattice oxygen escape.Based on R^(2)and root-mean-square error(RMSE),the gradient boosting regression(GBR)algorithm is identified as optimal for predicting the energy gaps between the Ni-d band and O-p band,as well as between the Co-d band and O-p band.Feature importance analysis demonstrates that the magnetic moment(Dma)of the doped atom significantly contributes to the prediction of ΔNi-O and ΔCo-O.In this study,the energy gap regulation mechanisms of Ni-d/O-p and Co-d/O-p are systematically investigated using non-empirical first principle calculations combined with data-driven machine learning,aiming to provide insights into the electrochemical stability of NCM811 and related materials.
基金Supported by Xi’an Science and Technology Plan,No.23YXYJ0172.
文摘BACKGROUND The hepatic venous pressure gradient serves as a crucial parameter for assessing portal hypertension and predicting clinical decompensation in individuals with cirrhosis.However,owing to its invasive nature,there has been growing interest in identifying noninvasive alternatives.Transient elastography offers a promising approach for measuring liver stiffness and spleen stiffness,which can help estimate the likelihood of decompensation in patients with chronic liver disease.AIM To investigate the predictive ability of the liver stiffness measurement(LSM)and spleen stiffness measurement(SSM)in conjunction with other noninvasive indicators for clinical decompensation in patients suffering from compensatory cirrhosis and portal hypertension.METHODS This study was a retrospective analysis of the clinical data of 200 patients who were diagnosed with viral cirrhosis and who received computed tomography,transient elastography,ultrasound,and endoscopic examinations at The Second Affiliated Hospital of Xi’an Jiaotong University between March 2020 and November 2022.Patient classification was performed in accordance with the Baveno VI consensus.The area under the curve was used to evaluate and compare the predictive accuracy across different patient groups.The diagnostic effectiveness of several models,including the liver stiffness-spleen diameter-platelet ratio,variceal risk index,aspartate aminotransferase-alanine aminotransferase ratio,Baveno Ⅵ criteria,and newly developed models,was assessed.Additionally,decision curve analysis was carried out across a range of threshold probabilities to evaluate the clinical utility of these predictive factors.RESULTS Univariate and multivariate analyses demonstrated that SSM,LSM,and the spleen length diameter(SLD)were linked to clinical decompensation in individuals with viral cirrhosis.On the basis of these findings,a predictive model was developed via logistic regression:Ln[P/(1-P)]=-4.969-0.279×SSM+0.348×LSM+0.272×SLD.The model exhibited strong performance,with an area under the curve of 0.944.At a cutoff value of 0.56,the sensitivity,specificity,positive predictive value,and negative predictive value for predicting clinical decompensation were 85.29%,88.89%,87.89%,and 86.47%,respectively.The newly developed model demonstrated enhanced accuracy in forecasting clinical decompensation among patients suffering from viral cirrhosis when compared to four previously established models.CONCLUSION Noninvasive models utilizing SSM,LSM,and SLD are effective in predicting clinical decompensation among patients with viral cirrhosis,thereby reducing the need for unnecessary hepatic venous pressure gradient testing.
基金financially supported by the National Key Research and Development Program(No.2023YFB3712403)the National Natural Science Foundation of China(Nos.52201112,52071066,U22A20106,and U22A20173).
文摘Recycling-oriented alloy design is a crucial part of material sustainability,as it reduces the need for raw material extraction and minimises environmental impact.This requires that scraps be reused or repurposed effectively,even when the scraps are co-mingled and have higher costs for further sorting and separation.In this work,we explore an alloy design concept by creating a compositionally flexible domain that can recycle multiple alloy grades and yet maintain relatively consistent properties across chemical variations.This is demonstrated through the Fe-Cr-Ni-Mn system to identify compositionally flexible austenitic stainless steels(CF-ASS)and accommodate the recycling of mixed austenitic stainless steel scraps.Alloys within the nominal composition spaces exhibit relatively consistent mechanical properties and corrosion resistance despite significant variations in different alloy compositions.We illustrate how we can utilise the compositionally flexible austenitic stainless steels to recycle mixed 200 and 300-series stainless steel and ferronickel scraps,demonstrating its practical viability.While this demonstration focuses on the stainless steel system,the underlying principles can be extended to other systems related to mixed scrap recycling.
基金supported by the National Key R&D Program of China (No. 2022YFE0204100)the National Natural Science Foundation of China (12205067 and 12375199)the Fundamental Research Funds for the Central Universities (Grant No. HIT.OCEF. 2022036)。
文摘This paper establishes an amplitude modulation heating model, simulating the far-field radiation of ELF/VLF signals generated by modulation heating, as well as the specific location and longitudinal extent of the radiation source. We consider various modulation waveforms and find that square-wave modulation has the highest excitation efficiency for ELF/VLF signals, and that square-wave modulation with a smaller duty cycle(<50%) exhibits higher excitation efficiency for ELF/VLF signals, while the sin^(2)t waveform modulation yields the lowest proportion of harmonic energy in the generated signals. The amplitude of the second harmonic generated by the sin^(2)t waveform is less than one-tenth that of the fundamental frequency, and the energy of higher-frequency harmonics can be negligibly small compared with those of the fundamental wave. It is a challenging task to achieve a balance between enhancing the excitation efficiency of ELF/VLF signals and also suppressing harmonics generated by the modulated heating process. This is because the harmonics are correspondingly enhanced as the excitation efficiency of the signals is increased. However, we find that under conditions of varying effective radiant power and modulation frequency, as long as the modulation waveform is unchanged, the energy ratio between the fundamental frequency signal generated by modulated heating and each harmonic is relatively fixed, with changes only in signal intensity and the location of the radiation source zone. This implies that one can first select modulation waveforms that make the signal less prone to distortion, then increase the effective radiated power to enhance the signal strength, without concern for harmonic interference of the fundamental signal.
文摘AIM: To retrospectively analyze the computed tomography (CT) and magnetic resonance imaging (MRI) appearances of primary clear cell carcinoma of the liver (PCCCL) and compare the imaging appearances of PCCCL and common type hepatocellular carcinoma (CHCC) to determine whether any differences exist between the two groups. METHODS: Twenty cases with pathologically proven PCCCL and 127 cases with CHCC in the Second Affiliated Hospital of Sun Yat-sen University were included in this study. CT or MRI images from these patients were retrospectively analyzed. The following imaging findings were reviewed: the presence of liver cirrhosis, tumor size, the enhancement pattern on dynamic contrast scanning, the presence of pseudo capsules, tumor rupture, portal vein thrombosis and lymph node metastasis. RESULTS: Both PCCCL and CHCC were prone to occur in patients with liver cirrhosis, the association rate of liver cirrhosis was 80.0% and 78.7%, respectively (P > 0.05). The mean sizes of PCCCL and CHCC tumors were (7.28 ± 4.25) cm and (6.96 ± 3.98) cm, respectively. Small HCCs were found in 25.0% (5/20) of PCCCL and 19.7% (25/127) of CHCC cases. No significant differences in mean size and ratio of small HCCs were found between the two groups (P = 0.658 and 0.803, respectively). Compared with CHCC patients, PCCCL patients were more prone to form pseudo capsules (49.6% vs 75.0%, P = 0.034). Tumor rupture, typical HCC enhancement patterns and portal vein tumor thrombosis were detected in 15.0% (3/20), 72.2% (13/18) and 20.0% (4/20) of patients with PCCCL and 3.1% (4/127), 83.6% (97/116) and 17.3% (22/127) of patients with CHCC, respectively. There were no significant differences between the two groups (all P > 0.05). No patients with PCCCL and 2.4% (3/127) of patients with CHCC showed signs of lymph node metastasis (P > 0.05). CONCLUSION: The imaging characteristics of PCCCL are similar to those of CHCC and could be useful for differentiating these from other liver tumors (such as hemangioma and hepatic metastases). PCCCLs are more prone than CHCCs to form pseudo capsules.
基金supported by the Natural Science Foundation of Guangdong Province(No.2015A030313089)the Medical Science and Technology Research Foundation of Guangdong Province(No.B2014160)the Major Program of Collaborative Innovation of Guangzhou(No.201508030042)
文摘Background: Gastroenteropancreatic neuroendocrine neoplasms(GEP-NENs) are a heterogeneous group of rare tumors. Many issues in terms of epidemiologic features, pathogenesis, and treatment of GEP-NENs are still under discussion. Our study aimed to analyze the clinicopathologic characteristics and prognosis of Chinese patients with GEP-NENs.Methods: Complete clinicopathologic data and survival information of 1183 patients with GEP-NENs treated between 2005 and 2015 were collected from five medical centers in Guangdong Province, China. Patient survival was estimated using the Kaplan–Meier method and analyzed using the log-rank test; prognostic factors were analyzed using the Cox proportional hazards model.Results: The most common tumor location was the rectum(37.4%), followed by the pancreas(28.1%), stomach(20.7%), small intestine(7.2%), appendix(3.4%), and colon(3.3%). After initial definitive diagnosis, 1016(85.9%) patients underwent surgery. The 1-, 3-, and 5-year overall survival(OS) rates for the entire cohort were 87.9%, 78.5%, and 72.8%, respectively. The 3-year OS rates of patients with G1, G2, and G3 tumors were 93.1%, 82.7%, and 43.1%, respectively(P < 0.001). The 3-year OS rates of patients with stage I, II, III, and IV tumors were 96.0%, 87.3%, 64.0%, and 46.8%, respectively(P < 0.001). Patients with distant metastasis who underwent palliative surgery had a longer survival than those who did not(P = 0.003). Similar survival benefits of palliative surgery were observed in patients with neuroendocrine tumor(P y, M category, and sur= 0.031) or neuroendocrine carcinoma(P gery were found to be independent prog= 0.046). In multivariate analysis, age, grade, N categornostic factors.Conclusions: Patients with GEP-NENs who are women, younger than 50 years old, have smaller tumor size, have lower tumor grade, have lower T/N/M category, and who undergo surgery can have potentially longer survival time. Our data showed that surgery can improve the prognosis of GEP-NEN patients with distant metastasis. However, randomized controlled trials need to be conducted to establish the optimal criteria for selecting patients to undergo surgery.
基金supported by the Science and Technology Project of Sichuan Electric Power Company“Power Supply Guarantee Strategy for Urban Distribution Networks Considering Coordination with Virtual Power Plant during Extreme Weather Event”(No.521920230003).
文摘Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the coordination with virtual power plants(VPPs).The proposed strategy improves systemflexibility and responsiveness by optimizing the power adjustment of flexible resources.In the proposed strategy,theGaussian Process Regression(GPR)is firstly employed to determine the adjustable range of aggregated power within the VPP,facilitating an assessment of its potential contribution to power supply support.Then,an optimal dispatch model based on a leader-follower game is developed to maximize the benefits of the VPP and flexible resources while guaranteeing the power balance at the same time.To solve the proposed optimal dispatch model efficiently,the constraints of the problem are reformulated and resolved using the Karush-Kuhn-Tucker(KKT)optimality conditions and linear programming duality theorem.The effectiveness of the strategy is illustrated through a detailed case study.
文摘Additive manufacturing(AM),also known as three-dimensional printing,is gaining increasing attention from academia and industry due to the unique advantages it has in comparison with traditional subtractive manufacturing.However,AM processing parameters are difficult to tune,since they can exert a huge impact on the printed microstructure and on the performance of the subsequent products.It is a difficult task to build a process-structure-property-performance(PSPP)relationship for AM using traditional numerical and analytical models.Today,the machine learning(ML)method has been demonstrated to be a valid way to perform complex pattern recognition and regression analysis without an explicit need to construct and solve the underlying physical models.Among ML algorithms,the neural network(NN)is the most widely used model due to the large dataset that is currently available,strong computational power,and sophisticated algorithm architecture.This paper overviews the progress of applying the NN algorithm to several aspects of the AM whole chain,including model design,in situ monitoring,and quality evaluation.Current challenges in applying NNs to AM and potential solutions for these problems are then outlined.Finally,future trends are proposed in order to provide an overall discussion of this interdisciplinary area.
基金supported by the National Natural Science Foundation of China (No. 51877132)the Program of Shanghai Academic Research Leader (No. 21XD1401600)the Beijing Natural Science Foundation (No. 2214061)。
文摘Solid polymer electrolytes (SPEs) are urgently required for achieving practical all-solid-state lithium metal batteries (ASSLMBs) but remain plagued by low ionic conductivity.Herein,we propose a strategy of salt polarization to fabricate a highly ion-conductive SPE by employing a high-dielectric polymer that can interact strongly with lithium salts.Such a polymer with large dipole moments can guide lithium cations (Li^(+)) to be arranged along the chain,forming a continuous pathway for Li^(+) hopping within the SPE.The as-fabricated SPE,poly(vinylidene difluoride)(PVDF)-LiN(SO_(2)F)_(2)(LiFSI),has an extraordinarily high dielectric constant (up to 10^(8)) and ultrahigh ionic conductivity (0.77×10^(-3)S cm^(-1)).Based on the PVDF–LiFSI SPE,the assembled Li metal symmetrical cell shows excellent Li plating/stripping reversibility at 0.1 m A cm^(-2),0.1 m Ah cm^(-2)over 1500 h^(-1) the ASS LiFePO_(4) batteries deliver long-term cycling stability at 1 C over 350 cycles (2.74 mg cm^(-2)) and an ultralong cycling lifespan of over 2600 h(100 cycles) with high loading (11.5 mg cm^(-2)) at 28°C.First-principles calculations further reveal the ion-dipole interactions-controlled conduction of Li^(+) in PVDF–LiFSI SPE along the PVDF chain.This work highlights the critical role of dielectric permittivity in SPE,and provides a promising path towards high-energy,long-cycling lifespan ASSLMBs.
